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hep-ph/9302241
Medley in finite temperature field theory
I discuss three subjects in thermal field theory: why in \sun gauge theories the \zn symmetry is broken at high (instead of low) temperature, the possible singularity structure of gauge variant propagators, and the problem of how to compute the viscosity from the Kubo formula.
1993-02-09
2015-06-25
[ "hep-ph" ]
R. D. Pisarski
hep-ph/9302240
The renormalization of the axial anomaly in dimensional regularization
The prescription for the $\gamma_5$-matrix within dimensional regularization in multiloop calculations is elaborated. The three-loop anomalous dimension of the singlet axial current is calculated.
1993-02-09
2014-11-17
[ "hep-ph" ]
S.A. Larin
hep-ph/9302232
Polarized $q\to\Lambda$ Fragmentation Functions from $e^+e^-\to\Lambda+X^*$
Measurement of the helicity asymmetric cross section for semi-inclusive production of $\Lambda$-hyperons in $e^+e^-$ annihilation near the $Z^0$ resonance allows a complete determination of the spin-dependent fragmentation functions for the different quark flavors into the $\Lambda$. The parity violating, self analyzin...
1993-02-08
2009-10-22
[ "hep-ph" ]
M. Burkardt and R. L. Jaffe
hep-ph/9302235
Complementarity and Chiral Fermions in SU(2) gauge Theories
Complementarity - the absence of a phase boundary separating the Higgs and confinement phases of a gauge theory - can be violated by the addition of chiral fermions. We utilize chiral symmetry violating fermion correlators such as $ \langle \bps \psi \rangle $ as order parameters to investigate this issue. Using inequa...
1993-02-08
2009-10-22
[ "hep-ph", "hep-lat" ]
Stephen D.H. Hsu
hep-ph/9302234
Improved LEP lower bound on the lightest SUSY Higgs mass from Radiative Electroweak Breaking and its Experimental Consequences
We show that the present LEPI lower bound on the Standard Model Higgs boson mass ($M_H\gsim60\GeV$) applies as well to the lightest Higgs boson ($h$) of the minimal $SU(5)$ and no-scale flipped $SU(5)$ supergravity models. This result would persist even for the ultimate LEPI lower bound ($M_H\gsim70\GeV$). We show that...
1993-02-08
2009-08-25
[ "hep-ph" ]
J. Lopez, D. Nanopoulos, H. Pois, X. Wang, and A. Zichichi
hep-ph/9302231
QCD Sum Rule and Perturbative QCD Approaches to Pion Compton Scattering
We compare two approaches to the description of pion Compton scattering at moderate momentum transfer, one being based on local duality QCD sum rules for the invariant amplitudes of the process, which have been derived recently, and the other on the modified factorization formula with Sudakov effects included. We find ...
1993-02-08
2010-11-01
[ "hep-ph" ]
Claudio Coriano' and Hsiang-nan Li
hep-ph/9302230
CP violation in Higgs decays
We study CP violation in fermion pair decays of Higgs boson. We idenfy some CP odd observables related to the tree level decay amplitude. We find that a few thousand Higgs boson decay events can already provide important information about CP violation. If the Higgs boson is produced, such an analysis could be carried o...
1993-02-08
2010-11-01
[ "hep-ph" ]
Xiao-Gang He, J.P. Ma and Bruce McKellar
hep-ph/9302233
Partition function for the eigenvalues of the Wilson line
In a gauge theory at nonzero temperature the eigenvalues of the Wilson line form a set of gauge invariant observables. By constructing the corresponding partition function for the phases of these eigenvalues, we prove that the trivial vacuum, where the phases vanish, is a minimum of the free energy.
1993-02-08
2009-10-22
[ "hep-ph", "hep-lat" ]
A. Gocksch and R. D. Pisarski
hep-ph/9302229
Neutrino masses from discrete gauge symmetries
We investigate a model with an extra $Z_{2}$ gauge symmetry in the Standard Model. We assume that only the scalars and the leptons carry non-zero charge. The symmetry gives a structure to the mass matrix for the neutrinos. With two extra Higgs singlets and two extra singlet right-handed neutrinos we can build a model t...
1993-02-06
2009-10-22
[ "hep-ph" ]
Jihn E. Kim and B-A Lindholm
hep-ph/9302228
Z\rightarrow A^0 A^0\nu\bar\nu$ and $e^+e^-\rightarrow A^0 A^0 Z$ in Two Higgs Doublet Models
In LEP searches for the neutral CP-odd scalar $A^0$ of a multi-Higgs doublet model, experimenters have searched for $Z\rightarrow h^0 A^0$ (where $h^0$ is the lightest CP-even scalar). No model-independent limit on the $A^0$ mass can be deduced from present data if $m_{h^0}>m_Z$. In this paper, we compute the rates for...
1993-02-06
2009-10-22
[ "hep-ph" ]
Howard E. Haber and Yosef Nir
hep-ph/9302226
Inelastic Channels in WW Scattering
If the electroweak symmetry-breaking sector becomes strongly interacting at high energies, it can be probed through longitudinal $W$ scattering. We present a model with many inelastic channels in the $W_L W_L$ scattering process, corresponding to the production of heavy fermion pairs. These heavy fermions affect the el...
1993-02-05
2008-11-26
[ "hep-ph" ]
S. G. Naculich and C.-P. Yuan
hep-ph/9302225
Higher Order Corrections to Jet Cross Sections in Hadron Colliders
We describe a general method of calculating the fully differential cross section for the production of jets at next-to-leading order in a hadron collider. This method is based on a `crossing' of next-to-leading order calculations with all partons in the final state. The method introduces universal crossing functions th...
1993-02-05
2008-11-26
[ "hep-ph" ]
Walter T. Giele, E. W. Nigel Glover, David A. Kosower
hep-ph/9302223
Inflation, Neutrino Baryogenesis, and (S)Neutrino-Induced Baryogenesis
We evaluate the constraints that the COBE observations put on baryogenesis in inflationary cosmologies.We consider the supersymmetric version of the proposal of Fukugita and Yanagida, that the baryon asymmetry of the universe is created by nonperturbative electroweak reprocessing of a lepton asymmetry generated in the ...
