title: Invariant Box-Parameterization of Neutrino Oscillations

abstract:
  The model-independent "box" parameterization of neutrino oscillations is
examined. The invariant boxes are the classical amplitudes of the individual
oscillating terms. Being observables, the boxes are independent of the choice
of parameterization of the mixing matrix. Emphasis is placed on the relations
among the box parameters due to mixing--matrix unitarity, and on the reduction
of the number of boxes to the minimum basis set. Using the box algebra, we show
that CP-violation may be inferred from measurements of neutrino flavor mixing
even when the oscillatory factors have averaged. General analyses of neutrino
oscillations among $n\ge 3$ flavors can readily determine the boxes, which can
then be manipulated to yield magnitudes of mixing matrix elements.


title: Valence QCD: Connecting QCD to the Quark Model

abstract:
  A valence QCD theory is developed to study the valence quark properties of
hadrons. To keep only the valence degrees of freedom, the pair creation through
the Z graphs is deleted in the connected insertions; whereas, the sea quarks
are eliminated in the disconnected insertions. This is achieved with a new
``valence QCD'' lagrangian where the action in the time direction is modified
so that the particle and antiparticle decouple. The theory has the vector and
axial $U(2N_F)$ symmetry in the particle-antiparticle space. Through lattice
simulation, it appears that this is dynamically broken down to $U_q(N_F) \times
U_{\bar{q}}(N_F)$. Furthermore, the lattice simulation reveals spin degeneracy
in the hadron masses and SU(6) relations in the ratios of $F_A/D_A, F_S/D_S$,
and $\mu^n/\mu^p$. This leads to an approximate $U_q(2N_F) \times
U_{\bar{q}}(2N_F)$ symmetry which is the basis for the valence quark model. We
find that the masses of N, $\Delta, \rho, \pi, a_1$, and $a_0$ all drop
precipitously compared to their counterparts in the quenched QCD calculation.
This is interpreted as due to the disapperance of the `constituent' quark mass
which is dynamically generated through tadpole diagrams. Form the near
degeneracy between N and $\Delta$ for the quark masses we have studied (ranging
from one to four times the strange mass), we conclude that the origin of the
hyper-fine splitting in the baryon is largely attibuted to the Goldstone boson
exchanges between the quarks. These are the consequences of lacking chiral
symmetry in valence QCD. We discuss its implication on the models of hadrons.


title:
Constraints on Neutrino Mixing from r-process Nucleosynthesis in
  Supernovae

abstract:
  In this paper we note that for neutrino mass squared differences in the range
$10^{-4} - 10^{-1} eV^2$, vacuum neutrino oscillations can take place between
the neutrino-sphere and the weak freeze-out radius in a type II supernova.
Requiring that such oscillations are consistent with the r-process
nucleosynthesis from supernovae one can constrain the mixing of $\nu_e$ with
$\nu_{\mu}$ (or $\nu_\tau$) down to $10^{-4} eV^2$. We first do a two-flavor
study and find that the neutron rich condition $Y_e < 0.5$ is satisfied for all
values of mixing angles. However if we take the criterion $Y_e < 0.45$ for a
successful r-process and assume $\nu_\mu - \nu_e$ oscillations to be operative
then this mode as a possible solution to the atmospheric neutrino anomaly is
ruled out in accordance with the recent CHOOZ result. Furthermore since we can
probe mass ranges lower than CHOOZ the narrow range that was allowed by the
CHOOZ data at 99% C.L. is also ruled out. Next we do a three-generation
analysis keeping $\Delta m_{12}^2 \sim 10^{-5} eV^2$ or $10^{-11} eV^2$ (solar
neutrino range) and $\Delta m_{13}^2 \approx \Delta m_{23}^2 \sim 10^{-4} -
10^{-1} eV^2$ (atmospheric neutrino range) and use the condition $Y_e < 0.45$
to give bounds on the mixing parameters and compare our results with the CHOOZ
bound. We also calculate the increase in the shock-reheating obtained by such
oscillations.


title:
Perturbative QCD description of multiparticle correlations in quark and
  gluon jets

abstract:
  The QCD evolution equations in Modified Leading Log Approximation for the
factorial moments of the multiplicity distribution in quark and gluon jets are
numerically solved with initial conditions at threshold by fully taking into
account the energy conservation law. After applying Local Parton Hadron Duality
as hadronization prescription, a consistent quantitative description of
available experimental data for factorial cumulants and factorial moments of
arbitrary order and for their ratio both in quark and gluon jets and in
$e^+e^-$ annihilation is achieved.


title:
Broken R Parity Contributions to Flavor Changing Rates and CP
  Asymmetries in Fermion Pair Production at Leptonic Colliders

abstract:
  We examine the effects of the R parity odd renormalizable interactions on
flavor changing rates and CP violation asymmetries in the production of
fermion-antifermion pairs at $e^-- e^+$ leptonic colliders. The produced
fermions may be leptons, down-quarks or up-quarks, and the center of mass
energies may range from the Z-boson pole up to $ 1000$ GeV. Off the Z-boson
pole, the flavor changing rates are controlled by tree level amplitudes and the
CP asymmetries by interference terms between tree and loop level amplitudes. At
the Z-boson pole, both observables involve loop amplitudes. The lepton number
violating interactions, associated with the coupling constants, $\l_{ijk},
\l'_{ijk}$, are only taken into account. The consideration of loop amplitudes
is restricted to the photon and Z-boson vertex corrections. We briefly review
flavor violation physics at colliders. We present numerical results using a
single, species and family independent, mass parameter, $\tilde m$, for all the
scalar superpartners and considering simple assumptions for the family
dependence of the R parity odd coupling constants.


title: Cherenkov radiation of magnon and phonon by the slow magnetic monopole

abstract:
  The Cherenkov radiation of magnons at passage of the heavy slow magnetic
monopole through an ordered magnetic matter is considered. Also the Cherenkov
radiation of phonons at monopole movement in medium is discussed.


title: Relation between quark masses and weak mixings

abstract:
  Simple transformation formulas between fermion matrices and observables, and
numerical values of quark matrices, are obtained on a particular weak basis
with one quark matrix diagonal and the other with vanishing elements 1-1, 1-3
and 3-1, and with only the element 2-2 complex. When we choose $M_u$ diagonal,
then $M_d$ shows intriguing numerical properties which suggest a four parameter
description of it, which implies $V_{us}\simeq \sqrt{m_d/m_s}$, $V_{cb}\simeq
(3/\sqrt{5})(m_s/m_b)$ and $V_{ub}\simeq (1/\sqrt{5})(\sqrt{m_d m_s}/m_b)$. Few
comments on mass-mixing relations are added.


title: QCD Tests in High Energy Collisions

abstract:
  Recent measurements and theoretical developments on the hadronic final state
in deep-inelastic scattering, pp and ee collisions are presented.


title: Intermittency in Individual Events

abstract:
  Recent discussion of the possibility to study intermittency in individual
events of high multiplicity by A. Bialas and myself is reported. In the
framework of $\alpha-$model it is found that, for a cascade long enough, the
dispersion of intermittency exponents obtained from individual events is fairly
small. This fact opens the possibility to study the distribution of the
intermittency parameters characterizing the cascades seen (by observing
intermittency) in particle spectra.


title: gamma nu -> gamma gamma nu and crossed processes at energies below m_W

abstract:
  The cross sections for the processes $\gamma \nu\to \gamma \gamma \nu$,
$\gamma\gamma\to\gamma\nu\bar{\nu}$ and $\nu\bar{\nu}\to\gamma\gamma\gamma$ are
calculated for a range of center of mass energies from below $m_e$ to
considerably above $m_e$, but much less than $m_W$. This enables us to treat
the neutrino--electron coupling as a four--Fermi interaction and results in
amplitudes which are electron box diagrams with three real photons and one
virtual photon at their vertices. These calculations extend our previous
low--energy effective interaction results to higher energies and enable us to
determine where the effective theory is reliable.


title: Two-Loop Chiral Perturbation Theory and the Pion-Pion Phase Shifts

abstract:
  We want to test the predictive power of Chiral Perturbation Theory (ChPT). In
this work, we use the ChPT pion-pion scattering amplitude, including two loop
contributions, and we obtain S- and P-wave low-energy phase shifts. We show
that, by varying just one free parameter, the resulting S- and P-wave phase
shifts are in reasonable agreement with the experimental data.


title: The CP Conserving Contribution to $K_L\to\pi^0\nu\bar\nu$

abstract:
  The rare decay $K_L\to\pi^0\nu\bar\nu$ is dominated by direct CP violation
and can be computed with extraordinarily high precision. In principle also a CP
conserving contribution to this process can arise within the Standard Model. We
clarify the structure of the CP conserving mechanism, analyzing both its
short-distance and long-distance components. It is pointed out that the
calculation of the CP conserving amplitude, although sensitive in part to
nonperturbative physics, is rather well under control. The resulting CP
conserving contribution to the rate for $K_L\to\pi^0\nu\bar\nu$ turns out to be
very strongly suppressed due to several factors, which we discuss in detail.


title: Sum Rules and Positivity Constraints on Nucleon Spin Structure

abstract:
  The spin structure of nucleon at twist 2 and 3 levels is analyzed. The
contribution of quark and gluon spins to nucleon spin are Lorentz invariant,
while it is not sure for orbital angular momentum. The conserved fractional
moments of transversity distribution are considered. The scenario of decoupled
total angular momentum, determined predominantly by the unpolarized scattering,
is discussed.


title: QCD Spectra and Random Matrix Models

abstract:
  We summarize some recent results on the application of macroscopic spectral
properties of random matrix models (RMM) to the QCD spectra. A comparison to
existing lattice simulation is presented both for staggered and Wilson fermions
for high but finite temperature. We consider two type of mixing between the
four lowest Matsubara modes, corresponding to third and fifth order algebraic
equation for the pertinent resolvent, respectively.


title:
The search for charged sleptons and flavour lepton number violation at
  LHC (CMS)

abstract:
  We study a possibility to detect charged sleptons and flavour lepton number
violation at LHC (CMS). We investigate the production and decays of right- and
left-handed sleptons separately. We have found that for luminosity L = 10**5
1/pb it would be possible to detect right-handed sleptons with a mass up to 325
GeV and left-handed ones with a mass up to 350 GeV. We also investigate a
possibility to look for flavour lepton number violation in slepton decays due
to the mixing of different slepton generations. We find that for the maximal
(smu_R - se_R) mixing it is possible to detect such effect for sleptons with a
mass up to 250 GeV.


title:
Bilinear R-parity Violation and $\tau^{\mp} \tilde{\kappa}^{\pm}$ mixing
  production in e^+ e^- colliders

abstract:
  A R-parity breaking SUSY model characterized by an effective bilinear
violation with only $\tau$-lepton number breaking in the superpotential is
outlined. The CP-odd Higgs boson masses and those of charged Higgs bosons are
discussed. In the model, several interesting mass mixings else such as the
mixing between $\tau$ lepton and charginos etc in the model are discussed too.
Being one of example, we have computed the mixing production $e^{+} e^{-} \to
\tau^{\mp} \tilde{\kappa}^{\pm}_{i} (i=1,2)$ in e^+ e^- colliders, where
$\tau^{\mp}, \tilde{\kappa}^{\pm}_{i}(i=1,2)$ denote the physical $\tau$ lepton
and charginos.


