title:
Event-by-Event Fluctuations in Heavy Ion Collisions and the QCD Critical
  Point

abstract:
  The event-by-event fluctuations of suitably chosen observables in heavy ion
collisions at SPS, RHIC and LHC can tell us about the thermodynamic properties
of the hadronic system at freeze-out. By studying these fluctuations as a
function of varying control parameters, it is possible to learn much about the
phase diagram of QCD. As a timely example, we stress the methods by which
present experiments at the CERN SPS can locate the second-order critical
endpoint of the first-order transition between quark-gluon plasma and hadron
matter. Those event-by-event signatures which are characteristic of freeze-out
in the vicinity of the critical point will exhibit nonmonotonic dependence on
control parameters. We focus on observables constructed from the multiplicity
and transverse momenta of charged pions. We first consider how the
event-by-event fluctuations of such observables are affected by Bose-Einstein
correlations, by resonances which decay after freeze-out and by fluctuations in
the transverse flow velocity. We compare our thermodynamic predictions for such
noncritical event-by-event fluctuations with NA49 data, finding broad
agreement. We then focus on effects due to thermal contact between the observed
pions and a heat bath with a given (possibly singular) specific heat, and due
to the direct coupling between the critical fluctuations of the sigma field and
the observed pions. We also discuss the effect of the pions produced in the
decay of sigma particles just above threshold after freeze-out on the inclusive
pion spectrum and on multiplicity fluctuations. We estimate the size of these
nonmonotonic effects which appear near the critical point, including
restrictions imposed by finite size and finite time, and conclude that they
should be easily observable.


title: Colour-straight four-quark operators and liftemes of beautiful hadrons

abstract:
  Using the relation between the harmonic oscillator wave function and the
light quark scattering form factor, the expectation values of colour-straight
four-quark operators are evaluated and found to be directly proportional to the
cubic power of the oscillator strength. It is predicted that the ratio
\tau(\Lambda_b)/\tau(B) \approx 0.79(0.84) due to the factorizable
(nonfactorisable) piece, against the experimental 0.79 \pm 0.06.
Notwithstanding the numerical prediction, the present study shows that the
four-quark operators play a role as far the lifetimes of b-flavoured hadrons
are concerned.


title: Direct Signals of Low Scale Gravity at $e^+ e^-$ Colliders

abstract:
  Gravity can become strong at the TeV scale in the theory of extra dimensions.
An effective Lagrangian can be used to describe the gravitational interactions
below a cut-off scale. In this work, we study the associated production of the
gravitons with a $Z$ boson or a photon at $e^+ e^-$ colliders of energies of
LEPII to the Next Linear Colliders (NLC) ($\sqrt{s}=0.25-1.5$ TeV) and
calculate the sensitivity to the new interactions. We also obtain the limit on
the cut-off scale using the present data from LEPII.


title: Jets and fragmentation

abstract:
  I review the status of next-to-leading-order calculations for hadronic final
states in deeply-inelastic lepton--nucleon scattering. In more detail, I focus
on calculations of (2+1)-jet-type cross sections, describe recent progress in
extending the perturbative description into the transition region between
deeply inelastic scattering and photoproduction, and study the validity of the
fragmentation function picture for one-particle-inclusive cross sections at
small Q^2 and small x_p.


title: A Unified Treatment of High Energy Interactions

abstract:
  It is well known that high energy interactions as different as
electron-positron annihilation, deep inelastic lepton-nucleon scattering,
proton-proton interactions, and nucleus-nucleus collisions have many features
in common. Based upon this observation, we construct a model for all these
interactions, which relies on the fundamental hypothesis that the behavior of
high energy interactions is universal.


title: New phases of QCD, the tricritical point, and RHIC as a ``nutcracker''

abstract:
  Because too many interesting things are going on now, I have tried to squeeze
three different subjects into one talk. The first is a brief summary of the
color super-conductivity. During the last year we learned that
instanton-induced forces can not only break chiral symmetry in the QCD vacuum,
but also create correlated scalar diquarks and form new phases,some similar to
the Higgs phase of the Standard model. The second issue I discuss is the
remnant of the so called $tricritical$ point, which in QCD with physical masses
is the endpoint of the first order transition. I will argue that exchange of
sigmas (which are massless at this point even with quark masses included)
create interesting event-by-event fluctuations, which can be used to locate it.
Finally I describe first results on $flow$ calculations for non-central
collisions at RHIC. It was found that it is extremely sensitive to Equation of
State (EOS). Furthermore, the unusual ``nutcracker'' picture emerges for
lattice-motivated EOS, which is formation of two $shells$ which are physically
separated $before$ the freeze-out.


title: Effects of Kaluza-Klein Excitations on g_{\mu}-2

abstract:
  An analysis of the effects associated with the Kaluza-Klein excitations of
the photon and of the W and Z bosons on g_{\mu}-2 for d number of extra
dimensions with large radius compactifications is given. The Kaluza-Klein
effects on g_{\mu}-2 are found to be very sensitive to the number of extra
dimensions. For models where the quark-lepton generations live on the 4D wall,
it is shown that when the constraints from the Kaluza-Klein corrections to the
Fermi constant are included, the effects of the Kaluza-Klein excitations to
g_{\mu}-2 become too small to be observable. A model which evades Kaluza-Klein
corrections to the muon decay \mu\to e\bar\nu_e\nu_{\mu} without suppression of
their effects on g_{\mu}-2 is discussed.


title: Testing flavor-changing neutral currents in the rare decays t->cViVj

abstract:
  We discuss the Flavor-Changing Neutral Current (FCNC) decays of the top quark
t -> c Vi Vj (Vi=gamma, Z, g) in the framework of the Standard Model (SM) and
in a two-higgs doublet model (2HDM) with tree-level FCNC couplings. While in
the SM the expected branching ratios are extremelly small, in the 2HDM they may
be sizable, of order 10^(-5) - 10^(-5), and thus accesible at the CERN LHC. We
conclude with the interesting observation that the FCNC decay modes may not be
equally suppressed as their corresponding decays t ->c Vi in this 2HDM.


title: Gauge dilution and leptogenesis

abstract:
  In this paper, we examine how gauge interactions can dilute the lepton
asymmetry in lepton induced baryogenesis. Constraints imposed on Majorana
masses keep this dilution at an acceptable level.


title: Higgs boson production in e^+e^- and e^-e^- collisions

abstract:
  When Higgs boson candidates will be found at future colliders, it becomes
imperative to determine their properties, beyond the mass, production cross
section and decay rates. Other crucial properties are those related to the
behaviour under CP transformations, and the self-couplings. This paper
addresses the question of measurability of some of the trilinear couplings of
MSSM neutral Higgs bosons at a high-energy e^+e^- collider, and the
possibilities of exploring the Higgs boson CP properties at e^+e^- and e^-e^-
colliders.


title: Remarks on parametric resonance of neutrino oscillations in the earth

abstract:
  Neutrino oscillations in matter can exhibit a specific resonance enhancement
-- parametric resonance, which is different from the MSW resonance. Recently it
has been shown that the oscillations of atmospheric and solar neutrinos inside
the earth can undergo parametric enhancement when neutrino trajectories cross
the core of the earth. In this paper we continue the study of the parametric
resonance of neutrino oscillations in the earth. The following issues are
discussed: stability of the resonance with respect to the variations of the
zenith angle of the neutrino source; higher-order resonances; prospects of the
experimental observation of the parametric resonance of neutrino oscillations.
We also comment on a recent controversy regarding the physical nature of the
resonance enhancement of the oscillations of the core crossing neutrinos in the
earth.


title:
Enhancing the Seasonal Variation Effect in the Case of the Vacuum
  Oscillation Solution of the Solar Neutrino Problem

abstract:
  We study in detail the threshold energy dependence of the seasonal variation
effect in the energy integrated solar neutrino signal of the Super-Kamiokande
detector in the case of the $\nu_{e}\leftrightarrow \nu_{\mu,\tau}$ vacuum
oscillation (VO) solution of the solar neutrino problem. We show, in
particular, that for the values of $\Delta m^2$ and $\sin^22\theta$ from the VO
solution region, the predicted time and threshold e^- energy ($T_{e,Th}$)
dependence of the event rate factorize to a high degree of accuracy. As a
consequence, the VO generated seasonal variation asymmetry is given by the
product of an time-independent function of $T_{e,Th}$ and the standard
geometrical asymmetry. For any given $\Delta m^2$ and $\sin^22\theta$ from the
VO solution region there exists at least one value of $T_{e,Th}$ from the
interval (5 - 11) MeV, for which the seasonal variation effect in the solar
neutrino sample of events, formed by recoil electrons with kinetic energy
$T_{e} \geq T_{e,Th}$, is either maximal or very close to the maximal; it can
vary dramatically with $T_{e,Th}$. Measuring the seasonal effect in each one of
a large number of samples corresponding to different values of $T_{e,Th}$ from
the indicated interval, say, to $T_{e,Th} = 5; 6; 7;...; 11 MeV$, provides a
very effective test of the VO solution. Predictions for the magnitude of the
seasonal effect in such samples are given for a large set of representative
values of $\Delta m^2$ and $\sin^22\theta$ from the VO solution region.


title: Massive Meson Fluctuation in NJL Model

abstract:
  Based on the self-consistent scheme beyond mean-field approximation in the
large $N_c$ expansion, including current quark mass explicitly, a general
scheme of SU(2) NJL model is developed. To ensure the quark self-energy
expanded in the proper order of $N_c$, an approximate internal meson propagator
is deduced, which is in order of $O(1/N_c)$. In our scheme, adopting the method
of external momentum expansion, all the Feynman diagrams are calculated in a
unified way by only expanding the quark propagator. Our numerical results show,
that different from the mean field approximation in which the explicitly chiral
symmetry breaking is invisible, the effect of finite pion mass can be seen
clearly when beyond mean-field approximation.


title: The B -> X_s gamma Photon Spectrum

abstract:
  The photon energy spectrum in inclusive weak radiative B -> X_s gamma decay
is computed to order alpha_s^2 beta_0. This result is used to extract a value
for the HQET parameter $\bar\Lambda$ from the average <1-2E_\gamma/m_B>, and a
value of the parameter $\lambda_1$ from <(1-2E_\gamma/m_B)^2>. An accurate
measurement of <1-2E_\gamma/m_B> can determine the size of the nonperturbative
contributions to the Upsilon(1S) mass which cannot be absorbed into the b quark
pole mass.


title:
The role of resolved virtual photons in the production of forward jets
  at HERA

abstract:
  The measurement of forward jet cross sections has been suggested as a
promising probe of new small x parton dynamics and the question is whether the
new HERA data provide an indication of this. In this paper the influence of
resolved photon processes has been investigated and it has been studied to what
extent the inclusion of such processes in addition to normal deep inelastic
scattering leads to agreement with data. It is shown that two DGLAP evolution
chains from the hard scattering process towards the proton and the photon
respectively, are sufficient to describe effects observed in the HERA data,
which have been attributed to BFKL dynamics.


