title:
Dynamical Scenarios for Anomalous Interactions involving t, b quarks and
  bosons

abstract:
  In the present paper we explore various dynamical scenarios for New Physics
(NP) which could be generated by very heavy particles and observed in the form
of non-standard "low energy" interactions affecting the scalar sector, the
gauge bosons and the quarks of the third family. Such interactions have been
previously expressed in terms of 48 CP-conserving gauge invariant operators. We
show that each scenario is characterized by a specific subset of such
operators. Thus, if some traces of NP are ever found in the experimental data,
then the comparison with the predictions of the various scenarios, should be
able to guide the search towards the underlying dynamics generating it.


title:
Exclusive $\eta_c$ photo- and electroproduction at HERA as a possible
  probe of the odderon singularity in QCD

abstract:
  Theory and phenomenology of the eta_c photo- and electroproduction is
developed from the point of view of probing the odderon singularity in QCD
which corresponds to the three gluon exchange mechanism. This mechanism leads
to the cross-sections which are independent of W^2 for the exchange of three
non-interacting gluons or exhibit increase with increasing W^2 (or 1/x) for the
odderon intercept above unity. The \eta_c electroproduction in the three gluon
exchange mechanism is shown to be entirely controlled by the transversely
polarised virtual photons. The magnitude of the eta_c photoproduction
cross-section is estimated to be around 11-45pb. The t-dependence of the
differential cross-section is also discussed.


title:
Spin and velocity dependent corrections to the interquark potential and
  quarkonia spectra from lattice qcd

abstract:
  We present results on (order v^2) QCD interquark potentials from SU(3)
lattice simulations on volumes of up to 32^4 lattice sites at beta = 6.2 and
beta = 6.0. Preliminary results on quarkonia spectra as obtained from these
potentials are presented.


title: Neutral Heavy Leptons and Electroweak Baryogenesis

abstract:
  We investigate the possibility that baryogenesis occurs during the weak phase
transition in a minimal extension of the Standard Model which contains extra
neutral leptons and conserves total lepton number. The necessary CP-violating
phases appear in the leptonic Yukawa couplings. We compute the CP-asymmetries
in both the neutral and the charged lepton fluxes reflected on the bubble wall.
Using present experimental bounds on the mixing angles and Standard Model
estimates for the parameters related to the scalar potential, we conclude that
it seems unlikely to produce the observed baryon to entropy ratio within this
type of models. We comment on the possibility that the constraints on the
mixings might be naturally relaxed due to small finite temperature effects.


title: Formation of DCCs with the linear sigma model

abstract:
  A simple approximate treatment of statistical equilibrium is developed within
the linear sigma sigma model by means of the Hartree factorization technique,
providing a simple means for sampling initial configurations of the chiral
field. These are then subjected to pseudo-expansions and their non-equilibrium
relaxation towards the normal vacuum is studied.


title:
Gauge and Yukawa Unification in Models with Gauge-Mediated Supersymmetry
  Breaking

abstract:
  We examine gauge and Yukawa coupling unification in models with
gauge-mediated supersymmetry breaking. We work consistently to two-loop order,
and include all weak, messenger and unification-scale threshold corrections. We
find that successful unification requires unification-scale threshold
corrections that are in conflict with the minimal SU(5) model, but are
consistent with the modified missing doublet SU(5) model for small tan beta,
and large tan beta with mu>0.


title:
Q^2-evolution of chiral-odd twist-3 distributions h_L(x,Q^2) and e(x,
  Q^2) in the large N_c limit

abstract:
  We prove that the twist-3 chiral-odd parton distributions obey simple GLAP
evolution equations in the limit $N_c\to\infty$ and give analytic formulae for
the corresponding anomalous dimensions. The results are valid to O(1/N_{c}^2)
accuracy and will be useful in confronting with future experiments.


title: Gravitational Effects on the Neutrino Oscillation

abstract:
  The propagation of neutrinos in a gravitational field is studied. A method of
calculating a covariant quantum-mechanical phase in a curved space-time is
presented. The result is used to calculate gravitational effects on the
neutrino oscillation in the presence of a gravitational field. We restrict our
discussion to the case of the Schwartzschild metric. Specifically, the cases of
the radial propagation and the non-radial propagation are considered. A
possible application to gravitational lensing of neutrinos is also suggested.