title: Axion Hunting at the Turn of the Millenium

abstract:
  The status of several current and proposed experiments to search for galactic
dark-matter and solar axions is reviewed in the light of astrophysical and
cosmological limits on the Peccei-Quinn scale.


title: Faddeev Null Plane Model of Proton

abstract:
  The proton is formulated as a relativistic system of three constituent quarks
interacting via a zero-range two-body force in the null-plane. The covariance
of the null-plane Faddeev-like equation under kinematical front-form boosts is
discussed. A simplified three-boson model of the nucleon wave-function is
obtained numerically. The proton electric form-factor reproduces the
experimental data for low momentum transfers and qualitatively describes the
asymptotic region.


title: Relativistic Bound States in 2+1 and 1+1 Dimensions in the Null-Plane

abstract:
  The Relativistic formulation of the three-boson model interacting via a
zero-range two-body force in the null-plane is given in 2+1 and 1+1 space-time
dimension. The bound state energy is calculed as function of the two-body boson
binding energy.


title: The Phase Diagram of QCD

abstract:
  We show that current experimental knowledge of QCD together with general
model independent arguments such as continuity, universality and thermodynamic
relations, as well as the information gained from various models can be used to
constrain the phase diagram of QCD as a function of temperature and baryon
chemical potential.


title: The Validity of Charge Symmetry for Parton Distributions

abstract:
  Recent measurements of the Gottfried sum rule have focused attention on the
possibility of substantial flavor symmetry breaking in the proton sea. This is
confirmed by pp and pD Drell-Yan processes measured at FNAL. Theoretical models
used to `prove' flavor symmetry breaking rely on the assumption of charge
symmetric parton distributions. Substantial charge symmetry violation [CSV]
could affect current tests of flavor symmetry. In this review we examine the
possibility of CSV for parton distributions. We first give definitions for
structure functions without making the usual assumption of charge symmetry.
Next we make estimates of CSV for both valence and sea quark distributions. We
list a set of relations which must hold if charge symmetry is valid, and review
current experimental limits on CSV. We propose a series of experimental tests
of charge symmetry. These tests could either detect CSV, or they could provide
stronger upper limits on CSV effects. We discuss CSV contributions to sum
rules, and we propose sum rules which could differentiate between flavor
symmetry, and charge symmetry violation in nuclear systems.


title: Long-Range Correlations in Deep-Inelastic Scattering

abstract:
  Multiplicity correlations between the current and target regions of the Breit
frame in deep-inelastic scattering processes are studied. It is shown that the
correlations are sensitive to the first-order perturbative QCD effects and can
be used to extract the behavior of the boson-gluon fusion rates as a function
of the Bjorken variable. The behavior of the correlations is derived
analytically and analyzed using a Monte Carlo simulation.


title:
Hanbury Brown - Twiss Interferometry in High Energy Nuclear and Particle
  Physics

abstract:
  I review recent applications of two-particle intensity interferometry in high
energy physics, concentrating on relativistic heavy ion collisions. By
measuring hadronic single-particle spectra and two-particle correlations in
hadron-hadron or heavy-ion collisions, the size and dynamical state of the
collision fireball at freeze-out can be reconstructed. I discuss the relevant
theoretical methods and their limitations. By applying the formalism to recent
pion correlation data from Pb+Pb collisions at CERN we demonstrate that the
collision zone has undergone strong transverse growth before freeze-out (by a
factor 2 in each direction), and that it expands both longitudinally and
transversally. From the thermal and flow energy density at freeze-out the
energy density at the onset of transverse expansion can be estimated from
conservation laws. It comfortably exceeds the critical value for the transition
to color deconfined matter.


title:
Bounds on Transverse Spin Asymmetries for Lambda Baryon Production in pp
  Collisions at BNL RHIC

abstract:
  We study inclusive Lambda hyperon production in pp collisions at BNL RHIC,
with just one transversely polarized proton. We show that the measurement of
the spin transfer between the initial proton and the produced Lambda is
sensitive to the proton transversity distributions and to the corresponding
Lambda transversity fragmentation functions. In view of our present ignorance
of these distributions and fragmentation functions, we resort to positivity
bounds for making some predictions for the corresponding spin transfer
asymmetry.


title: Renormalisation of the Nonperturbative Thermal Pressure

abstract:
  We show how the fully resummed thermal pressure is rendered ultraviolet
finite by standard zero-temperature renormalisation. The analysis is developed
in a 6-dimensional scalar model that mimics QED and has $N$ flavours. The
$N\to\infty$ limit of the model can be calculated completely. At a critical
temperature, one of the degrees of freedom has vanishing screening mass like
the transverse gauge bosons in four-dimensional finite-temperature perturbation
theory. The renormalised nonperturbative interaction pressure of this model is
evaluated numerically.


title: Anomalous interactions in Higgs boson production at photon colliders

abstract:
  We discuss the potentialities of the non-standard interaction study via the
Higgs boson production at photon ($\ggam$ and $e\gamma$) colliders. We estimate
the scale of New Physics phenomena beyond the standard model that can be seen
in the experiments with Higgs boson production. In particular, the effect of
new heavy particles within the standard model is shown to be quite observable.


title:
Universal Seesaw Mass Matrix Model with Three Light Pseudo-Dirac
  Neutrinos

abstract:
  A universal seesaw mass matrix model, which gives successful description of
quark mass matrix in terms of lepton masses, yields three "sterile" neutrinos
\nu^s_{i}, which compose pseudo-Dirac neutrinos \nu_{i\pm}^{ps}\simeq (\nu_{i}
\pm \nu^s_{i})/\sqrt{2} together with the active neutrinos \nu_{i}
(i=e,\mu,\tau). The solar and atmospheric neutrino data are explained by the
mixings \nu_{e}\leftrightarrow \nu^s_{e} and \nu_{\mu}\leftrightarrow
\nu^s_{\mu}, respectively. In spite of such observations of the large mixing
\sin^2 2\theta\simeq 1 in the disappearance experiments, effective mixing
parameters \sin^2 2\theta^{\alpha\beta} in appearance experiments
\nu_\alpha\to\nu_\beta (\alpha, \beta = e, \mu, \tau) are highly suppressed.


title: Summary of DIS 98

abstract:
  A personal selection is made of some of the hot topics debated at this
conference, including examples of using our knowledge of QCD to make
electroweak measurements, structure functions at low x in the light of the
corrections to the leading BFKL behaviour recently calculated, diffraction, the
existence of one or more Pomerons and whether it/they may have a well-defined
structure function, some issues in hadronic final states and polarized
structure functions, and the interesting events at large Q^2 and x and with
isolated leptons and missing transverse energy. Finally, some of the prospects
for future deep-inelastic scattering facilities are reviewed, and the
interested community is encouraged to organize itself to advocate their
approval.


title:
Model for Particle Masses, Flavor Mixing, and CP Violation Based on
  Spontaneously Broken Discrete Chiral Symmetry as the Origin of Families

abstract:
  We construct extensions of the standard model based on the hypothesis that
the Higgs bosons also exhibit a family structure, and that the flavor weak
eigenstates in the three families are distinguished by a discrete $Z_6$ chiral
symmetry that is spontaneously broken by the Higgs sector. We study in detail
at the tree level models with three Higgs doublets, and with six Higgs doublets
comprising two weakly coupled sets of three. In a leading approximation of
$S_3$ cyclic permutation symmetry the three Higgs model gives a ``democratic''
mass matrix of rank one, while the six Higgs model gives either a rank one mass
matrix, or in the case when it spontaneously violates CP, a rank two mass
matrix corresponding to nonzero second family masses. In both models, the CKM
matrix is exactly unity in leading approximation. Allowing small explicit
violations of cyclic permutation symmetry generates small first family masses
in the six Higgs model, and first and second family masses in the three Higgs
model, and gives a non-trivial CKM matrix in which the mixings of the first and
second family quarks are naturally larger than mixings involving the third
family. Complete numerical fits are given for both models, flavor changing
neutral current constraints are discussed in detail, and the issues of
unification of couplings and neutrino masses are addressed. On a technical
level, our analysis uses the theory of circulant and retrocirculant matrices,
the relevant parts of which are reviewed.


title:
The Two-Loop Finite-Temperature Effective Potential of the MSSM and
  Baryogenesis

abstract:
  We construct an effective three dimensional theory for the MSSM at high
temperatures in the limit of large-$m_{A}$. We analyse the two-loop effective
potential of the 3D theory for the case of a light right handed stop to
determine the precise region in the $m_{h}$-$m_{\tilde{t}_{R}}$ plane for which
the sphaleron constraint for preservation of the baryon asymmetry is satisfied.
We also compare with results previously obtained usind 3D and 4D calculations
of the effective potential. A two-stage phase transition still persists for a
small range of values of $m_{\tilde{t}_{R}}$. The allowed region requires a
value of $m_{\tilde{t}_{R}} \lsi m_{t}$ and $m_{h} \lsi 100$ (110) GeV for
$m_{Q} = 300$ GeV (1 TeV).


title:
Supersymmetric Left-Right Model, Automatic R-parity Conservation and
  Constraints on the $W_R$ Mass

abstract:
  Supersymmetric left-right models with the see-saw mechanism for the neutrino
masses have the attractive property that they conserve baryon and lepton number
exactly in the Lagrangian. In this talk, I review the recent results valid for
a large class of minimal versions of the model that supersymmetry combined with
the requirement that the ground state of the model conserve electric charge
constrains the mass of the right handed $W_R$ boson to be in a certain range
i.e. $M_{W_R}\leq$ 10 TeV or $\geq 10^{10}$ GeV. In the former case (low
$M_{W_R}$), the vacuum breaks R-parity spontaneously and the latter case (high
$M_{W_R}$) is required if vacuum is to conserve R-parity. In the second case,
the effective low energy theory is the MSSM with exact R-parity, nonvanishing
neutrino masses and a pair of light doubly charged Higgs fields and their
fermionic partners. Exact R-parity conservation via see saw mechanism therefore
implies that the neutrino masses must be in the desired range to solve the
solar and atmospheric neutrino puzzles.


title: CP Asymmetries in (Semi-)Inclusive B0 Decays

abstract:
  It was recently pointed out that inclusive B^0(t) decays could show CP
violation. The totally inclusive asymmetry is expected to be tiny [O(10^{-3})]
because of large cancellations among the asymmetries in the charmless, single
charm and double charm final states. Enriching particular final state
configurations could significantly increase the CP-asymmetry and observability.
Such studies can extract fundamental CKM (Cabibbo-Kobayashi-Maskawa)
parameters, and (perhaps) even Delta m(B_s). A superb vertex detector could see
CP violation with 10^5 (10^6) flavor-tagged B_s (B_d) mesons within the CKM
model. Because the effects could be significantly larger due to new physics,
they should be searched for in existing or soon available data samples.


