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hep-ph/9211244
Semileptonic Inclusive B--Decays and the Determination of $|V_{ub}|$ from QCD Sum Rules
We calculate the electron spectrum of semileptonic decays of B-mesons into non-charmed hadrons. The shape of the spectrum obtained from QCD sum rules is in general agreement with quark model calculations. At high electron energies the decrease of the spectrum is less steep than predicted by Altarelli et al. Our analysi...
1992-11-13
2008-11-26
[ "hep-ph" ]
P. Ball, V.M. Braun, H.G. Dosch
hep-ph/9211241
Antimatter in the Universe
Cosmological models which predict a large amount of antimatter in the Universe are reviewed. Observational signatures and searches for cosmic antimatter are briefly considered. A short discussion of new long range forces which might be associated with matter and antimatter is presented.
1992-11-12
2009-10-22
[ "hep-ph" ]
A. Dolgov
hep-ph/9211240
Debajyoti Choudhury
Gluon fusion into a very heavy neutrino pair by Higgs exchange is shown to lead to substantial production cross sections at $pp$ supercolliders even without any extra generation of quarks. Rates are calculated for scalar as well as pseudoscalar Higgs. The angular correlation between dileptons emerging from the decays o...
1992-11-12
2009-10-22
[ "hep-ph" ]
Rohini M. Godbole and Probir Roy
hep-ph/9211239
Effective Hadron Dynamics: From Meson Masses to the Proton Spin Puzzle
We construct a three flavor chiral Lagrangian of pseudoscalars and vectors with special emphasis on the symmetry breaking terms. Comparing tree level two and three point functions with experiment allows us to first, fix the parameters of the model (including the light quark mass ratios) and second, to predict $m(K^{*+}...
1992-11-11
2009-10-22
[ "hep-ph" ]
J. Schechter, A. Subbaraman and H. Weigel
hep-ph/9211238
Properties of perturbative multi-particle amplitudes in $\phi^k$ and $O(N)$ theories
Threshold amplitudes are considered for multi-particle production in $\phi^k$ and $O(N) ~\phi^4$ theories. It is found that the disappearance of tree-level threshold amplitudes of $2$ on-shell particles producing a large number of particles occurs in $\phi^k$ theory only for $k=3$ and $k=4$. The one-loop correction to ...
1992-11-11
2009-10-22
[ "hep-ph" ]
B.H. Smith
hep-ph/9211237
Multiscalar production amplitudes beyond threshold
We present exact tree-order amplitudes for $H^* \to n~H$, for final states containing one or two particles with non-zero three-momentum, for various interaction potentials. We show that there are potentials leading to tree amplitudes that satisfy unitarity, not only at threshold but also in the above kinematical config...
1992-11-11
2009-10-22
[ "hep-ph" ]
E.N. Argyres, C.G. Papadopoulos and R. Kleiss
hep-ph/9211236
Lepton Number Violating Radiative $W$ Decay in Models with R-parity Violation
Models with explicit R-parity violation can induce new rare radiative decay modes of the $W$ boson into single supersymmetric particles which also violate lepton number. We examine the rate and signature for one such decay, $W\rightarrow \tilde l\gamma$, and find that such a mode will be very difficult to observe, due ...
1992-11-10
2009-10-22
[ "hep-ph" ]
T.G. Rizzo
hep-ph/9211235
COBE and SUSY
We show that supersymmetry automatically leads to density fluctuations $\Delta T/T\sim6\times10^{-6}$ in agreement with the recent COBE measurement.
1992-11-09
2007-05-23
[ "hep-ph" ]
Lawrence Connors, Ashley J. Deans and John S. Hagelin
hep-ph/9211234
A Separate Higgs?
We investigate the possibility of a multi-Higgs doublet model where the lightest neutral Higgs boson ($h^0$) decouples from the fermion sector. We are partially motivated by the four $\ell^+\ell^-\gamma\gamma$ events with $M_{\gamma\gamma}\simeq60$\,GeV recently observed by the L3 collaboration, which could be a signal...
1992-11-09
2007-05-23
[ "hep-ph" ]
V. Barger, N.G. Deshpande, J.L. Hewett, and T.G. Rizzo
hep-ph/9211233
Anomalous prompt photon production in hadronic collisions at low-$x_T$
We investigate the discrepancy that exists at low-$x_T=2p_T/\sqrt{s}$ between the next--to--leading order QCD calculations of prompt photon production and the measured cross section. The central values of the measured cross section are of order 100\% larger than QCD predictions in this region. It has been suggested tha...
1992-11-09
2009-10-22
[ "hep-ph" ]
Damien Pierce
hep-ph/9211232
Implications of LEP Results for SO(10) Grandunification with Two Intermediate Stages
We consider the breaking of the grand unification group $SO(10)$ to the standard model gauge group through several chains containing two intermediate stages. Using the values of the gauge coupling constants at scale $M_Z$ derived from recent LEP data, we determine the range of their intermediate and unification scales....
1992-11-09
2009-10-22
[ "hep-ph" ]
N.G. Deshpande, E. Keith, Palash B. Pal
hep-ph/9211230
Radiatively Corrected Bound on the Light Higgs Mass in a Minimal Non Minimal Supersymmetric Standard Model
The neutral Higgs sector of the Minimal non Minimal Supersymmetric Standard Model is considered. By effective potential and R.G.E. supported method; an upper bound of the lightest Higgs is analysed. From the request of perturbativity of the coupling in the superpotential, adding the leading stop top contributions, the ...
1992-11-09
2007-05-23
[ "hep-ph" ]
D. Comelli (Dept. of Theorical Physics, University of Trieste and INFN sez.di Trieste)
hep-ph/9211229
Casimir Energy in the Skyrme Model
The so called Casimir energy embodies the O($(N_c)^0$) contribution to the skyrmion mass according to the semi-classical expansion theory of solitons. We claim that this contribution can be accurately estimated despite the fact that some of the counterterms, provided in principle by chiral perturbation theory, are not ...