title:
PROSPINO: A Program for the Production of Supersymmetric Particles in
  Next-to-leading Order QCD

abstract:
  A Fortran-program for the production cross-sections of squarks and gluinos at
hadron colliders is described. It includes full next-to-leading order SUSY-QCD
corrections to all possible final states ($\squark\squarkbar, \gluino\gluino,
\squark\gluino, \squark\squark$). The program allows to calculate total
cross-sections as well as differential distributions in the transverse momentum
p_t and the rapidity y of one of the outgoing particles. In addition cuts in
p_t and y can easily be implemented.


title:
Neutron spin-dependent structure function, Bjorken sum rule, and first
  evidence for singlet contribution at low x

abstract:
  We perform the isospin decomposition of proton and neutron SLAC data in the
region $0.01 \leq x \leq 0.1$. The isovector part is well described by a power
behaviour $x^{\alpha}$, where $\alpha$ leads to the validity of Bjorken sum
rule and it is consistent with the power extracted from all previous data using
NLO evolution. The isoscalar part behaviour may be interpreted as a partial
cancellation between a positive non-singlet contribution and a singlet one
strongly negative.


title:
How to calibrate the polarization of a high energy proton beam? A
  theoretical prospect

abstract:
  In view of the realistic possibility for operating high-energy polarized
proton beams in future collider machines, it is highly desirable to propose for
such beams, an absolute calibration allowing to measure accurately their degree
of polarization. We consider more specifically one practical method based on pp
elastic scattering near the forward direction and we discuss its limitations.


title: pi-pi S-Wave Interaction and 0++ Particles

abstract:
  From a re-analysis of pi+ pi- -> pi+ pi- and pi+ pi- -> K K data, we found
for pi-pi S-wave interaction below 2 GeV, sigma(400), f0(980), f0(1500) and
f0(1780) clearly show up. f0(1370) can be included with a very small branching
ratio to pi-pi. f0(1300) and f0(1590) are not real resonances and are due to
interference effects of above resonances. The sigma(400) with a width about 700
MeV is mainly produced by t-channel exchange force.


title: On the Theoretical Understanding of Inclusive $\Lambda_b$ Decays

abstract:
  I discuss a QCD sum rule determination of the four-quark operator matrix
elements contributing to the $\Lambda_b$ inclusive decay rates at the order
$m_b^{-3}$. The results suggest that $1/m_b^3$ corrections are not responsible
of the observed difference between the lifetimes of $\Lambda_b$ and $B_d$.


title:
The supersymmetric prediction for the muon transverse polarization in
  the $K^+ \leftarrow \pi^0 \mu^+ \nu_\mu$ decay

abstract:
  The muon transverse polarization in the $K^+ \leftarrow \pi^0 \mu^+ \nu_\mu$
decay will be measured at the $10^{-4}$ level in forthcoming experiments. We
compare the phenomenological perspectives with the theoretical predictions in
supersymmetric extensions of the standard model. In the minimal extension,
CP-violating phases lead to a non-zero transverse polarization, that however is
too small to account for a positive experimental signal. The problems that one
encounters when departing from minimal assumptions are discussed. An observable
effect is possible if the hypothesis of R-parity conservation is relaxed, but
only at the price of assuming a very special pattern for the R-parity breaking
couplings.


title: Okubo-Zweig-Iizuka Rule Violation and Possible Explanations

abstract:
  Violations of the Okubo-Zweig-Iizuka (OZI) rule in $s\bar s <-> n\bar n = 1/2
(u\bar u + d\bar d)$ mixing and $\phi$ production from nucleon-antinucleon
annihilation are reviewed. Possible explanations are examined. We conclude that
the two-step hadronic loops can explain these OZI violations naturally with
proper consideration of cancellations between loops. No conclusive evidence
exists for glueball states, $s\bar sn\bar n$ four quark states, instanton
effects, and strange quarks in nucleon.


title: Status of precision tests of the Standard Model

abstract: The status of precision tests of the Standard Model is reviewed.


title: Top Quark Theory

abstract:
  I review recent theoretical work on top-quark physics within the standard
model, beyond the standard model, and at the Planck scale.


