title: Symmetry breaking via fermion 4-point functions

abstract:
  We construct the effective action and gap equations for nonperturbative
fermion 4-point functions. Our results apply to situations in which fermion
masses can be ignored, which is the case for theories of strong flavor
interactions involving standard quarks and leptons above the electroweak scale.
The structure of the gap equations is different from what a naive
generalization of the 2-point case would suggest, and we find for example that
gauge exchanges are insufficient to generate nonperturbative 4-point functions
when the number of colors is large.


title:
The Influence of Multiplicity Distribution on the Erraticity Behavior of
  Multiparticle Production

abstract:
  The origin of the erraticity behaviour observed recently in the experiment is
studied in some detail. The negative-binomial distribution is used to fit the
experimental multiplicity distribution. It is shown that, with the multiplicity
distribution taken into account, the experimentally observed erraticity
behaviour can be well reproduced using a flat probability distribution. The
dependence of erraticity behaviour on the width of multiplicity distribution is
studied.


title:
CP-odd Higgs boson production in association with Neutral gauge boson in
  High-Energy $e^+e^-$ Collisions

abstract:
  We study the associated production of a CP-odd Higgs boson $A^0$ with a
neutral gauge boson ($Z$ or photon) in high-energy $e^+ e^-$ collisions at the
one-loop level in the framework of Two Higgs Doublet Models (THDM). We find
that in the small $\tan\beta$ regime the top quark loop contribution is
enhanced leading to significant cross-sections (about a few fb), while in the
large $\tan\beta$ regime the cross-section does not attain observable rates.


title: Relations Between Polarized Structure Functions

abstract:
  The status of the twist-2 and the twist-3 integral relations between
polarized structure functions in deep inelastic scattering is discussed. The
relations can be tested in the upcoming experiments in the range $Q^2 \gsim
M_p^2$.


title: From QCD to heavy ion collisions

abstract:
  This talk will discuss how heavy ion experiments, when moving from SPS (10 +
10 GeV) to RHIC (100+100 GeV) and to LHC (2750+2750 GeV), will enter a new
domain of QCD in which the production of even large pT gluons is so abundant
that it is simultaneously perturbative but such that the phase space density of
gluons is saturated. The saturation scale is estimated, quantitative numbers
for the initial production of gluons at the LHC are given and options for their
subsequent evolution are outlined. For parametrically large nuclei and
energies, classical field methods will be applicable.


title: Chern-Simons Number Diffusion and Hard Thermal Loops on the Lattice

abstract:
  We develop a discrete lattice implementation of the hard thermal loop
effective action by the method of added auxiliary fields. We use the resulting
model to measure the sphaleron rate (topological susceptibility) of Yang-Mills
theory at weak coupling. Our results give parametric behavior in accord with
the arguments of Arnold, Son, and Yaffe, and are in quantitative agreement with
the results of Moore, Hu, and Muller.


title: Fracture functions in the very forward limit

abstract:
  This talk gives a brief discussion of extended fracture functions, which
parametrise the non-perturbative physics in the target fragmentation region of
semi-inclusive DIS. In the forward limit z -> 1, it can be seen that fracture
functions can be identified with insertions of composite operators. This
enables polarised fracture functions to be used to test a target-independence
hypothesis of the ``proton spin effect''.


title: Initial-Final-State Interference in the Z line-shape

abstract:
  The uncertainty in the determination of the Z line-shape parameters coming
from the precision of the calculation of the Initial-State Radiation and
Initial--Final-State Interference is 2 10**(-4) for the total cross section
sigma zero(had) at the Z peak, 0.15 MeV for the Z mass M Z, and 0.1 MeV for the
Z width Gamma Z. Corrections to Initial--Final-State Interference beyond
\Order{\alpha^1} are discussed.


title:
The $\nu_\mu \leftrightarrow \nu_s$ interpretation of the atmospheric
  neutrino data and cosmological constraints

abstract:
  The data on atmospheric neutrinos can be explained assuming the existence of
oscillations between muon neutrinos and light sterile neutrinos with mixing
close to maximal, and Delta_m^2 approximately equal to 3 E-3 (eV^2). This
interpretation of the data is in potential conflict with the successes of big
bang nucleosynthesis (BBN), since oscillations can result in a too large
contribution of the sterile state to the energy density of the universe at the
epoch of nucleosynthesis. The possibility to evade these cosmological
constraints has been recently the object of some controversy. In this work we
rediscuss this problem and find that the inclusion of a small mixing of the
sterile state with tau neutrino can result in the generation of a large lepton
asymmetry that strongly suppress the muon-sterile neutrino oscillations
eliminating the possible conflict with BBN bounds. In this scheme the mass of
the tau neutrino must be larger than few eV's and is compatible with
cosmological bounds. Our calculation is performed using a Pauli-Boltzmann
method. In this approach it is also possible to develop analytic calculations
that allow physical insight in the processes considered and give support to the
numerical results.


title: Physics at \ggam and \egam colliders

abstract:
  I discuss, what really new could give Photon Colliders ($\gamma\gamma$ and
$e\gamma$) after LHC and \epe Linear Collider operations.


title:
Dimensionless supersymmetry breaking couplings, flat directions, and the
  origin of intermediate mass scales

abstract:
  The effects of supersymmetry breaking are usually parameterized by soft
couplings of positive mass dimensions. However, realistic models also predict
the existence of suppressed, but non-vanishing, dimensionless
supersymmetry-breaking couplings. These couplings are technically hard, but do
not lead to disastrous quadratic divergences in scalar masses, and may be
crucial for understanding low-energy physics. In particular, analytic scalar
quartic couplings that break supersymmetry can lead to intermediate scale
vacuum expectation values along nearly-flat directions. I study the one-loop
effective potential for flat directions in the presence of dimensionless
supersymmetry-breaking terms, and discuss the corresponding renormalization
group equations. I discuss two applications: a minimal model of automatic
R-parity conservation, and an extension of this minimal model which provides a
solution to the \mu problem and an invisible axion.


title: Neutrino oscillations as a "which-path" experiment

abstract:
  The role of simple quantum mechanics in understanding neutrino oscillation
experiments is pointed out by comparison with two-slit and Bragg scattering
experiments. The importance of considering the beam and the detector as a
correlated quantum system is emphasized. Quantum mechanics alone shows that the
difference observed in the same neutrino detector at Super-Kamiokande between
upward and downward going neutrinos requires the existence of a neutrino mass
difference. The localization of the source and detector in space in the
laboratory system for long times leads to an uncertainty in the momentum but
not of the energy of the neutrino and to coherence between states having
different momenta and the same energy and not between states with different
energies.


title: Large Lepton Number and High Temperature Symmetry Breaking in MSSM

abstract:
  It is known that a large neutrino number, of the order of a few percent of
the entropy of the universe, leads to symmetry breaking at high temperature. We
show here that in the minimal supersymmetric standard model (MSSM) this implies
the breaking of electromagnetic charge invariance at T >> M_W allowing for the
solution of the monopole problem.


title: 3-3-1 exotic quark search at CERN LEPII-LHC

abstract:
  The 3-3-1 electroweak model is the simplest chiral extension of the standard
model which predicts single and double charged bileptons and exotic quarks
carrying -4/3 and 5/3 units of the positron charge. In this paper we study the
possibilities of the production and decay of one of these exotic quarks at CERN
LEPII-LHC collider. For typical vector bilepton, exotic quark masses and mixing
angles we obtained between 20 and 750 events per year. Angular distributions
are also presented.


title: The Skyrme Model for Baryons

abstract:
  We review the Skyrme model approach which treats baryons as solitons of an
effective meson theory. We start out with a historical introduction and a
concise discussion of the original two flavor Skyrme model and its
interpretation. Then we develop the theme, motivated by the large $N_C$
approximation of QCD, that the {\it effective} Lagrangian of QCD is in fact one
which contains just mesons of all spins. When this Lagrangian is (at least
approximately) determined from the meson sector it should then yield a zero
parameter description of the baryons. We next discuss the concept of chiral
symmetry and the technology involved in handling the three flavor extension of
the model at the collective level. This material is used to discuss properties
of the light baryons based on three flavor meson Lagrangians containing just
pseudoscalars and also pseudoscalars plus vectors. The improvements obtained by
including vectors are exemplified in the treatment of the {\it proton spin
puzzle}.


title: CP Violation and the Muon Anomaly in N=1 Supergravity

abstract:
  The one loop supersymmetric electro-weak correction to the anomalous magnetic
moment of the muon is derived in the minimal N=1 supergravity unification with
two CP violating phases. A numerical analysis of the CP violating effects on
$g_{\mu}-2$ is carried out with the cancellation mechanism to guarantee the
satisfaction of the experimental limits on the electric dipole moments of the
electron and on the neutron. It is found that the effects of the CP phases can
significantly affect the supersymmetric electro-weak correction to $g_{\mu}-2$,
and that the numerical size of such a correction can be as large or larger than
the Standard Model electro-weak correction to $g_{\mu}-2$. These results are of
import for the new Brookhaven experiment which is expected to increase the
sensitivity of the $g_{\mu}-2$ measurements by a factor of 20 and allow for a
test of the electro-weak correction in the near future.


title: Flavor and Spin Structure of Octet Baryons at Large x

abstract:
  The quark flavor and spin distributions in octet baryons are calculated both
in the SU(6) quark spectator diquark model and in a perturbative QCD (pQCD)
based model. It is shown that the $\Lambda$ has the most significant difference
in flavor structure at large $x$ between the two models, though the flavor and
spin structure of other baryons can also provide tests of different models. The
Drell-Yan process for $\Sigma^{\pm}$ beams on isoscalar targets can be used to
test different predictions concerning the valence quark flavor structure of the
$\Sigma^{\pm}$.


title: Bounds on Heavy-to-Heavy Baryonic Form Factors

abstract:
  Upper and lower bounds are established on the Lambda_b -> Lambda_c
semileptonic decay form factors by utilizing inclusive
heavy-quark-effective-theory sum rules. These bounds are calculated to leading
order in Lambda_QCD/m_Q and alpha_s. The O(alpha_s^2 beta_0) corrections to the
bounds at zero recoil are also presented. Several form factor models used in
the literature are compared with our bounds.


title: Left-Right Gauge Model in Nonassociative Geometry

abstract:
  We reformulate the left-right gauge model of Pati-Mohapatra in the framework
of nonassociative geometry. At the tree level we obtain the same mixing angles
as the ones predicted by SO(10) GUT. However the model does not show the parity
breakdown.


title: Leptogenesis in Inflationary Universe

abstract:
  We investigate the leptogenesis via decays of heavy Majorana neutrinos which
are produced non-thermally in inflaton decays. We make a comprehensive study on
the leptogenesis assuming various supersymmetric (SUSY) models for hybrid, new
and topological inflations. For an estimation of the lepton asymmetry we adopt
the Froggatt-Nielsen mechanism for mass matrices of quarks and leptons. We find
that all of these models are successful to produce the lepton asymmetry enough
to explain the baryon number in the present universe. Here we impose low
reheating temperatures such as $T_R \lesssim 10^8$ GeV in order to suppress the
abundance of gravitinos not to conflict with the big-bang nucleosynthesis.
Furthermore, we find that the leptogenesis works very well even with $T_R
\simeq 10^{6}$ GeV in the SUSY hybrid or new inflation model. It is known that
such a reheating temperature is low enough to suppress the abundance of
gravitinos of mass $m_{3/2} \simeq 100$ GeV--1 TeV. Thus, the leptogenesis is
fully consistent with the big-bang nucleosynthesis in a wide region of the
gravitino mass.