1992-11-09
2007-05-23
[ "hep-ph" ]
B. Moussallam
hep-ph/9211231
Fermi-Dirac corrections to relic abundances
We derive an equation for the evolution of the number density of a massive particle species in the early Universe, which correctly accounts for the Fermi-Dirac (FD) statistics. The FD-corrections are sizable and potentially important if the decoupling from the thermal equilibrium takes place at temperatures of the orde...
1992-11-09
2009-10-22
[ "hep-ph" ]
A. D. Dolgov and K. Kainulainen
hep-ph/9211228
Proposed Tests for Minimal SU(5) Supergravity at Fermilab, Gran Sasso, SuperKamiokande, and LEP
A series of predictions are worked out in order to put the minimal $SU(5)$ supergravity model under experimental test. Using the two-loop gauge coupling renormalization group equations, with the inclusion of supersymmetric threshold corrections, we calculate a new value for the proton decay rate in this model and find ...
1992-11-08
2009-08-25
[ "hep-ph" ]
J. Lopez, D. Nanopoulos, H. Pois, and A. Zichichi
hep-ph/9211227
Violation of the Bjorken Sum Rule in QCD
We show that the Bjorken sum rule for the first moment of the polarized nucleon structure function $g_1$ is not necessarily satisfied in QCD if the axial anomaly is taken into account. We argue that nonperturbative QCD effects should lead to a violation of the sum rule of the order of the percentage isospin violation i...
1992-11-07
2009-10-22
[ "hep-ph" ]
Stefano Forte
hep-ph/9211217
A Possible Measurement of CP-Violation in B0-decays by ATLAS on LHC
A possibility to measure CP-violation in B0-decays by ATLAS experiment was investigated. With one year of running at luminosity 10^33 cm-2s-1 with a muon pt-trigger threshold of 20GeV and rapidity coverage eta<2.5 of the tracking detector the rate of 1490 events B0->J/psi->mumupipi can be reached.
1992-11-06
2007-05-23
[ "hep-ph" ]
Maria Smizanska & Julius Hrivnac
hep-ph/9211215
"Vortex Solution in a Multi-Higgs System and Its Physical Implication,"
Classical vortex solutions in $(1+2)$-dimensional multi-Higgs systems are studied. In particular the existence of such a solution requires equal characteristic lengths and a specific relation between the ratio of the two Higgs vacuum expectation values and the couplings in the Higgs potential, if $\lambda_3\neq 0$.
1992-11-06
2009-10-22
[ "hep-ph", "hep-th" ]
HoSeong La
hep-ph/9211216
On Constraints for Heavy-Meson Form Factors
We examine the recent work of de Rafael and Taron where model-independent bounds on the Isgur-Wise function are presented. We first argue that the bounds cannot hold in as much generality as implied. We show that the effects of resonances omitted in their discussion (such as heavy-heavy ``onium'' states below threshold...
1992-11-06
2009-10-22
[ "hep-ph" ]
Benjamin Grinstein and Paul F. Mende
hep-ph/9211220
Critical Temperature for the $\LAMBDA (\PHI^{4})_{4}$ Theory within the $\DELTA$ -Expansion
We apply the $\delta$-expansion perturbation scheme to the $\lambda \phi_{4}$ self-interacting scalar field theory in 3+1 D at finite temperature. In the $\delta$-expansion the interaction term is written as $\lambda (\phi^{2})^{1 + \delta}$ and $\delta$ is considered as the perturbation parameter. We compute, in this ...
1992-11-06
2007-05-23
[ "hep-ph" ]
Rudnei O. Ramos
hep-ph/9211218
Quantum Corrections to Nucleation Rates
In this paper we show how to compute in a consistent way nucleation rates in field theory at finite temperatures, with metastable vacuum. Using the semiclassical approach in field theory at finite temperature we show that the prefactor term can be calculated explicitly (in the thin-wall approximation) and that the same...
1992-11-06
2008-02-03
[ "hep-ph" ]
G.C.Marques and Rudnei O.Ramos
hep-ph/9211221
Small Angle Polarization in High Energy P--P Scattering Through Nonperturbative Chiral Symmetry Breaking
We show that a large anomalous contribution due to nonperturbative instanton-like gluonic field configurations to the axial charge of the proton implies high-energy spin effects in $p-p$ elastic scattering. This is the same mechanism which is responsible for anomalous baryon number violation at high energy in the stand...
1992-11-06
2009-10-22
[ "hep-ph" ]
Mauro Anselmino and Stefano Forte
hep-ph/9211226
Simply Modeling Meson HQET
A simple relativistic model of heavy-quark-light-quark mesons is proposed. In an expansion in inverse powers of the heavy quark mass we find that all zeroth and first order heavy quark symmetry relations are satisfied. The main results are: - the difference between the meson mass and the heavy quark mass plays a signif...
1992-11-06
2009-10-22
[ "hep-ph" ]
B. Holdom and M. Sutherland
hep-ph/9211222
Analyticity and the Isgur-Wise Function
We reconsider the recent derivation by de Rafael and Taron of bounds on the slope of the Isgur-Wise function. We argue that one must be careful to include cuts starting below the heavy meson pair production threshold, arising from heavy quark-antiquark bound states, and that if such cuts are properly accounted for then...
1992-11-06
2010-11-01
[ "hep-ph" ]
Adam F. Falk, Michael Luke and Mark B. Wise
hep-ph/9211224
SU(16) grandunification: breaking scales, proton decay and neutrino magnetic moment
We give a detailed renormalization group analysis for the SU(16) grandunified group with general breaking chains in which quarks and leptons transform separately at intermediate energies. Our analysis includes the effects of Higgs bosons. We show that the grandunification scale could be as low as $\sim 10^{8.5}$ GeV an...