1993-02-05
2009-09-15
[ "hep-ph" ]
B.A. Campbell, S. Davidson, and K.A. Olive
hep-ph/9302227
A Natural Solution to the MU Problem
We propose a simple mechanism for solving the $\mu$ problem in the context of minimal low--energy supergravity models. This is based on the appearance of non--renormalizable couplings in the superpotential. In particular, if $H_1H_2$ is an allowed operator by all the symmetries of the theory, it is natural to promote t...
1993-02-05
2008-11-26
[ "hep-ph" ]
J.A. Casas and C. Munoz
hep-ph/9302221
On the Baryon, Lepton-Flavour and Right-Handed Electron Asymmetries of the Universe
Non-perturbative electroweak effects, in thermal equilibrium in the early universe, have the potential to erase the baryon asymmetry of the universe, unless it is encoded in a B-L asymmetry, or in some "accidentally" conserved quantity. We first consider the possibility that the BAU may be regenerated from lepton flavo...
1993-02-05
2009-09-11
[ "hep-ph" ]
B.A. Campbell, S. Davidson, J. Ellis, And K.A. Olive
hep-ph/9302220
Vortex Solutions in Two-Higgs Systems and $\tan\beta$
Classical vortex solutions in various two-Higgs systems are studied. The systems we consider include the standard model with two Higgs doublets, in which case the vortex appears as part of a string-like object. The Higgs potentials contain several different couplings in general and the spontaneous symmetry breaking inv...
1993-02-05
2008-02-03
[ "hep-ph", "hep-th" ]
HoSeong La
hep-ph/9302222
Supersymmetric (S)Neutrino-Mass Induced Baryogenesis
We propose a new mechanism for baryogenesis in supersymmetric extensions of the standard model, that does not depend on (super)GUT interactions. It occurs by the non-perturbative electroweak reprocessing of a lepton asymmetry. This lepton asymmetry is generated by the effects of lepton number violating induced operator...
1993-02-05
2009-09-15
[ "hep-ph" ]
B.A. Campbell, S. Davidson, and K.A. Olive
hep-ph/9302224
Radiative Corrections to the Neutral Higgs Spectrum in Supersymmetry with a Gauge Singlet
The radiative corrections to the $3\times3$scalar and the $2\times2$ pseudoscalar neutral Higgs boson massmatrices are calculated in the supersymmetric extension of the standard model including a gauge singlet superfield in the effective potential approach. The full $t$ and $b$ quark/squark contributions including the ...
1993-02-05
2009-10-22
[ "hep-ph" ]
Ulrich Ellwanger
hep-ph/9302218
One Loop Corrections To The Lightest Higgs Mass In The Minimal $\eta $ Model
We have evaluated the one loop correction to the bound on the lightest Higgs mass valid in the minimal, $ E_{6}$ based, supersymmetric $ \eta$ model. Under the assumption that the theory remains perturbative up to the $10^{16}$ GeV scale, we derive a conservative bound that decreases with the top mass for $M_t \leq 2 M...
1993-02-04
2009-10-22
[ "hep-ph" ]
D.Comelli and C.Verzegnassi (Dept. of Theorical Physics, University of Trieste and INFN sez.di Trieste)
hep-ph/9302217
Violations of Dashen's Theorem
The electromagnetic contribution to the $K^+ - K^0$ mass difference is calculated in the $1/N_c$ approach including the $SU(3)$ breaking contributions due to a non-zero strange quark mass. The short-distance contribution can be unambiguously determined in terms of the known parameters of the next-to-leading order chira...
1993-02-04
2009-10-22
[ "hep-ph" ]
J. Bijnens
hep-ph/9302216
Production of two hard isolated photons in $e^+e^-\to\mu^+\mu^-\gamma\gamma$ at LEP
A calculation of the hard bremsstrahlung process e+ e- -> mu+ mu- gamma gamma is presented and compared with recent results from the L3 Collaboration.
1993-02-04
2009-10-22
[ "hep-ph" ]
K. Ko{\l}odziej, F. Jegerlehner and G. J. van Oldenborgh
hep-ph/9302215
The Breaking of the SU(3)^3 Gauge Group
We discuss why the SU(3)^3 supersymmetric model with the most general superpotential can naturally break to the standard model if gauge singlets and a discrete symmetry are included. This mechanism does away with the need for fine-tuning in the form of the assumed absence of certain terms in the superpotential. It also...
1993-02-04
2007-05-23
[ "hep-ph" ]
Meng Y. Wang and Eric D. Carlson
hep-ph/9302219
Semileptonic $\pi$ and $K$ Decays and the Chiral Anomaly at One-loop
We calculate the $O(p^6)$ corrections to the anomalous form factors appearing in $\pi^+$, $K^+ \to e^+ \nu \gamma,\ \mu^+\nu\gamma$ and $K_{l4}$ decays in Chiral Perturbation Theory. The relevant dimension $6$ terms of the lagrangian are evaluated assuming their saturation by the vector meson contribution.
1993-02-04
2009-10-22
[ "hep-ph" ]
Ll. Ametller, J. Bijnens, A. Bramon and F. Cornet
hep-ph/9302211
Small-Size Instanton Corrections to the $\tau$ Hadronic Width
We compute the effect of small-size instanton corrections to current-current correlators, for all combinations of axial, vector, and possibly flavour non-diagonal currents. We apply our result to the hadronic decays of the $\tau$ lepton, in order to assess the reliability of the determination of $\as$ from the $\tau$ h...
1993-02-03
2009-10-22
[ "hep-ph" ]
P. Nason and M. Porrati
hep-ph/9302206
Searching for T,CP,CPT,and \Delta S = \Delta Q rule violations in the neutral K meson system - a guide
It is known that the existing experimental limit for$ CPT $ violation is rather poor; the 10 \% level at best. The $ \DSDQ $ rule is tested only up to 2 \%. In this note, we discuss the possibility of measuring $ T, CP, CPT $ and $ \DSDQ $ rule violations in the neutral $ K $ meson system. It is shown that not all the ...
