id stringlengths 9 14 | submitter stringlengths 1 56 ⌀ | authors stringlengths 5 7.68k | title stringlengths 3 299 | comments stringlengths 1 1.15k ⌀ | journal-ref stringlengths 9 298 ⌀ | doi stringlengths 12 97 ⌀ | report-no stringlengths 3 341 ⌀ | categories stringclasses 869 values | license stringclasses 9 values | orig_abstract stringlengths 16 2.44k | versions listlengths 1 39 | update_date stringlengths 10 10 | authors_parsed listlengths 1 565 | abstract stringlengths 13 2.44k |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
hep-ph/0612158 | Walter Winter | Raj Gandhi, Walter Winter | Physics with a very long neutrino factory baseline | 27 pages, 11 figures. Minor changes, references added; version to
appear in Phys. Rev. D | Phys.Rev.D75:053002,2007 | 10.1103/PhysRevD.75.053002 | null | hep-ph hep-ex | null | We discuss the neutrino oscillation physics of a very long neutrino factory
baseline over a broad range of lengths (between 6000 km and 9000 km), centered
on the ``magic baseline'' ($\sim$ 7500 km) where correlations with the leptonic
CP phase are suppressed by matter effects. Since the magic baseline depends
only on the density, we study the impact of matter density profile effects and
density uncertainties over this range, and the impact of detector locations off
the optimal baseline. We find that the optimal constant density describing the
physics over this entire baseline range is about 5% higher than the average
matter density. This implies that the magic baseline is significantly shorter
than previously inferred. However, while a single detector optimization
requires fine-tuning of the (very long) baseline length, its combination with a
near detector at a shorter baseline is much less sensitive to the far detector
location and to uncertainties in the matter density. In addition, we point out
different applications of this baseline which go beyond its excellent
correlation and degeneracy resolution potential. We demonstrate that such a
long baseline assists in the improvement of the $\theta_{13}$ precision and in
the resolution of the octant degeneracy. Moreover, we show that the neutrino
data from such a baseline could be used to extract the matter density along the
profile up to 0.24% at $1 \sigma$ for large $\sin^2 2 \theta_{13}$, providing a
useful discriminator between different geophysical models.
| [
{
"created": "Wed, 13 Dec 2006 12:52:26 GMT",
"version": "v1"
},
{
"created": "Fri, 23 Feb 2007 10:48:07 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Gandhi",
"Raj",
""
],
[
"Winter",
"Walter",
""
]
] | We discuss the neutrino oscillation physics of a very long neutrino factory baseline over a broad range of lengths (between 6000 km and 9000 km), centered on the ``magic baseline'' ($\sim$ 7500 km) where correlations with the leptonic CP phase are suppressed by matter effects. Since the magic baseline depends only on the density, we study the impact of matter density profile effects and density uncertainties over this range, and the impact of detector locations off the optimal baseline. We find that the optimal constant density describing the physics over this entire baseline range is about 5% higher than the average matter density. This implies that the magic baseline is significantly shorter than previously inferred. However, while a single detector optimization requires fine-tuning of the (very long) baseline length, its combination with a near detector at a shorter baseline is much less sensitive to the far detector location and to uncertainties in the matter density. In addition, we point out different applications of this baseline which go beyond its excellent correlation and degeneracy resolution potential. We demonstrate that such a long baseline assists in the improvement of the $\theta_{13}$ precision and in the resolution of the octant degeneracy. Moreover, we show that the neutrino data from such a baseline could be used to extract the matter density along the profile up to 0.24% at $1 \sigma$ for large $\sin^2 2 \theta_{13}$, providing a useful discriminator between different geophysical models. |
2204.04374 | Ye-Ling Zhou | Yongcheng Wu, Ke-Pan Xie and Ye-Ling Zhou | Collapsing domain walls beyond $Z_2$ | 9 pages, 4 figures, refs and comments added, accepted for publication
in PRD | null | 10.1103/PhysRevD.105.095013 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Discrete symmetries are widely imposed in particle theories. It is well-known
that the spontaneous breaking of discrete symmetries leads to domain walls.
Current studies of domain walls have focused on those from the spontaneous
breaking of a $Z_2$ symmetry. Larger discrete symmetries have multiple
degenerate vacua, leading to the domain walls in principle different from the
simplest $Z_2$ domain wall. We take domain walls from $Z_N$ symmetry breaking
as an illustrative study, and study in detail the $Z_3$ case, in which
semi-analytical results for the tension and thickness of domain walls are
derived. Explicit symmetry breaking terms lead to the dynamics of domain walls
collapsing more complicated than the $Z_2$ case. Gravitational wave signals
deviate from those from $Z_2$ domain walls.
| [
{
"created": "Sat, 9 Apr 2022 03:10:36 GMT",
"version": "v1"
},
{
"created": "Fri, 29 Apr 2022 00:38:41 GMT",
"version": "v2"
}
] | 2022-05-25 | [
[
"Wu",
"Yongcheng",
""
],
[
"Xie",
"Ke-Pan",
""
],
[
"Zhou",
"Ye-Ling",
""
]
] | Discrete symmetries are widely imposed in particle theories. It is well-known that the spontaneous breaking of discrete symmetries leads to domain walls. Current studies of domain walls have focused on those from the spontaneous breaking of a $Z_2$ symmetry. Larger discrete symmetries have multiple degenerate vacua, leading to the domain walls in principle different from the simplest $Z_2$ domain wall. We take domain walls from $Z_N$ symmetry breaking as an illustrative study, and study in detail the $Z_3$ case, in which semi-analytical results for the tension and thickness of domain walls are derived. Explicit symmetry breaking terms lead to the dynamics of domain walls collapsing more complicated than the $Z_2$ case. Gravitational wave signals deviate from those from $Z_2$ domain walls. |
hep-ph/0407090 | Balaji Katlai K. R. S. | K.R.S. Balaji, Robert H. Brandenberger | Single Field Baryogenesis | 4 pages, LaTex | Phys.Rev.Lett. 94 (2005) 031301 | 10.1103/PhysRevLett.94.031301 | BROWN-HET-14-04, MCGILL-16-04 | hep-ph astro-ph gr-qc hep-th | null | We propose a new variant of the Affleck-Dine baryogenesis mechanism in which
a rolling scalar field couples directly to left- and right-handed neutrinos,
generating a Dirac mass term through neutrino Yukawa interactions. In this
setup, there are no explicitly CP violating couplings in the Lagrangian. The
rolling scalar field is also taken to be uncharged under the $B - L$ quantum
numbers. During the phase of rolling, scalar field decays generate a
non-vanishing number density of left-handed neutrinos, which then induce a net
baryon number density via electroweak sphaleron transitions.
| [
{
"created": "Wed, 7 Jul 2004 16:04:39 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Balaji",
"K. R. S.",
""
],
[
"Brandenberger",
"Robert H.",
""
]
] | We propose a new variant of the Affleck-Dine baryogenesis mechanism in which a rolling scalar field couples directly to left- and right-handed neutrinos, generating a Dirac mass term through neutrino Yukawa interactions. In this setup, there are no explicitly CP violating couplings in the Lagrangian. The rolling scalar field is also taken to be uncharged under the $B - L$ quantum numbers. During the phase of rolling, scalar field decays generate a non-vanishing number density of left-handed neutrinos, which then induce a net baryon number density via electroweak sphaleron transitions. |
0807.2024 | Zhenjun Xiao | Zhi-Qing Zhang, Zhen-Jun Xiao | $B \to \rho(\omega, \phi) \etap $ Decays and NLO contributions in the
pQCD Approach | 27 pages, 8 ps/eps figures, typo in references removed | null | null | NJNU-TH-08-12 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | By employing the perturbative QCD (pQCD) factorization approach, we
calculated some important next-to-leading-order(NLO) contributions to the
two-body charmless hadronic decays $B^+ \to \rho^+ \eta^{(\prime)}$ and $B^0
\to \rho^0(\omega, \phi) \eta^{(\prime)}$, induced by the vertex QCD
corrections, the quark-loops as well as the chromo-magnetic penguins. From the
numerical results and phenomenological analysis we find that (a) for $B^\pm \to
\rho^\pm \etap$ decays, the partial NLO contributions to branching ratios are
small in magnitude; (b) for $B^0 \to \rho^0(\omega,\phi) \etap$ decays, the NLO
contributions can provide significant enhancements to the leading order
predictions of their branching ratios; and (c) the pQCD predictions for the
CP-violating asymmetries $\acp^{dir}(B^\pm \to \rho^\pm \etap)$ are consistent
with the data, while the predicted $\acp(B^0 \to \rho^0(\omega)\etap)$ are
generally large in magnitude and could be tested by the forthcoming LHCb
experiments.
| [
{
"created": "Sun, 13 Jul 2008 14:32:52 GMT",
"version": "v1"
},
{
"created": "Thu, 17 Jul 2008 23:36:03 GMT",
"version": "v2"
}
] | 2008-07-18 | [
[
"Zhang",
"Zhi-Qing",
""
],
[
"Xiao",
"Zhen-Jun",
""
]
] | By employing the perturbative QCD (pQCD) factorization approach, we calculated some important next-to-leading-order(NLO) contributions to the two-body charmless hadronic decays $B^+ \to \rho^+ \eta^{(\prime)}$ and $B^0 \to \rho^0(\omega, \phi) \eta^{(\prime)}$, induced by the vertex QCD corrections, the quark-loops as well as the chromo-magnetic penguins. From the numerical results and phenomenological analysis we find that (a) for $B^\pm \to \rho^\pm \etap$ decays, the partial NLO contributions to branching ratios are small in magnitude; (b) for $B^0 \to \rho^0(\omega,\phi) \etap$ decays, the NLO contributions can provide significant enhancements to the leading order predictions of their branching ratios; and (c) the pQCD predictions for the CP-violating asymmetries $\acp^{dir}(B^\pm \to \rho^\pm \etap)$ are consistent with the data, while the predicted $\acp(B^0 \to \rho^0(\omega)\etap)$ are generally large in magnitude and could be tested by the forthcoming LHCb experiments. |
2109.11379 | Ye-Ling Zhou | Georgianna Charalampous, Stephen F. King, George K. Leontaris, Ye-Ling
Zhou | Flipped SU(5) with modular $A_4$ symmetry | 27 pages, 1 figure, comments added, published in PRD | Phys.Rev.D 104 (2021) 115015 | 10.1103/PhysRevD.104.115015 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study Flipped $SU(5)\times U(1)$ Grand Unified Theories (GUTs) with
$\Gamma_3\simeq A_4$ modular symmetry. We propose two models with different
modular weights assignments, where the fermion mass hierarchy can arise from
weighton fields. In order to relax the constraint on the Dirac neutrino Yukawa
matrix we appeal to mechanisms which allow incomplete GUT representations,
allowing a good fit to quark and charged lepton masses and quark mixing for a
single modulus field $\tau$, with the neutrino masses and lepton mixing well
determined by the type I seesaw mechanism, at the expense of some tuning. We
also discuss the double seesaw possibility allowed by the extra singlets
generically predicted in such string inspired theories.
| [
{
"created": "Thu, 23 Sep 2021 13:50:08 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Dec 2021 06:23:40 GMT",
"version": "v2"
}
] | 2021-12-22 | [
[
"Charalampous",
"Georgianna",
""
],
[
"King",
"Stephen F.",
""
],
[
"Leontaris",
"George K.",
""
],
[
"Zhou",
"Ye-Ling",
""
]
] | We study Flipped $SU(5)\times U(1)$ Grand Unified Theories (GUTs) with $\Gamma_3\simeq A_4$ modular symmetry. We propose two models with different modular weights assignments, where the fermion mass hierarchy can arise from weighton fields. In order to relax the constraint on the Dirac neutrino Yukawa matrix we appeal to mechanisms which allow incomplete GUT representations, allowing a good fit to quark and charged lepton masses and quark mixing for a single modulus field $\tau$, with the neutrino masses and lepton mixing well determined by the type I seesaw mechanism, at the expense of some tuning. We also discuss the double seesaw possibility allowed by the extra singlets generically predicted in such string inspired theories. |
hep-ph/9905550 | Andre Hoang | A. H. Hoang (CERN) | 1S and MSbar Bottom Quark Masses from Upsilon Sum Rules | 20 pages, latex; numbers in Tabs. 2,3,4 corrected, a reference and a
comment on the fitting procedure added, typos in Eqs. 2 and 23 eliminated | Phys.Rev.D61:034005,2000 | 10.1103/PhysRevD.61.034005 | CERN/TH 99-152 | hep-ph | null | The bottom quark 1S mass, $M_b^{1S}$, is determined using sum rules which
relate the masses and the electronic decay widths of the $\Upsilon$ mesons to
moments of the vacuum polarization function. The 1S mass is defined as half the
perturbative mass of a fictitious ${}^3S_1$ bottom-antibottom quark bound
state, and is free of the ambiguity of order $\Lambda_{QCD}$ which plagues the
pole mass definition. Compared to an earlier analysis by the same author, which
had been carried out in the pole mass scheme, the 1S mass scheme leads to a
much better behaved perturbative series of the moments, smaller uncertainties
in the mass extraction and to a reduced correlation of the mass and the strong
coupling. We arrive at $M_b^{1S}=4.71\pm 0.03$ GeV taking
$\alpha_s(M_Z)=0.118\pm 0.004$ as an input. From that we determine the
$\bar{MS}$ mass as $\bar m_b(\bar m_b) = 4.20 \pm 0.06$ GeV. The error in $\bar
m_b(\bar m_b)$ can be reduced if the three-loop corrections to the relation of
pole and $\bar{MS}$ mass are known and if the error in the strong coupling is
decreased.
| [
{
"created": "Sun, 30 May 1999 22:34:33 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Jun 1999 16:21:33 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Hoang",
"A. H.",
"",
"CERN"
]
] | The bottom quark 1S mass, $M_b^{1S}$, is determined using sum rules which relate the masses and the electronic decay widths of the $\Upsilon$ mesons to moments of the vacuum polarization function. The 1S mass is defined as half the perturbative mass of a fictitious ${}^3S_1$ bottom-antibottom quark bound state, and is free of the ambiguity of order $\Lambda_{QCD}$ which plagues the pole mass definition. Compared to an earlier analysis by the same author, which had been carried out in the pole mass scheme, the 1S mass scheme leads to a much better behaved perturbative series of the moments, smaller uncertainties in the mass extraction and to a reduced correlation of the mass and the strong coupling. We arrive at $M_b^{1S}=4.71\pm 0.03$ GeV taking $\alpha_s(M_Z)=0.118\pm 0.004$ as an input. From that we determine the $\bar{MS}$ mass as $\bar m_b(\bar m_b) = 4.20 \pm 0.06$ GeV. The error in $\bar m_b(\bar m_b)$ can be reduced if the three-loop corrections to the relation of pole and $\bar{MS}$ mass are known and if the error in the strong coupling is decreased. |
2104.13548 | Hai-Yang Cheng | Hai-Yang Cheng, Cheng-Wei Chiang | CP violation in quasi-two-body $D\to VP$ decays and three-body $D$
decays mediated by vector resonances | 36 pages, 5 figures, 5 reference added, published version in PRD | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We re-examine direct CP violation in the quasi-two-body $D\to V\!P$ decays
and study CP asymmetries in three-body $D$ decays proceeding through
intermediate vector resonances within the framework of the topological
amplitude approach for tree amplitudes and the QCD factorization approach for
penguin amplitudes. Using the same mechanism of incorporating long-distance
penguin-exchange amplitude induced from final-state rescattering that nicely
accounts for the CP asymmetry difference between $D^0\to K^+K^-$ and
$\pi^+\pi^-$ modes, we find that CP asymmetry can also occur at the per mille
level in many of the $D\to V\!P$ channels or otherwise be negligibly small. We
point out six golden modes which have sufficiently large branching fractions
and direct CP violation of order $10^{-3}$. In particular, the direct CP
asymmetry difference $\Delta a_{CP}^{V\!P}$ between $D^0\to K^+K^{*-}$ and
$\pi^+\rho^-$ is predicted to be $(-1.61\pm0.33)\times 10^{-3}$, very similar
to the counterpart in the $P\!P$ sector. Besides, we find a positive and large
CP asymmetry of order $10^{-3}$ in $D^0\to K_S K^{*0}$, an example of the
asymmetry induced at the tree level. We take into account the flavor-singlet
QCD-penguin contributions to calculate their effects on the modes such as
$D\to\pi\phi$ and $D\to \eta \phi$. We compare our results with the other
approach in detail. For three-body $D$ decays, we perform the Dalitz plot
analysis of those decays mediated by several vector resonances with the same
mass but different electric charges. Local CP asymmetry varies in magnitude and
sign from region to region and can reach the percent level in certain local
regions of phase space due to interference.
| [
{
"created": "Wed, 28 Apr 2021 02:54:44 GMT",
"version": "v1"
},
{
"created": "Fri, 30 Apr 2021 06:10:18 GMT",
"version": "v2"
},
{
"created": "Sun, 5 Sep 2021 21:00:25 GMT",
"version": "v3"
}
] | 2021-09-07 | [
[
"Cheng",
"Hai-Yang",
""
],
[
"Chiang",
"Cheng-Wei",
""
]
] | We re-examine direct CP violation in the quasi-two-body $D\to V\!P$ decays and study CP asymmetries in three-body $D$ decays proceeding through intermediate vector resonances within the framework of the topological amplitude approach for tree amplitudes and the QCD factorization approach for penguin amplitudes. Using the same mechanism of incorporating long-distance penguin-exchange amplitude induced from final-state rescattering that nicely accounts for the CP asymmetry difference between $D^0\to K^+K^-$ and $\pi^+\pi^-$ modes, we find that CP asymmetry can also occur at the per mille level in many of the $D\to V\!P$ channels or otherwise be negligibly small. We point out six golden modes which have sufficiently large branching fractions and direct CP violation of order $10^{-3}$. In particular, the direct CP asymmetry difference $\Delta a_{CP}^{V\!P}$ between $D^0\to K^+K^{*-}$ and $\pi^+\rho^-$ is predicted to be $(-1.61\pm0.33)\times 10^{-3}$, very similar to the counterpart in the $P\!P$ sector. Besides, we find a positive and large CP asymmetry of order $10^{-3}$ in $D^0\to K_S K^{*0}$, an example of the asymmetry induced at the tree level. We take into account the flavor-singlet QCD-penguin contributions to calculate their effects on the modes such as $D\to\pi\phi$ and $D\to \eta \phi$. We compare our results with the other approach in detail. For three-body $D$ decays, we perform the Dalitz plot analysis of those decays mediated by several vector resonances with the same mass but different electric charges. Local CP asymmetry varies in magnitude and sign from region to region and can reach the percent level in certain local regions of phase space due to interference. |
0707.1259 | Dani\"el Boer | Daniel Boer, Delia Hasch, Gerhard Mallot | Spin Physics: Session Summary | 16 pages, 29 eps figures, uses dis07.cls, summary of the Spin Physics
Working Group of the 15th International Workshop on Deep-Inelastic Scattering
and Related Subjects (DIS2007), Munich, Germany, 16-20 April 2007 | null | null | null | hep-ph hep-ex | null | We summarize the main results of the spin physics Working Group Session of
DIS 2007, the 15th International Workshop on ``Deep-Inelastic Scattering and
Related Subjects''.
| [
{
"created": "Mon, 9 Jul 2007 14:59:20 GMT",
"version": "v1"
},
{
"created": "Wed, 11 Jul 2007 15:36:17 GMT",
"version": "v2"
}
] | 2011-11-10 | [
[
"Boer",
"Daniel",
""
],
[
"Hasch",
"Delia",
""
],
[
"Mallot",
"Gerhard",
""
]
] | We summarize the main results of the spin physics Working Group Session of DIS 2007, the 15th International Workshop on ``Deep-Inelastic Scattering and Related Subjects''. |
2203.05536 | Animesh Barman | Animesh Barman, Ng. K. Francis, Bikash Thapa, and Ankur Nath | Non-zero $\theta_{13}$, CP-violation and Neutrinoless Double Beta Decay
for Neutrino Mixing in the $A_4\times Z_2\times Z_3$ Flavor Symmetry Model | 19 pages, 6 figures, 3 tables | null | 10.1142/S0217751X23500124 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We study the modification of the Altarelli-Feruglio $A_4$ flavor symmetry
model by adding three singlet flavons $\xi'$, $\xi''$ and $\rho$ and the model
is augmented with extra $Z_2\times Z_2^ \prime$ symmetry to prevent the
unwanted terms in our study. The addition of these three flavons lead to two
higher order corrections in the form of two perturbation parameters $\epsilon$
and $\epsilon^\prime$. These corrections yield the deviation from exact
tri-bimaximal (TBM) neutrino mixing pattern by producing a non-zero
$\theta_{13}$ and other neutrino oscillation parameters which are consistent
with the latest experimental data. In both the corrections, the neutrino masses
are generated via Weinberg operator. The analysis of the perturbation
parameters $\epsilon$ and $\epsilon^\prime$, shows that normal hierarchy (NH)
and inverted hierarchy (IH) for $\epsilon$ does not change much. However, as
the values of $\epsilon^\prime$ increases, $\theta_{23}$ occupies the lower
octant for NH case. We further investigate the neutrinoless double beta decay
parmeter $m_{\beta\beta}$ using the parameter space of the model for both
normal and inverted hierarchies of neutrino masses.
| [
{
"created": "Thu, 10 Mar 2022 18:40:56 GMT",
"version": "v1"
},
{
"created": "Tue, 29 Mar 2022 07:38:01 GMT",
"version": "v2"
},
{
"created": "Sun, 26 Feb 2023 08:41:01 GMT",
"version": "v3"
}
] | 2023-02-28 | [
[
"Barman",
"Animesh",
""
],
[
"Francis",
"Ng. K.",
""
],
[
"Thapa",
"Bikash",
""
],
[
"Nath",
"Ankur",
""
]
] | We study the modification of the Altarelli-Feruglio $A_4$ flavor symmetry model by adding three singlet flavons $\xi'$, $\xi''$ and $\rho$ and the model is augmented with extra $Z_2\times Z_2^ \prime$ symmetry to prevent the unwanted terms in our study. The addition of these three flavons lead to two higher order corrections in the form of two perturbation parameters $\epsilon$ and $\epsilon^\prime$. These corrections yield the deviation from exact tri-bimaximal (TBM) neutrino mixing pattern by producing a non-zero $\theta_{13}$ and other neutrino oscillation parameters which are consistent with the latest experimental data. In both the corrections, the neutrino masses are generated via Weinberg operator. The analysis of the perturbation parameters $\epsilon$ and $\epsilon^\prime$, shows that normal hierarchy (NH) and inverted hierarchy (IH) for $\epsilon$ does not change much. However, as the values of $\epsilon^\prime$ increases, $\theta_{23}$ occupies the lower octant for NH case. We further investigate the neutrinoless double beta decay parmeter $m_{\beta\beta}$ using the parameter space of the model for both normal and inverted hierarchies of neutrino masses. |
1111.0528 | Antonio Delgado | Antonio Delgado and Mariano Quiros | The Least Supersymmetric Standard Model | 12 pages, 1 figure | null | 10.1103/PhysRevD.85.015001 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose the minimal (Least) version of the Supersymmetric Standard Model
which can solve the hierarchy problem in the same way as the so-called Minimal
Supersymmetric Standard Model (MSSM) and presents solutions to some of its
problems. Supersymmetry is broken in a secluded sector and mediated to the
observable sector by messengers of a gauge group G under which the first two
generations transform. The group G spontaneously breaks (almost)
supersymmetrically at a scale at most a few orders of magnitude below the scale
of gauge messengers M_*\sim 10^{15} GeV. By gauge mediation sfermions of the
first two generations acquire supersymmetry breaking masses \hat m \sim 10 TeV.
Supersymmetry breaking is also mediated by gravity which generates masses for
all sfermions, Higgsinos and gauginos at the TeV scale and can provide
appropriate values to the \mu and B_\mu parameters by D-term effective
operators. If gravity mediation is Minimal Flavor Violating there is no
supersymmetric flavor problem. In the presence of R-parity dark matter can be
the lightest neutralino, as in the MSSM, and the LHC model phenomenology is
characterized by the fact that only third generation squarks and sleptons are
present.
| [
{
"created": "Wed, 2 Nov 2011 15:11:54 GMT",
"version": "v1"
}
] | 2013-05-30 | [
[
"Delgado",
"Antonio",
""
],
[
"Quiros",
"Mariano",
""
]
] | We propose the minimal (Least) version of the Supersymmetric Standard Model which can solve the hierarchy problem in the same way as the so-called Minimal Supersymmetric Standard Model (MSSM) and presents solutions to some of its problems. Supersymmetry is broken in a secluded sector and mediated to the observable sector by messengers of a gauge group G under which the first two generations transform. The group G spontaneously breaks (almost) supersymmetrically at a scale at most a few orders of magnitude below the scale of gauge messengers M_*\sim 10^{15} GeV. By gauge mediation sfermions of the first two generations acquire supersymmetry breaking masses \hat m \sim 10 TeV. Supersymmetry breaking is also mediated by gravity which generates masses for all sfermions, Higgsinos and gauginos at the TeV scale and can provide appropriate values to the \mu and B_\mu parameters by D-term effective operators. If gravity mediation is Minimal Flavor Violating there is no supersymmetric flavor problem. In the presence of R-parity dark matter can be the lightest neutralino, as in the MSSM, and the LHC model phenomenology is characterized by the fact that only third generation squarks and sleptons are present. |
hep-ph/0107183 | Massimo Blasone | Massimo Blasone, Antonio Capolupo, Giuseppe Vitiello | Comment on ``Remarks on flavor-neutrino propagators and oscillation
formulae'' | 4 pages, RevTeX | null | null | null | hep-ph | null | We comment on the paper ``Remarks on flavor-neutrino propagators and
oscillation formulae'' [Phys. Rev. D64, 013011 (2001)].
