title: CP-Violating Lepton-Energy Correlation in e\bar{e}\to t\bar{t}

abstract:
  In order to observe a signal of possible CP violation in top-quark couplings,
we have studied energy correlation of the final leptons in $e^+e^-\to t\bar{t}
\to \ell^+\ell^-X / \ell^\pm X$ at future linear colliders. Applying the
recently-proposed optimal method, we have compared the statistical
significances of CP-violation-parameter determination using double- and
single-lepton distributions. We have found that the single-lepton-distribution
analysis is more advantageous.


title: Gravitational Violation of R Parity and its Cosmological Signatures

abstract:
  The discrete R-parity ($R_P$) usually imposed on the Supersymmetric (SUSY)
models is expected to be broken at least gravitationally. If the neutralino is
a dark matter particle its decay channels into positrons, antiprotons and
neutrinos are severely constrained from astrophysical observations. These
constraints are shown to be violated even for Planck-mass-suppressed
dimension-five interactions arising from gravitational effects. We perform a
general analysis of gravitationally induced $R_P$ violation and identify two
plausible and astrophysically consistent scenarios for achieving the required
suppression.


title: Baryon Asymmetry and Neutrino Mixing

abstract:
  In theories where $B-L$ is a spontaneously broken local symmetry, the
cosmological baryon asymmetry can be generated by the out-of-equilibrium decay
of heavy Majorana neutrinos. We study this mechanism assuming a similar pattern
of mixings and masses for leptons and quarks, as suggested by SO(10)
unification. This implies that $B-L$ is broken at the unification scale
$\Lambda_{\mbox{\scriptsize GUT}}\sim 10^{16}$ GeV, if $m_{\n_\m} \sim 3\cdot
10^{-3}$eV as preferred by the MSW explanation of the solar neutrino deficit.
The observed value of the baryon asymmetry, $n_B/s \sim 10^{-10}$, is then
obtained without any fine tuning of parameters.


title: Excited Fermion Contribution to Z Physics at One Loop

abstract:
  We investigate the effects induced by excited leptons at the one-loop level
in the observables measured on the $Z$ peak at LEP. Using a general effective
Lagrangian approach to describe the couplings of the excited leptons, we
compute their contributions to both oblique parameters and $Z$ partial widths.
Our results show that the new effects are comparable to the present
experimental sensitivity, but they do not lead to a significant improvement on
the available constraints on the couplings and masses of these states.


title: $k_{\perp}$-Factorization and Perturbative Invariants at Small $x$

abstract:
  I review the basic idea of $k_{\perp}$-factorization and its relation to
collinear factorization. Theoretical results in resummed perturbation theory
are summarized and the example of the heavy-flavour structure functions is
explicitly considered. Using these results one can investigate the small-$x$
behaviour of quantities that are independent of the non-perturbative parton
densities. In particular, one can introduce physical anomalous dimensions that
relate the scaling violations in different hadronic observables.


title: Solar neutrinos: Near-far asymmetry and just-so oscillations

abstract:
  We propose to study possible signals of just-so oscillations in
new-generation solar neutrino experiments by separating the events detected
when the earth is nearest to the sun (perihelion $\pm$~3~months) from those
detected when the earth is farthest from the sun (aphelion $\pm$~3~months). We
introduce a solar model independent near-far asymmetry, which is non-zero if
just-so oscillations occur. We apply our calculations to the kinetic energy
spectra of electrons induced by $^8$B solar neutrino interactions in the
SuperKamiokande and Sudbury Neutrino Observatory experiments. We show that the
sensitivity to the neutrino oscillation parameters can be increased by probing
the near-far asymmetry in selected parts of the electron energy spectra.


title:
Comment on Leptophobic Bosons and $\nu N$ Neutral Current Scattering
  Data

abstract:
  The relevance of existing $\nu N$ deep inelastic scattering data to models
containing a leptophobic neutral vector boson is discussed. It is shown that
this neutral current data is in good agreement with the Standard Model and
disfavors such a leptophobic boson.


title: New Limits on R-Parity Breakings in Supersymmetric Standard Models

abstract:
  New limits on couplings $\lambda^i_{jk}{''}$, which break both the baryon
number and the $R$--parity, are derived by using a new mechanism that
contributes to the neutron-anti-neutron oscillation. The constraints due to
proton decay and its potential phenomenology are also reexamined.


title: CP violation in B mesons using Dalitz plot asymmetries

abstract:
  We study CP violation in $B\to K^* \ell^+\ell^-$ using generalized Dalitz
plot asymmetries in the angular distribution. These new kind of asymmetries are
constructed by adding B and ${\bar B}$ events, and do not require flavor or
time tagging, nor is the presence of strong phases needed. Using this method
one requires about $2 \times 10^8/\eta$ B's to measure the CP violating
parameter $\eta$ in the Standard model. The two--Higgs doublet model requires
only $10^7$ B's to constrain parameters better than done by the electric dipole
moment of the neutron.


title: Lightest MSSM Higgs Boson Production and its Two-Photon Decay at the LHC

abstract:
  We present an analysis of the production and two-photon decay of the lightest
CP-even Higgs boson of the Minimal Supersymmetric Standard Model (MSSM) at the
Large Hadron Collider (LHC). A rather general model is considered, without
supergravity constraints. All parameters of the model are taken into account,
we especially study the dependence of the cross section on the squark masses,
on the bilinear parameter $\mu$ and the trilinear supersymmetry breaking
parameter $A$. Non-zero values of these parameters lead to significant mixing
in the squark sector, and, thus, affect the masses of Higgs bosons through
radiative corrections, as well as their couplings to squarks. The cross section
times the two-photon branching ratio of $h^0$ is of the order of 15--25~fb in
much of the parameter space that remains after imposing the present
experimental constraints on the parameters.


title: On the possibility of the dual Meissner effect induced by instantons

abstract:
  The classical Yang-Mills equation of motion is numerically investigated in
the Lorentz gauge for a SU(2) gauge group. The color-electric field of two
point-like charges is studied in the ''empty'' vacuum and in a state with an
instanton present. The major effect for a fixed orientation of the instanton is
that the color-electric field lines are expelled or attracted from the
instanton region depending on the orientation of the instanton. If over the
orientations of the instanton is averaged, this effect drops out. In this case
of a random instanton orientation, we find that the external color-electric
field is expelled from the instanton core. The origin of this effect is
discussed.


title: How to find a Higgs Boson with a Mass between 155--180 GeV at the LHC

abstract:
  We reconsider the signature of events with two charged leptons and missing
energy as a signal for the detection of the Standard Model Higgs boson in the
mass region M(Higgs)=155--180 GeV. It is shown that a few simple experimental
criteria allow to distinguish events originating from the Higgs boson decaying
to H --> W+W- from the non resonant production of W+W- X at the LHC. With this
set of cuts, signal to background ratios of about one to one are obtained,
allowing a 5--10 sigma detection with about 5~fb-1 of luminosity. This
corresponds to less than one year of running at the initial lower luminosity L=
10**33/ cm**2/sec. This is significantly better than for the hitherto
considered Higgs detection mode H --> Z Z* --> l+ l+ l- l-, where in this mass
range about 100~fb-1 of integrated luminosity are required for a 5 sigma
signal.


title:
Correlator of the quark scalar currents and \Gamma_{tot}(H --> hadrons)
  at O(\alpha_s^3) in pQCD

abstract:
  We present the results of the analytical evaluation of the massless four-loop
O(alpha_s^3) correction to the correlator of the quark scalar currents and the
Higgs decay rate into hadrons.


title: Evading the cosmological domain wall problem

abstract:
  Discrete symmetries are commonplace in field theoretical models but pose a
severe problem for cosmology since they lead to the formation of domain walls
during spontaneous symmetry breaking in the early universe. However if one of
the vacuua is favoured over the others, either energetically, or because of
initial conditions, it will eventually come to dominate the universe. Using
numerical methods, we study the evolution of the domain wall network for a
variety of field configurations in two and three dimensions and quantify the
rate at which the walls disappear. Good agreement is found with a recent
analytic estimate of the termination of the scaling regime of the wall network.


title: Custodial Symmetry and the Triviality Bound on the Higgs Mass

abstract:
  The triviality of the scalar sector of the standard one-doublet Higgs model
implies that it is only an effective low-energy theory valid below some cut-off
scale $\Lambda$. In this note we show that the experimental constraint on the
amount of custodial symmetry violation, $|\Delta \rho_* | = \alpha |T | \le
0.4\%$, implies that the scale $\Lambda$ must be greater than of order 7.5 TeV.
For theories defined about the infrared-stable Gaussian fixed-point, we
estimate that this lower bound on $\Lambda$ yields an upper bound of
approximately 550 GeV on the Higgs boson's mass, independent of the regulator
chosen to define the theory. We also show that some regulator schemes, such as
higher-derivative regulators, used to define the theory about a different
fixed-point are particularly dangerous because an infinite number of
custodial-isospin-violating operators become relevant.


title: Constraining 2HDM by Present and Future Muon(g-2) Data

abstract:
  Constraints on the general 2HDM ("Model II") are obtained from the existing
$(g-2)_{\mu}$ data including limits on Higgs bosons masses from LEP I data. We
consider separately two cases: with a light scalar $h$ and with a light
pseudoscalar $A$, assuming ${M_{h}+M_{A}} \ge {M_{Z}}$. The charged Higgs
contribution is also included. It is found that already the present
$(g-2)_{\mu}$ data improve limits obtained recently by ALEPH collaboration on
$\tb$ for the mass of the pseudoscalar below $ \mr$ 2 GeV. The improvement in
the accuracy by factor 20 in the forthcoming E821 experiment may lead to more
stringent, than provided by ALEPH group, limits up to $M_A\sim$ 30 GeV if the
mass difference between $h$ and $A$ is $\sim M_Z$. Similar results should hold
for a light scalar scenario as well.


title:
Radiative energy loss and $p_{\perp}$-broadening of high energy partons
  in nuclei

abstract:
  The medium-induced $p_{\perp}$-broadening and induced gluon radiation
spectrum of a high energy quark or gluon traversing a large nucleus is studied.
Multiple scattering of the high energy parton in the nucleus is treated in the
Glauber approximation. We show that -dE/dz, the radiative energy loss of the
parton per unit length, grows as L, the length of the nuclear matter, as does
the characteristic transverse momentum squared of the parton $p_{\perp W}^2$.
We find dE/dz = (1/8)\alpha_s N_c $p_{\perp W}^2$ holds independent of the
details of the parton-nucleon scatterings so long as L is large. Numerical
estimates suggest that $p_{\perp}$-broadening and energy loss may be
significantly enhanced in hot matter as compared to cold matter, thus making
the study of such quantities a possible signal for quark-gluon plasma
formation.


title:
Duality Constraints on Supersymmetric Unified Models and Radiative
  Symmetry Breaking

abstract:
  Motivated from unified models with string origin, we analyse the constraints
from duality invariance on effective supergravity models with an intermediate
gauge symmetry. Requiring vanishing vacuum energy and invariance of the
superpotential couplings, we find that modular weights of the matter and higgs
fields are subject to various constraints. In addition, the vacuum expectation
values of the higgs fields breaking the intermediate gauge group, are
determined in terms of their modular weights and the moduli. We also examine
the possibility of breaking the intermediate gauge symmetry radiatively.