title: Two-loop Compton and annihilation processes in thermal QCD

abstract:
  We calculate the Compton and annihilation production of a soft static lepton
pair in a quark-gluon plasma in the two-loop approximation. We work in the
context of the effective perturbative expansion based on the resummation of
hard thermal loops. Double counting is avoided by subtracting appropriate
counterterms. It is found that the two-loop diagrams give contributions of the
same order as the one-loop diagram. Furthermore, these contributions are
necessary to obtain agreement with the naive perturbative expansion in the
limit of vanishing thermal masses.


title: CP-violation in neutrino oscillations

abstract:
  We study in a quantitative way CP-violating effects in neutrino oscillation
experiments in the light of current and future data. Different scenarios with
three and four neutrinos are worked out in detail including matter effects in
long baseline experiments and it is shown that in some cases CP-violating
effects could affect the analysis of a possible measurement. In particular in
the three neutrino case we find that the effects can be larger than expected,
at least in long-baseline $\nu_\mu\to\nu_e$. Moreover, measuring these effects
could give useful information on the solar oscillation frequency. In four
neutrino scenarios large effects are possible both in the $\nu_\mu\to\nu_\tau$
and $\nu_\mu\to\nu_e$ channels of long-baseline experiments, whereas
short-baseline experiments are affected only marginally.


title: Supersymmetric Unification in the Light of Neutrino Mass

abstract:
  We argue that with the discovery of neutrino mass effects at Super-Kamiokande
there is a clear logical chain leading from the Standard Model through the MSSM
and the recently developed Minimal Left Right Supersymmetric models with a
renormalizable see-saw mechanism for neutrino mass to Left Right symmetric SUSY
GUTS : in particular, SO(10) and $SU(2)_L \times SU(2)_R\times SU(4)_c$. The
progress in constructing such GUTS explicitly is reviewed and their
testability/falsifiability by proton decay measurements emphasized.


title: Possible Sources of a Transient Natural Neutrino Flux

abstract:
  Recent observations of variability in the ``atmospheric neutrino'' rate place
constraints on possible explanations of the atmospheric neutrino anomaly. Many
proposed solutions to the problem are static and can not be adapted to the
temporal dependence observed. Nonatmospheric sources may be needed to explain
the variations.


title: Heavy Baryons - Different Facets of Experimental results

abstract:
  This paper reviews the experimental status of heavy baryons. It covers the
aspec ts of production, spectroscopy and decay presenting recent results
obtained in this fi eld. It closes with an outlook on further work on and with
heavy baryons and their po ssible role for other measurements.


title:
Nucleon-Quarkonium Elastic Scattering and the Gluon Contribution to
  Nucleon Spin

abstract:
  It is shown that the amplitude for the scattering of a heavy quarkonium
system from a nucleon near threshold is completely determined by the fraction
of angular momentum, as well as linear momentum, carried by gluons in the
nucleon. A form for the quarkonium-nucleon non-relativistic potential is
derived.


title: Theory of electroweak interactions without spontaneous symmetry breaking

abstract:
  The study of a EW theory without spontaneous symmetry breaking is presented.
A new symmetry breaking, axial-vector symmetry breaking, is found.
M^{2}_{W}=1/2g^{2}m^{2}_{t}, m^{2}_{Z}=\rho m^{2}_{W}/cos^{2} \theta, and
G_{F}=1/(2\sqrt{2}m^{2}_{t}) are obtained and they agree with data. It has been
proved that the theory is renormalizable and unitary.


title: The visible effect of a very heavy magnetic monopole at colliders

abstract:
  If a heavy Dirac monopole exists, the light-to-light scattering below the
monopole production threshold is enhanced due to strong coupling of monopoles
to photons. At the next Linear Collider with electron beam energy 250 GeV this
photon pair production could be observable at monopole masses less than 2.5-6.4
TeV in the $e^+e^-$ mode or 3.7-10 TeV in the $\gamma\gamma$ mode, depending on
the monopole spin. At the upgraded Tevatron such an effect is expected to be
visible at monopole masses below 1-2.5 TeV. The strong dependence on the
initial photon polarizations allows to find the monopole spin in experiments at
$e^+e^-$ and $\gamma\gamma$ colliders. We consider the $Z\gamma$ production and
the $3\gamma$ production at $e^+e^-$ and $pp$ or $p\bar{p}$ colliders via the
same monopole loop. The possibility to discover these processes is
significantly lower than that of the $\gamma\gamma$ case.


title:
Anomalous Quartic Couplings in W^+W^-\gamma, Z^0Z^0\gamma and
  Z^0\gamma\gamma Production at Present and Future e^+e^- Colliders

abstract:
  The production of three electroweak gauge bosons in high-energy $e^+e^-$
collisions offers a window on anomalous quartic gauge boson couplings. We
investigate the effect of three possible anomalous couplings on the cross
sections for $W^+W^-\gamma$, $Z^0Z^0\gamma$ and $Z^0\gamma\gamma$ productions
at LEP2 ($\sqrt{s} = 200$ GeV) and at a future linear collider ($\sqrt{s} =
500$ GeV). We find that the combination of energies and processes provides
reasonable discrimination between the various anomalous contributions.


title: Symmetry Conserving Dynamical Mappings

abstract:
  Using the concept of dynamical mappings, two symmetry conserving
nonperturbative approaches are presented. The first is based on the
1/N-expansion and sorted out using Holstein-Primakoff mapping. The second
consists of dynamically mapping the canonical fields into the corresponding
currents. It is argued, either by comparing the Fock spaces or the observables,
that the latter constitutes a higher approach which transcends the
1/N-expansion and contains the dynamics generated by the Gaussian functional
approach.


title: L-R asymmetries and signals for new bosons

abstract:
  Several left-right parity violating asymmetries in lepton-lepton scattering
in fixed target and collider experiments are considered as signals for doubly
charged vector bosons (bileptons).


title: Baryogenesis at the QCD Scale

abstract:
  We propose a new mechanism for explaining the observed asymmetry between
matter and antimatter, based on nonperturbative physics at the QCD scale. Our
mechanism is a charge separation scenario, making use of domain walls
separating the recently discovered long-lived metastable vacua from the lowest
energy vacuum. The walls acquire a fractional negative baryon charge, leaving
behind a compensating positive baryon charge in the bulk. The regions of
metastable vacuum bounded by walls ("B-shells") will contribute to the dark
matter of the Universe.


title: Late Inflation and the Moduli Problem of Sub-Millimeter Dimensions

abstract:
  We consider a recent model with sub-millimeter sized extra dimensions, where
the field that determines the size of the extra dimensions (the radion) also
acts as an inflaton. The radion is also a stable modulus, and its coherent
oscillations can potentially overclose the Universe. It has been suggested that
a second round of late inflation can solve this problem, however we find that
this scenario does not allow for sufficient reheating of the Universe.


title: A classical picture of lepton neutral current forces

abstract:
  When charged current weak interations are excluded, the neutral current weak
interaction is formally similar to ordinary electromagnetism with a massive
photon. In this spirit, the Maxwell equations for the fields of the Z-boson are
derived from the standard model. These describe the Z-boson scalar and vector
potentials, and the Z-boson electric and magnetic fields whose sources are
electron and neutrino distributions and currents. The Z-boson Maxwell equations
are solved for point sources representing classical point-like electrons and
neutrinos. The parity violation of the weak interation is manifest in the
structure of these solutions. As an application of this model, the neutral
current contribution to the muonium hyperfine structure is computed using
nonrelativistic perturbation theory.


title: A Hamiltonian Model for Hard Inelastic Hadronic Collisions

abstract:
  Hamiltonian eikonal model for multiple production in high energy
hadron-hadron collisions is presented and worked out with the aim of providing
a simple frame for various different observables. An important role is played
by unitarity which is built in by construction in the Hamiltonian formulation.
The eikonal approximation allows both a very effective simplification of the
dynamics, and facilitates the discussion on the relevance of possible spatial
inhomogeneities of the hadrons. The model is intended to describe only the hard
interaction of the constituents, the structure of the incoming hadrons and the
final hadronization processes are outside the scope of the present
investigation.


title: Axial Contributions at the Top Threshold

abstract:
  We calculate the contributions of the axial current to top quark pair
production in e+ e- annihilation at threshold. The QCD dynamics is taken into
account by solving the Lippmann-Schwinger equation for the P wave production
using the QCD potential up to two loops. We demonstrate that the dependence of
the total and differential cross section on the polarization of the e+ and e-
beams allows for an independent extraction of the axial current induced cross
section.


title: PQCD analysis of exclusive B meson decays

abstract:
  The perturbative QCD formalism for exclusive heavy meson decays, especially
the three-scale factorization theorem for nonleptonic modes is reviewed and
compared to the conventional Bauer-Stech-Wirbel model.


title:
Remarks on Cosmic String Formation during Preheating on Lattice
  Simulations

abstract:
  We reconsider the formation of (global) cosmic strings during and after
preheating by calculating the dynamics of a scalar field on both two- and
three- dimensional lattices. We have found that there is little differences
between the results in two and three dimensions about the dynamics of
fluctuations, at least, during preheating. Practically, it is difficult to
determine whether long cosmic strings which may affect the later evolution of
the universe could ever be produced from the results of simulations on
three-dimensional lattices with smaller box sizes than the horizon. Therefore,
using two-dimensional lattices with large box size, we have found that cosmic
strings with the breaking scale 0\eta \sim 10^{16} GeV are produced for broad
range of parameter space in \eta, while for higher breaking scales (\eta \sim
3\times 10^{16} GeV), their production depends crucially on the value of the
breaking scale \eta in our simulations.


title: Radiative Effects in the Processes of Hadron Electroproduction

abstract:
  An approach to calculate radiative corrections to unpolarized cross section
of semi-inclusive electroproduction is developed. An explicit formulae for the
lowest order QED radiative correction are presented. Detailed numerical
analysis is performed for the kinematics of experiments at the fixed targets.


title:
Form Factors and Decay Rates for Heavy $\Lambda$ Semileptonic Decays
  from QCD Sum Rules

abstract:
  QCD sum rules for the determination of form factors of $\Lambda_b$ and
$\Lambda_c$ semileptonic decays are investigated. With a form for the baryonic
current appropriate for the limits of the heavy quark symmetries, the different
tensor structures occurring in the two- and three-point functions are
separately studied, and in each case general relations are written for the form
factors. Particular attention is given to the treatment of the kinematical
region ascribed to the continuum. The $t$-dependence of the form factors and
the decay rates are numerically evaluated and compared to experimental
information.


title: Diagonal input for the evolution of off-diagonal partons

abstract:
  We show that a knowledge of diagonal partons at a low scale is sufficient to
determine the off-diagonal (or skewed) distributions at a higher scale, to a
good degree of accuracy. We quantify this observation by presenting results for
the evolution of off-diagonal distributions from a variety of different inputs.


title: Threshold expansion of the sunset diagram

abstract:
  By use of the threshold expansion we develop an algorithm for analytical
evaluation, within dimensional regularization, of arbitrary terms in the
expansion of the (two-loop) sunset diagram with general masses m_1, m_2 and m_3
near its threshold, i.e. in any given order in the difference between the
external momentum squared and its threshold value, (m_1+m_2+m_3)^2. In
particular, this algorithm includes an explicit recurrence procedure to
analytically calculate sunset diagrams with arbitrary integer powers of
propagators at the threshold.