We show that the conclusions presented in that paper do not apply to the
exact field theoretical oscillation formulae obtained in the BV formalism (for
three flavors) which are free from the dependence on arbitrary mass parameters,
account for CP violation and reduce to the usual quantum mechanical
(Pontecorvo) three flavor oscillation formulae in the relativistic limit.
| [
{
"created": "Tue, 17 Jul 2001 03:26:13 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Blasone",
"Massimo",
""
],
[
"Capolupo",
"Antonio",
""
],
[
"Vitiello",
"Giuseppe",
""
]
] | We comment on the paper ``Remarks on flavor-neutrino propagators and oscillation formulae'' [Phys. Rev. D64, 013011 (2001)]. We show that the conclusions presented in that paper do not apply to the exact field theoretical oscillation formulae obtained in the BV formalism (for three flavors) which are free from the dependence on arbitrary mass parameters, account for CP violation and reduce to the usual quantum mechanical (Pontecorvo) three flavor oscillation formulae in the relativistic limit. |
2305.13950 | Vipul Bairathi Dr. | P. Sinha, V. Bairathi, K. Gopal, C. Jena, and S. Kabana | Effect of nuclear structure on particle production in relativistic
heavy-ion collisions using the AMPT model | 14 pages, 9 figures | null | 10.1103/PhysRevC.108.024911 | null | hep-ph hep-ex nucl-ex | http://creativecommons.org/licenses/by/4.0/ | We report first study of transverse momentum ($p_\mathrm{T}$) spectra for
$\pi^{\pm}$, $K^{\pm}$, $p$, and $\bar{p}$ in isobar,
$^{96}_{44}$Ru+$^{96}_{44}$Ru and $^{96}_{40}$Zr+$^{96}_{40}$Zr, collisions at
$\sqrt{s_{\mathrm{NN}}} = 200$ GeV using a multi-phase transport (AMPT) model.
Particle yields ($dN/dy$), average transverse momenta ($\langle p_\mathrm{T}
\rangle$), and particle ratios are reported in various collision systems with
different parameterizations of the Woods-Saxon (WS) distribution. We observed a
maximum difference of 5% in the particle yields in peripheral collisions when
we included a quadrupole and octupole deformation and a nuclear size difference
between the isobars. The $\pi^{-}$/$\pi^{+}$ ratio is smaller in Ru+Ru
collisions compared to Zr+Zr collisions indicating an effect of isospin due to
difference in number of protons and neutrons between the two nuclei. The
$K^{-}$/$K^{+}$ ratio is same in both the systems indicating the dominance of
the pair production mechanism in the kaon production. The $\bar{p}/p$ ratio is
further smaller in Ru+Ru collisions than Zr+Zr collisions, indicating the
effect of baryon stopping in addition to the isospin effect. A system size
dependence is observed in $dN/dy$ and $\langle p_\mathrm{T} \rangle$ when we
compare the results from isobar collisions with Au+Au and U+U collisions.
| [
{
"created": "Tue, 23 May 2023 11:19:38 GMT",
"version": "v1"
},
{
"created": "Wed, 10 Jul 2024 01:53:50 GMT",
"version": "v2"
}
] | 2024-07-11 | [
[
"Sinha",
"P.",
""
],
[
"Bairathi",
"V.",
""
],
[
"Gopal",
"K.",
""
],
[
"Jena",
"C.",
""
],
[
"Kabana",
"S.",
""
]
] | We report first study of transverse momentum ($p_\mathrm{T}$) spectra for $\pi^{\pm}$, $K^{\pm}$, $p$, and $\bar{p}$ in isobar, $^{96}_{44}$Ru+$^{96}_{44}$Ru and $^{96}_{40}$Zr+$^{96}_{40}$Zr, collisions at $\sqrt{s_{\mathrm{NN}}} = 200$ GeV using a multi-phase transport (AMPT) model. Particle yields ($dN/dy$), average transverse momenta ($\langle p_\mathrm{T} \rangle$), and particle ratios are reported in various collision systems with different parameterizations of the Woods-Saxon (WS) distribution. We observed a maximum difference of 5% in the particle yields in peripheral collisions when we included a quadrupole and octupole deformation and a nuclear size difference between the isobars. The $\pi^{-}$/$\pi^{+}$ ratio is smaller in Ru+Ru collisions compared to Zr+Zr collisions indicating an effect of isospin due to difference in number of protons and neutrons between the two nuclei. The $K^{-}$/$K^{+}$ ratio is same in both the systems indicating the dominance of the pair production mechanism in the kaon production. The $\bar{p}/p$ ratio is further smaller in Ru+Ru collisions than Zr+Zr collisions, indicating the effect of baryon stopping in addition to the isospin effect. A system size dependence is observed in $dN/dy$ and $\langle p_\mathrm{T} \rangle$ when we compare the results from isobar collisions with Au+Au and U+U collisions. |
1109.2180 | Zhi-Gang Wang | Zhi-Gang Wang | Analysis of the $\Sigma_Q$ baryons in the nuclear matter with the QCD
sum rules | 7 pages, 2 figures, revised version | Phys. Rev. C85 (2012) 045204 | 10.1103/PhysRevC.85.045204 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this article, we extend our previous work to study the $\Sigma$-type heavy
baryons $\Sigma_c$ and $\Sigma_b$ in the nuclear matter using the QCD sum
rules, and obtain three coupled QCD sum rules for the masses $M_{\Sigma_Q}^*$,
vector self-energies $\Sigma_v$ and pole residues $\lambda^*_{\Sigma_Q}$ in the
nuclear matter. Then we take into account the effects of the unequal pole
residues from different spinor structures, and normalize the masses from the
QCD sum rules in the vacuum to the experimental data, and obtain the
mass-shifts $\delta M_{\Sigma_c}=-123\,\rm{MeV}$ and $\delta
M_{\Sigma_b}=-375\,\rm{MeV}$ in the nuclear matter.
| [
{
"created": "Sat, 10 Sep 2011 01:19:44 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Jan 2012 13:59:00 GMT",
"version": "v2"
},
{
"created": "Tue, 6 Mar 2012 03:54:57 GMT",
"version": "v3"
}
] | 2012-04-17 | [
[
"Wang",
"Zhi-Gang",
""
]
] | In this article, we extend our previous work to study the $\Sigma$-type heavy baryons $\Sigma_c$ and $\Sigma_b$ in the nuclear matter using the QCD sum rules, and obtain three coupled QCD sum rules for the masses $M_{\Sigma_Q}^*$, vector self-energies $\Sigma_v$ and pole residues $\lambda^*_{\Sigma_Q}$ in the nuclear matter. Then we take into account the effects of the unequal pole residues from different spinor structures, and normalize the masses from the QCD sum rules in the vacuum to the experimental data, and obtain the mass-shifts $\delta M_{\Sigma_c}=-123\,\rm{MeV}$ and $\delta M_{\Sigma_b}=-375\,\rm{MeV}$ in the nuclear matter. |
1804.01803 | Mainak Chakraborty | Biswonath Sahoo, Mainak Chakraborty, M.K. Parida (Siksha 'O'
Anusandhan) | Neutrino Mass, Coupling Unification, Verifiable Proton Decay, Vacuum
Stability and WIMP Dark Matter in SU(5) | 36 pages, 9 figures (Accepted for publication in Advances in High
Energy Physics) | Advances in High Energy Physics (2018) | 10.1155/2018/4078657 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Nonsupersymmetric minimal SU(5) with Higgs representations ${24}_H$ and $5_H$
and standard fermions in ${\bar 5}_F\oplus {10}_F$ is well known for its
failure in unification of gauge couplings and lack of predicting neutrino
masses. Like standard model, it is also affected by the instability of the
Higgs scalar potential. We note that extending the Higgs sector by ${75}_H$ and
${15}_H$ not only leads to the popular type-II seesaw ansatz for neutrino
masses with a lower bound on the triplet mass $M_{\Delta} > 2\times 10^9$ GeV,
but also achieves precision unification of gauge couplings without
proliferation of non-standard light Higgs scalars or fermions near the TeV
scale. Consistent with recent LUX-2016 lower bound, the model easily
accommodates a singlet scalar WIMP dark matter near the TeV scale which
resolves the vacuum stability issue even after inclusion of heavy triplet
threshold effect. We estimate proton lifetime predictions for $p\to e^+\pi^0$
including uncertainties due to input parameters and threshold effects due to
superheavy Higgs scalars and superheavy $X^{\pm 4/3},Y^{\pm 1/3}$ gauge bosons.
The predicted lifetime is noted to be verifiable at Super Kamiokande and Hyper
Kamiokande experiments.
| [
{
"created": "Thu, 5 Apr 2018 12:27:07 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Jul 2018 17:17:45 GMT",
"version": "v2"
}
] | 2018-08-09 | [
[
"Sahoo",
"Biswonath",
"",
"Siksha 'O'\n Anusandhan"
],
[
"Chakraborty",
"Mainak",
"",
"Siksha 'O'\n Anusandhan"
],
[
"Parida",
"M. K.",
"",
"Siksha 'O'\n Anusandhan"
]
] | Nonsupersymmetric minimal SU(5) with Higgs representations ${24}_H$ and $5_H$ and standard fermions in ${\bar 5}_F\oplus {10}_F$ is well known for its failure in unification of gauge couplings and lack of predicting neutrino masses. Like standard model, it is also affected by the instability of the Higgs scalar potential. We note that extending the Higgs sector by ${75}_H$ and ${15}_H$ not only leads to the popular type-II seesaw ansatz for neutrino masses with a lower bound on the triplet mass $M_{\Delta} > 2\times 10^9$ GeV, but also achieves precision unification of gauge couplings without proliferation of non-standard light Higgs scalars or fermions near the TeV scale. Consistent with recent LUX-2016 lower bound, the model easily accommodates a singlet scalar WIMP dark matter near the TeV scale which resolves the vacuum stability issue even after inclusion of heavy triplet threshold effect. We estimate proton lifetime predictions for $p\to e^+\pi^0$ including uncertainties due to input parameters and threshold effects due to superheavy Higgs scalars and superheavy $X^{\pm 4/3},Y^{\pm 1/3}$ gauge bosons. The predicted lifetime is noted to be verifiable at Super Kamiokande and Hyper Kamiokande experiments. |
2011.14933 | Benoit Assi | B. Assi, B.A. Kniehl | Electroweak Form Factor in Sudakov and Threshold Regimes with Effective
Field Theories | 80 pages, 11 figures. arXiv admin note: text overlap with
arXiv:0712.0396, arXiv:hep-ph/0603133 by other authors | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We compute the massive gauge and scalar corrections to form factors in both
the Sudakov and threshold regimes up to and including two-loop orders. The
corrections are calculated for processes involving two external fermions and
scalars in the spontaneously broken SU(N)-Higgs model, examining a range of
composite operators. Our results are general, so we discuss how our form
factors are mappable from our model to the Standard Model and beyond. The
effective theory formalism deployed in our work extends previous studies based
on infrared evolution equations, which either neglect scalar contributions or
are restricted to the Sudakov regime.
| [
{
"created": "Mon, 16 Nov 2020 00:01:39 GMT",
"version": "v1"
}
] | 2020-12-01 | [
[
"Assi",
"B.",
""
],
[
"Kniehl",
"B. A.",
""
]
] | We compute the massive gauge and scalar corrections to form factors in both the Sudakov and threshold regimes up to and including two-loop orders. The corrections are calculated for processes involving two external fermions and scalars in the spontaneously broken SU(N)-Higgs model, examining a range of composite operators. Our results are general, so we discuss how our form factors are mappable from our model to the Standard Model and beyond. The effective theory formalism deployed in our work extends previous studies based on infrared evolution equations, which either neglect scalar contributions or are restricted to the Sudakov regime. |
hep-ph/9808393 | Thomas Binoth | T. Binoth (Lab. d'Annecy-le-Vieux de Physique Theorique), A. Ghinculov
(Univ. of Michigan) | New developments in the 1/N expansion and nonperturbative Higgs physics | 23 pages, latex, eps-figures included | Nucl.Phys. B550 (1999) 77-98 | 10.1016/S0550-3213(99)00189-3 | LAPTH-692-98, UM-TH 98-12, CERN-TH/98-244 | hep-ph | null | We show in this paper that the 1/N expansion is a reliable tool to calculate
the properties of a heavy Higgs boson. The 1/N expansion sums up all orders in
perturbation theory, and therefore avoids the renormalization scheme dependence
of the conventional perturbative approach. It is explained how effects due to
the Landau pole of the Higgs sector are isolated and subtracted, and how to
perform actual calculations, by computing the Higgs line shape for the
processes f\bar f\to H \to ZZ,f'\bar f' at next-to-leading order in the 1/N
expansion. The results are compared to the perturbative results to show the
agreement between the perturbative and the nonperturbative approach for Higgs
masses up to 1 TeV. We conclude that the theoretical predictions for Higgs
observables are well under control for the entire kinematical region of the
LHC.
| [
{
"created": "Mon, 24 Aug 1998 15:34:37 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Binoth",
"T.",
"",
"Lab. d'Annecy-le-Vieux de Physique Theorique"
],
[
"Ghinculov",
"A.",
"",
"Univ. of Michigan"
]
] | We show in this paper that the 1/N expansion is a reliable tool to calculate the properties of a heavy Higgs boson. The 1/N expansion sums up all orders in perturbation theory, and therefore avoids the renormalization scheme dependence of the conventional perturbative approach. It is explained how effects due to the Landau pole of the Higgs sector are isolated and subtracted, and how to perform actual calculations, by computing the Higgs line shape for the processes f\bar f\to H \to ZZ,f'\bar f' at next-to-leading order in the 1/N expansion. The results are compared to the perturbative results to show the agreement between the perturbative and the nonperturbative approach for Higgs masses up to 1 TeV. We conclude that the theoretical predictions for Higgs observables are well under control for the entire kinematical region of the LHC. |
1311.5149 | Aaron Higuera | A. Higuera, E. A. Paschos | Angular Dependence of Coherent Pion Production by Neutrinos | 10 pages, 4 figures | Eur. Phys. J. Plus (2014) 129: 43 | 10.1140/epjp/i2014-14043-1 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Coherent pion production by neutrinos has been interpreted in the framework
of the Partially Conserved Axial Current hypothesis (PCAC) and explicit model
calculations are available. In this article we compute angular correlations for
the produced pions which may help to separate the signal from the background.
We present many figures useful for the experiments and compare them with
another model.
| [
{
"created": "Wed, 20 Nov 2013 18:00:17 GMT",
"version": "v1"
},
{
"created": "Tue, 28 Jan 2014 18:37:57 GMT",
"version": "v2"
}
] | 2014-03-18 | [
[
"Higuera",
"A.",
""
],
[
"Paschos",
"E. A.",
""
]
] | Coherent pion production by neutrinos has been interpreted in the framework of the Partially Conserved Axial Current hypothesis (PCAC) and explicit model calculations are available. In this article we compute angular correlations for the produced pions which may help to separate the signal from the background. We present many figures useful for the experiments and compare them with another model. |
hep-ph/9809473 | James A. McNeil | T. S. T. Aly and J. A. McNeil | Chiral baryon in the coherent pair approximation | RevTeX, 24 pages, 5 figures | Phys. Rev. D 60, 114022 (1999) | 10.1103/PhysRevD.60.114022 | null | hep-ph | null | We revisit the work of K. Goeke, M. Harvey, F. Gr\"ummer, and J. N. Urbano
(Phys. Rev. {\bf D37}, 754 (1988)) who considered a chiral model for the
nucleon based on the linear sigma model with scalar-isoscalar scalar-isovector
mesons coupled to quarks and solved using the coherent-pair approximation. In
this way the quantum pion field can be treated in a non-perturbative fashion.
In this work we review this model and the coherent pair approximation
correcting several errors in the earlier work. We minimize the expectation
value of the chiral hamiltonian in the ansatz coherent-pair ground state
configuration and solve the resulting equations for nucleon quantum numbers. We
calculate the canonical set of nucleon observables and compare with the
Hedgehog model and experiment. Using the corrected equations yield slightly
different values for nucleon observables but do not correct the large virial
deviation in the $\pi$-nucleon coupling. Our results therefore do not
significantly alter the conclusions of Goeke, et al..
| [
{
"created": "Mon, 21 Sep 1998 22:15:46 GMT",
"version": "v1"
}
] | 2016-08-25 | [
[
"Aly",
"T. S. T.",
""
],
[
"McNeil",
"J. A.",
""
]
] | We revisit the work of K. Goeke, M. Harvey, F. Gr\"ummer, and J. N. Urbano (Phys. Rev. {\bf D37}, 754 (1988)) who considered a chiral model for the nucleon based on the linear sigma model with scalar-isoscalar scalar-isovector mesons coupled to quarks and solved using the coherent-pair approximation. In this way the quantum pion field can be treated in a non-perturbative fashion. In this work we review this model and the coherent pair approximation correcting several errors in the earlier work. We minimize the expectation value of the chiral hamiltonian in the ansatz coherent-pair ground state configuration and solve the resulting equations for nucleon quantum numbers. We calculate the canonical set of nucleon observables and compare with the Hedgehog model and experiment. Using the corrected equations yield slightly different values for nucleon observables but do not correct the large virial deviation in the $\pi$-nucleon coupling. Our results therefore do not significantly alter the conclusions of Goeke, et al.. |
2204.08815 | Vladimir A. Petrov | Vladimir Petrov (1), Nikolai Tkachenko (1) ((1) A.A. Logunov Institute
for High Energy Physics, NRC "Kurchatov Institute", Protvino, Russia) | Coulomb-Nuclear Interference: Theory and Practice for pp-Scattering at
13 TeV | 24 pages, 11 figures | null | 10.1103/PhysRevD.106.054003 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We provide a detailed reconsideration of the theoretical basis for the
treatment of Coulomb-nuclear interference (CNI) and a corresponding thorough
analysis of the procedure of extraction of the basic parameters $\rho^{~pp},
\sigma_{tot}^{~pp}$ and $B^{~pp}$ from the TOTEM data at $\sqrt{s} = 13$ TeV. A
more substantiated account of CNI, as well as an in-depth statistical analysis
of the TOTEM data at low transferred momenta, give results that differ from
those published by the TOTEM collaboration.
| [
{
"created": "Tue, 19 Apr 2022 11:31:25 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Apr 2022 12:31:46 GMT",
"version": "v2"
},
{
"created": "Fri, 13 May 2022 13:40:25 GMT",
"version": "v3"
}
] | 2022-09-21 | [
[
"Petrov",
"Vladimir",
""
],
[
"Tkachenko",
"Nikolai",
""
]
] | We provide a detailed reconsideration of the theoretical basis for the treatment of Coulomb-nuclear interference (CNI) and a corresponding thorough analysis of the procedure of extraction of the basic parameters $\rho^{~pp}, \sigma_{tot}^{~pp}$ and $B^{~pp}$ from the TOTEM data at $\sqrt{s} = 13$ TeV. A more substantiated account of CNI, as well as an in-depth statistical analysis of the TOTEM data at low transferred momenta, give results that differ from those published by the TOTEM collaboration. |
hep-ph/0405139 | Anna Maria Rotunno | G.L. Fogli, E. Lisi, A. Palazzo, and A.M. Rotunno (Dipartimento di
Fisica di Bari and Sezione INFN di Bari) | Geoneutrino Analysis in KamLAND: Input and Desiderata | 6 pages, 4 figures. Talk given at 39th Rencontres de Moriond on
Electronweack Interactions and Unified Theories, La Thuile, Italy, 21-28 Mar
2004 | null | null | null | hep-ph | null | The Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) is
collecting antineutrino events generated by nuclear reactors and by Thorium and
Uranium decay in the Earth interior. We comment on a systematic approach to the
evaluation of the geo-neutrino contribution and of its uncertainties in
KamLAND, taking into account geophysical and geochemical indications,
estimates, and data. The results can help to improve both the neutrino
oscillation analysis and the knowledge of the Earth interior. Input and
desiderata for future geoneutrino analyses are identified.
| [
{
"created": "Fri, 14 May 2004 17:12:21 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Fogli",
"G. L.",
"",
"Dipartimento di\n Fisica di Bari and Sezione INFN di Bari"
],
[
"Lisi",
"E.",
"",
"Dipartimento di\n Fisica di Bari and Sezione INFN di Bari"
],
[
"Palazzo",
"A.",
"",
"Dipartimento di\n Fisica di Bari and Sezione INFN di Bari"
],... | The Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) is collecting antineutrino events generated by nuclear reactors and by Thorium and Uranium decay in the Earth interior. We comment on a systematic approach to the evaluation of the geo-neutrino contribution and of its uncertainties in KamLAND, taking into account geophysical and geochemical indications, estimates, and data. The results can help to improve both the neutrino oscillation analysis and the knowledge of the Earth interior. Input and desiderata for future geoneutrino analyses are identified. |
2202.00985 | Chandan Mondal | Yiping Liu, Siqi Xu, Chandan Mondal, Xingbo Zhao, James P. Vary | Angular momentum and generalized parton distributions for the proton
with basis light-front quantization | 14 pages, 4 figures | null | 10.1103/PhysRevD.105.094018 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We study the unpolarized and the helicity dependent generalized parton
distributions (GPDs) for the valence quarks of the proton in both momentum
space and position space within the basis light-front quantization (BLFQ)
framework. The GPDs for the valence quarks are computed from the eigenvectors
of a light-front effective Hamiltonian in the valence Fock sector consisting of
a three-dimensional confinement potential and a one-gluon exchange interaction
with fixed coupling. Employing these GPDs, we obtain the spatial distributions
of quark angular momentum inside the proton. In our BLFQ approach, we explore
various definitions of angular momentum density and illustrate the differences
between them arising from terms that integrate to zero. We also discuss the
flavor contributions to the quark angular momentum densities.
| [
{
"created": "Wed, 2 Feb 2022 12:10:34 GMT",
"version": "v1"
}
] | 2022-06-01 | [
[
"Liu",
"Yiping",
""
],
[
"Xu",
"Siqi",
""
],
[
"Mondal",
"Chandan",
""
],
[
"Zhao",
"Xingbo",
""
],
[
"Vary",
"James P.",
""
]
] | We study the unpolarized and the helicity dependent generalized parton distributions (GPDs) for the valence quarks of the proton in both momentum space and position space within the basis light-front quantization (BLFQ) framework. The GPDs for the valence quarks are computed from the eigenvectors of a light-front effective Hamiltonian in the valence Fock sector consisting of a three-dimensional confinement potential and a one-gluon exchange interaction with fixed coupling. Employing these GPDs, we obtain the spatial distributions of quark angular momentum inside the proton. In our BLFQ approach, we explore various definitions of angular momentum density and illustrate the differences between them arising from terms that integrate to zero. We also discuss the flavor contributions to the quark angular momentum densities. |
1606.02696 | Artem Lipatov | A.V. Lipatov, M.A. Malyshev | Reconsideration of the inclusive prompt photon production at LHC with
kt-factorization | 13 pages, 7 figures | Phys. Rev. D 94, 034020 (2016) | 10.1103/PhysRevD.94.034020 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We reconsider the inclusive production of isolated prompt photons in $pp$
collisions at the LHC energies in the framework of $k_T$-factorization
approach. Our analysis is based on the ${\cal O}(\alpha \alpha_s)$ off-shell
(depending on the transverse momenta of initial quarks and gluons) production
amplitudes of $q^* g^* \to \gamma q$ and $q^* \bar q^* \to \gamma g$ partonic
subprocesses and transverse momentum dependent (or unintegrated) quark and
gluon densities in a proton, which are chosen in accordance with the
Kimber-Martin-Ryskin prescription. We show that the sub-leading high-order
${\cal O}(\alpha \alpha_s^2)$ contributions, not covered by the non-collinear
evolution of parton densities, are important to describe latest LHC data.