title: On-shell two-loop three-gluon vertex

abstract:
  The two-loop three-gluon vertex is calculated in an arbitrary covariant
gauge, in the limit when two of the gluons are on the mass shell. The
corresponding two-loop results for the ghost-gluon vertex are also obtained. It
is shown that the results are consistent with the Ward-Slavnov-Taylor
identities.


title: Model for three generations of fermions

abstract:
  A model is constructed for a chiral abelian gauge-interaction of fermions and
a potential of three higgses, so that the potential possesses a discrete
symmetry of the vacuum state, which provides the introduction of three
generations for the fermions. For the model including charged currents, a
matrix of the flavor mixing is described, and a phase giving the violation of
CP-invariance is determined. Some approximate relations connecting the values
of mixing matrix to the mass ratios for the fermions in different generations
are derived.


title: Higher order corrections to Z decay

abstract:
  Recent developments in the field of automatic computation of Feynman diagrams
using asymptotic expansions are reviewed. The hadronic decay rate of the
Z-boson is taken as an example for their physical application.


title: Generation of Magnetic Field due to Excited Q-Balls

abstract:
  We investigate phase transitions due to excited Q-balls. As excited Q-balls
have angular momentum, a magnetic field can be generated if one considers
gauged Q-balls. Based on the course of the phase transition we estimate the
strength of the magnetic field and then we find that it might be the origin of
observed magnetic fields of astrophysical objects such as galaxies and clusters
of galaxies.


title: Soft-gluon resummation for heavy quark production in hadronic collisions

abstract:
  We discuss the heavy quark production cross section near partonic threshold
in hadronic collisions, including the resummation of leading and
next-to-leading logarithms arising from soft gluon emission. We show how to
handle the complications due to the non-universal non-leading logarithms. We
give analytical results for the $q {\bar q}$ partonic subprocess and numerical
results in the DIS scheme for top quark production at the Fermilab Tevatron
where the $q {\bar q}$ channel dominates.


title:
Single particle density and density matrix from the QCD-cascade in DLA
  approximation

abstract:
  The structure of the QCD gluonic cascade in configuration space is
investigated. The explicit form of the inclusive single particle density in
configuration space transverse coordinates is derived in the double logarithmic
approximation (DLA) of QCD. The possible simplification of the multiparton
density matrix formalism for DLA approach is found and discussed.


title: Instanton-Induced Cross-Sections in Deep-Inelastic Scattering

abstract:
  We present our results for inclusive instanton-induced cross-sections in
deep-inelastic scattering, paying in particular attention to the residual
renormalization-scale dependencies. A ``fiducial'' kinematical region in the
relevant Bjorken variables is extracted from recent lattice simulations of QCD.
The integrated instanton-contribution to the cross-section at HERA
corresponding to this fiducial region is surprisingly large: It is in the
O(100) pb range, and thus remarkably close to the recently published
experimental upper bounds.


title: Supersymmetric Q-balls: theory and cosmology

abstract:
  MSSM predicts the existence of Q-balls, some of which can be entirely stable.
Both stable and unstable Q-balls can play an important role in cosmology. In
particular, Affleck-Dine baryogenesis can result in a copious production of
stable baryonic Q-balls, which can presently exist as a form of dark matter.


title: Energy and Color Flow in Dijet Rapidity Gaps

abstract:
  When rapidity gaps in high-$p_T$ dijet events are identified by energy flow
in the central region, they may be calculated from factorized cross sections in
perturbative QCD, up to corrections that behave as inverse powers of the
central region energy. Although power-suppressed corrections may be important,
a perturbative calculation of dijet rapidity gaps in ${\rm p}\bar{\rm p}$
scattering successfully reproduces the overall features observed at the
Tevatron. In this formulation, the average color content of the hard scattering
is well-defined. We find that hard dijet rapidity gaps in quark-antiquark
scattering are not due to singlet exchange alone.


title: Colour connection structure of (supersymmetric) QCD ($2\to2$) processes

abstract:
  The colour connection structure of QCD ($2\to2$) processes is discussed, with
emphasis on its application to the supersymmetric 2 parton $\to$ 2 sparton
processes, which are currently being implemented in the HERWIG Monte Carlo
event generator. The procedure described by Marchesini and Webber is found to
be inadequate, and a new method is proposed. However, this alteration is
unlikely to significantly affect the theoretical predictions for soft gluon
radiation. A complete list of supersymmetric QCD $2\to2$ matrix elements and
their colour decompositions is presented.


title: Renormalon contributions to fragmentation functions in non-singlet DIS

abstract:
  This talk discusses the power behaved corrections to fragmentation functions
for the current jet in non-singlet deep inelastic scattering. These corrections
are estimated by means of a renormalon model using a dispersive approach. The
assumption of a universal infrared finite coupling enables us to provide
quantitative estimates.


title: Resummation, Power Corrections and Prediction in Perturbative QCD

abstract:
  I give a pedagogical introduction to resummation and power corrections, using
the thrust variable in electron-positron annihilation as an example, followed
by an discussion of issues of predictability in perturbative QCD.


title: Interpreting the Atmospheric Neutrino Anomaly

abstract:
  We suggest that the atmospheric neutrino anomaly observed in the
Super-Kamiokande (and other) experiments results from the combined effects of
muon-neutrino to tau-neutrino oscillations with a Delta m^2 value of
approximately 0.4 eV^2 and oscillations between muon neutrinos and electron
neutrinos (and vice-versa) with 0.0001 < Delta m^2 < 0.001 eV^2. With an
appropriate choice of a three-neutrino mixing matrix, such a hypothesis is
consistent with essentially all neutrino observations.


title: Deeply Virtual Compton Scattering at HERA - A Probe of Asymptotia

abstract:
  We demonstrate that the measurement of an azimuthal angle asymmetry in deeply
virtual Compton scattering (DVCS) at HERA energies, is experimentally feasible
and allows one to determine for the first time the ratio $\eta$, of the real to
imaginary part of the DIS amplitude. We further show that such a measurement
would discriminate between different scenarios of the energy dependence of
$F_2(x,Q^2)$ at energies beyond those reachable at HERA.


title: QCD - looking forward

abstract:
  We outline theoretical ideas on the soft and hard dynamics of strong
high-energy interactions and discuss promising directions for future
high-energy experimental investigations including the ones which would allow
one to reveal the three-dimensional structure of QCD bound states, investigate
the onset of regime of large parton densities, and observe the violation of the
DGLAP evolution equation. We emphasize that many qualitatively new phenomena
should be present for the forward kinematics both in electron-nucleon(nucleus)
collisions at HERA and in $pp, pA$ collisions at LHC.


title: Shape functions and power corrections to the event shapes

abstract:
  We show that the leading power corrections to the event shape distributions
can be resummed into nonperturbative shape functions that do not depend on the
center-of-mass energy and measure the energy flow in the final state. In the
case of the thrust variable, the distribution is given by the convolution of
the perturbative spectrum with the shape function. Choosing the simplest ansatz
for the shape function we find that our predictions for the thrust distribution
provide a good description of the data throughout a wide range of energies.


title: Final State Interactions in Hadronic B Decays

abstract:
  I discuss the effect of final state interactions on the determination of the
CKM angle \gamma from B -> K + pi decays. Using a simple Regge-based model for
rescattering processes, I argue that such effects could be substantial enough
to make it problematic to obtain reliable limits on \gamma in this way.
Fortunately, an analysis of B -> K + K decays may provide model-independent
bounds on rescattering contributions.


title:
The Hadronic Gas Chiral Phase Transition within Generalized Chiral
  Perturbation Theory

abstract:
  We study the temperature evolution of the quark-antiquark condensate below
the chiral phase transition. The hadronic gas is described using a virial
expansion within Generalized Chiral Perturbation Theory. In such way, we can
implement both the large or small chiral condensate scenarios and analyze the
condensate dependence on the values of the lightest quark masses.


title:
The Solar Neutrino Puzzle: An Oscillation Solution with Maximal Neutrino
  Mixing

abstract:
  If, as suggested by the SuperKamiokande results, the mu neutrino and tau
neutrino are maximally and ``rapidly'' mixed, this alone determines the mapping
from current to mass eigenstates up to one rotation angle (theta) mixing the
electron neutrino ``more slowly'', with an equal combination of the mu neutrino
and tau neutrino. For sin 2 theta = 1, the resulting minimal number of free
parameters, yet maximal mixing, shows agreement between extant observations of
solar neutrinos and predictions by the standard solar model with minor
modifications.


title:
Nonperturbative renormalization and the electron's anomalous moment in
  large-alpha QED

abstract:
  We study the physical electron in quantum electrodynamics expanded on the
light-cone Fock space in order to address two problems: (1) the physics of the
electron's anomalous magnetic moment $a_e$ in nonperturbative QED, and (2) the
practical problems of ultraviolet regularization and renormalization in
truncated nonperturbative light-cone Hamiltonian theory. We present results for
$a_e$ computed in a light-cone gauge Fock space truncated to include one bare
electron and at most two photons; i.e., up to two photons in flight. The
calculational scheme uses an invariant mass cutoff, discretized light-cone
quantization (DLCQ), a Tamm--Dancoff truncation of the Fock space, and a photon
mass regulator. We introduce new weighting methods which greatly improve
convergence to the continuum within DLCQ. Nonperturbative renormalization of
the coupling and electron mass are carried out, and a limit on the magnitude of
the effective physical coupling strength is computed. A large renormalized
coupling strength $\alpha_R= 0.1$ is then used to make the nonperturbative
effects in the electron anomalous moment from the one-electron, two-photon Fock
state sector numerically detectable.


title: Fermion Masses and Mixing in 331 Models with Horizontal Symmetry

abstract:
  The possibility of adding an SU(2) horizontal symmetry to the 331 model is
studied. It is found that simple, anomaly-free fermion assignments can be made
which lead to plausible results for fermion masses and mixings. In particular,
all particles of the first generation are massless at tree-level, and the CKM
matrix acquires a realistic form.


title: Dimensionally Regularized Study of Nonperturbative Quenched QED

abstract:
  We study the dimensionally regularized fermion propagator Dyson-Schwinger
equation in quenched nonperturbative QED in an arbitrary covariant gauge using
the Curtis-Pennington vertex and perform nonperturbative renormalization
numerically. The nonperturbative fermion propagator is solved in D=4-2*epsilon
< 4 dimensional Euclidean space for a large number of values of epsilon for two
values of the coupling, alpha=0.6 and alpha=1.5. Results for D=4 are then
obtained by extrapolation to epsilon=0. We compare these results against
previous studies employing a modified ultraviolet cut-off regularization and
find agreement to within the numerical precision of the present calculations.


title: Very Light Axion

abstract: I review the idea of axion, axion properties, and the superstring axion.


title: Exploring the Light-Cone through Semi-Inclusive Hadronic Distributions

abstract:
  Light-cone dominance is established for a particular set of semi-inclusive
observables in $e^+ e^-$ hadronic annihilation. This allows to deduce, with a
certain degree of rigor, the angular distribution of hadronic energy from first
principles, without invoking quark-hadron duality.