title: Coherence and the Day - Night Asymmetry in the Solar Neutrino Flux

abstract:
  We consider the day-night asymmetries predicted by MSW solutions of the solar
neutrino problem. The integration over the neutrino energy, as well as over the
production region or over the time intervals of more than a day leads to the
averaging of oscillations on the way to the earth. This is equivalent to
considering the neutrino state arriving at the surface of the earth as an
incoherent mixture of the neutrino mass eigenstates (even if there is no
divergence of wavepackets). As a consequence, the $\nu_e$-regeneration effect
inside the earth is incoherent, in contrast with the result in hep-ph/9902435.


title: Amplitudes for Higgs Bosons plus Four Partons

abstract:
  In this talk we consider amplitudes for processes involving a Higgs boson,
either scalar or pseudoscalar, plus four light partons. These amplitudes are
relevant to the production of a Higgs boson plus two jets in hadronic
collisions. They are also relevant to calculating the transverse momentum
spectrum for Higgs bosons at next-to-leading order in the strong coupling. We
work in the limit that the top quark is much heavier than the Higgs bosons and
use effective Lagrangians for the interactions of gluons with the Higgs bosons.
We present the amplitudes involving a Higgs boson and: 1) four gluons, 2) two
quarks and two gluons; and 3) four quarks. We show that the pseudoscalar
amplitudes are nearly identical to those for the scalar case, the only
differences being the overall size and the relative signs between terms.


title:
Eikonalised minijet model predictions for cross-sections of photon
  induced processes

abstract:
  In this talk I present the results of an analysis of total and inelastic
hadronic cross-sections for photon induced processes in the framework of an
eikonalised minijet model(EMM). We fix the various input parameters to the EMM
calculations by using the data on photoproduction cross-sections and then make
predictions for $\siggmhad$ using same values of the parameters. We then
compare our predictions with the recent measurements of $\siggmhad$ from LEP.
We also show that in the framework of the EMM the rise with $\rts$ of the
total/inelastic cross-sections will be faster for photon induced processes than
for the processes induced by hadrons like protons.


title: The $\rho - \pi$ Puzzle of J/\psi and \psi' Decays

abstract:
  The recent BES Collaboration data on $\psi' \ra PV$, particularly the isospin
violating mode $\psi' \ra \pi^0 \omega^0$ and finding of a finite number for
$B(\psi' \ra K^{*0}\bar{K}^0)$, enable us now to deal more precisely about the
challenges to theory concerning this extraordinary and remarkable so called
$\rho - \pi$ Puzzle of $J/\psi$ and $\psi'$ Decays. In terms of existing data,
and deploying the simplest phenomenology, measurement of $\psi' \ra \pi^+\pi^-$
and whether a finite number for the $K^{*+} K^-$ mode might require a
significantly larger accumulation of data, remain interesting questions.


title:
The Reach of Tevatron Upgrades in Gauge-Mediated Supersymmetry Breaking
  Models

abstract:
  We examine signals for sparticle production at the Tevatron within the
framework of gauge mediated supersymmetry breaking models for four different
model lines, each of which leads to qualitatively different signatures. We
identify cuts to enhance the signal above Standard Model backgrounds, and use
ISAJET to evaluate the SUSY reach of experiments at the Fermilab Main Injector
and at the proposed TeV33. For the model lines that we have examined, we find
that the reach is at least as large, and frequently larger, than in the mSUGRA
framework. For two of these model lines, we find that the ability to identify
$b$-quarks and $\tau$-leptons with high efficiency and purity is essential for
the detection of the signal.


title:
Quark and Lepton Mass Matrices in the SO(10) Grand Unified Theory with
  Generation Flipping

abstract:
  We investigate the SO(10) grand unified model with generation flipping. The
model contains one extra matter multiplet $\psi(10)$ and it mixes with the
usual matter multiplets $\psi_i(16)$ when the SO(10) is broken down to SU(5).
We find the parameter region of the model in which the observed quark masses
and mixings are well reproduced. The resulting parameter region is consistent
with the observation that only $\psi_i(16)$ have a source of hierarchies and
indicates that the mixing between second and third generations tends to be
large in the lepton sector, which is consistent with the observed maximal
mixing of the atmospheric neutrino oscillation. We also show that the model can
accommodate MSW and vacuum oscillation solutions to the solar neutrino deficit
depending on the form of the Majorana mass matrix for the right-handed
neutrinos.


title: A more careful estimate of the charm content of eta'

abstract:
  We estimate the quantity |f_eta'^(c)| which is associated with the charm
content of eta' meson from the experimentally known ratio R=B(psi ->eta' gamma
)/B(psi ->eta_c gamma). It is shown that due to the off-shellness of the c\bar
c component of eta', which has been overlooked so far, f_eta'^(c) is further
suppressed. Assuming that psi ->eta' gamma decay is dominated by psi ->eta_c
transition, we obtain |f_eta'^(c)| = 2.4 MeV which could imply that the (b ->
c\bar cs) mechanism does not play a major role in the B -> K eta' decay mode.


title: About spin precession in electromagnetic wave

abstract:
  It is shown that two ways of the description of the 1/2-spin precession in a
circularly polarized electromagnetic wave: on the basis of the
Bargmann-Michel-Telegdi equation and on the basis of the Dirac equation with
Pauli term give the same result in the second order on the wave's field for
arbitrary wave length.


title: Radiatively Generated Parton Distributions of Real and Virtual Photons

abstract:
  The parton content of real (P^2=0) and virtual (P^2\neq 0) transverse photons
\gamma(P^2) is expressed in terms of perturbative pointlike and nonperturbative
hadronic (VMD) components, employing recently updated parton distributions of
pions and protons. The resulting parameter-free and perturbatively stable LO
and NLO parton densities f^{\gamma(P^2)}(x,Q^2) are smooth in P^2 and apply to
all P^2 >= 0 whenever \gamma(P^2) is probed at scales Q^2 >> P^2 where
transverse photons also dominate physically relevant cross sections.
Predictions are given for the structure function F_2^{\gamma(P^2)}(x,Q^2) and
f^{\gamma(P^2)}(x,Q^2), and are compared with all relevant data for real
photons as well as with recent data for virtual photons as extracted from DIS
ep dijet events. Simple analytic parametrizations of our predicted parton
distributions are presented for the real photon in LO and NLO, and for the
virtual photon in LO which, within sufficient accuracy, may be also used in
NLO-QCD.


title:
Event-by-event fluctuations in heavy-ion collisions and the quark-gluon
  string model

abstract:
  We apply dynamical string models of heavy-ions collisions at high energies to
the analysis of event-by-event fluctuations. Main attention is devoted to a new
variable proposed to study "equilibration" in heavy-ions collisions. Recent
results of the NA49 collaboration at CERN SPS are compared with predictions of
the Quark-Gluon String Model (QGSM), which gives a good description of
different aspects of multiparticle production for collisions of nucleons and
nuclei. It is shown that the new observable and other results of the NA49
analysis of event-by-event fluctuations are correctly reproduced in the model.
We discuss dynamical effects responsible for these fluctuations and give the
predictions for p-p, p-Pb and Pb-Pb collisions at RHIC and higher energies.


title:
Large-order trend of the anomalous-dimensions spectrum of trilinear
  twist-3 quark operators

abstract:
  The anomalous dimensions of trilinear-quark operators are calculated at
leading twist $t=3$ by diagonalizing the one-gluon exchange kernel of the
renormalization-group type evolution equation for the nucleon distribution
amplitude. This is done within a symmetrized basis of Appell polynomials of
maximum degree $M$ for $M\gg 1$ (up to order 400) by combining analytical and
numerical algorithms. The calculated anomalous dimensions form a degenerate
system, whose upper envelope shows asymptotically logarithmic behavior.


title: Neutrino Oscillations in a Predictive SUSY GUT

abstract:
  In this letter we present a predictive SO(10) SUSY GUT with flavor symmetry
U(2) \times U(1) which has several nice features. We are able to fit fermion
masses and mixing angles, including recent neutrino data, with 9 parameters in
the charged fermion sector and 4 in the neutrino sector. The flavor symmetry
plays a preeminent role -- (i) The model is "natural" -- we include all terms
allowed by the symmetry. It restricts the number of arbitrary parameters and
enforces many zeros in the effective mass matrices. (ii) Flavor symmetry
breaking from U(2) \times U(1) \to U(1) \to nothing generates the family
hierarchy. It also constrains squark and slepton mass matrices, thus
ameliorating flavor violation resulting from squark and slepton loop
contributions. (iii) Finally, it naturally gives large angle $\nu_\mu -
\nu_\tau$ mixing describing atmospheric neutrino oscillation data and small
angle $\nu_e - \nu_{s}$ mixing consistent with the small mixing angle MSW
solution to solar neutrino data.


title:
Extracting the dipole cross-section from photo- and electro-production
  total cross-section data

abstract:
  We report on a successful attempt to extract the cross-section for the
high-energy scattering of colour dipoles of fixed transverse size off protons
using electroproduction and photoproduction total cross-section data, subject
to the constraint provided by the ratio of the overall photon dissociation
cross-section to the total cross-section.


title: Implications of a $\chi(3.86)$ State for Theoretical Models

abstract:
  Recent preliminary evidence for a $D \bar{D}$ state $\chi(3.86)$ raises
extremely interesting implications for theoretical models, particularly those
currently in vogue, e.g. the flux tube model and a molecular charmonium
picture. We examine the experimental consequences as well as the possible
unveiling of a strata of C-exotic states in heavy quarkonia systems by future
facilities like BES Upgrade/Tau-Charm Factory and CLEO III/B-Factories.


title: CP Violation in B Decays in a 2-Higgs Doublet Model for the Top Quark

abstract:
  In the absence of natural flavor conservation, multi-Higgs doublet models
generally contain new sources of CP violation and anomalous charged Higgs
Yukawa couplings. We present a charged-Higgs CP violation study of one such
two-Higgs doublet model (2HDM) which treats the top quark differently from the
other quarks. The phenomenological implications for the K-Kbar system and for B
decays differ significantly from those of the standard model (SM) and of the
2HDM's with natural flavor conservation. In particular, the SM phase in this
model could take a wide range of values, and the CP asymmetry in the
"gold-plated" decay mode B to J/psi K_S could be quite different from and even
of opposite sign relative to the SM prediction. A new mechanism is also noted
for generating a large neutron electric dipole moment which is close to the
present experimental limit.


title:
Vector-like family extension of the standard model and the light quark
  masses and mixings

abstract:
  The standard model extended with the pairs of the vector-like families is
studied. The model independent analysis for an arbitrary case and an explicit
realization for the case with one pair of the heavy vector-like families are
considered. The mixing matrices of the light quarks for the left- and
right-handed charged currents, as well as those for the flavour changing
neutral currents, both the Z and Higgs mediated, are found.