| [
{
"created": "Wed, 8 Jun 2016 19:27:34 GMT",
"version": "v1"
},
{
"created": "Tue, 2 Aug 2016 17:51:19 GMT",
"version": "v2"
}
] | 2016-08-17 | [
[
"Lipatov",
"A. V.",
""
],
[
"Malyshev",
"M. A.",
""
]
] | We reconsider the inclusive production of isolated prompt photons in $pp$ collisions at the LHC energies in the framework of $k_T$-factorization approach. Our analysis is based on the ${\cal O}(\alpha \alpha_s)$ off-shell (depending on the transverse momenta of initial quarks and gluons) production amplitudes of $q^* g^* \to \gamma q$ and $q^* \bar q^* \to \gamma g$ partonic subprocesses and transverse momentum dependent (or unintegrated) quark and gluon densities in a proton, which are chosen in accordance with the Kimber-Martin-Ryskin prescription. We show that the sub-leading high-order ${\cal O}(\alpha \alpha_s^2)$ contributions, not covered by the non-collinear evolution of parton densities, are important to describe latest LHC data. |
hep-ph/9501382 | null | Ken-ichi Hikasa and Yumi Nakamura | Soft-breaking correction to hard supersymmetric relations: QCD
correction to squark decay | 12 pages plus 5 figures, macros included | Z.Phys. C70 (1996) 139-144; Erratum-ibid. C71 (1996) 356 | 10.1007/BF02906995 | TU-475 | hep-ph | null | Supersymmetric relations between dimensionless couplings receive finite
correction at one-loop when supersymmetry is broken softly. We calculate the
$O(\alpha_s)$ correction to the squark decay width to a quark and an
electroweak gaugino, which is found to be nonvanishing. Logarithmic correction
appears when the gluino is heavy.
| [
{
"created": "Thu, 26 Jan 1995 19:36:59 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Hikasa",
"Ken-ichi",
""
],
[
"Nakamura",
"Yumi",
""
]
] | Supersymmetric relations between dimensionless couplings receive finite correction at one-loop when supersymmetry is broken softly. We calculate the $O(\alpha_s)$ correction to the squark decay width to a quark and an electroweak gaugino, which is found to be nonvanishing. Logarithmic correction appears when the gluino is heavy. |
hep-ph/9507238 | Vid Jain | Vidyut Jain, Robert Shrock | U(1)$_A$ Models of Fermion Masses Without a $\mu$ Problem | 12 pages, Latex File | null | null | ITP-SB-95-22 | hep-ph | null | We discuss the connection between models of fermion masses and mixing
involving a string-motivated flavor/generation U(1)$_A$ gauge symmetry and the
$\mu$ term. We point out that in a certain class of such models the flavor
physics can provide an appealing solution to the $\mu$ problem, naturally
yielding a $\mu \sim O(m_{_W})$. A simple relationship between the $U(1)_A$
charge $q_{H}$ of the $\mu$-term and the average generational $U(1)_A$ charges
of the down quark and leptonic sectors is derived. Finally, we construct an
explicit model illustrating our results.
| [
{
"created": "Wed, 5 Jul 1995 21:20:03 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Jain",
"Vidyut",
""
],
[
"Shrock",
"Robert",
""
]
] | We discuss the connection between models of fermion masses and mixing involving a string-motivated flavor/generation U(1)$_A$ gauge symmetry and the $\mu$ term. We point out that in a certain class of such models the flavor physics can provide an appealing solution to the $\mu$ problem, naturally yielding a $\mu \sim O(m_{_W})$. A simple relationship between the $U(1)_A$ charge $q_{H}$ of the $\mu$-term and the average generational $U(1)_A$ charges of the down quark and leptonic sectors is derived. Finally, we construct an explicit model illustrating our results. |
hep-ph/0101079 | Sally Dawson | S. Dawson (BNL) and L. Reina (FSU) | Top Quark Yukawa Couplings and New Physics | Talk given at the 5th International Collider Workshop (LCWS 2000),
Fermilab, Batavia, Il, Oct 24-28, 2000 | null | 10.1063/1.1394318 | BNL-HET-01/1 | hep-ph | null | We discuss associated production of a Higgs boson with a pair of $t {\bar t}$
quarks at a future high energy $e^+e^-$ collider. The process $e^+e^-\to t
{\bar t}h$ is particularly sensitive to the presence of new physics and we
consider the MSSM and models with extra dimensions at the $TeV$ scale as
examples.
| [
{
"created": "Tue, 9 Jan 2001 15:06:44 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Dawson",
"S.",
"",
"BNL"
],
[
"Reina",
"L.",
"",
"FSU"
]
] | We discuss associated production of a Higgs boson with a pair of $t {\bar t}$ quarks at a future high energy $e^+e^-$ collider. The process $e^+e^-\to t {\bar t}h$ is particularly sensitive to the presence of new physics and we consider the MSSM and models with extra dimensions at the $TeV$ scale as examples. |
1810.04679 | Xing Wang | Tao Han, Hongkai Liu, Satyanarayan Mukhopadhyay, Xing Wang | Dark Matter Blind Spots at One-Loop | 20 pages, 5 figures; Minor corrections, references updated, version
published in JHEP | JHEP 1903 (2019) 080 | 10.1007/JHEP03(2019)080 | PITT-PACC-1815 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We evaluate the impact of one-loop electroweak corrections to the
spin-independent dark matter (DM) scattering cross-section with nucleons
($\sigma_{\rm SI}$), in models with a so-called blind spot for direct
detection, where the leading-order prediction for the relevant DM coupling to
the Higgs boson, and therefore $\sigma_{\rm SI}$, are vanishingly small.
Adopting a simple illustrative scenario in which the DM state results from the
mixing of electroweak singlet and doublet fermions, we compute the relevant
higher order corrections to the scalar effective operator contributions to
$\sigma_{\rm SI}$, stemming from both triangle and box diagrams involving the
SM and dark sector fields. It is observed that in a significant region of the
singlet-doublet model-space, the one-loop corrections ``unblind'' the
tree-level blind spots and lead to detectable SI scattering rates at future
multi-ton scale liquid Xenon experiments, with $\sigma_{\rm SI}$ reaching
values up to a few times $10^{-47} {~\rm cm}^2$, for a weak scale DM with
$\mathcal{O}(1)$ Yukawa couplings. Furthermore, we find that there always
exists a new SI blind spot at the next-to-leading order, which is
perturbatively shifted from the leading order one in the singlet-doublet mass
parameters. For comparison, we also present the tree-level spin-dependent
scattering cross-sections near the SI blind-spot region, that could lead to a
larger signal. Our results can be mapped to the blind-spot scenario for
bino-Higgsino DM in the MSSM, with other sfermions, the heavier Higgs boson,
and the wino decoupled.
| [
{
"created": "Wed, 10 Oct 2018 18:00:01 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Apr 2019 17:30:03 GMT",
"version": "v2"
}
] | 2019-04-15 | [
[
"Han",
"Tao",
""
],
[
"Liu",
"Hongkai",
""
],
[
"Mukhopadhyay",
"Satyanarayan",
""
],
[
"Wang",
"Xing",
""
]
] | We evaluate the impact of one-loop electroweak corrections to the spin-independent dark matter (DM) scattering cross-section with nucleons ($\sigma_{\rm SI}$), in models with a so-called blind spot for direct detection, where the leading-order prediction for the relevant DM coupling to the Higgs boson, and therefore $\sigma_{\rm SI}$, are vanishingly small. Adopting a simple illustrative scenario in which the DM state results from the mixing of electroweak singlet and doublet fermions, we compute the relevant higher order corrections to the scalar effective operator contributions to $\sigma_{\rm SI}$, stemming from both triangle and box diagrams involving the SM and dark sector fields. It is observed that in a significant region of the singlet-doublet model-space, the one-loop corrections ``unblind'' the tree-level blind spots and lead to detectable SI scattering rates at future multi-ton scale liquid Xenon experiments, with $\sigma_{\rm SI}$ reaching values up to a few times $10^{-47} {~\rm cm}^2$, for a weak scale DM with $\mathcal{O}(1)$ Yukawa couplings. Furthermore, we find that there always exists a new SI blind spot at the next-to-leading order, which is perturbatively shifted from the leading order one in the singlet-doublet mass parameters. For comparison, we also present the tree-level spin-dependent scattering cross-sections near the SI blind-spot region, that could lead to a larger signal. Our results can be mapped to the blind-spot scenario for bino-Higgsino DM in the MSSM, with other sfermions, the heavier Higgs boson, and the wino decoupled. |
0902.4568 | Debottam Das | Utpal Chattopadhyay, Debottam Das and D.P.Roy | Mixed Neutralino Dark Matter in Nonuniversal Gaugino Mass Models | 26 pages, 8 figures, 1 table. Minor changes in the text (section 2).
Version accepted for publication in Phys. Rev. D | Phys.Rev.D79:095013,2009 | 10.1103/PhysRevD.79.095013 | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have considered nonuniversal gaugino mass models of supergravity, arising
from a mixture of two superfield contributions to the gauge kinetic term,
belonging to a singlet and a nonsinglet representation of the GUT group. In
particular we analyse two models, where the contributing superfields belong to
the singlet and the 75-dimensional, and the singlet and the 200-dimensional
representations of SU(5). The resulting lightest superparticle is a mixed
bino-higgsino state in the first case and a mixed bino-wino-higgsino state in
the second. In both cases one obtains cosmologically compatible dark matter
relic density over broad regions of the parameter space. We predict promising
signals in direct dark matter detection experiments as well as in indirect
detection experiments via high energy neutrinos coming from their
pair-annihilation in the Sun. Besides, we find interesting $\gamma$-ray signal
rates that will be probed in the Fermi Gamma-ray Space Telescope. We also
expect promising collider signals at LHC in both cases.
| [
{
"created": "Thu, 26 Feb 2009 15:19:42 GMT",
"version": "v1"
},
{
"created": "Fri, 8 May 2009 06:51:16 GMT",
"version": "v2"
}
] | 2009-07-30 | [
[
"Chattopadhyay",
"Utpal",
""
],
[
"Das",
"Debottam",
""
],
[
"Roy",
"D. P.",
""
]
] | We have considered nonuniversal gaugino mass models of supergravity, arising from a mixture of two superfield contributions to the gauge kinetic term, belonging to a singlet and a nonsinglet representation of the GUT group. In particular we analyse two models, where the contributing superfields belong to the singlet and the 75-dimensional, and the singlet and the 200-dimensional representations of SU(5). The resulting lightest superparticle is a mixed bino-higgsino state in the first case and a mixed bino-wino-higgsino state in the second. In both cases one obtains cosmologically compatible dark matter relic density over broad regions of the parameter space. We predict promising signals in direct dark matter detection experiments as well as in indirect detection experiments via high energy neutrinos coming from their pair-annihilation in the Sun. Besides, we find interesting $\gamma$-ray signal rates that will be probed in the Fermi Gamma-ray Space Telescope. We also expect promising collider signals at LHC in both cases. |
hep-ph/9909370 | Marc Chemtob | Marc Chemtob and Gr\'egory Moreau | R-Parity Violating Contributions to Flavor Changing and CP Violation
Effects in Fermion and Sfermion Pair Production | Latex File. 4 pages. 1 postscript figure. Contribution to the
International Workshop on Linear Colliders, April 28-May 5, Sitges (SPAIN) | null | null | Saclay T99/099 | hep-ph | null | We examine the contributions from the R-parity odd interactions, $ \l_{ijk}
L_iL_jE_k^c $ and $ \l '_{ijk} L_i Q_j D^c_k$, to the total rates and the CP
asymmetry rates in the production of fermion-antifermion (lepton, down and up
quark) pairs and slepton-antislepton pairs of different flavors at leptonic
colliders. For the top-charm associated production case, we evaluate dynamical
distributions for the semileptonic top decay events and estimate the
sensitivity reach on the relevant parameters.
| [
{
"created": "Tue, 14 Sep 1999 17:12:54 GMT",
"version": "v1"
},
{
"created": "Wed, 15 Sep 1999 10:35:17 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Chemtob",
"Marc",
""
],
[
"Moreau",
"Grégory",
""
]
] | We examine the contributions from the R-parity odd interactions, $ \l_{ijk} L_iL_jE_k^c $ and $ \l '_{ijk} L_i Q_j D^c_k$, to the total rates and the CP asymmetry rates in the production of fermion-antifermion (lepton, down and up quark) pairs and slepton-antislepton pairs of different flavors at leptonic colliders. For the top-charm associated production case, we evaluate dynamical distributions for the semileptonic top decay events and estimate the sensitivity reach on the relevant parameters. |
hep-ph/0007118 | Alessandro Papa | Alessandro Papa | Check of the Bootstrap Conditions for the Gluon Reggeization | Talk given at the Crimean Summer School - Seminar, "New Trends in
High Energy Physics", Miskhor (Yalta), May 27 - June 4, 2000 (to be published
in the proceedings); 5 pages, uses axodraw.sty | null | null | UNICAL-TH 00/4 | hep-ph | null | The property of gluon Reggeization plays an essential role in the derivation
of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) equation for the cross sections at
high energy $\sqrt s$ in perturbative QCD. This property has been proved to all
orders of perturbation theory in the leading logarithmic approximation and it
is assumed to be valid also in the next-to-leading logarithmic approximation,
where it has been checked only to the first three orders of perturbation
theory. From $s$-channel unitarity, however, very stringent ``bootstrap''
conditions can be derived which, if fulfilled, leave no doubts that gluon
Reggeization holds.
| [
{
"created": "Wed, 12 Jul 2000 15:10:23 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Papa",
"Alessandro",
""
]
] | The property of gluon Reggeization plays an essential role in the derivation of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) equation for the cross sections at high energy $\sqrt s$ in perturbative QCD. This property has been proved to all orders of perturbation theory in the leading logarithmic approximation and it is assumed to be valid also in the next-to-leading logarithmic approximation, where it has been checked only to the first three orders of perturbation theory. From $s$-channel unitarity, however, very stringent ``bootstrap'' conditions can be derived which, if fulfilled, leave no doubts that gluon Reggeization holds. |
2406.02687 | Hector Tiblom | Admir Greljo, Anders Eller Thomsen, Hector Tiblom | Flavor Hierarchies From SU(2) Flavor and Quark-Lepton Unification | 23 pages, 4 figures, 2 tables, comments welcome | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | In our recent attempt to explain flavor hierarchies [1], a gauged SU(2)
flavor symmetry acting on left-handed fermions provides a ground to introduce
three independent rank-one contributions to the Yukawa matrices: a
renormalizable one for the third family, a mass-suppressed one for the second
family, and an additional loop-suppressed factor for the first family. Here, we
demonstrate how minimal quark-lepton unification \`a la Pati-Salam, relating
down-quarks to charged leptons, can significantly improve this mechanism. We
construct and thoroughly analyze a renormalizable model, performing a
comprehensive one-loop matching calculation that reveals how all flavor
hierarchies emerge from a single ratio of two scales. The first signatures may
appear in the upcoming charged lepton flavor violation experiments.
| [
{
"created": "Tue, 4 Jun 2024 18:00:45 GMT",
"version": "v1"
}
] | 2024-06-06 | [
[
"Greljo",
"Admir",
""
],
[
"Thomsen",
"Anders Eller",
""
],
[
"Tiblom",
"Hector",
""
]
] | In our recent attempt to explain flavor hierarchies [1], a gauged SU(2) flavor symmetry acting on left-handed fermions provides a ground to introduce three independent rank-one contributions to the Yukawa matrices: a renormalizable one for the third family, a mass-suppressed one for the second family, and an additional loop-suppressed factor for the first family. Here, we demonstrate how minimal quark-lepton unification \`a la Pati-Salam, relating down-quarks to charged leptons, can significantly improve this mechanism. We construct and thoroughly analyze a renormalizable model, performing a comprehensive one-loop matching calculation that reveals how all flavor hierarchies emerge from a single ratio of two scales. The first signatures may appear in the upcoming charged lepton flavor violation experiments. |
hep-ph/0007136 | Zhi-Zhong Xing | Zhi-zhong Xing | Final-state Rescattering Effects on B_d-->\pi\pi Decays and CP Violation | LaTex 9 pages (4 PS figures included). Typing errors removed. Latest
data considered. References added. Acknowledgements modified. Version to
appear in Phys. Lett. B | Phys.Lett. B493 (2000) 301-306 | 10.1016/S0370-2693(00)01150-3 | LMU-00-08 | hep-ph hep-ex | null | The significance of final-state interactions in B_d-->\pi\pi decays is
phenomenologically demonstrated by taking elastic \pi\pi--\pi\pi and inelastic
\pi\pi--D\bar{D} rescattering effects into consideration. We find that the
present experimental data on B^0_d-->\pi^+\pi^- can well be understood in this
approach without fine-tuning of the input parameters, and large CP-violating
asymmetries are expected to manifest themselves in such charmless rare
processes.
| [
{
"created": "Thu, 13 Jul 2000 13:41:42 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Oct 2000 08:17:35 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Xing",
"Zhi-zhong",
""
]
] | The significance of final-state interactions in B_d-->\pi\pi decays is phenomenologically demonstrated by taking elastic \pi\pi--\pi\pi and inelastic \pi\pi--D\bar{D} rescattering effects into consideration. We find that the present experimental data on B^0_d-->\pi^+\pi^- can well be understood in this approach without fine-tuning of the input parameters, and large CP-violating asymmetries are expected to manifest themselves in such charmless rare processes. |
1605.08681 | Alberto Salvio | Kristjan Kannike, Giulio Maria Pelaggi, Alberto Salvio, Alessandro
Strumia | The Higgs of the Higgs and the diphoton channel | 23 pages, 4 figures; one figure added and title and other wording
changed (version accepted by JHEP) | JHEP 1607 (2016) 101 | 10.1007/JHEP07(2016)101 | CERN-PH-TH-2016-128, IFUP-TH/2016 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | LHC results do not confirm conventional natural solutions to the Higgs mass
hierarchy problem, motivating alternative interpretations where a
hierarchically small weak scale is generated from a dimension-less quantum
dynamics. We propose weakly and strongly-coupled models where the field that
breaks classical scale invariance giving mass to itself and to the Higgs is
identified with a possible new resonance within the LHC reach. As an example,
we identify such resonance with the 750 GeV diphoton excess recently reported
by ATLAS and CMS. Such models can be extrapolated up to the Planck scale,
provide Dark Matter candidates and eliminate the SM vacuum instability.
| [
{
"created": "Fri, 27 May 2016 15:17:09 GMT",
"version": "v1"
},
{
"created": "Fri, 22 Jul 2016 07:46:05 GMT",
"version": "v2"
}
] | 2016-07-25 | [
[
"Kannike",
"Kristjan",
""
],
[
"Pelaggi",
"Giulio Maria",
""
],
[
"Salvio",
"Alberto",
""
],
[
"Strumia",
"Alessandro",
""
]
] | LHC results do not confirm conventional natural solutions to the Higgs mass hierarchy problem, motivating alternative interpretations where a hierarchically small weak scale is generated from a dimension-less quantum dynamics. We propose weakly and strongly-coupled models where the field that breaks classical scale invariance giving mass to itself and to the Higgs is identified with a possible new resonance within the LHC reach. As an example, we identify such resonance with the 750 GeV diphoton excess recently reported by ATLAS and CMS. Such models can be extrapolated up to the Planck scale, provide Dark Matter candidates and eliminate the SM vacuum instability. |
2006.16021 | Rafal Maciula | Rafal Maciula and Antoni Szczurek | Intrinsic charm in the nucleon and charm production at large rapidities
in collinear, hybrid and $k_T$-factorization approaches | 31 pages, 23 figures | null | 10.1007/JHEP10(2020)135 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the role of intrinsic charm (IC) in the nucleon for forward
production of $c$-quark (or $\bar c$-antiquark) in proton-proton collisions for
low and high energies. The calculations are performed in
collinear-factorization approach with on-shell partons, $k_T$-factorization
approach with off-shell partons as well as in a hybrid approach using collinear
charm distributions and unintegrated (transverse momentum dependent) gluon
distributions. For the collinear-factorization approach we use matrix elements
for both massless and massive charm quarks/antiquarks. The distributions in
rapidity and transverse momentum of charm quark/antiquark are shown for a few
different models of IC. Forward charm production is dominated by $gc$-fusion
processes. The IC contribution dominates over the standard pQCD (extrinsic)
$gg$-fusion mechanism of $c\bar c$-pair production at large rapidities or
Feynman-$x_F$. We perform similar calculations within leading-order and
next-to-leading order $k_T$-factorization approach. The $k_T$-factorization
approach leads to much larger cross sections than the LO collinear approach. At
high energies and large rapidities of $c$-quark or $\bar c$-antiquark one tests
gluon distributions at extremely small $x$. The IC contribution has important
consequences for high-energy neutrino production in the Ice-Cube experiment and
can be, to some extent, tested at the LHC by the SHIP and FASER experiments by
studies of the $\nu_{\tau}$ neutrino production.
| [
{
"created": "Mon, 29 Jun 2020 13:06:12 GMT",
"version": "v1"
}
] | 2020-12-02 | [
[
"Maciula",
"Rafal",
""
],
[
"Szczurek",
"Antoni",
""
]
] | We discuss the role of intrinsic charm (IC) in the nucleon for forward production of $c$-quark (or $\bar c$-antiquark) in proton-proton collisions for low and high energies. The calculations are performed in collinear-factorization approach with on-shell partons, $k_T$-factorization approach with off-shell partons as well as in a hybrid approach using collinear charm distributions and unintegrated (transverse momentum dependent) gluon distributions. For the collinear-factorization approach we use matrix elements for both massless and massive charm quarks/antiquarks. The distributions in rapidity and transverse momentum of charm quark/antiquark are shown for a few different models of IC. Forward charm production is dominated by $gc$-fusion processes. The IC contribution dominates over the standard pQCD (extrinsic) $gg$-fusion mechanism of $c\bar c$-pair production at large rapidities or Feynman-$x_F$. We perform similar calculations within leading-order and next-to-leading order $k_T$-factorization approach. The $k_T$-factorization approach leads to much larger cross sections than the LO collinear approach. At high energies and large rapidities of $c$-quark or $\bar c$-antiquark one tests gluon distributions at extremely small $x$. The IC contribution has important consequences for high-energy neutrino production in the Ice-Cube experiment and can be, to some extent, tested at the LHC by the SHIP and FASER experiments by studies of the $\nu_{\tau}$ neutrino production. |
1512.05564 | Shinya Matsuzaki | Shinya Matsuzaki and Koichi Yamawaki | 750 GeV Diphoton Signal from One-Family Walking Technipion | 4 pages; version to appear in MPLA | null | 10.1142/S0217732316300160 | null | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The ATLAS and CMS groups have recently reported an excess at around 750 GeV
with the local significance by about 3 sigma in the diphoton channel at the 13
TeV LHC. We give a possible explanation for the excess by a composite pseudo
scalar $(P^0)$ predicted in the one-family model of walking technicolor.
| [
{
"created": "Thu, 17 Dec 2015 12:47:42 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Apr 2016 08:08:10 GMT",
"version": "v2"
}
] | 2016-06-22 | [
[
"Matsuzaki",
"Shinya",
""
],
[
"Yamawaki",
"Koichi",
""
]
] | The ATLAS and CMS groups have recently reported an excess at around 750 GeV with the local significance by about 3 sigma in the diphoton channel at the 13 TeV LHC. We give a possible explanation for the excess by a composite pseudo scalar $(P^0)$ predicted in the one-family model of walking technicolor. |
2108.06203 | Guy D. Moore | Aidan Chaumet, Guy D. Moore | Misalignment vs Topology in Axion-Like Models | 16 pages, 3 figures | null | null | null | hep-ph | http://creativecommons.org/licenses/by-sa/4.0/ | Cosmological axions, an important dark matter candidate, are generated when a
scalar field with a spontaneously broken O(2) invariance develops an explicitly
O(2)-breaking tilt cosmologically, leading to coherent production of
long-wavelength modes which could be dark matter. It appears that the
production efficiency of this mechanism is low, despite possible production
from topological structures. To understand this better, we examine production
in O(N) generalizations. In particular we highlight the importance of how fast
the explicit O(N)-breaking potential turns on.
| [
{
"created": "Fri, 13 Aug 2021 12:46:15 GMT",
"version": "v1"
}
] | 2021-08-16 | [
[
"Chaumet",
"Aidan",
""
],
[
"Moore",
"Guy D.",
""
]
] | Cosmological axions, an important dark matter candidate, are generated when a scalar field with a spontaneously broken O(2) invariance develops an explicitly O(2)-breaking tilt cosmologically, leading to coherent production of long-wavelength modes which could be dark matter. It appears that the production efficiency of this mechanism is low, despite possible production from topological structures. To understand this better, we examine production in O(N) generalizations. In particular we highlight the importance of how fast the explicit O(N)-breaking potential turns on. |
hep-ph/9507330 | null | Y. Srivastava, A. Widom and E. Sassaroli | Real and Virtual Strange Processes | 11 pages, LaTex file, one uuencoded file for the 3 figures. The
postcript file for the figures is also available on request. Talk presented
by Y. Srivastava at the ``Workshop on Physics and Detectors for DAFNE",
Frascati, April 1995 | null | null | null | hep-ph | null | Following notions of quantum mechanics as interpreted by the Copenhagen
School, we make a distinction between measurements involving one or two virtual
K mesons. New predictions result for the period of K oscillations at the Phi
Factory.
| [
{
"created": "Tue, 18 Jul 1995 14:56:09 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Srivastava",
"Y.",
""
],
[
"Widom",
"A.",
""
],
[
"Sassaroli",
"E.",
""
]
] | Following notions of quantum mechanics as interpreted by the Copenhagen School, we make a distinction between measurements involving one or two virtual K mesons. New predictions result for the period of K oscillations at the Phi Factory. |
hep-ph/9702239 | Tommaso Calarco | V. Barone (Universita` di Torino - INFN, Italy), T. Calarco
(Universita` di Ferrara - INFN, Italy), A. Drago (Universita` di Ferrara -
INFN, Italy) | Double-Spin Transverse Asymmetries in Drell-Yan Processes | 8 pages, REVTeX, 6 figures included as file figures.tar.gz | Phys.Rev. D56 (1997) 527-530 | 10.1103/PhysRevD.56.527 | null | hep-ph | null | We calculate the double-spin transverse asymmetries for the Drell-Yan lepton
pair production in p-p and p-anti p collisions. We assume the transverse and
the longitudinal polarization densities to be equal at a very small scale, as
it is suggested by confinement model results. Using a global fit for the
longitudinal distributions, we find transverse asymmetries of order of 10^-2 at
most, in the accessible kinematic regions.
| [
{
"created": "Tue, 4 Feb 1997 08:04:51 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Barone",
"V.",
"",
"Universita` di Torino - INFN, Italy"
],
[
"Calarco",
"T.",
"",
"Universita` di Ferrara - INFN, Italy"
],
[
"Drago",
"A.",
"",
"Universita` di Ferrara -\n INFN, Italy"
]
] | We calculate the double-spin transverse asymmetries for the Drell-Yan lepton pair production in p-p and p-anti p collisions. We assume the transverse and the longitudinal polarization densities to be equal at a very small scale, as it is suggested by confinement model results. Using a global fit for the longitudinal distributions, we find transverse asymmetries of order of 10^-2 at most, in the accessible kinematic regions. |
2310.05474 | Federica Pompa | Federica Pompa, Olga Mena | How much do neutrinos live and weigh? | 10 pages, 9 figures | null | null | null | hep-ph astro-ph.HE hep-ex | http://creativecommons.org/licenses/by/4.0/ | The next-generation water Cherenkov Hyper-Kamiokande detector will be able to
detect thousands of neutrino events from a galactic Supernova explosion via
Inverse Beta Decay processes followed by neutron capture on Gadolinium. This
superb statistics provides a unique window to set bounds on neutrino
properties, as its mass and lifetime. We shall explore the capabilities of such
a future detector, constraining the former two properties via the time delay
and the flux suppression induced in the Supernovae neutrino time and energy
spectra. Special attention will be devoted to the statistically sub-dominant
elastic scattering induced events, normally neglected, which can substantially
improve the neutrino mass bound via time delays. When allowing for a invisible
decaying scenario, the $95\%~$C.L. lower bound on $\tau/m$ is almost one order
of magnitude better than the one found with SN1987A neutrino events.