title:
The flavour asymmetry and quark-antiquark asymmetry in the
  $\Sigma^+$-sea

abstract:
  The sea quark content of the $\Sigma^+$ baryon is investigated using
light-cone baryon-meson fluctuation model suggested by Brodsky and Ma. It is
found that the $\Sigma^+$ sea is flavour asymmetric ($\dbar > \ubar > \sbar$)
and quark-antiquark asymmetric ($q \not= \qbar$). Our prediction for the
flavour asymmetry, $\dbar > \ubar > \sbar$, is significantly different from the
SU(3) prediction ($\dbar < \ubar < \sbar$), while our prediction for the
$d$-$\dbar$ asymmetry is consistent with the SU(3) prediction.


title:
Infra-red stable fixed points of Yukawa couplings in non-minimal
  supersymmetric standard model with R-parity violation

abstract:
  We study the renormalization group evolution and the infra-red stable fixed
points of the Yukawa couplings of the non-minimal supersymmetric standard model
(NMSSM) with R-parity violation. Retaining only the R-parity violating
couplings of higher generations, we analytically study the solutions of the
renormalization group equations of all the couplings of the model. We find that
there are no simultaneous non-trivial infra-red fixed points for all the
couplings of the model, and that the infra-red fixed point structure of the
model is similar to the MSSM with R-parity violation. In particular, we show
that only the baryon number violating coupling $\lambda^{''}_{233}$, together
with top- and bottom-quark Yukawa couplings, approaches a non-trivial infra-red
stable fixed point. However, this fixed point solution predicts a top-quark
Yukawa coupling which is incompatible with the top quark mass for any value of
$\tan\beta$.


title: Leptogenesis with Dirac Neutrinos

abstract:
  We describe a "neutrinogenesis" mechanism whereby, in the presence of
right-handed neutrinos with sufficiently small pure Dirac masses,
(B+L)-violating sphaleron processes create the baryon asymmetry of the
Universe, even when B=L=0 initially. It is shown that the resulting neutrino
mass constraints are easily fulfilled by the neutrino masses suggested by
current experiments. We present a simple toy model which uses this mechanism to
produce the observed baryon asymmetry of the Universe. (PostScript Errors
corrected in latest Version).


title:
Octet and Decuplet Baryons in a Confining and Covariant Diquark-Quark
  Model

abstract:
  We treat baryons as bound states of scalar or axialvector diquarks and a
constituent quark which interact through quark exchange. We obtain fully
four-dimensional wave functions for both octet and decuplet baryons as
solutions of the corresponding Bethe-Salpeter equation. Applications currently
under investigation are: electromagnetic and strong form factors and
strangeness production processes.


title: Bound States of the particles with Identical Charge in Magnetic Field

abstract:
  In this paper we consider bound states and resonances of the particles with
identical charge in the presence of the strong magnetic field.


title: Possible Spontaneous Breaking of Lorentz and CPT Symmetry

abstract:
  One possible ramification of unified theories of nature such as string theory
that may underlie the conventional standard model is the possible spontaneous
breakdown of Lorentz and CPT symmetry. In this talk, the formalism for
inclusion of such effects into a low-energy effective field theory is
presented. An extension of the standard model that includes Lorentz- and
CPT-breaking terms is developed. The restriction of the standard model
extension to the QED sector is then discussed.


title: Disoriented Chiral Condensates and Anomalous Production of Pions

abstract:
  The leading-particle effect and the factorization property of the scattering
amplitude in the impact parameter space are used to study semiclassical
production of pions in the central region. The mechanism is related to the
isospin-uniform solution of the nonlinear $ \sigma $-model coupled to quark
degrees of freedom. The multipion exchange potential between two quarks is
derived. It is shown thatthe soft chiral pion bremsstralung also leads to
anomalously large fluctuations in the ratio of neutral to charged pions. We
show that only direct production ofpions in the form of an isoscalar coherent
pulse without isovector pairs can lead to large neutral-charged fluctuations.


title: Angular Dependence of the Nuclear Enhancement of Drell-Yan Pairs

abstract:
  We calculate the nuclear enhancement in the angular distribution of Drell-Yan
pairs produced in proton-nucleus reactions. Nuclear effects are encoded in
universal twist-4 parton correlation functions. We find that the Lam-Tung
relation for the angular coefficients of the lepton-pair distribution holds for
the double-hard, but not for the soft-hard contribution. We also predict that
nuclear enhancement effects at RHIC energies can be large.


title: Hard exclusive and semi-exclusive meson production

abstract:
  I review recent theory developments for hard exclusive and semi-exclusive
production of mesons, emphasising the variety of physics issues that can be
studied in these processes.


title: Spin dependent structure function g_1 at low x and low Q^2

abstract:
  Theoretical description of the spin dependent structure function g_1(x,Q^2)
in the region of low values of x and Q^2 is presented. It contains the Vector
Meson Dominance contribution and the QCD improved parton model suitably
extended to the low Q^2 domain. Theoretical predictions are compared with the
recent experimental data in the low x, low Q^2 region.


title: Glueball production in hadron and nucleus collisions

abstract:
  We elaborate on the hypothesis that in high energy hadron hadron and nucleus
nucleus collisions the lowest mass glueballs are copiously produced from the
gluon rich environment especially at high energy density. We discuss the
particular glueball decay modes: $0^{++}, 2^{++} \to K \bar{K}$ and $0^{++} \to
\pi^{+} \pi^{-} \ell^{+} \ell^{-}$.


title: Searching for a W' at the Next-Linear-Collider using Single Photons

abstract:
  We examine the sensitivity of the process e+e- -> nu nubar + gamma to
additional W-like bosons which arise in various models. The process is found to
be sensitive to W' masses up to several TeV.


title: Fully supersymmetric CP violations in the kaon system

abstract:
  We show that, on the contrary to the usual claims, fully supersymmetric CP
violations in the kaon system are possible through the gluino mediated flavor
changing interactions. Both $\epsilon_K$ and ${\rm Re} (\epsilon' /
\epsilon_K)$ can be accommodated for relatively large $\tan\beta$ without any
fine tunings or contradictions to the FCNC and EDM constraints.


title:
Polarization of inclusively produced $\Lambda_c$ in a QCD based hybrid
  model

abstract:
  A hybrid model is presented for hadron polarization that is based on
perturbative QCD subprocesses and the recombination of polarized quarks to form
polarized hadrons. The model, originally applied to polarized $\Lambda$'s that
were inclusively produced by proton beams, is extended to include pion beams
and polarized $\Lambda_c$'s. The resulting polarizations are calculated as
functions of $x_F$ and $p_T$ for high energies and are found to be in fair
agreement with recent experiments.


title:
Bounds on anomalous gamma-gamma-H and Z-gamma-H couplings at future
  e-gamma linear colliders

abstract:
  We study the bounds on the anomalous contributions to the gamma-gamma-H and
Z-gamma-H vertices that can be obtained via the process e-gamma-->e H. We
consider the representative case of an intermediate Higgs mass production of
MH=120 GeV and for a center of mass energy of Sqrt{S}=500 GeV and Sqrt{S}=1500
GeV. We use a model independent analysis based on SU(2)xU(1) invariant
operators of dimension 6 added to the Standard Model lagrangian. We find that
this process provides an excelent way to put strong constraints both in the
sector of CP-even and CP-odd anomalous couplings contribution to the
gamma-gamma-H and Z-gamma-H vertices.


title:
More on Parametrization Relevant to Describe Violation of CP, T and CPT
  Symmetries in the $K^0-\bar{K^0}$ System

abstract:
  To study violation of CP, T and/or CPT symmetries in the $K^0-\bar{K^0}$
systems, one has to parametrize the relevant mixing parameters and decay
amplitudes in such a way that each parameter represents violation of these
symmetries in a well-defined way. Parametrization is of course not unique and
is always subject to phase ambiguities. We discuss these problems with freedom
associated with rephasing of final (or intermediate) as well as initial states
taken into account. We present a fully rephasing-invariant parametrization and
a particular rephasing-dependent parametrization, and give a couple of comments
related to these and other possible parametrizations.


title:
Tree-Penguin Interference and Tests for $\cos\gamma < 0$ in Rare $B\to
  PP$, $PV$ and $VV$ Decays

abstract:
  Recent rare $B \to PP$, $PV$ decay data suggest that factorization holds well
if, contrary to current fits, one has $\cos\gamma < 0$ where $\gamma \equiv
{\rm arg}(V_{ub}^*)$. We update previous results with light cone sum rule form
factors, which seem to work better. We then discuss various $B\to VV$ modes as
well as the $K^{*} \eta$ modes. Finding the pattern of $\rho^+\omega^0 <
\rho^+\rho^0$, $K^{*+}\rho^{-,0} > K^{*0}\rho^+$, $K^{*+}\omega^0 >
K^{*0}\omega^0$ and $K^{*+}\eta > K^{*0}\eta$ would strengthen the support for
$\cos\gamma < 0$. The electroweak penguin enhances (suppresses) the
$K^{*+}\rho^{0}$ ($K^{*0}\rho^{0}$) rate by a factor of 2, and finding
$K^{*+}\rho^{0} \simeq K^{*+}\rho^{-}$ would be strong evidence for the
electroweak penguin.


title:
More about on the short distance contribution to the "B_c -> B_u^*
  gamma" decay

abstract:
  We calculate the transition form factor for the 'B_c -> B_u^* gamma' decay
taking into account only the short distance contribution, in framework of QCD
sum rules method. We observe that the transition form factor predicted by the
QCD sum rules method is approximately two times larger compared to the result
predicted by the Isgur, Scora, Grinstein and Wise model.


title: Structure of the Quark Propagator at High Temperature

abstract:
  In the high temperature, chirally invariant phase of QCD, the quark
propagator is shown to have two sets of poles with different dispersion
relations. A reflection property in momentum space relates all derivatives at
zero-momentum of the particle and hole energies, the particle and hole damping
rates, and the particle and hole residues. No use is made of perturbation
theory.


title: Rho Parameter Constraints on Models with Large Compact Dimensions

abstract:
  In models with large extra dimensions, where quantum gravity effects become
strong at the TeV scale, the rho-parameter can receive large contributions from
one-loop diagrams involving exchange of multiple graviton and dilaton states.
These contributions are computed, taking into account cancellation of spurious
infrared divergences, and the (finite) results for d = 5 and 6 are compared
with current experimental data. It is shown that 5 large extra dimensions are
incompatible with the data and d = 6 is severely constrained.