title:
The rare decays $B \to X_{s,d} \nu \bar \nu$ and $B_{s,d} \to l^+l^- $
  in the Multiscale Walking Technicolor Model

abstract:
  We calculate the contributions to the rare B-decays, $B \to X_{s,d} \nu \bar
\nu$, $B_{s,d} \to l^+l^- $ from the unit-charged technipions. Within the
considered parameter space we find that: (a) the enhancements to the branching
ratios in question can be as large as three orders of magnitude; (b) the ALEPH
data of $B \to X_s \nu \bar \nu$ lead to strong mass bounds on $m_{p1}$ and
$m_{p8}$: $m_{p8} \geq 620, 475 GeV$ for $F_Q=40GeV$ and $m_{p1}=100, 400 GeV$
respectively. (c) the CDF data of $B_s \to \mu \bar \mu$ lead to a relatively
weak limit: $m_{p8} \geq 320 GeV$ for $F_Q=40GeV$ and $m_{p1}=200 GeV$.


title:
Rare decays $B \to X_{s,d} \nu \bar \nu$ and $B_{s,d} \to l^+ l^-$ in
  the Topcolor-assisted Technicolor Model

abstract:
  We calculate the contributions to the rare decays $B \to X_{s,d} \nu \bar
\nu$ and $B_{s,d} \to l^+l^-$ from one-loop $Z^0$-penguin diagrams in the
framework of Topcolor-assisted Technicolor Model. Within the parameter space,
we find that: (a) the new contribution from technipions is less than 2% of the
standard model prediction; (b) the top-pions can provide a factor of 10 to 30
enhancement to the ratios in question; (c) the topcolor-assisted technicolor
model is consistent with the current experimental data.


title: The rare K-decays in the Multiscale Walking Technicolor Model

abstract:
  We calculate the one-loop $Z^0$-penguin contributions to the rare K-decays,
$K^+ \to \pi^+ \nu \bar \nu$, $K_L \to \pi^0 \nu \bar \nu$ and $K_L \to \mu^+
\mu^-$, from the unit-charged technipions $\pi_1$ and $\pi_8$ in the framework
of the Multiscale Walking Technicolor Model. We find that: (a) the $\pi_1$ and
$\pi_8$ can provide one to two orders enhancements to the branching ratios of
the rare K-decays; (b) by comparing the experimental data of $Br(K^+ \to \pi^+
\nu \bar \nu)$ with the theoretical prediction one finds the lower mass bounds,
$m_{p8} \geq 249 GeV$ for $F_Q=40GeV$ and $m_{p1}=100 GeV$; (c) by comparing
the experimental data of $Br(K_L \to \mu^+ \mu^-)$ with the theoretical
predictions one finds the lower bounds on $m_{p1}$ and $m_{p8}$, $m_{p1} \geq
210 GeV$ if only the contribution from $\pi_1$ is taken into account, and
$m_{p8} \geq 580 GeV$ for $m_{p1}=210 GeV$, assuming $F_Q=40GeV$; (d) the
assumed ranges of the masses $m_{p1}$ and $m_{p8}$ in the Multiscale Walking
Technicolor Model are excluded by the rare K-decay data.


title:
The rare K-decays and $Z^0$-penguin contributions in the
  Topcolor-assisted technicolor models

abstract:
  We calculate the new contributions to the rare decays $K^+ \to \pi^+ \nu \bar
\nu$, $K_L \to \pi^0 \nu \bar \nu$ and $K_L \to \mu^+ \mu^-$ from new
$Z^0$-penguin and box diagrams induced by the unit-charged scalars
$(\tilde{\pi}^\pm, \tilde{H}^\pm, \pi_1^\pm, \pi_8^\pm)$ appeared in the
Topcolor-assisted technicolor (TC2) models. We find that: (a) the unit-charged
top-pion $\tilde{\pi}^\pm$ and b-pion $\tilde{H}^\pm$ can provide large
contributions to the rare K-decays if they are relatively light; (b) the size
of mixing elements $D_{L,R}^{ij}$ ($i \neq j$) is strongly constrained by the
data of $B^0$ meson mixing: $|a_R^{ts}|, |a_R^{td}| < 0.01$ for
$a_L^{td}=a_L^{ts}=1/2$ and $m_{\tilde{H}^0}\leq 600GeV$; (c) the enhancements
to the branching ratios of rare K-decays from new scalars can be as large as
one order of magnitude; (d) there is a strong cancellation between the short-
and long-distance dispersive part of the decay $K_L \to \mu^+ \mu^-$, the
constraint on the new short-distance part from this decay mode is thus not
strong; (e) the typical TC2 model under study is generally consistent with the
available rare K-decay data.


title: Covariant amplitudes for mesons

abstract:
  We show how to construct covariant amplitudes for processes involving higher
spins in this paper. First we give the explicit expressions of Rarita-Schwinger
wave functions and propagators for bosons with spins, then kinematic
singularity free 3-leg effective vertexes are derived and given in a list.
Equivalence relations are worked out to get these independent vertexes.
Constraints of space reflection symmetry and boson symmetry are considered and
shown in a explicit way. Some helicity amplitudes for two-body decays in center
of frame are calculated. Finally the covariant helicity amplitudes for the
process $a_1\to \pi^+\pi^+\pi^-$ are constructed to illustrate how to include
background (1PI) amplitudes. Both background amplitudes and resonance
amplitudes are needed to give reliable descriptions to high energy reactions.


title: Inflation and Preheating in NO models

abstract:
  We study inflationary models in which the effective potential of the inflaton
field does not have a minimum, but rather gradually decreases at large $\phi$.
In such models the inflaton field does not oscillate after inflation, and its
effective mass becomes vanishingly small, so the standard theory of reheating
based on the decay of the oscillating inflaton field does not apply. For a long
time the only mechanism of reheating in such non-oscillatory (NO) models was
based on gravitational particle production in an expanding universe. This
mechanism is very inefficient. We will show that it may lead to cosmological
problems associated with large isocurvature fluctuations and overproduction of
dangerous relics such as gravitinos and moduli fields. We also note that the
setting of initial conditions for the stage of reheating in these models should
be reconsidered. All of these problems can be resolved in the context of the
recently proposed scenario of instant preheating if there exists an interaction
${g^2} \phi^2\chi^2$ of the inflaton field $\phi$ with another scalar field
$\chi$. We show that the mechanism of instant preheating in NO models is much
more efficient than the usual mechanism of gravitational particle production
even if the coupling constant $g^2$ is extremely small, $10^{-14} \ll g^2 \ll
1$.


title: Festschrift to the 60th Birthday of J. Pisut

abstract:
  This WWW page contains links to contributions that appear in the Festschrift
issue of the journal Acta Physica Slovaca dedicated to Professor Jan Pisut on
the occasion of his 60th birthday. Where available, links are given also to
e-prints in xxx archives.


title: Proton Polarization Shifts in Electronic and Muonic Hydrogen

abstract:
  The contribution of virtual excitations to the energy levels of electronic
and muonic hydrogen is investigated combining a model-independent approach for
the main part with quark model predictions for the remaining corrections.
Precise values for the polarization shifts are obtained in the long-wavelength
dipole approximation by numerically integrating over measured total
photoabsorption cross sections. These unretarded results are considerably
reduced by including retardation effects in an approximate way since the
average momentum transfer (together with the mean excitation energy) turns out
to be larger than usually assumed. Transverse and seagull contributions are
estimated in a simple harmonic oscillator quark model and found to be
non-negligible. Possible uncertainties and improvements of the final results
are discussed.


title: High Temperature Resummation in the Linear $\delta$-Expansion

abstract:
  The optimized linear $\delta$-expansion is applied to the $\lambda \phi^4$
theory at high temperature. Using the imaginary time formalism the thermal mass
is evaluated perturbatively up to order $\delta^2$. A variational procedure
associated with the method generates nonperturbative results which are used to
obtain the critical temperature for the phase transition. Our results are
compared with the ones given by propagator dressing methods.


title:
Time-reversal odd fragmentation and distribution functions in pp and ep
  single spin asymmetries

abstract:
  We present some estimates of T-odd fragmentation and distribution functions,
$H_1^\perp$ and $f_{1T}^{\perp}$, evaluated on the basis of a fit on
experimental data in p$^\uparrow$p. Assuming the T-odd fragmentation function
to be responsible for the single spin asymmetry in pion production in
p$^\uparrow$p, we find the ratio $H_1^{\perp}/D_1$ to be in good agreement with
the experimental results from DELPHI data on Z -> 2$-jet decay. We use our
estimates to make predictions for ep$^\uparrow$.


title: The infrared behaviour of the static potential in perturbative QCD

abstract:
  The definition of the quark-antiquark static potential is given within an
effective field theory framework. The leading infrared divergences of the
static singlet potential in perturbation theory are explicitly calculated.


title: Massive Neutrino Decays

abstract:
  Neutrino physics is used as an illustrative example for an elementary
introduction to the computational method of Feynman loop-diagrams and decay
rates. If the neutrinos are as massive as recently reported by the
Super-Kamiokande results, the heaviest neutrino $\nu_H$ would not be stable.
Although chargeless, it could decay -- by quantum loop effect -- into a lighter
neutrino $ \nu_L$ by emitting a photon: $\nu_H \to \nu_L + \gamma $. If
kinematically possible, the $\nu_H \to \nu_L$ + e$^+$ + e$^-$ mode could occur
at the tree diagram level and furthermore get enhanced, at one-loop radiative
corrections, by a large logarithm of the electron mass acting as an infrared
cutoff.


title: Minimal Gauge Invariant Classes of Tree Diagrams in Gauge Theories

abstract:
  We describe the explicit construction of groves, the smallest gauge invariant
classes of tree Feynman diagrams in gauge theories. The construction is valid
for gauge theories with any number of group factors which may be mixed. It
requires no summation over a complete gauge group multiplet of external matter
fields. The method is therefore suitable for defining gauge invariant classes
of Feynman diagrams for processes with many observed final state particles in
the standard model and its extensions.


title: Saturation in Diffractive Deep Inelastic Scattering

abstract:
  We successfully describe the HERA-data on diffractive deep inelastic
scattering using a saturation model which has been applied in our earlier
analysis of the inclusive $ep$-scattering data. No further parameters are
needed. Saturation already turned out to be essential in describing the
transition from large to small values of $Q^2$ in inclusive scattering. It is
even more important for diffractive processes and naturally leads to a constant
ratio of the diffractive versus inclusive cross sections. We present an
extensive discussion of our results as well as detailed comparison with data.


title:
Chiral Phase Transition for SU(N) Gauge Theories via an Effective
  Lagrangian Approach

abstract:
  We study the chiral phase transition for vector-like SU(N) gauge theories as
a function of the number of quark flavors N_f by making use of an
anomaly-induced effective potential. We modify an effective potential of a
previous work, suggested for N_f < N, and apply it to larger values of N_f
where the phase transition is expected to occur. The new effective potential
depends explicitly on the full \beta-function and the anomalous dimension
\gamma of the quark mass operator. By using this potential we argue that chiral
symmetry is restored for \gamma <1. A perturbative computation of \gamma then
leads to an estimate of the critical value N_f^c for the transition.


title: Measuring the Higgs Boson Yukawa Couplings at an NLC

abstract:
  We investigate the inclusive production of the Higgs boson with a heavy quark
pair, $t {\bar t}$ or $b {\bar b}$, in e^+e^- collisions at high energy. The
${\cal O}(\alpha_s)$ QCD corrections are included.