title: Gauge invariant formulation of strong WW scattering

abstract:
  Models of strong $WW$ scattering in the $s$-wave can be represented in a
gauge invariant fashion by defining an effective scalar propagator that
represents the strong scattering dynamics. The $\sigma(qq \ra qqWW)$ signal may
then be computed in U-gauge from the complete set of tree amplitudes, just as
in the standard model, without using the effective $W$ approximation (EWA). The
U-gauge ``transcription'' has a wider domain of validity than the EWA, and it
provides complete distributions for the final state quanta, including
experimentally important jet distributions that cannot be obtained from the
EWA. Starting from the usual formulation in terms of unphysical Goldstone boson
scattering amplitudes, the U-gauge transcription is verified by using BRS
invariance to construct the complete set of gauge and Goldstone boson
amplitudes in $R_{\xi}$ gauge.


title: Higgs mass prediction

abstract:
  In this talk the Higgs boson effects in electroweak precision observables are
reviewed and the possibility of indirect information on the Higgs mass from
electroweak radiative corrections and precision data is discussed.


title:
$\alpha_s(m_Z)$, intermediate scales and Fermion masses in supersymmeric
  theories; two-loop results

abstract:
  One way to generate an intermediate scale being consistent with gauge
coupling unification is to add new Higgs scalars above the intermediate scale.
We classify such scenarios according to their degree of departure from minimal
supersymmetric standard model. Thereafter, we summarize the results of a
two-loop renormalization group analysis of the gauge and the Yukawa sectors of
such scenarios, and their sensitivity to the {\it input} $\alpha_3(m_Z)$. The
presence of an adjoint color octet above the intermediate scale can raise the
gauge coupling unification scale to the $string$ scale, acommodate a suitable
intermediate scale, provide a left-handed $\tau$-neutrino$ mass of the order of
few electron volts and also have the right prediction of the ratio of $m_b
/m_\tau$.


title: Winding Transitions at Finite Energy and Temperature: An O(3) Model

abstract:
  Winding number transitions in the two dimensional softly broken O(3)
nonlinear sigma model are studied at finite energy and temperature. New
periodic instanton solutions which dominate the semiclassical transition
amplitudes are found analytically at low energies, and numerically for all
energies up to the sphaleron scale. The Euclidean period beta of these finite
energy instantons increases with energy, contrary to the behavior found in the
abelian Higgs model or simple one dimensional systems. This results in a sharp
crossover from instanton dominated tunneling to sphaleron dominated thermal
activation at a certain critical temperature. Since this behavior is traceable
to the soft breaking of conformal invariance by the mass term in the sigma
model, semiclassical winding number transition amplitudes in the electroweak
theory in 3+1 dimensions should exhibit a similar sharp crossover. We argue
that this is indeed the case in the standard model for M_H < 4 M_W.


title: Technicolor Mechanisms for Single Top Production

abstract:
  We investigate the contribution of technicolor mechanisms to the production
of single top quarks at hadron colliders. We find that a promising candidate
process is gluon-gluon fusion to produce a W-boson plus technipion, with
subsequent decay of the technipion to a top quark plus a bottom quark. The
top-plus-bottom mode is the dominant one when the technipion mass is larger
than the top mass. We calculate the total cross section and the $p_{T}$
distribution for the technipion production at Tevatron and LHC energies for a
range of technipion masses, starting at 200 GeV. The decay chain of technipion
to top plus bottom quarks and then top to W plus bottom yields a final state
with two W's and two bottom quarks. We study the backgrounds to our process and
the kinematic cuts that maximize the signal to background. We report event rate
estimates for the upgraded Tevatron and the LHC.


title:
Indications from Precision Electroweak Physics Confront Theoretical
  Bounds on the Mass of the Higgs Boson

abstract:
  An updated fit to the precision electroweak data and to the direct
measurement of the top quark mass $m_t$ provides significant constraints on
$m_t$ and on the Higgs boson mass $M_H$: $m_t/\text{GeV}=172\pm 6$ and
$\log_{10}(M_H/\text{GeV})=2.16\pm 0.33$, with an error correlation $\rho=0.5$.
We integrate the $(M_H, m_t)$ probability distribution found in this analysis
over various zones of the $(M_H, m_t)$ plane defined by one-sided experimental
and theoretical bounds on the Higgs boson mass, both in the Standard Model and
in its minimal supersymmetric extension. The comparison of the cumulative
probabilities gives interesting information on the likelihood that the true
value of $M_H$ is compatible with different theoretical scenarios.


title: Light Gluino Mass and Condensate from Properties of $\eta$ and $\eta'$

abstract:
  We investigate whether known properties of the $\eta'$ meson are consistent
with its being the Goldstone boson of the spontaneously broken anomaly-free R
symmetry required in the light gluino scenario. We fit the masses and $2\gamma$
decays of the $\eta$ and $\eta'$ mesons, and also their production in radiative
$J/\psi$ decays. We find that the $\eta-\eta'$ system is well-described in the
light gluino scenario, if $m_\lambda\simeq (84-144) MeV$ and
$<{\bar\lambda}\lambda> \simeq -(0.15-0.36) GeV^3$. These values are in the
range expected when the gluino gets its mass entirely from radiative
corrections.


title: $g_{\omega\rho\pi}$ reexamined

abstract:
  The transition constant for the hadronic decay $\omega \rightarrow \rho\pi$
is investigated by means of QCD sum rules in external axial field. The obtained
value for $g_{\omega\rho\pi}$ is about 16 GeV${}^{-1}$ that is in a good
agreement with experimental data.


title: Transverse mass as a means of measuring the W width at the Tevatron

abstract:
  At the Tevatron the transverse mass is used to separate on mass shell from
off mass shell W production; and the rate of off mass shell W production gives
a measure of the W width. We look at alternative variables to see if the
separation of on and off mass shell W's can be improved, and hence give a
better measure of the W width. We find that the transverse mass is very close
to the optimal variable for separating on from off mass shell W decay, and
hence there is little to be gained by using other, more complicated, variables.
This happens because if the transverse mass is above the W mass, the W is
guaranteed to be produced off mass shell.


title: QCD Phase Transition at high Temperature in Cosmology

abstract:
  The cosmological QCD phase transition is studied in terms of the color
confinement at finite temperature using the dual Higgs theory of QCD. The
confinement force is largely reduced at high temperature, which leads to the
swelling of hadrons. We derive analytical formulae for the surface tension and
the boundary thickness of the mixed phase from the effective potential at
$T_c$. We predict a large reduction of the glueball mass near $T_c$. We
investigate also the process of the hadron-bubble formation in the early
Universe.


title: Dual Higgs Mechanism and Nonperturbative QCD

abstract:
  We study the dual Higgs mechanism for the nonperturbative QCD. We point out
two kind of the ``see-saw'' relations between electric and magnetic sectors.
Owing to the Dirac condition $eg=4\pi$, the dual Ginzburg-Landau theory has the
asymptotic freedom nature on the gauge coupling constant $e$, where the
``walking coupling constant'' is predicted for $e$ in the infrared region. We
study also QCD-monopoles and instantons, which are two relevant topological
objects in QCD. Strong correlations between the QCD-monopole trajectory and the
topological charge are found both in the continuum theory and in the lattice
gauge theory.


title:
Recent Progress in Nonperturbative QCD Theory and Insight on
  Cosmological Phase Transition

abstract:
  The QCD phase transition at finite temperature is studied with the dual
Ginzburg-Landau theory, which is the QCD effective theory based on the dual
Higgs mechanism by QCD-monopole condensation. At high temperature, the
confinement force is largely reduced by thermal effects, which leads to the
swelling of hadrons. Simple formulae for the surface tension and the thickness
of the phase boundary are derived from the shape of the effective potential at
the critical temperature. We investigate also the process of the hadron-bubble
formation in the early Universe.


title: Natural Supergravity inflation

abstract:
  We identify a new mechanism in supergravity theories which leads to
successful inflation without any need for fine tuning. The simplest model
yields a spectrum of density fluctuations tilted away from scale-invariance and
negligible gravitational waves. We demonstrate that this is consistent with the
observed large-scale structure for a cold dark matter dominated, critical
density universe. The model can be tested through measurements of microwave
background anisotropy on small angular scales.


title: Constituent Quark Model Approach to Heavy Baryon Transitions

abstract:
  I discuss the structure of current-induced bottom baryon to charm baryon
transitions, and the structure of pion and photon transitions between heavy
charm or bottom baryons in the Heavy Quark Symmetry (HQS) limit as
$m_Q\rightarrow\infty$. By doing a spin-parity analysis I derive a general
formula which allows one to enumerate the independent HQS amplitudes in the
three types of transitions. I go on to show that use of the constituent quark
model for the light-side diquark transitions leads to a considerable reduction
in the number of independent amplitudes derived in the HQS limit. The
discussion includes the ground state $s$-wave as well as the $p$-wave heavy
baryons.


title: Diffractive DIS: back to triple-Regge phenomenology?

abstract:
  We discuss the factorization breaking effects caused by the contribution to
large rapidity gap events from DIS on secondary reggeons. Based on the
triple-Regge phenomenology of hadronic diffraction dissociation, we present
estimates for the flux and structure function of the f reggeon. The kinematical
x_Pom-beta correlation is shown to modify substantially the observed x_Pom
dependence of the diffractive structure function. The secondary reggeon and
x_Pom-beta correlation effects explain the recent H1 finding of the
factorization breaking and resolve the apparent contradiction between the
preliminary H1 results and predictions from the color dipole gBFKL approach. We
suggest further tests of predictions for diffractive DIS from the gBFKL
approach.


title:
Relevance of nucleon spin in amplitude analysis of reactions
  pi(-)p->pi(0)pi(0)n and pi(-)p->eta eta n

abstract:
  The measurements of reactions $\pi^- p \to \pi^- \pi^+ n$ and $\pi^+ n \to
\pi^+ \pi^- p$ on polarized targets at CERN found a strong dependence of pion
production amplitudes on nucleon spin. Analyses of recent measurements of
$\pi^- p \to \pi^0\pi^0 n$ reaction on unpolarized targets by GAMS
Collaboration at 38 GeV/c and BNL E852 Collaboration at 18 GeV/c use the
assumption that pion production amplitudes do not depend on nucleon spin, in
conflict with the CERN results on polarized targets. We show that measurements
of $\pi^- p \to \pi^0\pi^0 n$ and $\pi^- p \to \eta\eta n$ on unpolarized
targets can be analysed in a model independent way in terms of 4 partial-wave
intensities and 3 independent interference phases in the mass region where $S$-
and $D$-wave dominate. We also describe model-independent amplitude analysis of
$\pi^- p \to \pi^0\pi^0 n$ reaction measured on polarized target, both in the
absence and in the presence of $G$-wave amplitudes. We suggest that high
statistics measurements of reactions $\pi^- p \to \pi^0 \pi^0 n$ and $\pi^- p
\to \eta\eta n$ be made on polarized targets at Protvino IHEP and at BNL, and
that model-independent amplitude analyses of this polarized data be performed
to advance hadron spectroscopy on the level of spin dependent production
amplitudes.


title: Is the vacuum stable?