title: Plasma wave instabilities induced by neutrinos

abstract:
  Quantum field theory is applied to study the interaction of an electron
plasma with an intense neutrino flux. A connection is established between the
field theory results and classical kinetic theory. The dispersion relation and
damping rate of the plasma longitudinal waves are derived in the presence of
neutrinos. It is shown that Supernova neutrinos are never collimated enough to
cause non-linear effects associated with a neutrino resonance. They only induce
neutrino Landau damping, linearly proportional to the neutrino flux and
$G_{\mathrm{F}}^{2}$.


title: Parity doublets and chiral symmetry restoration in baryon spectrum

abstract:
  It is argued that an appearance of the near parity doublets in the upper part
of the light baryon spectrum is an evidence for the chiral symmetry restoration
in the regime where a typical momentum of quarks is around the chiral symmetry
restoration scale. At high enough baryon excitation energy the nontrivial gap
solution, which signals the chiral symmetry breaking regime, disappears and the
chiral symmetry should be restored. Thus one observes a phase transition in the
upper part of the light baryon spectrum. The average kinetic energy of the
constituent quarks in this region is just around the critical one $3T_c$.


title: Mirror World versus large extra dimensions

abstract:
  Recently proposed low scale quantum gravity scenario is expected to have a
significant impact on the Mirror World hypothesis. Some aspects of this
influence is investigated here, assuming that the fundamental gravity scale is
near a TeV. It is shown that future colliders will be capable to produce the
mirror matter, but an experimental signature, which will distinguish such
events from the background, is unclear. The `smoking gun'' signals of the
Mirror World would be an observation of decays like $\Upsilon(2S)\to \tilde
\chi_{b2} \gamma $. But unfortunately the expected branching ratios are very
small. Finally, it is shown that a mirror supernova will be quite a spectacular
event for our world too, because a considerable amount of ordinary energy is
expected to be emitted in the first several seconds.


title: The World as a Dual Josephson Junction

abstract:
  We examine some of the implications of the field-theoretical mechanism for
the localization of gauge fields on hypersurfaces in higher-dimensional bulk
space-time. This mechanism exploits the analogy between confinement and dual
superconductivity. In the simplest case of a photon localized on a
(2+1)-dimensional surface in a (3+1)-dimensional bulk, we argue that the system
behaves like a dual Josephson junction. This implies that the effective gauge
theory on the surface is not free, but displays weak confinement with a linear
potential. We comment on the relevance of our results for the realistic case of
a (3+1)-dimensional surface in a space-time with one or more extra dimensions.


title:
Formation of Centauro and Strangelets in Nucleus-Nucleus Collisions at
  the LHC and their Identification by the ALICE Experiment

abstract:
  We present a phenomenological model which describes the formation of a
Centauro fireball in nucleus-nucleus interactions in the upper atmosphere and
at the LHC, and its decay to non-strange baryons and Strangelets. We describe
the CASTOR detector for the ALICE experiment at the LHC. CASTOR will probe, in
an event-by-event mode, the very forward, baryon-rich phase space 5.6 < \eta <
7.2 in 5.5 A TeV central Pb + Pb collisions. We present results of simulations
for the response of the CASTOR calorimeter, and in particular to the traversal
of Strangelets.


title: Classical Nambu-Goldstone fields

abstract:
  It is shown that a Nambu-Goldstone (NG) field may be coherently produced by a
large number of particles in spite of the fact that the NG bosons do not couple
to flavor conserving scalar densities like $\bar{\psi}\psi$. If a flavor
oscillation process takes place the phases of the pseudo-scalar or flavor
violating densities of different particles do not necessarily cancel each
other. The NG boson gets a macroscopic source whenever the total (spontaneously
broken) quantum number carried by the source particles suffers a net increase
or decrease in time. If the lepton numbers are spontaneously broken such
classical NG (majoron) fields may significantly change the neutrino oscillation
processes in stars pushing the observational capabilities of neutrino-majoron
couplings down to $m_{\nu}/300$ GeV.


title:
The effective potential of composite diquark fields and the spectrum of
  resonances in dense QCD

abstract:
  The effective potential of composite diquark fields responsible for color
symmetry breaking in cold very dense QCD, in which long-range interactions
dominate, is derived. The spectrum of excitations and the universality class of
this dynamics are described.


title:
Effects of friction on the chiral symmetry restoration in high energy
  heavy-ion collisions

abstract:
  We study the effects of friction on the chiral symmetry restoration which may
take place temporarily in high energy heavy ion collisions. The equations of
motion with friction are introduced to describe the time evolution of the
chiral condensates within the framework of the linear $\sigma$ model. Four
types of friction are used to study how the result is sensitive to the choice
of the friction. For the thermalization stage, the time dependent temperature
is parameterized so as to simulate the result of the parton-cascade model. It
is parameterized according to the one dimensional scaling hydrodynamics for the
subsequent cooling stage. The time development of the condensates and the
entropy production due to friction are calculated numerically. The time
interval in which the chiral symmetry is restored approximately is investigated
in detail for four types of friction. It is found that; (i) the maximum
temperature must be high enough (not lower than 230 MeV) and the friction must
be strong enough in order that the chiral symmetry restoration lasts for a long
time (not shorter than 3fm/c); (ii) the ratio of time interval in which chiral
symmetry is restored, to the time interval in which the temperature is higher
than the critical temperature is typically 0.5 when the friction is strong
enough; and (iii) the entropy due to the friction is mainly produced in the
early stage of the cooling. The effect of freezeout is discussed briefly.


title: On the $\eta'$ Gluonic Admixture

abstract:
  The $\eta'$ which is an $SU(3)_F$ singlet state can contain a pure gluon
component, gluonium. We examine this possibility by analysing all available
experimental data. It is pointed out that the $\eta'$ gluonic component may be
as large as 26%. We also show that the amplitude for $J/\psi -> \eta'\gamma$
decay obtains a notable contribution from gluonium.


title: A phenomenological study of BFKL evolution

abstract:
  The QCD dipole picture allows to build an unified theoretical description
-based on BFKL dynamics- of the total and diffractive nucleon structure
functions measured at HERA. We use a four parameter fit to describe the 1994 H1
proton structure function $F_{2}$ data in the low x, moderate $Q^{2}$ range.
The diffractive dissociation processes are discussed within the same framework,
and a 6 parameter fit of the 1994 H1 diffractive structure function data is
performed.
  The BFKL dynamics can also be successfully tested at the $e^+e^-$ collider
LEP and a future high energy linear collider. The total $\gamma^*\gamma^*$
cross-section is calculated in the Leading Order QCD dipole picture of BFKL
dynamics, and compared with the one from 2-gluon exchange. Next to Leading
order corrections to the BFKL evolution have been determined
phenomenologically, and are found to give very large corrections to the BFKL
cross-section, leading to a reduced sensitivity for observing BFKL effects. The
Y dependence of the cross-section remains a powerful tool to increase the ratio
between the BFKL and the 2-gluon cross-sections and is more sensitive to BFKL
effects, even in the presence of large higher order corrections.


title: Measurement of the diffractive structure function $F_2^{D(3)}$

abstract:
  Measurements of the diffractive structure function $F_2^{D(3)}(x_{\PO},
\beta, Q^2)$, describing the process $ep \to eXY$, are presented in the two
kinematic regions $0.4 \leq Q^2 \leq 5$, ${\rm GeV}^2$, $0.001 \leq \beta \leq
0.65$, and $200 \leq \beta \leq 800 {\rm GeV^2}$, $0.4 \leq \beta \leq 0.9$,
both with $\xpom < 0.05$, $M_{_Y} < 1.6 {\rm GeV}$ and $|t| < 1.0 {\rm GeV^2}$.
Together with published measurements at intermediate $Q^2$, the data are
compared with models based on QCD and Regge phenomenology. The diffractive
trajectory is found to have an intercept larger than that describing soft
hadronic data and consistent with that determined using previously published H1
measurements at intermediate $Q^2$ alone. The data are also parameterised using
a QCD motivated model based on the exchange of two gluons from the proton. In
this model, the higher twist contribution to $F_2^{D(3)}$ at large $\beta$ is
found to be important at low $Q^2$. The data are also compared with models
based on BFKL dynamics.


title:
Radiative $\eta'$ Decays, the Topological Susceptibility and the
  Witten-Veneziano Mass Formula

abstract:
  The formulae describing the radiative decays $\eta'(\eta)\rta\c\c$ in QCD
beyond the chiral limit are derived. The modifications of the conventional PCAC
formulae due to the gluonic contribution to the axial anomaly in the flavour
singlet channel are precisely described. The decay constants are found to
satisfy a modified Dashen formula which generalises the Witten--Veneziano
formula for the mass of the $\eta'$. Combining these results, it is shown how
the topological susceptibility in QCD with massive, dynamical quarks may be
extracted from measurements of $\eta'(\eta)\rta\c\c$.


title:
High-Energy Forward Scattering and the Pomeron: Simple Pole versus
  Unitarized Models

abstract:
  Using the largest data set available, we determine the best values that the
data at t=0 (total cross sections and real parts of the hadronic amplitudes)
give for the intercepts and couplings of the soft pomeron and of the rho/omega
and a/f trajectories. We show that these data cannot discriminate between a
simple-pole fit and asymptotic log square s and log s fits, and hence are not
sufficient to reveal the ultimate nature of the pomeron. However, we evaluate
the existing evidence (factorization, universality, quark counting) favouring
the simple-pole hypothesis. We also examine the range of validity in energy of
the fits, and show that one cannot rely on such fits in the region sqrt(s)<9
GeV. We also establish bounds on the odderon and the hard pomeron.


title:
Constraints on TeV-scale hybrid inflation and comments on non-hybrid
  alternatives

abstract:
  During hybrid inflation, the slowly-rolling inflaton field has a significant
coupling to the trigger field which is responsible for most of the potential.
Barring a fine-tuned accidental cancellation, this coupling induces a minimal
one-loop contribution to the inflaton potential. The requirement that this
contribution be not too large constrains a wide class of hybrid inflation
models. Assuming that the inflaton perturbation generates structure in the
Universe, the inflaton field and/or the trigger field after inflation have to
be bigger than $10^9\GeV$. This and other results make hybrid inflation at or
below the TeV scale problematical. (There is no problem with hybrid inflation
at the high energy scales normally considered.) `New' and thermal inflation
seem to be viable alternatives for inflation at or below the TeV scale,
including the case that quantum gravity is at the TeV scale. In any case,
supersymmetry is needed required during inflation, in order to protect a scalar
mass.


title: Models for Photon-photon Total Cross-sections

abstract:
  We present here a brief overview of recent models describing the
photon-photon cross-section into hadrons. We shall show in detail results from
the eikonal minijet model, with and without soft gluon summation.


title:
The odderon and spin-flip dependence of high energy proton-proton
  scattering

abstract:
  The sensitivity of the spin dependence of high energy pp scattering,
particularly the asymmetry A_{NN}, to the odderon is demonstrated. Several
possible ways of determining the spin dependence of the odderon coupling from
small-t data are presented.