title: Dipole Moments in Supersymmetry

abstract:
  The one-loop MSSM contributions to the weak dipole moments of the \tau lepton
and the b quark (at the Z peak) as well as the electromagnetic and weak dipole
form factors of the t quark (at arbitrary s>4m^2_t) are reviewed. Emphasis is
given to the relevance of the t-quark CP-violating weak and electric dipole
form factors as a part of the full one-loop correction to the process e^+e^-
--> t \bar{t} in the MSSM.


title: Gerasimov-Drell-Hearn sum rule and nucleon structure

abstract:
  A modification of the Gerasimov--Drell--Hearn sum rule suggested by the
current experimental data is presented. Within the conventional theoretical
framework, we find it necessary to consider the possibility of the presence of
a localized region inside a nucleon, in which the electromagnetic (EM) gauge
symmetry is spontaneous broken down, if the constraints of the gauge
invariance, Lorentz invariance and the assumption of the commutativity of the
EM charge density operator at equal-time are considered. We also discuss the
propagation of a virtual photon inside a nucleon under such a scenario. A
comment on some of the recent model independent works on the same subject is
provided.


title: On the computation of multigluon amplitudes

abstract:
  A computational algorithm based on recursive equations is developed in order
to estimate multigluon production processes at high energy hadron colliders.
The partonic reactions gg->(n-2)g with n up to n=9 are studied and comparisons
with known approximations are presented.


title: Improved Intermittency Analysis of Individual Events

abstract:
  Recent progress on the event-by-event analysis of intermittent data by R. A.
Janik and myself is reported. The intermittency analysis of single event data
(particle moments) in multiparticle production is improved, taking into account
corrections due to the reconstruction of history of a particle cascade. This
approach is tested within the framework of the $\alpha$-model.}


title:
QCD Corrections to Spin Correlations in Top Quark Production at Lepton
  Colliders

abstract:
  Spin correlations, using a generic spin basis, are investigated to leading
order in QCD for top quark production at lepton colliders. Even though, these
radiative corrections induce an anomalous gamma/Z magnetic moment for the top
quarks and allow for single, real gluon emission, their effects on the top
quark spin orientation are very small. The final results are that the top (or
anti-top) quarks are produced in an essentially unique spin configuration in
polarized lepton collisions even after including the O(alpha_{s}) QCD
corrections.


title: Neutron-Antineutron Oscillations in Nuclei Revisited

abstract:
  An upper limit on $n-\bar n$ oscillations can be obtained from the stability
of matter. This relation has been worked out theoretically and together with
data yields $\tau_{n\bar n} > (1 - 2)\times 10^8 sec$. A recent publication
claims a different relation and finds a nuclear suppression of the $n\to\bar n$
oscillations which is two orders of magnitude weaker than the previous
evaluations. Using the same approach we find, nevertheless, that the earlier
estimates are correct and conclude that future experiments with free neutrons
from reactors are capable to put a stronger limit on the $n - \bar n$
oscillation time than experiments with large amount of neutrons bound in
nuclei.


title: Challenges of Nuclear Shadowing in DIS

abstract:
  Nuclear shadowing in DIS at moderately small $x$ is suppressed by the nuclear
formfactor and depends on the effective mass of a hadronic fluctuation of the
virtual photon. We propose a solution to the problems (i) of how to combine a
definite transverse size of the fluctuation with a definite effective mass, and
(ii) of how to include the nuclear formfactor in the higher multiple scattering
terms. Comparison of the numerical results with known approximations shows a
substantial difference.


title: QCD Phenomena and the Light-Cone Wavefunction of Hadrons

abstract:
  Light-cone Fock-state wavefunctions encode the properties of a hadron in
terms of its fundamental quark and gluon degrees of freedom. A recent
experiment at Fermilab, E791, demonstrates that the color coherence and shape
of light-cone wavefunctions in longitudinal momentum fraction can be directly
measured by the high energy diffractive jet dissociation of hadrons on nuclei.
Given the proton's light-cone wavefunctions, one can compute not only the quark
and gluon distributions measured in deep inelastic lepton-proton scattering,
but also the multi-parton correlations which control the distribution of
particles in the proton fragmentation region and dynamical higher twist
effects. First-principle predictions can be made for structure functions at
small and large light-cone momentum fraction $x$. Light-cone wavefunctions also
provide a systematic framework for evaluating exclusive hadronic matrix
elements, including timelike heavy hadron decay amplitudes and form factors. In
principle, light-cone wavefunctions can be computed in nonperturbative QCD by
diagonalizing the light-cone Hamiltonian using the DLCQ method, as in
dimensionally reduced collinear QCD.


title: Pair Production of Heavy-Exotic-Fermions

abstract:
  We study the production and signatures of heavy exotic fermion pairs in the
framework of the vector singlet model (VSM), vector doublet model (VDM) and
fermion-mirror-fermion (FMF) model. We show that the pair production cross
sections are competitive with the ones for the single production of exotic
fermions due to the exchange of a photon in the $s$ channel and to the vector
component of the $Z$ - boson coupling to exotic fermions. We also exhibit some
kinematical distributions.


title:
The breaking of the flavour permutational symmetry: Mass textures and
  the CKM matrix

abstract:
  Different ansaetze for the breaking of the flavour permutational symmetry
according to S(3)L X S(3)R in S(2)L X S(2) give different Hermitian mass
matrices of the same modified Fritzsch type, which differ in the symmetry
breaking pattern. In this work we obtain a clear and precise indication on the
preferred symmetry breaking scheme from a fit of the predicted theoretical Vckm
to the experimentally determined absolute values of the elements of the CKM
matrix. The preferred scheme leads to simple mass textures and allows us to
compute the CKM mixing matrix, the Jarlskog invariant J, and the three inner
angles of the unitarity triangle in terms of four quark mass ratios and only
one free parameter: the CP violating phase Phi. Excellent agreement with the
experimentally determined absolute values of the entries in the CKM matrix is
obtained for Phi = 90 deg. The corresponding computed values of the Jarlskog
invariant and the inner angles are J = 3.00 X 10^-5, alpha= 84 deg, beta= 24
deg and gamma =72 deg in very good agreement with current data on CP violation
in the neutral kaon-antikaon system and oscillations in the B-Bbar system.


title: Mean Field, Instantons and Finite Baryon Density

abstract:
  Instantons create a non-local interaction between the quarks, which at finite
baryon density leads to the formation of a scalar diquark condensate and color
superconductivity. A mean field approach leads to a self-consistent description
of the $<\bar q q>$ and $<q q>$ condensates and shows the inevitability of a
BCS type instability at the Fermi surface. The role of the rearrangement of the
instanton ensemble for the QCD phase transitions is also discussed.


title: Where do we stand with solar neutrino oscillations?

abstract:
  We determine the neutrino parameters for MSW and vacuum oscillations (active
and sterile neutrinos) that are allowed by the separate, and collective,
imposition of the constraints from total event rates in the chlorine, GALLEX,
SAGE, and SuperKamiokande experiments (504 days), the SuperKamiokande electron
energy spectrum, and the SuperKamiokande zenith-angle dependence. The small
mixing angle MSW solution is acceptable at the 7% C.L. (8% for sterile nu's)
and the vacuum solution is acceptable at the 6% C.L. . The best-fit global MSW
solution for active neutrinos is: Delta m^2 = 5 x 10^-6 eV^2, sin^2 (2 theta) =
5.5 x 10^{-3} (and for sterile neutrinos: Delta m^2 = 4 x 10^-6 eV^2, sin^2 (2
theta) = 7 x 10^-3). For vacuum oscillations, the best-fit solution is: Delta
m^2 = 6.5 x 10^-11 eV^2, sin^2 (2 theta) = 0.75 . An arbitrary combination of
undistorted (no oscillations) pp, 7Be, 8B, and CNO neutrino fluxes is
inconsistent with the combined data sets at the 3.5 sigma C.L., independent of
astrophysical considerations. We use improved calculations of solar model
fluxes, neutrino absorption cross sections and energy spectra, and a detailed
evaluation of regeneration effects.


title: Transversity and Mass Singularities in Dimensional Regularization

abstract:
  The proton's transversity distribution will be measured at BNL's Relativistic
Heavy Ion Collider in upcoming experiments using the transverse Drell-Yan
process. Understanding the one-loop corrections is therefore important. Here,
the collinear structure in transverse Drell-Yan is investigated in detail using
dimensional regularization and the correct behaviour is found, although the
mechanism is non-trivial. The resulting n-dimensional transversity splitting
function (and consequently the one-loop transversity distribution and its
two-loop evolution) is found to be the same in both the anticommuting-gamma_5
scheme and the HVBM scheme. Alternative schemes are considered.


title: Radiative Corrections to W and Quark Propagators in the Resonance Region

abstract:
  It is shown that conventional mass renormalization, when applied to photonic
or gluonic corrections to unstable particle propagators, leads to
non-convergent series in the resonance region. A solution of this problem,
based on the concepts of pole mass and width, is presented. In contrast with
the Z case, the conventional on-shell definition of mass for W bosons and
unstable quarks contains an unbounded gauge dependence in next-to-leading
order. The on-shell and pole definitions of width are shown to coincide if
terms of O(\Gamma^2) and higher are neglected, but not otherwise.


title: Towards a Theory of Instantons at Non-zero Fermion Density

abstract:
  A formalism to study light fermions at non-zero chemical potential in the
instanton medium is presented. It is then applied to investigate chiral
symmetry restoration and diquark condensation at finite baryon density.


title:
Associated jpsi + gamma diffractive production: the nature of Pomeron
  and test of hard diffractive factorization

abstract:
  We present a study of diffractive associated jpsi + gamma production at the
Fermilab Tevatron and LHC based on the Ingelman-Schlein model for hard
diffractive scattering and the factorization formalism of NRQCD for quarkonia
production. We find that this process (p + pbar to p + jpsi + gamma + X) can be
used to probe the gluon content of the Pomeron and test the assumption of
diffractive hard scattering factorization. Using the renormalized Pomeron flux
factor D simeq 0.11 (0.052), the single diffractive jpsi + gamma production
cross section at 4<P_T< 10 GeV, -1<eta<1 region is found to be of the order of
3.0 pb (8.5 pb), the ratio of single diffractive to inclusive production is
0.50% (0.15%) in central region at the Tevatron (LHC) for the gluon fraction in
the Pomeron f_g = 0.7, independent of the values of color-octet matrix
elements.


title: Some problems in loop calculations

abstract:
  We discuss some of the problems that may occur in the calculation of
complicated Feynman diagrams. These include the group independent evaluation of
color factors, and the summation techniques that are needed for the expansion
of diagrams into their Mellin moments.


title:
Results for Precision Observables in the Electroweak Standard Model at
  Two-Loop Order and Beyond

abstract:
  Higher-order contributions to the precision observables \Delta r,
\sin^2\theta_eff and \Gamma_l are discussed. The Higgs-mass dependence of the
observables is investigated at the two-loop level, and exact results are
derived for the Higgs-dependent two-loop corrections associated with fermions.
The top-quark corrections are compared with the results obtained by an
expansion in the top-quark mass up to next-to-leading order. For the pure
fermion-loop contributions to \Delta r results up to four-loop order are
derived. They allow to investigate the validity of the commonly used
resummation of the leading fermionic contributions to \Delta r.