1993-02-03
2008-11-26
[ "hep-ph" ]
M.Hayakawa and A.I.Sanda
hep-ph/9302209
Long Distance Contributions to B-Decays into Higher K-Resonances
We use the new symmetries in the heavy quark limit to calculate the exclusive B-decays $B \rightarrow K^i \psi $ where $K^i$ are higher resonances of K-meson. We then estimate the long distance contributions to $B \rightarrow K^i \gamma $ decays via $\psi - \gamma$ conversion. The results point to around $30 \%$ uncert...
1993-02-03
2007-05-23
[ "hep-ph" ]
Mohammad R. Ahmady, Dongsheng Liu and Zhijian Tao
hep-ph/9302207
Spontaneous CP Violation in the Minimal Supersymmetric Standard Model at Finite Temperature
We show that in the Minimal Supersymmetric Standard Model one--loop effects at finite temperature may lead to a spontaneous breaking of CP invariance in the scalar sector. Requiring that the breaking takes place at the critical temperature for the electroweak phase transition, we find that the parameters space is compa...
1993-02-03
2010-11-01
[ "hep-ph" ]
D. Comelli and M. Pietroni
hep-ph/9302208
The three-loop QCD $\beta$-function and anomalous dimensions
The analytic calculation of the three-loop QCD $\beta$-function and anomalous dimensions within the minimal subtraction scheme in an arbitrary covariant guage is presented. The result for the $\beta$-function coincides with the previous calculation \cite{tvz}.
1993-02-03
2011-05-05
[ "hep-ph" ]
S.A. Larin and J.A.M. Vermaseren
hep-ph/9302212
Cosmological Consequences of Spontaneous Lepton Number Violation in $SO(10)$ Grand Unification, EFI-93-07
Cosmological constraints on grand unified theories with spontaneous lepton number violation are analysed. We concentrate on $SO(10)$, the simplest of the models possessing this property. It has been noted previously that the consistency of these models with the observed baryon asymmetry generically implies strict upper...
1993-02-03
2009-10-22
[ "hep-ph" ]
Tony Gherghetta and Gerard Jungman
hep-ph/9302214
E2/M1 Mixing Ratio of $\Delta\to N\gamma$ and Hyperon Resonance Radiative Decay
We compute the leading contribution to the E2/M1 mixing ratio of the decay $\Delta\rightarrow N\gamma$ in heavy baryon chiral perturbation theory. We find the mixing ratio to be $4\% \ltap |\delta_{\rm E2/M1}| \ltap 11\%$, much larger than estimates based on the quark model and other hadronic models. We also compute th...
1993-02-03
2009-10-22
[ "hep-ph", "nucl-th" ]
M.N. Butler, M.J. Savage, and R.P. Springer
hep-ph/9302213
Neutrino Energy Loss from the Plasma Process at all Temperatures and Densities
We present a unified approach which is accurate at all temperatures and densities for calculating the energy loss from a stellar plasma due to the plasma process, the decay of photons and plasmons into neutrino pairs. To allow efficient numerical calculations, an analytic approximation to the dispersion equations for p...
1993-02-03
2009-12-30
[ "hep-ph" ]
Eric Braaten and Daniel Segel
hep-ph/9302210
Progress in Electroweak Baryogenesis
Recent work on generating the excess of matter over antimatter in the early universe during the electroweak phase transition is reviewed.
1993-02-03
2009-10-22
[ "hep-ph" ]
A. G. Cohen, D. B. Kaplan, A. E. Nelson
hep-ph/9302204
Physics at B-Factories
The main motivation for B factories is the investigation of CP violation. We consider two questions: 1) Why has there been essentially no experimental progress in CP violation in the 28 years since its discovery in 1964? 2) Why do we expect better results from B factories?
1993-02-02
2007-05-23
[ "hep-ph" ]
Harry. J. Lipkin
hep-ph/9302205
The Electroweak Phase Transition in Minimal Supergravity Models
We have explored the electroweak phase transition in minimal supergravity models by extending previous analysis of the one-loop Higgs potential to include finite temperature effects. Minimal supergravity is characterized by two higgs doublets at the electroweak scale, gauge coupling unification, and universal soft-SUSY...
1993-02-02
2011-04-20
[ "hep-ph" ]
D. V. Nanopoulos and H. Pois
hep-ph/9302203
Photon-Photon Scattering, Pion Polarizability and Chiral Symmetry
Recent attempts to detect the pion polarizability via analysis of $\gamma\gamma\rightarrow\pi\pi$ measurements are examined. The connection between calculations based on dispersion relations and on chiral perturbation theory is established by matching the low energy chiral amplitude with that given by a full dispersive...
1993-02-02
2011-07-19
[ "hep-ph", "nucl-th" ]
John F. Donoghue and Barry R. Holstein
hep-ph/9302202
Supersymmetric Higgs Bosons at the Limit
We obtain an improved upper bound on the lightest neutral CP-even Higgs boson mass from a low energy renormalisation-group analysis of the Higgs sector of the next-to-minimal supersymmetric standard model. We find $m_h< 145$ GeV for $m_t=90$ GeV, decreasing to $m_h< 123$ GeV for $m_t=180$ GeV. We also discuss the light...
1993-02-02
2009-10-22
[ "hep-ph" ]
T.Elliott, S.F.King and P.L.White
hep-ph/9301296
Probes of parton transversity
An inventory is made of the experiments which can measure the transversely polarized quark distributions and fragmentation functions at leading twist. (Contribution to the 10th International Symposium on High Energy Spin Physics, Nagoya, Japan, Nov. 9-14, 1992)
1993-02-01
2008-02-03
[ "hep-ph" ]
X. Artru
hep-ph/9301295
Chiral Dynamics and Heavy-Fermion Formalism in Nuclei: I. Exchange Axial Currents
Chiral perturbation theory in heavy-fermion formalism is developed for meson-exchange currents in nuclei and applied to nuclear axial- charge transitions. Calculation is performed to the next-to-leading order in chiral expansion which involves graphs up to one loop. The result turns out to be very simple. The previousl...