Simultaneous limits can be set on both $m_\nu$ and $\tau_{\nu}$, combining the
neutrino flux suppression with the time-delay signature: the best constrained
lifetime is that of $\nu_1$, which has the richest electronic component. We
find $\tau_{\nu_1}\gtrsim 4\times 10^5~$s at $95\%~$C.L. The tightest
$95\%~$C.L. bound on the neutrino mass we find is $0.34~$eV, which is not only
competitive with the tightest neutrino mass limits nowadays, but also
comparable to future laboratory direct mass searches. Both mass and lifetime
limits are independent on the mass ordering, which makes our results very
robust and relevant.
| [
{
"created": "Mon, 9 Oct 2023 07:33:46 GMT",
"version": "v1"
}
] | 2023-10-10 | [
[
"Pompa",
"Federica",
""
],
[
"Mena",
"Olga",
""
]
] | The next-generation water Cherenkov Hyper-Kamiokande detector will be able to detect thousands of neutrino events from a galactic Supernova explosion via Inverse Beta Decay processes followed by neutron capture on Gadolinium. This superb statistics provides a unique window to set bounds on neutrino properties, as its mass and lifetime. We shall explore the capabilities of such a future detector, constraining the former two properties via the time delay and the flux suppression induced in the Supernovae neutrino time and energy spectra. Special attention will be devoted to the statistically sub-dominant elastic scattering induced events, normally neglected, which can substantially improve the neutrino mass bound via time delays. When allowing for a invisible decaying scenario, the $95\%~$C.L. lower bound on $\tau/m$ is almost one order of magnitude better than the one found with SN1987A neutrino events. Simultaneous limits can be set on both $m_\nu$ and $\tau_{\nu}$, combining the neutrino flux suppression with the time-delay signature: the best constrained lifetime is that of $\nu_1$, which has the richest electronic component. We find $\tau_{\nu_1}\gtrsim 4\times 10^5~$s at $95\%~$C.L. The tightest $95\%~$C.L. bound on the neutrino mass we find is $0.34~$eV, which is not only competitive with the tightest neutrino mass limits nowadays, but also comparable to future laboratory direct mass searches. Both mass and lifetime limits are independent on the mass ordering, which makes our results very robust and relevant. |
2003.09400 | Matteo Rinaldi | Matteo Rinaldi | Double parton correlations in mesons within AdS/QCD soft-wall models: a
first comparison with lattice data | 27 pages, 18 figures. Accepted version in EPJC | null | 10.1140/epjc/s10052-020-8241-y | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Double parton distribution functions (dPDFs), entering the double parton
scattering (DPS) cross section, are unknown fundamental quantities encoding new
interesting properties of hadrons. Here, the pion dPDFs are investigated within
different holographic QCD quark models in order to access their basic features.
Results of the calculation,s obtained within the AdS/QCD soft-wall approach,
have been compared with predictions of lattice QCD evaluations of the pion
two-current correlation functions. The present analysis confirms that double
parton correlations, affecting dPDFs, are very important and not direct
accessible from generalised parton distribution functions and electromagnetic
form factors. The comparison between lattice data and quark model calculations
unveils the relevance of the contributions of high partonic Fock states in the
pion. Nevertheless, by using a complete general procedure, results of lattice
QCD have been used, for the first time, to estimate the mean value of the so
called $\sigma_{eff}$, a relevant experimental observable for DPS processes. In
addition, the results of the first calculations of the $\rho$ meson dPDFs are
discussed in order to make predictions.
| [
{
"created": "Fri, 20 Mar 2020 17:28:32 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Jul 2020 07:33:24 GMT",
"version": "v2"
}
] | 2020-08-26 | [
[
"Rinaldi",
"Matteo",
""
]
] | Double parton distribution functions (dPDFs), entering the double parton scattering (DPS) cross section, are unknown fundamental quantities encoding new interesting properties of hadrons. Here, the pion dPDFs are investigated within different holographic QCD quark models in order to access their basic features. Results of the calculation,s obtained within the AdS/QCD soft-wall approach, have been compared with predictions of lattice QCD evaluations of the pion two-current correlation functions. The present analysis confirms that double parton correlations, affecting dPDFs, are very important and not direct accessible from generalised parton distribution functions and electromagnetic form factors. The comparison between lattice data and quark model calculations unveils the relevance of the contributions of high partonic Fock states in the pion. Nevertheless, by using a complete general procedure, results of lattice QCD have been used, for the first time, to estimate the mean value of the so called $\sigma_{eff}$, a relevant experimental observable for DPS processes. In addition, the results of the first calculations of the $\rho$ meson dPDFs are discussed in order to make predictions. |
hep-ph/9904374 | Dmitri Khokhlov | D.L. Khokhlov | On the decay of neutral kaons | 2 pages LaTeX | null | null | null | hep-ph | null | It is shown that the data on the decay of neutral kaons may be explained
without CP-violation.
| [
{
"created": "Sat, 17 Apr 1999 15:14:24 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Khokhlov",
"D. L.",
""
]
] | It is shown that the data on the decay of neutral kaons may be explained without CP-violation. |
hep-ph/9711377 | G. Valencia | G. Valencia | Long Distance Contribution to $K_L \to \ell^+ \ell^-$ | References added, one typo corrected. Version to appear in Nuclear
Physics B | Nucl.Phys. B517 (1998) 339-352 | 10.1016/S0550-3213(98)00116-3 | ISU-HET-97-6 | hep-ph hep-ex | null | We revisit the calculation of the long distance contribution to $K_L \to
\mu^+ \mu^-$. We discuss this process within the framework of chiral
perturbation theory, and also using simple models for the $K_L \gamma^*
\gamma^*$ vertex. We argue that it is unlikely that this mode can be used to
extract information on short distance parameters. The process $K_L \to e^+ e^-$
is also long-distance dominated and we find that $B(K_L \to e^+ e^-) \approx 9
\times 10^{-12}$.
| [
{
"created": "Tue, 18 Nov 1997 21:39:24 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Feb 1998 17:40:28 GMT",
"version": "v2"
}
] | 2009-10-30 | [
[
"Valencia",
"G.",
""
]
] | We revisit the calculation of the long distance contribution to $K_L \to \mu^+ \mu^-$. We discuss this process within the framework of chiral perturbation theory, and also using simple models for the $K_L \gamma^* \gamma^*$ vertex. We argue that it is unlikely that this mode can be used to extract information on short distance parameters. The process $K_L \to e^+ e^-$ is also long-distance dominated and we find that $B(K_L \to e^+ e^-) \approx 9 \times 10^{-12}$. |
hep-ph/9501213 | Herbert Weigel | R. Alkofer, H. Reinhardt and H. Weigel | Baryons as Chiral Solitons in the Nambu--Jona-Lasinio Model | 120 pages, uuencoded and compressed postscript file is submitted,
hardcopy available upon request. | Phys.Rept.265:139-252,1996 | 10.1016/0370-1573(95)00018-6 | UNITU-THEP-25/1994 | hep-ph | null | The description of baryons as chiral solitons of the Nambu--Jona--Lasinio
(NJL) model is reviewed. A motivation for the soliton description of baryons is
provided from large $N_C$ QCD. Rigorous results on the spontaneous breaking of
chiral symmetry in QCD are discussed. It is then argued that the NJL model
provides a fair description of low--energy hadron physics. The NJL model is
therefore employed to mimic the low--energy chiral flavor dynamics of QCD. The
model is bosonized by functional integral techniques and the physical content
of the emerging effective meson theory is discussed. In particular, its
relation to the Skyrme model is established. The static soliton solutions of
the bosonized NJL model are found, their properties discussed, and the
influence of various meson fields studied. These considerations provide strong
support of Witten's conjecture that baryons can be understood as soliton
solutions of effective meson theories. The chiral soliton of the NJL model is
then quantized in a semiclassical fashion and various static properties of the
nucleon are studied. The dominating $1/N_C$ corrections to the semiclassically
quantized soliton are investigated. Time--dependent meson fluctuations off the
chiral soliton are explored and employed to estimate the quantum corrections to
the soliton mass. Finally, hyperons are described as chiral solitons of the NJL
model. This is done in both, the collective rotational approach of Yabu and
Ando as well as in the bound state approach of Callan and Klebanov.
| [
{
"created": "Thu, 5 Jan 1995 09:01:33 GMT",
"version": "v1"
}
] | 2016-09-01 | [
[
"Alkofer",
"R.",
""
],
[
"Reinhardt",
"H.",
""
],
[
"Weigel",
"H.",
""
]
] | The description of baryons as chiral solitons of the Nambu--Jona--Lasinio (NJL) model is reviewed. A motivation for the soliton description of baryons is provided from large $N_C$ QCD. Rigorous results on the spontaneous breaking of chiral symmetry in QCD are discussed. It is then argued that the NJL model provides a fair description of low--energy hadron physics. The NJL model is therefore employed to mimic the low--energy chiral flavor dynamics of QCD. The model is bosonized by functional integral techniques and the physical content of the emerging effective meson theory is discussed. In particular, its relation to the Skyrme model is established. The static soliton solutions of the bosonized NJL model are found, their properties discussed, and the influence of various meson fields studied. These considerations provide strong support of Witten's conjecture that baryons can be understood as soliton solutions of effective meson theories. The chiral soliton of the NJL model is then quantized in a semiclassical fashion and various static properties of the nucleon are studied. The dominating $1/N_C$ corrections to the semiclassically quantized soliton are investigated. Time--dependent meson fluctuations off the chiral soliton are explored and employed to estimate the quantum corrections to the soliton mass. Finally, hyperons are described as chiral solitons of the NJL model. This is done in both, the collective rotational approach of Yabu and Ando as well as in the bound state approach of Callan and Klebanov. |
hep-ph/9801366 | null | D. Pocanic (Univ. of Virginia) | Low Energy Experiments on pi-pi Scattering | Talk given by D. Pocanic at Workshop on Chiral Dynamics: Theory and
Experiment (ChPT 97), Mainz, Germany, 1-5 Sep 1997; 16 pages, 7 PostScript
figures, writen in LaTeX, uses packages "lamuphys" and "epsfig". Author's
e-mail: pocanic@virginia.edu | null | 10.1007/BFb0104915 | UVA-INPP-98-01 [19 Jan 1998] | hep-ph | null | General interest in a precise determination of the threshold pi-pi amplitudes
has recently increased markedly due to a controversy regarding the size of
<0|qbar q|0>, the scalar quark condensate. This paper examines the current
experimental information on the pi-pi scattering lengths, in particular the
recent low energy pi N -> pi pi N data from several laboratories and the
related application of the Chew-Low-Goebel technique well below 1 GeV/c
momentum. It appears that uncertainties related to the treatment of
non-pion-exchange backgrounds in these studies do not yet allow an unambiguous
resolution of the <0|qbar q|0> size. However, near-term prospects for new
model-independent results of improved precision are very good.
| [
{
"created": "Wed, 21 Jan 1998 00:56:52 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Pocanic",
"D.",
"",
"Univ. of Virginia"
]
] | General interest in a precise determination of the threshold pi-pi amplitudes has recently increased markedly due to a controversy regarding the size of <0|qbar q|0>, the scalar quark condensate. This paper examines the current experimental information on the pi-pi scattering lengths, in particular the recent low energy pi N -> pi pi N data from several laboratories and the related application of the Chew-Low-Goebel technique well below 1 GeV/c momentum. It appears that uncertainties related to the treatment of non-pion-exchange backgrounds in these studies do not yet allow an unambiguous resolution of the <0|qbar q|0> size. However, near-term prospects for new model-independent results of improved precision are very good. |
2212.11900 | Xiaoran Zhao | Roberto Franceschini and Xiaoran Zhao | Going all the way in the search for WIMP dark matter at the muon
collider through precision measurements | 11 pages, 9 figures | null | 10.1140/epjc/s10052-023-11724-3 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Dark Matter is a necessary ingredient for a complete theory of Nature, which
has so far remained elusive in laboratory searches for new particles. Searches
at current and future colliders are in principle a promising way to search for
electroweak charged dark matter particles, but the sensitivity of experiments
at the LHC and future $pp$ colliders falls short to fully probe the whole mass
range allowed for electroweak charged dark matter particles, which extends in
principle up to the O(0.1) PeV. In this work we examine the effect of on-shell
and off-shell propagation of electroweak charged thermal dark matter particles
on integrated and differential rates of several Standard Model final states at
the muon collider, considering candidates from weak 2-plet at the TeV scale up
to 7-plet and 9-plet in the O(0.1) PeV ballpark. For fermionic WIMPs we find
that all dark matter candidates with $n\leq 5$, corresponding to a thermal mass
up to 14~TeV, can be excluded at the high-energy muon collider for some
center-of-mass energy at or below 14~TeV. For the $n>5$ WIMPs our results show
that higher energy muon colliders offer a route to conclusively probe both
scalar and fermionic WIMPs off-shell production all the way up to the
perturbativity bound for WIMP dark matter at O(0.1)~PeV. Our results bring
WIMPs over the whole allowed mass range in the realm of collider searches and
motivate research and development for the realization of a high energy muon
collider.
| [
{
"created": "Thu, 22 Dec 2022 17:39:22 GMT",
"version": "v1"
}
] | 2023-07-26 | [
[
"Franceschini",
"Roberto",
""
],
[
"Zhao",
"Xiaoran",
""
]
] | Dark Matter is a necessary ingredient for a complete theory of Nature, which has so far remained elusive in laboratory searches for new particles. Searches at current and future colliders are in principle a promising way to search for electroweak charged dark matter particles, but the sensitivity of experiments at the LHC and future $pp$ colliders falls short to fully probe the whole mass range allowed for electroweak charged dark matter particles, which extends in principle up to the O(0.1) PeV. In this work we examine the effect of on-shell and off-shell propagation of electroweak charged thermal dark matter particles on integrated and differential rates of several Standard Model final states at the muon collider, considering candidates from weak 2-plet at the TeV scale up to 7-plet and 9-plet in the O(0.1) PeV ballpark. For fermionic WIMPs we find that all dark matter candidates with $n\leq 5$, corresponding to a thermal mass up to 14~TeV, can be excluded at the high-energy muon collider for some center-of-mass energy at or below 14~TeV. For the $n>5$ WIMPs our results show that higher energy muon colliders offer a route to conclusively probe both scalar and fermionic WIMPs off-shell production all the way up to the perturbativity bound for WIMP dark matter at O(0.1)~PeV. Our results bring WIMPs over the whole allowed mass range in the realm of collider searches and motivate research and development for the realization of a high energy muon collider. |
1102.5610 | Seung-il Nam | Seung-il Nam | An effective thermodynamic potential from the instanton vacuum with the
Polyakov loop | 10 pages, 5 figures, Talk given at the international workshop Hadron
Nuclear Physics (HNP) 2011, 21~24 Feb 2011, Pohang, Korea | null | 10.1051/epjconf/20122003002 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this talk, we report our recent studies on an effective thermodynamic
potential (Omega_eff) at finite temperature (T>0) and zero quark-chemical
potential (mu_R=0), using the singular-gauge instanton solution and Matsubara
formula for N_c=3 and N_f=2 in the chiral limit, i.e. m_q=0. The
momentum-dependent constituent-quark mass is computed as a function of T,
together with the Harrington-Shepard caloron solution in the large-N_c limit.
In addition, we take into account the imaginary quark-chemical potential mu_I =
A_4, indentified as the traced Polayakov-loop (Phi) as an order parameter for
the Z(N_c) symmetry, characterizing the confinement (intact) and deconfinement
(spontaneously broken) phases. As a consequence, we observe the crossover of
the chiral (chi) order parameter sigma^2 and Phi. It also turns out that the
critical temperature for the deconfinement phase transition, T^Z_c is lowered
by about (5~10) % in comparison to the case with the constant constituent-quark
mass. This behavior can be understood by considerable effects from the partial
chiral restoration and nontrivial QCD vacuum on the Phi. Numerical results show
that the crossover transitions occur at (T^chi_c,T^Z_c) ~ (216,227) MeV.
| [
{
"created": "Mon, 28 Feb 2011 07:13:50 GMT",
"version": "v1"
}
] | 2015-05-27 | [
[
"Nam",
"Seung-il",
""
]
] | In this talk, we report our recent studies on an effective thermodynamic potential (Omega_eff) at finite temperature (T>0) and zero quark-chemical potential (mu_R=0), using the singular-gauge instanton solution and Matsubara formula for N_c=3 and N_f=2 in the chiral limit, i.e. m_q=0. The momentum-dependent constituent-quark mass is computed as a function of T, together with the Harrington-Shepard caloron solution in the large-N_c limit. In addition, we take into account the imaginary quark-chemical potential mu_I = A_4, indentified as the traced Polayakov-loop (Phi) as an order parameter for the Z(N_c) symmetry, characterizing the confinement (intact) and deconfinement (spontaneously broken) phases. As a consequence, we observe the crossover of the chiral (chi) order parameter sigma^2 and Phi. It also turns out that the critical temperature for the deconfinement phase transition, T^Z_c is lowered by about (5~10) % in comparison to the case with the constant constituent-quark mass. This behavior can be understood by considerable effects from the partial chiral restoration and nontrivial QCD vacuum on the Phi. Numerical results show that the crossover transitions occur at (T^chi_c,T^Z_c) ~ (216,227) MeV. |
0712.3926 | Fedor Simkovic | Fedor Simkovic, Rastislav Dvornicky, Amand Faessler | Exact relativistic tritium beta-decay endpoint spectrum in a hadron
model | 6 pages, 1 figure | Phys.Rev.C77:055502,2008 | 10.1103/PhysRevC.77.055502 | null | hep-ph | null | We present the relativistic calculation of the beta-decay of tritium in a
hadron model. The elementary particle treatment of the transition 3H -> 3He +
e^- + nu_e is performed in analogy with the description of the beta-decay of
neutron. The effects of higher order terms of hadron current and nuclear recoil
are taken into account in this formalism. The relativistic Kurie function is
derived and presented in a simple form suitable for the determination of
neutrino masses from the shape of the endpoint spectrum. A connection with the
commonly used Kurie function is established.
| [
{
"created": "Sun, 23 Dec 2007 15:25:53 GMT",
"version": "v1"
},
{
"created": "Mon, 5 May 2008 15:44:38 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Simkovic",
"Fedor",
""
],
[
"Dvornicky",
"Rastislav",
""
],
[
"Faessler",
"Amand",
""
]
] | We present the relativistic calculation of the beta-decay of tritium in a hadron model. The elementary particle treatment of the transition 3H -> 3He + e^- + nu_e is performed in analogy with the description of the beta-decay of neutron. The effects of higher order terms of hadron current and nuclear recoil are taken into account in this formalism. The relativistic Kurie function is derived and presented in a simple form suitable for the determination of neutrino masses from the shape of the endpoint spectrum. A connection with the commonly used Kurie function is established. |
1110.3594 | Traini Marco | Marco Traini | Charge symmetry violation: a NNLO study of partonic observables | revtex4, 7 pages, 3 figures; text improved, new comments and
references | Phys.Lett.B707:523-528,2012 | 10.1016/j.physletb.2012.01.003 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Charge and isospin symmetry violations to valence and sea distribution
functions in the nucleon are evaluated (at low resolution scale) by means of a
meson cloud model and light-cone quark wave functions. Their perturbative
evolution are implemented at Next-to-next-to-leading order (NNLO) using an
original evolution code in order to include the perturbatively generated
strange - anti-strange asymmetry typical of the three loop evolution expansion.