title:
Predicting Proton-Air Cross Sections at sqrt s ~30 TeV, using
  Accelerator and Cosmic Ray Data

abstract:
  We use the high energy predictions of a QCD-inspired parameterization of all
accelerator data on forward proton-proton and antiproton-proton scattering
amplitudes, along with Glauber theory, to predict proton-air cross sections at
energies near \sqrt s \approx 30 TeV. The parameterization of the proton-proton
cross section incorporates analyticity and unitarity, and demands that the
asymptotic proton is a black disk of soft partons. By comparing with the p-air
cosmic ray measurements, our analysis results in a constraint on the inclusive
particle production cross section.


title: The Minimal Supersymmetric Leptogenesis

abstract:
  We reanalyze the supersymmetric leptogenesis model by one of the authors (HM)
and Yanagida based on \tilde{L} = H_u flat direction in detail. We point out
that the appropriate amount of baryon asymmetry can be generated in this model
with the neutrino mass matrix consistent with the atmospheric neutrino
oscillation and solutions to the solar neutrino problem, preferably the small
angle MSW solution. The reheating temperature can be low enough to avoid the
cosmological gravitino problem. This model is the minimal one because it does
not rely on any new physics beyond supersymmetry and Majorana neutrino masses.


title: Quantum Kinetic Equations and Dark Matter Abundances Reconsidered

abstract:
  Starting from a Caldeira-Leggett model for the interaction of a system with
an environment, Joichi, Matsumoto, and Yoshimura have reconsidered the
derivation of the quantum Boltzmann equation. They find an extra term that
accounts for the effects of virtual particles, and which drastically changes
the results for relic densities of stable, weakly interacting massive particles
(WIMPs), and for the decay products of unstable particles. We show, however,
that this modified Boltzmann equation does not properly account for the
interaction energy between the massive particles (which are decaying or
annihilating) and the thermal bath of light particles. We argue that the
conventional Boltzmann equation gives the correct result.

categories: hep-ph astro-ph cond-mat.stat-mech hep-th


title: Normalization Constants of Large Order Behavior

abstract:
  A perturbation scheme is discussed for the computation of the normalization
constant of the large order behavior arising from an ultraviolet renormalon. In
this scheme the normalization constant is expressed in a convergent series that
can be calculated using the ordinary perturbative expansion and the nature of
the renormalon singularity.


title: Hamiltonian approach to the bound state problem in QCD_2

abstract:
  Bosonization of the two-dimensional QCD in the large N_C limit is performed
in the framework of Hamiltonian approach in the Coulomb gauge. The generalized
Bogoliubov transformation is applied to diagonalize the Hamiltonian in the
bosonic sector of the theory, and the composite operators creating/annihilating
bosons are obtained in terms of dressed quark operators. The bound state
equation is reconstructed as a result of the generalized Bogoliubov
transformation, and the form of its massless solution, chiral pion, is found
explicitly. Chiral properties of the theory are discussed.


title: Effective Theory for Color-Flavor Locking in high Density QCD

abstract:
  We describe the low energy excitations of the diquark condensates in the
color-flavor locked phase of QCD with three massless flavors, at high baryon
densities, in terms of a non-linear effective lagrangian. Such a lagrangian is
formally seen to correspond to the lagrangian for the hidden gauge symmetry
description of the effective low energy chiral lagrangian, the role of the
hidden symmetry being played by color. In particular, this agrees with the
conjecture that the light degrees of freedom of the two phases are in
correspondence to each other (complementarity). The discussion includes
consideration of the breaking of Lorentz invariance in presence of matter
density.


title: Bosonic Preheating in Left-Right-Symmetric SUSY GUTs

abstract:
  We investigate the possibility of a bosonic preheating in the simplest model
of supersymmetric Hybridinflation (F-term inflation), which was considered
first by Dvali et al. Here the inflationary superpotential is of the
O'Raifertaigh-Witten type. The end of inflation is related to a non-thermal
phase transition, which in the context of left-right symmetric models lowers
the rank of the gauge group. Using the homogeneous classical field ansatz for
the appearing condensates, our results indicate that the parametric creation of
bosonic particles does not occure in the model under consideration.


title:
A Systematic Analysis of the Lepton Polarization Asymmetries in the Rare
  B Decay, B -> X_s\tau^+\tau^-

abstract:
  The most general model-independent analysis of the lepton polarization
asymmetries in the rare B decay, $\Bstt$, is presented. We present the
longitudinal, normal and transverse polarization asymmetries for the $\tau^+ $
and $\tau^-$, and combinations of them, as functions of the Wilson coefficients
of twelve independent four-Fermi interactions, ten of them local and two
nonlocal. These procedures will tell us which type of operators contributes to
the process. And it will be very useful to pin down new physics systematically,
once we have the experimental data with high statistics and a deviation from
the Standard Model is found.


title: Nuclear Deep-Inelastic Lepton Scattering and Coherence Phenomena

abstract:
  This review outlines our present experimental knowledge and theoretical
understanding of deep-inelastic scattering on nuclear targets. The emphasis is
primarily on nuclear coherence phenomena, such as shadowing, where the key
physics issue is the exploration of hadronic and quark-gluon fluctuations of a
high-energy virtual photon and their passage through the nuclear medium. New
developments in polarized deep-inelastic scattering on nuclei are also
discussed, and more conventional binding and Fermi motion effects are
summarized. The report closes with a brief outlook on vector meson
electroproduction, nuclear shadowing at very large Q^2 and the physics of high
parton densities in QCD.


title:
R-parity violation and top quark polarization at the Fermilab Tevatron
  collider

abstract:
  The lepton or baryon number violating top quark interactions in the
supersymmetric standard model with R parity violation contribute to the process
d dbar to t tbar at the tree level via the t- or u-channel sfermion exchange.
Since these interactions are chiral, they induce polarization to the top quark
in the t tbar events at hadron colliders. We show in this article that the
polarization can be a useful observable for probing these interactions at the
upgraded Fermilab Tevatron collider, because the polarization is expected to be
very small in the standard model.


title: epsilon'/epsilon in the 1/N_c Expansion

abstract:
  We present a new analysis of the ratio epsilon'/epsilon which measures the
direct CP violation in K\to\pi\pi decays. We use the 1/N_c expansion within the
framework of the effective chiral lagrangian for pseudoscalar mesons. From
general counting arguments we show that the matrix element of the operator Q_6
is not protected from possible large 1/N_c corrections beyond its large-N_c or
VSA value. Calculating the 1/N_c corrections, we explicitly find that they are
large and positive. Our result indicates that a \Delta I=1/2 enhancement is
operative for Q_6 similar to the one of Q_1 and Q_2 which dominate the CP
conserving amplitude. This enhances epsilon'/epsilon and can bring the standard
model prediction close to the measured value for central values of the
parameters.


title: Hyperon Radii

abstract:
  A survey of the experimental data on the charge and strong hadronic radii is
given. A new, however preliminary value of the \Sigma^- charge radius allows to
include also hyperons in the systematics. The presented data on the hadronic
radii give the first hint of their dependence on the strangeness content. An
estimate of the constituent quark size is given.


title: QCD Constraints on Form Factor Shapes

abstract:
  This talk presents an introduction to the use of dispersion relations to
constrain the shapes of hadronic form factors consistent with QCD. The
applications described include methods for studying |V_{cb}| and |V_{ub}|, the
strange quark mass, and the pion charge radius.


title: Gapless Color Superconductivity

abstract:
  We present the dispersion relations for quasiparticle excitations about the
color-flavor locked ground state of QCD at high baryon density. In the presence
of condensates which pair light and strange quarks there need not be an energy
gap in the quasiparticle spectrum. This raises the possibility of gapless color
superconductivity, with a Meissner effect but no minimum excitation energy.
Analysis within a toy model suggests that gapless color superconductivity may
occur only as a metastable phase.


title: $e^+e^- \to t \bar t H$ with Non-standard Higgs Boson Couplings

abstract:
  We consider a general effective Lagrangian for couplings of a Higgs boson to
the top-quark to dimension-six operators including CP violation effects.
Constraints on some of them are derived from the $Z\to b\bar b$ data. We study
the process $e^+e^- \to t\bar t H$ to probe the non-standard couplings. We find
that at a linear collider with a c. m. energy $\sqrt s \sim 0.5-1.5$ TeV and a
high luminosity of 10-1000 fb$^{-1}$, these non-standard couplings may be
sensitively probed.


title: Resonant Two-body D Decays

abstract:
  The contribution of a $K^*(1430)$ $0^+$ resonance to $D^0\to K^-\pi^+$ is
calculated by applying the soft pion theorem to $D^+ \to K^* \pi^+$, and is
found to be about 30% of the measured amplitude and to be larger than the
$\Delta I=3/2$ component of this amplitude. We estimate a 70% contribution to
the total amplitude from a higher $K^*(1950)$ resonance. This implies large
deviations from factorization in D decay amplitudes, a lifetime difference
between D^0 and D^+, and an enhancement of $D^0-\bar D^0$ mixing due to SU(3)
breaking.


title: Fourth Generation b-prime decays into b + Higgs

abstract:
  If a fourth generation quark exists whose mass is below 255 GeV, then the
only two-body charged current decay, b'-->cW, is doubly-Cabibbo suppressed. For
this reason, CDF has searched for the one-loop neutral current decay b' --> bZ,
assuming that the branching ratio into bZ is 100%; an analysis giving the
bounds on m_b' for smaller branching ratios is in preparation. In this Report,
we examine the neutral current decay b' --> bH, which will occur if the Higgs
mass is less than m_b'-m_b. Four different cases are examined: the sequential
case, the non-chiral isosinglet case, the non-chiral isodoublet case, and a
two-Higgs model with flavor-changing neutral currents. In the first three of
these, the rates for b' --> bZ and b' --> bH are comparable, assuming
comparable phase space factors; in the fourth, b' --> bH is completely
dominant. Thus, we emphasize the importance of giving b' mass bounds as a
function of the branching ratio into bZ, since the assumption of a 100%
branching ratio for b' --> bZ may only be valid if the Higgs mass is near or
above the b' mass.


title: Expansion of True Vacuum Bubbles at the End of Inflation

abstract:
  The dynamics of false vacuum decay at the end of inflation is studied. It is
shown that the creation of a new phase is mainly stimulated by temperature
fluctuations. Moving walls of O(3)-symmetric bubbles weakly interact with their
surroundings at the inflation stage. Large field fluctuations might arise as a
result of wall collisions.


title: Cosmological Constants as Messenger between Branes

abstract:
  We present a supersymmetry-breaking scenario in which both the breaking in
the hidden sector with no-scale type supergravity and that in the observable
sector with gauge mediation are taken into account. The breaking scales in the
hidden and observable sectors are related through the vanishing condition of
the cosmological constant with a brane-world picture in mind. Suppressing
flavor-changing neutral currents, we can naturally obtain the gravitino,
Higgs(ino), and soft masses of the electroweak scale.