title: Hadronic Three Jet Production at Next-to-Leading Order

abstract:
  We report preliminary results for a next-to-leading order event generator for
hadronic three jet production. We demonstrate the stability of the calculation
and present preliminary results for the jet transverse energy spectra. This is
the first calculation of three jet production at this order to include all
parton sub-processes.


title: Charge assignments in multiple-U(1) gauge theories

abstract:
  We discuss the choice of gauge field basis in multiple-U(1) gauge theories.
We find that there is a preferred basis, specified by the charge orthogonality
condition, in which the U(1) gauge fields do not mix under one-loop
renormalization group running.


title: Can \epsilon'/\epsilon be supersymmetric?

abstract:
  The possible supersymmetric contribution to \epsilon'/\epsilon has been
generally regarded small in the literature. We point out, however, that this is
a result based on specific assumptions, such as universal scalar mass, and in
general needs not to be true. Based on a general situation, (1) hierarchical
quark Yukawa matrices protected by flavor symmetry, (2) generic dependence of
Yukawa matrices on Polonyi/moduli fields as expected in many
supergravity/superstring theories, (3) Cabibbo rotation originating from the
down-sector, and (4) phases of order unity, we find the typical supersymmetric
contribution to \epsilon'/\epsilon to be order 3x10^-3 for m_{\tilde{q}} = 500
GeV. It is even possible that the supersymmetric contribution dominates in the
reported KTeV value \epsilon'/\epsilon = (28 \pm 4.1)x10^-4. If so, the neutron
electric dipole moment is likely to be within the reach of the currently
planned experiments.


title: Asymptotic behaviour of the gluon propagator from lattice QCD

abstract:
  We study the flavorless gluon propagator in the Landau gauge from high
statistics lattice calculations. Hypercubic artifacts are efficiently
eliminated by taking the $\sum p_\mu^4 \to 0$ limit. The propagator is fitted
to the three-loops perturbative formula in an energy window ranging form $\sim$
2.5 GeV up to $\sim$ 5.5 GeV. $\alpha_s$ is extracted from the best fit in a
continuous set of renormalisation schemes. The fits are very good, with a
$\chi^2$ per d.o.f smaller than 1. We propose a more stringent test of
asymptotic scaling based on scheme independence of the resulting $\Lambda_{\bar
MS}$. This method shows that asymptotic scaling at three loops is not reached
by the gluon propagator although we use rather large energies. We are only able
to obtain an effective flavorless three-loops estimate $\Lambda_{\bar
MS}^{(3)}= 353 \pm 2 ^{+25}_{-10} $ MeV. We argue that the real asymptotic
value for $\Lambda_{\bar MS}$ should plausibly be smaller.


title: Non-standard soft supersymmetry breaking

abstract:
  We explore a more general class of soft supersymmetry-breaking masses and
interactions than that usually considered, both in general and in the MSSM
context, where our results for the one-loop $\beta$-functions correct some
errors in the literature. We identify a new class of one-loop finite
supersymmetric theories.


title: Rescattering Effects in Heavy Quark Decays

abstract:
  We review some recent developments in the studies of direct CP violation and
final state interactions in weak decays of heavy quarks.


title: K\bar{K}-Continuum and Isoscalar Nucleon Form Factors

abstract:
  We analyse the isoscalar vector current form factors of the nucleon using
dispersion relations. In addition to the usual vector meson poles, we account
for the K\bar{K}-continuum contribution by drawing upon a recent analytic
continuation of KN scattering amplitudes. For the Pauli form factor all
strength in the \phi region is already given by the continuum contribution,
whereas for the Dirac form factor additional strength in the \phi region is
required. The pertinent implications for the leading strangeness moments are
demonstrated as well. We derive a reasonable range for the leading moments
which is free of assumptions about the asymptotic behavior of the form factors.
We also determine the \phiNN coupling constants from the form factor fits and
directly from the K\bar{K} -> N\bar{N} partial waves and compare the resulting
values.


title: D0 mixing at CLEO II

abstract:
  The CLEO collaboration reported the observation of the ``wrong sign'' decay
D0 -> K+ pi- in 1993. Recent upgrades to the CLEO detector, including the
installation of a silicon vertex detector, have increased the sensitivity of
the detector to D0 -> K+ pi-. Using 5.6 fb-1 of data we report a preliminary
measurement of the rate of the wrong sign decay D0 -> K+ pi-, to be BR(D0 -> K+
pi-)/BR(D0 -> K- pi+) = (0.31 +/- 0.09 +/- 0.07)%. Additionally, combining this
measurement with D0 proper lifetime information we set a limit on D0 - D0bar
mixing of BR(D0 -> D0bar -> K+ pi-)/BR(D0 -> K- pi+) < 1.1% @ 90% confidence
limit.


title: Technihadron Production and Decay in Low-Scale Technicolor

abstract:
  We discuss the production and decay rates of the lightest color-singlet
technihadrons, spin-one rho_T and omega_T and spin-zero pi_T, in a minimal
``straw-man'' model of low-scale techicolor. The revised rho_T and omega_T
decay rates affect the technicolor searches planned for Run II of the Tevatron
Collider.


title:
The Reach of Fermilab Tevatron Upgrades for SU(5) Supergravity Models
  with Non-universal Gaugino Masses

abstract:
  We explore the reach of luminosity upgrades of the Fermilab Tevatron collider
for SU(5) supergravity models in which non-universal GUT-scale gaugino masses
arise via a vacuum expectation value for the auxiliary component of a
superfield that transforms as a 24, 75 or 200 dimensional representation of
SU(5). This results in a different pattern of sparticle masses and mixing
angles from what is expected in the minimal supergravity model (mSUGRA) with
universal GUT scale gaugino masses. We find that the resulting signal cross
sections, and hence the reach of the Tevatron, are sensitive to the gaugino
masses at the GUT scale. In the 24 model, the large splitting amongst the two
lightest neutralinos leads to SUSY events containing many isolated leptons,
including events with a real leptonic Z boson plus jets plus missing energy
signal which is visible over much of parameter space. In contrast, in the 75
and 200 models, the reach via leptonic SUSY signals is greatly reduced relative
to mSUGRA, and the signal is usually visible only via the canonical $\eslt
+$jets channel.


title: Phenomenology Remarks in M-theory on $S^1/Z_2$

abstract:
  In the simplest compactification, we discuss the intermediate unification in
M-theory on $S^1/Z_2$, and point out that we can push the eleven dimension
Planck scale to the TeV range if the gauge coupling in the hidden sector is
super weak, and the particles in the hidden sector might become candidates of
dark matter. We also discuss the soft terms in non-standard embedding. To the
next leading order, we compactify the perfect square and calculate the
gravitino mass. Furthermore, we give the general K\"ahler potential, gauge
kinetic function and superpotential if the next order correction is very large,
i. e., ${{\alpha T}\over S}$ is close to 1.


title:
Technihadron Production and Decay Rates in the Technicolor Straw Man
  Model

abstract:
  We present hadron collider production rates for the lightest color-singlet
technihadrons in a simple ``straw-man'' model of low-scale technicolor. These
rates are presented in a way to facilitate their encoding in PYTHIA. This
document is a companion to my paper, ``Technihadron Production and Decay in
Low-Scale Technicolor''.


title:
Second Loop Corrections from Superheavy Gauge Sector to Gauge Coupling
  Unification

abstract:
  We deal with extensions of the Standard Model by adding horizontal
interactions between particle generations. We calculate two loop corrections
caused by the presence of coupling between hypothetical horizontal gauge bosons
and matter fields, both at low and high energy. It is proved numerically, that
the coupling of such extra bosons does not affect the positive features of
unified and extended standard models with horizontal symmetry discussed in
former publications.


title: Implications of TeV scale SU(4)xSU(2)_LxSU(2)_R quark-lepton unification

abstract:
  The alternative $SU(4) \otimes SU(2)_L \otimes SU(2)_R$ gauge model, which
allows unification of the quarks and leptons at the TeV scale, is studied in
detail. We discuss the implications for nucleon decay, B and K rare meson
decays and neutrino masses. We also explain how this model solves the gauge
hierarchy problem without using supersymmetry or extra large dimensions.


title: Virtual photons in baryon chiral perturbation theory

abstract:
  We construct the general Lagrangian for relativistic and heavy baryon chiral
perturbation theory with virtual photons to fourth order. We work out the
electromagnetic and strong isospin violating contributions to the nucleon
self-energy, the nucleon mass and the scalar form factor of the nucleon.
Electromagnetic effects for the shift to the Cheng-Dashen point can be as large
as 2 MeV. We also discuss the corrections to Weinberg's prediction for the
scattering length difference $a(\pi^0 p) - a(\pi^0 n)$ and show that they are
small.


title:
One-loop quark and squark corrections to the lightest chargino pair
  production in photon-photon collisions

abstract:
  We present the detailed analytical and numerical investigations of the
one-loop radiative corrections of all quarks and squarks in the MSSM to the
lightest chargino pair production via $\gamma \gamma$ fusion at the future NLC.
The numerical corrections show that the cross sections of the subprocess and
the parent process are typically enhanced by several percent. We studied also
the effects induced by the CP violating complex phases stemming from squark and
chargino mass matrices in the MSSM at one-loop level.


title:
Photon Plus Jet Production in Large-Q2 ep Collisions at Next-to-Leading
  Order QCD

abstract:
  The production of photons accompanied by jets in large-Q2 deep inelastic ep
scattering is calculated in next-to-leading order. We describe how to
consistently include contributions from quark-to-photon fragmentation and give
numerical results relevant for HERA experiments.


title: Study of Gamma + Pi --> Pi + Pi

abstract:
  The problem of Gamma + Pi --> Pi + Pi is studied using the axial anomaly,
elastic unitarity, analyticity and crossing symmetry. Single variable
dispersion relation is assumed. Using elastic unitarity relation, an integral
equation equation for the lowest partial wave amplitude is obtained. The
solution for this integral equation is obtained by an iteration procedure
corresponding to that obtained from the vector meson dominance model but with
multiple scattering effects taken into account.


title:
Precision Calculations of Heavy Boson Production - YFS Monte Carlo
  Approach

abstract:
  In this talk I present the current status of the family of Monte Carlo
programs for four-fermion physics based on the Yennie-Frautschie-Suura
resummation of soft real and virtual photons. I focus on their applications to
LEP2.


title: Equivariant Dimensional Regularization

abstract:
  The calculation of loop amplitudes with parity violation or spin effects
within dimensional regularization needs a consistent definition of gamma5. Also
loop calculations in supersymmetric theories need a consistent definition of
gamma5. In this paper we develop a new formalism, which allows us to define
consistent regularization schemes. We use Grothendieck's K-functor to construct
finite-dimensional vectorspaces of non-integer rank. The rank will play the
role of the ``4-2eps'' in conventional dimensional regularization. We then
define two regularization schemes, one similar to the 't Hooft--Veltman scheme,
the other one as a scheme, where all algebra is performed in four dimensions.
Lorentz invariance is maintained in both cases. However the structure of the
Clifford algebra cannot be preserved. We show that the HV-like scheme and the
four-dimensional scheme correspond to two different deformations of the
Clifford algebra. It is the purpose of this paper to advocate the
four-dimensional scheme for future calculations, since it is easier to use. As
a consistency check we performed explicit one-loop calculations of various
triangle anomalies in both schemes and we found agreement with Bardeen's
results.