1993-02-01
2010-04-06
[ "hep-ph", "nucl-th" ]
Tae-Sun Park, Dong-Pil Min and Mannque Rho
hep-ph/9302201
Neutrinoless double beta decay in an $SU(3)_L\otimes U(1)_N$ model
We consider a model for the electroweak interactions with $SU(3)_L\otimes U(1)_N$ gauge symmetry. We show that, it is the conservation of $F=L+B$ which forbids massive neutrinos and the neutrinoless double beta decay, $(\beta\beta)_{0\nu}$. Explicit and spontaneous breaking of $F$ imply that the neutrinos have an arbit...
1993-02-01
2009-10-22
[ "hep-ph" ]
V. Pleitez and M.D. Tonasse
hep-ph/9301294
A More-Effective Potential
In theories with spontaneous symmetry breaking, the loop expansion of the effective potential is awkward. In such theories, the exact effective potential $V(\phi_c,T)$ is real and convex (as a function of the classical field $\phi_c$), but its perturbative series can be complex with a real part that is concave. These f...
1993-02-01
2009-10-22
[ "hep-ph" ]
Kevin Cahill
hep-ph/9301293
The Electric Dipole Moment of the W and Electron in the Standard Model
I show that the electric dipole moment of the W-boson vanishes to two loop order in the Standard KM model. As a consequence, the electric dipole moment of the electron vanishes to three loop order. Including QCD corrections may give a non-vanishing result; I estimate d_W \approx 8 10^-31 ecm which induces an electron E...
1993-01-30
2009-09-25
[ "hep-ph" ]
Michael Booth
hep-ph/9301292
Indications for a Detonating Quark-Gluon Plasma
We propose a mechanism which naturally contains the relation $\mu_{B} = 3\mu_{S}$ of the hadronic gas produced in heavy-ion collisions at CERN. Our starting assumption is the existence of a sharp front separating the quark-gluon plasma phase from the hadronic phase. Energy-momentum conservation across the front leads t...
1993-01-29
2010-11-01
[ "hep-ph" ]
N. Bili\'c, J. Cleymans, E. Suhonen, D.W. von Oertzen
hep-ph/9301290
Leptonic Flavor-changing Z0 Decays in SU(2)xU(1) Theories with Right- handed Neutrinos
We analyze possible lepton-flavor-violating decays of the $Z^0$ particle in a minimal extension of the Standard Model, in which one right-handed neutral field for each family has been introduced. Such rare leptonic decays are induced by Majorana neutrinos at the first electroweak loop level and are generally not suppre...
1993-01-28
2009-10-22
[ "hep-ph" ]
J.G. Koerner, A. Pilaftsis, K. Schilcher
hep-ph/9301289
Leptonic CP Asymmetries in Flavor-changing H0 Decays
Leptonic flavor-changing $H^0$ decays with branching ratios of the order of $10^{-5}-10^{-6}$ may constitute an interesting framework when looking for large $CP$-violating effects. We show that leptonic $CP$~asymmetries of an intermediate $H^0$ boson can be fairly large in natural scenarios of the minimal Standard Mode...
1993-01-28
2010-11-01
[ "hep-ph" ]
J. G. Koerner, A. Pilaftsis, K. Schilcher
hep-ph/9301291
Neutrino Masses in Flipped SU(5)
We analyse the fermion masses and mixings in the flipped SU(5) model. The fermion mass matrices are evolved from the GUT scale down to $m_W$ by solving the renormalization group equations for the Yukawa couplings. The constraints imposed by the charged fermion data are then utilised to make predictions about the neutri...
1993-01-28
2010-11-01
[ "hep-ph" ]
G.K. Leontaris, and J.D. Vergados
hep-ph/9301285
The electroweak phase transition with a singlet
We study the electroweak phase transition in the minimal extension of the Standard Model: an extra complex singlet with zero vacuum expectation value. The first-order phase transition is strengthened by the cubic term triggered in the one-loop effective potential by the extra boson. Plasma effects are considered to lea...
1993-01-27
2009-10-22
[ "hep-ph" ]
J.R. Espinosa and M. Quir\'os
hep-ph/9301282
Interference Effects in B-Decays to Flavor-Mixed Neutral Mesons - Clues to Small Amplitudes and CP-Violation
CP violation can be observed in B decays when a given process depends upon interference between two weak amplitudes which have different $CP$-violating phases. Since most weak decay diagrams have quark lines where each has a definite flavor label, neutral mesons which are flavor mixtures are particularly interesting. D...
1993-01-27
2007-05-23
[ "hep-ph" ]
Harry. J. Lipkin
hep-ph/9301286
Restrictions on B-L Symmetry Breaking Implied by a Fourth Generation Neutrino
Several misprints in the earlier version (hep-ph/9301286) have been corrected.
1993-01-27
2009-10-22
[ "hep-ph" ]
R.N. Mohapatra and X. Zhang
hep-ph/9301288
$WZ$, $W\gamma$, $WW$ and $ZZ$ pair productions at TeV $e\gamma$ colliders
We calculate the gauge-boson pairs $W^-Z$, $W^-\gamma$, $W^+W^-$, $ZZ$ productions in the $e^- \gamma$ collisions, where the photon beam is realized by the laser back-scattering method. These processes are important tests for the non-abelian gauge sector of the standard model (SM). Precise calculations of these process...
1993-01-27
2009-10-22
[ "hep-ph" ]
Kingman Cheung
hep-ph/9301283
Dominant Three-Body Decays of a Heavy Higgs and Top Quark
We calculate the dominant three body Higgs decays, $H \to W^+W^-(Z^0, \gamma)$ and $H \to t\overline{t}(Z^0,\gamma ,g)$, in the Standard Model. We find that the branching ratios of these decays are of the order of few percent for large Higgs masses. We comment on the behaviour of the partial decay width $\Gamma (H \to ...
1993-01-27
2009-10-22
[ "hep-ph" ]
R. Decker, M. Nowakowski and A. Pilaftsis
hep-ph/9301284
Pair creation in transport equations using the equal-time Wigner function
Based on the equal-time Wigner function for the Klein-Gordon field, we discuss analytically the mechanism of pair creation in a classical electromagnetic field including back-reaction. It is shown that the equations of motion for the Wigner function can be reduced to a variable-frequency oscillator. The pair-creation r...