title: Nucleon Electromagnetic Form Factors in a chiral constituent-quark model

abstract:
  The electromagnetic form factors of the nucleon are calculated in an extended
chiral constituent-quark model where the effective interaction is described by
the exchange of pseudoscalar, vector, and scalar mesons. Two-body
current-density operators, constructed consistently with the extended model
Hamiltonian in order to preserve gauge invariance and current conservation, are
found to give a significant contribution to the nucleon magnetic form factors
and improve the estimates of the nucleon magnetic moments.


title: Skewed parton distributions and real and virtual Compton scattering

abstract:
  The soft physics approach to Compton scattering at moderately large momentum
transfer is reviewed. It will be argued that in that approach the Compton cross
section as well as other exclusive observables exhibit approximate scaling in a
limited range of momentum transfer. Invited talk held at the workshop on
exclusive and semi-exclusive processes at high momentum transfer, Jefferson
Lab, May (1999).


title:
J/Psi and Psi' total cross sections and formation times from data for
  charmonium suppression in $pA$ collisions

abstract:
  The recent data for E866 experiment on the x_F dependence for charmonium
suppression in pA collisions at 800 GeV are analyzed using a time- and
energy-dependent preformed charmonium absorption cross section
\sigma_{abs}^\psi(\tau,\sqrt{s}). For \sqrt{s}=10 GeV the initially (\tau=0)
produced premeson has an absorption cross section of \sigma_{pr}~3mb. At the
same energy but for \tau -> \infty one deduces for the total cross sections
\sigma_{tot}^{J/Psi N}=(2.8\pm 0.3)mb, \sigma_{tot}^{J/Psi N}= (10.5\pm 3.6)mb.
The date are compatible with a formation time \tau_{1/2}=0.6 fm/c.


title: Charmonium suppression by gluon bremsstrahlung in p-A and A-B collisions

abstract:
  Prompt gluons are an additional source for charmonium suppression in nuclear
collisions, in particular for nucleus-nucleus collisions. These gluons are
radiated as bremsstrahlung in N-N collisions and interact inelastically with
the charmonium states while the nuclei still overlap. The spectra and mean
number <n_g> of the prompt gluons are calculated perturbatively and the
gluon-Psi inelastic cross section is estimated. The integrated cross sections
for AB --> J/Psi (Psi')X for p-A and A-B collisions and the dependence on
transverse energy for S-U and Pb-Pb can be described quantitatively with some
adjustment of one parameter <n_g>\sigma(gPsi).


title:
Nonperturbative Effects in Gluon Radiation and Photoproduction of Quark
  Pairs

abstract:
  We introduce a nonperturbative interaction for light-cone fluctuations
containing quarks and gluons. The $\bar qq$ interaction squeezes the transverse
size of these fluctuations in the photon and one does not need to simulate this
effect via effective quark masses. The strength of this interaction is fixed by
data. Data on diffractive dissociation of hadrons and photons show that the
nonperturbative interaction of gluons is much stronger. We fix the parameters
for the nonperturbative quark-gluon interaction by data for diffractive
dissociation to large masses (triple-Pomeron regime). This allows us to predict
nuclear shadowing for gluons which turns out to be not as strong as
perturbative QCD predicts. We expect a delayed onset of gluon shadowing at $x
\leq 10^{-2}$ shadowing of quarks. Gluon shadowing turns out to be nearly scale
invariant up to virtualities $Q^2\sim 4 GeV^2$ due to presence of a semihard
scale characterizing the strong nonperturbative interaction of gluons. We use
the same concept to improve our description of gluon bremsstrahlung which is
related to the distribution function for a quark-gluon fluctuation and the
interaction cross section of a $\bar qqG$ fluctuation with a nucleon. We expect
the nonperturbative interaction to suppress dramatically the gluon radiation at
small transverse momenta compared to perturbative calculations.


title:
Supersymmetric CP Violation in $B \to X_s l^+ l^-$ in Minimal
  Supergravity Model

abstract:
  Direct CP asymmetries and the CP violating normal polarization of lepton in
inclusive decay B \to X_s l^+ l^- are investigated in minimal supergravity
model with CP violating phases. The contributions coming from exchanging
neutral Higgs bosons are included. It is shown that the direct CP violation in
branching ratio, A_{CP}^1, is of {\cal{O}}(10^{-3}) for l=e, \mu, \tau. The CP
violating normal polarization for l=\mu can reach 0.5 percent when tan\beta is
large (say, 36). For l=\tau and in the case of large \tan\beta, the direct CP
violation in backward-forward asymmetry, A_{CP}^2, can reach one percent, the
normal polarization of \tau can be as large as a few percent, and both are
sensitive to the two CP violating phases, \phi_\mu and \phi_{A_0}, and
consequently it could be possible to observe them (in particular, the normal
polarization of \tau) in the future B factories.


title: Pion-nucleon scattering inside the Mandelstam triangle

abstract:
  We study the third order pion-nucleon scattering amplitude obtained from
heavy baryon chiral perturbation theory inside the Mandelstam triangle. We
reconstruct the pion-nucleon amplitude in the unphysical region by use of
dispersion relations and determine the pertinent low-energy constants by a fit
to this amplitude. A detailed comparison with values obtained from phase shift
analysis is given. Our analysis leads to a pion-nucleon sigma-term of sigma(0)
= 40 MeV based on the Karlsruhe partial wave analysis. We have repeated the
same procedure using the latest solution of the VPI group and find a much
larger value for sigma(0).


title: On the Perturbative Nature of Color Superconductivity

abstract:
  Color superconductivity is a possible phase of high density QCD. We present a
systematic derivation of the transition temperature, T_C, from the QCD
Lagrangian through study of the di-quark proper vertex. With this approach, we
confirm the dependence of T_C on the coupling g, namely $T_C \sim \mu g^{-5}
e^{-\kappa/g}$, previously obtained from the one-gluon exchange approximation
in the superconducting phase. The diagrammatic approach we employ allows us to
examine the perturbative expansion of the vertex and the propagators. We find
an additional O(1) contribution to the prefactor of the exponential from the
one-loop quark self energy and that the other one-loop radiative contributions
and the two gluon exchange vertex contribution are subleading.


title:
Nothing anomalous about two-loop HBCPT: consistency with the LET for
  spin-dependent Compton scattering

abstract:
  The leading order contributions of processes involving anomalous pion-photon
vertices to forward spin-dependent Compton scattering from nucleons are
considered in heavy-baryon chiral perturbation theory. These all involve the
exchange of three pions between one or two photons and the nucleon, and hence
are two-loop processes. We find that the sum of these processes vanishes in the
manner predicted by the low energy theorem of Low, Gell-Mann and Goldberger as
the photon energy goes to zero. This provides the first consistency test of
two-loop HBCPT.


title: Mirror fermions and the hierarchy problem

abstract:
  The introduction of strongly-interacting mirror fermions with masses between
the weak scale and 1 TeV could offer a viable alternative to the Higgs
mechanism. The framework provided solves the hierarchy problem naturally and
predicts a rich phenomenology for present and future experiments.


title: Dynamical symmetry breaking with mirror fermions

abstract:
  Mirror fermions with masses around the weak scale could break dynamically the
electroweak symmetry if they were coupled with a new strong interaction. The
purpose of this talk is to show what sort of dynamics are needed in order to
render such theories phenomenologically viable.


title: The 7/11 rule: an estimate of m_rho/f_pi

abstract:
  We derive an estimate for the ratio of the rho mass and the pion decay
constant from an analysis of vector and axial-vector two-point functions using
large-Nc, lowest-meson dominance and the operator product expansion, in the
chiral limit. We discuss the extension of this analysis to the scalar and
pseudoscalar sector. Furthermore, this leads to a successful parameter-free
determination of the L_i couplings of the chiral Lagrangian if an improved
Nambu-Jona-Lasinio ansatz for Green functions is assumed at low energies.


title: A glueball-qqbar filter in central production

abstract:
  A study of central meson production as a function of the difference in
transverse momentum (dPT) of the exchanged particles shows that undisputed
qqbar mesons are suppressed at small dPT whereas the glueball candidates are
enhanced and that the production cross section for different resonances depends
strongly on the azimuthal angle between the two outgoing protons.


title: Bosonic Quartic Couplings at LEP2

abstract:
  We list the set of C and P conserving anomalous quartic vector bosons
self-couplings which can be tested at LEP2 through triple vector boson
production. We show how this set can be embedded in manifestly SU(2)xU(1) gauge
invariant operators exhibiting an SU(2)_c global symmetry. We derive bounds on
these various couplings and show the most relevant distributions that can
enhance their contribution. We also find that an e+e- collider running at 500
GeV can improve the LEP2 limits by as much as three orders of magnitude.


title: Epsilon' from supersymmetry with non universal A terms?

abstract:
  In supersymmetric theories with a motivated flavour structure, we investigate
the possibility that an epsilon' parameter as large as the measured value be
generated without conflicting with the bounds from electron and neutron
electric dipoles and mu --> e gamma.


title: The stealthy Higgs model at future Linear Colliders

abstract:
  We investigate the influence of scalar gauge singlets on Higgs signals at a
linear collider. These lead to a large invisible decay width of the Higgs. We
find that for high luminosities ($500-1000 fb^{-1}$) one can essentially cover
the allowed parameter range of the model.


title: Ultra high energy neutrinos from hidden-sector topological defects

abstract:
  We study Topological Defects (TD) in hidden (mirror) matter as possible
sources of ultra-high energy neutrinos. The hidden/mirror and ordinary matter
are assumed to interact very weakly through gravity or superheavy particles. An
inflationary scenario is outlined in which superheavy defects are formed in
hidden/mirror matter (and not in ordinary matter), and at the same time the
density of mirror matter produced at the end of inflation is much smaller than
that of ordinary matter. Superheavy particles produced by hidden-sector TD and
the products of their decays are all sterile in our world. Only mirror
neutrinos oscillate into ordinary neutrinos. We show that oscillations with
maximal mixing of neutrinos from both worlds are possible and that values of
$\Delta m^2$, needed for for solution of solar-neutrino and
atmospheric-neutrino problems, allow the oscillation of ultra-high energy
neutrinos on a timescale of the age of the Universe. A model of mass-degenerate
visible and mirror neutrinos with maximal mixing is constructed. Constraints on
UHE neutrino fluxes are obtained. The estimated fluxes can be 3 orders of
magnitude higher than those from ordinary matter. Detection of these fluxes is
briefly discussed.


title:
Neutrino Oscillations from Supersymmetry without R-parity - Its
  Implications on the Flavor Structure of the Theory

abstract:
  We discuss here some flavor structure aspects of the complete theory of
supersymmetry without R-parity addressed from the perspective of fitting
neutrino oscillation data based on the recent Super-Kamiokande result. The
single-VEV parametrization of supersymmetry without R-parity is first reviewed,
illustrating some important features not generally appreciated. For the flavor
structure discussions, a naive, flavor model independent, analysis is
presented, from which a few interesting things can be learned.