1992-11-06
2009-10-22
[ "hep-ph" ]
N.G. Deshpande, E. Keith, and Palash B. Pal
hep-ph/9211219
Thermal Fluctuations and Validity of the 1-Loop Effective Potential
We examine the validity of the 1-loop approximation to the effective potential at finite temperatures and present a simple test for its reliability. As an application we study the standard electroweak potential, showing that for a Higgs mass above 70 GeV, and afirly independent of the top mass (with $m_{t} > 90 GeV$, t...
1992-11-06
2009-10-22
[ "hep-ph" ]
Marcelo Gleiser and Rudnei O. Ramos
hep-ph/9211223
On the Limits of Chiral Perturbation Theory
We consider the relation between the breakdown scale of chiral perturbation theory, $\Lambda_\chi$, for large values of $N$ (flavor), and the scale associated with ``new" physical thresholds. This question is addressed using both the linear $\sigma$ model and an asymptotically-free gauge theory to describe the high ene...
1992-11-06
2009-10-22
[ "hep-ph" ]
Thomas Appelquist and John Terning
hep-ph/9211225
Final-State Interaction of Longitudinal Vector Bosons
In the standard Higgs model of electroweak symmetry breaking, the Higgs boson is associated with both vector-boson and fermion mass generation. In contrast, we discuss a two-Higgs-doublet model in which these masses are associated with two different scalar bosons. We show that the Higgs boson associated with vector-bos...
1992-11-06
2008-11-26
[ "hep-ph" ]
J.-L. Basdevant, E. L. Berger, D. Dicus, C. Kao and S. Willenbrock
hep-ph/9211212
Scattering with Baryon Number Violation -- The Case of Higgs Particle Production --
\noindent A formalism based on path-integral expression of time-evolution operator during tunneling at a finite energy proposed by the authors is applied to $SU(2)$ gauge-Higgs system to produce Higgs particles with $\Delta B=1$. Instead of starting from instanton tunneling at the zero energy, a classical bounce soluti...
1992-11-05
2017-02-01
[ "hep-ph" ]
K.Funakubo, S.Otsuki, K.Takenaga and F.Toyoda
hep-ph/9211214
Neutrino Mixing due to a Violation of the Equivalence Principle
Massless neutrinos will mix if their couplings to gravity are flavor dependent, i.e., violate the principle of equivalence. Because the gravitational interaction grows with neutrino energy, the solar neutrino problem and the recent atmospheric neutrino data may be simultaneously explained by violations at the level of ...
1992-11-05
2008-11-26
[ "hep-ph" ]
J. Pantaleone, A. Halprin, C.N. Leung
hep-ph/9211213
On the role of vector mesons in topological soliton stability
Isospin one vector mesons (in particular the $\rho$) are usually described as massive Yang-Mills particles in the chiral Lagrangian. We investigate some aspects of an alternative approach in the soliton sector. It is found that the soliton is stable in very much the same way as with the $\omega$-meson and that spontane...
1992-11-05
2009-10-22
[ "hep-ph" ]
A. Abada, D. Kalafatis and B. Moussallam
hep-ph/9211209
Systematic Study of Fermion Masses and Mixing Angles in Horizontal SU(2) Gauge Theory
Despite its great success in explaining the basic interactions of nature, the standard model suffers from an inability to explain the observed masses of the fundamental particles and the weak mixing angles between them. We shall survey a set of possible extensions to the standard model, employing an SU(2) ``horizontal'...
1992-11-04
2009-10-22
[ "hep-ph" ]
Donald S. Shaw and Ray R. Volkas
hep-ph/9211211
Self-consistent Improvement of the Finite Temperature Effective Potential
We present a self-consistent calculation of the finite temperature effective potential for $\lambda \phi^4$ theory, using the composite operator effective potential in which an infinite series of the leading diagrams is summed up. Our calculation establishes the proper form of the leading correction to the perturbative...
1992-11-04
2009-10-22
[ "hep-ph", "hep-th" ]
G. Amelino-Camelia and S.-Y. Pi
hep-ph/9211210
Evidence For SUSY from GUTS? Evidence For GUTS From SUSY!
We review the theoretical and experimental status of minimal grand unified theories (GUTS), contrasting the failure of minimal non-supersymmetric $SU(5)$ with the success of the minimal supersymmetric $SU(5)$ and minimal supersymmetric Flipped $SU(5)\times U(1)$ models. We show that a reasonable value for the universal...
1992-11-04
2007-05-23
[ "hep-ph" ]
John S. Hagelin and S. Kelley
hep-ph/9211208
Cosmology and Astrophysics 1992
I review recent developments in cosmology and astrophysics relevant to particle physics, focussing on the following questions: What's new in 1992? What have we learned since the last ICHEP meeting in 1990? and What are the prospects for the future? AMong the topics explicitly discussed are: COBE, Large Scale Structure,...
1992-11-03
2009-09-25
[ "hep-ph", "astro-ph" ]
Lawrence M. Krauss
hep-ph/9211201
On the COBE Discovery - for Pedestrians
A recent discovery by the COBE satellite is presented, and its importance discussed in the context of the physics of the early Universe. The various implications for our understanding of the structure of the Universe are outlined.
1992-11-02
2010-12-09
[ "hep-ph", "astro-ph" ]
Leszek Roszkowski
hep-ph/9211202
Flavour Distributions in the Nucleons: SU(2) Sea Asymmetry or Isospin Symmetry Breaking?
The Gottfried sum rule violation reported by the New Muon Collaboration(NMC) was interpreted as indication for a flavour asymmetry of the sea quark in the nucleons. We investigate the alternative possibility that isospin symmetry between the proton and the neutron is breaking. We examine systematically the consequences...
1992-11-02
2009-10-22
[ "hep-ph", "nucl-th" ]
Bo-Qiang Ma, Andereas Schaefer, and Walter Greiner
hep-ph/9211203
Bell's Inequality and $\tau$-Physics at LEP
In this talk given at the TAU92 Workshop, Columbus, OH, Sept. 92, we summarize results presented in more detail in a recent paper by S. Abel, M. Dittmar and the author where we gave a general proof that Bell's inequality can not be tested at a collider experiment. In particular, a measurement of correlated tau-spins at...