abstract:
  The experimental data, as well as theoretical considerations allow (and, in
some cases, require) the Universe at present to rest in a false vacuum, whose
approximate stability imposes constraints on the model parameters. Under very
general and mild conditions, the Universe would have ended up in the standard
vacuum even if the potential has deeper minima, provided there was a period in
which the temperature was > 1 TeV. In many cases, the zero temperature
tunneling rate is much smaller than the inverse age of the Universe. Future
experiments may reveal that the physical vacuum is not entirely stable.
Implications for the cosmological constant are discussed.


title: Comments on "Analytic and Numerical Study of Preheating Dynamics"

abstract:
  In a recent paper Boyanovsky et al (hep-ph/9608205) studied preheating for a
particular theory of the inflaton field. Although they results essentially
confirm those of the original papers on reheating after inflation, they claimed
that most of the earlier works on preheating did not take into account
backreaction of created particles, misused the Mathieu equation, and were
inconclusive about the symmetry restoration after preheating. We explain why we
cannot agree with these statements.


title:
$O(\alpha_s^2)$ corrections to polarized heavy flavour production at
  $Q^2\gg m^2$

abstract:
  We present analytic formulae for the heavy flavour coefficient functions for
polarized deep inelastic lepton-hadron scattering. The expressions are valid in
the kinematical regime $Q^2\gg m^2$ where $Q^2$ and $m^2$ stand for the masses
squared of the virtual photon and heavy quark respectively. Using these
coefficient functions we have computed the next-to-leading order $\alpha_s$
corrections to polarized charm production at HERA collider energies, where both
the electron and proton beams are polarized. We also give an estimate of these
corrections at fixed target experiments where the typical $Q^2$ values are much
smaller than at HERA.


title:
Resummed heavy quark production cross sections to next-to-leading
  logarithm

abstract:
  We study how next-to-leading logarithms modify predictions from leading
logarithmic soft-gluon resummation in the heavy quark production cross section
near threshold. Numerical results are presented for top quark production at the
Fermilab Tevatron and bottom quark production at fixed-target energies.


title: Transverse Momentum as a Measure of Colour Topologies

abstract:
  Several distinct colour flow topologies are possible in multiparton
configurations. A method is proposed to find the correct topology, based on a
minimization of the total transverse momentum of produced particles. This
method is studied for three-jet $Z^0 \to q\overline{q} g$ and four-jet $W^+W^-
\to q_1\overline{q}_2q_3\overline{q}_4$ events. It is shown how the basic
picture is smeared, especially by parton-shower activity. The method therefore
may not be sufficient on its own, but could still be a useful complement to
others, and e.g. help provide some handle on colour rearrangement effects.


title: Extracting visible $s-$channel Higgs in the lepton scattering

abstract:
  The contributions of $s-$channel Higgs in $l^+ l^- \rightarrow q \bar{q}$
processes in the general lepton collider ($l^+ l^-$ collider) within Standard
Model is studied. A new idea to extract the contribution by using the data from
both electron and future heavy-lepton colliders at same center-of-mass energy
is proposed. Deviations due to the $s-$channel Higgs contributions are analysed
and discussed for the heavy-quark final states by using the total
cross-section, forward-backward asymmetry and its ratio. It is shown that
significant deviations are expected for the top quark final state.


title:
Multiplicity Distributions in Strong Interactions: A Generalized
  Negative Binomial Model

abstract:
  A three-parameter discrete distribution is developed to describe the
multiplicity distributions observed in total- and limited phase space volumes
in different collision processes. The probability law is obtained by the
Poisson transform of the KNO scaling function derived in Polyakov's similarity
hypothesis for strong interactions as well as in perturbative QCD. Various
characteristics of the newly proposed distribution are investigated e.g. its
generating function, factorial moments, factorial cumulants. Several limiting
and special cases are discussed. A comparison is made to the multiplicity data
available in e+e- annihilations at the Z0 peak.


title: A chiral Lagrangian for excited pions

abstract:
  We construct a chiral Lagrangian containing besides the usual pion field (pi)
also its first radial excitation (pi'). The Lagrangian is derived by
bosonization of a Nambu--Jona-Lasinio quark model with separable non-local
interactions, with form factors corresponding to 3-dimensional ground and
excited state wave functions. Chiral symmetry breaking is governed by the NJL
gap equation. The effective Lagrangian for pi- and pi'-mesons shows the
decoupling of the Goldstone pion and the vanishing of the pi' leptonic decay
constant, f_pi', in the chiral limit, as required by axial current
conservation. We derive the excited states' contribution to the axial current
of the model using Noether's theorem. For finite pion mass and pi' masses in
the range of 750 MeV -- 1300 MeV, f_pi' / f_pi is found to be of the order of 1
percent.


title: Heavy Baryons and QCD Sum Rules

abstract:
  We discuss an application of QCD sum rules to the heavy baryons $\Lambda_Q$
and $\Sigma_Q$. The predictions for the masses of heavy baryons, residues and
Isgur-Wise function are presented.
  The new results on two loop anomalous dimensions of baryonic currents and QCD
radiative corrections (two- and three- loop contributions) to the first two
Wilson coefficients in OPE are explicitly presented.


title: Limits on Flavor-Universal Colorons

abstract:
  A flavor-universal extension of the strong interactions was recently proposed
in response to the apparent excess of high-$E_T$ jets in the inclusive jet
spectrum measured at the Tevatron. The color octet of massive gauge bosons
(`colorons') that is present in the low-energy spectrum of the model's Higgs
phase is studied here. Experimental constraints already imply that the coloron
mass must exceed 870-1000 GeV. The import of recent Tevatron data and the
prospective input from future experiments are also mentioned.


title: Classical Field Dynamics of the Electroweak Phase Transition

abstract:
  We investigate the thermodynamics and dynamics of the electroweak phase
transition by modelling the infrared physics with classical Yang-Mills Higgs
theory. We discuss the accuracy of this approach and conclude that, for
quantities whose determination is dominated by the infrared, the classical
method should be correct up to parametrically suppressed (ie O(alpha))
corrections. For a Higgs self-coupling which at tree level corresponds to m_H ~
50 GeV, we determine the jump in the order parameter to be delta phi = 1.5 gT,
the surface tension to be sigma = 0.07 g^4 T^3, and the friction coefficient on
the moving bubble wall due to infrared bosons to be \eta = P/v_w = 0.03 \pm
.004 g^6 T^4. We also investigate the response of Chern-Simons number to a
spatially uniform chemical potential and find that it falls off a short
distance inside the bubble wall, both in equilibrium and below the equilibrium
temperature.


title:
The Strong Coupling Constants of Excited Positive Parity Heavy Mesons in
  Light Cone QCD

abstract:
  We calculate the strong coupling constants g_(P^(**)P^(*)\pi), where
P^(**)(D^(**), B^(**)) is the 1^+ p-wave state, in the framework of the light
cone QCD sum rules, and using these values of g_(P^(**)P^(*) pi, we compute the
hadronic decay widths for D^(**) -> D^* pi and B^(**) -> B^* pi.


title:
Bounds from $t \bar t$ production on R-parity violating models of
  supersymmetry

abstract:
  We study $t \bar t$ production in R-parity violating supersymmetry. The
annihilation channel $q \bar q \rightarrow t \bar t$ gets new contributions
from $t$-channel exchange of squarks or sleptons. With the data from Tevatron
on $t \bar t$ production, we find that the squark- or slepton-exchange
processes constrain the $B$-violating $\lambda''$ couplings or the
$L$-violating $\lambda'$ couplings, respectively. Our bounds are already
comparable to the few existing constraints on third-generation $R$-parity
violating couplings, and will improve when more precise measurements of the $t
\bar t$ production cross-section become available. We also discuss the effects
of these couplings for top production at the LHC.


title: A Phenomenological Formula for KM Matrix

abstract:
  We propose a phenomenological formula relating the Kobayashi-Maskawa matrix
$V_{KM}$ and quark masses in a form $(m_d,\ m_s,\ m_b)\propto (m_u,\ m_c,\
m_t)V_{KM}$. The formula agrees with experimental data well and has an
interesting geometric picture. The origin of such a formula is discussed in the
standard model.


title: Cosmological abundances of right-handed neutrinos

abstract:
  We study the equilibration of the right-helicity states of light Dirac
neutrinos in the early universe by solving the momentum dependent Boltzmann
equations numerically. We show that the main effect is due to electroweak gauge
boson poles, which enhance thermalization rates by some three orders of
magnitude. The right-helicity states of tau neutrinos will be brought in
equilibrium independently of their initial distribution at a temperature above
the poles if the tau neutrino mass is larger than about 10 keV.


title:
Forward $\pi^0$ trigger of the deep inelastic + jet probe of BFKL
  dynamics

abstract:
  We predict the rate of deep inelastic scattering (DIS) events containing an
identified forward $\pi^0$ that is expected in the experiments at the HERA
electron-proton collider, in order to see if this process can be used as an
indicator of the underlying small $x$ dynamics. We determine the background due
to deep inelastic events containing forward photons which are fragments of the
forward jet. We compare the DIS + $\pi^0$ cross section with that of the DIS +
parent jet process.


title: Higher-order corrections in the SM Higgs sector: the right scale

abstract:
  The evaluation of high-energy cross sections involving the SM Higgs boson
requires the use of the Higgs running coupling $\lambda(\mu)$. Taking $\mu$ to
be equal to the center-of-mass energy $\sqrt{s}$ of the scattering process, the
perturbative approach fails for relatively small values of the Higgs mass and
coupling, $\lambda(\sqrt{s})\approx 2.2$. Performing an approximate resummation
of ``bubble'' Feynman diagrams, we find the scale $\mu=\sqrt{s}/ e \approx
\sqrt{s}/2.7$ to yield reliable perturbative results, even for large Higgs mass
and coupling. The new perturbative upper limit on the Higgs running coupling is
$\lambda(\sqrt{s}/ e)\approx 4$.


title:
Explicit CP Violation in the Higgs Sector of the Next-to-Minimal
  Supersymmetric Standard Model

abstract:
  We analyze explicit CP violation in the Higgs sector of the next-to-minimal
supersymmetric standard model which contains an additional gauge singlet field
N. It is shown that there is no mixing among scalar and pseudoscalar Higgs
fields in the two Higgs doublets, and scalar-pseudoscalar mixings could exist
between two Higgs doublets and the singlet N, and between N itself. CP symmetry
is conserved in the extreme limits of < N > >> v, < N > << v, and tan beta >>
1. In the region of < N > = O(v) and tan beta = O(1), large scalar-pseudoscalar
mixings are realized, and this effect can reduce the lightest Higgs mass. The
mass difference between no mixing and mixing case is about 10 - 30 GeV. The
neutron electric dipole moment in this model is consistent with the present
experimental upper limit provided that squark and gaugino masses are heavy
enough of O(1) TeV.


title: CP Violation and Baryogenesis at the Electroweak Phase Transition

abstract:
  We report a recent attempt to relate $CP$ violation in the electroweak theory
with two Higgs doublets to the baryon asymmetry generated at the electroweak
phase transition, after surveying the scenario of the electroweak baryogenesis.


title: Natural New Inflation in Broken Supergravity

abstract:
  We consider a natural new inflationary model in broken supergravity based on
an R symmetry. The model predicts a concrete relation between the amplitude of
primordial density fluctuations and the scale of supersymmetry breaking. The
observed value of the density fluctuations is obtained for the gravitino mass
of order the weak scale along with a power-law spectral index considerably less
than one, which may be tested in future observations.