Charge symmetry violating QED effects are also added and the distributions,
evolved at the experimental scale, are compared with available information. The
role of non-perturbative effects is emphasized in the interpretation of the, so
called, NuTeV anomaly and new experiments at very-high energy.
| [
{
"created": "Mon, 17 Oct 2011 08:04:36 GMT",
"version": "v1"
},
{
"created": "Wed, 7 Dec 2011 11:14:30 GMT",
"version": "v2"
}
] | 2015-05-30 | [
[
"Traini",
"Marco",
""
]
] | Charge and isospin symmetry violations to valence and sea distribution functions in the nucleon are evaluated (at low resolution scale) by means of a meson cloud model and light-cone quark wave functions. Their perturbative evolution are implemented at Next-to-next-to-leading order (NNLO) using an original evolution code in order to include the perturbatively generated strange - anti-strange asymmetry typical of the three loop evolution expansion. Charge symmetry violating QED effects are also added and the distributions, evolved at the experimental scale, are compared with available information. The role of non-perturbative effects is emphasized in the interpretation of the, so called, NuTeV anomaly and new experiments at very-high energy. |
1105.2388 | Chia-Min Lin | Lu-Yun Lee and Chia-Min Lin | Non-Gaussianity from two right-handed sneutrino curvaton decays | 9 pages, 6 figures, 1 table, to appear in General Relativity and
Gravitation | null | 10.1007/s10714-012-1403-y | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we consider the effect of two right-handed sneutrino curvaton
decays and investigate the parameter space. We compare the difference of the
result between single- and two-curvaton cases. We find one Yukawa coupling of
the right-handed snetrinos can be as large as $\lambda \sim 0.1$ while the
other one is much smaller which is consistent with the idea that only one
generation of the neutrino mass may be much smaller than others. When the
curvatons decay, we assume both of them subdominate the energy density of the
universe. We find that, unlike a single curvaton case, here a small or
negative, as well as a large $f_{NL}$ can be generated.
| [
{
"created": "Thu, 12 May 2011 07:25:31 GMT",
"version": "v1"
},
{
"created": "Tue, 12 Jul 2011 07:51:55 GMT",
"version": "v2"
},
{
"created": "Fri, 22 Jun 2012 06:54:51 GMT",
"version": "v3"
}
] | 2012-06-25 | [
[
"Lee",
"Lu-Yun",
""
],
[
"Lin",
"Chia-Min",
""
]
] | In this paper, we consider the effect of two right-handed sneutrino curvaton decays and investigate the parameter space. We compare the difference of the result between single- and two-curvaton cases. We find one Yukawa coupling of the right-handed snetrinos can be as large as $\lambda \sim 0.1$ while the other one is much smaller which is consistent with the idea that only one generation of the neutrino mass may be much smaller than others. When the curvatons decay, we assume both of them subdominate the energy density of the universe. We find that, unlike a single curvaton case, here a small or negative, as well as a large $f_{NL}$ can be generated. |
hep-ph/0310223 | Spencer Klein | Spencer Klein and Joakim Nystrand | Photoproduction of $J/\psi$ and $\Upsilon$ in pp and $\bar{p}p$
Collisions | Typos in references fixed Presented at "Small-x and Diffraction 2003,
Sept. 17-20, 2003, Fermilab. 5 pages with 2 figures | null | null | null | hep-ph | null | Exclusive vector meson photoproduction, $pp\to ppV$ and $\bar pp\to\bar ppV$
occurs with significant rates at hadron colliders. The reaction can be used to
study the gluon distribution of protons. Vector mesons may be produced with
either proton as a target; because of interference between the two production
channels, the $p_T$ spectra of vector mesons produced in $pp$ and $\bar pp$
collisions are quite different. Because of the unique event signature, vector
meson photoproduction can be separated from hadroproduction events, despite the
small ratio of cross sections. We consider production of $J/\psi$ and
$\Upsilon$ at RHIC, the Tevatron and the LHC.
| [
{
"created": "Sat, 18 Oct 2003 06:05:30 GMT",
"version": "v1"
},
{
"created": "Wed, 22 Oct 2003 22:56:12 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Klein",
"Spencer",
""
],
[
"Nystrand",
"Joakim",
""
]
] | Exclusive vector meson photoproduction, $pp\to ppV$ and $\bar pp\to\bar ppV$ occurs with significant rates at hadron colliders. The reaction can be used to study the gluon distribution of protons. Vector mesons may be produced with either proton as a target; because of interference between the two production channels, the $p_T$ spectra of vector mesons produced in $pp$ and $\bar pp$ collisions are quite different. Because of the unique event signature, vector meson photoproduction can be separated from hadroproduction events, despite the small ratio of cross sections. We consider production of $J/\psi$ and $\Upsilon$ at RHIC, the Tevatron and the LHC. |
2202.07975 | Katharina Vo{\ss} | Simone Alioli, Juan Fuster, Maria Vittoria Garzelli, Alessandro
Gavardi, Adrian Irles, Davide Melini, Sven-Olaf Moch, Peter Uwer, Katharina
Vo{\ss} | Phenomenology of $t\bar{t}j + X$ production at the LHC | 64 pages, LaTeX, 38 figures, 14 tables, slightly modified version, as
in JHEP | JHEP 05 (2022) 146 | 10.1007/JHEP05(2022)146 | DESY-22-030, HU-EP-22/05, IFIC/22-05 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present phenomenological results for $t\bar{t}j + X$ production at the
Large Hadron Collider, of interest for designing forthcoming experimental
analyses of this process. We focus on those cases where the $t\bar{t}j + X$
process is considered as a signal. We discuss present theoretical uncertainties
and the dependence on relevant input parameters entering the computation. For
the ${\cal R}$ distribution, which depends on the invariant mass of the
$t\bar{t}j$-system, we present reference predictions in the on-shell,
$\overline{\mbox{MS}}$ and MSR top-quark mass renormalization schemes, applying
the latter scheme to this process for the first time. Our conclusions are
particularly interesting for those analyses aiming at extracting the top-quark
mass from cross-section measurements.
| [
{
"created": "Wed, 16 Feb 2022 10:32:45 GMT",
"version": "v1"
},
{
"created": "Fri, 10 Jun 2022 12:35:28 GMT",
"version": "v2"
}
] | 2022-06-13 | [
[
"Alioli",
"Simone",
""
],
[
"Fuster",
"Juan",
""
],
[
"Garzelli",
"Maria Vittoria",
""
],
[
"Gavardi",
"Alessandro",
""
],
[
"Irles",
"Adrian",
""
],
[
"Melini",
"Davide",
""
],
[
"Moch",
"Sven-Olaf",
""
... | We present phenomenological results for $t\bar{t}j + X$ production at the Large Hadron Collider, of interest for designing forthcoming experimental analyses of this process. We focus on those cases where the $t\bar{t}j + X$ process is considered as a signal. We discuss present theoretical uncertainties and the dependence on relevant input parameters entering the computation. For the ${\cal R}$ distribution, which depends on the invariant mass of the $t\bar{t}j$-system, we present reference predictions in the on-shell, $\overline{\mbox{MS}}$ and MSR top-quark mass renormalization schemes, applying the latter scheme to this process for the first time. Our conclusions are particularly interesting for those analyses aiming at extracting the top-quark mass from cross-section measurements. |
1606.04517 | Yongchao Zhang | P. S. Bhupal Dev, D. Kazanas, R. N. Mohapatra, V. L. Teplitz, Yongchao
Zhang | Heavy right-handed neutrino dark matter and PeV neutrinos at IceCube | 21 pages, 5 figures, minor corrections, version for publication in
JCAP | JCAP 1608, 034 (2016) | 10.1088/1475-7516/2016/08/034 | ULB-TH/16-10 | hep-ph astro-ph.CO astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss a simple non-supersymmetric model based on the electroweak gauge
group $SU(2)_L\times SU(2)^\prime\times U(1)_{B-L}$ where the lightest of the
right-handed neutrinos, which are part of the leptonic doublet of
$SU(2)^\prime$, play the role of a long-lived unstable dark matter with mass in
the multi-PeV range. We use a resonant $s$-channel annihilation to obtain the
correct thermal relic density and relax the unitarity bound on dark matter
mass. In this model, there exists a 3-body dark matter decay mode producing tau
leptons and neutrinos, which could be the source for the PeV cascade events
observed in the IceCube experiment. The model can be tested with more precise
flavor information of the highest-energy neutrino events in future data.
| [
{
"created": "Tue, 14 Jun 2016 19:30:49 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Jun 2016 11:53:55 GMT",
"version": "v2"
},
{
"created": "Wed, 10 Aug 2016 03:06:57 GMT",
"version": "v3"
}
] | 2016-08-22 | [
[
"Dev",
"P. S. Bhupal",
""
],
[
"Kazanas",
"D.",
""
],
[
"Mohapatra",
"R. N.",
""
],
[
"Teplitz",
"V. L.",
""
],
[
"Zhang",
"Yongchao",
""
]
] | We discuss a simple non-supersymmetric model based on the electroweak gauge group $SU(2)_L\times SU(2)^\prime\times U(1)_{B-L}$ where the lightest of the right-handed neutrinos, which are part of the leptonic doublet of $SU(2)^\prime$, play the role of a long-lived unstable dark matter with mass in the multi-PeV range. We use a resonant $s$-channel annihilation to obtain the correct thermal relic density and relax the unitarity bound on dark matter mass. In this model, there exists a 3-body dark matter decay mode producing tau leptons and neutrinos, which could be the source for the PeV cascade events observed in the IceCube experiment. The model can be tested with more precise flavor information of the highest-energy neutrino events in future data. |
1409.6889 | Shoichi Kashiwase | Romy H. S. Budhi, Shoichi Kashiwase and Daijiro Suematsu | Inflation in a modified radiative seesaw model | 20 pages, 3 figures | Phys.Rev. D90 (2014) 113013 | 10.1103/PhysRevD.90.113013 | KANAZAWA-14-08 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The existence of the inflationary era in the early Universe seems to be
strongly supported by recent CMB observations. However, only a few realistic
inflation scenarios which have close relation to particle physics seem to have
been known unfortunately. The radiative neutrino mass model with inert doublet
dark matter is a promising model for the present experimental issues which
cannot be explained within the standard model. In order to make the model
include inflation, we extend it by a complex scalar field with a specific
potential. This scalar could be closely related to the neutrino mass generation
at a TeV scale as well as inflation. We show that the inflation favored by the
CMB observations could be realized even if inflaton takes sub-Planck values
during inflation.
| [
{
"created": "Wed, 24 Sep 2014 10:33:05 GMT",
"version": "v1"
},
{
"created": "Thu, 1 Jan 2015 02:51:17 GMT",
"version": "v2"
}
] | 2015-01-05 | [
[
"Budhi",
"Romy H. S.",
""
],
[
"Kashiwase",
"Shoichi",
""
],
[
"Suematsu",
"Daijiro",
""
]
] | The existence of the inflationary era in the early Universe seems to be strongly supported by recent CMB observations. However, only a few realistic inflation scenarios which have close relation to particle physics seem to have been known unfortunately. The radiative neutrino mass model with inert doublet dark matter is a promising model for the present experimental issues which cannot be explained within the standard model. In order to make the model include inflation, we extend it by a complex scalar field with a specific potential. This scalar could be closely related to the neutrino mass generation at a TeV scale as well as inflation. We show that the inflation favored by the CMB observations could be realized even if inflaton takes sub-Planck values during inflation. |
hep-ph/0007265 | Alessandro Strumia | Riccardo Barbieri and Alessandro Strumia | The `LEP paradox' | 4 pages. Talk given at the IVth Rencontres du Vietnam, July 2000 v2:
fit in table 1 repeated with updated data for m_higgs, m_W | null | null | IFUP-TH/2000-22 and SNS-PH/00-12 | hep-ph | null | Is there a Higgs? Where is it? Is supersymmetry there? Where is it? By
discussing these questions, we call attention to the `LEP paradox', which is
how we see the naturalness problem of the Fermi scale after a decade of
electroweak precision measurements, mostly done at LEP.
| [
{
"created": "Mon, 24 Jul 2000 20:32:17 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Nov 2000 17:00:45 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Barbieri",
"Riccardo",
""
],
[
"Strumia",
"Alessandro",
""
]
] | Is there a Higgs? Where is it? Is supersymmetry there? Where is it? By discussing these questions, we call attention to the `LEP paradox', which is how we see the naturalness problem of the Fermi scale after a decade of electroweak precision measurements, mostly done at LEP. |
hep-ph/0511255 | Yuelong Shen | Cai-Dian L\"u, Yue-Long Shen and Wei Wang | Final State Interaction In $B\to KK$ Decays | null | Phys.Rev.D73:034005,2006 | 10.1103/PhysRevD.73.034005 | null | hep-ph | null | We study the final state interaction effects in $B\to KK$ decays. We find
that the $t$ channel one-particle-exchange diagrams cannot enhance the
branching ratios of $\bar{B^0}\to K^0\bar{K^0}$ and $B^-\to K^0K^-$ very
sizably. For the pure annihilation process $\bar{B^0}\to K^+K^-$, the obtained
branching ratio by final state interaction is at ${\cal{O}}(10^{-8})$.
| [
{
"created": "Tue, 22 Nov 2005 14:21:38 GMT",
"version": "v1"
},
{
"created": "Wed, 8 Feb 2006 08:01:07 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Lü",
"Cai-Dian",
""
],
[
"Shen",
"Yue-Long",
""
],
[
"Wang",
"Wei",
""
]
] | We study the final state interaction effects in $B\to KK$ decays. We find that the $t$ channel one-particle-exchange diagrams cannot enhance the branching ratios of $\bar{B^0}\to K^0\bar{K^0}$ and $B^-\to K^0K^-$ very sizably. For the pure annihilation process $\bar{B^0}\to K^+K^-$, the obtained branching ratio by final state interaction is at ${\cal{O}}(10^{-8})$. |
1109.0309 | Chun Hay Kom | C. H. Kom, A. Kulesza, W. J. Stirling | Prospects for observation of double parton scattering with four-muon
final states at LHCb | 22 pages, 12 figures | null | 10.1140/epjc/s10052-011-1802-3 | Cavendish-HEP-2011/15, DAMTP-2011-56, TTK-11-27 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the prospects for observing double parton scattering through
four-muon final states, forming two opposite-sign muon pairs, in the LHCb
experiment in pp collisions at 14 TeV centre of mass energy. We consider two
special cases, namely double Drell-Yan and J/psi-pair production. The kinematic
properties and prospects for observing these processes are discussed. We find
that the production rate depends strongly on the origin of the four muons,
while many kinematic properties can be used to help identify the presence of
double parton scattering events.
| [
{
"created": "Thu, 1 Sep 2011 21:13:19 GMT",
"version": "v1"
}
] | 2015-05-30 | [
[
"Kom",
"C. H.",
""
],
[
"Kulesza",
"A.",
""
],
[
"Stirling",
"W. J.",
""
]
] | We study the prospects for observing double parton scattering through four-muon final states, forming two opposite-sign muon pairs, in the LHCb experiment in pp collisions at 14 TeV centre of mass energy. We consider two special cases, namely double Drell-Yan and J/psi-pair production. The kinematic properties and prospects for observing these processes are discussed. We find that the production rate depends strongly on the origin of the four muons, while many kinematic properties can be used to help identify the presence of double parton scattering events. |
1202.3026 | Qiang Zhao | Qian Wang, Xiao-Hai Liu, and Qiang Zhao | Updated study of the $\eta_c$ and $\eta_c^\prime$ decays into light
vector mesons | 11 pages, 4 eps figures; Improved formulation based on
1010.1343[hep-ph]; Revised version accepted by Phys. Lett. B | null | 10.1016/j.physletb.2012.04.022 | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We re-investigate the exclusive decays of $\eta_c$ and $\eta_c^\prime$ to a
pair of light vector mesons, i.e. $\eta_c (\eta_c')\to VV$. The long-distance
intermediate meson loop (IML) effects are evaluated as a non-perturbative
mechanism in addition to the short-distance $c\bar{c}$ annihilation
contributions. We show that both processes can be reasonably well constrained
with the help of the available experimental data. Since $\eta_c$ and $\eta_c'$
are the spin-0 partners of $J/\psi$ and $\psi'$, respectively, our study is
useful for gaining insights into the pQCD helicity selection rule violations in
charmonium decays and the long-standing "$\rho\pi$ puzzle".
| [
{
"created": "Tue, 14 Feb 2012 12:55:37 GMT",
"version": "v1"
},
{
"created": "Tue, 27 Mar 2012 13:35:39 GMT",
"version": "v2"
}
] | 2015-06-04 | [
[
"Wang",
"Qian",
""
],
[
"Liu",
"Xiao-Hai",
""
],
[
"Zhao",
"Qiang",
""
]
] | We re-investigate the exclusive decays of $\eta_c$ and $\eta_c^\prime$ to a pair of light vector mesons, i.e. $\eta_c (\eta_c')\to VV$. The long-distance intermediate meson loop (IML) effects are evaluated as a non-perturbative mechanism in addition to the short-distance $c\bar{c}$ annihilation contributions. We show that both processes can be reasonably well constrained with the help of the available experimental data. Since $\eta_c$ and $\eta_c'$ are the spin-0 partners of $J/\psi$ and $\psi'$, respectively, our study is useful for gaining insights into the pQCD helicity selection rule violations in charmonium decays and the long-standing "$\rho\pi$ puzzle". |
2112.07578 | Matteo Becchetti | Matteo Becchetti, Francesco Moriello, Armin Schweitzer | Two-loop amplitude for mixed QCD-EW corrections to $gg \to Hg$ | 23 pages, 2 figures | null | 10.1007/JHEP04(2022)139 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We report on the two-loop amplitude computation for the mixed QCD-electroweak
corrections to the process $gg \to Hg$, with exact dependence on the
electroweak boson masses. This amplitude has been employed in the computation
of next-to-leading order (NLO) mixed QCD-electroweak corrections to the
Higgs-boson production rate in arXiv:2010.09451. The master integrals that
appear in the amplitude are evaluated by means of generalized power series
expansions, which allows for fast and high-precision numerical evaluation of
the amplitude in the physical phase-space, proving to be a powerful tool for
phenomenological applications.
| [
{
"created": "Tue, 14 Dec 2021 17:34:46 GMT",
"version": "v1"
}
] | 2022-05-11 | [
[
"Becchetti",
"Matteo",
""
],
[
"Moriello",
"Francesco",
""
],
[
"Schweitzer",
"Armin",
""
]
] | We report on the two-loop amplitude computation for the mixed QCD-electroweak corrections to the process $gg \to Hg$, with exact dependence on the electroweak boson masses. This amplitude has been employed in the computation of next-to-leading order (NLO) mixed QCD-electroweak corrections to the Higgs-boson production rate in arXiv:2010.09451. The master integrals that appear in the amplitude are evaluated by means of generalized power series expansions, which allows for fast and high-precision numerical evaluation of the amplitude in the physical phase-space, proving to be a powerful tool for phenomenological applications. |
1508.05397 | Ian Lewis | S. Dawson, I. M. Lewis | NLO Corrections to Double Higgs Production in the Higgs Singlet Model | 27 pages, 22 figures. References updated, typos fixed, and discussion
added to introduction, Section IVB, and conclusion. Version to appear in PRD | Phys. Rev. D 92, 094023 (2015) | 10.1103/PhysRevD.92.094023 | SLAC-PUB-16335 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Higgs pair production at the LHC from gluon fusion is small in the Standard
Model, but can be enhanced in models where a resonant enhancement is allowed.
We examine the effect of a resonant contribution from a second scalar arising
in a model with a gauge singlet scalar field in addition to the usual SU(2)
scalar doublet, with mass up to $M_H$~600 GeV and discuss the interference
effects in double Higgs production. We compute the NLO QCD corrections in the
large $m_t$ limit and show that they can significantly distort kinematic
distributions near the resonance peak.
| [
{
"created": "Fri, 21 Aug 2015 20:09:44 GMT",
"version": "v1"
},
{
"created": "Thu, 12 Nov 2015 19:03:13 GMT",
"version": "v2"
}
] | 2016-02-08 | [
[
"Dawson",
"S.",
""
],
[
"Lewis",
"I. M.",
""
]
] | Higgs pair production at the LHC from gluon fusion is small in the Standard Model, but can be enhanced in models where a resonant enhancement is allowed. We examine the effect of a resonant contribution from a second scalar arising in a model with a gauge singlet scalar field in addition to the usual SU(2) scalar doublet, with mass up to $M_H$~600 GeV and discuss the interference effects in double Higgs production. We compute the NLO QCD corrections in the large $m_t$ limit and show that they can significantly distort kinematic distributions near the resonance peak. |
0909.5629 | Patricio Marcos Crichigno | Marcos P. Crichigno and Edward Shuryak | Quantum Corrections to Multi-Quanta Higgs-Bags in the Standard Model | 11 pages, 8 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We argue that the Standard Model contains stable bound states with a
sufficiently large number N of heavy quanta -top quarks and gauge bosons W,Z-
of the form of collective "bags", with a strongly depleted value of the Higgs
VEV inside. More specifically, we study one-loop quantum corrections to a
generic model of them, assuming "quanta" are described by a complex scalar
field. We follow the practical formalism developed by Farhi et al. for the N=1
case, i.e. one particle in a bag, who found that for a very large Yukawa
coupling the classical bags are destabilized by quantum effects. We instead
study the problem with a coupling constant in the range of the Standard Model
for a large number of quanta N=50..5000. We calculated both classical and
one-loop effects and found that for such bags quantum corrections are small, of
the order of a few percents or less.
| [
{
"created": "Wed, 30 Sep 2009 14:57:57 GMT",
"version": "v1"
}
] | 2009-10-01 | [
[
"Crichigno",
"Marcos P.",
""
],
[
"Shuryak",
"Edward",
""
]
] | We argue that the Standard Model contains stable bound states with a sufficiently large number N of heavy quanta -top quarks and gauge bosons W,Z- of the form of collective "bags", with a strongly depleted value of the Higgs VEV inside. More specifically, we study one-loop quantum corrections to a generic model of them, assuming "quanta" are described by a complex scalar field. We follow the practical formalism developed by Farhi et al. for the N=1 case, i.e. one particle in a bag, who found that for a very large Yukawa coupling the classical bags are destabilized by quantum effects. We instead study the problem with a coupling constant in the range of the Standard Model for a large number of quanta N=50..5000. We calculated both classical and one-loop effects and found that for such bags quantum corrections are small, of the order of a few percents or less. |
1901.04322 | Snigdha Ghosh | Snigdha Ghosh and Vinod Chandra | Scattering cross-section under external magnetic field using the optical
theorem | Version published in European Physical Journal A | European Physical Journal A (2020) 56:190 | 10.1140/epja/s10050-020-00181-1 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The cross-section for the lowest order $2\rightarrow2$ elastic scattering
between two charged scalars under external magnetic field mediated via a
neutral scalar, has been computed in strong as well as weak magnetic field
limits. This has been done by applying the optical theorem where the
cross-section is expressed in terms of the imaginary parts of different
one-loop graphs contributing to the forward scattering amplitudes. The
modification in the amplitudes due to the external magnetic field has been done
by means of replacing the charged scalar propagators with the Schwinger
proper-time ones. Significant modifications of the cross-sections with respect
to the vacuum cross-section are observed due to the external magnetic field.
| [
{
"created": "Mon, 14 Jan 2019 13:56:01 GMT",
"version": "v1"
},
{
"created": "Wed, 25 Sep 2019 08:53:25 GMT",
"version": "v2"
},
{
"created": "Sat, 25 Jul 2020 05:27:48 GMT",
"version": "v3"
}
] | 2020-07-28 | [
[
"Ghosh",
"Snigdha",
""
],
[
"Chandra",
"Vinod",
""
]
] | The cross-section for the lowest order $2\rightarrow2$ elastic scattering between two charged scalars under external magnetic field mediated via a neutral scalar, has been computed in strong as well as weak magnetic field limits. This has been done by applying the optical theorem where the cross-section is expressed in terms of the imaginary parts of different one-loop graphs contributing to the forward scattering amplitudes. The modification in the amplitudes due to the external magnetic field has been done by means of replacing the charged scalar propagators with the Schwinger proper-time ones. Significant modifications of the cross-sections with respect to the vacuum cross-section are observed due to the external magnetic field. |
hep-ph/0212060 | XiaoHu Mo | P. Wang, X. H. Mo and C. Z. Yuan | The Form Factors of omega pi0 and pi+ pi- at psi(2S) | 6 pages, 1 figures(two diagrams), Phys. Lett. B557 (2003) 192-197 | Phys.Lett. B557 (2003) 192-197 | 10.1016/S0370-2693(03)00195-3 | null | hep-ph | null | The measurements of psi(2S) -> omega pi0 and psi(2S) -> pi+ pi- in e+e-
experiments are examined. It is found that the non-resonance virtual photon
annihilation gives large contributions to the observed cross sections of these
two processes. By including this contribution, the form factors and branching
fractions of these two decay modes are revised.
| [
{
"created": "Wed, 4 Dec 2002 09:05:44 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Mar 2003 00:39:23 GMT",
"version": "v2"
}
] | 2016-09-06 | [
[
"Wang",
"P.",
""
],
[
"Mo",
"X. H.",
""
],
[
"Yuan",
"C. Z.",
""
]
] | The measurements of psi(2S) -> omega pi0 and psi(2S) -> pi+ pi- in e+e- experiments are examined. It is found that the non-resonance virtual photon annihilation gives large contributions to the observed cross sections of these two processes. By including this contribution, the form factors and branching fractions of these two decay modes are revised. |
hep-ph/9608220 | Aida El-Khadra | Aida X. El-Khadra (University of Illinois) | $\alpha_s$ with Lattice QCD | 9 pages, 3 figures (included), LaTeX, needs sprocl.sty and epsf.sty.
To appear in the proceedings of the XXXIst Rencontre de Moriond on
Electroweak Interactions and Unified Theories, Les Arcs 1800, France, March
16-23, 1996 | null | null | ILL-TH-96-05 | hep-ph | null | The status of determinations of the strong coupling constant based on lattice
QCD is reviewed.
| [
{
"created": "Fri, 2 Aug 1996 16:52:05 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"El-Khadra",
"Aida X.",
"",
"University of Illinois"
]
] | The status of determinations of the strong coupling constant based on lattice QCD is reviewed. |
hep-ph/0606209 | Xavier Calmet | Xavier Calmet, Josep F. Oliver | A Seesaw Mechanism in the Higgs Sector | 10 pages | Europhys.Lett.77:51002,2007 | 10.1209/0295-5075/77/51002 | ULB-TH/06-16 | hep-ph astro-ph | null | In this letter we revisit the seesaw Higgs mechanism. We show how a seesaw
mechanism in a two Higgs doublets model can trigger the electroweak symmetry
breaking if at least one of the eigenvalues of the squared mass matrix is
negative. We then consider two special cases of interest. In the decoupling
scenario, there is only one scalar degree of freedom in the low energy regime.