1993-01-27
2016-09-01
[ "hep-ph" ]
C. Best and J. M. Eisenberg
hep-ph/9301287
Family Symmetry, Fermion Mass Matrices and Cosmic Texture
The observed replication of fermions in three families is undoubtedly a reflection of a deeper symmetry underlying the standard model. In this paper we investigate one very elementary possibility, that physics above the grand unification scale is described by the symmetry group $G\timesSU(3)_{fam}$ with $G$ a gauged gr...
1993-01-27
2009-10-22
[ "hep-ph" ]
Michael Joyce and Neil Turok
hep-ph/9301281
The Chiral Approach to the Electroweak Interactions
The effective lagrangian approach is reviewed and applied to the case of electroweak interactions.
1993-01-27
2011-04-15
[ "hep-ph" ]
Ferruccio Feruglio
hep-ph/9301279
Nonleptonic Decays of Charmed Mesons into two Pseudoscalar Mesons
We investigate the nonleptonic decay of charmed meson into two pseudoscalar mesons using the vector--dominance model, and compare the results with those obtained from the factorization model. In particular, we discuss the role of the annihilation diagrams in the two models.
1993-01-26
2015-06-25
[ "hep-ph" ]
Ashok Das and Vishnu Mathur
hep-ph/9301278
The Rare Decay $B\to K^{\ast}\gamma$: A More Precise Calculation
Efforts to predict the rare exclusive decay $B\to K^{\ast}\gamma$ from the well known inclusive decay $b\to s\gamma$ are frustrated by the effect of the large recoil momentum. We show how to reduce the large uncertainty in calculating this decay by relating $B\to K^{\ast}\gamma$ to the semileptonic process $B\to\rho e\...
1993-01-26
2009-10-22
[ "hep-ph" ]
Patrick J. O'Donnell and Humphrey K.K. Tung
hep-ph/9301274
QCD Sum Rules and Compton Scattering
We extend QCD sum rule analysis to moderate energy fixed angle Compton scattering. In this kinematic region there is a strong similarity to the sum rule treatment of electromagnetic form factors, although the four-point amplitude requires a modification of the Borel transform. To illustrate our method, we derive the su...
1993-01-26
2014-11-17
[ "hep-ph" ]
Claudio Coriano', Anatoly Radyushkin and George Sterman
hep-ph/9301273
CP-odd Neutral Higgs Effects in Top -- anti-Top Production
We study $CP$ violation in the process $e^+e^- \to t\bar{t} \nu\bar{\nu}$ at an $e^+e^-$-TeV collider. As the source of $CP$ violation we assume a two-Higgs doublet model with an explicitly $CP$-noninvariant Higgs potential. Sizeable $CP$-odd observables originating from the subprocess reaction, $W^+W^- \to t\bar{t}$, ...
1993-01-26
2010-11-01
[ "hep-ph" ]
A. Pilaftsis and M. Nowakowski
hep-ph/9301272
CP-Violation with Bosons
We formulate the conditions under which a purely bosonic theory (without fermions) containing neutral spin-0 particles and vector (gauge) bosons violates the CP-symmetry through the presence of CP-even and CP-odd operators in the Lagrangian. This is done without reference to explicitly CP-violating scalar sector of ext...
1993-01-26
2010-11-01
[ "hep-ph" ]
G. Cvetic, M. Nowakowski and A. Pilaftsis
hep-ph/9301277
Operator Analysis for the Higgs Potential and Cosmological Bound on the Higgs-Boson Mass
Using effective lagrangian, we examine the impacts of new physics on the electroweak baryogenesis. By analysing the high dimensional operators relevent to the Higgs potential we point out that the Higgs mass bound required by electroweak baryogenesis can be relaxed to the region allowed by experiments, provided that ne...
1993-01-26
2009-10-22
[ "hep-ph" ]
X. Zhang
hep-ph/9301275
The phase-space structure of the Klein-Gordon field
The formalism based on the equal-time Wigner function of the two-point correlation function for a quantized Klein--Gordon field is presented. The notion of the gauge-invariant Wigner transform is introduced and equations for the corresponding phase-space calculus are formulated. The equations of motion governing the Wi...
1993-01-26
2009-10-22
[ "hep-ph" ]
C. Best, P. Gornicki, and W. Greiner
hep-ph/9301270
Application of M\"ossbauer-Type Sum Rules for $B$ Meson Decays
Sum rules originally derived for the M\"ossbauer Effect are applied to weak semileptonic B decays. The sum rules follow from assuming that the decay by electroweak boson emission of an unstable nucleus or heavy quark in a bound system is described by a pointlike coupling to a current which acts only on the decaying obj...
1993-01-26
2009-10-22
[ "hep-ph" ]
Harry J. Lipkin
hep-ph/9301269
Soft Modes Contribution into Path Integral
A method for nonperturbative path integral calculation is proposed. Quantum mechanics as a simplest example of a quantum field theory is considered. All modes are decomposed into hard (with frequencies $\omega^2 >\omega^2_0$) and soft (with frequencies $\omega^2 <\omega^2_0$) ones, $\omega_0$ is a some parameter. Har...
1993-01-26
2014-11-17
[ "hep-ph" ]
V.M.Belyaev
hep-ph/9301271
The Large N Limit and the High Temperature Phase Transition for the \phi^4 Theory
We study, with various methods (standard large N evaluation of the functional integral for the effective potential, solution of the Schwinger-Dyson equations), the high temperature phase transition for the $N$-component $\phi^4$ theory in the large $N$ limit. Our results fully confirm a previous investigation of the pr...
1993-01-26
2009-10-22
[ "hep-ph" ]
M. Reuter, N. Tetradis and C. Wetterich
hep-ph/9301280
Breaking Of Conformal Invariance And Electromagnetic Field Generation In The Universe
It is shown that the breaking of the conformal invariance in quantum electrodynamics due to the trace anomaly results in the generation of long wave electromagnetic fields during inflationary stage of the universe evolution. If the coefficient of the logarithmic charge renormalization is large (due to a large number of...