title:
Computing Techniques for Two-Loop Corrections to Anomalous Magnetic
  Moments of Leptons

abstract:
  Two-loop electroweak corrections to the electron, muon, and tau lepton
anomalous magnetic moments have been computed recently. Effects of hadronic
contributions to the photon propagator in two-loop QED corrections have also
been reanalysed. The common technique used in both calculations was asymptotic
expansion of Feynman diagrams in the ratio of lepton mass to some heavy mass
scale. In this talk we present some details of this method paying particular
attention to the expansion of multi-scale diagrams.


title: Calculating hadronic properties in strong QCD

abstract:
  This talk, given at the Second Workshop on ELFE Physics, St Malo, France,
September 1996, presents a brief review of the progress that has been made in
calculating the properties of hadrons in strong QCD.


title: Naturalness constraints on gauge-mediated supersymmetry breaking models

abstract:
  The question of naturalness is addressed in the context of gauge-mediated
supersymmetry breaking models. Requiring that $M_Z$ arises naturally imposes
upper limits on the right-handed selectron mass in these models that are
stronger than in the Minimal Supersymmetric Standard Model and are interesting
from the point of view of searches at the current and future colliders.


title:
Anomalous t-c-g coupling: The connection between single top production
  and top decay

abstract:
  Continuing earlier work, we examine the constraint on an anomalous t-c-g
coupling from top quark decay. We find that from current CDF measurements of
the branching ratio $t \rightarrow W b$, the minimum scale at which new physics
can strongly modify the t-c-g coupling is \Ltcg $\geq$ about 950 GeV. At the
upgraded Tevatron, single top production can constrain \Ltcg $\geq$ 4.5 TeV.
The connection between t-c production and the decay $t \rightarrow c g$ is
examined, showing how constraints on one lead to a constraint on the other.


title: Tau Decays Beyond the Standard Model

abstract:
  In a recent paper, 8 semileptonic parameters were defined to specify the most
general Lorentz-invariant spin correlation functions for 2-body tau decays.
These parameters can be used to search for anomalous longitudinal-versus
transverse polarized-partial widths, for non-CKM-type leptonic CP violation,
and for leptonic T violation. They can also be used to bound the effective-mass
scales ``Lambda" for new physics arising from additional Lorentz structures,
e.g. from lepton compositeness, tau weak magnetism, weak electricity, or
second-class currents. It is emphasized that (i) for these tests ``different
modes have different merits" and that (ii) the parameters can be measured
either by using spin-correlation techniques without polarized beams, or with
longitudinally polarized beams.


title: Polarized Parton Distributions: Theory and Experiments

abstract:
  I review the constituent contributions to the spin of the proton extracted
from recent data at CERN, SLAC and DESY. The valence, sea quark and antiquark
spin-weighted distributions are determined separately. The data appear to imply
a small to moderate polarized gluon distribution, so that the anomaly term is
not significant in determining these contributions. We have analyzed the
consistency of the results obtained from various sets of data and the Bjorken
Sum Rule. All data are consistent with the sum rule, but they differ in the
contribution of the strange sea to proton spin. This and the remaining
uncertainty in the polarized gluon distribution pose unanswered questions about
hadronic spin. Further experiments are suggested which can extract information
about the polarized gluon and sea to address these questions.


title:
Non-Universal Correction to $Z \to b {\overline b}$ and Single Top Quark
  Production at Tevatron

abstract:
  New physics associated with the heavy top quark can affect top quark
production and the partial decay width of $Z \rightarrow b \bar b$. In this
paper, we examine the correlated effects of possible new physics on ${R_b}$
measured at LEP I and the single top quark production rate at Tevatron by using
an effective lagrangian technique. We point out that certain operators in the
effective lagrangian, constrained by the measured value of $R_b$, can lead to
significant and potentially observable effects in single top production.


title: Standard Higgs Boson Searches at LEP 2

abstract:
  For the first time at LEP most of the events will have four fermions in the
finals state and we have the unique opportunity of testing a complete
calculation with the experimental data, well beyond the usual approximation of
computing production cross section times branching ratios of Higgs into decay
products. Calculation of the total cross sections and of different kinds of
differential distributions at the partonic level are made available to access
the widest information for choosing cuts, for discussing the physics of a
standard Higgs boson with a mass around 90 GeV where the Higgs and the Z signal
become degenerate and for a comprehensive analysis of the various background
components.