title: Form factors of exclusive $b\to u$ transitions

abstract:
  We present the form factors of the $B\to\pi,\rho$ transitions induced by the
$b\to u$ quark currents at all kinematically accessible $q^2$. Our analysis is
based on the spectral representations of the form factors within the
constituent quark picture: we fix the soft meson wave functions and the
constituent quark masses by fitting $A_1(q^2)$ and $T_2(q^2)$ to the lattice
results at small recoils ($17\lesssim q^2\lesssim 20 GeV^2$). We then calculate
the $B\to\pi,\rho$ transition form factors down to $q^2=0$. For the $B\to\pi$
case the region $q^2\lesssim 20 GeV^2$ however does not cover the whole
kinematically accessible range. Due to the smallness of the pion mass the
region of small recoils is close to the nearby $B^*(5234)$ resonance. We
develop a parametrization which includes the $B^*$ dominance of the form
factors $f_+$ and $f_-$ at small recoils and numerically reproduces the results
of calculations at $q^2\lesssim 20 GeV^2$. We find
$\Gamma(B\to\pi\ell\nu)=8.0^{+0.8}_{-0.2} |V_{ub}|^2 $ps$^{-1}$ and
$\Gamma(B\to\rho\ell\nu)=15.8\pm 2.3 |V_{ub}|^2 $ps$^{-1}$.


title: QCD at large and short distances (annotated version)

abstract:
  The formulation of QCD which contains no divergences and no renormalization
procedure is presented. It contains both perturbative and non-perturbative
phenomena. It is shown that, due to its asymptotically free nature, the theory
is not defined uniquely. The chiral symmetry breaking and the nature of the
octet of pseudo-scalar particles as quasi-Goldstone states are analysed in the
theory with massless and massive quarks. The U(1) problem is discussed.
  =======================================================================
  Note: The original version of the paper completed by the author in April 1997
was submitted to the hep-ph archive (hep-ph/9708424) a few days after Prof.
V.N. Gribov passed away on August 13, 1997.
  This is the first of the two papers concluding his 20 year long study of the
problem of quark confinement in QCD. In an attempt to understand the paper by a
group of his colleagues, started in November 1997 in Orsay, this annotated
version appeared. A number of misprints were eliminated, most of the equations
were checked, and some corrected. Comments have been added in order to make the
text easier to read. These comments are displayed in square brackets. Many
theorists participated in the process; the comments were assembled and the
final version prepared by Yu. Dokshitzer, C. Ewerz, A. Kaidalov, A. Mueller, J.
Nyiri and A. Vainshtein. The second paper ``The theory of quark confinement''
will soon be published.


title: $B_c$ mesons in a Bethe-Salpeter model

abstract:
  We apply our Bethe-Salpeter model for mesons to the $B_c$ family with
parameters fixed in our previous investigation. We evaluate the mass of the
pseudo-scalar $B_c$ meson as 6.356 GeV/$c^2$ and 6.380 GeV/$c^2$ and the
lifetime as 0.47 ps and 0.46 ps respectively in two reductions of the
Bethe-Salpeter Equation, in good agreement with the recently reported mass of
6.40 $\pm$ 0.39 (stat.) $\pm$ 0.13 (syst.) GeV/$c^2$ and lifetime of
$0.46^{+0.18}_{-0.16}$ (stat.) $\pm$ 0.03 (syst.) ps by the CDF Collaboration.
We evaluate the decay constant of the $B_c$ meson and compare different
contributions to its decay width.


title: Jets in hadron collisions in QCD

abstract:
  I briefly discuss three topics related to the hadroproduction of jets: jet
definitions; jet structure; and the underlying event.


title: Perturbative and nonperturbative Higgs signals

abstract:
  We discuss the current picture of the standard Higgs sector at strong
coupling and the phenomenological implications for direct searches at the LHC.


title: Family Symmetry and Neutrino Mixing

abstract:
  The observed quark hierarchies suggest a simple family symmetry. Generalized
to leptons through grand-unified quantum numbers, it produces a neutrino mixing
matrix with order-one \nu_{\mu} - \nu_{\tau} mixing, and order-\lambda^3 \nu_e
- \nu_{\mu} and \nu_e - \nu_{\tau} mixings. The intrafamily hierarchy and
observed neutrino mass differences together require this symmetry to be
anomalous, suggesting through the Green-Schwarz mechanism a string or M-theory
origin for the symmetry.


title: Pion and photon light-cone wave functions from the instanton vacuum

abstract:
  The leading-twist wave functions of the pion and the photon at a low
normalization point are calculated in the effective low--energy theory derived
from the instanton vacuum. The pion wave function is found to be close to the
asymptotic one, consistent with the recent CLEO measurements. The photon wave
function is non-zero at the endpoints. This different behavior is a consequence
of the momentum dependence of the dynamical quark mass suggested by the
instanton vacuum. We comment on the relation of meson wave functions and
off-forward parton distributions in this model.


title: Scale Dependence of Squark and Gluino Production Cross Sections

abstract:
  We investigate the choice of the renormalization and factorization scales for
the production of squarks and gluinos at the Fermilab Tevatron collider as a
function of the produced sparticle masses. We determine a scale to be used in
leading-order perturbative QCD calculations optimized such that the
normalization of the next-to-leading order cross section is reproduced. Use of
this optimal scale permits at least a partial implementation of next-to-leading
order contributions in leading order Monte Carlo simulations. We provide
next-to-leading order predictions of the production cross sections for pairs of
supersymmetric particles at the hadronic center-of-mass energy 2 TeV.


title:
Alpha_s and Gauge Coupling Unification in Flipped SU(5) Models with
  Gauge-Mediated Supersymmetry Breaking

abstract:
  We examine gauge coupling unification and prediction for $\alpha_s (M_Z)$ in
minimal flipped SU(5) with gauge-mediated supersymmetry breaking. We include
threshold corrections at weak scale, messenger scale and unification scale, and
explicitly show that in this model there can be either \emph{one-step} or
\emph{two-step} gauge coupling unification, depending on unification-scale
threshold corrections. The experimental value of $\alpha_s (M_Z)$ constrains
heavy particle masses in one-step unification. In the case of two-step
unification, we examine the prediction for $\alpha_s (M_Z)$ with two-loop,
light, messenger and heavy threshold corrections, and find it to be compatible
with the updated experimental data.


title:
Axionic Boson Stars in Magnetized Conducting Media and Monochromatic
  Radiations

abstract:
  Axions have been argued to form coherent axionic boson stars as well as
incoherent axion gas. These are ones of most plausible candidates of dark
matters. Since the axionic boson stars generate oscillating electric fields in
an external magnetic field, they induce oscillating currents in magnetized
conducting media, which result in emitting radiations. We show that colliding
with a magnetic white dwarf, an axionic boson star can emit a monochromatic
radiation with a frequency given by a mass of the axion.


title: Global vs local cosmic strings from pseudo-anomalous U(1)

abstract:
  We study the structure of cosmic strings produced at the breaking of an
anomalous U(1) gauge symmetry present in many superstring compactification
models. We show that their coupling with the axion necessary in order to cancel
the anomalies does not prevent them from being local, even though their energy
per unit length is found to diverge logarithmically. We discuss the formation
of such strings and the phenomenological constraints that apply to their
parameters.


title: The Mixing of Quarks and Leptons and Neutrino Degeneracy

abstract:
  In drawing on an analogy with the flavor mixing observed in the quark sector
we discuss a pattern of large flavor mixing angles in the lepton sector. Simple
arguments based on a democratic symmetry and its violation in the lepton sector
allow us to determine the flavor mixing matrix of leptons. The mixing angle
relevant for solar neutrino oscillations is maximal (close to $45^{\circ}$),
while the angle relevant for atmospheric neutrino oscillations is given by
$\sin^2 2 \theta = 8/9$. The emerging pattern is consistent with the results of
the solar and atmospheric neutrino experiments.


title: Oscillations of solar and atmospheric neutrinos

abstract:
  Motivated by recent results from SuperKamiokande, we study both solar and
atmospheric neutrino fluxes in the context of oscillations of the three known
neutrinos. We aim at a global view which identifies the various possibilities,
rather than attempting the most accurate determination of the parameters of
each scenario. For solar neutrinos we emphasise the importance of performing a
general analysis, independent of any particular solar model and we consider the
possibility that any one of the techniques --- chlorine, gallium or water
Cerenkov --- has a large unknown systematic error, so that its results should
be discarded. The atmospheric neutrino anomaly is studied by paying special
attention to the ratios of upward and downward going nu_e and nu_mu fluxes.
Both anomalies can be described in a minimal scheme where the respective
oscillation frequencies are widely separated or in non-minimal schemes with two
comparable oscillation frequencies. We discuss explicit forms of neutrino mass
matrices in which both atmospheric and solar neutrino fluxes are explained. In
the minimal scheme we identify only two `zeroth order' textures that can result
from unbroken symmetries. Finally we discuss experimental strategies for the
determination of the various oscillation parameters.


title: Eikonalised minijet model analysis of sigma_(gamma gamma)^(inel)

abstract:
  We study the theoretical predictions for the total inelastic $\gamma \gamma$
cross-sections, with an emphasis on the eikonalised minijet model (EMM). In the
context of the EMM, we discuss a new ansatz for the overlap function involving
the photons. We discuss the dependence of the EMM predictions on various input
parameters as well as predictions for \siggg from a simple extension of the
Regge Pomeron Exchange model. We then compare both with the recent LEP data.


abstract:
  We study the structure and perform some explicit calculations for the power
ultraviolet divergences and their renormalization in the Chiral Pertubation
Theory with lattice regularization in 1 and 2 loops.


title:
Next-to-Leading Order QCD corrections to $B\bar B$-mixing and
  $\epsilon_K$ within the MSSM

abstract:
  We present a calculation of the QCD correction factors $\eta_{2B}$ and
$\eta_{2K}$ up to Next-to-Leading Order within the MSSM. We took into account
the region of low $\tan\beta$ for the Higgs- and chargino sector while
neglecting the effect of gluinos and neutralinos.


title: Orbital and field angular momentum in the nucleon

abstract:
  The nucleon spin problem raises experimental and theoretical questions
regarding the contribution of the orbital angular momentum of the quarks to the
total spin of the nucleon. In this article we examine the commutation
relationships of various operators that contribute to the total angular
momentum of the nucleon. We find that the sum of the orbital plus gluon field
angular momentum should satisfy the angular momentum commutators, at least up
to the one-loop level. This requirement on the sum of these operators imposes a
nontrivial restriction on the form of the color electric and magnetic fields.
This is similar to the magnetic monopole/ electric charge system where it is
only the sum of the orbital plus field angular momentum that satisfies the
correct commutation relationships.