1993-01-26
2008-11-26
[ "hep-ph" ]
A. Dolgov Randall (Physics Laboratory University of Michigan, Ann Arbor, MI U.S.A. and ITEP, Moscow, Russia)
hep-ph/9301276
A global fit of $\pi\pi$ and $\pi K$ elastic scattering in ChPT with dispersion relations
We apply the one-loop results of the $SU(3)_L\times SU(3)_R$ ChPT suplemented with the inverse amplitude method to fit the available experimental data on $\pi\pi$ and $\pi K$ scattering. With esentially only three parameters we describe accurately data corresponding to six different channels, namely $(I,J)=(0,0), (2,0)...
1993-01-26
2009-10-22
[ "hep-ph" ]
A. Dobado and J. R. Pelaez
hep-ph/9301266
Fermion Density Induced Instability of the W-Boson Pair Condensate in Strong Magnetic Field
The electroweak vacuum structure in an external magnetic field close to the lower critical value is considered at finite fermion density. It is shown that the leading effect of the fermions is to reduce the symmetry of the W-pair condensate in the direction of the magnetic field. The energy is minimized by the appearan...
1993-01-25
2009-10-22
[ "hep-ph" ]
Erich R. Poppitz
hep-ph/9301267
Implications for Minimal Supersymmetry from Grand Unification and the Neutralino Relic Abundance
We examine various predictions of the minimal supersymmetric standard model coupled to minimal supergravity. The model is characterised by a small set of parameters at the unification scale. The supersymmetric particle spectrum at low energy and the spontaneous breaking of the standard model itself are then generated r...
1993-01-25
2009-10-22
[ "hep-ph" ]
R.G. Roberts and L. Roszkowski
hep-ph/9301265
CP Violation in the Decay of Neutral Higgs Boson into $t-{\bar t}$ or $W^+-W^-$
We investigate a potentially large CP violating asymmetry in the neutral Higgs boson decay into a heavy quark pair or a $W^+$--$W^-$ pair. The source of the CP nonconservation is in the Yukawa couplings of the Higgs boson which can contain both scalar and pseudoscalar pieces. One of the interesting consequence is the d...
1993-01-25
2009-09-01
[ "hep-ph" ]
D. Chang and W.-Y. Keung
hep-ph/9301268
Gauge Coupling Unification in Superstring Derived Standard--like Models
I discuss gauge coupling unification in a class of superstring standard--like models, which are derived in the free fermionic formulation. Recent calculations indicate that the superstring unification scale is at $O(10^{18}GeV)$ while the minimal supersymmetric standard model is consistent with LEP data if the unificat...
1993-01-25
2009-10-22
[ "hep-ph", "hep-th" ]
Alon E. Faraggi
hep-ph/9301261
Cabibbo Mixing in Superstring Derived Standard--like Models
We examine the problem of generation mixing in realistic superstring derived standard--like models, constructed in the free fermionic formulation. We study the possible sources of family mixing in these models . In a specific model we estimate the Cabibbo angle. We argue that a Cabibbo angle of the correct order of mag...
1993-01-22
2009-10-22
[ "hep-ph", "hep-th" ]
Alon E. Faraggi and Edi Halyo
hep-ph/9301259
CP Violation in top pair production at an e^+e^- collider
We investigate possible CP violating effects in $e^+e^-$ annihilation into top quark pairs. One of the interesting observable effects is the difference in production rates between the two CP conjugate polarized states $t_L\bar t_L$ and $t_R\bar t_R$. The result is an asymmetry in the energy spectra of the lepton and th...
1993-01-22
2009-09-01
[ "hep-ph" ]
Darwin Chang, Wai-Yee Keung, and Ivan Phillips
hep-ph/9301260
Gravitational Laser Back-Scattering
A possible way of producing gravitons in the laboratory is investigated. We evaluate the cross section electron + photon $\rightarrow$ electron + graviton in the framework of linearized gravitation, and analyse this reaction considering the photon coming either from a laser beam or from a Compton back-scattering proces...
1993-01-22
2009-10-22
[ "hep-ph" ]
S. F. Novaes and D. Spehler
hep-ph/9301264
Rare K-Decays as Crucial Tests for Unified Models with Gauged Baryon Number:
In the grand-unified models based on SU(15) and SU(16) in which the quarks and leptons are un-unified at the intermediate stages, we show that ${\rm BR}\; (K_L \to \mu e) \leq 10^{-14}$ and ${\rm BR}\; (K^+ \to \pi^+\mu e) \leq 10^{-14}$ despite the presence of leptoquark gauge bosons. Thus, the observation of these pr...
1993-01-22
2009-10-22
[ "hep-ph" ]
Palash B. Pal
hep-ph/9301263
High-Energy Cosmic-Ray Muons Under Thick Layers of Matter I. a Method to Solve the Transport Equation
An effective analytical method for calculating energy spectra of cosmic-ray muons at large depths of homogeneous media is developed. The method allows to include an arbitrary (decreasing) muon spectrum at the medium boundary and the energy dependence of both discrete (radiative and photonuclear) and continuous (ionizat...
1993-01-22
2007-05-23
[ "hep-ph" ]
V. A. Naumov, S. I. Sinegovsky, and E. V. Bugaev
hep-ph/9301262
Nuclear Gluon Distributions in a Parton Model
Gluon distributions in the carbon and tin nuclei are investigated by using a $Q^2$ rescaling model with parton recombination effects. We obtain strong shadowings in the small $x$ region due to the recombinations. The ratio $G_A(x)/G_N(x)$ in the medium $x$ region is typically 0.9 for medium size nuclei. At large $x$, t...
1993-01-22
2009-10-22
[ "hep-ph", "nucl-th" ]
S. Kumano (Indiana U., present address: U. of Mainz)
hep-ph/9301256
Chiral Dynamics and Fermion Mass Generation in Three Dimensional Gauge Theory
We examine the possibility of fermion mass generation in 2+1- dimensional gauge theory from the current algebra point of view.In our approach the critical behavior is governed by the fluctuations of pions which are the Goldstone bosons for chiral symmetry breaking. Our analysis supports the existence of an upper critic...