title:
Drell-Yan and J/psi Production in High Energy Proton-Nucleus and
  Nucleus-Nucleus Collisions

abstract:
  The distributions of outgoing protons and charged hadrons in high energy
proton-nucleus collisions are described rather well by a linear extrapolation
from proton-proton collisions. This linear extrapolation is applied to
precisely measured Drell-Yan cross sections for 800 GeV protons incident on a
variety of nuclear targets. The deviation from linear scaling in the atomic
number A can be accounted for by energy degradation of the proton as it passes
through the nucleus if account is taken of the time delay of particle
production due to quantum coherence. We infer an average proper coherence time
of 0.4 +/- 0.1 fm/c. Then we apply the linear extrapolation to measured J/psi
production cross sections for 200 and 450 GeV/c protons incident on a variety
of nuclear targets. Our analysis takes into account energy loss of the beam
proton, the time delay of particle production due to quantum coherence, and
absorption of the J/psi on nucleons. The best representation is obtained for a
coherence time of 0.5 fm/c, which is consistent with Drell-Yan production, and
an absorption cross section of 3.6 mb, which is consistent with the value
deduced from photoproduction of the J/psi on nuclear targets. Finally, we
compare to recent J/psi data from S+U and Pb+Pb collisions at the SPS. The
former are reproduced reasonably well with no new parameters, but not the
latter.


title: Structure and Production of Lambda Baryons

abstract:
  We discuss the quark parton structure of the $\Lambda$ baryon and the
fragmentation of quarks into $\Lambda$ baryons. We show that the hyperfine
interaction, responsible for the $\Delta$-$N$ and $\Sigma^0$-$\Lambda$ mass
splittings, leads not only to sizeable SU(3) and SU(6) symmetry breaking in the
quark distributions of the $\Lambda$, but also to significant polarized
non-strange quark distributions. The same arguments suggest flavor asymmetric
quark fragmentation functions and non-zero polarized non-strange quark
fragmentation functions. The calculated fragmentation functions give a good
description of all measured observables. We predict significant positive
$\Lambda$ polarization in semi-inclusive DIS experiments while models based on
SU(3) flavor symmetry predict zero or negative $\Lambda$ polarization. Our
approach also provides a natural explanation for the dependence of the maximum
of the $\xi=\ln(1/z)$ spectrum on the mass of the particles produced in
$e^+e^-$ annihilation.


title: Virtual photons in the pion form factors and the energy-momentum tensor

abstract:
  We evaluate the vector and scalar form factor of the pion in the presence of
virtual photons at next-to-leading order in two-flavor chiral perturbation
theory. We also consider the scalar and tensor pion form factors of the
energy-momentum tensor. We find that the intrinsic electromagnetic corrections
are of the expected size for the vector form factor and very small for the
charged pion scalar form factor. Detector resolution independent photon
corrections reduce the vector radius by about one percent. The scalar radius of
the neutral pion is reduced by two percent by isospin-breaking contributions.
We perform infrared regularization by considering electron-positron
annihilation into pions and the decay of a light Higgs boson into a pion pair.
We discuss the detector resolution dependent contributions to the various form
factors and pion radii.


title:
A Minimal See-Saw Model for Hierarchical Neutrino Masses with Large
  Mixing

abstract:
  The atmospheric and solar neutrino oscillation data suggest hierarchical
neutrino masses with at least one large mixing. The simplest see-saw models for
reconciling the two features are U(1) extensions of the SM with flavour
dependent gauge charges. I discuss a minimal model of this type containing two
heavy right-handed neutrinos, which have normal Dirac couplings to $\nu_\mu$
and $\nu_\tau$ but suppressed ones to $\nu_e$. It can naturally account for the
large (small) mixing solutions to the atmospheric (solar) neutrino oscillation
data.


title: The QCD-Oriented Vector Dominance Model

abstract:
  The total photoabsorption cross section on the nucleon is studied using
nondiagonal GVDM. Vector meson-nucleon scattering amplitudes are calculated in
two-gluon exchange approximation of QCD. The off-diagonal transitions of
diffraction dissociation type between different vector mesons and their
contributions to the expression for the total photoabsorption cross section on
the nucleon are also calculated. It is shown that destructive interference of
diagonal and off-diagonal terms is not effective. The main conclusion is that a
p-cut-off in gamma-quark antiquark transition is necessary for obtaining the
convergence in the summation over all vector meson contributions.


title: The Gluon Impact Factors

abstract:
  We calculate in the next-to-leading approximation the non-forward gluon
impact factors for arbitrary color state in the $t$-channel. In the case of the
octet state we check the so-called "second bootstrap condition" for the gluon
Reggeization in QCD, using the integral representation for the impact factors.
The condition is fulfilled in the general case of an arbitrary space-time
dimension and massive quark flavors for both helicity conserving and
non-conserving parts.


title: The Quark Impact Factors

abstract:
  We calculate in the next-to-leading approximation the non-forward quark
impact factors for both singlet and octet color representation in the
$t$-channel. The integral representation of the octet impact factor in the
general case of arbitrary space-time dimension and massive quark flavors is
used to check the so-called "second bootstrap condition" for the gluon
Reggeization at the next-to-leading logarithmic approximation in perturbative
QCD. We find that it is satisfied for both helicity conserving and
non-conserving parts. The integrations are then performed for the explicit
calculation of the impact factors in the massless quark case.


title: F-term Inflation in M-theory with Five-branes

abstract:
  We study F-term inflation in M-theory with and without five-brane moduli
fields. We show the slow rolling condition is not satisfied in M-theory without
five-brane moduli fields, but it can be satisfied in the case with
non-vanishing F-terms of five-brane moduli fields.


title: Bose-Einstein Effect in Z0 Decay and the Weight Method

abstract:
  We discuss the Bose-Einstein interference effect in multiparticle production.
After a short review of various methods of implementation of this effect into
Monte Carlo generators the weight method is presented in more detail and used
to analyze the data for hadronic Z0 decays. In particular, we consider the
possibility of deducing the two-particle weight factor from the experimental
data.


title: Estimating epsilon'/epsilon in the Standard Model

abstract:
  I discuss the comparison of the current theoretical calculations of
epsilon'/epsilon with the experimental data. Lacking reliable ``first
principle'' calculations, phenomenological approaches may help in understanding
correlations among different contributions and available experimental data. In
particular, in the chiral quark model approach the same dynamics which
underlies the Delta I = 1/2 selection rule in kaon decays appears to enhance
the K -> pi pi matrix element of the Q_6 gluonic penguin, thus driving
epsilon'/epsilon in the range of the recent experimental measurements.


title:
Is there a unique thermal source of dileptons in Pb(158 AGeV) + Au, Pb
  reactions?

abstract:
  An analysis of the dilepton measurements in the reactions Pb(158 A$\cdot$GeV)
+ Au, Pb points to a unique thermal source contributing to the invariant mass
and transverse momentum spectra. Effects of the flow pattern are discussed.


title:
Current-Target Correlations as a Probe of Delta_G/G in Polarized Deep
  Inelastic Scattering

abstract:
  The measurement of the polarized gluon distribution function Delta_G/G using
current-target correlations in the Breit frame of deep inelastic scattering is
proposed. The approach is illustrated using a Monte Carlo simulation of
polarized $ep$-collisions for HERA energies.


title: On the Construction of Quintessential Inflation Models

abstract:
  Attention has been recently drawn towards models in which inflation and
quintessence schemes are unified. In such `quintessential inflation' models, a
unique scalar field is required to play both the role of the inflaton and of
the late-time dynamical cosmological constant. We address the issue of the
initial conditions for quintessence in this context and find that, in the two
explicit examples provided, inflation can uniquely fix them to be in the
allowed range for a present day tracking.


title: "Secret" neutrino interactions

abstract:
  We review the information about a potentially strong non-standard
four-neutrino interaction that can be obtained from available experimental
data. By using LEP results and nucleosynthesis data we find that a contact
four-fermion neutrino interaction that involve only left-handed neutrinos or
both left-handed and right-handed neutrinos cannot be stronger than the
standard weak interactions. A much stronger interaction involving only
right-handed neutrinos is still allowed.


title: $\eta'\to\gamma\gamma$ and the topological susceptibility

abstract:
  The radiative decays $\eta'(\eta)\rta\gamma\gamma$ are discussed. The
modifications of the conventional PCAC formulae due to the gluonic contribution
to the flavour singlet axial anomaly are given. The decay constants satisfy a
modified Dashen formula which generalises the Witten--Veneziano formula for the
mass of the $\eta'$. It is shown how the topological susceptibility in QCD with
massive, dynamical quarks may be extracted from measurements of
$\eta'(\eta)\rta\gamma\gamma$.


title: Charmonium-Hadron Cross Section in a Nonperturbative QCD Approach

abstract:
  We calculate the nonperturbative $J/\Psi-N$ and $\Psi'-N$ cross sections with
the model of the stochastic vacuum which has been succesfully applied in many
high energy reactions. We also give a quantitative discussion of pre-resonance
formation and medium effects.


title: Does the Gluon Spin Contribute in A Gauge Invariant Way to Nucleon Spin?

abstract:
  Although the matrix element of the gluon spin operator in nucleon helicity
states is known to be independent of some special choices of gauge, we show
that it is not invariant under a general gauge transformation. We find that
there exists a simple means of obtaining the matrix element in a different
choice of gauge from a calculation made in one specific gauge. Similar
conclusions hold for other manifestly gauge-dependent operators present in the
QCD angular momentum operator.


title:
Unstable superheavy relic particles as a source of neutrinos responsible
  for the ultrahigh-energy cosmic rays

abstract:
  Decays of superheavy relic particles may produce extremely energetic
neutrinos. Their annihilations on the relic neutrinos can be the origin of the
cosmic rays with energies beyond the Greisen-Zatsepin-Kuzmin cutoff. The red
shift acts as a cosmological filter selecting the sources at some particular
value z_e, for which the present neutrino energy is close to the Z pole of the
annihilation cross section. We predict no directional correlation of the
ultrahigh-energy cosmic rays with the galactic halo. At the same time, there
can be some directional correlations in the data, reflecting the distribution
of matter at red shift z=z_e. Both of these features are manifest in the
existing data. Our scenario is consistent with the neutrino mass reported by
Super-Kamiokande and requires no lepton asymmetry or clustering of the
background neutrinos.


title: B-> K photon photon via intermediate eta'

abstract:
  We examine our previous conjecture that the eta' intermediate resonance has
the dominant role in the long distance contributions to B decay into two
photons and a strange final state hadron. We calculate the branching ratio of
the exclusive B-> K eta'-> K photon photon decay using the nonspectator
mechanism for eta' production in charmless hadronic B decays. It is shown that
the obtained branching ratio B^eta'(B-> K\gamma\gamma)~ 8.7 X 10^{-7} is more
than twice as large as the eta_c contribution to this decay mode.


title: Valence Parton Distribution Functions from Quantum ChromoDynamics

abstract:
  We show that two dimensional QCD can, to a good approximation, describe the
hadronic structure functions measured in Deep Inelastic Scattering. We
transform this theory into a new form, Quantum HadronDynamics (QHD), whose
semi-classical approximation is closer to nature. The Baryon is then a
topological soliton, and its structure function can be predicted by a
variational principle. This prediction can be tested by comparison with
measurements of neutrino scattering cross-sections.