title:
Spin-Orbit Force of Instanton-Induced Interaction in Strange and Charmed
  Systems

abstract:
  Effects of the spin orbit-force on hadronic systems with strangeness or charm
are investigated by a valence quark model with the instanton-induced
interaction. By introducing this interaction, the spin-orbit splittings in the
negative-parity hyperons becomes 0.14 -- 0.37 times smaller. The flavor-octet
baryon mass spectrum and the splittings in the charmed baryons become
consistent with the experiments. Though the splitting is also reduced in the
flavor-singlet baryons, it still gives two third of the experimental value. The
reduction comes from the cancellation between the one-gluon exchange and the
instanton-induced interaction, which is channel-specific. In most of the
two-baryon channels, the symmetric and antisymmetric spin-orbit force of the YN
interaction remains strong after introducing this instanton effect. A few
exceptional channels, however, are found where the cancellation affects
strongly and the spin-orbit force becomes small.


title: Effective QCD Interactions of CP-odd Higgs Bosons at Three Loops

abstract:
  In the virtual presence of a heavy quark t, the interactions of a CP-odd
scalar boson A, with mass M_A << 2M_t, with gluons and light quarks can be
described by an effective Lagrangian. We analytically derive the coefficient
functions of the respective physical operators to three loops in quantum
chromodynamics (QCD), adopting the modified minimal-subtraction (MS-bar) scheme
of dimensional regularization. Special attention is paid to the proper
treatment of the gamma_5 matrix and the Levi-Civita epsilon tensor in D
dimensions. In the case of the effective ggA coupling, we find agreement with
an all-order prediction based on a low-energy theorem in connection with the
Adler-Bardeen non-renormalization theorem. This effective Lagrangian allows us
to analytically evaluate the next-to-leading QCD correction to the A -> gg
partial decay width by considering massless diagrams. For M_A = 100GeV, the
resulting correction factor reads 1+(221/12)alpha_s^(5)(M_A)/pi
+165.9(alpha_s^(5)(M_A)/pi)^2 approx 1+0.68+0.23. We compare this result with
predictions based on various scale-optimization methods.


title: Photoproduction of Pion and Kaon Pairs

abstract:
  S-wave photoproduction of pion and kaon pairs on hydrogen is studied. Coupled
channel final state interactions between different pseudoscalar mesons are
included. Effective mass and momentum transfer distributions as well as total
cross sections are calculated. Effective mass distributions in the Born
approximation are structureless but the final state interactions produce peaks
and dips near the energies corresponding to the scalar resonances f0(980) and
f0(1400). Calculations are performed in the effective mass region between the
pion-pion threshold and 1.6 GeV in the range of the momentum transfer squared
up to 2 (GeV/c)^2. The photon energy dependence of the total cross sections is
studied between 2 and 15 GeV. Valuable information on the f0(980) resonance
structure can be extracted from data.
  These calculations are closely related to the experimental program of the
CEBAF accelerator in USA.


title: QCD phases at high density and instantons

abstract:
  The talk is an introduction into diquark condensation phenomena which occur
in QCD at high energy density. They are driven by instantons and
instanton-antiinstanton pairs (or ``molecules''), which generate attraction in
some qq channels. A number of phases is possible, with or without restoration
of chiral symmetry: the work is not finished and we do not yet know which take
place in real QCD. We also emphasize that specific diquark correlations play a
significant role in baryon structure, in particular making that of a nucleon
very different of a $\Delta$ (or other member of a decuplet). This ``small
$N_c$'' scenario based on comparison to QCD with two colors is contrasted with
the ``large $N_c$'' one.


title: Quantum SUSY signatures in low and high energy processes

abstract:
  In the search for phenomenological evidence of supersymmetry through the
indirect method of quantum signatures, it is useful to seek correlations of the
non-standard quantum effects in low and high energy proceses, such as those
involving on one hand the properties of the B-mesons and on the other hand the
physics of the top quark and of the Higgs bosons. There are regions of the MSSM
parameter space where the potential quantum SUSY signatures in the two energy
regimes are strongly interwoven and therefore the eventual detection of these
correlated quantum effects would strongly point towards the existence of
underlying supersymmetric dynamics.


title: Pauli-Villars Regularization in a Discrete Light-Cone Model

abstract:
  Pauli-Villars regularization is successfully applied to nonperturbative
calculations in a (3+1)-dimensional light-cone model. Numerical results
obtained with discretized light-cone quantization compare favorably with the
analytic solution.


title: A Chiral Supersymmetric Standard Model

abstract:
  We propose a supersymmetric extension of the Standard Model with an extra
U(1) gauge symmetry, so that all supersymmetric mass terms, including the
$\mu$-term, are forbidden by the gauge symmetries. Supersymmetry is broken
dynamically which results in U(1) breaking and generation of realistic $\mu$
term and soft breaking masses. The additional fields required to cancel the
U(1) anomalies are identified with the messengers of supersymmetry breaking.
The gaugino masses arise as in the usual gauge mediated scenario, while squarks
and sleptons receive their masses from both the U(1) $D$-term and the two-loop
gauge mediation contributions. The scale of supersymmetry breaking in this
model can be below $10^6$ GeV, yielding collider signatures with decays to
goldstinos inside the detector.


title: Jet Quenching and Cronin Enhancement in A+A at s^1/2=20 vs 200 AGeV

abstract:
  The sensitivity of semi-hard (p_\perp < 10 GeV) hadron production to parton
energy loss in high energy nuclear collisions is studied via the HIJING1.35
model. We test the model on recent WA98 data on 160 AGeV Pb+Pb -> pi^0 up to 4
GeV/c and while these data are reproduced, the results depends sensitively on
the model of the Cronin effect. At (RHIC) collider energies (s^1/2 > 200 AGeV),
on the other hand, semi-hard hadron production becomes insensitive to the above
model and is thus expected to be a cleaner probe of jet quenching signature
associated with non-Abelian radiative energy loss.


title:
The length distribution of vortex strings in U(1) equilibrium scalar
  field theory

abstract:
  We characterize the statistical length distribution of vortex strings by
studying the non-perturbative thermodynamics of scalar U(1) field theory in 3D.
All parameters characterizing the length distributions exhibit critical
behavior at $T_c$ and we measure their associated critical exponents. Moreover
we show that vortex strings are generally self-seeking at finite temperature
and that there exists a natural separation between long strings and small loops
based on their spatial correlation behavior.


title: Small x behaviour of parton distributions with soft initial conditions

abstract:
  We present an analytical parametrization of the QCD description of the small
x behaviour of parton distribution functions in the leading twist approximation
of the Wilson operator product expansion, in the case of soft initial
conditions. The results are in very good agreement with deep inelastic
scattering experimental data from HERA.


title: A Simple Born-Form Approximation for e^+ e^- to W^+W^- at One Loop

abstract:
  A simple Born-form approximation at the one-loop level for e^+e^- to W^+ W^-
at high energies is given in analytic form. The different contributions to the
three invariant one-loop amplitudes, S_I^{(-)}(s,t) and S_Q^{(\pm)}(s,t),
determining the Born-form helicity amplitudes are thoroughly investigated
analytically and numerically. At energies above 500 GeV, the accuracy of the
simple Born-form approximation for the differential production cross section is
better than 1% for almost all W^+W^- production angles, independently of
whether the W^+W^- polarization is summed over, or whether a longitudinal or a
transverse polarization is selected for both the W^+ and the W^-.


title: Polarized Parton Densities in the Nucleon

abstract:
  We present a critical assessment of what can be learnt from the present data
on inclusive polarized DIS. We examine critically some of the simplifying
assumptions made in recent analyses and study in detail the question of the
determination of the gluon, strange sea and valence quark polarized densities.
  We have also carried out a new NLO QCD analysis of the world data. We find an
excellent fit to the data and present our results for the polarized parton
densities.


title: Studying thermodynamics in heavy ion collisions

abstract:
  We discuss the possibility to measure entropy of the system created in heavy
ion collisions using the Ma coincidence method.


title: Atmospheric Neutrino Anomaly and Supersymmetric Inflation

abstract:
  A detailed investigation of hybrid inflation and the subsequent reheating
process is performed within a mu problem solving supersymmetric model based on
a left-right symmetric gauge group. The process of baryogenesis via
leptogenesis is especially studied. For mu and tau neutrino masses consistent
with the small angle MSW resolution of the solar neutrino problem and the
recent results of the SuperKamiokande experiment, we show that maximal mu-tau
neutrino mixing can be achieved. The required value of the relevant coupling
constant is, however, quite small (of the order 10^{-6}).


title: A Model Independent Analysis of the Rare B Decay B -> X_s l^+ l^-

abstract:
  The most general model-independent analysis of the rare $B$ decay, $\Bsll$,
is presented. There are ten independent local four-Fermi interactions which may
contribute to this process. The branching ratio, the forward-backward
asymmetry, and the double differential rate are written as functions of the
Wilson coefficients of the ten operators. We also study the correlation between
the branching ratio and the forward-backward asymmetry by changing each
coefficient. This procedure tells us which types of operator contribute 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 the deviation from
the Standard Model is found.


title:
Electromagnetic and weak current operators for interacting systems
  within the front-form dynamics

abstract:
  Electromagnetic and weak current operators for interacting systems should
properly commute with the Poincar\'e generators and satisfy Hermiticity. The
electromagnetic current should also satisfy ${\cal P}$ and ${\cal T}$
covariance and continuity equation. We show that in front-form dynamics the
current can be constructed from auxiliary operators, defined in a Breit frame
where initial and final three-momenta of the system are directed along the
  $z$ axis. Poincar\'e covariance constraints reduce for auxiliary operators to
the ones imposed only by kinematical rotations around the $z$ axis; while
Hermiticity requires a suitable behaviour of the auxiliary operators under
rotations by $\pi$ around the $x$ or $y$ axes. Applications to deep inelastic
structure functions and electromagnetic form factors are discussed. Elastic and
transition form factors can be extracted without any ambiguity and in the
elastic case the continuity equation is automatically satisfied, once
Poincar\'e, ${\cal P}$ and ${\cal T}$ covariance, together with Hermiticity,
are imposed.


title:
The exclusive \bar{B} --> \pi e^+ e^- and \bar{B} --> \rho e^+ e^-
  decays in the two Higgs doublet model with flavor changing neutral currents

abstract:
  We calculate the leading logarithmic QCD corrections to the matrix element of
the decay b --> d e^+ e^- in the two Higgs doublet model with tree level flavor
changing currents (model III). We continue studying the differential branching
ratio and the CP violating asymmetry for the exclusive decays B --> \pi e^+ e^-
and B --> \rho e^+ e^- and analysing the dependencies of these quantities on
the selected model III parameters, \xi^{U,D}, including the leading logarithmic
QCD corrections. Further, we present the forward-backward asymmetry of
dileptons for the decay B --> \rho e^+ e^- and discuss the dependencies to the
model III parameters. We observe that there is a possibility to enhance the
branching ratios and suppress the CP violating effects for both decays in the
framework of the model III. Therefore, the measurements of these quantities
will be an efficient tool to search the new physics beyond the SM.


title: Multipion symmetrization effects on the source distribution

abstract:
  Any-order pion interferometry formulas for fixed pion multiplicity events and
for mixed events are given. Multipion Bose-Einstein correlation effects on the
two-pion interferometry and source distribution are studied. It is shown that
generalized pion interferometry formula should depneds on pion multiplicity
distribution. Pion condensate is also discussed in the paper.