1992-11-02
2007-05-23
[ "hep-ph" ]
Herbert Dreiner
hep-ph/9211265
Dynamical confinement in bosonized QCD2
In the bosonized version of two dimensional theories non trivial boundary conditions (topology) play a crucial role. They are inevitable if one wants to describe non singlet states. In abelian bosonization, color is the charge of a topological current in terms of a non-linear meson field. We show that confinement appea...
1992-11-02
2009-10-22
[ "hep-ph" ]
A. Ferrando and V. Vento
hep-ph/9211204
R-Parity Violation at HERA
We summarize the signals at HERA in supersymmetric models with explicitly broken R-parity. As the most promising case, we consider in detail the resonant production of single squarks through an operator $L_1Q_i{ \bar D}_j$, a production process analogous to that for leptoquarks. However, the dominant decay of the squar...
1992-11-02
2009-10-22
[ "hep-ph" ]
Jon Butterworth and Herbert Dreiner
hep-ph/9211207
Ansatz for Quark, Charged Lepton, and Neutrino Masses in SUSY GUTS
We extend a fermion mass matrix Ansatz by Giuduce to include neutrino masses. The previous predictions are maintained. With two additional parameters, a large Majorana neutrino mass and a hierarchy factor, we have seven {\it further} low energy predictions: the masses of the neutrinos, the mixing angles and the phase i...
1992-11-02
2009-10-22
[ "hep-ph" ]
H. Dreiner, G. K. Leontaris and N. D. Tracas
hep-ph/9211205
QCD Corrections to the Light Higgs Boson Decay into a Charm- Anticharm or Bottom- Antibottom Pair within the Minimal Supersymmetric Model
We present the results of the contributions to the decay rate of the lightest Higgs particle into a charm-anticharm and bottom-antibottom pair within the minimal supersymmetric standard model when scalar quarks and a gluino are taken within the relevant loop diagrams. We show that in the case where the vacuum expectati...
1992-11-02
2011-01-25
[ "hep-ph" ]
Heinz K\"onig
hep-ph/9211206
SO(10) Cosmic Strings and Baryon Number Violation
SO(10) cosmic strings formed during the phase transition Spin(10) $\rightarrow$ SU(5) $\times{\cal Z}_2$ are studied. Two types of strings --- one effectively Abelian and one non-Abelian --- are constructed and the string solutions are calculated numerically. The non-Abelian string can catalyze baryon number violation ...
1992-11-02
2009-10-22
[ "hep-ph", "astro-ph" ]
Chung-Pei Ma
hep-ph/9211264
About the realization of chiral symmetry in QCD2
Two dimensional massless Quantum Chromodynamics presents many features which resemble those of the true theory. In particular the spectrum consists of mesons and baryons arranged in flavor multiplets without parity doubling. We analyze the implications of chiral symmetry, which is not spontaneously broken in two dimens...
1992-11-02
2009-10-22
[ "hep-ph" ]
A. Ferrando and V. Vento
hep-ph/9211274
Nucleon and delta masses in QCD
Using the positivity of the path integral measure of $QCD$ and defining a structure for the quark propagator in a background field according to the fluxon scenario for confinement, we calculate and compare the correlators for nucleon and delta. From their shape we elucidate about the origin of their mass difference, wh...
1992-11-02
2010-11-01
[ "hep-ph" ]
M. Rafecas and V. Vento
hep-ph/9210278
On the High $T$ Phase Transition in the Gauged $SU(2)$ Higgs Model
We study the effective field theory of a weakly coupled 3+1d gauged $\phi^4$ type model at high temperature. Our model has $4N$ real scalars ($N$ complex Higgs doublets) and a gauge group $SU(2)$ which is spontaneously broken by a nonzero scalar field $vev$ at zero temperature. We find, for sufficiently large $N$, ...
1992-10-30
2009-10-22
[ "hep-ph" ]
Vidyut Jain and Aris Papadopoulos
hep-ph/9210281
Structure functions for large $x$ and renormalization of Wilson loops
We discuss the relation between partonic distributions near the phase space boundary and Wilson loop expectation values calculated along paths partially lying on the light-cone. Due to additional light-cone singularities, multiplicative renormalizability for these expectation values is lost. Nevertheless we establish t...
1992-10-30
2008-11-26
[ "hep-ph" ]
G.P.Korchemsky and G.Marchesini
hep-ph/9210280
The Simplest, String-Derivable, Supergravity Model and its Experimental Predictions
We present the simplest, string-derivable, supergravity model and discuss its experimental consequences. This model is a new string-inspired flipped $SU(5)$ which unifies at the string scale $M_U=10^{18}\GeV$ due to the introduction of an additional pair of \r{10},\rb{10} flipped $SU(5)$ representations which contain n...
1992-10-30
2009-08-25
[ "hep-ph" ]
J. Lopez, D. Nanopoulos, and A. Zichichi
hep-ph/9210279
Tevatron Mass Limits for Heavy Quarks Decaying via Flavor Changing Neutral Current
The dimuon and dielectron data from the Tevatron $\bar pp$ collider are used to probe for heavy quarks, which decay dominantly via flavour changing neutral current. Depending on whether the $FCNC$ decay occurs at the tree or loop level, one gets a lower mass limit of 85 or 75 GeV. The former applies to singlet, vector ...
1992-10-30
2008-11-26
[ "hep-ph" ]
Biswarup Mukhopadhyaya and D.P. Roy
hep-ph/9210274
A Comment on the Strong Interactions of Color-Neutral Technibaryons
We estimate the cross section for the scattering of a slow, color-neutral technibaryon made of colored constituents with nuclei. We find a cross section of order $A^2\ 10^{-45}$ cm$^2$, where $A$ is the atomic number of the nucleus. Even if technibaryons constitute the dark matter in the galactic halo, this is too smal...