In the degenerate scenario, all five degrees of freedom are in the low energy
regime and will lead to observables effects at the LHC. Furthermore, in that
scenario, it is possible to impose a discrete symmetry between the doublets
that makes the extra neutral degrees of freedom stable. These are thus viable
dark matter candidates. We find an interesting relation between the electroweak
symmetry breaking mechanism and dark matter.
| [
{
"created": "Tue, 20 Jun 2006 09:15:49 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Calmet",
"Xavier",
""
],
[
"Oliver",
"Josep F.",
""
]
] | In this letter we revisit the seesaw Higgs mechanism. We show how a seesaw mechanism in a two Higgs doublets model can trigger the electroweak symmetry breaking if at least one of the eigenvalues of the squared mass matrix is negative. We then consider two special cases of interest. In the decoupling scenario, there is only one scalar degree of freedom in the low energy regime. In the degenerate scenario, all five degrees of freedom are in the low energy regime and will lead to observables effects at the LHC. Furthermore, in that scenario, it is possible to impose a discrete symmetry between the doublets that makes the extra neutral degrees of freedom stable. These are thus viable dark matter candidates. We find an interesting relation between the electroweak symmetry breaking mechanism and dark matter. |
hep-ph/0410038 | Junji Hisano | Junji Hisano | CP violation in supersymmetric seesaw models | Talk given at SEESAW25: International Conference On The Seesaw
Mechanism And The Neutrino Mass 10-11 Jun 2004, Paris, France | null | 10.1142/9789812702210_0009 | null | hep-ph | null | In supersymmetric (SUSY) extensions of the seesaw mechanism the neutrino
Yukawa interaction induces the flavor and CP violating sfermion mass terms via
the radiative correction. In this article we review the CP violating phenomena
in the SUSY seesaw models.
| [
{
"created": "Sun, 3 Oct 2004 05:31:28 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Hisano",
"Junji",
""
]
] | In supersymmetric (SUSY) extensions of the seesaw mechanism the neutrino Yukawa interaction induces the flavor and CP violating sfermion mass terms via the radiative correction. In this article we review the CP violating phenomena in the SUSY seesaw models. |
hep-ph/0603188 | Vyacheslav Rychkov | Riccardo Barbieri, Lawrence J. Hall, Vyacheslav S. Rychkov | Improved Naturalness with a Heavy Higgs: An Alternative Road to LHC
Physics | 25 pages; v2: published version (a reference added, minor
corrections) | Phys.Rev.D74:015007,2006 | 10.1103/PhysRevD.74.015007 | UCB-PTH-06/04, LBNL-59894 | hep-ph | null | The quadratic divergences of the Higgs mass may be cancelled either
accidentally or by the exchange of some new particles. Alternatively its impact
on naturalness may be weakened by raising the Higgs mass, which requires
changing the Standard Model below its natural cut-off. We show in detail how
this can be achieved, while preserving perturbativity and consistency with the
electroweak precision tests, by extending the Standard Model to include a
second Higgs doublet that has neither a vev nor couplings to quarks and
leptons. This Inert Doublet Model yields a perturbative and completely natural
description of electroweak physics at all energies up to 1.5 TeV. The discrete
symmetry that yields the Inert Doublet is unbroken, so that Dark Matter may be
composed of neutral inert Higgs bosons, which may have escaped detection at
LEP2. Predictions are given for multilepton events with missing transverse
energy at the Large Hadron Collider, and for the direct detection of dark
matter.
| [
{
"created": "Thu, 23 Mar 2006 09:31:05 GMT",
"version": "v1"
},
{
"created": "Mon, 24 Jul 2006 08:21:29 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Barbieri",
"Riccardo",
""
],
[
"Hall",
"Lawrence J.",
""
],
[
"Rychkov",
"Vyacheslav S.",
""
]
] | The quadratic divergences of the Higgs mass may be cancelled either accidentally or by the exchange of some new particles. Alternatively its impact on naturalness may be weakened by raising the Higgs mass, which requires changing the Standard Model below its natural cut-off. We show in detail how this can be achieved, while preserving perturbativity and consistency with the electroweak precision tests, by extending the Standard Model to include a second Higgs doublet that has neither a vev nor couplings to quarks and leptons. This Inert Doublet Model yields a perturbative and completely natural description of electroweak physics at all energies up to 1.5 TeV. The discrete symmetry that yields the Inert Doublet is unbroken, so that Dark Matter may be composed of neutral inert Higgs bosons, which may have escaped detection at LEP2. Predictions are given for multilepton events with missing transverse energy at the Large Hadron Collider, and for the direct detection of dark matter. |
hep-ph/0009231 | Kang-young Lee | C. S. Kim (Yonsei U., U. of Wisconsin), Kang Young Lee (KIAS) and
Jeonghyeon Song (KIAS) | Enhancement of the Higgs pair production at LHC; the MSSM and extra
dimension effects | Revised version, 26 pages including 11 figures, ReVTeX | Phys.Rev.D64:015009,2001 | 10.1103/PhysRevD.64.015009 | YUMS 00-09, KIAS-P00060, SNUTP 00-024 | hep-ph | null | The neutral Higgs pair production at the LHC is studied in the MSSM, the
large extra dimensional (ADD) model and the Randall-Sundrum (RS) model, where
the total cross section can be significantly enhanced compared to that in the
SM. The $p_{_T}$, invariant mass and rapidity distributions of each model have
been shown to be distinctive: The ADD model raises the $p_T$ and invariant mass
distributions at high scales of $p_T$ and invariant mass; in the RS model
resonant peaks appear after the SM contribution dies away; the SM and the MSSM
distributions drop rapidly at those high scales; in the ADD and the RS models
the rapidity distributions congregate more around the center. It is concluded
that various distributions of the Higgs pair production at the LHC with
restrictive kinematic cuts would provide one of the most robust signals for the
extra dimensional effects.
| [
{
"created": "Wed, 20 Sep 2000 02:08:21 GMT",
"version": "v1"
},
{
"created": "Mon, 29 Jan 2001 10:01:21 GMT",
"version": "v2"
}
] | 2009-09-25 | [
[
"Kim",
"C. S.",
"",
"Yonsei U., U. of Wisconsin"
],
[
"Lee",
"Kang Young",
"",
"KIAS"
],
[
"Song",
"Jeonghyeon",
"",
"KIAS"
]
] | The neutral Higgs pair production at the LHC is studied in the MSSM, the large extra dimensional (ADD) model and the Randall-Sundrum (RS) model, where the total cross section can be significantly enhanced compared to that in the SM. The $p_{_T}$, invariant mass and rapidity distributions of each model have been shown to be distinctive: The ADD model raises the $p_T$ and invariant mass distributions at high scales of $p_T$ and invariant mass; in the RS model resonant peaks appear after the SM contribution dies away; the SM and the MSSM distributions drop rapidly at those high scales; in the ADD and the RS models the rapidity distributions congregate more around the center. It is concluded that various distributions of the Higgs pair production at the LHC with restrictive kinematic cuts would provide one of the most robust signals for the extra dimensional effects. |
1103.3280 | Jorge de Blas Mateo | J. de Blas, A. Delgado | Exploring singlet deflection of gauge mediation | Latex 18 pages, 4 eps figures. Minor corrections, version published
in Phys. Rev. D | Phys.Rev.D83:115011,2011 | 10.1103/PhysRevD.83.115011 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We embed the Next-to Minimal Supersymmetric Standard Model into gauge
mediation of supersymmetry breaking and study the phenomenology of scenarios
where the gauge-mediation contributions to soft parameters are deflected by
superpotential interactions of the gauge singlet with the messenger fields and
the Higgs doublets. This kind of models provide a satisfactory solution to the
mu-b_mu problem of gauge mediation, compatible with the adequate pattern of
electroweak symmetry breaking and a realistic spectrum with supersymmetric
partners at the TeV scale without requiring a significant fine tuning.
| [
{
"created": "Wed, 16 Mar 2011 20:03:39 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Jun 2011 20:07:01 GMT",
"version": "v2"
}
] | 2011-06-30 | [
[
"de Blas",
"J.",
""
],
[
"Delgado",
"A.",
""
]
] | We embed the Next-to Minimal Supersymmetric Standard Model into gauge mediation of supersymmetry breaking and study the phenomenology of scenarios where the gauge-mediation contributions to soft parameters are deflected by superpotential interactions of the gauge singlet with the messenger fields and the Higgs doublets. This kind of models provide a satisfactory solution to the mu-b_mu problem of gauge mediation, compatible with the adequate pattern of electroweak symmetry breaking and a realistic spectrum with supersymmetric partners at the TeV scale without requiring a significant fine tuning. |
hep-ph/0606256 | Lev Kofman | Gary N. Felder and Lev Kofman | Nonlinear Inflaton Fragmentation after Preheating | 9 pages, 6 figs | Phys.Rev.D75:043518,2007 | 10.1103/PhysRevD.75.043518 | null | hep-ph astro-ph hep-th | null | We consider the nonlinear dynamics of inflaton fragmentation during and after
preheating in the simplest model of chaotic inflation. While the earlier regime
of parametric resonant particle production and the later turbulent regime of
interacting fields evolving towards equilibrium are well identified and
understood, the short intermediate stage of violent nonlinear dynamics remains
less explored. Lattice simulations of fully nonlinear preheating dynamics show
specific features of this intermediate stage: occupation numbers of the scalar
particles are peaked, scalar fields become significantly non-gaussian and the
field dynamics become chaotic and irreversible. Visualization of the field
dynamics in configuration space reveals that nonlinear interactions generate
non-gaussian inflaton inhomogeneities with very fast growing amplitudes. The
peaks of the inflaton inhomogeneities coincide with the peaks of the scalar
field(s) produced by parametric resonance. When the inflaton peaks reach their
maxima, they stop growing and begin to expand. The subsequent dynamics is
determined by expansion and superposition of the scalar waves originating from
the peaks. Multiple wave superposition results in phase mixing and turbulent
wave dynamics. Thus, the short intermediate stage is defined by the formation,
expansion and collision of bubble-like field inhomogeneities associated with
the peaks of the original gaussian field. This process is qualitatively similar
to the bubble-like inflaton fragmentation that occurs during tachyonic
preheating after hybrid or new inflation.
| [
{
"created": "Mon, 26 Jun 2006 19:02:45 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Felder",
"Gary N.",
""
],
[
"Kofman",
"Lev",
""
]
] | We consider the nonlinear dynamics of inflaton fragmentation during and after preheating in the simplest model of chaotic inflation. While the earlier regime of parametric resonant particle production and the later turbulent regime of interacting fields evolving towards equilibrium are well identified and understood, the short intermediate stage of violent nonlinear dynamics remains less explored. Lattice simulations of fully nonlinear preheating dynamics show specific features of this intermediate stage: occupation numbers of the scalar particles are peaked, scalar fields become significantly non-gaussian and the field dynamics become chaotic and irreversible. Visualization of the field dynamics in configuration space reveals that nonlinear interactions generate non-gaussian inflaton inhomogeneities with very fast growing amplitudes. The peaks of the inflaton inhomogeneities coincide with the peaks of the scalar field(s) produced by parametric resonance. When the inflaton peaks reach their maxima, they stop growing and begin to expand. The subsequent dynamics is determined by expansion and superposition of the scalar waves originating from the peaks. Multiple wave superposition results in phase mixing and turbulent wave dynamics. Thus, the short intermediate stage is defined by the formation, expansion and collision of bubble-like field inhomogeneities associated with the peaks of the original gaussian field. This process is qualitatively similar to the bubble-like inflaton fragmentation that occurs during tachyonic preheating after hybrid or new inflation. |
2208.14469 | Tetyana Pitik | Tetyana Pitik, Daniel Heimsoth, Anna M. Suliga, and A. B. Balantekin | Exploiting stellar explosion induced by the QCD phase transition in
large-scale neutrino detectors | 19 pages, 9 figures, 3 appendices. Minor clarifications added,
matches version published in Phys. Rev. D | Phys. Rev. D 106, 103007 (2022) | 10.1103/PhysRevD.106.103007 | N3AS-22-011 | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The centers of the core-collapse supernovae are one of the densest
environments in the Universe. Under such conditions, it is conceivable that a
first-order phase transition from ordinary nuclear matter to the quark-gluon
plasma occurs. This transition releases a large amount of latent heat that can
drive a supernova explosion and may imprint a sharp signature in the neutrino
signal. We show how this snap feature, if observed at large-scale neutrino
detectors, can set competitive limits on the neutrino masses and assist the
localization of the supernova via triangulation. The 95\%C.L. limit on the
neutrino mass can reach 0.16~eV in Ice-Cube, 0.22~eV in Hyper-Kamiokande, and
0.58~eV in DUNE, for a supernova at a distance of 10 kpc. For the same distance
and in the most optimistic neutrino conversion case, the triangulation method
can constrain the $1\sigma$ angular uncertainty of the supernova localization
within $\sim 0.3^{\circ}-9.0^{\circ}$ in the considered pairs of the detectors,
leading to an improvement up to an order of magnitude with respect to the often
considered in the literature rise time of the neutronization burst.
| [
{
"created": "Tue, 30 Aug 2022 18:00:16 GMT",
"version": "v1"
},
{
"created": "Fri, 4 Nov 2022 17:58:09 GMT",
"version": "v2"
}
] | 2022-11-07 | [
[
"Pitik",
"Tetyana",
""
],
[
"Heimsoth",
"Daniel",
""
],
[
"Suliga",
"Anna M.",
""
],
[
"Balantekin",
"A. B.",
""
]
] | The centers of the core-collapse supernovae are one of the densest environments in the Universe. Under such conditions, it is conceivable that a first-order phase transition from ordinary nuclear matter to the quark-gluon plasma occurs. This transition releases a large amount of latent heat that can drive a supernova explosion and may imprint a sharp signature in the neutrino signal. We show how this snap feature, if observed at large-scale neutrino detectors, can set competitive limits on the neutrino masses and assist the localization of the supernova via triangulation. The 95\%C.L. limit on the neutrino mass can reach 0.16~eV in Ice-Cube, 0.22~eV in Hyper-Kamiokande, and 0.58~eV in DUNE, for a supernova at a distance of 10 kpc. For the same distance and in the most optimistic neutrino conversion case, the triangulation method can constrain the $1\sigma$ angular uncertainty of the supernova localization within $\sim 0.3^{\circ}-9.0^{\circ}$ in the considered pairs of the detectors, leading to an improvement up to an order of magnitude with respect to the often considered in the literature rise time of the neutronization burst. |
0808.1854 | A. Cooper-Sarkar | A M Cooper-Sarkar | Extraction of the proton parton density functions using a NLO-QCD fit of
the combined H1 and ZEUS inclusive DIS cross sections | 5 pages, 2 figures. Talk on behalf of H1 and ZEUS collaborations, to
be published in the Proceedings of the 16th Workshop on Deep Inelastic
Scattering, DIS2008, London, April 7-11th 2008 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The combined HERA-I data set, of neutral and charged current inclusive
cross-sections for $e^+p$ and $e^-p$ scattering, is used as the sole input for
a next-to-leading order (NLO) QCD parton distribution function (PDF) fit. The
consistent treatment of systematic uncertainties in the joint data set ensures
that experimental uncertainties on the PDFs can be calculated without need for
an increased $\chi^2$ tolerance. This results in PDFs with greatly reduced
experimental uncertainties compared to the separate analyses of the ZEUS and H1
experiments. Model uncertainties, including those arising from parametrization
dependence, are also carefully considered. The resulting HERAPDFs have
impressive precision compared to the global fits.
| [
{
"created": "Wed, 13 Aug 2008 15:51:34 GMT",
"version": "v1"
}
] | 2008-08-14 | [
[
"Cooper-Sarkar",
"A M",
""
]
] | The combined HERA-I data set, of neutral and charged current inclusive cross-sections for $e^+p$ and $e^-p$ scattering, is used as the sole input for a next-to-leading order (NLO) QCD parton distribution function (PDF) fit. The consistent treatment of systematic uncertainties in the joint data set ensures that experimental uncertainties on the PDFs can be calculated without need for an increased $\chi^2$ tolerance. This results in PDFs with greatly reduced experimental uncertainties compared to the separate analyses of the ZEUS and H1 experiments. Model uncertainties, including those arising from parametrization dependence, are also carefully considered. The resulting HERAPDFs have impressive precision compared to the global fits. |
1405.5700 | Toshinori Matsui | Toshinori Matsui | Higgs inflation scenario in a radiative seesaw model and its testability
at the ILC | 6 pages, 6 figures. Talk presented at the International Workshop on
Future Linear Colliders (LCWS13), Tokyo, Japan, 11-15 November 2013 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Higgs inflation scenario is an approach to realize the cosmic inflation,
where the Higgs boson plays a role of the inflaton. In the minimal model, it
would be difficult to satisfy theoretical constraints from vacuum stability and
perturbative unitarity. These problems can be solved by considering multi-Higgs
models. In this talk, we discuss a Higgs inflation scenario in a radiative
seesaw model with an inert doublet, which originally has been proposed to
explain dark matter and neutrino masses. We study this model under the
constraints from the current data, and find parameter regions where additional
scalar bosons can play a role of inflatons. They satisfy the current data from
neutrino experiments, the dark matter searches and also from LEP and LHC. A
unique phenomenological prediction appears in the mass spectrum of inert scalar
bosons. We show that this scenario is challenging to be tested at the LHC, but
would be well testable at the International Liner Collider by measuring
endpoints of energy distribution of a two jet system from decay processes of
the inert scalar fields produced via pair production.
| [
{
"created": "Thu, 22 May 2014 10:09:14 GMT",
"version": "v1"
}
] | 2014-05-23 | [
[
"Matsui",
"Toshinori",
""
]
] | The Higgs inflation scenario is an approach to realize the cosmic inflation, where the Higgs boson plays a role of the inflaton. In the minimal model, it would be difficult to satisfy theoretical constraints from vacuum stability and perturbative unitarity. These problems can be solved by considering multi-Higgs models. In this talk, we discuss a Higgs inflation scenario in a radiative seesaw model with an inert doublet, which originally has been proposed to explain dark matter and neutrino masses. We study this model under the constraints from the current data, and find parameter regions where additional scalar bosons can play a role of inflatons. They satisfy the current data from neutrino experiments, the dark matter searches and also from LEP and LHC. A unique phenomenological prediction appears in the mass spectrum of inert scalar bosons. We show that this scenario is challenging to be tested at the LHC, but would be well testable at the International Liner Collider by measuring endpoints of energy distribution of a two jet system from decay processes of the inert scalar fields produced via pair production. |
2311.02022 | Li-Sheng Geng | Tian-Chen Wu, Atsushi Hosaka, and Li-Sheng Geng | Production of the $\Xi N$ dibaryon as a weakly bound system in $pp$
collisions | 7 pages, 6 figures; comments welcome | null | null | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The $\Xi N$ interaction plays an important role in our understanding on the
long-anticipated $H$-dibaryon. Recent lattice QCD calculations verified the
attractive nature of the $\Xi N$ interaction. On the other hand, whether it is
strong enough to generate a bound state remains inconclusive.In this work,
assuming that it can generate a weakly bound state, we study the yields of the
$\Xi N$ dibaryon for different binding energies in $pp$ collisions at 7 TeV
using the coalescence model and the transport model PACIAE. The yields are
estimated first numerically and then analytically adopting a Yukawa-type wave
function. In particular, we find that in the weak binding limit, there exists a
universal relation between the yield and the binding energy, valid for $pp$
collisions.
| [
{
"created": "Fri, 3 Nov 2023 16:35:00 GMT",
"version": "v1"
}
] | 2023-11-06 | [
[
"Wu",
"Tian-Chen",
""
],
[
"Hosaka",
"Atsushi",
""
],
[
"Geng",
"Li-Sheng",
""
]
] | The $\Xi N$ interaction plays an important role in our understanding on the long-anticipated $H$-dibaryon. Recent lattice QCD calculations verified the attractive nature of the $\Xi N$ interaction. On the other hand, whether it is strong enough to generate a bound state remains inconclusive.In this work, assuming that it can generate a weakly bound state, we study the yields of the $\Xi N$ dibaryon for different binding energies in $pp$ collisions at 7 TeV using the coalescence model and the transport model PACIAE. The yields are estimated first numerically and then analytically adopting a Yukawa-type wave function. In particular, we find that in the weak binding limit, there exists a universal relation between the yield and the binding energy, valid for $pp$ collisions. |
hep-ph/0301226 | Ernest Jankowski | D. Yu. Grigoriev, E. Jankowski, F. V. Tkachov | Optimal Jet Finder | version to appear in Comp. Phys. Commun., 36 pages | Comput.Phys.Commun. 155 (2003) 42-64 | 10.1016/S0010-4655(03)00291-1 | Alberta Thy 02-03 | hep-ph | null | We describe a FORTRAN 77 implementation of the optimal jet definition for
identification of jets in hadronic final states of particle collisions. We
discuss details of the implementation, explain interface subroutines and
provide a usage example. The source code is available from
http://www.inr.ac.ru/~ftkachov/projects/jets/
| [
{
"created": "Sun, 26 Jan 2003 21:41:59 GMT",
"version": "v1"
},
{
"created": "Mon, 23 Jun 2003 23:01:12 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Grigoriev",
"D. Yu.",
""
],
[
"Jankowski",
"E.",
""
],
[
"Tkachov",
"F. V.",
""
]
] | We describe a FORTRAN 77 implementation of the optimal jet definition for identification of jets in hadronic final states of particle collisions. We discuss details of the implementation, explain interface subroutines and provide a usage example. The source code is available from http://www.inr.ac.ru/~ftkachov/projects/jets/ |
hep-ph/0106019 | Pietro Faccioli | P.Faccioli, E.V. Shuryak | Systematic Study of the Single Instanton Approximation in QCD | 11 pages, 4 figures, version submitted to Phys. Rev. D | Phys.Rev. D64 (2001) 114020 | 10.1103/PhysRevD.64.114020 | null | hep-ph | null | The Single-instanton approximation (SIA) is often used to evaluate
analytically instanton contribution to euclidean correlation functions in QCD,
at small distances. We discuss how this approximation can be consistently
derived from the theory of the instanton ensemble and give precise definitions
to a number of different "effective masses", generalizing the parameter $m*$,
which was introduced long ago to account for the collective contribution of the
whole ensemble.
We test numerically the range of applicability of the SIA for different
quantities. Furthermore, we determine all the effective masses (for random and
interacting instanton liquid models) as well as from phenomenology, and discuss
to what extent those are universal.
| [
{
"created": "Fri, 1 Jun 2001 19:54:56 GMT",
"version": "v1"
},
{
"created": "Tue, 31 Jul 2001 14:49:17 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Faccioli",
"P.",
""
],
[
"Shuryak",
"E. V.",
""
]
] | The Single-instanton approximation (SIA) is often used to evaluate analytically instanton contribution to euclidean correlation functions in QCD, at small distances. We discuss how this approximation can be consistently derived from the theory of the instanton ensemble and give precise definitions to a number of different "effective masses", generalizing the parameter $m*$, which was introduced long ago to account for the collective contribution of the whole ensemble. We test numerically the range of applicability of the SIA for different quantities. Furthermore, we determine all the effective masses (for random and interacting instanton liquid models) as well as from phenomenology, and discuss to what extent those are universal. |
hep-ph/0509369 | Chong Sheng Li | Jun Zhao, Chong Sheng Li, Qiang Li | SUSY-QCD Corrections to $W^{\pm}H^{\mp}$ Associated Production at the
CERN Large Hadron Collider | 24 pages, 10 figures; minor changes in references; two figures and
the corresponding disccusions added; a version to appear in PRD | Phys.Rev. D72 (2005) 114008 | 10.1103/PhysRevD.72.114008 | null | hep-ph | null | We calculate the SUSY-QCD corrections to the inclusive total cross sections
of the associated production processes $pp\to W^{\pm}H^{\mp}+X$ in the Minimal
Supersymmetric Standard Model(MSSM) at the CERN Large Hadron Collider(LHC). The
SUSY-QCD corrections can increase and decrease the total cross sections
depending on the choice of the SUSY parameters. When $\mu<0$ the SUSY-QCD
corrections increase the leading-order (LO) total cross sections significantly
for large tan$\beta$ ($\sim 40$), which can exceed 10% and have the opposite
sign with respect to the QCD and the SUSY-EW corrections, and thus cancel with
them to some extent. Moreover, we also investigate the effects of the SUSY-QCD
on the differential distribution of cross sections in transverse momentum $p_T$
and rapidity Y of W-boson, and the invariant mass $M_{W^+H^-}$.
| [
{
"created": "Fri, 30 Sep 2005 15:34:03 GMT",
"version": "v1"
},
{
"created": "Wed, 7 Dec 2005 15:20:44 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Zhao",
"Jun",
""
],
[
"Li",
"Chong Sheng",
""
],
[
"Li",
"Qiang",
""
]
] | We calculate the SUSY-QCD corrections to the inclusive total cross sections of the associated production processes $pp\to W^{\pm}H^{\mp}+X$ in the Minimal Supersymmetric Standard Model(MSSM) at the CERN Large Hadron Collider(LHC). The SUSY-QCD corrections can increase and decrease the total cross sections depending on the choice of the SUSY parameters. When $\mu<0$ the SUSY-QCD corrections increase the leading-order (LO) total cross sections significantly for large tan$\beta$ ($\sim 40$), which can exceed 10% and have the opposite sign with respect to the QCD and the SUSY-EW corrections, and thus cancel with them to some extent. Moreover, we also investigate the effects of the SUSY-QCD on the differential distribution of cross sections in transverse momentum $p_T$ and rapidity Y of W-boson, and the invariant mass $M_{W^+H^-}$. |
1010.2945 | Daniele Binosi | Daniele Binosi | The IR sector of QCD: lattice versus Schwinger-Dyson equations | 6 pages. Talk given at QCD@Work 2010 -International Workshop on QCD:
Theory and Experiment-, 20-23 June 2010, Martina Franca, Valle d'Itria
(Italy) | AIP Conf.Proc.1317:168-173,2011 | 10.1063/1.3536552 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Important information about the infrared dynamics of QCD is encoded in the
behavior of its (of-shell) Green's functions, most notably the gluon and the
ghost propagators. Due to recent improvements in the quality of lattice data
and the truncation schemes employed for the Schwinger-Dyson equations we have
now reached a point where the interplay between these two non-perturbative
tools can be most fruitful. In this talk several of the above points will be
reviewed, with particular emphasis on the implications for the ghost sector,
the non-perturbative effective charge of QCD, and the Kugo-Ojima function.