title:
Charmonium Suppression in Lead-Lead Collisions: Is There a Break in the
  $J/\psi$ Cross-Section?

abstract:
  In the framework of a model based on nuclear absorption plus comover
interaction, we compute the $E_{T}$ distribution of the $J/\psi$ in $PbPb$
collisions at SPS and compare it with available NA50 data. Our analysis
suggests that the existence of new physics (deconfinement phase transition) in
the region $E_{T} \lsim 100$ GeV is unlikely and that signals of new physics
should rather be searched in the region $E_T \gsim 100$ GeV. The $E_{T}$
dependence of the $J/\psi$ transverse momentum has been computed. At large
$E_T$ it turns out to be much flatter in the comover approach than in a phase
transition framework. Estimates of the $J/\psi$ suppression at RHIC and LHC
energies are also given.


title:
Two-loop large Higgs mass contribution to vector boson anomalous quartic
  couplings

abstract:
  The calculation of the two-loop corrections to the electroweak gauge boson
quartic couplings, growing quadratically with the Higgs boson mass, is
reviewed. The potential of the CERN Large Hadron Collider and e+e- linear
collider to study such anomalous interactions is discussed.


title:
Effect of quark-jet energy loss on direct photons in ultrarelativistic
  heavy-ion collisions

abstract:
  We discuss the transverse momentum distribution of thermal and prompt photons
in ultrarelativistic heavy ion collisions. The prompt photons are mostly
produced by fragmentation of quark jets (bremsstrahlung). If these quark jets
suffer a large energy loss in heavy-ion reactions, prompt photons are
significantly suppressed. Thermal electromagnetic radiation from the
quark-gluon plasma and the hadron gas might then dominate the intermediate
k_T-range. In central Au+Au collisions at \sqrt{s}=200A GeV, and in the range 2
GeV < k_T < 4 GeV, the inverse slope of the thermal radiation is 360-460 MeV,
while that of the QCD photons is 500-1000 MeV. This large difference might
allow to disentangle the various sources of direct photons experimentally. At
\sqrt{s}=5.5A TeV, nuclear shadowing and quark-jet quenching suppresses the
QCD-photons strongly for k_T<5 GeV. Thermal radiation dominates in this
k_T-region.


title: Solitons in a chiral quark model with non-local interactions

abstract:
  Hedgehog solitons are found in a chiral quark model with non-local
interactions. The solitons are stable without the chiral-circle constraint for
the meson fields, as was assumed in previous Nambu-Jona--Lasinio model with
local interactions.


title:
The Reach of CERN LEP2 and Fermilab Tevatron Upgrades for Higgs Bosons
  in Supersymmetric Models

abstract:
  Luminosity upgrades of the Fermilab Tevatron pbar-p collider have been shown
to allow experimental detection of a Standard Model (SM) Higgs boson up to
$m_{H_{SM}}\sim 120$ GeV via $WH_{SM} \to \ell\nu b\bar{b}$ events. This limit
nearly saturates the parameter space for many models of weak scale
supersymmetry (SUSY) with a minimal particle content. It is therefore
interesting to examine the SUSY Higgs reach of future Tevatron experiments.
Contours are presented of Higgs boson reach for CERN LEP2 and Tevatron
luminosity upgrades for three models of weak scale SUSY: the Minimal
Supersymmetric Standard Model (MSSM), the minimal Supergravity model (mSUGRA)
and a simple Gauge Mediated SUSY Breaking Model (GMSB). In each case we find a
substantial gain in reach at the Tevatron with integrated luminosity increasing
from 10 fb^{-1} to 25-30 fb^{-1}. With the larger integrated luminosity, a
Higgs search at the Tevatron should be able to probe essentially the entire
parameter space of these models. While a discovery would be very exciting, a
negative result would severely constrain our ideas about how weak scale
supersymmetry is realized.


title: On the Determination of Small x Shadowing Corrections at HERA

abstract:
  The recent $F_2$ data can be described using the DGLAP evolution equations
with an appropriate choice of input distributions and the choice of the
starting scale for the $Q^2$ evolution. We demonstrate in this paper that we
cannot conclude that there are no significant shadowing corrections at HERA
kinematic region using $F_2$ data only. In this paper we calculate the
shadowing corrections to the longitudinal structure function $F_L(x,Q^2)$ and
to the charm component of the proton structure function $F_2^c(x,Q^2)$ at HERA
kinematic region using an eikonal approach. We demonstrate that the shadowing
corrections to these observables are very large and that the charm production
is strongly modified at small-$x$. Our results agree with the recent few H1
data.


title: Neutrino Interactions at Ultrahigh Energies

abstract:
  We report new calculations of the cross sections for deeply inelastic
neutrino-nucleon scattering at neutrino energies between $10^{9}\ev$ and
$10^{21}\ev$. We compare with results in the literature and assess the
reliability of our predictions. For completeness, we briefly review the cross
sections for neutrino interactions with atomic electrons, emphasizing the role
of the $W$-boson resonance in $\bar{\nu}_{e}e$ interactions for neutrino
energies in the neighborhood of $6.3\pev$. Adopting model predictions for
extraterrestrial neutrino fluxes from active galactic nuclei, gamma-ray
bursters, and the collapse of topological defects, we estimate event rates in
large-volume water \v{C}erenkov detectors and large-area ground arrays.


title:
Cosmological Moduli Problem in a Supersymmetric Model with Direct Gauge
  Mediation

abstract:
  Recently, an interesting class of the direct gauge mediation supersymmetry
(SUSY) breaking models are proposed, in which the minimum of the potential of
the SUSY breaking field is determined by the inverted hierarchy mechanism. We
consider their cosmological implications. In this class of models, SUSY
breaking field has a very flat potential, which may have a cosmological
importance. Assuming the initial amplitude of the SUSY breaking field to be of
the order of the Planck scale, it can be a source of a large entropy
production. A special attention is paid to the cosmological moduli problem, and
we will see the cosmological mass density of the moduli field can be
significantly reduced.


title: Note on the field theory of neutrino mixing

abstract:
  The problem of the diagonalization of the flavor-neutrino propagator mat rix
is investigated in the theory with flavor-mixing mass terms in Lagrangian. For
this purpose we examine one-pole structures of flavor-neutrino propa gators,
leading to physical neutrino masses, and discuss the relation of the pro
pagator diagonalizaion to the diagonalizaion of the mass matrix in Lagrangian.
In connection with the paper by Blasone et al., it is pointed out that t here
is no compelling reason for fixing the mass parameters, althought this fixi ng
is necessary in order to construct the flavor Hilbert space.


title:
Reconciling Super-Kamiokande, LSND, and Homestake neutrino-oscillation
  data

abstract:
  The L/E-flatness of the e-like events observed in the recent
atmospheric-neutrino data from Super-Kamiokande (SuperK) is interpreted to
reflect a new symmetry of the neutrino-oscillation mixing matrix. From that we
obtain an analytical set of constraints yielding a class of mixing matrices of
the property to simultaneously fit both the SuperK and the LSND data. The
resulting mass squared difference relevant for the LSND experiment is found as
0.3 eV^2. The discussed symmetry, e.g., carries the nature that expectation
values of masses for \nu_\mu and \nu_\tau are identical. These considerations
are purely data dictated. A different framework is then applied to the solar
neutrino problem. It is argued that a single sterile neutrino is an unlikely
candidate to accommodate the data from the four solar neutrino experiments. A
scenario is discussed which violates CPT symmetry, and favors the \nu_e -
\bar\nu_e system to belong to the `self'-`anti-self' charge conjugate construct
in the (1/2,0)+(0,1/2) representation space, where the needed helicity flipping
amplitudes are preferred, rather than the usual Dirac, or Majorana, constructs.
In the presented framework the emerging SuperK data on solar neutrino flux is
reconciled with the Homestake, GALLEX, and SAGE experiments. This happens
because the former detects not only the solar \nu_e but also, at a lower cross
section, the oscillated solar \bar\nu_e; while the latter are sensitive only to
the oscillation-diminished solar \nu_e flux. A direct observation of solar
\bar\nu_e by SNO will confirm our scenario. Finally, we consider the
possibility for flavor-dependent gravitational couplings of neutrinos as
emerging out of the noncommutativity of the quantum operators associated with
the measurements of energy and flavor.


title: Phenomenological description of the gamma* p cross section at low Q2

abstract:
  Low Q2 photon-proton cross sections are analysed using a simple,
QCD-motivated parametrisation $\sigma_{\gamma^\star p}\propto 1/(Q^2+Q_0^2)$,
which gives a good description of the data. The Q2 dependence of the gamma* p
cross section is discussed in terms of the partonic transverse momenta of the
hadronic state the photon fluctuates into.


title: MSSM Dark Matter Constraints and Decaying B-balls

abstract:
  In the MSSM, LSP dark matter could arise from the decay of B-balls rather
than from thermal relics, with a quite different dependence on the MSSM
parameters and a natural correlation with the baryon asymmetry. We discuss the
constraints imposed on the properties of B-balls and the MSSM spectrum by
experimental constraints and show that B-balls cannot form from an Affleck-Dine
condensate with 100% efficiency in the absence of LSP annihilations after they
decay. For likely formation efficiencies the LSP and slepton masses are
typically constrained to be light. The effects of LSP annihilations after the
B-balls decay are discussed; for sufficiently small decay temperatures
annihilations will play no role, opening up the possibility of experimentally
testing the scenario.


title: More Insight into Heavy Quark Masses from QCD

abstract:
  Using the non-relativistic version of Borel sum rules, combined to the very
accurate experimental information on the Charmonium and Upsilon spectra, we
rigorously investigate the Euclidean mass of the Charm and Bottom quark. Our
analysis is performed with an improved expansion of the heavy current
correlator in the infinite heavy quark mass limit. The optimal results, which
take into account the most recent world average values of the strong coupling
constant, as well as a conservative range of the gluon condensate, are:
m_c^Eucl=1.20+-0.034 GeV and m_b^Eucl=4.18+-0.037 GeV. Their conversions to the
corresponding pole mass and running mass give respectively: M_c=1.49+-0.08 GeV,
M_b=4.65+-0.06 GeV and m_c(m_c)=1.21+-0.08 GeV, m_b(m_b)=4.20+-0.06 GeV in good
agreement with the most recent direct estimates.


title: Direct emission of light mesons from quark-gluon plasma surface

abstract:
  On the basis of hydrodynamic model of evolution of heavy ion collision we
consider emission of $\pi,K,\eta,\rho,\omega,K^*$ mesons directly from the
surface of quark-gluon plasma, with accounting of their absorption by
surrounding plasma hadronic gas. We evaluate upper and lower limits on yields
of these direct mesons in Pb+Pb collision at 158 AGeV (SpS) and 3150+3150 AGeV
(LHC), and find, that even in the case of the lowest yield, direct $\eta$ and
heavier mesons dominate at LHC energy at soft $p_t$ ($p_t\le 0.5 GeV/c$). This
enhancement of the low $p_t$ meson production can be considered as a
quark-gluon plasma signature.