title: Perturbative description of inclusive energy spectra

abstract:
  The recent LEP-1.5 data on charged particle inclusive energy spectra are
analyzed within the analytical QCD approach based on Modified Leading Log
Approximation plus Local Parton Hadron Duality. The shape, the position of the
maximum and the cumulants moments of the inclusive energy spectrum are well
described within this model. The sensitivity of the results to the running of
the coupling is pointed out. A scaling law for the one-particle invariant
density $E dn/d^3p$ at small momenta is observed, consistently with the
predictions of colour coherence in soft gluon bremsstrahlung.


title: CP Violation in the Decay B \to X_d e^+ e^-

abstract:
  The decay $b\to d e^+e^-$ has an amplitude containing comparable
contributions proportional to $V_{tb}V_{td}^{*}$, $V_{cb}V_{cd}^{*}$ and
$V_{ub}V_{ud}^{*}$. These pieces involve different unitarity phases produced by
$c\bar{c}$ and $u\bar{u}$ loops. The simultaneous presence of different CKM
phases and different dynamical phases leads to a calculable asymmetry in the
partial widths of $b\to d e^+e^-$ and $\bar{b}\to \bar{d} e^+e^-$. Using the
effective Hamiltonian of the standard model, we calculate this asymmetry as a
function of the $e^+e^-$ invariant mass. The effects of $\rho$, $\omega$ and
$J/\psi$ resonances are taken into account in the vacuum polarization of the
$u\bar{u}$ and $c\bar{c}$ currents. As a typical result, an asymmetry of $- 5%
(- 2%)$ is predicted in the nonresonant domain $1 GeV < m_{e^+e^-} <
m_{J/\psi}$, assuming $\eta = 0.34$ and $\rho= 0.3 (-0.3)$. The branching ratio
in this domain is $1.2\times 10^{-7} (3.3\times 10^{-7})$. Results are also
obtained in the region of the $J/\psi$ resonance, where an asymmetry of
$3\times 10^{-3}$ is expected, subject to certain theoretical uncertainties in
the $b\to d J/\psi$ amplitude.


title: New developments in the theory of heavy quarkonia

abstract:
  The new approach to decays of heavy quarkonia, based on factorization and
expansions in powers of the relative velocity of the valence quarks is
reviewed.


title:
The masses of vector supermultiplet and of the Higgs supertriplet in
  supersymmetric SU(5) model

abstract:
  The masses of vector supermultiplet and of the Higgs supertriplet in standard
supersymmetric SU(5) model are calculated. Taking into account uncertainties
related with the initial coupling constants and threshold corrections we find
that in supersymmetric SU(5) model the scale of the supersymmetry breaking
could be up to 50 Tev. We find that in the extensions of the standard SU(5)
supersymmetric model it is possible to increase the supersymmetry breaking
scale up to $O(10^{12})$ Gev. In standard supersymmetric SU(5) model it is
possible to increase the GUT scale up to $5 \cdot 10^{17}$ Gev provided that
the masses of chiral superoctets and supertriplets are $m_{3,8} \sim O(10^{13})
Gev$. We also propose SU(5) supersymmetric model with 6 light superdoublets and
superoctet with a mass $O(10^{9})$ Gev.


title:
CP Violation Beyond the Standard Model and Tau Pair Production in $e^+
  e^-$ Collisions

abstract:
  We show that the CP-violating dipole form factors of the tau lepton can be of
the order of $\alpha/\pi$ in units of the length scale set by the inverse $Z$
boson mass. We propose a few observables which are sensitive to these form
factors at LEP2 and higher e^+e^- collision energies.


title: A 1996 Analysis of the CP Violating Ratio epsilon'/epsilon

abstract:
  We update our 1993 analysis of the CP violating ratio $\epe$ in view of the
changes in several input parameters, in particular the improved value of the
top quark mass. We also investigate the strange quark mass $m_s$ dependence of
$\epe$ in view of rather low values found in the most recent lattice
calculations. A simple scanning of the input parameters within one standard
deviation gives the ranges: $-1.2 \cdot 10^{-4} \le \epe \le 16.0 \cdot
10^{-4}$ and $0 \le \epe \le 43.0 \cdot 10^{-4}$ for $\ms(\mc)=150\pm20~ \mev$
and $\ms(\mc)=100\pm20~ \mev$ respectively. If the experimentally measured
numbers and the theoretical input parameters are used with Gaussian errors, we
find $\epe= ( 3.6\pm 3.4) \cdot 10^{-4}$ and $\epe= ( 10.4\pm 8.3) \cdot
10^{-4}$ respectively. We also give results for ${\rm Im} V_{ts}^*V_{td}$.
Analyzing the dependence of $\epe$ on various parameters we find that only for
$\ms(\mc)\le 100\,\mev$ and a conspiration of other input parameters, values
for $\epe$ as large as $(2-4) \cdot 10^{-3}$ and consistent with the NA31
result can be obtained.


title:
Nonfactorizable QCD and Electroweak Corrections to the Hadronic Z Boson
  Decay Rate

abstract:
  We present an analysis of two-loop mixed QCD and electroweak corrections to
the decay of the Z boson into light quarks. We find that the naive
factorization of QCD and electroweak corrections does not describe correctly
the two-loop effects. The nonfactorizable corrections shift the width of the Z
boson by approximately -0.55(3) MeV and increase the central value of the
strong coupling constant determined at LEP by 0.001.


title: LEP2 physics and event generators

abstract:
  The present status of four-fermion calculations and event generators for LEP2
physics is reviewed. Perspectives for future improvements are given.


title:
Leptoquark Mass Limits from Single Leptoquark Production at LEP and
  LEP200

abstract:
  We investigate the discovery potential for first generation leptoquarks at
the LEP and LEP200 $e^+e^-$ colliders. We consider single leptoquark production
via resolved photon contributions which offers a much higher kinematic limit
than the more commonly considered leptoquark pair production process. This
process also has the advantage that it is independent of the leptoquark
chirality, is almost insensitive to whether the leptoquark is scalar or vector,
and only depends on the leptoquark charge. We estimate that from the
nonobservation of energetic $e-jet$ events, the limits at LEP for all types of
leptoquarks are $M_{LQ} > 90$~GeV. For the just completed $\sqrt{s}=161$~GeV
run at LEP200 we estimate potential scalar leptoquark mass limits of $M_{LQ} >
130$~GeV for $Q_{LQ}=-2/3, \; -4/3$ and $M_{LQ} > 148$~GeV for $Q_{LQ}=-1/3, \;
-5/3$ and for vector LQ's the limits are 140 and 154~GeV respectively.
Ultimately, LEP200 should be able to achieve discovery limits for leptoquarks
of $\sim 188$~GeV for the $\sqrt{s}=190$~GeV runs. In all cases we assume
electromagnetic strength coupling.


title: On the $Q^2$ Dependence of Asymmetry $A_1$

abstract:
  We analyse the proton and deutron data on spin dependent asymmetry
$A_1(x,Q^2)$ supposing the DIS structure functions $g_1(x,Q^2)$ and
$F_3(x,Q^2)$ have the similar $Q^2$-dependence.


title: Charmonium Production in High Energy Collisions

abstract:
  In recent years, there have been significant developments in heavy quarkonium
production, both in theory and in experiment. These developments may have
important implications for the use of charmonium as a probe in heavy-ion
collisions. A summary of these developments is presented below. Those
interested in more details are referred to a recent review article by Braaten,
Fleming, and Yuan.


title: Strong WW Scattering. Chiral Lagrangians, Unitarity and Resonances

abstract:
  Chiral lagrangians provide a model independent description of the strongly
interacting symmetry breaking sector. In this work it is first reviewed the LHC
sensitivity to the chiral parameters (in the hardest case of non-resonant
low-energy WW scattering). Later it is shown how to reproduce or predict the
resonance spectrum by means of dispersion theory and the inverse amplitude
method. We present a parameter space scan that covers many different strong WW
scattering scenarios.


title:
A Non-Minimal SO(10) x U(1)_F SUSY - GUT Model Obtained from a Bottom-Up
  Approach

abstract:
  Many of the ingredients are explored which are needed to develop a super-
symmetric SO(10) x U(1)_F grand unified model based on the Yukawa structure of
a model previously constructed in collaboration with S. Nandi to explain the
quark and lepton masses and mixings in a particular neutrino scenario. The
U(1)_F family symmetry can be made anomaly-free with the introduction of one
conjugate pair of SO(10)-singlet neutrinos with the same U(1)_F charge. Due to
a plethora of conjugate pairs of supermultiplets, the model develops a Landau
singularity within a factor of 1.5 above the GUT scale. With the imposition of
a Z_2 discrete symmetry and under certain conditions, all higgsino triplets can
be made superheavy while just one pair of higgsino doublets remains light and
results in mass matrix textures previously obtained from the bottom-up
approach. Diametrically opposite splitting of the first and third family scalar
quark and lepton masses away from the second family ones results from the
nonuniversal D-term contributions.


title: The axial anomaly in QCD at finite temperature

abstract:
  We study flavor mixing and the axial anomaly in QCD at zero and finite
temperature. Using the instanton liquid model, we show that the strength of the
anomaly is essentially unchanged near the critical temperature for chiral
symmetry restoration. We demonstrate that nevertheless, chiral symmetry
restoration has important consequences for the eta and eta prime. In
particular, the strange and non-strange components of the eta unmix near T_c.
The anomaly does not affect the strange eta, so we expect a light purely
strange pseudoscalar meson near the phase transition.


title: Quantum System under Periodic Perturbation: Effect of Environment

abstract:
  In many physical situations the behavior of a quantum system is affected by
interaction with a larger environment. We develop, using the method of
influence functional, how to deduce the density matrix of the quantum system
incorporating the effect of environment. After introducing characterization of
the environment by spectral weight, we first devise schemes to approximate the
spectral weight, and then a perturbation method in field theory models, in
order to approximately describe the environment. All of these approximate
models may be classified as extended Ohmic models of dissipation whose
differences are in the high frequency part.
  The quantum system we deal with in the present work is a general class of
harmonic oscillators with arbitrary time dependent frequency. The late time
behavior of the system is well described by an approximation that employs a
localized friction in the dissipative part of the correlation function
appearing in the influence functional. The density matrix of the quantum system
is then determined in terms of a single classical solution obtained with the
time dependent frequency. With this one can compute the entropy, the energy
distribution function, and other physical quantities of the system in a closed
form.
  Specific application is made to the case of periodically varying frequency.
This dynamical system has a remarkable property when the environmental
interaction is switched off: Effect of the parametric resonance gives rise to
an exponential growth of the populated number in higher excitation levels, or
particle production in field theory models. The effect of the environment is
investigated for this dynamical system and it is demonstrated that there exists


title: Fixed points and power corrections

abstract:
  The connection between renormalons and power corrections is discussed in the
case the effective coupling constant has an infrared fixed point of
perturbative origin.


title:
Top quark loop corrections to the decay $H^+ \to h^0 W^+$ in the Two
  Higgs Doublet Model

abstract:
  We calculate the decay width for the process $H^+ \to h^0 W^+$ up to order
$g^4$ in the framework of the Two Higgs Doublet Model. We argue that for some
reasonable choice of the free parameters the contribution from the one-loop
graphs can be as large as 40%.