title: The x-dependence of Parton Distributions Compared with Neutrino Data

abstract:
  We use the variational principle of Quantum HadronDynamics, an alternative
formulation of Quantum ChromoDynamics, to determine the wavefunction of valence
quarks in a baryon at a low value of Q^2. This can be used to predict the
structure function xF_3(x,Q^2) at higher values of Q^2 using the evolution
equations of perturbative QCD. This prediction is compared to the measurements
of neutrino scattering cross-section by the CDHS and CCFR experiments. The
agreement is quite good, confirming the validity of QHD as a way of studying
hadronic structure.


title: A New Analysis of Charge Symmetry Violation in Parton Distributions

abstract:
  To date, the strongest indication of charge symmetry violation in parton
distributions has been obtained by comparing the $F_2$ structure functions from
CCFR neutrino data and NMC muon data. We show that in order to make precise
tests of charge symmetry with the neutrino data, two conditions must be
satisfied. First, the nuclear shadowing calculations must be made explicitly
for neutrinos, not simply taken from muon data on nuclei. Second, the
contribution of strange and charm quarks should be calculated explicitly using
next-to-leading order [NLO] QCD, and the ``slow rescaling'' charm threshold
correction should not be applied to the neutrino data. When these criteria are
satisfied, the comparison is consistent with charge symmetry within the
experimental errors and the present uncertainty in the strange quark
distribution of the nucleon.


title: Transverse polarization distributions

abstract:
  I present a brief update on the transverse polarization distributions,
focusing on model calculations and phenomenological perspectives.


title: Birefringent Electroweak Textures

abstract:
  The behaviour of electromagnetic waves propagating through an electroweak
homilia string network is examined. This string network is topologically stable
as a cosmic texture, and is characterized by the spatial variation of the
isospin rotation of the Higgs field. As a consequence the photon field couples
to the intermediate vector bosons, producing a finite range electromagnetic
field. It is found that the propagation speed of the photon depends on its
polarization vector, whence an homilia string network acts as a birefringent
medium. We estimate the birefringent scale for this texture and show that it
depends on the frequency of the electromagnetic wave and the length scale of
the homilia string network.


title: Decay of pseudoscalars into lepton pairs and large-Nc QCD

abstract:
  The counterterm combination that describes the decay of pseudoscalar mesons
into charged lepton pairs at lowest order in chiral perturbation theory is
considered within the framework of QCD in the limit of a large number of
colours Nc. When further restricted to the lowest meson dominance approximation
to large-Nc QCD, our results agree well with the available experimental data.


title: No Massless Pions in Nambu-Jona-Lasinio Model due to Chiral Fluctuations

abstract:
  In contrast to common belief, the chirally symmetric Nambu--Jona-Lasinio
model does not contain massless pions, due to strong chiral fluctuations.
Although quarks acquire spontaneously a nonzero constituent mass $M$, pions
have a nonzero mass equal to the mass of $ \s $-mesons, both being of the order
of $M$. This result is found in several cutoff schemes. Our derivation is
nonperturbative, but involves a simple approximation (London limit) which
should, however, receive only quantitative, no qualitative corrections.


title: The Anti-quark Distribution Function of the Baryon

abstract:
  We derive the Deep Inelastic anti-quark distribution in a baryon at a low
value of Q^2 using the variational principle of Quantum HadronDynamics, an
alternative formulation of Quantum ChromoDynamics. It is determined by a
variational approach generalizing the ``valence'' quark approximation of
earlier papers. We find that the ``primordial'' anti-quarks carry less than a
percent of the baryon momentum. In the limit of chiral symmetry and N_c to
infinity, we show that the anti-quark content of the proton vanishes at low Q^2


title:
Two-Body Decays of the Lightest Stop in Supergravity with and without
  R-Parity

abstract:
  We study the decays of the lightest top squark in supergravity models with
and without R-parity. Using the simplest model with an effective explicit
bilinear breaking of R-parity and radiative electroweak symmetry breaking we
show that, below the threshold for decays into charginos $\tilde t_1\to
c\chi^+_1$, the lightest stop decays mainly into third generation fermions,
$\tilde t_1\to b\tau$ instead of the R-parity conserving mode $\tilde t_1\to
c\chi^0_1$, even for tiny tau--neutrino mass values. Moreover we show that,
even above the threshold for decays into charginos, the decay $\tilde t_1\to
b\tau$ may be dominant. We study the role played by the universality of the
boundary conditions on the soft supersymmetry breaking terms. This new decay
mode $\tilde t_1\to b\tau$ as well as the cascades originated by the
conventional $\tilde t_1\to c\chi^0_1$ decay followed by the R-parity violating
neutralino decays can provide new signatures for stop production at LEP and the
Tevatron.


title:
QCD vacuum tensor susceptibility and properties of transversely
  polarized mesons

abstract:
  We re-estimate the tensor susceptibility of QCD vacuum, $\chi $, and to this
end, we re-estimate the leptonic decay constants for transversely polarized
$\rho $- ,~$\rho'$- and b_1-mesons. The origin of the susceptibility is
analyzed using duality between $\rho$- and b_1- channels in a 2-point
correlator of tensor currents. We confirm the results in Nucl.Phys.
B283(1987)706 for the 2-point correlator of tensor currents and disagree with
Phys.Lett. B395(1997)307 on both OPE expansion and the value of QCD vacuum
tensor susceptibility. Using our value for the latter we determine new
estimations of nucleon tensor charges related to the first moment of the
transverse structure function h_1 of a nucleon.


title:
CompHEP - a package for evaluation of Feynman diagrams and integration
  over multi-particle phase space. User's manual for version 33

abstract:
  CompHEP is a package for automatic calculations of elementary particle decay
and collision properties in the lowest order of perturbation theory (the tree
approximation). The main idea prescribed into the CompHEP is to make available
passing on from the Lagrangian to the final distributions effectively with a
high level of automation.


title:
Predictions of ZFITTER v.6 for fermion-pair production with
  acollinearity cut

abstract:
  ZFITTER is a Fortran package for the description of fermion-pair production
in e+e- annihilation. We report on results of a rederivation of the complete
set of analytical O(alpha) formulae for the treatment of photonic corrections
to the total cross-section and the integrated forward-backward asymmetry with
combined cuts on acollinearity angle, acceptance angle, and minimal energy of
the fermions. Numerically, the following changes result in ZFITTER v. 6.11
compared to ZFITTER v. 5.20/21: (i) at the Z resonance -- numerical changes are
negligible; (ii) at LEP 1 energies off-resonance -- corrections amount to at
most few per mil; (iii) at LEP 2 energies -- corrections amount to one per cent
or less. Thus, the predictions for LEP/SLC data remain unchanged within the
actual errors.


title: QCD at Finite Density and Color Superconductivity

abstract: Brief review of current status of the field.


title:
Weak Radiative Decay Lambda_b to Lambda gamma and Quark-Confined Effects
  in the Covariant Oscillator Quark Model

abstract:
  Motivated by the observation of the decay B to K* gamma by the CLEO
collaboration, we have systematically analyzed the weak radiative decay
Lambda_b to Lambda gamma, evaluating the confined effects of quarks in the
covariant oscillator quark model. This decay process receives both short
distance (electromagnetic penguins at the one loop level) the long distance
contributions in the quark level. The long distance contributions are analyzed
using the vector meson dominance (VMD) method. The estimated branching ratio is
found to be 0.23 times 10^-5.


title: Physics of the Power Corrections in QCD

abstract:
  We review the physics of the power corrections to the parton model. In the
first part, we consider the power corrections which characterize the infrared
sensitivity of Feynman graphs when the contribution of short distances
dominates. The second part is devoted to the hypothetical power corrections
associated with nonperturbative effects at small distances.


title: Power Corrections from Small Distances

abstract:
  We review recent speculations on power like corrections in QCD which go
beyond the standard Operator Product Expansion. Both the theoretical picture
underlying these corrections and phenomenological manifestations are discussed
in some detail.


title:
An $SU(2)_{L}\times U(1)_{Y} \times S_{3} \times D$ model for
  atmospheric and solar neutrino deficits

abstract:
  Motivated by the recent Super-Kamiokande experiment on atmospheric and solar
neutrino oscillation we propose a see-saw model of three generations of
neutrinos based on the gauge group $SU(2)_{L}\times U(1)_{Y}$ with discrete
symmetries $(S_{3} \times D)$ and three right handed singlet neutrinos so that
this model can accommodate the recent Super-Kamiokande data on atmospheric and
solar neutrino oscillations. The model predicts maximal mixing between
$\nu_{\mu}$ and $\nu_{\tau}$ with $sin^{2}2{\theta_{\mu\tau}}$ = 1 as required
by the atmospheric neutrino data and small mixing between $\nu_{e}$ and
$\nu_{\mu}$ with $sin^{2}2{\theta_{e\mu}} \sim (10^{-2}-10^{-3})$ as a possible
explanation of the solar neutrino deficit through the MSW mechanism. The model
admits two mass scales of which one breaks the electroweak symmetry and the
other is responsible for the breaking of the lepton number symmetry at GUT
scale leading to small Majorana mass of the left handed doublet neutrinos.


title:
The minimum supersymmetric standard model without R-parity through
  various lepton-number violations

abstract:
  The minimum supersymmetric standard model (MSSM) without R-parity through
various lepton-number violations is investigated systematically. All kinds of
possible mixing in the model are formulated precisely. The remarkable issue
that the lightest `Higgs' $H_1^0$ may be heavier than the weak-boson $Z$ at
tree level is kept, as the special R-parity violation MSSM where only bilinear
violation of the lepton numbers is allowed. It is also shown explicitly that
there is a freedom $U(n+1)$ ($n$ is the number of the broken lepton-numbers) in
re-defining the lepton and Higgs superfields. Feynman rules relevant to the
R-parity violations are given precisely in $'$t Hooft-Feynman gauge. With
further assumptions and concerning all available experimental constraints,
spectrum for interest sectors is computed numerically.


title:
Constraining Extensions of the Quark Sector with the CP Asymmetry in
  $B\to \psi K_{S}$

abstract:
  Models with extended quark sector affect the CP asymmetry in the $B\to \psi
K_{S}$ decay, $a_{\psi K_{S}}$, in two ways: First, the top-mediated box
diagram is not necessarily the only important contribution to $B-\bar{B}$
mixing. Second, the $3\times 3$ CKM matrix is no longer unitary. We analyze the
constraints that follow from the CDF measurement, $a_{\psi K_{S}}
=0.79^{+0.41}_{-0.44}$, on the mixing parameters of extended quark sectors.
Most noticeably, we find significant constraints on the phase of the relevant
flavor changing $Z$ coupling in models with extra down quarks in vector-like
representations. Further implications for the CP asymmetry in semileptonic $B$
decays are discussed.


title:
Large rescaling of the scalar condensate, towards a Higgs-gravity
  connection ?