| [
{
"created": "Thu, 14 Oct 2010 15:02:34 GMT",
"version": "v1"
}
] | 2011-02-01 | [
[
"Binosi",
"Daniele",
""
]
] | Important information about the infrared dynamics of QCD is encoded in the behavior of its (of-shell) Green's functions, most notably the gluon and the ghost propagators. Due to recent improvements in the quality of lattice data and the truncation schemes employed for the Schwinger-Dyson equations we have now reached a point where the interplay between these two non-perturbative tools can be most fruitful. In this talk several of the above points will be reviewed, with particular emphasis on the implications for the ghost sector, the non-perturbative effective charge of QCD, and the Kugo-Ojima function. |
2010.03912 | Vitaly Okorokov A | V. A. Okorokov (National Research Nuclear University MEPhI) | Top pair production at ultra-high energies | 6 pages, 2 figures. 5th International conference on particle physics
and astrophysics (ICPPA2020). Moscow, Russia, October 5-9, 2020 | J. Phys.: Conf. Ser. 1690, 012006, 2020 | 10.1088/1742-6596/1690/1/012006 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The top quark, the heaviest quark and, indeed, the heaviest elementary
particle known today, constitutes a novel probe of the long-lived medium in
quark-gluon phase which, as expected, can be produced even in light nuclei
collisions at ultra-high energies. Some distinctive features are considered for
particle production in the top sector in ultra-high energy domain. The
antitop-top pair production is studied within the quantum chromodynamics and
effective field theory approach used for calculations of total partonic cross
sections. Predictions for all observables are computed at NNLO in quantum
chromodynamics and at LO in effective field theory. These quantitative results
can be important for both the future collider experiments at center-of-mass
energy frontier and the improvement of the phenomenological models for
development of the cosmic ray cascades in ultra-high energy domain. Thus the
study allows the better understanding of heavy particle production and
emphasizes the exciting interrelation between the high-energy physics on
accelerators and ultra-high energy cosmic ray measurements.
| [
{
"created": "Thu, 8 Oct 2020 11:53:12 GMT",
"version": "v1"
},
{
"created": "Thu, 17 Dec 2020 04:33:45 GMT",
"version": "v2"
}
] | 2020-12-18 | [
[
"Okorokov",
"V. A.",
"",
"National Research Nuclear University MEPhI"
]
] | The top quark, the heaviest quark and, indeed, the heaviest elementary particle known today, constitutes a novel probe of the long-lived medium in quark-gluon phase which, as expected, can be produced even in light nuclei collisions at ultra-high energies. Some distinctive features are considered for particle production in the top sector in ultra-high energy domain. The antitop-top pair production is studied within the quantum chromodynamics and effective field theory approach used for calculations of total partonic cross sections. Predictions for all observables are computed at NNLO in quantum chromodynamics and at LO in effective field theory. These quantitative results can be important for both the future collider experiments at center-of-mass energy frontier and the improvement of the phenomenological models for development of the cosmic ray cascades in ultra-high energy domain. Thus the study allows the better understanding of heavy particle production and emphasizes the exciting interrelation between the high-energy physics on accelerators and ultra-high energy cosmic ray measurements. |
hep-ph/0403091 | Kenji Fukushima | Kenji Fukushima | Quark description of the Nambu-Goldstone bosons in the color-flavor
locked phase | 14 pages, 1 table, 1 figure and confusing statements are corrected | Phys.Rev. D70 (2004) 094014 | 10.1103/PhysRevD.70.094014 | MIT-CTP 3479 | hep-ph | null | We investigate the color-singlet order parameters and the quark description
of the Nambu-Goldstone (NG) bosons in the color-flavor locked (CFL) phase. We
put emphasis on the NG boson (phason) called ``H'' associated with the
$\mathrm{U_B(1)}$ symmetry breaking. We qualitatively argue the nature of H as
the second sound in the hydrodynamic regime. We articulate, based on a diquark
picture, how the structural change of the condensates and the associated NG
bosons occurs continuously from hadronic to CFL quark matter if the
quark-hadron continuity is realized. We sharpen the qualitative difference
between the flavor octet pions and the singlet phason. We propose a conjecture
that superfluid H matter undergoes a crossover to a superconductor with
tightly-bound diquarks, and then a crossover to superconducting matter with
diquarks dissociated.
| [
{
"created": "Tue, 9 Mar 2004 05:04:23 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Mar 2004 23:08:54 GMT",
"version": "v2"
},
{
"created": "Sun, 5 Sep 2004 21:35:04 GMT",
"version": "v3"
}
] | 2009-11-10 | [
[
"Fukushima",
"Kenji",
""
]
] | We investigate the color-singlet order parameters and the quark description of the Nambu-Goldstone (NG) bosons in the color-flavor locked (CFL) phase. We put emphasis on the NG boson (phason) called ``H'' associated with the $\mathrm{U_B(1)}$ symmetry breaking. We qualitatively argue the nature of H as the second sound in the hydrodynamic regime. We articulate, based on a diquark picture, how the structural change of the condensates and the associated NG bosons occurs continuously from hadronic to CFL quark matter if the quark-hadron continuity is realized. We sharpen the qualitative difference between the flavor octet pions and the singlet phason. We propose a conjecture that superfluid H matter undergoes a crossover to a superconductor with tightly-bound diquarks, and then a crossover to superconducting matter with diquarks dissociated. |
1705.07007 | Zijie Poh | Zijie Poh, Stuart Raby | Vector-like Leptons: Muon g-2 Anomaly, Lepton Flavor Violation, Higgs
Decays, and Lepton Non-Universality | 24 pages, 8 figures, 2 tables | Phys. Rev. D 96, 015032 (2017) | 10.1103/PhysRevD.96.015032 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we consider the Standard Model (SM) with one family of
vector-like (VL) leptons, which couple to all three families of the SM leptons.
We study the constraints on this model coming from the heavy charged lepton
mass bound, electroweak precision data, the muon anomalous magnetic moment,
lepton flavor violation, Higgs decay constraints and a recently measured lepton
non-universality observable, $R_{K^{*0}}$. We find that the strongest
constraints are coming from the muon $g-2, \
R_{\mu\mu}=\Gamma(h\to\mu\mu)/\Gamma(h\to\mu\mu)_\text{SM}, \ R_{\gamma\gamma}$
and $\text{BR}(\mu\to e\gamma)$. Although VL leptons couple to all three
families of the SM leptons, the ratio of electron-VL to muon-VL coupling is
constrained to be $\langle\lambda_e/\lambda_\mu\rangle\lesssim10^{-4}$. We also
find that our model cannot fit the observed value of $R_{K^{*0}}$.
| [
{
"created": "Fri, 19 May 2017 14:15:41 GMT",
"version": "v1"
}
] | 2017-08-02 | [
[
"Poh",
"Zijie",
""
],
[
"Raby",
"Stuart",
""
]
] | In this paper, we consider the Standard Model (SM) with one family of vector-like (VL) leptons, which couple to all three families of the SM leptons. We study the constraints on this model coming from the heavy charged lepton mass bound, electroweak precision data, the muon anomalous magnetic moment, lepton flavor violation, Higgs decay constraints and a recently measured lepton non-universality observable, $R_{K^{*0}}$. We find that the strongest constraints are coming from the muon $g-2, \ R_{\mu\mu}=\Gamma(h\to\mu\mu)/\Gamma(h\to\mu\mu)_\text{SM}, \ R_{\gamma\gamma}$ and $\text{BR}(\mu\to e\gamma)$. Although VL leptons couple to all three families of the SM leptons, the ratio of electron-VL to muon-VL coupling is constrained to be $\langle\lambda_e/\lambda_\mu\rangle\lesssim10^{-4}$. We also find that our model cannot fit the observed value of $R_{K^{*0}}$. |
1008.3550 | Fernando Navarra | E.R. Cazaroto, F. Carvalho, V.P. Goncalves, M.S. Kugeratski and F.S.
Navarra | Exclusive processes in electron - ion collisions | 6 pages, 4 figures | Phys.Lett.B696:473-477,2011 | 10.1016/j.physletb.2010.12.071 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The exclusive processes in electron-ion ($eA$) interactions are an important
tool to investigate the QCD dynamics at high energies as they are in general
driven by the gluon content of the target, which is strongly subject to parton
saturation effects. In this paper we compute the cross sections for the
exclusive vector meson production as well as the deeply virtual Compton
scattering (DVCS) relying on the color dipole approach and considering the
numerical solution of the Balitsky-Kovchegov equation including running
coupling corrections (rcBK). The production cross sections obtained with the
rcBK solution and bCGC parametrization are very similar, the former being
slightly larger.
| [
{
"created": "Fri, 20 Aug 2010 18:25:10 GMT",
"version": "v1"
}
] | 2011-03-07 | [
[
"Cazaroto",
"E. R.",
""
],
[
"Carvalho",
"F.",
""
],
[
"Goncalves",
"V. P.",
""
],
[
"Kugeratski",
"M. S.",
""
],
[
"Navarra",
"F. S.",
""
]
] | The exclusive processes in electron-ion ($eA$) interactions are an important tool to investigate the QCD dynamics at high energies as they are in general driven by the gluon content of the target, which is strongly subject to parton saturation effects. In this paper we compute the cross sections for the exclusive vector meson production as well as the deeply virtual Compton scattering (DVCS) relying on the color dipole approach and considering the numerical solution of the Balitsky-Kovchegov equation including running coupling corrections (rcBK). The production cross sections obtained with the rcBK solution and bCGC parametrization are very similar, the former being slightly larger. |
hep-ph/9811370 | Valera Lyubovitskij | M. A. Ivanov (JINR, Dubna), J. G. Korner (Mainz University), V. E.
Lyubovitskij (JINR, Dubna and Tomsk University) | One-Photon Transitions between Heavy Baryons in a Relativistic
Three-Quark Model | 13 pages, LaTeX-file, 1 Figure | Phys.Lett. B448 (1999) 143-151 | 10.1016/S0370-2693(99)00029-5 | Preprint Mainz Univ. MZ-TH/98-46 | hep-ph | null | We study one-photon transitions between heavy baryon states in the framework
of a relativistic three-quark model. We calculate the one-photon transition
rates for ground-state to ground-state transitions and for some specific
excited state to ground-state transitions. Our rate predictions for the most
important transitions are: $\Gamma(\Sigma^{+}_{c}\to \Lambda_c^+\gamma)=
60.7\pm 1.5 $ KeV, $\Gamma(\Xi^{'+}_{c}\to \Xi_c^+\gamma) = 12.7\pm 1.5$ KeV,
$\Gamma(\Lambda_{c1}(2593)\to\Lambda_c^+\gamma)=104.3\pm 1.3$ KeV.
| [
{
"created": "Tue, 17 Nov 1998 15:41:50 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Ivanov",
"M. A.",
"",
"JINR, Dubna"
],
[
"Korner",
"J. G.",
"",
"Mainz University"
],
[
"Lyubovitskij",
"V. E.",
"",
"JINR, Dubna and Tomsk University"
]
] | We study one-photon transitions between heavy baryon states in the framework of a relativistic three-quark model. We calculate the one-photon transition rates for ground-state to ground-state transitions and for some specific excited state to ground-state transitions. Our rate predictions for the most important transitions are: $\Gamma(\Sigma^{+}_{c}\to \Lambda_c^+\gamma)= 60.7\pm 1.5 $ KeV, $\Gamma(\Xi^{'+}_{c}\to \Xi_c^+\gamma) = 12.7\pm 1.5$ KeV, $\Gamma(\Lambda_{c1}(2593)\to\Lambda_c^+\gamma)=104.3\pm 1.3$ KeV. |
1410.7345 | Barry Dillon | Barry M. Dillon and Stephan J. Huber | Non-Custodial Warped Extra Dimensions at the LHC? | 24 pages, 4 figures; v2: Typo in eq.48 fixed, references added | JHEP 06 (2015) 066 | 10.1007/JHEP06(2015)066 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | With the prospect of improved Higgs measurements at the LHC and at proposed
future colliders such as ILC, CLIC and TLEP we study the non-custodial
Randall-Sundrum model with bulk SM fields and compare brane and bulk Higgs
scenarios. The latter bear resemblance to the well studied type III
two-Higgs-doublet models. We compute the electroweak precision observables and
argue that incalculable contributions to these, in the form of higher
dimensional operators, could have an impact on the T-parameter. This could
potentially reduce the bound on the lowest Kaluza-Klein gauge boson masses to
the 5 TeV range, making them detectable at the LHC. In a second part, we
compute the misalignment between fermion masses and Yukawa couplings caused by
vector-like Kaluza-Klein fermions in this setup. The misalignment of the top
Yukawa can easily reach 10%, making it observable at the high-luminosity LHC.
Corrections to the bottom and tau Yukawa couplings can be at the percent level
and detectable at ILC, CLIC or TLEP.
| [
{
"created": "Mon, 27 Oct 2014 18:36:26 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Dec 2014 14:34:04 GMT",
"version": "v2"
}
] | 2015-11-25 | [
[
"Dillon",
"Barry M.",
""
],
[
"Huber",
"Stephan J.",
""
]
] | With the prospect of improved Higgs measurements at the LHC and at proposed future colliders such as ILC, CLIC and TLEP we study the non-custodial Randall-Sundrum model with bulk SM fields and compare brane and bulk Higgs scenarios. The latter bear resemblance to the well studied type III two-Higgs-doublet models. We compute the electroweak precision observables and argue that incalculable contributions to these, in the form of higher dimensional operators, could have an impact on the T-parameter. This could potentially reduce the bound on the lowest Kaluza-Klein gauge boson masses to the 5 TeV range, making them detectable at the LHC. In a second part, we compute the misalignment between fermion masses and Yukawa couplings caused by vector-like Kaluza-Klein fermions in this setup. The misalignment of the top Yukawa can easily reach 10%, making it observable at the high-luminosity LHC. Corrections to the bottom and tau Yukawa couplings can be at the percent level and detectable at ILC, CLIC or TLEP. |
1608.01248 | Konstantin Zhukovsky | K.Zhukovsky, F.M.Murilio | Exponential parameterization of neutrino mixing matrix with account for
CP-violation data | null | European Physical Journal C 2016 | 10.1140/epjc/s10052-016-4310-7 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The exponential parameterization of Pontecorvo-Maki-Nakagawa-Sakata mixing
matrix for neutrino is discussed. The exponential form allows easy
factorization and separate analysis of the CP-violating and Majorana terms.
Based upon the recent experimental data on the neutrino mixing, the values for
the exponential parameterization matrix for neutrinos are determined. The
matrix entries for the pure rotational part in charge of the mixing without
CP-violation are derived. The complementarity hypothesis for quarks and
neutrinos is demonstrated. The comparison of the results, based on most recent
and on old data is held. The CP-violating parameter value is estimated, based
on the so far imprecise experimental indications, regarding CP-violation for
neutrinos. The unitarity of the exponential parameterisation and the
CP-violating term transform is confirmed. The transform of the neutrino mass
state vector by the exponential matrix with account for CP-violation is shown.
| [
{
"created": "Wed, 3 Aug 2016 16:34:17 GMT",
"version": "v1"
}
] | 2016-09-21 | [
[
"Zhukovsky",
"K.",
""
],
[
"Murilio",
"F. M.",
""
]
] | The exponential parameterization of Pontecorvo-Maki-Nakagawa-Sakata mixing matrix for neutrino is discussed. The exponential form allows easy factorization and separate analysis of the CP-violating and Majorana terms. Based upon the recent experimental data on the neutrino mixing, the values for the exponential parameterization matrix for neutrinos are determined. The matrix entries for the pure rotational part in charge of the mixing without CP-violation are derived. The complementarity hypothesis for quarks and neutrinos is demonstrated. The comparison of the results, based on most recent and on old data is held. The CP-violating parameter value is estimated, based on the so far imprecise experimental indications, regarding CP-violation for neutrinos. The unitarity of the exponential parameterisation and the CP-violating term transform is confirmed. The transform of the neutrino mass state vector by the exponential matrix with account for CP-violation is shown. |
1310.5843 | Ye-Ling Zhou | Ye-Ling Zhou | Majorana phases in neutrino-antineutrino oscillations | 4 pages, 4 figures, NUFACT 2013 proceedings | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | If the massive neutrinos are Majorana particles, neutrinoless double beta
($0\nu\beta\beta$) decay experiments are not enough to determine the Majorana
phases. We carry out a systematic study of CP violation in
neutrino-antineutrino oscillations. In these processes, CP-conserving parts
involve six independent $0\nu\beta\beta$-like mass terms $\langle
m\rangle_{\alpha\beta}$ and CP-violating parts are associated with nine
independent Jarlskog-like parameters ${\cal V}^{ij}_{\alpha\beta}$ (for
$\alpha, \beta = e, \mu, \tau$ and $i, j = 1, 2,3$). With the help of current
neutrino oscillation data, we illustrate the salient features of six
independent CP-violating asymmetries between $\nu_\alpha \to \bar{\nu}_\beta$
and $\bar{\nu}_\alpha \to \nu_\beta$ oscillations.
| [
{
"created": "Tue, 22 Oct 2013 09:00:15 GMT",
"version": "v1"
}
] | 2013-10-23 | [
[
"Zhou",
"Ye-Ling",
""
]
] | If the massive neutrinos are Majorana particles, neutrinoless double beta ($0\nu\beta\beta$) decay experiments are not enough to determine the Majorana phases. We carry out a systematic study of CP violation in neutrino-antineutrino oscillations. In these processes, CP-conserving parts involve six independent $0\nu\beta\beta$-like mass terms $\langle m\rangle_{\alpha\beta}$ and CP-violating parts are associated with nine independent Jarlskog-like parameters ${\cal V}^{ij}_{\alpha\beta}$ (for $\alpha, \beta = e, \mu, \tau$ and $i, j = 1, 2,3$). With the help of current neutrino oscillation data, we illustrate the salient features of six independent CP-violating asymmetries between $\nu_\alpha \to \bar{\nu}_\beta$ and $\bar{\nu}_\alpha \to \nu_\beta$ oscillations. |
1404.3558 | Ole Svendsen | A. Codello, J. Joergensen, F. Sannino, O. Svendsen | Marginally Deformed Starobinsky Gravity | 5 pages, 1 figure, 2 columns | JHEP 1502 (2015) 50 | 10.1007/JHEP02(2015)050 | CP3-Origins-2014-13 DNRF90, DIAS-2014-13 | hep-ph gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that quantum-induced marginal deformations of the Starobinsky
gravitational action of the form $R^{2(1 -\alpha)}$, with $R$ the Ricci scalar
and $\alpha$ a positive parameter, smaller than one half, can account for the
recent experimental observations by BICEP2 of primordial tensor modes. We also
suggest natural microscopic (non) gravitational sources of these corrections
and demonstrate that they lead generally to a nonzero and positive $\alpha$.
Furthermore we argue, that within this framework, the tensor modes probe
theories of grand unification with a large scalar field content.
| [
{
"created": "Mon, 14 Apr 2014 12:48:15 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Jan 2015 19:55:08 GMT",
"version": "v2"
},
{
"created": "Tue, 10 Feb 2015 19:04:33 GMT",
"version": "v3"
}
] | 2015-02-11 | [
[
"Codello",
"A.",
""
],
[
"Joergensen",
"J.",
""
],
[
"Sannino",
"F.",
""
],
[
"Svendsen",
"O.",
""
]
] | We show that quantum-induced marginal deformations of the Starobinsky gravitational action of the form $R^{2(1 -\alpha)}$, with $R$ the Ricci scalar and $\alpha$ a positive parameter, smaller than one half, can account for the recent experimental observations by BICEP2 of primordial tensor modes. We also suggest natural microscopic (non) gravitational sources of these corrections and demonstrate that they lead generally to a nonzero and positive $\alpha$. Furthermore we argue, that within this framework, the tensor modes probe theories of grand unification with a large scalar field content. |
1701.03064 | Mikhail Voloshin | M.B. Voloshin | Some properties of the states at the hidden-strangeness mixed ${1 \over
2}^+ + {1 \over 2}^-$ heavy meson pair threshold in $e^+e^-$ annihilation | 9 pages | Phys. Rev. D 95, 054017 (2017) | 10.1103/PhysRevD.95.054017 | FTPI-MINN-17/01, UMN-TH-3617/17 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The threshold behavior of $e^+ e^-$ annihilation is considered in the
channels $B_{s0} \bar B_s^* + c.c.$, $B_{s1} \bar B_s + c.c.$, and $B_{s1} \bar
B_s^* +c.c.$, where $B_{s0}$ and $B_{s1}$ are the excited bottom-strange
$J^P=0^+$ and $J^P = 1^+$ mesons. It is argued that due to the heavy quark spin
symmetry (HQSS) only one coherent combination of the first two channels is
produced in the $S$ wave as well as the third channel. Thus, if there exist
threshold molecular peaks in the considered channels, only two of such peaks
can be formed in the annihilation. The properties of such threshold states are
discussed, including the heavy-light spin structure and the related transitions
to bottomonium plus light mesons, as well as mixing with the channels with and
without hidden strangeness.
| [
{
"created": "Wed, 11 Jan 2017 17:10:35 GMT",
"version": "v1"
},
{
"created": "Mon, 16 Jan 2017 15:38:18 GMT",
"version": "v2"
}
] | 2017-03-29 | [
[
"Voloshin",
"M. B.",
""
]
] | The threshold behavior of $e^+ e^-$ annihilation is considered in the channels $B_{s0} \bar B_s^* + c.c.$, $B_{s1} \bar B_s + c.c.$, and $B_{s1} \bar B_s^* +c.c.$, where $B_{s0}$ and $B_{s1}$ are the excited bottom-strange $J^P=0^+$ and $J^P = 1^+$ mesons. It is argued that due to the heavy quark spin symmetry (HQSS) only one coherent combination of the first two channels is produced in the $S$ wave as well as the third channel. Thus, if there exist threshold molecular peaks in the considered channels, only two of such peaks can be formed in the annihilation. The properties of such threshold states are discussed, including the heavy-light spin structure and the related transitions to bottomonium plus light mesons, as well as mixing with the channels with and without hidden strangeness. |
2111.07789 | Timo K\"arkk\"ainen | Timo J. K\"arkk\"ainen, Zolt\'an Tr\'ocs\'anyi | Super-weakly coupled U(1)$_z$ and GeV neutrinos | 10 pages, 3 figures. Contribution to Matter To The Deepest: Recent
Developments In Physics Of Fundamental Interactions XLIV International
Conference of Theoretical Physics | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The $super$-$weak$ force combines three simple extensions of the Standard
Model, one in gauge sector, one in fermion sector and one in scalar sector.
Each of these extensions are well motivated by their rich phenomenology.
Combined to a single framework, they can explain several open questions in
particle physics and cosmology: the origin of dark matter, cosmic inflation,
matter-antimatter asymmetry, neutrino masses and vacuum stability. We discuss
the effects of the model on neutrino masses and phenomenology in the case where
the heaviest sterile neutrinos have a GeV scale mass.
| [
{
"created": "Mon, 15 Nov 2021 14:26:00 GMT",
"version": "v1"
}
] | 2021-11-16 | [
[
"Kärkkäinen",
"Timo J.",
""
],
[
"Trócsányi",
"Zoltán",
""
]
] | The $super$-$weak$ force combines three simple extensions of the Standard Model, one in gauge sector, one in fermion sector and one in scalar sector. Each of these extensions are well motivated by their rich phenomenology. Combined to a single framework, they can explain several open questions in particle physics and cosmology: the origin of dark matter, cosmic inflation, matter-antimatter asymmetry, neutrino masses and vacuum stability. We discuss the effects of the model on neutrino masses and phenomenology in the case where the heaviest sterile neutrinos have a GeV scale mass. |
hep-ph/0205231 | Carlos A. Salgado | K.J. Eskola, H. Honkanen, V.J. Kolhinen and C.A. Salgado | Constraints for nuclear gluon densities from DIS data | 4 pages, 3 postscript figures. Contributed to 37th Rencontres de
Moriond on QCD and Hadronic Interactions, Les Arcs, France, 16-23 Mar 2002 | null | null | null | hep-ph | null | The $Q^2$ dependence of the ratios of nuclear structure functions $F_2^A$ is
studied by performing QCD evolution of nuclear parton distribution functions.