title: Mass effects in a Three-Body System Bound by Harmonic Oscilators

abstract:
  The problem of three different masses bound by harmonic oscillator potentials
is solved exactly. It is shown that Jacobi coordinates cannot, in general,
decouple this system into two three-dimensional oscillators but this decoupling
can always be obtained in terms of the normal coordinates. The condition for
the decoupling in Jacobi coordinates is given. It is shown that the mean
distance between each pair of particles depends upon their masses.


title: Photoproduction of jets at NLO

abstract:
  A new next-to-leading order Monte Carlo program for the calculation of fully
differential jet cross sections in photoproduction is described. The
contributions from both resolved and direct components are included. A
comparison between the theoretical predictions and ZEUS data is presented.


title: Electroproduction of heavy quarks at NLO

abstract:
  A new next-to-leading order Monte Carlo program for the calculation of fully
differential heavy quark cross sections in electroproduction is described. A
comparison between the theoretical predictions and the latest charm production
data from H1 and ZEUS at HERA is presented.


title: Confinement in Light-Front QCD

abstract:
  Numerical results for the calculation of the (rest-frame) $Q\bar{Q}$
potential, for light-front quantized $QCD_{2+1}$ on a $\perp$ lattice are
presented. Both in the longitudinal as well as the $\perp$ spatial directions
one obtains linear confinement. The resulting potential is almost rotational
symmetric.


title: High-Temperature Thermodynamics of QCD

abstract:
  Effective-field-theory methods are used to study the high T limit of QCD.
These methods unravel the contributions to the free energy of QCD at high
temperature from the scales T, gT, and g^2 T. The free energy is explicitly
computed to order g^5. Implications for the application of perturbative QCD to
the quark-gluon plasma are also discussed.


title: Definition of $\tan\beta$ beyond tree-level

abstract:
  We study the relation between different renormalization schemes for the
parameter $\tan\beta$ in the Minimal Supersymmetric Standard Model. The
contributions of the third-generation quark-squark loops to the differences
between $\tan\beta$'s in several schemes are discussed. Their numerical
differences are typically within several %.


title:
Parity Violation in Bottom Quark Pair Production at Polarized Hadron
  Colliders

abstract:
  Parity violation induced by the chromo-anapole form factor of the bottom
quark, generated from weak corrections, is studied in polarized hadron
collisions. The forward-backward asymmetry in the bottom quark pair production
at polarized $pp$ and $p\bar{p}$ colliders is evaluated in the Standard Model
and in a Two Higgs Doublet Model to examine the effects of parity violation. In
the models studied, promising results are found for polarized $p\bar{p}$
colliders.


title: Regge Pole Model for Vector Meson Photoproduction at HERA

abstract:
  Recent $HERA$ data on the photoproduction of vector mesons are analysed
within a "soft", dipole pomeron model. We argued that the data on
$\sigma^{\gamma\rightarrow J/\psi}_{el}$ is consistent with a soft pomeron, the
apparent rapid increase resulting from the non-asymptotic effects due to the
delayed asymptotics of $\sigma_{el}$ with respect to $\sigma_{tot}$.


title: The decay constants of pseudoscalar mesons in a relativistic quark model

abstract:
  The decay constants of pseudoscalar mesons are calculated in a relativistic
quark model which assumes that mesons are made of a valence quark antiquark
pair and of an effective vacuum like component. The results are given in terms
of quark masses and of some free parameters entering the expression of the
internal wave functions of the mesons. By using the pion and kaon decay
constants $F_{\pi^+}=130.7~MeV,~F_{K^+}=159.8~MeV$ to fix the parameters of the
model one gets $60~MeV\leq F_{D^+}\leq 185~MeV,~95~MeV\leq
F_{D_s}\leq230~MeV,~80~MeV\leq F_{B^+}\leq205~MeV$ for the light quark masses
$m_u=5.1~MeV,~m_d=9.3~MeV,~m_s=175~MeV$ and the heavy quark masses in the
range: $1.~GeV\leq m_c\leq1.6~GeV,~4.1~GeV\leq m_b\leq4.5~GeV$. In the case of
light neutral mesons one obtains with the same set of parameters
$F_{\pi^0}\approx 138~MeV,~F_\eta\approx~130~MeV,F_{\eta'} \approx~78~MeV$. The
values are in agreement with the experimental data and other theoretical
results.


title: Proton Diffraction Dissociation and Unitarity

abstract:
  It is shown that the dipole pomeron model of single diffraction dissociation
-- contrary to the case of the supercritical pomeron -- is compatible with the
inequality $\sigma^{SD}\leq\sigma^{tot}$, imposed by unitarity, provided the
triple pomeron coupling satisfies certain conditions. With the adopted
approximation the model considered as a parcticular solution of the triple
pomeron decoupling problem. Explicit forms of such a coupling and a qualitative
comparison with the experimental data on single DD are presented. The modified
factorization properties of the model are also discussed.


title: Phenomenology of Charginos and Neutralinos in the Light Gaugino Scenario

abstract:
  The light gaugino scenario predicts that the lighter chargino mass is less
than m_W, gluino and lightest neutralino masses are <~ 1 GeV, and the dominant
decay mode of charginos and non-LSP neutralinos is generically to three jets.
The excess "4j" events observed by ALEPH in e+ e- annihilation at 133 GeV may
be evidence that m(C_1) = 53 GeV. If so, m(N_2) = 110-121 GeV, m(N_2) = 38-63
GeV, m(N_3) = 75-68 GeV; m(sneu_e) is probably ~m(C_1). A detailed analysis of
the multi-jet events is needed to exclude this possibility. Consequences for
FNAL and higher energy LEP running are given.


title: Color-octet mechanism in J/psi productions

abstract:
  I review recent developments in theoretical understandings of J/psi
productions in various processes at Tevatron, B decay and J/psi photoproduction
including the color-octet mechanism.


title: Determination of the HQET Parameters from the $B \to X_s\gamma$ Decay

abstract:
  We combine the resummations for radiative corrections and for the heavy quark
expansion to study the inclusive radiative decay $B \to X_s\gamma$. The
infrared renormalon ambiguity is also taken into account. Including both
theoretical and experimental uncertainties, we determine the allowed domain for
the HQET parameters ${\bar \Lambda}$ and $\lambda_1$ centered at ${\bar
\Lambda}=0.65$ GeV and $\lambda_1=-0.71$ GeV$^2$.


title: Defects in Modified Axial Gauge QCD_{3+1}

abstract:
  Magnetically charged vortex defects are shown to arise in canonically
quantised modified axial gauge QCD_{3+1} on a torus. This gauge -- being an
Abelian projection -- keeps only the eigenphases as dynamical variables of the
Wilson line in x_3-direction. A mismatch between the identification of large
gauge transformations before and after gauge fixing is indicated.


title: Diffraction in DIS on nuclear targets

abstract:
  We discuss the implications of a strong enhancement of diffraction for
multiproduction in DIS off nuclear targets. The predicted effects are large and
observable at HERA. We present the prediction of a large tensor structure
function b_2(x) of the deuteron which does not vanish at small x.


title: Average Kinetic Energy of Heavy Quark and Virial Theorem

abstract:
  We derive the virial theorem of the relativistic two-body system for the
study of the B-meson physics. It is also shown that the solution of the
variational equation always satisfies the virial theorem. From the virial
theorem we also obtained $\mu_\pi^2 \equiv -\lambda_1 \equiv < p^2> = 0.40\sim
0.58$ GeV$^2$, which is consistent with the result of the QCD sum rule
calculations of Ball $et$ $al.$


title: On the Physics Potential of Polarized Nucleon-Nucleon Collisions at HERA

abstract:
  The physics of polarized nucleon--nucleon collisions originating from an
internal polarized target in the HERA proton beam is investigated. Based on 240
pb^-1 integrated luminosity at 40 GeV c.m. energy, statistical sensitivities
are given over a wide (x_F, p_T) range for a variety of inclusive and exclusive
final states. By measuring single spin asymmetries unique information can be
obtained on higher twist contributions and their p_T-dependence. From double
spin asymmetries in both photon and J/psi production it appears possible to
measure the polarized gluon distribution in the range 0.1<x_gluon<0.4 with a
good statistical accuracy.


title: Power Corrections and Renormalons in $e^+e^-$ Fragmentation Functions

abstract:
  We estimate the power corrections (infrared renormalon contributions) to the
coefficient functions for the transverse, longitudinal and asymmetric
fragmentation functions in $e^+e^-$ annihilation, using a method based on the
analysis of one-loop Feynman graphs containing a massive gluon. The leading
corrections have the expected $1/Q^2$ behaviour, but the gluonic coefficients
of the longitudinal and transverse contributions separately have strong
singularities at small $x$, which cancel in their sum. This leads to $1/Q$
corrections to the longitudinal and transverse parts of the annihilation cross
section, which cancel in the total cross section.


title: SU(3) Symmetry Breaking and Octet Baryon Polarizabilities

abstract:
  Static polarizabilities of the low--lying $1/2^+$ baryons are studied within
the collective coordinate approach to the three flavor generalization of the
Skyrme model; in particular, magnetic polarizabilities are considered.
Predicted polarizabilities, which result from different treatments of the
strange degrees of freedom in this model, are critically compared. Their
deviations from the flavor symmetric formulations are discussed.


title: Pions at Finite Temperature from QCD Sum Rules

abstract:
  The temperature corrections to the current algebra Gell-Mann, Oakes, and
Renner (GMOR) relation in $SU(2)\otimes SU(2)$ are investigated in the
framework of QCD sum rules. There are no corrections at leading order in the
quark masses. At the next to leading order we find corrections of the form
$m_{q}^2\; T^{2}$, which are small except near the critical temperature. As a
by-product we obtain the temperature behaviour of the pion mass, which is
essentially constant, except near the critical temperature where it increases
with $T$.


title: Form factors of the nucleon in the SU(3) chiral quark-soliton model

abstract:
  The recent investigation on various form factors of the nucleon is reviewed
in the framework of the SU(3) chiral quark-soliton model. The results for the
electromagnetic and scalar form factors are in remarkable agreement with
experimental and empirical data. The strange vector form factors are also
discussed with the effect of the kaon cloud being considered. In addition to
the form factors, the recent calculation of the tensor charges is presented.


title: Tree-Level Nondecoupling and the Supersymmetric Higgs Sector

abstract:
  Because of the existence of cubic scalar couplings, there are in general
nondecoupling effects at tree level in the scalar sector of any theory with two
or more very different mass scales. We show this explicitly in the minimal
nonsupersymmetric SU(5) model of grand unification. We show also how tree-level
decoupling is guaranteed if supersymmetry is imposed. On the other hand, if the
gauge symmetry is larger than that of the standard model at the mass scale of
supersymmetry breaking, the two-Higgs-doublet structure at the presumably lower
electroweak energy scale will be different from that of the minimal
supersymmetric standard model, as shown already previuosly in a number od
specific examples. We add here one example involving four Higgs doublets.


title: Polarized Partons at Next-to-Leading Order

abstract:
  We discuss the determination of polarized parton distributions from a
next-to-leading order analysis of recent experimental data. We extract the
first moment of the polarized quark and gluon distribution and assess the
corresponding uncertainties, with special regard to those related to scheme
dependence.