title: Free energy of bubbles and droplets in the quark-hadron phase transition

abstract:
  Using the MIT bag model, we calculate the free energy of droplets of
quark-gluon plasma in a bulk hadronic medium, and of hadronic bubbles in a bulk
quark-gluon plasma, under the assumption of vanishing chemical potentials. We
investigate the validity of the multiple reflection expansion approximation,
and we advise a novel procedure for calculating finite-size corrections to the
free energy of hadronic bubbles in a bulk quark-gluon plasma. While our results
agree largely with earlier calculations, we show that the usual multiple
reflection expansion should be used with caution, and we propose a modification
of the multiple reflection expansion, which makes this approximation agree
nicely with direct numerical calculations. The results should be of relevance
in connection with the cosmological quark-hadron transition as well as for
ultrarelativistic heavy ion collisions.


title: Pre-LHC SUSY Searches: an Overview

abstract:
  We discuss the prospects for searches of low-energy supersymmetry in the time
interval separating us from the advent of LHC. In this period of time
"indirect" searches may play a very relevant role. We refer to manifestations
of supersymmetry in flavour changing neutral current and CP violating phenomena
and to signals of the lightest supersymmetric particle in searches of dark
matter. In the first part of the talk we critically review the status of the
minimal supersymmetric model to discuss the chances that direct and indirect
supersymmetric searches may have before the LHC start. In the second part we
point out what we consider to be the most promising grounds where departures
from the standard model prediction may signal the presence of new physics,
possibly of supersymmetric nature. We argue that the often invoked
complementarity of direct and indirect searches of low-energy supersymmetry is
becoming even more true in the pre-LHC era.


title: Nucleon Structure Functions and Light-Front Dynamics

abstract:
  We present a quark-parton model to describe polarized and unpolarized nucleon
structure functions. The twist-two matrix elements for the QCD evolution
analysis of lepton-hadron scattering are calculated within a light-front
covariant quark model. The relativistic effects in the three-body wave function
are discussed for both the polarized and unpolarized cases. Predictions are
given for the polarized gluon distributions as will be seen in future
experiments.


title: A No-Lose Theorem for Higgs Searches at a Future Linear Collider

abstract:
  Assuming perturbativity up to a high energy scale $\sim 10^{16}$ GeV, we
demonstrate that a future $e^+e^-$ linear collider operating at $\sqrt{s} =$
500 GeV with $\int{\cal L}=$ 500 fb$^{-1}$ per year (such as the recently
proposed TESLA facility) will detect a Higgs boson signal regardless of the
complexity of the Higgs sector and of how the Higgs bosons decay.


title: A set of sum rules for anomalous gauge boson couplings

abstract:
  The dependence of the differential cross-section for on-shell W-pair
production on the anomalous trilinear gauge couplings invariant under C and P
is examined. It is shown that the contributions of the anomalous magnetic
moments of the W boson due to the photon and the Z can be individually
projected out by means of two appropriately constructed polynomials. The
remaining four anomalous couplings are shown to satisfy a set of
model-independent sum rules. Specific models which predict special relations
among the anomalous couplings are then studied; in particular, the composite
model of Brodsky and Hiller, and the linear and non-linear effective Lagrangian
approaches. The relations predicted by these models, when combined with the
aforementioned sum rules, give rise to definite predictions, particular to each
model. These predictions can be used, at least in principle, in order to
exclude or constrain such models.


title: Flavour-Changing Neutral Currents in the Dualized Standard Model

abstract:
  The Dualized Standard Model which gives explanations for both fermion
generations and Higgs fields has already been used to calculate fermion mass
and mixing parameters with success. In this paper, we extend its application to
low energy FCNC effects deriving bounds for various processes in terms of one
single mass scale. Using then experimental information from K_L - K_S mass
difference and air showers beyond the GZK cut-off, these bounds are converted
into rough, order-of-magnitude predictions. In particular, the estimates for
the decay K_L \to e^\pm \mu^\mp and for the mass difference between the neutral
D-mesons seem accessible to experiment in the near future.


title:
Particle Physics Models of Inflation and the Cosmological Density
  Perturbation

abstract:
  This is a review of particle-theory models of inflation, and of their
predictions for the primordial density perturbation that is thought to be the
origin of structure in the Universe. It contains mini-reviews of the relevant
observational cosmology, of elementary field theory and of supersymmetry, that
may be of interest in their own right. The spectral index $n(k)$, specifying
the scale-dependence of the spectrum of the curvature perturbation, will be a
powerful discriminator between models, when it is measured by Planck with
accuracy $\Delta n\sim 0.01$. The usual formula for $n$ is derived, as well as
its less familiar extension to the case of a multi-component inflaton; in both
cases the key ingredient is the separate evolution of causally disconnected
regions of the Universe. Primordial gravitational waves will be an even more
powerful discriminator if they are observed, since most models of inflation
predict that they are completely negligible. We treat in detail the new wave of
models, which are firmly rooted in modern particle theory and have
supersymmetry as a crucial ingredient. The review is addressed to both
astrophysicists and particle physicists, and each section is fairly homogeneous
regarding the assumed background knowledge.


title: Six Fermion Production at LC

abstract:
  We review some features and results of the calculations performed with the
program SIXPHACT for six fermion final states at Linear Collider


title: Large CP Violation in $B\to K^{(*)} X$ Decays

abstract:
  We consider the possibility of observing CP violation in quasi-inclusive
decays of the type $B^-\to K^- X$, $B^-\to K^{*-} X$,
  $\bar B^0\to K^- X$ and $\bar B^0\to K^{*-} X$, where $X$ does not contain
strange quarks. We present estimates of rates and asymmetries for these decays
in the Standard Model and comment on the experimental feasibility of observing
CP violation in these decays at future $B$ factories. We find the rate
asymmetries can be quite sizeable.


title: The Phenomenology of SUSY models with a Gluino LSP

abstract:
  In this paper we study the experimental consequences of a theory which
naturally has a heavy, stable (or almost stable) gluino. We define the boundary
conditions at a messenger scale $M \sim 10^{14}$ GeV which lead to this
alternative phenomenologically acceptable version of the minimal supersymmetric
standard model.
  In this theory, either the gluino or the gravitino is the lightest
supersymmetric particle [LSP]. If the gravitino is the LSP, then the gluino is
the next-to-LSP with a lifetime on the order of 100 years. In either case, the
gluino is (for all practical purposes) a stable particle with respect to
experiments at high energy accelerators. Thus the standard missing energy
signature for SUSY fails. A stable gluino forms a color singlet hadron, the
lightest of which is assumed to be an isoscalar gluino-gluon bound state
($R_0$). The $R_0$ has strong interactions and will interact in a hadronic
calorimeter; depositing some fraction of its kinetic energy. Finally, in the
case the gravitino is the LSP, bounds from searches for stable heavy isotopes
of hydrogen or oxygen do not apply to the metastable $R_0$.


title: High Energy Neutrinos from Astrophysical Sources: An Upper Bound

abstract:
  We show that cosmic-ray observations set a model-independent upper bound to
the flux of high-energy, > 10^14 eV, neutrinos produced by photo-meson (or p-p)
interactions in sources of size not much larger than the proton photo-meson (or
pp) mean-free-path. The bound applies, in particular, to neutrino production by
either AGN jets or GRBs. This upper limit is two orders of magnitude below the
flux predicted in some popular AGN jet models, but is consistent with our
predictions from GRB models. We discuss the implications of these results for
future km^2 high-energy neutrino detectors.


title: Vacuum Neutrino Oscillations of Solar Neutrinos and Lepton Mass Matrices

abstract:
  We consider the case that the solar neutrino deficit is due to the vacuum
oscillation. The lepton mass matrices with nearly bi-maximal mixings are needed
in order to explain both solar and atmospheric neutrino deficit. A texture with
the symmetry of flavour democracy or $S_3$ has been investigated by taking
account of the symmetry breaking terms of the charged lepton mass matrix. It is
found that predicted mixings can be considerably changed from the neutrino
mixings $\sin^2 2\th_\odot\simeq 1$ and
  $\sin^2 2\th_{\rm atm}\simeq 8/9$ at the symmetric limit. The correlation
between $|U_{e3}|$ and $|U_{e1}U_{e2}^*|$ is also presented. The test of the
model is discussed by focusing on the three flavor analyses in the solar
neutrinos, atmospheric neutrinos and long baseline experiments.


title:
Systematic technique for computing infrared properties of 2+1- and 3+1-
  dimensional Yang-Mills theory

abstract:
  New collective coordinates, related to the field at the `center' of the
monopoles, are proposed. A systematic computation of the infrared properties of
2+1- and 3+1- dimensional Yang-Mills theory is now possible and is related to
solutions of classical equations with constraints at isolated points. For
2+1-dimensional Yang-Mills theory, monopoles of a specific size proportional to
$g^{-2}$ dominate and a semiclassical technique is applicable. For
3+1-dimensional Yang-Mills theory, the formalism incorporates a monopole
condensate naturally, and is therefore a correct starting point for
computations of confinement properties. The method also provides a precise way
of going beyond the dilute gas approximation for instantons in 3+1-dimensions.
Another algorithm, which uses only the quadratic form of the action and
corrections via renormalized perturbation theory, is proposed as a viable
scheme of computation for all length scales.


title: Q-balls in the MSSM

abstract:
  In the MSSM with gravity mediated supersymmetry breaking, there may exist
unstable but long-lived solitons carrying large baryonic charge, or B-balls.
These decay well afterthe electroweak phase transition, giving rise to B-ball
baryogenesis. Being made of squarks, B-ball decays produce also LSPs and hence
can be the source for all cold dark matter.


title:
Chiral Symmetry Breaking without Bilinear Condensates, Unbroken Axial
  Z_N Symmetry, and Exact QCD Inequalities

abstract:
  An alternative pattern of the chiral symmetry breaking, suggested recently by
Stern, is investigated. It could be self-consistent provided that the chiral
$SU(N_f) \times SU(N_f)$ symmetry is broken spontaneously down to $SU(N_f)
\times Z_{N_f}$ rather than to $SU(N_f)_V$. The discrete axial $Z_{N_f}$ then
would play a custodial role preventing the quark bilinears from condensation.
It is shown that this pattern of the chiral symmetry breaking is ruled out in
QCD by exact inequalities. It is not ruled out, however, in other gauge
theories with scalar quarks and/or Yukawa couplings.


title: Exclusive $J/\psi$ photoproduction and gluon polarization

abstract:
  In exclusive $J/\psi$ production by polarized photons incident on polarized
protons, a finite polarization asymmetry arises because of $c\bar c$
Fermi-motion and binding-energy effects. The asymmetry depends on the polarized
nonforward gluon distribution of the proton and thus gives information on gluon
polarization in the proton. The analyzing power, however, is rather small.


title: On the Calculation of QED Amplitudes in a Constant Field

abstract:
  It is explained how first-quantized worldline path integrals can be used as
an efficient alternative to Feynman diagrams in the calculation of QED
amplitudes and effective actions. The examples include the one-loop photon
splitting amplitude, the two-loop Euler-Heisenberg Lagrangian, and the one-loop
axial vacuum polarization tensor in a general constant electromagnetic field.