1992-10-29
2009-10-22
[ "hep-ph", "astro-ph" ]
R. Sekhar Chivukula, Andrew G. Cohen, Michael Luke, and Martin J. Savage
hep-ph/9210276
Critical Constraints on Chiral Hierarchies
We consider the constraints that critical dynamics places on models with a top quark condensate or strong extended technicolor (ETC). These models require that chiral-symmetry-breaking dynamics at a high energy scale plays a significant role in electroweak symmetry breaking. In order for there to be a large hierarchy b...
1992-10-29
2009-10-22
[ "hep-ph", "hep-lat" ]
R. Sekhar Chivukula, Mitchell Golden, and Elizabeth H. Simmons
hep-ph/9210275
Heavy to Light Semileptonic Transitions in the Heavy Quark Effective Theory
The scaling behavior of semileptonic form-factors in Heavy to Light transitions is studied in the Heavy Quark Effective Theory. In the case of $H\rightarrow \pi e\nu$ it is shown that the same scaling violations affecting the heavy meson decay constant will be present in the semileptonic form-factors.
1992-10-29
2007-05-23
[ "hep-ph" ]
G. Burdman
hep-ph/9210277
Threshold Effects on Heavy Quark Production in $\gamma\gamma$ Interactions
The exchange of gluons between heavy quarks produced in $e^+e^-$ interactions results in an enhancement of their production near threshold. We study QCD threshold effects in $\gamma\gamma$ collisions. The results are relevant to heavy quark production by beamstrahlung and laser back-scattering in future linear collider...
1992-10-29
2010-11-01
[ "hep-ph" ]
O.J.P. Eboli, M.C. Gonzalez-Garcia, F. Halzen, and S.F. Novaes
hep-ph/9210273
A More Effective Potential
In theories with spontaneous symmetry breaking, the conventional effective potential possesses a defective loop expansion. For such theories, the exact effective potential $V(\phi_c,T)$ is real and convex, but its perturbative series is complex and concave at small $\phi_c$ and $T$. A more effective potential is availa...
1992-10-29
2009-10-22
[ "hep-ph" ]
Kevin Cahill
hep-ph/9210271
Search for Dileptons in Z decay
The lepton family number violation $Z$ boson decay, $Z \to e^-e^-\mu^+\mu^+$ or $e^+e^+\mu^-\mu^-$, mediated by a dilepton, e.g. from an SU(15) theory, is calculated. The branching ratio of such exotic decay for allowed dilepton masses is found to be smaller than 10$^{-10}$.
1992-10-28
2009-10-22
[ "hep-ph" ]
P. H. Frampton, Daniel Ng, T.W. Kephart, T. C. Yuan
hep-ph/9210270
Search for Heavy Leptons at Hadron Colliders
Four models are considered which contain heavy leptons beyond the three families of the standard model. Two are fourth-generation extensions of the standard model in which the right-handed heavy leptons are either isosinglets or in an isodoublet; the other two are motivated by the aspon model of CP violation. In all th...
1992-10-28
2010-11-01
[ "hep-ph" ]
Paul H. Frampton, Daniel Ng, Marc Sher and Yao Yuan
hep-ph/9210272
New Contribution to Coherent neutralino-Nucleus Scattering
We discuss coherent scattering between supersymmetric neutralinos and nuclei via an effective neutralino-gluon interaction. We identify two new classes of diagrams which are not treated in the existing literature. These occur at the same order of perturbation theory as the previously considered diagrams. The new contri...
1992-10-28
2009-10-22
[ "hep-ph" ]
Mauel Drees and Mihoko M. Nojiri
hep-ph/9210269
Nonperturbative QCD efects in weak hadronic decays
QCD-based analysis of nonfactorizable parts of weak nonleptonic amplitudes is reported. Nonperturbative effects due to soft gluon exchange play a key role leading to the emergence of a dynamical rule of discarding $1/N_c$ corrections.
1992-10-27
2007-05-23
[ "hep-ph" ]
B. Blok and M. Shifman
hep-ph/9210267
New QCD Effects at Large x
In heavy quark production at large Feynman $x$ there are two hardness scales, one given by the heavy quark pair mass $\M^2$\ and the other by $\Lambda_{QCD}^2/(1-x)$. When these two scales are comparable, the twist expansion of Perturbative QCD breaks down. We discuss the dynamics in this new QCD limit, where $\mu^2=\M...
1992-10-27
2010-11-01
[ "hep-ph" ]
Paul Hoyer
hep-ph/9210268
Heavy-Quark Baryons as Skyrmions
I discuss recent development on the description of heavy-quark (such as charmed and bottom) baryons as one or more heavy mesons "wrapped" by a skyrmion. Amazingly enough, such a description naturally arises when light-quark chiral symmetry and heavy-quark spin symmetry are incorporated in an effective Lagrangian. I int...
1992-10-27
2007-05-23
[ "hep-ph" ]
Mannque Rho (Saclay)
hep-ph/9210266
Radiative corrections to the decay H==>hh in the Minimal Supersymmetric Standard Model
We set up a suitable renormalization programme for the one-loop computation of the decay rate Gamma(H==>hh) in the Minimal Supersymmetric extension of the Standard Model. We then perform an explicit diagrammatic calculation, including the full contributions from top, bottom, stop and sbottom loops. We find that, for ta...
1992-10-27
2011-01-27
[ "hep-ph" ]
A.Brignole and F.Zwirner
hep-ph/9210265
Weak Radiative Hyperon Decays in Chiral Perturbation Theory
The parity-conserving $a$ and parity-violating $b$ amplitudes for weak radiative hyperon decay are studied using chiral perturbation theory. The imaginary parts of $a$ and $b$ are computed using unitarity. The real part of $b$ is dominated by a one-loop infrared divergent graph which is computed. The real part of $a$ h...