title: A Short Review and Some New Results on Polarization

abstract:
  I present the highlights of a long review on polarization in deep inelastic
scattering. Some new results are discussed at the end of the talk.


title:
The $\gamma^*\gamma^*$ Total Cross Section and the BFKL Pomeron at
  $e^{+}e^{-}$ Collider

abstract:
  We present a numerical estimate of the $\gamma^* \gamma^*$ total cross
section at LEP and at the designed $e^+e^-$ Next Linear Collider (NLC), based
upon the BFKL Pomeron. We find for the linear collider that the event rate is
substantial provided electrons scattered under small angles can be detected,
and a measurement of this cross section provides an excellent test of the BFKL
Pomeron. For LEP, although the number of events is substantially smaller, an
initial study of this process is feasible.


title:
Running Coupling Constant of a Gauge Theory in the Framework of the
  Schwinger-Dyson Equation: Infrared Behavior of Three-Dimensional Quantum
  Electrodynamics

abstract:
  We discuss how to define and obtain the running coupling of a gauge theory in
the approach of the Schwinger-Dyson equation, in order to perform a
non-perturbative study of the theory. For this purpose, we introduce the
nonlocally generalized gauge fixing into the SD equation, which is used to
define the running coupling constant (this method is applicable only to a gauge
theory). Some advantages and validity of this approach are exemplified in QED3.
This confirms the slowing down of the rate of decrease of the running coupling
and the existence of non-trivial infra-red fixed point (in the normal phase) of
QED3, claimed recently by Aitchison and Mavromatos, without so many of their
approximations. We also argue that the conventional approach is recovered by
applying the (inverse) Landau-Khalatnikov transformation to the nonlocal gauge
result.


title: Strong $U_A(1)$ breaking in radiative $\eta$ decays

abstract:
  We study the \egg, \egm and \epg decays using an extended three-flavor
Nambu-Jona-Lasinio model that includes the 't~Hooft instanton induced
interaction. We find that the $\eta$-meson mass, the \egg, \egm and \epg decay
widths are in good agreement with the experimental values when the $U_{A}(1)$
breaking is strong and the flavor $SU(3)$ singlet-octet mixing angle $\theta$
is about zero. The calculated $\eta \gamma \gamma^\ast$ transition form factor
has somewhat weaker dependence on the squared four-momentum of the virtual
photon. The effects of the $U_A(1)$ anomaly on the scalar quark contents in the
nucleon, the $\Sigma_{\pi N}$ and $\Sigma_{KN}$ terms and the baryon number one
and two systems are also studied.


title:
The Unitarity Triangle on the First Quadrant and the Quark Mass Matrices
  in the Nearest-Neighbor Interaction Basis

abstract:
  The unitarity triangle on the first quadrant in the $\rho -\eta$ plane is
discussed in the framework of the quark mass matrices in the NNI basis. If the
quark mass matrices of the up-type is the Fritzsch one and the down-type is the
one proposed by Branco et al., respectively, one gets the unitarity triangle
with the vertex on the first quadrant. This simple model may be a candidate of
the quark mass matrix ansatze, if the allowed region of the vertex of the
unitarity triangle is restricted in the first quadrant by future experiments.


title: Cosmological Axion Problem in Chaotic Inflationary Universe

abstract:
  We investigate two cosmological axion problems (isocurvature fluctuations and
domain-wall formation) in chaotic inflationary universe. It is believed that
these problems are solved if potential for the Peccei-Quinn scalar field is
very flat. However, we find that too many domain walls are produced through
parametric resonance decay of the Peccei-Quinn scalar field. Only the axion
model with N=1(N: QCD anomaly factor) is consistent with observations. We also
point out that the flat potential is naturally obtained in a supersymmetric
extension of the Peccei-Quinn model. If Peccei-Quinn breaking scale $F_a$ is
about 10^{12} GeV, this model predicts anisotropies of cosmic microwave
background radiation due to the axion isocurvature fluctuations which may be
detectable in future observations.


title:
Heavy Quark Kinetic Energy in B Mesons by a QCD Relativistic Potential
  Model

abstract:
  The matrix element of the kinetic energy operator between B meson states is
computed by means of a QCD relativistic potential model, with the result:
$\mu_\pi^2=0.66 GeV^2$. A comparison with the outcome of other theoretical
approaches and a discussion of the phenomenological implications of this result
are carried out.


title: Threshold behavior of Feynman diagrams: the master two-loop propagator

abstract:
  An asymptotic expansion of the two-loop two-point ``master'' diagram with two
masses $m$ and $M$, on the mass shell $Q^2=M^2$, is presented. The treatment of
the non-analytical terms arising in the expansion around the branching point is
discussed. Some details of the calculation of a new class of two-loop integrals
are given.


title:
Photoproduction of Jets and Heavy Flavors in Polarized ep - Collisions
  at HERA

abstract:
  We study photoproduction of jets and heavy flavors in a polarized collider
mode of HERA at $\sqrt{S}= 298$ GeV. We examine the sensitivity of the cross
sections and their asymmetries to the proton's polarized gluon distribution and
to the completely unknown parton distributions of longitudinally polarized
photons.


title: The Longitudinal Structure Function $F_L$ at small x

abstract:
  We present a set of formulae to extract the longitudinal deep inelastic
structure function $F_L$ from the transverse structure function $F_2$ and its
derivative $dF_2/dlnQ^2$ at small $x$. Using $F_2$ HERA data we obtain $F_L$ in
the range $10^{-4} \leq x \leq 10^{-2}$ at $Q^2=20$ GeV$^2$


title: Hard thermal loops near the light-cone

abstract:
  In hot gauge theories, perturbation theory at the scale of the Debye
screening mass requires the resummation of the so-called hard thermal loops,
which corresponds to using an effective action obtained by integrating out the
modes with momentum of order of the temperature. As is well-known, quantities
which are sensitive to the nonperturbative magnetic screening mass still remain
incalculable in this resummed perturbation theory. A different breakdown of the
latter occurs whenever external momenta are light-like, because the hard
thermal loops themselves develop collinear singularities. However, taking into
account asymptotic thermal masses for the hard modes regulates the hard thermal
loops without spoiling their gauge invariance.


title: DIS96 - Summary

abstract:
  Some of the new experimental results and theoretical developments presented
at the Workshop on Deep Inelastic Scattering and Related Phenomena (Rome, April
1996) are reviewed.


title:
BHWIDE 1.00: O(alpha) YFS Exponentiated Monte Carlo for Bhabha
  Scattering at Wide Angles for LEP1/SLC and LEP2

abstract:
  We present O(alpha) YFS exponentiated results for wide angle Bhabha
scattering at LEP/SLC energies using a new Monte Carlo event generator BHWIDE
1.xx. Our calculations include two options for the pure weak corrections, as
presented in Beenakker et al. and in Bohm et al. From comparison with the
results of Beenakker et al., Montagna et al. and Cacciari et al., we conclude
that the total precision of our BHWIDE results is 0.3% (0.5%) in the LEP1/SLC
regime within +-100 MeV (+2.75/-2.5 GeV) of the Z peak. For LEP2, the
corresponding precision is currently estimated at 1.5%; the latter could be
improved if the data in LEP2 so require. Both precision tags represent clear
improvements over what is currently available in the literature.


title: NRQCD matrix elements in polarization of J-Psi produced from b-decay

abstract:
  We present the non-relativistic QCD (NRQCD) prediction for the polarization
of the J-Psi produced in b to J-Psi + X, as well as the helicity-summed
production rate. We propose that these observables provide a means of measuring
the three most important color-octet NRQCD matrix elements involved in J-Psi
production. Anticipating the measurement of the polarization parameter alpha,
we determine its expected range given current experimental bounds on the
color-octet matrix elements.


title: Heavy Quarks Photoproduction

abstract:
  The state of the art of the theoretical calculations for heavy quarks
photoproduction is reviewed. The full next-to-leading order calculation and two
possible resummations, the high energy one for total cross sections and the
large $p_T$ one for differential cross sections, are described.


title: $R$-parity-Violating Supersymmetric Yukawa Couplings: A Mini-review

abstract:
  I review the bounds on the $R$-parity-violating supersymmetric Yukawa
couplings from the considerations of proton stability, $n$--$\bar{n}$
oscillation, $\nu_e$-Majorana mass, neutrino-less double $\beta$ decay,
charged-current universality, $e$--$\mu$--$\tau$ universality, $\nu_\mu$--$e$
scattering, atomic parity violation, $\nu_\mu$ deep-inelastic scattering,
$K^{+}$-decays, $\tau$-decays, $D$-decays and from the precision LEP
electroweak observables. I also mention about the sparticle bounds at colliders
when the assumption of $R$-parity-conservation is relaxed. Finally, I mention
how $R$-parity-violating models have been invoked in an attempt to explain the
reported excess in ALEPH 4-jet events.


title:
Unravelling the $WW\gamma$ and $WWZ$ Vertices at the Linear Collider:
  $\bar{\nu} \nu\gamma$ and $\bar{\nu}\nu\bar{q}q$ final states

abstract:
  We perform a detailed analysis of the processes $e^+e^- \rightarrow \bar{\nu}
\nu\gamma$ and $\bar{\nu}\nu\bar{q}q$ at future linear $e^+e^-$ colliders and
assess their sensitivity to anomalous gauge boson couplings. We consider center
of mass energies $\sqrt{s}=$ 350, 500 and 800 GeV. We demonstrate that
significant improvements can be obtained if the phase space information for the
cross sections is used maximally. At 800 GeV the parameters
$\Delta\kappa_{\gamma}$ and $\lambda_{\gamma}$ can be constrained, at 95\% CL,
to about 0.02 and 0.01, while the parameters $\Delta\kappa_Z$, $\lambda_Z$ and
$\Delta g_1^Z$ can be probed down to about 0.009, 0.002 and 0.004 respectively.
The precision of these measurements is likely to be limited by statistical
errors at anticipated luminosities at these energies.


title: Comparative Study of the Hadronic Production of $B_c$ Mesons

abstract:
  The full order $\alpha_s^4$ perturbative QCD calculation of the production of
$B_c$ mesons at the Tevatron is compared with the fragmentation approximation.
The non-fragmentation diagrams, in which two or more quarks and/or gluons can
simultaneously be nearly on-shell, are important unless $P_T\gg M_{B_c}$.


title: Top Physics Review and Outlook

abstract:
  I review the status of the top quark, and look forward to three topics
relevant to future top-quark physics; spin correlation, single-top-quark
production, and unification.


title:
Collision Induced Decays of Electroweak Solitons: Fermion Number
  Violation with Two Initial Particles

abstract:
  This paper presents work done in collaboration with E. Farhi, J. Goldstone,
and A. Lue which is described in full in Ref. [1].
  We consider a variant of the standard electroweak theory in which the Higgs
sector has been modified so that there is a classically stable weak scale
soliton. We explore fermion number violating processes which involve soliton
decay. A soliton can decay by tunnelling under the sphaleron barrier or the
decay can be collision induced if the energy is sufficient for the barrier to
be traversed. We discuss classical solutions to the Minkowski space equations
of motion in which a soliton is kicked over the barrier by an incoming pulse.
We then consider a limit in which we can reliably estimate the amplitude for
soliton decay induced by collision with a single W-boson. This amplitude
depends on g like exp[-cg^(-1/3)], and is larger than that for spontaneous
decay via tunnelling in the same limit. Finally we show that in soliton decays,
light SU(2)_L doublet fermions are anomalously produced. Thus we have a
calculation of a two body process with energy above the sphaleron barrier in
which fermion number is violated.