The log $Q^2$ slope of these ratios is very sensitive to the nuclear gluon
distribution function. Taking different parametrizations, we show that the NMC
data on the $Q^2$ dependence of $F_2^{\rm Sn}/F_2^{\rm C}$ rule out the case
where nuclear shadowing (suppression) of gluons at $x\sim 0.01$ is much larger
than the shadowing observed in the ratio $F_2^A/F_2^{\rm D}$. We also take into
account modifications to the DGLAP evolution by including gluon fusion terms
and see that the effect is small at present energies, and, in any case, a
strong gluon shadowing is not favored. The region studied ($x \sim 0.01$) is
the most relevant for RHIC multiplicities.
| [
{
"created": "Tue, 21 May 2002 14:49:50 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Eskola",
"K. J.",
""
],
[
"Honkanen",
"H.",
""
],
[
"Kolhinen",
"V. J.",
""
],
[
"Salgado",
"C. A.",
""
]
] | The $Q^2$ dependence of the ratios of nuclear structure functions $F_2^A$ is studied by performing QCD evolution of nuclear parton distribution functions. The log $Q^2$ slope of these ratios is very sensitive to the nuclear gluon distribution function. Taking different parametrizations, we show that the NMC data on the $Q^2$ dependence of $F_2^{\rm Sn}/F_2^{\rm C}$ rule out the case where nuclear shadowing (suppression) of gluons at $x\sim 0.01$ is much larger than the shadowing observed in the ratio $F_2^A/F_2^{\rm D}$. We also take into account modifications to the DGLAP evolution by including gluon fusion terms and see that the effect is small at present energies, and, in any case, a strong gluon shadowing is not favored. The region studied ($x \sim 0.01$) is the most relevant for RHIC multiplicities. |
hep-ph/0511127 | Rafel Escribano | R. Escribano (UAB & IFAE, Barcelona) | Phenomenological test of the large N_c ChPT predictions for the
pseudoscalar mixing parameters | 7 pages, uses appolb style. Talk presented at the PHOTON2005
International Conference on the Structure and Interactions of the Photon,
Warsaw, Poland, 31.8-4.9.2005 | Acta Phys.Polon. B37 (2006) 867 | null | UAB-FT-591 | hep-ph | null | A phenomenological analysis of various decay processes is performed in order
to test the large $N_c$ Chiral Perturbation Theory predictions for the octet
and singlet pseudoscalar decay constants and mixing angles. The results
obtained hint at a disagreement with the expectations of this theoretical
framework although the statistical significance is still limited.
| [
{
"created": "Thu, 10 Nov 2005 11:28:13 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Escribano",
"R.",
"",
"UAB & IFAE, Barcelona"
]
] | A phenomenological analysis of various decay processes is performed in order to test the large $N_c$ Chiral Perturbation Theory predictions for the octet and singlet pseudoscalar decay constants and mixing angles. The results obtained hint at a disagreement with the expectations of this theoretical framework although the statistical significance is still limited. |
2212.04699 | Geng Li | Chao-Qiang Geng, Geng Li | FCNC processes of charmed hadrons with invisible scalar | 13 pages, 18 figures | null | 10.1016/j.physletb.2023.137811 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We study the invisible scalar of $S$ in charmed meson and baryon decays with
flavor-changing neutral currents (FCNCs) based on the model-independent
effective Lagrangian between the quarks and invisible scalar. From the bounds
of the coupling constants extracted from the recent BES III experiment on the
decay of $D^{0}\to\pi^{0}\bar\nu\nu$, we predict that the decay branching
ratios of $D^{+}\to\pi^{+}S$, $D_s^+\to K^+S$, $\Lambda_c\to pS$,
$\Xi_c^{0(+)}\to \Sigma^{0(+)}S$, and $\Xi_c^0\to\Lambda S$ can be as large as
$10.6,~2.53,~2.39,~0.963,~5.77$, and $2.92\times10^{-4}$ with $m_{_S}\approx
1.1~{\rm GeV}$, respectively. Some of these decay modes are accessible to the
ongoing experiments, such as BES III, LHCb and Belle II, as well as the future
ones, such as FCC-ee.
| [
{
"created": "Fri, 9 Dec 2022 07:24:55 GMT",
"version": "v1"
},
{
"created": "Sat, 4 Mar 2023 02:36:11 GMT",
"version": "v2"
}
] | 2023-03-07 | [
[
"Geng",
"Chao-Qiang",
""
],
[
"Li",
"Geng",
""
]
] | We study the invisible scalar of $S$ in charmed meson and baryon decays with flavor-changing neutral currents (FCNCs) based on the model-independent effective Lagrangian between the quarks and invisible scalar. From the bounds of the coupling constants extracted from the recent BES III experiment on the decay of $D^{0}\to\pi^{0}\bar\nu\nu$, we predict that the decay branching ratios of $D^{+}\to\pi^{+}S$, $D_s^+\to K^+S$, $\Lambda_c\to pS$, $\Xi_c^{0(+)}\to \Sigma^{0(+)}S$, and $\Xi_c^0\to\Lambda S$ can be as large as $10.6,~2.53,~2.39,~0.963,~5.77$, and $2.92\times10^{-4}$ with $m_{_S}\approx 1.1~{\rm GeV}$, respectively. Some of these decay modes are accessible to the ongoing experiments, such as BES III, LHCb and Belle II, as well as the future ones, such as FCC-ee. |
0807.4205 | Rafel Escribano | R. Escribano (UAB and IFAE, Barcelona) | Eta' gluonic content and J/psi->VP decays | 5 pages, uses espcrc2 style. Talk presented at the International
Workshop on e+e- collisions from Phi to Psi (PHIPSI08), Laboratori Nazionali
di Frascati (Rome), Italy, 7-10 April 2008 | Nucl.Phys.Proc.Suppl.181-182:226-230,2008 | 10.1016/j.nuclphysbps.2008.09.041 | UAB-FT-652 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The $\eta$-$\eta^\prime$ pseudoscalar mixing angle and the gluonium content
of the $\eta^\prime$ meson are deduced from an updated phenomenological
analysis of $J/\psi$ decays into a vector and a pseudoscalar meson. The values
for the mixing angle and the gluonic content of the $\eta^\prime$ wave function
are $\phi_P=(44.5\pm 4.3)^\circ$ and $Z^2_{\eta^\prime}=0.28\pm 0.21$,
respectively.
| [
{
"created": "Fri, 25 Jul 2008 23:58:48 GMT",
"version": "v1"
}
] | 2008-11-07 | [
[
"Escribano",
"R.",
"",
"UAB and IFAE, Barcelona"
]
] | The $\eta$-$\eta^\prime$ pseudoscalar mixing angle and the gluonium content of the $\eta^\prime$ meson are deduced from an updated phenomenological analysis of $J/\psi$ decays into a vector and a pseudoscalar meson. The values for the mixing angle and the gluonic content of the $\eta^\prime$ wave function are $\phi_P=(44.5\pm 4.3)^\circ$ and $Z^2_{\eta^\prime}=0.28\pm 0.21$, respectively. |
hep-ph/0205272 | Matthias Burkardt | Matthias Burkardt, Xiangdong Ji, and Feng Yuan (University of
Maryland) | Scale Dependence of Hadronic Wave Functions and Parton Densities | 9 pages, references added | Phys.Lett.B545:345-351,2002 | 10.1016/S0370-2693(02)02596-0 | null | hep-ph | null | We study how the components of hadronic wave functions in light-cone
quantization depend on the ultraviolet cut-off by relating them in a systematic
way to the matrix elements of a class of quark-gluon operators between the QCD
vacuum and the hadrons. From this, we derive an infinite set of scale-evolution
equations for the individual contributions to parton distributions from the
Fock expansion. When summed over all the contributions, we recover the
well-known DGLAP equation.
| [
{
"created": "Thu, 23 May 2002 23:36:10 GMT",
"version": "v1"
},
{
"created": "Tue, 28 May 2002 16:21:59 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Burkardt",
"Matthias",
"",
"University of\n Maryland"
],
[
"Ji",
"Xiangdong",
"",
"University of\n Maryland"
],
[
"Yuan",
"Feng",
"",
"University of\n Maryland"
]
] | We study how the components of hadronic wave functions in light-cone quantization depend on the ultraviolet cut-off by relating them in a systematic way to the matrix elements of a class of quark-gluon operators between the QCD vacuum and the hadrons. From this, we derive an infinite set of scale-evolution equations for the individual contributions to parton distributions from the Fock expansion. When summed over all the contributions, we recover the well-known DGLAP equation. |
hep-ph/0004044 | Heribert Weigert | Heribert Weigert (Nordita) | Unitarity at small Bjorken x | 28 pages, several diagrams. Typos corrected, minor useful changes in
notation | Nucl.Phys. A703 (2002) 823-860 | 10.1016/S0375-9474(01)01668-2 | NORDITA-2000/34 HE | hep-ph | null | This paper presents a solution to the nonlinear small x ``projectile side''
evolution equations as derived by Balitskii in 1996. The solution is based on
functional Fokker-Planck methods. The fixed point at small x is explicitly
calculated and all correlation functions in this limit are determined. They
show clear saturation and unitarization properties. Scaling laws that hold
during the saturation phase and throughout the whole course of the evolution
are established. The corresponding Langevin equations are given as a basis for
numerical simulations opening the field for future studies of dynamical issues
of the evolution not analytically accessible. The methods used may be extended
to the ``target side'' equations of Jalilian-Marian, Kovner, Leonidov and
Weigert.
| [
{
"created": "Wed, 5 Apr 2000 23:20:25 GMT",
"version": "v1"
},
{
"created": "Tue, 23 May 2000 12:05:10 GMT",
"version": "v2"
},
{
"created": "Tue, 27 Nov 2001 13:32:07 GMT",
"version": "v3"
}
] | 2009-10-31 | [
[
"Weigert",
"Heribert",
"",
"Nordita"
]
] | This paper presents a solution to the nonlinear small x ``projectile side'' evolution equations as derived by Balitskii in 1996. The solution is based on functional Fokker-Planck methods. The fixed point at small x is explicitly calculated and all correlation functions in this limit are determined. They show clear saturation and unitarization properties. Scaling laws that hold during the saturation phase and throughout the whole course of the evolution are established. The corresponding Langevin equations are given as a basis for numerical simulations opening the field for future studies of dynamical issues of the evolution not analytically accessible. The methods used may be extended to the ``target side'' equations of Jalilian-Marian, Kovner, Leonidov and Weigert. |
hep-ph/0107295 | Kornelija Passek | Blazenka Melic, Bene Nizic, Kornelija Passek | BLM scale for the pion transition form factor | 35 pages, 11 figures; revised: (v2) minor changes in the text; (v3)
only some typos corrected | Phys.Rev. D65 (2002) 053020 | 10.1103/PhysRevD.65.053020 | IRB-TH-13/00 | hep-ph | null | The NLO Brodsky-Lepage-Mackenzie (BLM) scale for the pion transition form
factor has been determined. To achieve that, a consistent calculation up to
nf-proportional NNLO contributions to both the hard-scattering amplitude and
the perturbatively calculable part of the pion distribution amplitude has been
performed. By combining and matching the results obtained for these two
amplitudes, a proper cancellation of collinear singularities has been
established and the gamma5 ambiguity problem (related to the use of the
dimensional regularization method) has been resolved by using the naive-gamma5
as well as the 't Hooft-Veltman (HV) schemes. It has been demonstrated that the
prediction for the pion transition form factor is independent of the
factorization scale muF at every order in the strong coupling constant, making
it possible to use the simplest choice muF^2=Q^2 at the intermediate steps of
the calculation. Assuming the pion asymptotic distribution amplitude and
working in the \bar{MS} scheme, we have found the BLM scale to be muR^2=muBLM^2
~ Q^2/9. Based on the same distribution, the complete NLO prediction for the
pion transition form factor has been calculated in the alphaV definition of the
QCD coupling renormalized at muR^2=muV^2 = e^{5/3} muBLM^2 ~ Q^2/2. It is in
good agreement with the presently available experimental data.
| [
{
"created": "Mon, 30 Jul 2001 00:50:30 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Oct 2001 18:30:13 GMT",
"version": "v2"
},
{
"created": "Tue, 26 Feb 2002 20:18:55 GMT",
"version": "v3"
}
] | 2009-11-07 | [
[
"Melic",
"Blazenka",
""
],
[
"Nizic",
"Bene",
""
],
[
"Passek",
"Kornelija",
""
]
] | The NLO Brodsky-Lepage-Mackenzie (BLM) scale for the pion transition form factor has been determined. To achieve that, a consistent calculation up to nf-proportional NNLO contributions to both the hard-scattering amplitude and the perturbatively calculable part of the pion distribution amplitude has been performed. By combining and matching the results obtained for these two amplitudes, a proper cancellation of collinear singularities has been established and the gamma5 ambiguity problem (related to the use of the dimensional regularization method) has been resolved by using the naive-gamma5 as well as the 't Hooft-Veltman (HV) schemes. It has been demonstrated that the prediction for the pion transition form factor is independent of the factorization scale muF at every order in the strong coupling constant, making it possible to use the simplest choice muF^2=Q^2 at the intermediate steps of the calculation. Assuming the pion asymptotic distribution amplitude and working in the \bar{MS} scheme, we have found the BLM scale to be muR^2=muBLM^2 ~ Q^2/9. Based on the same distribution, the complete NLO prediction for the pion transition form factor has been calculated in the alphaV definition of the QCD coupling renormalized at muR^2=muV^2 = e^{5/3} muBLM^2 ~ Q^2/2. It is in good agreement with the presently available experimental data. |
1409.1301 | Andrey Kozhushko | Alexey Gulov, Andrey Kozhushko | Two-parametric observables for Abelian $Z'$ searching in $p\bar{p}$
collisions at Tevatron energies | Added references and some supplemental info. Corrected "Z-Z'
interference" to "Z-Z' mixing". Will be further updated and extended before
for publishing. 12 pages, 6 figures, the paper is essentially rewritten
arXiv:1209.5022 with many shortcomings corrected | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a scheme of searches for the Abelian $Z'$ gauge boson in the
Drell-Yan process at $\sqrt{S}=1.96$ TeV. We base our considerations on
renor\-ma\-li\-za\-tion-group relations between the $Z'$ couplings to
standard-model fermions. Considering the range of energies near the $Z$-boson
peak, namely $66-116$ GeV for the invariant mass of a leptonic pair, we propose
an integration scheme to construct two-parametric observables suitable for $Z'$
searches in the $p\bar{p} \to l^+ l^-$ scattering. The observables allow to
constrain the $Z'$ vector and axial-vector couplings to SM fermions in a
general phenomenological parameterization with non-universal $Z'$ interactions
with fermion generations. We also consider the cases of generation-universal
$Z'$ boson and leptophobic $Z'$ boson, and show that one-parametric observables
exist for these scenarios. The research is aimed to supplement direct searches
for $Z'$ as an on-shell state in a specific set of new-physics models.
| [
{
"created": "Thu, 4 Sep 2014 02:24:07 GMT",
"version": "v1"
},
{
"created": "Sat, 28 Mar 2015 10:41:15 GMT",
"version": "v2"
},
{
"created": "Sun, 31 Jan 2016 14:18:13 GMT",
"version": "v3"
}
] | 2016-02-02 | [
[
"Gulov",
"Alexey",
""
],
[
"Kozhushko",
"Andrey",
""
]
] | We propose a scheme of searches for the Abelian $Z'$ gauge boson in the Drell-Yan process at $\sqrt{S}=1.96$ TeV. We base our considerations on renor\-ma\-li\-za\-tion-group relations between the $Z'$ couplings to standard-model fermions. Considering the range of energies near the $Z$-boson peak, namely $66-116$ GeV for the invariant mass of a leptonic pair, we propose an integration scheme to construct two-parametric observables suitable for $Z'$ searches in the $p\bar{p} \to l^+ l^-$ scattering. The observables allow to constrain the $Z'$ vector and axial-vector couplings to SM fermions in a general phenomenological parameterization with non-universal $Z'$ interactions with fermion generations. We also consider the cases of generation-universal $Z'$ boson and leptophobic $Z'$ boson, and show that one-parametric observables exist for these scenarios. The research is aimed to supplement direct searches for $Z'$ as an on-shell state in a specific set of new-physics models. |
hep-ph/0303166 | Peter Schweitzer | P.Schweitzer, M.Colli (Pavia U.), S. Boffi (Pavia U. & INFN, Pavia) | Polynomiality of helicity off-forward distribution functions in the
chiral quark-soliton model | 10 pages, latex, no figures | Phys.Rev. D67 (2003) 114022 | 10.1103/PhysRevD.67.114022 | null | hep-ph | null | The polynomiality condition -- i.e. the property that Mellin moments of
off-forward distribution functions are even polynomials in the skewedness
parameter -- is a demanding check of consistency for model approaches. We
demonstrate that the helicity off-forward distribution functions in the chiral
quark-soliton model satisfy the polynomiality property. The proof contributes
to the demonstration that the description of off-forward distribution functions
in the model is consistent.
| [
{
"created": "Wed, 19 Mar 2003 16:35:20 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Schweitzer",
"P.",
"",
"Pavia U."
],
[
"Colli",
"M.",
"",
"Pavia U."
],
[
"Boffi",
"S.",
"",
"Pavia U. & INFN, Pavia"
]
] | The polynomiality condition -- i.e. the property that Mellin moments of off-forward distribution functions are even polynomials in the skewedness parameter -- is a demanding check of consistency for model approaches. We demonstrate that the helicity off-forward distribution functions in the chiral quark-soliton model satisfy the polynomiality property. The proof contributes to the demonstration that the description of off-forward distribution functions in the model is consistent. |
hep-ph/0409015 | Dmitri Melikhov | Dmitri Melikhov and Berthold Stech | Pentaquarks in the Chiral Symmetry Limit | Modified version. We added a discussion of the effect of spontaneous
breaking of chiral symmetry on the pentaquark. This has changed part of our
conclusions: we argue that the effect is large indicating that chiral
symmetry cannot be the origin of the small width of the pentaquark | Phys.Lett. B608 (2005) 59-63 | 10.1016/j.physletb.2005.01.014 | null | hep-ph | null | We demonstrate that a five quark state of positive parity with an internal
P-wave structure - usually pictured as a composite of an antiquark and two
diquarks in a P-wave state - can couple to nucleons and Goldstone particles in
a chirally invariant way. The corresponding decay width is generally not
suppressed. A pentaquark of positive or negative parity with an internal S-wave
structure, which may be viewed as a composite of an antiquark and two chirally
different diquarks in an S-state, does not couple to nucleons and light mesons
in the limit of an unbroken chiral symmetry. It is stable in this limit.
However, such states can decay via the effect of the spontaneous breaking of
chiral symmetry. This breaking is strong because of the sizeable magnitude of
the quark condensate. Thus, chiral symmetry cannot be the cause of a tiny decay
amplitude, even for pentaquarks stable in a strict chiral symmetry limit.
| [
{
"created": "Thu, 2 Sep 2004 11:23:48 GMT",
"version": "v1"
},
{
"created": "Wed, 8 Dec 2004 17:22:12 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Melikhov",
"Dmitri",
""
],
[
"Stech",
"Berthold",
""
]
] | We demonstrate that a five quark state of positive parity with an internal P-wave structure - usually pictured as a composite of an antiquark and two diquarks in a P-wave state - can couple to nucleons and Goldstone particles in a chirally invariant way. The corresponding decay width is generally not suppressed. A pentaquark of positive or negative parity with an internal S-wave structure, which may be viewed as a composite of an antiquark and two chirally different diquarks in an S-state, does not couple to nucleons and light mesons in the limit of an unbroken chiral symmetry. It is stable in this limit. However, such states can decay via the effect of the spontaneous breaking of chiral symmetry. This breaking is strong because of the sizeable magnitude of the quark condensate. Thus, chiral symmetry cannot be the cause of a tiny decay amplitude, even for pentaquarks stable in a strict chiral symmetry limit. |
1705.04468 | Juan Rojo | Juan Rojo | Improving quark flavor separation with forward W and Z production at
LHCb | 5 pages, 5 figures, to appear in the proceedings of the XXV
International Workshop on Deep-Inelastic Scattering and Related Subjects, 3-7
April 2017, University of Birmingham, UK | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We quantify the constraints on the flavour separation between the quarks and
antiquarks in the proton provided by the recent forward weak gauge boson
production data from the LHCb experiment at $\sqrt{s}=7$ and 8 TeV. Performed
in the framework of the NNPDF3.1 global analysis, this study highlights the key
role that the LHCb W and Z data have in achieving a robust quark flavour
separation in the large-x region, including the strange and charm quarks. We
demonstrate how the LHCb measurements lead to improved determinations of the
the up and down quark PDFs in the region $x\ge 0.1$, with an uncertainty
reduction that can be as large as a factor 2. We also show how the LHCb forward
measurements severely restrict the size of the fitted charm PDF at large x,
imposing stringent constraints on non-perturbative models for the charm content
of the nucleon.
| [
{
"created": "Fri, 12 May 2017 08:29:47 GMT",
"version": "v1"
}
] | 2017-05-15 | [
[
"Rojo",
"Juan",
""
]
] | We quantify the constraints on the flavour separation between the quarks and antiquarks in the proton provided by the recent forward weak gauge boson production data from the LHCb experiment at $\sqrt{s}=7$ and 8 TeV. Performed in the framework of the NNPDF3.1 global analysis, this study highlights the key role that the LHCb W and Z data have in achieving a robust quark flavour separation in the large-x region, including the strange and charm quarks. We demonstrate how the LHCb measurements lead to improved determinations of the the up and down quark PDFs in the region $x\ge 0.1$, with an uncertainty reduction that can be as large as a factor 2. We also show how the LHCb forward measurements severely restrict the size of the fitted charm PDF at large x, imposing stringent constraints on non-perturbative models for the charm content of the nucleon. |
hep-ph/9802352 | Thomas Gajdosik | A. Bartl, E. Christova, T. Gajdosik, W. Majerotto | CP violating angular asymmetries of b and bbar quarks in e+e- -> t tbar | 22 pages LaTeX with 3x3 figures included; some definitions for
polarization asymmetries and some notations are changed and some references
added | Phys. Rev. D 58, 074007 (1998) | 10.1103/PhysRevD.58.074007 | HEPHY--PUB 684, INRNE--TH--98/12, UWThPh--1998--2 | hep-ph | null | We obtain analytical formulae for the cross section and the angular
distributions of the b(bbar) quarks in the process e+e- -> t tbar, with t -> W+
b (tbar -> W- bbar) assuming CP violation in the \gamma t tbar and Z t tbar
vertices. We present CP violating asymmetries, which measure separately the
real and imaginary parts of the electroweak dipole moment form factors of the
top, d^{\gamma}(s) and d^{Z}(s). We give a numerical analysis of these
asymmetries within the Minimal Supersymmetric Standard Model with complex
parameters. They turn out to be of order <= 10^{-3}.
| [
{
"created": "Wed, 18 Feb 1998 16:53:51 GMT",
"version": "v1"
},
{
"created": "Thu, 12 Mar 1998 17:25:49 GMT",
"version": "v2"
}
] | 2016-08-25 | [
[
"Bartl",
"A.",
""
],
[
"Christova",
"E.",
""
],
[
"Gajdosik",
"T.",
""
],
[
"Majerotto",
"W.",
""
]
] | We obtain analytical formulae for the cross section and the angular distributions of the b(bbar) quarks in the process e+e- -> t tbar, with t -> W+ b (tbar -> W- bbar) assuming CP violation in the \gamma t tbar and Z t tbar vertices. We present CP violating asymmetries, which measure separately the real and imaginary parts of the electroweak dipole moment form factors of the top, d^{\gamma}(s) and d^{Z}(s). We give a numerical analysis of these asymmetries within the Minimal Supersymmetric Standard Model with complex parameters. They turn out to be of order <= 10^{-3}. |
1709.07895 | Doyoun Kim | Peter Athron, Csaba Balazs, Benjamin Farmer, Andrew Fowlie, Dylan
Harries and Doyoun Kim | Bayesian analysis and naturalness of (Next-to-)Minimal Supersymmetric
Models | 52 pages, 11 figures and 3 tables, Published in JHEP | JHEP10(2017)160 | 10.1007/JHEP10(2017)160 | CTPU-17-33, CoEPP-MN-17-18 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Higgs boson discovery stirred interest in next-to-minimal supersymmetric
models, due to the apparent fine-tuning required to accommodate it in minimal
theories. To assess their naturalness, we compare fine-tuning in a
$\mathbb{Z}_3$ conserving semi-constrained Next-to-Minimal Supersymmetric
Standard Model (NMSSM) to the constrained MSSM (CMSSM). We contrast popular
fine-tuning measures with naturalness priors, which automatically appear in
statistical measures of the plausibility that a given model reproduces the weak
scale. Our comparison shows that naturalness priors provide valuable insight
into the hierarchy problem and rigorously ground naturalness in Bayesian
statistics. For the CMSSM and semi-constrained NMSSM we demonstrate qualitative
agreement between naturalness priors and popular fine tuning measures. Thus, we
give a clear plausibility argument that favours relatively light superpartners.
| [
{
"created": "Fri, 22 Sep 2017 18:10:01 GMT",
"version": "v1"
},
{
"created": "Thu, 9 Nov 2017 07:21:11 GMT",
"version": "v2"
}
] | 2017-11-10 | [
[
"Athron",
"Peter",
""
],
[
"Balazs",
"Csaba",
""
],
[
"Farmer",
"Benjamin",
""
],
[
"Fowlie",
"Andrew",
""
],
[
"Harries",
"Dylan",
""
],
[
"Kim",
"Doyoun",
""
]
] | The Higgs boson discovery stirred interest in next-to-minimal supersymmetric models, due to the apparent fine-tuning required to accommodate it in minimal theories. To assess their naturalness, we compare fine-tuning in a $\mathbb{Z}_3$ conserving semi-constrained Next-to-Minimal Supersymmetric Standard Model (NMSSM) to the constrained MSSM (CMSSM). We contrast popular fine-tuning measures with naturalness priors, which automatically appear in statistical measures of the plausibility that a given model reproduces the weak scale. Our comparison shows that naturalness priors provide valuable insight into the hierarchy problem and rigorously ground naturalness in Bayesian statistics. For the CMSSM and semi-constrained NMSSM we demonstrate qualitative agreement between naturalness priors and popular fine tuning measures. Thus, we give a clear plausibility argument that favours relatively light superpartners. |
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