1992-10-27
2008-11-26
[ "hep-ph" ]
Elizabeth Jenkins, Michael Luke, Aneesh V. Manohar, and Martin J. Savage
hep-ph/9210262
A Bound on the Energy Loss of Partons in Nuclei
We derive a quantum mechanical upper bound on the amount of radiative energy loss suffered by high energy quarks and gluons in nuclear matter. The bound shows that the nuclear suppression observed in quarkonium production at high $x_F$ cannot be explained in terms of energy loss of the initial or final parton states. W...
1992-10-26
2009-09-11
[ "hep-ph" ]
Stanley J. Brodsky and Paul Hoyer
hep-ph/9210264
Three Dimensional Statistical Field Theory for Density Fluctuations in Heavy-Ion Collsiions
A statistical field theory of particle production is presented using a gaussian functional in three dimensions. Identifying the field with the particle density fluctuation results in zero correlations of order three and higher, while the second order correlation function is of a Yukawa form. A detailed scheme for proje...
1992-10-26
2015-06-25
[ "hep-ph" ]
H. C. Eggers, H-Th. Elze and I. Sarcevic
hep-ph/9210263
Intermittency and Multidimensional Correlations
We review recent experimental results on intermittency and multidimensional particle correlations in high-energy leptonic, hadronic and nuclear collisions. We discuss different theoretical models, including self-similar cascading and QCD parton showers, models with phase transitions and the three-dimensional statistica...
1992-10-26
2009-10-22
[ "hep-ph" ]
I. Sarcevic
hep-ph/9210261
Topological Defect Models of Structure Formation After the COBE Discovery of CMB Anisotropies
The COBE satellite has discovered anisotropies in the cosmic microwave background (CMB) consistent with a scale invariant spectrum of density perturbations. As reviewed in this lecture, topological defect models of structure formation generically produce such a spectrum. We give a summary of the cosmic string and globa...
1992-10-24
2007-05-23
[ "hep-ph", "astro-ph" ]
Robert H. Brandenberger (Brown University)
hep-ph/9210260
Universal Evolution of CKM Matrix Elements
We derive the two-loop evolution equations for the Cabibbo-Kobayashi-Maskawa matrix. We show that to leading order in the mass and CKM hierarchies the scaling of the mixings $|V_{ub}|^2$, $|V_{cb}|^2$, $|V_{td}|^2$, $|V_{ts}|^2$ and of the rephase-invariant CP-violating parameter $J$ is universal to all orders in pertu...
1992-10-23
2009-09-15
[ "hep-ph" ]
V. Barger, M. S. Berger and P. Ohmann
hep-ph/9210259
Quark model calculation of $\eta \to l^+ l^-$ to all orders in the bound state relative momentum
The electromagnetic box diagram for the leptonic decays of pseudoscalar mesons in the quark model is evaluated to all orders in ${\bf p} / m_q$, where ${\bf p}$ is the relative three-momentum of the quark-antiquark pair and $m_q$ is the quark mass. We compute $B_P \equiv \Gamma(\eta \to l^+ l^-) / \Gamma(\eta \to \gamm...
1992-10-23
2009-10-22
[ "hep-ph" ]
B. Margolis, J. Ng, M. Phipps, and H. D. Trottier
hep-ph/9210258
Non--perturbative evidence for non--decoupling of heavy fermions
We investigate, using a $1/N$ expansion, the behavior of a parameter in the scalar--fermion sector of the standard model that shows perturbative non--decoupling as the fermion becomes heavy. This low energy parameter is related to the $S$ parameter defined through the $W_3-B$ vacuum polarization tensor. We obtain the l...
1992-10-23
2008-11-26
[ "hep-ph" ]
Kenichiro Aoki, Santiago Peris
hep-ph/9210256
Generation Mass Hierarchy in Superstring Derived Models
I discuss the problem of generation mass hierarchy in the context of realistic superstring models which are constructed in the free fermionic formulation. These models correspond to models which are compactified on $Z_2\times Z_2$ orbifold. I suggest that the hierarchy among the generations results from horizontal symm...
1992-10-22
2009-10-22
[ "hep-ph", "hep-th" ]
Alon E. Faraggi
hep-ph/9210257
Tau Decay Puzzles and Possible Light Gluinos
The relation of the strong coupling constant as measured in tau decay to other low energy determinations is considered with special attention to its impact on the question of the possible existence of light gluinos.
1992-10-22
2007-05-23
[ "hep-ph" ]
L. Clavelli
hep-ph/9210254
Intermittency and Particle Correlations: Theory
We review recent theoretical developments in understanding the intermittency phenomenon observed in high-energy leptonic, hadronic and nuclear collisions. In particular, we discuss self-similar cascading and QCD parton showers, models with models with phase transitions, and the three-dimensional statistical field theor...
1992-10-21
2009-10-22
[ "hep-ph" ]
Ina Sarcevic
hep-ph/9210255
Analytical on-shell QED results: 3-loop vacuum polarization, 4-loop beta-function and the muon anomaly
We present the results of analytical calculations of the 3-loop contributions to the asymptotic photon vacuum polarization function, in the on shell scheme, and of the 4-loop contributions to the on shell QED beta-function. These are used to evaluate various 4-loop and 5-loop contributions to the muon anomaly. Our anal...
1992-10-21
2019-08-17
[ "hep-ph", "hep-th" ]
D.J. Broadhurst, A.L. Kataev and O.V. Tarasov
hep-ph/9210250
The fermion mass problem
In this talk I review the `puzzles' associated with the fermion mass matrices and describe some recent attempts to resolve them, at least partially. Models which attempt to explain the observed mass hierarchy as arising from radiative corrections are discussed. I then scrutinize possible inter--relations among quark an...
1992-10-20
2007-05-23
[ "hep-ph" ]
K.S. Babu
hep-ph/9210251
Heavy top quark from Fritzsch mass matrices
It is shown, contrary to common belief, that the Fritzsch ansatz for the quark mass matrices admits a heavy top quark. With the ansatz prescribed at the supersymmetric grand unified (GUT) scale, one finds that the top quark may be as heavy as 145 GeV, provided that tan$\beta$ (the ratio of the vacuum expectation values...