title:
GALUGA, a Monte Carlo program for two-photon processes in e+e-
  collisions

abstract:
  A Monte Carlo program is presented for the computation of the most general
cross section for two-photon production in e+e- collisions at fixed two-photon
invariant mass W. Functions implemented for the five gamma* gamma* structure
functions include three models of the total hadronic cross section and the
lepton-pair production cross section. Prospects of a structure-function
determination through a study of the azimuthal dependence between the two
scattering planes are outlined. All dependences on the electron mass and the
photon virtualities Q_i^2 are fully kept. Special emphasis is put on a
numerically stable evaluation of all variables over the full Q_i^2 range from
Q_{i\min}^2 \sim m_e^2 (W/\sqrt{s})^4 \ll m_e^2 up to Q_{i\max}^2 \sim s. A
comparison is made with an existing Monte Carlo program for lepton-pair
production and an equivalent-photon approximation for hadronic cross sections.


title:
Gluon-mass effects in quarkonia decays, $e^+e^-$ annihilation and the
  scalar glueball current

abstract:
  In this paper we continue previous efforts in the literature to determine
phenomenological values for the gluon mass by confronting theoretical results
obtained in a theory of massive gluons with experimental values or results
directly referring to the nontrivial structure of the Yang-Mills vacuum, e.g.
to the presence of the gluon condensate. The decays of heavy quarkonia into 3
gluons and 2 gluons + photon are considered in detail as well as the
correlators of the electromagnetic current and the scalar glueball current.
Based on the analysis for the latter quantities a value for the gluon mass in
the range of 500-600 MeV is estimated from the standard SVZ-value of the gluon
condensate.


title: Phenomenology of supersymmetric models with a singlet

abstract:
  The supersymmetric extension of the standard model with an additional gauge
singlet is analysed in detail in the light of the recent experimental bounds on
supersymmetric particles. The useful part of the parameter space and the
particle spectrum are displayed. We find that once the recent bounds on the
chargino mass are imposed, all other new particles practically satisfy the
present experimental limits. Special attention is given to particles to be
searched for in the future experiments. The singlet fields tend to decouple and
give rise to an effective MSSM, enlarging the validity of many phenomenological
analyses based in the minimal field content. However, in some ranges of the
parameters the singlino is the lightest neutralino, which modifies the
signature for susy particles. Simple analytical approximations are developed
that qualitatively explain the numerical results.


title: Spin asymmetries of the proton-proton elastic scattering at HERA-N

abstract:
  The spin correlation parameters, polarization - $A_{N}$ and double spin
correlation parameters - $A_{NN}$, are calculated in the framework of dynamical
model (GKS) of the hadron-hadron interection in the whole region of small
angles and for energy HERA-N $\sqrt{s}=40 GeV$. It is shown that the
measurements of such spin effects at small trunsfer momenta, in the region of
the dip structure and at $t=-4 GeV^{2}$ have to give significant values of such
spin correlation parameters.


title: Aspects of chiral pion-nucleon physics

abstract:
  The next-to-leading order chiral pion-nucleon Lagrangian contains seven
finite low-energy constants. Two can be fixed from the nucleon anomalous
magnetic moments and another one from the quark mass contribution to the
neutron-proton mass splitting. We find a set of nine observables, which to one
loop order do only depend on the remaining four dimension two couplings. These
are then determined from a best fit. We also show that their values can be
understood in terms of resonance exchange related to $\Delta$ excitation as
well as vector and scalar meson exchange. In particular, we discuss the role of
the fictitious scalar-isoscalar meson. We also investigate the chiral expansion
of the two P-wave scattering volumes $P_1^-$ and $P_2^+$ as well as the
isovector S-wave effective range parameter $b^-$. The one-loop calculation is
in good agreement with the data. The difference $P_1^- - P_2^+$ signals chiral
loop effects in the $\pi N$ P-waves. The calculated D- and F-wave threshold
parameters compare well with the empirical values.


title: Current Issues in the Phenomenology of Particle Physics

abstract:
  The present status of the Standard Model and its experimental tests are
reviewed, including indications on the likely mass of the Higgs boson. Also
discussed are the motivations for supersymmetry and grand unification, searches
for sparticles at LEP, neutrino oscillations, and the prospects for physics at
the LHC.