title:
Cosmological and phenomenological implications of Wilsonian matter in
  realistic superstring derived models

abstract:
  Superstring phenomenology aims at achieving two goals. The first is to
reproduce the observed physics of the Standard Model. The second is to identify
experimental signatures of superstring unification which, if observed, will
provide further evidence for the validity of superstring theory. I discuss such
potential signatures of superstring unification. I propose that proton lifetime
constraints imply that the Standard Model gauge group must be obtained directly
at the string level. In this case the unifying gauge group, for example
$SO(10)$, is broken to the Standard Model gauge group by ``Wilson lines''. The
symmetry breaking by ``Wilson line'' has important implications. It gives rise
to exotic massless states which cannot fit into multiplets of the original
unifying gauge group. This is an important feature because it results in
conservation laws which forbid the interaction of the exotic ``Wilsonian''
states with the Standard Model states. The ``Wilsonian'' matter states then
have important phenomenological implications. I discuss two such implications:
exotic ``Wilsonian'' states as dark matter candidates and ``Wilsonian'' matter
as the messenger sector in gauge mediated dynamical SUSY breaking scenarios.


title: Combined Squark and Gluino Mass Bounds from LEP Data

abstract:
  Under the assumption of gaugino mass unification at a high scale, chargino
and neutralino masses depend on the value of the gluino mass, which itself
becomes a function of squark masses through self-energy corrections. We
demonstrate that this leads to combined bounds on squark and gluino masses from
the limits on chargino, neutralino and Higgs boson masses obtained in the CERN
LEP-1 and LEP-1.5 runs. These bounds turn out to be comparable to those
obtained from direct searches at the Fermilab Tevatron and may be expected to
improve as LEP energies go higher.


title: The effect of Silk damping on primordial magnetic fields

abstract:
  We study the effects of plasma viscosity on the dynamics of primordial
magnetic fields by simulating magnetohydrodynamics in the early universe by
appropriate non-linear cascade models. We find numerically that even in the
presence of large kinetic viscosity, magnetic energy is transferred to large
length scales. There are indications, however, that the inverse cascade stops
at a given time which depends on the magnitude of viscosity. For realistic
viscosities we do not find equipartition between magnetic and kinetic energies.


title: Test of the Equivalence Principle from K Physics

abstract:
  A violation of the equivalence principle (VEP) in the Kaon system can, in
principle, induce oscillations between $K^\circ$ and $\overline{K^\circ}$ in a
manner that need not violate CPT conservation. We show that such a
CPT-conserved VEP mechanism could be clearly tested experimentally through the
energy dependence of the $K_L-K_S$ mass difference and discuss constraints
imposed by present experiments.


title: Chemical Equilibration of an Expanding Quark-Gluon Plasma

abstract:
  The chemical equilibration of the parton distribution in collisions of two
heavy nuclei at the CERN Large Hadron Collider is investigated. Initial
conditions are obtained from a self-screened parton cascade calculation. The
onset of transverse expansion of the system is found to impede the chemical
equilibration. The system initially approaches chemical equilibrium, but then
is driven away from it, when the transverse velocity becomes large.


title: Analysis of Low-$x$ Gluon Density from the $F_2$ Scaling Violations

abstract:
  We present an analysis of the current methods of approximate determination of
the gluon density $G(x,Q^2)$ at low-$x$ from the scaling violations of the
proton structure function $F_2(x,Q^2)$. The gluon density is obtained from
DGLAP equation by expansion at distinct points of expansion. We show that the
different results given by the proposed methods can be obtained from one new
expression considering the adequate points of expansion. It is shown in which
case the approximate determination of $G(x,Q^2)$ is reasonable.


title: Forward Jets at HERA and at the Tevatron

abstract:
  In this talk I consider forward-jet production at HERA and at the Tevatron as
a probe of the multiple gluon radiation induced by the BFKL evolution.


title: Large Rapidity Gaps between Jets at HERA and at the Tevatron

abstract:
  In this talk I consider the formation of a rapidity gap in hadron production
between two jets.


title: Confinement and Light-Front QCD

abstract:
  Numerical results for the (rest-frame) $Q\bar{Q}$ potential in light-front
quantized $QCD_{2+1}$ on a $\perp$ lattice are presented. Both in the
longitudinal as well as the $\perp$ spatial directions one obtains linear
confinement. The confinement mechanism in light-front QCD depends on the
orientation of the external charges: for longitudinally (with respect to the
boost direction in the infinite momentum frame) separated quarks, confinement
arises from the instantaneous interaction piece in the Hamiltonian while for
$\perp$ separated quarks, the confinement mechanism is similar to the one in
Hamiltonian lattice QCD. Nevertheless, already a very simple ansatz for the
effective link-field potential yields an almost rotationally symmetric
$Q\bar{Q}$ potential. The momentum carried by the glue strongly depends on the
orientation ("polarization") of the $Q\bar{Q}$ pair.


title: Enhanced photon production near the light-cone by a hot plasma

abstract:
  Strong collinear divergences, although regularized by a thermal mass, result
in a breakdown of the standard hard thermal loop expansion in the calculation
of the production rate of photons by a plasma of quarks and gluons using
thermal field theory techniques.


title: New Physics in CP Asymmetries and Rare B Decays

abstract:
  We review and update the effects of physics beyond the standard model on CP
asymmetries in B decays. These asymmetries can be significantly altered if
there are important new-physics contributions to \bqbqbar mixing. This same new
physics will therefore also contribute to rare, flavor-changing B decays.
Through a study of such decays, we show that it is possible to partially
distinguish the different models of new physics.


title: Production of Charm with a Photon at $p\bar{p}$ Colliders

abstract:
  The two particle inclusive cross section for the reaction
$p\bar{p}\rightarrow \gamma+c+X$ is studied in perturbative quantum
chromodynamics at order $O(\alpha_s^2)$. Differential distributions are
provided for various observables, and a comparison is made with preliminary
data from the CDF collaboration.


title: CPT, Strings, and Neutral-Meson Oscillations

abstract:
  A mechanism for spontaneous CPT breaking appears in string theory. Possible
implications for present-energy particle models are discussed. A realistic
string theory might exhibit CPT violation at levels detectable in current or
future experiments. Bounds on CPT from neutral-meson oscillations are
considered.


title:
Colour-octet Contributions to $x_F$ Distributions in $J/\psi$
  Hadro-production at Fixed Target Energies

abstract:
  We study J/\psi production at fixed-target energies, including the
colour-octet production mechanisms predicted by NRQCD. In an earlier paper, we
found that the octet components were crucial in understanding p_T-integrated
forward (x_F > 0) cross-sections. Here we make a detailed comparison of the
theoretical predictions with measured x_F distributions from fixed-target
experiments. We find that the model predictions agree well with data. Taking
into account higher orders in NRQCD, we argue that
sigma(chi_1)/sigma(chi_2)=0.6, in excellent agreement with data. Similiar
arguments also predict that sigma(chi)/sigma(J/psi) is roughly equal in photo-
and hadro-production.


title: Transverse Spin Distribution Function of Nucleon in Chiral Theory

abstract:
  At large N_c the nucleon can be viewed as a soliton of the effective chiral
lagrangian. This picture of nucleons allows a consistent nonperturbative
calculation of the leading-twist parton distributions at a low normalization
point. We derive general formulae for the transverse spin quark distribution
h_1(x) in the chiral quark-soliton model. We present numerical estimates and
compare them to the results obtained in other models.


title: Decay of $B_c^{*+}(3S) \to B^+D^0$

abstract:
  The decay constant for the vector state of $3S$-level in the heavy $(\bar b
c)$-quarkonium is evaluated in the framework of sum rules for the mesonic
currents. A scaling relation for the constants of vector quarkonia with
different quark contents is derived. The numerical estime gives
$\Gamma(B_c^{*+}(3S)\to B^+D^0)=90 \pm 35$ MeV.


title:
Threshold Top Quark Production in $e^+e^-$ Annihilation: Rescattering
  Corrections

abstract:
  Top quark pair production close to threshold at a next linear collider is
discussed, with special focus on the influence of rescattering corrections.
Numerical results are shown for the differential cross-section, i.e. the
momentum distribution and the forward backward asymmetry, and for moments of
the angular distribution of leptons arising from the semileptonic top quark
decay.


title:
pi-/pi+ ratio in heavy ions collisions: Coulomb effect or chemical
  equilibration?

abstract:
  We calculate the pi-/pi+ ratio for Pb+Pb at CERN/SPS energies and for Au+Au
at BNL/AGS energies using a (3+1) dimensional hydrodynamical model. Without
consideration of Coulomb effect an enhancement of this ratio at low mt is found
compatible with that observed in these experiments. Our calculations are based
on previous (3+1) dimensional hydrodynamical simulations (HYLANDER), which
described many other aspects of experimental data. In this model the observed
enhancement is a consequence of baryon and strangeness conservation and of
chemical equilibration of the system and is caused by the decay of produced
hyperons, which leads to a difference in the total number of positive and
negative pions as well. Based on the same approach, we also present results for
the pi-/pi+ ratio for S+S (CERN/SPS) collisions, where we find a similar
effect. The absence of the enhancement of the pi-/pi+ ratio in the S+S data
presented by the NA44 Collaboration, if confirmed, could indicate that chemical
equilibration has not yet been estabilished in this reaction.


title: Photoproduction of jets and the virtual structure of the photon

abstract:
  We compute the ratio between the direct and the resolved photon components of
single jet and dijet production in $ep$ collisions for the kinematical range
covered by the most recent ZEUS data. We analyse the phenomenological
consequences of different models for the structure of virtual photons in these
observables and compare them with the available data. We also comment on the
correlation between the so called $x_{\gamma}^{obs}$ and the `true'
$x_{\gamma}$, that can be inferred from the data.


title: Tests at a Tau/Charm Factory with Longitudinally Polarized Beams

abstract:
  In a recent paper, eight semileptonic parameters were defined to specify the
most general Lorentz-invariant spin correlation functions for tau semileptonic
decays. The parameters were physically defined in terms of tau-decay
partial-width intensities for polarized final states. This paper studies how
these parameters can be simply measured at a tau/charm factory with
longitudinally polarized beams without using spin-correlation techniques.
Thereby the parameters can also be used to bound the effective-mass scales $
\Lambda $ for ``new physics" such as arising from lepton compositeness,
leptonic CP violation, leptonic T violation, tau weak magnetism, weak
electricity, and/or second-class currents.


title: Anomalous electromagnetic processes at high temperatures

abstract:
  Chiral theories of constituent quarks interacting with bosons and photons at
high temperatures are studied. In the expected chirally symmetric phase
effective electromagnetic anomalous couplings for e.g. $\pi \sigma \to \gamma
\gamma, ~ \gamma \to \pi \pi \pi \sigma, $ etc., are derived by applying
functional methods.