title: Precision Calculation of Bhabha Scattering at LEP

abstract:
  For the small-angle Bhabha-scattering process, we consider the error budget
for the calculation of the LEP/SLC luminosity in the Monte Carlo event
generator BHLUMI 4.04, from the standpoint of new calculations of exact results
for the respective O(alpha**2) photonic corrections in the context of the
Yennie-Frautchi-Suura exponentiation. We find that an over-all precision tag
for the currently available program BHLUMI 4.04 can be reduced from 0.11% to
0.061% at LEP1 and from 0.25% to 0.122% at LEP2. For the large-angle Bhabha
process, we present the Monte Carlo program BHWIDE and compare its predictions
with predictions of other Monte Carlo programs as well as semi-analytical
calculations.


title:
Impact of the SUSY Decays on the Search for the MSSM Higgs bosons at the
  LHC

abstract:
  In the context of the Minimal Supersymmetric extension of the Standard Model,
we discuss the impact of the decays of the neutral Higgs bosons into
supersymmetric particles, charginos/neutralinos and sfermions. We show that
these decay modes could be dominant, when they are kinematically accessible,
thus strongly suppressing the branching ratios for the decay channels which are
used to detect the Higgs bosons at hadron colliders. These SUSY decay modes
should therefore not be overlooked in the search for the Higgs particles at the
LHC.


title:
Scanning of hadron cross-section at DAFNE by analysis of initial-state
  radiative events

abstract:
  The initial-state radiative events in electron-positron annihilation into
hadrons at DAFNE have been considered. The coresponding cross-section with the
full first order radiative correction has been calculated. The analytical
calculations take into account the realistic angular acceptance and energy cut
of DAFNE photon detector.


title:
Current tensor with heavy photon for hard pair production by
  longitudinally polarized electron

abstract:
  The electron current tensor for the scattering of heavy photon on
longitudinally polarized electron accompanied with additional hard
electron-positron pair has been considered. The contribution of collinear and
semicollinear kinematics is computed. The full analysis of both, spin-dependent
and spin-independend parts of electron current tensor, is performed. The
obtained result allows to calculate the corresponding contribution into the
second order radiative correction to cross-sections of different processes with
the next-to-leading accuracy.


title:
CP asymmetry for radiative B-meson decay in the supersymmetric standard
  model

abstract:
  We study a rate asymmetry in the inclusive decay $\Bsgamma$, assuming the
supersymmetric standard model based on N=1 supergravity. A complex coefficient
$A$ for scalar-trilinear couplings is the source of CP violation, which is
contained in the mass-squared matrices for squarks. The model parameters are
nontrivially constrained by experimental results for the branching ratio of the
radiative decay and for the electric dipole moments of the neutron and the
electron. The decay rate asymmetry is predicted to be much larger than that by
the standard model in a wide region of the parameter space compatible with the
experiments. Its magnitude can be maximally around 0.1, which will be well
accessible at B factories.


title: Comments on CP, T and CPT Violation in Neutral Kaon Decays

abstract:
  We comment on CP, T and CPT violation in the light of interesting new data
from the CPLEAR and KTeV Collaborations on neutral kaon decay asymmetries.
Other recent data from the CPLEAR experiment, constraining possible violations
of CPT and the $\Delta S = \Delta Q$ rule, exclude the possibility that the
semileptonic-decay asymmetry $A_{T}$ measured by CPLEAR could be solely due to
CPT violation, confirming that their data constitute direct evidence for T
violation. The CP-violating asymmetry in $K_L \to e^-e^+\pi^-\pi^+$ recently
measured by the KTeV Collaboration does not by itself provide direct evidence
for T violation, but we use it to place new bounds on CPT violation.


title: Quarks and Leptons Beyond the Third Generation

abstract:
  The possibility of additional quarks and leptons beyond the three generations
already established is discussed. The make-up of this Report is (I)
Introduction: the motivations for believing that the present litany of
elementary fermions is not complete; (II) Quantum Numbers: possible assignments
for additional fermions; (III) Masses and Mixing Angles: mass limits from
precision electroweak data, vacuum stability and perturbative gauge
unification; empirical constraints on mixing angles; (IV) Lifetimes and Decay
Modes: their dependence on the mass spectrum and mixing angles of the
additional quarks and leptons; the possibility of exceptionally long lifetimes;
(V) Dynamical Symmetry Breaking: the significance of the top quark and other
heavy fermions for alternatives to the elementary Higgs Boson; (VI) CP
Violation: extensions to more generations and how strong CP may be solved by
additional quarks; (VII) Experimental Searches: present status and future
prospects; (VIII) Conclusions.


title:
Application of Pauli-Villars Regularization and Discretized Light-Cone
  Quantization to a (3+1)-Dimensional Model

abstract:
  We apply Pauli-Villars regularization and discrete light-cone quantization to
the nonperturbative solution of a (3+1)-dimensional model field theory. The
matrix eigenvalue problem is solved for the lowest-mass state with use of the
complex symmetric Lanczos algorithm. This permits the calculation of each
Fock-sector wave function, and from these we obtain values for various
quantities, such as average multiplicities and average momenta of constituents,
structure functions, and a form factor slope.


title: A Boltzmann Equation for the QCD Plasma

abstract:
  We present a derivation of a Boltzmann equation for the QCD plasma, starting
from the quantum field equations. The derivation is based on a gauge covariant
gradient expansion which takes consistently into account all possible
dependences on the gauge coupling assumed to be small. We point out a
limitation of the gradient expansion arising when the range of the interactions
becomes comparable with that of the space-time inhomogeneities of the system.
The method is first applied to the case of scalar electrodynamics, and then to
the description of long wavelength colour fluctuations in the QCD plasma. In
the latter case, we recover B\"odeker's effective theory and its recent
reformulation by Arnold, Son and Yaffe. We discuss interesting cancellations
among various collision terms, which occur in the calculation of most transport
coefficients, but not in that of the quasiparticle lifetime, or in that of the
relaxation time of colour excitations.


title: Rapidity veto effects in the NLO BFKL equation

abstract:
  We examine the effect of suppressing the emission of gluons which are close
by in rapidity in the BFKL framework. We show that, after removing the
unphysical collinear logarithms which typically arise in formally higher orders
of the perturbative expansion, the effect of the rapidity veto is greatly
reduced. This is an important result, since it supports the use of multi-Regge
and quasi-multi-Regge kinematics which are implemented in the leading and
next-to-leading order BFKL formalism.


title: The decay Z -> neutrino antineutrino photon in the Standard Model

abstract:
  A complete study of the one-loop induced decay Z -> neutrino antineutrino
photon is presented within the framework of the Standard Model. The advantages
of using a nonlinear gauge are stressed. We have found that the main
contributions come from the electric dipole and the magnetic dipole transitions
of the Z gauge boson and the neutrino, respectively. We obtain a branching
ratio B=7.16E-10, which is about four orders of magnitude smaller than the
bound recentely obtained by the L3 collaboration and thus it leaves open a
window to search for new physics effects in single-photon decays of the Z
boson.


title: Physics opportunities at RHIC and LHC

abstract:
  Nonequilibrium models (three-fluid hydrodynamics, UrQMD, and quark molecular
dynamics) are used to discuss the uniqueness of often proposed experimental
signatures for quark matter formation in relativistic heavy ion collisions from
the SPS via RHIC to LHC. It is demonstrated that these models -- although they
do treat the most interesting early phase of the collisions quite differently
(thermalizing QGP vs. coherent color fields with virtual particles) -- all
yield a reasonable agreement with a large variety of the available heavy ion
data. Hadron/hyperon yields, including $J/\Psi$ meson production/suppression,
strange matter formation, dileptons, and directed flow (bounce-off and
squeeze-out) are investigated. Observations of interesting phenomena in dense
matter are reported. However, we emphasize the need for systematic future
measurements to search for simultaneous irregularities in the excitation
functions of several observables in order to come close to pinning the
properties of hot, dense QCD matter from data. The role of future experiments
with the STAR and ALICE detectors is pointed out.


title: Single Sector Supersymmetry Breaking

abstract:
  We review recent work on realistic models that break supersymmetry
dynamically and give rise to composite quarks and leptons, all in a single
sector. These models have a completely natural suppression of flavor-changing
neutral currents, and the hierarchy of Yukawa couplings is explained by the
dimensionality of composite states. The generic signatures are unification of
scalar masses with different quantum numbers at the compositeness scale, and
lighter gaugino, Higgsino, and third-generation sfermion masses.


title: Analysis of tbW and ttZ couplings from CLEO and LEP/SLC data

abstract:
  We update the constraints on anomalous dimension four $\tbw$ and $\ttz$
couplings by using CLEO $b \ra s \gamma$ and LEP/SLC precision $Z$-pole data.
It is found that the data imposes very stringent bounds on them. Moreover, the
$2 \sigma$ pull from SM predictions of $A_{LR}$(hadrons), $A_b$ and $A_{FB}$(b)
have little chance of being explained by the strongly constrained anomalous
couplings.


title: Electroweak Symmetry Breaking due to Confinement

abstract:
  Within the framework of gauge mediated supersymmetry breaking, we consider an
electroweak symmetry breaking pattern in which there is no conventional $\mu$
term. The pattern is made appealing through realizing it as low energy
effective description of a supersymmetric Yang-Mills theory which is of
confinement. Phenomenological implications are discussed.


title:
Partial widths a_0(980)\to\gamma\gamma, f_0(980)\to\gamma\gamma and
  q\bar q-classification of the lightest scalar mesons

abstract:
  We calculate partial widths for the decays a_0(980)\to\gamma\gamma and
f_0(980)\to\gamma\gamma under the assumption that a_0(980) and f_0(980) are
members of the basic 1^3P_0 q\bar q nonet. The results are in a reasonable
agreement with data thus giving an argument for a q\bar q origin of these
mesons. We also calculate the \gamma\gamma partial widths for the other scalar
mesons, members of the 2^3P_0 q\bar q nonet.


title: How fast do small x structure function rise ? A comparative analysis

abstract:
  We parametrize the small x, singlet component of the proton structure
function F_2 by powers and logarithms of 1/x for discrete values of Q^2 between
0.2 and 2000 GeV^2, and compare these parametrizations by applying the
criterion of minimal $\chi^2$. The obtained values of the fitted parameters may
be used to study the evolution of F_2 in Q^2 and/or in discriminating between
dynamical models. A slowing-down in the increase of F_2 towards highest
available values of Q^2 is revealed. The effect is quantified in terms of the
derivative ${\frac{d\ell n F_2(x,Q^2)}{{d\ell n (1/x)}}}$.


title: Comparing Gluon to Quark Jets with DELPHI

abstract:
  This is a summary of the latest results of the DELPHI Collaboration on the
properties of identified quark and gluon jets. It covers the measurement of the
fragmentation functions of gluons and quarks and their scaling violation
behaviour as well as an analysis of the scale dependence of the multiplicities
in gluon and quark jets. Further, a precision measurement of CA/CF from the
multiplicities in symmetric three jet events is discussed.