title: CP Violation: The Future of B Physics

abstract:
  The subject of CP violation in B decays is reviewed in the Standard Model
(SM) and beyond the SM. The present explanation of CP violation in terms of
phases in the Cabibbo-Kobayashi-Maskawa (CKM) matrix can be tested through a
variety of CP asymmtries in neutral and charged B decays. SM constraints on the
CKM phases are violated by new mechanisms of CP nonconservation beyond CKM.
Different mechanisms can be distinguished by combining measurements of CP
asymmetries with rate measurements of so-called penguin B decays.


title:
On the calculation of hadron form factors from Euclidean Dyson-Schwinger
  equations

abstract:
  We apply Euclidean time methods to phenomenological Dyson-Schwinger models of
hadrons. By performing a Fourier transform of the momentum space correlation
function to Euclidean time and by taking the large Euclidean time limit, we
project onto the lightest on-mass-shell hadron for given quantum numbers. The
procedure, which actually resembles lattice gauge theory methods, allows the
extraction of moments of structure functions, moments of light-cone wave
functions and form factors without `ad hoc' extrapolations to the on-mass-shell
points. We demonstrate the practicality of the procedure with the example of
the pion form factor.


title:
Analysis of the renormalization scheme ambiguities in the QCD
  corrections to hadronic decays of the tau lepton

abstract:
  The QCD corrections to the R_{\tau}^{12} moment of the invariant mass
distribution in hadronic decays of the tau lepton are discussed. The
next-to-next-to-leading order prediction is shown to be stable with respect to
change of the renormalization scheme, provided that the contour integral
expression is used. The optimized predictions are obtained using the principle
of minimal sensitivity to select the preferred renormalization scheme. The
optimized predictions for R_{\tau}^{12} and R_{\tau} are used in a simplified
fit to the experimental data to determine the strong coupling constant and the
parameter characterizing the nonperturbative contribution.


title: (No) Color in QCD: Charmonium, Charm and Rapidity Gaps

abstract:
  The reason why some data on the production of $\psi$- and $\Upsilon$-states
disagree with QCD predictions, occasionally by well over one order of
magnitude, is that the traditional method for performing the perturbative
calculation of the cross section is simply wrong. The key mistake is to require
that the heavy quark pair forms a color singlet at short distances, given that
there is an infinite time for soft gluons to readjust the color of the $c \bar
c$ pair before it appears as an asymptotic $\psi$ or, alternatively, $D \bar D$
state. We suspect that the same mistake is made in the description of rapidity
gaps, i.e.\ the production of a color-neutral quark-antiquark pair, in terms of
the exchange of a color neutral gluon pair. The $\psi$ is after all a color
neutral $c \bar c$ pair and we will show that it is produced by the same
dynamics as $D \bar D$ pairs; its color happens to be bleached by soft
final-state interactions. This approach to color is suggestive of the
unorthodox prescription for the production of rapidity gaps in deep inelastic
scattering, proposed by Buchm\"uller and Hebecker. When applied to the
formation of gaps between a pair of high transverse momentum jets in hadron
collisions, the soft color approach suggests a formation rate of gaps in
gluon-gluon subprocesses which is similar or smaller than in quark-quark
induced events. Formation of gaps should increase when increasing transverse
momentum or lowering energy, in contrast with 2-gluon exchange Pomeron models.


title: Theoretical Aspects of the Heavy Quark Expansion

abstract:
  I give a brief outline of the theoretical framework for the modern treatment
of the strong interaction effects in heavy quark decays, based on first
principles of QCD. This model-independent approach is required to meet the
precision of current and future experiments. Applications to a few problems of
particular practical interest are reviewed, including the precise determination
of V_{cb} and V_{ub}. I emphasize the peculiarities of simultaneously
accounting for the perturbative and power-suppressed effects necessary for
accurate predictions.


title: Heavy-baryon chiral perturbation theory and reparametrization invariance

abstract:
  We examine the constraints imposed by reparametrization invariance on
heavy-baryon chiral perturbation theory (HBChPT). We study the case of 3
flavors and consider both the strong and weak ($|\Delta S| =1$) interaction
sector. Some of the parameters in the HBChPT Lagrangian are fixed as a
consequence of reparametrization invariance. We discuss the consequences for
the calculation of hyperon weak radiative decays in HBChPT.