abstract:
  In the Standard Model the Fermi constant is associated with the vacuum
expectation value of the Higgs field $<\Phi>$, `the condensate', usually
believed to be a nearly cut-off independent quantity. General arguments related
to the `triviality' of $\lambda\Phi^4$ theory in 4 space-time dimensions
suggest, however, a dramatic renormalization effect in the continuum theory.
This effect is visible on the relatively large lattices (such as $32^4$)
available today. The result is suggestive of a certain `Higgs-gravity
connection', as discussed some years ago. The space-time structure is
determined by symmetry breaking and the Planck scale is essentially a rescaling
of the Fermi scale. The resulting picture may lead to quite substantial changes
in the usual phenomenology associated with the Higgs particle.


title: Constraints on $s\to d \gamma$ from Radiative Hyperon and Kaon Decays

abstract:
  The quark-level process $b \to s \gamma$ has been used extensively to place
constraints on new interactions. These same interactions can be further
constrained from the enhancement they induce in the quark-level $s \to d
\gamma$ transition, to the extent that the short distance contributions can be
separated from the long distance contributions. We parameterize what is known
about the long distance amplitudes and subtract it from the data in radiative
hyperon and kaon decays to constrain new interactions.


title:
Four Fermion Contact Terms in Charged Current Processes and Large Extra
  Dimensions

abstract:
  We study the bounds that can be obtained on four-fermion contact terms from
the experimental data for (e+ p -> \bar{nu} X) obtained at HERA and (p \bar{p}
-> e \nu), measured at TEVATRON. We compare these bounds with the ones
available in the literature. Finally, we apply these results to study the
compactification radius in theories with large extra dimensions and we obtain
the bound M_c >= 3.3 TeV.


title: Naturally Large Cosmological Neutrino Asymmetries in the MSSM

abstract:
  A large neutrino asymmetry is an interesting possibility for cosmology, which
can have significant observable consequences for nucleosynthesis and the cosmic
microwave background. However, although it is a possibility, there is no
obvious reason to expect the neutrino asymmetry to be observably large. Here we
note that if the baryon asymmetry originates via the Affleck-Dine mechanism
along a d=4 flat direction of the MSSM scalar potential and if the lepton
asymmetry originates via Affleck-Dine leptogenesis along a d=6 direction,
corresponding to the lowest dimension directions conserving R-parity, then the
ratio n_{L}/n_{B} is naturally in the range 10^{8}-10^{9}. As a result, a
potentially observable neutrino asymmetry is correlated with a baryon asymmetry
of the order of 10^{-10}.


title: Topological structure of chiral QCD vacuum

abstract:
  Using the trace anomaly relation, low-energy theorem and Witten-Veneziano
formula, we have developed an analytical formalism which allows one to
calculate the gluon condensate, the topological susceptibility and the mass of
the $\eta'$ meson in the chiral limit as functions of the non-perturbative
vacuum energy density. It is used for numerical evaluation of the chiral QCD
topology within the QCD vacuum model consisting mainly of the quantum component
given by the recently proposed zero modes enhancement (ZME) model and the
classical component given by the the random instanton liquid model (RILM). We
sum up both contributions into the total, nonperturbative vacuum energy
density. A very good agreement with the phenomenological values of the
topological susceptibility, the mass of the $\eta'$ meson in the chiral limit
and the gluon condensate has been obtained. This puts the above mentioned QCD
vacuum model on a firm phenomenological ground.


title: Triviality of the quark propagator in the ladder approximation in QCD

abstract:
  The validity of the ladder approximation (LA) in QCD and QED in the context
of the corresponding Schwinger-Dyson (SD) equations and Slavnov-Taylor (ST) and
Ward-Takahashi (WT) identities is investigated. In contrast to QED, in QCD
bacause of color degrees of freedom the summation of the ladder diagrams within
the Bethe-Salpeter (BS) integral equation for the quark-gluon vertex at zero
momentum transfer on account of the corresponding ST identity does provide an
an addition constraint on the quark SD equation itself. Moreover, the solution
of the constraint equation requires the full quark propagator should be almost
trivial (free-type) one, i. e. there is nontrivial quark propagator in the LA
in QCD. This triviality results in the fact that the standard LA ignores the
self-interaction between gluons caused by color charges (non-Abelian character
of QCD).


title:
Charm Contribution to the Structure Function in Diffractive Deep
  Inelastic Scattering

abstract:
  The charm contribution to the structure functions of diffractive deep
inelastic scattering is considered here within the context of the
Ingelman-Schlein model. Numerical estimations of this contribution are made
from parametrizations of the HERA data. Influence of the Pomeron flux factor is
analized as well as the effect of the shape of the initial parton distribution
employed in the calculations. The obtained results indicate that the charm
contribution to diffractive deep inelastic process might be large enough to be
measured in the HERA experiments.


title: New representation for the odderon wave function

abstract:
  New representation of the odderon wave function is derived, which is
convergent in the whole impact parameter plane and provides the analytic form
of the quantization condition for the integral of motion q_3. A new quantum
number, triality, is identified. This, together with the choice of the
conformal basis, allows for simple calculation of eigenvalues of a wide class
of operators.


title: Anomalous U(1)'s and Proton Stability in Brane Models

abstract:
  We consider the most general generation-independent U(1) gauge symmetry
consistent with the presence of Yukawa couplings for all quarks and leptons in
the SUSY version of the Standard Model. This U(1) has generically mixed
anomalies with SM groups, which cannot be cancelled by the Green-Schwarz
mechanism of heterotic D=4 strings. We argue that these anomalies can in
principle be cancelled by the generalized Green-Schwarz mechanism present in
field theories corresponding to D-branes at singularities. Moreover, unlike the
heterotic case, once the U(1) symmetry is broken it may remain as an exact
perturbative global symmetry in the low energy theory. Applying this scheme to
the SUSY SM we find that gauging such a general U(1):1) B and L violating
operators at least up to dim=3,4,5,6 are generically forbidden; 2)The
$\mu$-term is generically supressed. We also study the properties of a U(1)
symmetry whose mixed anomalies with the different SM gauge groups are in the
ratio of the beta function coefficients $\beta_a$. This relation has been shown
to hold in certain orientifold models. In all cases the U(1) remains as a
global symmetry at the orientifold singularity, the SM Higgs can break it at
the electroweak scale, making possible to relate the blowing-up of the
singularity with electroweak symmetry breaking.


title:
Rescattering and electroweak penguin effects in determinations of the
  weak phase $\gamma$

abstract:
  Determinations of the CKM phase $\gamma$ from weak nonleptonic $B$ decays are
affected by electroweak (EW) penguins and rescattering effects. In this talk it
is explained how the EW penguin effects can be controlled with the help of
SU(3) symmetry, by relating them to tree-level amplitudes. The impact of the
final-state interactions on the determination of $\gamma$ from $B^+\to K\pi$
decays is studied numerically, showing that they can be important. A few
alternative methods are discussed which use additional decays to eliminate
their effects.


title: Subjet Rates in Hadron Collider Jets

abstract:
  We calculate the subjet rates for jets produced in hadron collisions. The kt
algorithm is used to define the jets and allows the theoretical calculation to
sum both the leading and next-to-leading logarithms in the resolution variable,
ycut. We also ensure that our calculation matches exactly the leading order in
alpha_s result and has sensible behaviour near thresholds.


title: Flavor changing models with strictly massless neutrinos

abstract:
  Theoretical models which present flavor changing neutrino interactions and
simultaneously prevent this particle from acquiring any mass exist. We discuss
some of them and their predictions for neutrino oscillations in matter which
can account for the solar neutrino anomaly as well as the zenith-angle
dependence of the deficit of atmospheric neutrinos observed by the
SuperKamiokande experiment without invoking, therefore, neutrino masses nor
mixing.


title: Multi-TeV Scalars are Natural in Minimal Supergravity

abstract:
  For a top quark mass fixed to its measured value, we find natural regions of
minimal supergravity parameter space where all squarks, sleptons, and heavy
Higgs scalars have masses far above 1 TeV and are possibly beyond the reach of
the Large Hadron Collider at CERN. This result is simply understood in terms of
``focus point'' renormalization group behavior and holds in any supergravity
theory with a universal scalar mass that is large relative to other
supersymmetry breaking parameters. We highlight the importance of the choice of
fundamental parameters for this conclusion and for naturalness discussions in
general.


title:
Magnetic Interactions, the Renormalization Group and Color
  Superconductivity in High Density QCD

abstract:
  We investigate the effect of long range magnetic interactions on the
renormalization group (RG) evolution of local Cooper pairing interactions near
the Fermi surface in high density QCD. We use an explicit cut-off on momentum
modes, with special emphasis on screening effects such as Landau damping, to
derive the RG equations in a gauge invariant, weak coupling expansion. We
obtain the Landau pole $\Delta \sim \mu g^{-5} \exp(- \frac{3 \pi^2}{\sqrt{2}
g})$, although the structure of our equations differs from previous results. We
also investigate the gap equation, including condensates of higher angular
momentum. We show that rotational invariance is unbroken at asymptotically high
density, and verify that $\Delta$ is the correct value of the gap when higher
modes are included in the analysis.


title:
Variations of the Neutralino Elastic Cross-Section with CP Violating
  Phases

abstract:
  We analyze the neutralino-nucleus elastic cross-section in the MSSM,
including contributions from CP-violating phases, using the four-fermi
neutralino-quark interaction. Over a wide range of the MSSM parameter space we
show the variations in the cross-sections due to these phases. We further
concentrate on the regions which are consistent with constraints from the
electric dipole moment of the electron, neutron and mercury atom. In the
regions we examine in detail, we find suppressions by up to a factor of two,
while enhancements in the cross-sections are no greater than $\sim$ 10%.


title: High Precision Test of QCD at Beijing Electron Positron Collider

abstract:
  The generalized Crewther relation relates the cross section ratio
$R=\sigma(e^+e^- \to {\rm hadrons})/\sigma(e^+e^- \to {\mu}^+ {\mu}^-)$ in
$e^+e^-$ annihilation with the Bjorken sum rule or the Gross-Llewellyn Smith
sum rule in deep inelastic scattering and provides a fundamental connection for
observables in Quantum Chromodynamics (QCD) without scale or scheme
ambiguities. The ratio $R$ can be measured at the upgrated Bejing Electron
Positron Collider or the $\tau$-Charm factory with higher precision and thus
can be served for a high precision test of QCD in the Standard Model.


title: Solar Neutrinos and the Eclipse Effect

abstract:
  The solar neutrino counting rate in a real time detector like
Super--Kamiokanda, SNO, or Borexino is enhanced due to neutrino oscillations in
the Moon during a partial or total solar eclipse. The enhancement is calculated
as a function of the neutrino parameters in the case of three flavor mixing.
This enhancement, if seen, can further help to determine the neutrino
parameters.


title: Instanton-Induced Interactions in Finite Density QCD

abstract:
  We consider the finite density, zero-temperature behaviour of quark matter in
the instanton picture. Since the instanton-induced interactions are attractive
in both $\bar{q}q$ and $qq$ channels, a competition ensues between phases of
matter with condensation in either or both. It results in chiral symmetry
restoration due to the onset of diquark condensation, a `colour
superconductor', at finite density.