1992-10-20
2010-11-01
[ "hep-ph" ]
K.S. Babu and Q. Shafi
hep-ph/9210252
Radiative Origin of the Fermion Mass Hierarchy: A Realistic and Predictive Approach
The up-down splitting within quark families increases with the family number: m_u ~ m_d, m_c > m_s, m_t >> m_b. We show an approach that realizes this feature of the spectrum in a natural way. We suggest that the mass hierarchy is first generated by radiative effects in a sector of heavy isosinglet fermions, and then p...
1992-10-20
2008-02-03
[ "hep-ph" ]
Zurab Berezhiani and Riccardo Rattazzi
hep-ph/9210249
Avalanche in the Valley (Fermions, Anomaly and Unitarity in High-Energy Electroweak Interactions)
Problems related to fermions, unitarity and chiral anomaly in high energy electroweak interactions, are investigated. Particular attention is paid to the correct functional integration over fermion fields in the background of instanton-anti\-instanton type configurations. This leads to an expansion of correlation funct...
1992-10-20
2011-07-19
[ "hep-ph" ]
R. Guida and K. Konishi
hep-ph/9210253
Static and Dynamic Critical Phenomena at a Second Order QCD Phase Transition
In QCD with two flavors of massless quarks, the chiral phase transition is plausibly in the same universality class as the classical four component Heisenberg antiferromagnet. Therefore, renormalization group techniques developed in the study of phase transitions can be applied to calculate the critical exponents which...
1992-10-20
2009-10-22
[ "hep-ph", "astro-ph", "hep-lat" ]
K. Rajagopal and F. Wilczek
hep-ph/9210248
Nuclear Axial-Charge Transitions in Chiral Perturbation Theory
We develop a systematic chiral perturbation expansion for the calculation of meson-exchange currents in nuclei and apply the formalism to nuclear axial currents. We summarize the principal results of such a calculation to one loop order on nuclear axial-charge transitions which provides a strong support to the conjectu...
1992-10-20
2007-05-23
[ "hep-ph" ]
Tae-Sun Park, Dong-Pil Min and Mannque Rho
hep-ph/9210245
Scaling limit of a non-relativistic model
I calculate the structure function for scattering from the two-body bound state in its lowest level in a non-relativistic model of confined scalar ``quarks'' of masses $m_A$ and $m_B$. The scaling limit in $x={\bf q}^2/2(m_A+m_B)q^0$ exists and is non-vanishing only for the values $x=m_A/(m_A+m_B)$ and $x=m_B/(m_A+m_B)...
1992-10-19
2009-10-22
[ "hep-ph" ]
O.W. Greenberg
hep-ph/9210247
The Perturbative Onset of Multiparticle Production in Weak Interactions
We use perturbation theory to estimate the energy scale beyond which multiparticle final states become a dominant feature of high energy weak interactions. Using estimates from a weak parton model and comparing two, three and four body final states we deduce that multiparticle states become important at energy scales i...
1992-10-19
2011-07-19
[ "hep-ph" ]
D.A. Morris and R. Rosenfeld
hep-ph/9210244
Zeros of Tree-Level Amplitudes at Multi-Boson Thresholds
Propagation of particles with emission of arbitrary number of identical bosons all being at rest is considered. It is shown that in certain models the tree-level amplitudes for production of $n$ scalar bosons by two incoming particles are all equal to zero at the threshold starting from some small number $n$. In partic...
1992-10-19
2009-10-22
[ "hep-ph" ]
M.B. Voloshin
hep-ph/9210246
Chern-simon type photon mass from fermion electric dipole moments at finite temperature in 3+1 dimensions
We study the low energy effective field theory of fermions with electric and magnetic dipole moments at finite temperature. We find that at one loop there is an interaction term of the Chern-Simon form ${\cal L_I}=m_\mu\>A_\nu {\tilde F}^{\mu\nu}$. The four vector $m_\mu \simeq d_i \mu_i m_i^2 ~{\partial_\mu}\>(ln T)$ ...
1992-10-17
2016-09-01
[ "hep-ph" ]
Subhendra Mohanty, S.N.Nayak and Sarira Sahu
hep-ph/9210241
Phenomenological Aspects of Supersymmetric Standard Models without Grand Unification
When the GUT relation on gaugino masses is relaxed, the mass and composition of the lightest neutralino are different from those in the GUT case. We discuss its phenomenological implications on the relic abundance of the neutralinos and on superparticle searches. In particular, we focus on the case where the neutral co...
1992-10-16
2009-10-22
[ "hep-ph" ]
Satoshi Mizuta, Daniel Ng and Masahiro Yamaguchi
hep-ph/9210243
How Effective is the Effective Potential?
Motivated by bubble nucleation in first order phase transitions, we question the validity of the effective potential for inhomogeneous configurations. In an attempt to get some insight into the importance of derivative terms, we analyze a simple model, a kink in (1+1) dimensions and zero temperature. We evaluate the en...
1992-10-16
2014-11-17
[ "hep-ph", "hep-th" ]
Scott Dodelson and Ben-Ami Gradwohl
hep-ph/9210240
Gravitational Smearing of Minimal Supersymmetric Unification Predictions
A short and mean paper.
1992-10-16
2013-11-13
[ "hep-ph" ]
L.J. Hall and U. Sarid
hep-ph/9210242
Calculable Upper Limit on the Mass of the Lightest Higgs Boson in Any Perturbatively Valid Supersymmetric Theory
We show that there is a calculable upper limit on the mass of the lightest Higgs boson in any supersymmetric theory that remains perturbative up to a high scale . There are no restrictions on the Higgs sector, or the gauge group or particle content. We estimate the value of the upper limit to be $m_{\hcirc} < 146$ GeV ...