title: CP violation with two generations and pseudoscalar mesons revisited

abstract:
  After developing in ref.[1] a SU(2)left x U(1) gauge theory for J=0 mesons, I
show in the case of two generations that: - the electroweak mass eigenstates
differ, especially in the K and D sector, from what they are assumed to be on
the basis of a classification by the SU(4) group of flavour; - a new mechanism
for CP violation springs out, different from that of the standard model for
quarks which requires at least three generations, and I construct a SU(2)left x
U(1) gauge invariant Lagrangian which is not invariant by CP.


title: Flavor asymmetry $\bar u-\bar d$ in the nucleon

abstract:
  We give a brief summary of the Gottfried sum rule and a flavor asymmetric
distribution $\bar u-\bar d$ in the nucleon. First, experimental history of the
sum-rule studies is discussed. Second, future prospects for studying the
asymmetry at Fermilab and RHIC are discussed. We also comment on possible
nuclear modification.


title:
Non-linear Sigma Model Solutions for the Disoriented Chiral Condensate
  at O(p^4)

abstract:
  Boost-invariant (1+1) dimensional solutions for the Disoriented Chiral
Condensate (DCC) are obtained numerically, in the context of the $SU(2)_L
\otimes SU(2)_R$ non-linear sigma model at O(p^4) in the momentum expansion. We
ignore the mass terms in the Lagrangian, as we are mainly interested in the
behavior of the solutions for small values of proper time $\tau$. The solutions
obtained at O(p^4) are matched to those of O(p^2) at a late proper time $\tau
\gg 1/m_\pi$, where $m_\pi = 140$ MeV is the mass of the pion. We find that at
O(p^4) the solutions for the DCC do not have singular behavior at early proper
times $\tau \ll 1/m_\pi$. The solutions indicate that for $\tau \lsim
(0.5-0.8)$ fm the O(p^4) corrections become important. We take the sizes of the
field derivatives to be indicators of the validity of the momentum expansion.
Thus, we deduce that the O(p^4) solutions can be used to represent the
qualitative behavior of the DCC down to proper times of about 0.2 fm. Since
below $\sim 0.2$ fm the formalism is not reliable, we conclude that the
inclusion of higher order terms beyond O(p^4) is not needed to extend the
validity of the solutions to earlier proper times.


title: J/psi Production at the LHC

abstract:
  We firstly examine hadroproduction of prompt J/psi's at the Fermilab Tevatron
in a Monte Carlo Framework by means of the event generator PYTHIA 5.7 in which
those colour-octet matrix elements processes relevant for charmonium production
have been implemented accordingly. We find that colour-octet matrix elements
presented in literature from p-pbar collider data are systematically
overestimated due to overlooking of the effective primordial transverse
momentum of partons (i.e. including higher-order QCD effects). We estimate the
size of these effects using different parton distribution functions. Finally,
after normalization to Tevatron data, we extrapolate up to LHC energies making
a prediction on the expected pt differential cross-section for charmonium.


title: Topcolor Models and Scalar Spectrum

abstract:
  We review the motivation and main aspects of Topcolor models with emphasis on
the spectrum of relatively light scalars and pseudo-scalars.


title: Solution of the strong CP problem

abstract:
  I put forward an SU(2)_L x SU(2)_R x U(1) model in which spontaneously broken
parity symmetry makes it that strong CP violation only arises at three-loop
level. All leptons and up-type quarks are in doublets either of SU(2)_L or of
SU(2)_R, but there are singlet down-type quarks. A bi-doublet of scalars is
introduced which has only one component with non-vanishing expectation value,
thereby avoiding W_L-W_R mixing. The scalar potential is such that
scalar-pseudoscalar mixing does not occur either.


title: Perturbative QCD and Tau Decay

abstract:
  Sufficiently inclusive observables in the decay of the tau lepton can be
calculated using the methods of perturbative QCD. These include the asymmetry
parameter $A_\tau$ that determines that angular distribution of the total
hadron momentum in the decay of a polarized tau. It should be possible to
measure $A_\tau$ accurately using existing data from LEP. Reliable estimates of
theoretical errors are essential in order to determine whether a given
observable is sufficiently inclusive to be calculated using perturbative
methods. The theoretical uncertainties due to higher orders in $\alpha_s$ can
be estimated using recent calculations to all orders in the large-$(33-2N_f)$
limit. These estimates indicate that tau decay data can be used to determine
$\alpha_s(M_Z)$ to a precision of 2% or better.