1993-01-21
2009-10-22
[ "hep-ph", "hep-th" ]
M.C.Diamantini G.W.Semenoff P.Sodano
hep-ph/9301258
Third Generation Effects on Fermion Mass Predictions in Supersymmetric Grand Unified Theories
Relations among fermion masses and mixing angles at the scale of grand unification are modified at lower energies by renormalization group running induced by gauge and Yukawa couplings. In supersymmetric theories, the $b$ quark and $\tau$ lepton Yukawa couplings, as well as the $t$ quark coupling, may cause significant...
1993-01-21
2009-10-22
[ "hep-ph" ]
Stephen G. Naculich
hep-ph/9301254
Next to leading order determination of pion fragmentation functions
We perform a complete next to leading order evaluation of inclusive neutral pion production from hadronic colliders which is based on the knowledge of the pion fragmentation functions at next to leading order. This problem has been tackled for the first time using different approaches. Predictions at LHC are given with...
1993-01-21
2008-11-26
[ "hep-ph" ]
P.Chiappetta, M.Greco, J.Ph.Guillet, S.Rolli, M.Werlen
hep-ph/9301255
Calculation of processes involving many particles at the kinematical threshold
A diagrammatic technique is derived for calculating processes involving the production of large numbers of particles. As an example, the amplitude of three particles scattering into $n$ particles at the kinematical threshold in $\lambda\phi^4$ theory is calculated. From the $3 \to n$ amplitude, it is seen that the one-...
1993-01-21
2007-05-23
[ "hep-ph" ]
Brian Hendee Smith
hep-ph/9301257
Delta-Isobar Magnetic Form Factor in QCD
We consider the QCD sum rules approach for Delta-isobar magnetic form factor in the infra-red region $0<Q^2<1GeV^2$. The QCD sum rules in external variable field are used. The obtained formfactor is in agreement with quark model predictions for the Delta-isobar magnetic moment.
1993-01-21
2007-05-23
[ "hep-ph" ]
V.M.Belyaev
hep-ph/9301253
Scalar Mesons in $\phi$ Radiative Decay: their implications for spectroscopy and for studies of CP-violation at $\phi$ factories
Existing predictions for the branching ratio for $\phi\rightarrow K\bar{K}\gamma$ {\it via} $\phi\rightarrow S\gamma$ (where $S$ denotes one of the scalar mesons $f_0$(975) and $a_0$(980)) vary by several orders of magnitude. Given the importance of these processes for both hadron spectroscopy and CP-violation studies ...
1993-01-21
2008-11-26
[ "hep-ph", "nucl-th" ]
F. E. Close (Rutherford), Nathan Isgur (CEBAF), and S. Kumano (Indiana --> Mainz)
hep-ph/9301252
Detection of the heavy Higgs boson at $\gamma\gamma$ colliders
We consider the possibility of detecting a heavy Higgs boson ($m_H>2m_Z$) in proposed $\gamma\gamma$ colliders through the semi-leptonic mode $\gamma\gamma \rightarrow H \rightarrow ZZ \rightarrow q\bar q \ell^+\ell^-$. We show that due to the non-monochromatic nature of the photon beams produced by the laser-backscatt...
1993-01-20
2009-10-22
[ "hep-ph" ]
David Bowser-Chao and Kingman Cheung
hep-ph/9301251
The $\eta_6$ at LEP and TRISTAN
The $\eta_6$ is a ``heavy axion'' remnant of dynamical electroweak symmetry breaking by a color sextet quark condensate. Electroweak scale color instanton interactions allow it to be both very massive and yet be responsible for Strong CP conservation in the color triplet quark sector. It may have been seen at LEP via i...
1993-01-20
2014-11-17
[ "hep-ph" ]
Alan R. White, Ian G. Knowles and Kyungsik Kang
hep-ph/9301250
Casimir forces between beads on strings
We consider a string with uniform energy density and tension and with a number of pointlike masses attached at fixed interdistances. We evaluate the effective interaction forces between these masses induced by the quantum fluctuations of the string. For interdistances large compared to the thickness of the string and s...
1993-01-19
2009-10-22
[ "hep-ph", "hep-lat", "hep-th" ]
Eric D'Hoker and Pierre Sikivie
hep-ph/9301249
Is Upsilon(3S) a pure S-wave?
Assuming the QCD multipole expansion is applicable to hadronic transitions of Upsilon(3S) into lower level bottomonia, we consider the possibility that Upsilon(3S) has a D-wave component. This assumption leads to a natural explanation of the pi-pi spectrum in Upsilon(3S) -> Upsilon(1S) pi-pi. Consequences of this assum...
1993-01-19
2011-01-27
[ "hep-ph" ]
Sumantra Chakravarty, Sun Myong Kim and Pyungwon Ko
hep-ph/9301248
Fermion Masses in SO(10)
Yukawa coupling constant unification together with the known fermion masses is used to constrain SO(10) models. We consider the case of one (heavy) generation, with the tree-level relation $m_b=m_\tau$, calculating the limits on the intermediate symmetry breaking scales. This analysis extends previous analyses which ad...
1993-01-19
2007-05-23
[ "hep-ph" ]
Gerard Jungman
hep-ph/9301247
Pontecorvo's Original Oscillations Revisited
We show that a left-handed neutrino $\nu_L$ can oscillate into its $CP$- conjugated state $\bar{\nu}_R$ with maximal amplitude, in direct analogy with $K^0-\bar{K}^0$ oscillations. Peculiarities of such oscillations under different conditions are studied.
1993-01-18
2008-11-26
[ "hep-ph" ]
E.Kh. Akhmedov, S.T. Petcov and A.Yu. Smirnov
hep-ph/9301246
Quark Models and Quark Phenomenology
Overwhelming experimental evidence for quarks as real physical constituents of hadrons along with the QCD analogs of the Balmer Formula, Bohr Atom and Schroedinger Equation already existed in 1966. A model of colored quarks interacting with a one-gluon-exchange potential explained the systematics of the meson and baryo...