1992-10-16
2009-10-22
[ "hep-ph" ]
G.L. Kane, Chris Kolda, and James D. Wells
hep-ph/9210238
Proton Decay
The status of proton decay is described, including general motivations for baryon number violation, and the present and future experimental situation. Grand unification with and without supersymmetry is considered, including possible evidence from coupling constant unification and implications for proton decay and neut...
1992-10-15
2007-05-23
[ "hep-ph" ]
Paul Langacker
hep-ph/9210237
On an asymptotic estimate of the $n$-loop correction in perturbative QCD
A recently proposed method of estimating the asymptotic behaviour of QCD perturbation theory coefficients is critically reviewed and shown to contain numerous invalid mathematical operations and unsubstantiated assumptions. We discuss in detail why this procedure, based solely on renormalization group (RG) consideratio...
1992-10-15
2016-08-14
[ "hep-ph" ]
J.Ch\'yla, J.Fischer and P. Kol\'a\v{r}
hep-ph/9210239
Flavor Asymmetry of the Nucleon Sea: Consequences for Dilepton Production
Parton distributions derived from a chiral quark model that generates an excess of down quarks and antiquarks in the proton's sea satisfactorily describe the measured yields of muon pairs produced in proton-nucleus collisions. Comparison of dilepton yields from hydrogen and deuterium targets promises greater sensitivit...
1992-10-15
2009-05-05
[ "hep-ph", "nucl-th" ]
Estia J. Eichten, Ian Hinchliffe, and Chris Quigg
hep-ph/9210234
Post-Gaussian Varioational Method for the Nonlinear Schrodinger Equation
Gaussians to study soliton behavior and blowup in the nonlinear Schrodinger equation in arbitrary dimension d and with arbitrary nonlinearity parameter kappa
1992-10-14
2009-10-22
[ "hep-ph" ]
F.Cooper, H. Shepard, C Lucheroni and P. Sodano
hep-ph/9210235
Uncertainties in Coupling Constant Unification
The status of coupling constant unification in the standard model and its supersymmetric extension are discussed. Uncertainties associated with the input coupling constants, $m_{t}$, threshold corrections at the low and high scales, and possible nonrenormalizable operators are parametrized and estimated. A simple param...
1992-10-14
2009-10-22
[ "hep-ph" ]
Paul Langacker and Nir Polonsky
hep-ph/9210236
The SSC: Programme and Searches for New Particles
Talk presented at the Trieste Workshop on the Search for New Elementary Particles: Status and Prospects.
1992-10-14
2008-02-03
[ "hep-ph" ]
Benjamin Grinstein
hep-ph/9210233
Spontaneously Broken Technicolor and the Dynamics of Virtual Vector Technimesons
We propose spontaneously breaking technicolor, thus liberating techniquarks and suppressing large resonance contributions to the electroweak $S$ parameter. The dynamics is modeled by a fermion bubble approximation to a single massive techni--gluon exchange potential. This contains a Nambu--Jona-Lasinio model with addit...
1992-10-13
2009-10-22
[ "hep-ph" ]
Christopher T. Hill, Dallas C. Kennedy, Tetsuya Onogi, Hoi--Lai Yu
hep-ph/9210231
ETC With a GIM Mechanism
We construct an extended technicolor model of quarks and leptons which preserves a GIM mechanism. Furthermore, there is only a minimal technicolor sector, in accordance with recent precision measurements of electroweak parameters. We also show how to incorporate custodial SU(2) and massless neutrinos into such a model.
1992-10-13
2009-09-15
[ "hep-ph" ]
L. Randall
hep-ph/9210232
Testing ETC Generation of the Top Quark Mass
We consider constraints on models in which a top quark mass is generated through unenhanced extended technicolor interactions. The deviation in the $\rho$ parameter from unity and $B$--$\overline{B}$ mixing could be large, but given the uncertainties in strong dynamics and variations in the parameters of models, no con...
1992-10-13
2009-09-15
[ "hep-ph" ]
L. Randall
hep-ph/9210230
Observing Electroweak Symmetry Breaking at the SSC
In this talk we survey the SSC signals and backgrounds for the physics of electroweak symmetry breaking. We study the process $pp \rightarrow WWX$ and compute the rate for the ``gold-plated'' signals $W^\pm \rightarrow \ell^\pm \nu$ and $Z \rightarrow \ell^+\ell^-$ $(\ell = e,\mu)$ for a wide variety of models. We use ...
1992-10-13
2009-10-22
[ "hep-ph" ]
Jonathan A. Bagger
hep-ph/9210228
Improving the Effective Potential
A general procedure is presented how to improve the effective potential by using the renormalization group equation (RGE) in MS bar scheme. If one knows the L-loop effective potential and the RGE coefficient functions up to (L+1)-loop level, this procedure gives an improved potential which satisfies the RGE and contain...
1992-10-12
2009-10-22
[ "hep-ph" ]
Masako Bando, Taichiro Kugo, Nobuhiro Maekawa and Hiroaki Nakano
hep-ph/9210229
Improving the Effective Potential:Multi-Mass-Scale Case
Previously proposed procedure for improving the effective potential by using renormalization group equation (RGE) is generalized so as to be applicable to any system containing several different mass scales. If one knows L-loop effective potential and (L+1)-loop RGE coefficient functions, this procedure gives an improv...
1992-10-12
2017-02-01
[ "hep-ph" ]
Masako Bando, Taichiro Kugo, Nobuhiro Maekawa and Hiroaki Nakano
hep-ph/9210227
Computing Spectral Densities in Finite Temperature Field Theory
Convenient Cutkosky-like diagrammatic rules for computing the spectral densities of arbitrary two-point correlation functions in finite temperature field theory are derived. The approach is based on an explicit analytic continuation of imaginary-time Feynman diagrams and avoids the complications of real-time finite tem...
1992-10-10
2009-10-22
[ "hep-ph" ]
Sangyong Jeon