title:
Anomalous $U(1)$ Mediated SUSY Breaking, Fermion Masses and Natural
  Suppression of FCNC and CP Violating Effects

abstract:
  We construct realistic supergravity models where supersymmetry breaking
arises from the $D$-terms of an anomalous $U(1)$ gauge symmetry broken at the
Planck scale. The model has the attractive feature that the gaugino masses, the
$A$ and $B$ terms and the mass splittings between the like-charged squarks of
the first two generations compared to their average masses are all suppressed.
As a result, the electric dipole moment of the neutron as well as the flavor
changing neutral current effects are predicted to be naturally small. These
models predict naturally the expected value of the $\mu$-term and also have the
potential to qualitatively explain the observed mass hierarchy among quarks and
leptons.


title: Thermodynamics of QCD at high temperature

abstract:
  A hierarchy of effective field theories is used to separate the contributions
from different momentum scales and to calculate the free energy of QCD at high
temperature in powers of the coupling constant up to order $g^5$. The behavior
of the perturbative series will also be discussed.


title:
Diffractive Production of $b \bar b$ in Proton - Antiproton Collision at
  the Tevatron

abstract:
  We show that the cross section of the diffractive production of $b \bar b$
can be described as the sum of two contributions: the first is proportional to
the probability of finding a small size $b \bar b$ color dipole in the fast
hadron wave function before the interaction with a target, while the second is
the $b \bar b$-production after or during the interaction with the target. The
formulae are presented as well as the discussion of the interralation between
these two contributions and the Ingelman- Schlein and coherent diffraction
mechanisms. The main precdition is that the coherent diffraction mechanism
dominates at least at the Tevatron Energies, giving the unique possibility to
study it experimentally.


title: Light Gluino and Tevatron Data

abstract:
  A very light gluino ($m_{\tilde g} \lsim 2 \gev$) is still consistent with
experimental data and is attractive from a theoretical standpoint. This has
been shown to lead to a small gluino content of the proton. We use this effect
to demonstrate that such a light gluino could lead to a striking enhancement,
at Tevatron, of monojets accompanied by large missing momentum. A reanalysis of
the existing data may thus rule out a light gluino for a common squark mass of
upto $\sim 600 \gev$.


title: Baryonic Form Factors in the Nonrelativistic Quark Model

abstract:
  Weak current-induced baryonic form factors at zero recoil are evaluated in
the rest frame of the heavy parent baryon using the nonrelativistic quark
model. Contrary to previous similar work in the literature, our quark model
results do satisfy the constraints imposed by heavy quark symmetry for
heavy-heavy baryon transitions. Assuming a dipole $q^2$ behavior, we have
applied the quark model form factors to nonleptonic, semileptonic and weak
radiative decays of the heavy baryons.


title: Mesonic Form Factors in the Light-Front Quark Model

abstract:
  Form factors for $P\to P$ and $P\to V$ transitions due to the valence-quark
configuration are calculated directly in the physical time-like range of
momentum transfer within the light-front quark model. It is pointed out that
the Bauer-Stech-Wirbel type of light-front wave function fails to give a
correct normalization for the Isgur-Wise function at zero recoil in $P\to V$
transition. Some of the $P\to V$ form factors are found to depend on the
recoiling direction of the daughter mesons relative to their parents. Thus, the
inclusion of the non-valence contribution arising from quark-pair creation is
mandatory in order to ensure that the physical form factors are independent of
the recoiling direction.


title: Violation of universal Yukawa coupling and quark masses

abstract:
  We analyse the quark mass hierarchy and CKM matrix using the universal Yukawa
coupling model with small violations precisely. We estimate the ranges of the
values of 8 violation parameters (delta1u, delta2u, delta3u, delta1d, delta2d,
delta3d, phi2, phi3) in our quark mass matrices satisfying quark mass ratios
and CKM matrix, where phi2, phi3 are phases. Without these phases, the solution
  satisfying quark mass ratios and CKM matrix is not obtained. These parameters
obtained can explain the CP violation effects.


title: Ferromagnetic Domain Wall and Primeval Magnetic Field

abstract:
  We show that coherent magnetic field is generated spontaneously when a large
domain wall is created in the early universe. It is caused by two dimensional
massless fermions bounded to the domain wall soliton. We point out that the
magnetic field is a candidate of primordial magnetic field.


title: Towards a next-to-leading logarithmic result in $B \to X_s \gamma$

abstract:
  The calculation of the $O(\a_s)$ virtual corrections to the matrix element of
the inclusive decay $b \to s \gamma$ is reported. These contributions
drastically reduce the large renormalization scale dependence of the leading
logarithmic calculation. Combining these results with the preliminary result
for the Wilson coefficient $C_7(m_b)$ calculated recently by Chetyrkin, Misiak,
and M\"unz, we estimate the branching ratio to be $BR(B \to X_s \gamma)=(3.25
\pm 0.50) \times 10^{-4}$.


title: Spontaneous CP violation in the left-right model and the kaon system

abstract:
  A left-right model with spontaneous $CP$ breakdown, consistent with the
particle physics phenomenology, is presented. Constraints on free parameters of
the model: mass of the new right handed gauge boson $M_2$ and ratio $r$ of the
two vacuum expectation values of the bidoublet, are found from the measurement
of $\epsilon$ in the kaon system. For most of the parameter space, $M_2$ is
restricted to be below 10 TeV. Higher masses can be achieved only by fine
tuning of Kobayashi-Maskawa matrix elements, quark masses, $r$ and the phase
$\alpha$ which is the unique source of $CP$-violation in the model. Large
number of combinations of signs of quark masses, which are observables of the
model, are found to be not allowed since they contradict with data. The range
of $\epsilon'/\epsilon$ the model predicts is around $10^{-4}$ in magnitude.


title: A Unified picture of glueball candidates $f_0(1500)$ and $f_0(1700)$

abstract:
  A simple mixing scheme describing the $f_0(1500)$ and the $f_0(1700)$ as
mixed states of a $\bar s s$ meson and a digluonium is reconsidered at the
light of new experimental data.


title:
Higgs signals and hard photons at the Next Linear Collider: the
  $ZZ$-fusion channel in the Standard Model

abstract:
  In this paper, we extend the analyses carried out in a previous article for
$WW$-fusion to the case of Higgs production via $ZZ$-fusion within the Standard
Model at the Next Linear Collider, in presence of electromagnetic radiation due
real photon emission. Calculations are carried out at tree-level and rates of
the leading order (LO) processes $e^+e^-\rightarrow e^+e^- H \ar e^+e^- b\bar b
$ and $e^+e^-\rightarrow e^+e^- H \ar e^+e^- WW \ar e^+e^- \mathrm{jjjj}$ are
compared to those of the next-to-leading order (NLO) reactions
$e^+e^-\rightarrow e^+e^- H (\gamma)\ar e^+e^- b\bar b \gamma$ and
$e^+e^-\rightarrow e^+e^- H (\gamma)\ar e^+e^- WW (\gamma) \ar e^+e^-
\mathrm{jjjj}\gamma$, in the case of energetic and isolated photons.


title:
Improved Effective Vector-Boson Approximation for Hadron-Hadron
  Collisions

abstract:
  An improved effective vector-boson approximation is applied to hadron-hadron
collisions. I include an approximative treatment and compare with a complete
perturbative calculation for the specific example of $ZZ$ production. The
results are also compared with existing approaches. The effective vector-boson
approximation in this form is accurate enough to reproduce the complete
calculation within 10%. This is true even far away from a possible Higgs boson
resonance where the transverse intermediate vector-bosons give the dominant
contribution.


title: Theory of Double Hard Diffraction

abstract:
  In this review talk I consider the physics of rapidity gaps between two jets
at hadron colliders, as a preliminary investigation toward understanding the
production of a Higgs boson via weak boson fusion at the LHC.


title: Ghost poles and chiral symmetry in $\pi N$ scattering

abstract:
  We solve the Schwinger-Dyson equation for the nucleon propagator in the
vacuum using $\pi$, $\sigma$, and $\omega$ mesons. For bare interaction
vertices (Hartree-Fock approximation) we obtain a pair of complex-conjugated
poles (ghost poles) and for vertices dressed by phenomenological form-factors
these ghosts disappeared. We use these two different approaches to evaluate the
scattering lengths and the phase shifts for the $\pi N$ scattering at
threshold. Our results show that only when the form factors are present is
possible to obtain a good agreement with the low-energy observables.


title: Baryon Number Non-Conservation and the Topology of Gauge Fields

abstract:
  An introduction to the subject of baryon number non-conservation in the
electroweak theory at high temperatures or energies is followed by a summary of
our discovery of an infinite surface of sphaleron-like configurations which
play a key role in baryon-number non-conserving transitions in a hot
electroweak plasma.


title: NRQCD Prediction for the Polarization of the J/psi Produced from b-decay

abstract:
  Presented at the Meeting of the Division of Particles and Fields, August
1996, in Minneapolis. The work presented here is based upon a recent paper
(hep-ph/9608413) done in collaboration with Oscar F. Hernandez, Ivan Maksymyk,
and Helene Nadeau. The NRQCD predictions for the polarization of the J/psi
produced in b->J/psi+X, as well as the helicity-summed production rate are
presented.


title: The Universe after inflation: the wide resonance case

abstract:
  We study numerically the decay of massive and massless inflatons into massive
excitations, via a $\phi^2 X^2$ coupling, in the expanding Universe. We find
that a wide enough resonance can survive the Universe expansion, though account
for the expansion is very important for determining precisely how wide it
should be. For a massive inflaton, the effective production of particles with
mass ten times that of the inflaton requires very large values of the resonance
parameter $q$, $q\gsim 10^8$. For these large $q$, the maximal size of produced
fluctuations is significantly suppressed by the back reaction, but at least
within the Hartree approximation they are still not negligible. For the
massless inflaton with a $\lambda\phi^4/4$ potential, the Universe expansion
completely prevents a resonance production of particles with masses larger than
$\sqrt{\lambda}\phi(0)$ for $q$ up to $q=10^6$.


title:
Deep inelastic scattering on the deuteron in the Bethe-Salpeter
  formalism II: Realistic $NN$-interaction

abstract:
  We present a systematic study of the leading twist structure functions of the
deuteron, F_2^D, b_{1,2}^D and g_1^D in a fully relativistic approach. Our
study is based on a realistic Bethe-Salpeter amplitude for the deuteron, which
is obtained as a solution to the homogeneous Bethe-Salpeter equation with a
realistic NN kernel. Particular effort is made to connect the structure
functions to the densities of the appropriate charges and currents. This allows
for a systematic comparison between the relativistic and nonrelativistic
calculations, by analysing the same densities in both approaches. Thus, the
sources of the relativistic effects in the structure functions are understood
and clearly distinguished from variations caused by the differences in the
model parameters. We present both the formalism and extensive numerical
calculations for all steps of our analysis. We find that the nonrelativistic
and relativistic calculations are qualitatively very much alike. However, three
main features systematically distinguish a consistent relativistic approach
from the nonrelativistic one: (i) the binding effects are larger, (ii) the
effect of Fermi motion at high $x$ is stronger and (iii) the relativistic
description of the structure functions b_{1,2}^D is fully consistent, unlike
the nonrelativistic approach, which is internally inconsistent and violates the
fundamental sum rules.