1993-01-18
2007-05-23
[ "hep-ph" ]
Harry J. Lipkin
hep-ph/9301245
Symmetry Remnants: Rationale for Having Two Higgs Doublets
There is a good reason why the standard electroweak SU(2) X U(1) gauge model may be supplemented by two Higgs scalar doublets. They may be remnants of the spontaneous breaking of an SU(2) X SU(2) X U(1) gauge symmetry at a much higher energy scale. In one case, the two-doublet Higgs potential has a custodial SU(2) symm...
1993-01-16
2009-10-22
[ "hep-ph" ]
Ernest Ma and Daniel Ng
hep-ph/9301244
What $\pi-\pi$ Scattering Tells Us About Chiral Perturbation Theory
We describe a rearrangement of the standard expansion of the symmetry breaking part of the QCD effective Lagrangian that includes into each order additional terms which in the standard chiral perturbation theory ($\chi$PT) are relegated to higher orders. The new expansion represents a systematic and unambiguous general...
1993-01-16
2009-10-22
[ "hep-ph" ]
J. Stern, H. Sazdjian and N.H. Fuchs
hep-ph/9301241
Study of the Reactions $B \to D^* \pi \pi$ and $B \to D^* \rho \pi$
We evaluate the non leptonic decays $B \to D^* \pi \pi$ and $B \to D^* \rho \pi$ in the limit of infinitely heavy quarks, assuming the dominance of intermediate positive parity charmed resonances. We find that the branching ratios are of the order $10^(-3)$.
1993-01-15
2009-10-22
[ "hep-ph" ]
P.Colangelo, F.De Fazio and G.Nardulli
hep-ph/9301243
Implications of Solar and Atmospheric Neutrinos
The implications of the deficit of solar neutrinos are discussed. If all of the experiments are taken literally the relative suppressions render an astrophysical explanation unlikely. Allowing MSW conversions, the data simultaneously determine the temperature of the core of the sun to within five percent. The implicati...
1993-01-15
2007-05-23
[ "hep-ph" ]
Paul Langacker
hep-ph/9301240
Gravity and Domain Wall Problem
It is well known that the spontaneous breaking of discrete symmetries may lead to conflict with big-bang cosmology. This is due to formation of domain walls which give unacceptable contribution to the energy density of the universe. On the other hand it is expected that gravity breaks global symmetries explicitly. In t...
1993-01-15
2009-12-30
[ "hep-ph" ]
Balram Rai and Goran Senjanovic
hep-ph/9301242
Nonabelian Berry Phases in Baryons
We show how generic nonabelian gauge fields can be induced in baryons when a hierarchy of fast degrees of freedom is integrated out. We identify them with nonabelian Berry potentials and discuss their role in transmuting quantum numbers in bag and soliton models of baryons. The resulting baryonic spectra for both light...
1993-01-15
2009-10-22
[ "hep-ph", "nucl-th" ]
H.K. Lee, M.A. Nowak, Mannque Rho and I. Zahed
hep-ph/9301238
W + gamma + jet production as a test of the electromagnetic couplings of W at LHC and SSC
The reaction $pp \to W \ +\ \gamma\ +\ jet \ +\ X$ is considered at centre-of-mass energies $\sqrt{s} = 16$ and $40\;\tev$, including anomalous three-gauge-boson couplings $\kappa$ and $\lambda$. The possibility of obtaining limits on these quantities by comparison with the standard model is investigated. The radiation...
1993-01-14
2009-10-22
[ "hep-ph" ]
F.K. Diakonos, O. Korakianitis, C.G. Papadopoulos, C. Philippides and W.J. Stirling
hep-ph/9301239
Implications of Gallium Solar Neutrino Data for the Resonant Spin-Flavor Precession Scenario
We consider the implications of the recent results of SAGE and GALLEX experiments for the solution of the solar neutrino problem in the framework of the resonant neutrino spin-flavor precession scenario. It is shown that this scenario is consistent with all the existing solar neutrino data including the gallium results...
1993-01-14
2008-11-26
[ "hep-ph", "astro-ph" ]
E.Kh. Akhmedov, A. Lanza, S.T. Petcov
hep-ph/9301235
The Singlet Majoron Model with Hidden Scale Invariance
We investigate an extension of the Singlet Majoron Model in which the breaking of dilatation symmetry by the mass parameters of the scalar potential is removed by means of a dilaton field. Starting from the one-loop renormalization group improved potential, we discuss the ground state of the theory. The flat direction ...
1993-01-13
2009-10-22
[ "hep-ph" ]
Antonio Riotto
hep-ph/9301237
QCD corrections to the charged Higgs decay of a heavy quark
We present an analytic formula for the $O(\alpha_s)$ corrections to the decay $t\to H^+b$ for nonzero $m_H$ and $m_b$. The Equivalence Theorem is used to relate these corrections to those for the process $t\to W^+b$. Contrary to previously published results we find that the effect of the $b$ quark mass is negligible fo...
1993-01-13
2009-10-22
[ "hep-ph" ]
Andrzej Czarnecki and Sacha Davidson
hep-ph/9301236
Kinetic Equations for Longwavelength Excitations of the Quark-Gluon Plasma
We show that longwavelength excitations of the quark-gluon plasma are described by simple kinetic equations which represent the exact equations of motion at leading order in $g$. Properties of the so-called ``hard thermal loops'', i.e. the dominant contributions to amplitudes with soft external lines, find in this appr...
1993-01-13
2009-10-22
[ "hep-ph" ]
Jean-Paul BLAIZOT and Edmond IANCU (Service de Physique Th\'eorique CE-Saclay, 91191 Gif-sur-Yvette, France)
hep-ph/9301232
Heavy Charged Leptons in an $SU(3)_L\otimes U(1)_N$ Model
We consider an $SU(3)_L\otimes U(1)_N$ model for the electroweak interactions which includes extra charged leptons which do not mix with the known leptons. These new leptons couple to $Z^0$ only through vector currents. We consider constraints on the mass of one of these leptons coming from the $Z^0$-width and from the...
1993-01-12
2009-10-22
[ "hep-ph" ]
V. Pleitez and M.D. Tonasse