title: New Conditions for a Total Neutrino Conversion in a Medium

abstract:
  A new effect of total neutrino conversion is possible when neutrino
propagates through multi-layer medium of nonperiodic constant density layers.
The effect can take place in the oscillations in the Earth of the
Earth-core-crossing solar and atmospheric neutrinos.


title: Strong coupling unification and extra dimensions

abstract:
  We analyze the implications of electroweak and strong coupling unification in
a very general class of models extending the minimal supersymmetric standard
model in $4+p$ dimensions $(p\geq 0)$. In general, electroweak precision data
require the presence of large extra dimensions (low compactification scales,
$M_c$) and/or low unification scale, $M_U$. In particular, the actual
experimental value of the strong coupling at $M_Z$ imposes an upper bound on
the compactification and unification scales. In four dimensional theories
($M_c\simeq M_U$) with canonical hypercharge assignment we find $M_U\lesssim
10^{9}$ GeV. In theories with extra dimensions ($M_c<M_U$) we find $M_c\lesssim
10^7$ GeV, for a supersymmetric spectrum at the TeV scale.


title: Axion Decay of a Photon in an External Electromagnetic Field

abstract:
  An interaction of a pseudoscalar particle with two photons induced by an
external electromagnetic field is used to study the photon decay $\gamma \to
\gamma a$ where a is a pseudoscalar particle associated with the Peccei-Quinn
U(1) symmetry. The field-induced axion emission by photon is analyzed as a
possible source of energy losses by astrophysical objects.


title: Electron and Neutron Electric Dipole Moments in the Constrained MSSM

abstract:
  We analyze the effects of CP-violating phases on the electric dipole moment
(EDM) of electron and neutron in the constrained minimal supersymmetric model.
We find that the phases phi_{\mu} and phi_{A_0} have to be strongly correlated,
in particular for small values of the SUSY mass parameters. We calculate the
neutron EDM in two different models, the Quark-Parton Model and the Chiral
Quark Model. It turns out that the predictions are quite sensitive to the model
used. We show parameter regions in the M_0-M_1/2 plane which are excluded by
considering simultaneously the experimental bounds of both electron and neutron
EDM, assuming specific values for the phases phi_{\mu} and phi_{A_0}.


title: Complete O(N_f alpha^2) Weak Contributions to the Muon Lifetime

abstract:
  The complete O(N_f alpha^2) weak contributions to the muon lifetime, denoted
as Delta r^(2), are calculated in the MS-bar renormalization scheme. These come
from 2-loop Feynman diagrams containing a loop formed by complete generations
of massless fermions. They form an independent, gauge-invariant set of
corrections that, because of the large number of light fermions in the Standard
Model, is expected to make a significant contribution. In the MS-bar
renormalization scheme with mu'= (pi e^gamma)^(1/2) mu = M_Z and for a Higgs
mass, M_H, in the range 100-1000 GeV the contribution varies from -0.55x10^-4
to -1.54x10^-4 for each massless generation of fermions.


title:
The Mass of the Lightest MSSM Higgs Boson: A Compact Analytical
  Expression at the Two-Loop Level

abstract:
  A compact approximation formula for the mass of the lightest neutral CP-even
Higgs boson, m_h, in the Minimal Supersymmetric Standard Model (MSSM) is
derived from the diagrammatic two-loop result for m_h up to O(alpha alpha_s).
By analytically expanding the diagrammatic result the leading logarithmic and
non-logarithmic as well as the dominant subleading contributions are obtained.
The approximation formula is valid for general mixing in the scalar top sector
and arbitrary choices of the parameters in the Higgs sector of the model. Its
quality is analyzed by comparing it with the full diagrammatic result. We find
agreement with the full result better than 2 GeV for most parts of the MSSM
parameter space.


title:
Regge description of spin-spin asymmetry in photon diffractive
  dissociation

abstract:
  We explore the possibility whether the gluon helicity distribution $\Delta
G(x)$ can be extracted from a comparison of experimental data on the
longitudinal spin-spin asymmetry $A_{LL}$ in $\gamma p$ diffractive deep
inelastic scattering with calculations performed within the framework of
perturbative QCD (pQCD). The data could be obtained at the future HERA collider
in scattering of polarized electrons/positrons off polarized protons. In this
paper we look for such kinematical regions where contributions to $A_{LL}$ from
soft processes (reggeon exchanges) are suppressed to guarantee an applicability
of pQCD. It is shown that for the square of the center-of-mass energy
$s_{\gamma p} \geq 10^3 GeV^2$, the hadronic diffractive mass $M_X \leq 10
GeV/c^2$, the momentum transferred to the proton $\Delta_T\leq 0.5 GeV/c$, and
$Q^2\geq4 (GeV/c)^2$ the longitudinal spin-spin asymmetry due to reggeon
exchanges is less than 10^{-4}. This value is presumably lower than the
asymmetry which can be measured with modern experimental technique. This means
that the pQCD prediction can be reliably compared with data in this kinematical
region.


title: Leptogenesis and Yukawa textures

abstract:
  We study a set of textures giving rise to correct masses and mixings of the
charged fermions in the context of leptogenesis. The Dirac neutrino texture
pattern is assumed to be identical with the up quark texture. The heavy
Majonana neutrino mass matrix is obtained by inverting the type-I see-saw
formula and using the neutrino masses and mixings required by the solar and
atmospheric neutrino oscillation experiments as input. After making the
feasibility study of the generated lepton asymmetry via the decay of the heavy
right handed neutrino, we compute the generated baryon asymmetry by numerically
solving the supersymmetric Boltzmann equations. We find for these models that
both the hierarchy of the texture as well as the placement of the texture zeros
are important to the viability of leptogenesis as the source of the observed
baryon asymmetry of the universe.


title: Higgs Compositeness from Top Dynamics and Extra Dimensions

abstract:
  The fundamental Higgs doublet may be replaced in the Standard Model by
certain non-perturbative four-quark interactions, whose effect is to induce a
composite Higgs sector responsible for electroweak symmetry breaking. A simple
composite two-Higgs-doublet model is presented. The four-quark interactions
arise naturally if there are either extra spatial dimensions or larger gauge
symmetries at a multi-TeV scale. Some theoretical and phenomenological
implications of these scenarios are discussed.


title:
L/E-Flatness of the Electron-Like Event Ratio in Super-Kamiokande and a
  Degeneracy in Neutrino Masses

abstract:
  We show that the L/E-flatness of the electron-like event ratio in the
Super-Kamiokande atmospheric neutrino data implies the equality of the
expectation values for the muon and tau neutrino masses. We establish this
result by obtaining a set of three constraints on the neutrino-oscillation
mixing matrix as contained in the indicated flatness. The resulting 3x3
neutrino-oscillation matrix depends only on one angle. A remarkable result that
follows directly from this matrix is the consistency between the mixing angles
observed by LSND and Super-Kamiokande.


title:
Are the reactions $\gamma\gamma\to VV'$ a challenge for the factorized
  Pomeron at high energies?

abstract:
  We would like to point to the strong violation of the putative factorized
Pomeron exchange model in the reactions $\gamma\gamma\to VV'$ in the
high-energy region where this model works fairly well in all other cases.


title: Quark mass anomalous dimension at O(1/N_f^2) in QCD

abstract:
  We compute the d-dimensional critical exponents corresponding to the wave
function and mass renormalization of the quark in QCD in the Landau gauge at a
new order, O(1/N_f^2), in the large N_f expansion. The computations are
simplified by the establishment in d-dimensions of the critical point
equivalence of QCD and the non-abelian Thirring model beyond leading order. The
form of the O(1/N_f^2) coefficients in the MSbar quark mass anomalous dimension
at five loops is deduced and compared with the numerical asymptotic Pade
approximant prediction.


title:
Determination of polarised parton distributions in the nucleon - next to
  leading order QCD analysis

abstract:
  We have made next to leading order QCD fit to the deep inelastic spin
asymmetries on nucleons and we determined polarised quark and gluon densities.
The functional form for such distributions was inspired by the Martin, Roberts
and Stirling fit for unpolarised case. In addition to usually used data points
(averaged over $x$ and $Q^2$) we have also considered the sample containing
points with similar $x$ and different $Q^2$. It seems that splitting of quark
densities into valence and sea contribution is strongly model dependent and
only their sum (i.e., $\Delta u$ and $\Delta d$) can be precisely determined
from the data. Integrated polarised gluon contribution, contrary to some
expectations, is relatively small and the sign of it depends on the fact which
sample of data points is used.


title: Configuration Space Based Recurrence Relations for Sunset-Type Diagrams

abstract:
  We derive recurrence relations for the calculation of multiloop sunset-type
diagrams with large powers of massive propagators. The technique is formulated
in configuration space and exploits the explicit form of the massive propagator
raised to a given power. We write down and evaluate a convenient set of basis
integrals. The method is well suited for a numerical evaluation of this class
of diagrams. We give explicit analytical formulae for the basis integrals in
the asymptotic regime.


title:
Yukawa coupling corrections to stop, sbottom, and stau production in e+
  e- annihilation

abstract:
  We calculate within the MSSM the one-loop Yukawa coupling corrections to the
processes e+ e- \to stops, sbottoms, and staus in order of Yukawa coupling
squared. These corrections are due to the exchange of charginos, neutralinos,
charged and neutral Higgs bosons, and charged and neutral Higgs ghosts. We give
the complete analytical formulae. We also perform a detailed numerical analysis
of the Yukawa coupling corrections, including also the SUSY-QCD corrections. It
turns out that for stop and sbottom production the Yukawa coupling corrections
are typically +/- 10% of the tree-level cross section. For stau production they
are about +/- 5%.


title:
Baryon stopping and hyperon enhancement in the improved dual parton
  model

abstract:
  We present an improved version of the dual parton model which contains a new
realization of the diquark breaking mechanism of baryon stopping. We reproduce
in this way the net baryon yield in nuclear collisions. The model, which also
considers strings originating from diquark-antidiquark pairs in the nucleon
sea, reproduces the observed yields of p and Lambda and their antiparticles and
underestimates cascades by less than 50 %. However, Omega's are underestimated
by a factor five. Agreement with data is restored by final state interaction,
with an averaged cross-section as small as 0.14 mb. Hyperon yields increase
significantly faster than antihyperons, in agreement with experiment.


title: Axion in an External Electromagnetic Field

abstract:
  We investigate the effective interaction of a pseudoscalar particle with two
photons in an external electromagnetic field in the general case of all
external particles being off the mass shell. This interaction is used to study
the radiative decay $a \to \gamma \gamma$ of the axion, a pseudoscalar particle
associated with the Peccei-Quinn symmetry, and the crossing channel of photon
splitting $\gamma \to \gamma a$. It is shown that the external field removes
the suppression associated with the smallness of the axion mass and so leads to
the strong catalysis of these processes. The field-induced axion emission by
photon is analyzed as one more possible source of energy losses by
astrophysical objects.


title: Cosmological Neutrino Condensates

abstract:
  We investigate the possibility that neutrinos form superfluid-type
condensates in background cosmological densities. Such condensates could give
rise to small neutrino masses and splittings, as well as an important
contribution, perhaps, to the cosmological constant. We discuss various
channels in the context of the standard model. Many of these do not support a
condensate, but some mixed-flavor channels do. We also suggest a new
interaction, acting only among neutrinos, that could induce a neutrino Majorana
mass of order 1 eV.