title: Soft CP breaking and the strong-CP problem

abstract:
  I put forward a model with vectorlike isosinglet quarks in which soft
breaking of CP leads to strong CP violation only arising at two-loop level.


title: Rapidity gaps in minijets production at Tevatron energies

abstract:
  Multiparton interactions modify the high energy hadronic cross section to
produce minijets with a rapidity gap in the distribution of secondaries. At
Tevatron energy the correction to the single scattering term is large for
transverse momenta smaller than 6 GeV.


title: Rare processes and coherent phenomena in crystals

abstract:
  We study coherent enhancement of Coulomb excitation of high energy particles
in crystals. We develop multiple scattering theory description of coherent
excitation which consistently incorporates both the specific resonant
properties of particle-crystal interactions and the final/initial state
interaction effects typical of the diffractive scattering. Possible
applications to observation of induced radiative neutrino transitions are
discussed.


title:
Non-perturbative renormalization group approach for a scalar theory in
  higher-derivative gravity

abstract:
  A renormalization group study of a scalar theory coupled to gravity through a
general functional dependence on the Ricci scalar in the action is discussed. A
set of non-perturbative flow equations governing the evolution of the new
interaction terms generated in both local potential and wavefunction
renomalization is derived. It is shown for a specific model that these new
terms play an important role in determining the scaling behavior of the system
above the mass of the inflaton field.


title: Soft Gluon Radiation in Higgs Boson Production at the LHC

abstract:
  We examine the contributions of soft gluons to the Higgs production cross
section at the LHC in the Standard Model and its minimal supersymmetric
extension. The soft gluon radiation effects of this reaction share many
features with the Drell-Yan process, but arise at lowest order from a purely
gluonic initial state. We provide an extension of the conventional soft gluon
resummation formalism to include a new class of contributions which we argue to
be universal, and resum these and the usual Sudakov effects to all orders. The
effect of these new terms is striking: only if they are included, does the
expansion of the resummed cross section to next-to-leading order reproduce the
exact result to within a few percent for the full range of Higgs boson masses.
We use our resummed cross section to derive next-to-next-to-leading order
results, and their scale dependence. Moreover, we demonstrate the importance of
including the novel contributions in the resummed Drell-Yan process.


title:
Supersymmetric models with anomalous U(1) mediated supersymmetry
  breaking

abstract:
  We construct realistic supergravity models where supersymmetry breaking
arises from the D-terms of an anomalous U(1) gauge symmetry broken at the
Planck scale. Effective action for these theories at sub-Planck energies
(including higher dimensional terms in the superpotential) are severely
restricted by the U(1) symmetry and by the assumption that they arise from an
underlying renormalizable theory at a higher scale. Phenomenological
consequences of these models are studied. They are found to have the attractive
feature that the gaugino masses, the A and B terms and the mass splittings
between the like-charged squarks of the first two generations compared to their
average masses can all be naturally suppressed. As a result, the electric
dipole moment of the neutron as well as the flavor changing neutral current
effects are predicted to be naturally small. These models also predict the
value of the $\mu$-term to be naturally small and have the potential to
qualitatively explain the observed mass hierarchy among quarks and leptons. We
then discuss examples of high scale renormalizable theories that can justify
the choice of the the effective action from naturalness point of view.


title: Flaton Inflation Model

abstract: withdrawn for revision


title:
How to Distinguish Hydrodynamic Models Utilizing Particle Correlations
  and Spectra ?

abstract:
  We demonstrate on examples that a simultaneous study of the Bose-Einstein
correlation function and the invariant momentum distribution can be very useful
in distinguishing various hydrodynamic models, which describe separately the
short-range correlations in high energy hadronic reactions as measured by the
NA22 collaboration. We also analyze Bose-Einstein correlation functions,
measured by the NA44 experiment at CERN SPS, in the context of the core-halo
model.