title: Hierarchies without Symmetries from Extra Dimensions

abstract:
  It is commonly thought that small couplings in a low-energy theory, such as
those needed for the fermion mass hierarchy or proton stability, must originate
from symmetries in a high-energy theory. We show that this expectation is
violated in theories where the Standard Model fields are confined to a thick
wall in extra dimensions, with the fermions "stuck" at different points in the
wall. Couplings between them are then suppressed due to the exponentially small
overlaps of their wave functions. This provides a framework for understanding
both the fermion mass hierarchy and proton stability without imposing
symmetries, but rather in terms of higher dimensional geography. A model
independent prediction of this scenario is non-universal couplings of the
Standard Model fermions to the ``Kaluza-Klein'' excitations of the gauge
fields. This allows a measurement of the fermion locations in the extra
dimensions at the LHC or NLC if the wall thickness is close to the TeV scale.


title:
Radiative decay of the lightest neutralino in an R-parity violating
  supersymmetric theory

abstract:
  In an R-parity violating supersymmetric scenario, the lightest neutralino
$\tilde \chi^0_1$ is no longer a stable particle. We calculate the branching
ratio for the decay mode $\tilde \chi^0_1 \longrightarrow \nu \gamma$ which
occurs at the one-loop level. Taking into account bilinear as well as trilinear
lepton number violating interactions as the sources of R-parity violation, we
make a detailed scan of the parameter space, both with and without gaugino mass
unification and including the constraints on the neutrino sector from the
recent Superkamiokande results. This study enables one to suggest interesting
experimental signals distinguishing between the two types of R-parity breaking,
and also to ascertain whether such radiative decays can give rise to collider
signals of the type $\gamma \gamma$ + $\not {\rm E}$ from pair-produced
neutralinos.


title: Resonant Slepton Production

abstract:
  We consider the production of resonant sleptons via R-parity Violation
followed by gauge decays to a charged lepton and a neutralino which then decays
via R-parity Violation. This gives a signature of two like-sign charged
leptons. We find a background at run II of 0.14 +/- 0.13 events with an
integrated luminosity of 2 fb^-1. This enables us to probe R-parity Violating
couplings of 2.10^-3 for slepton mass of 100 GeV and up to slepton masses of
300 GeV for R-parity Violating couplings of 10^-2.


title:
The Linear Sigma Model at Work: Succesful Postdictions for Pion
  Scattering

abstract:
  We enforce chiral Ward identities on the vertices of the linear sigma model
to take into account the width of the scalar sigma, considered as a true
physical resonance. We consider pion scattering at very low energies and, from
a fit to the measured phase shifts in the various angular momentum and isospin
channels, conclude a mass for the sigma of 600+200-100 MeV. Its width turns out
to be of the same size.


title:
Perturbative QCD Correction to the Light-Cone Sum Rule for the $B^*B\pi
  $ and $D^*D\pi$ Couplings

abstract:
  The $B^*B\pi$ and $D^*D\pi$ couplings have previously been derived from a QCD
light-cone sum rule in leading order. Here, we describe the calculation of the
$O(\alpha_s)$ correction to the twist 2 term of this sum rule. The result is
used for a first next-to-leading order analysis. We obtain $g_{B^*B\pi}= 22\pm
7$ and $g_{D^*D\pi}=10.5\pm 3$, where the error indicates the remaining
theoretical uncertainty.


title: SN1987A Constraints on Large Compact Dimensions

abstract:
  Recently there has been a lot of interest in models in which gravity becomes
strong at the TeV scale. The observed weakness of gravitational interactions is
then explained by the existence of extra compact dimensions of space, which are
accessible to gravity but not to Standard Model particles. In this letter we
consider graviton emission into these extra dimensions from a hot supernova
core. The phenomenology of SN1987A places strong constraints on this energy
loss mechanism, allowing us to derive a bound on the fundamental Planck scale.
For the case of two extra dimensions we obtain a very strong bound of M > 50
TeV, which corresponds to a radius R < 0.3 microns. While there are a lot of
sources of uncertainty associated with this bound, we find that pushing it down
to the few-TeV range, which could in principle be probed by ground-based
experiments, is disfavored. For three or more extra dimensions the SN1987A
constraints do not exclude a TeV gravitational scale.


title:
Phenomenological Constraints on Supersymmetric Models with an Anomalous
  U(1) Flavor Symmetry

abstract:
  We investigate supersymmetric models in which an anomalous $U(1)_{X}$
symmetry explains the Yukawa hierarchy, and the related $D_{X}$-term plays a
role in supersymmetry breaking. We use a bottom-up approach to model building.
Phenomenological viability leads to a scenario with degenerate squark and
slepton spectra and with heavy gauginos. Features of a K\"ahler potential that
allows for such a scenario are described.


title:
Enhancing Mechanisms of Neutrino Transitions in a Medium of Nonperiodic
  Constant - Density Layers and in the Earth

abstract:
  The extrema of the probabilities of the transitions $\nu_{\mu} (\nu_e) \to
\nu_e (\nu_{\mu;\tau})$, $\nu_{2} \to \nu_e$, etc. of neutrinos passing through
a medium consisting of i) two layers of different constant densities or ii)
three layers of constant density, of which the first and the third are
identical but differ in density from the second (e.g., mantle-core-mantle in
the Earth), are analyzed. We show that in addition to the MSW and neutrino
oscillation length resonance (NOLR) local maxima previously discussed, there
exist new resonance-like absolute maxima of interference nature. The latter
correspond to a new effect of total neutrino conversion. The conditions for
existence of the new maxima are fulfilled, in particular, for the
Earth-core-crossing solar and atmospheric neutrinos. We prove that the NOLR and
the new resonance-like enhancement are caused by a maximal constructive
interference between the amplitudes of the neutrino transitions in the
different density layers. The strong resonance-like enhancement of the
transitions in the Earth of the Earth-core-crossing solar and atmospheric
neutrinos is due to the new effect of total neutrino conversion.


title:
Examining the cancellation mechanism of neutron EDM in a model with
  dilaton-dominated susy breaking

abstract:
  We examine the cancellation mechanism between the different contributions to
the electric dipole moment of the neutron in a model with dilaton-dominated
SUSY breaking. We find these accidental cancellations occur at few points in
parameter space. For a wide region of this space we must constrain the phase of
$\mu$ to be of order $10^{-1}$ and have the phases of $A$ and $\mu$ strongly
correlated in order to have small neutron EDM. Moreover, we consider the
indirect CP violation parameter $\epsilon$ in this region where the electric
dipole moment is less than the experimental limit and find that we can generate
$\epsilon$ of order $10^{-6}$.


title:
On the complete next-to-leading order pQCD prediction for the pion form
  factor

abstract:
  We comment on the results of a complete leading-twist next-to-leading order
QCD analysis of the spacelike pion electromagnetic form factor at
large-momentum transfer Q. For the asymptotic distribution amplitude, we have
examined the sensitivity of the predictions to the choice of the
renormalization scale. The results show that reliable perturbative predictions
for the pion electromagnetic form factor can already be made at a momentum
transfer Q below 10 GeV.


title: The role of K^*_0(1430) in D->PK and \tau->KP\nu_\tau decays

abstract:
  We consider the scalar form factor in the weak current matrix element <P K|
j_\mu |0>, P =\pi,\eta,\eta'. It obtains the contributions from the scalar
meson resonance K^*_0(1430) and from the scalar projection of the vector meson
K^*(892) resonance. We analyze decay amplitudes of the Cabibbo suppressed
decays D->K P, P =\pi,\eta,\eta' using the factorization approach. The form
factors of the relevant matrix elements are described by assuming the dominance
of nearby resonances. The annihilation contribution in these decays arises from
the matrix element <P K| j_\mu |0>. All the required parameters are
experimentally known except the scalar meson K^*_0(1430) decay constant. We fit
the decay amplitudes and we find that final state interaction improves the
agreement with the experimental data. Then we extract bounds on scalar form
factor parameters and compare them with the experimental data obtained in the
analyses of K->\pi e\nu_e and K->\pi\mu\nu_\mu. The same scalar form factor is
present in the \tau-> K P \nu_\tau decay, with P =\pi,\eta,\eta'. Using the
obtained bounds we investigate the significance of the scalar meson form factor
in the \tau-> K P \nu_\tau, P = \pi, \eta, \eta' decay rates and spectra. We
find that the K^*_0(1430) scalar meson dominates in the \tau-> K \eta'\nu_\tau
decay spectrum.


title: Unique Mass Texture for Quarks and Leptons

abstract:
  Texture specific quark mass matrices which are hermitian and hierarchical are
examined in detail . In the case of texture 6 zeros matrices, out of sixteen
possibilities examined by us, none is able to fit the low energy data (LED),
for example, $V_{us} = 0.2196 \pm 0.0023$, $V_{cb} = 0.0395 \pm 0.0017$,
$\frac{V_{ub}}{V_{cb}} = 0.08 \pm 0.02$, $V_{td}$ lies in the range $0.004 -
0.013$ (PDG). Similarly none of the 32 texture 5 zeros mass matrices considered
is able to reproduce LED. In particular, the latest data from LEP regarding
$|V_{ub}|/|V_{cb}|(=0.093\pm0.016)$ rules out all of them. In the texture 4
zeros case, we find that there is a unique texture structure for $U$ and $D$
mass matrices which is able to fit the data.


title:
Initial-Boundary Value Problem and Stability of Solutions for String
  Baryon Model "Triangle"

abstract:
  For the string baryon model "triangle" the initial-boundary value problem is
stated and solved in general. This problem implies defining a classical motion
of the system on the base of given initial position and initial velocities of
string points. The presented solution reduces the initial-boundary value
problem for the considered model to the system of ordinary differential
equations that can be integrated numerically in general. Using this approach we
ascertain the stability of the rotational motions (flat uniform rotations) for
the "triangle" string configuration.


title:
Sensitivities of one-prong tau branching fractions to tau neutrino mass,
  mixing, and anomalous charged current couplings

abstract:
  We analyse the sensitivities of exclusive one-prong tau branching fractions
to: the tau neutrino mass; its mixing with a fourth generation neutrino; the
weak charged current magnetic and electric dipole moments of the tau; and the
Michel parameter $\eta$. Quantitative constraints are derived from current
experimental data and the future constraints derivable from tau-charm factory
measurements are estimated. The anomalous coupling constraints are used to
constrain the tau compositeness scale and the allowed parameter space for Higgs
doublet models.


title: The Unitary Mechanism of Infrared Freezing in QCD with massive gluons

abstract:
  A "natural" model for the QCD invariant (running) coupling, free of the IR
singularity, is proposed. It is based upon the hypothesis of finite gluon mass
$ m_{gl}$ existence and, technically, uses an accurate treating of threshold
behavior of Feynman diagram contribution. The model correlates with the
unitarity condition.
  Quantitative estimate, performed in the one-loop approximation yields a
reasonable lower bound for this mass $m_{gl} > 150$ MeV and a smooth IR
freezing at the level $\alpha_s(Q^2)\lesssim 1$.