title: eta->pi0 pi0 gamma gamma to 1-Loop in ChPT

abstract:
  1. Introduction: a) motivations, b) status, c) purpose, d) results 2.
Kinematics and couplings 3. Decay amplitude (analytic expression): a) tree
level, b) one loop 4. Decay width (numerical): a) diphoton energy spectrum
[energy cut] 5. Discussion: detectability of chiral loop effects (background
suppression)


title: Anomalous U(1) symmetry and missing doublet SU(5) model

abstract:
  We present the supersymmetric $SU(5)$ models which provide a simple ``all
order'' solution to the doublet-triplet splitting problem through the missing
doublet mechanism. The crucial role is played by the anomalous $U(1)_A$ gauge
symmetry and no additional discrete or global symmetries are needed.
Remarkably, such models can be realized even if the 75-plet Higgs is replaced
by the standard 24-plet. The same $U(1)_A$ symmetry can also guarantee an exact
or approximate conservation of R parity, by suppressing the B and L violating
operators to the needed level. The neutrino masses and the proton decay via
$d=5$ operators are also examined. We also extend the model by incorporating
$U(1)_A$ as a horizontal symmetry for explaining the fermion mass and mixing
hierarchy. Interestingly, in this scheme the necessary mild violation of the
troublesome $SU(5)$ degeneracy between the down quark and the charged lepton
masses can be induced by certain R-parity violating operators.


title: Rapidity gaps in perturbative QCD

abstract:
  We analyze diffractive deep inelastic scattering within perturbative QCD by
studying lepton scattering on a heavy quark target. Simple explicit expressions
are derived in impact parameter space for the photon wave function and the
scattering cross sections corresponding to single and double Coulomb gluon
exchange. At limited momentum transfers to the target, the results agree with
the general features of the ``aligned jet model''. The color--singlet exchange
cross section receives a leading twist contribution only from the aligned jet
region, where the transverse size of the photon wave function remains finite in
the Bjorken scaling limit. In contrast to inclusive DIS, in diffractive events
there is no leading twist contribution to $\sigma_L/\sigma_T$ from the lowest
order $(q\bar q)$ photon Fock state, and the cross section for heavy quarks is
power suppressed in the quark mass. There are also important contributions with
large momentum transfer to the target, which corresponds to events having high
transverse momentum production in both the projectile and target rapidity
regions, separated by a rapidity gap.


title: Physics of Heavy Quarks from Lattice QCD

abstract:
  In the last few years, lattice QCD has made a dramatic progress in
understanding the physics of hadrons containing heavy quarks, from the first
principle. This review summarises the major achievements.


title: Sparticle and Higgs masses within minimal string unification

abstract:
  We consider the sparticle and higgs spectroscopy in a class of superstring
inspired models in which the string threshold corrections ensure the
consistency of the string unification scale with the low energy data. The
lightest neutralino is almost a pure bino and it is predicted to be the
lightest sparticle (LSP). Requiring that $\Omega_{LSP}\leq 0.9$, we find an
upper bound on its mass which, in the case of dilaton supersymmetry breaking,
turns out to be 160 GeV. The LEP 1.5 experimental lower bound on the chargino
mass, $m_{\chi^{\pm}} > 65$ GeV, implies that the lower bound on the LSP mass
is $m_{LSP} > 32 (45)$ GeV, corresponding to $\mu < (>)0$. We also determine
the lower and upper bounds on the higgs and other sparticle masses. For
instance, the lightest higgs lies between 65 and 115 GeV, while the mass of the
lightest charged sparticle satisfies 47 GeV $ < m_{\tilde{e}_R} < 325$ GeV.
With only the top Yukawa coupling of order unity we find that $ 1.5 \leq \tan
\beta \leq 3.5$.


title: Supersymmetric Sum Rules In Minimal Superstring Unification

abstract:
  The Minimal superstring unification, assuming orbifold compactification,
provides interesting and rather detailed implications on physics at low energy.
The interesting feature of this model is that the masses of the spectrum are
related since all of them are functions of only two parameters: the goldstino
angle theta and the gravitino mass m_{3/2}. This fact will help us in studying
the modification of the supersymmetric magnetic moments sum rules which are
very sensitive to the supersymmetry breaking. We write these rules in case of
exact supersymmetry in a form close to the supersymmetric mass relations,
namely $ \sum_J (-1)^{(2J)} (2 J) A_J=0$, where A_J is the anomalous magnetic
moment of the spin J particle. We show that the anomalous magnetic moments of
the W-boson and the gauginos can be written as functions of theta and m_{3/2}.
Then we obtain a modified version of the supersymmetric magnetic moment sum
rule in the context of the minimal superstring unification.


title: Search for flavor lepton number violation in slepton decays at LHC

abstract:
  We show that in supersymmetric models with explicit flavor lepton number
violation due to soft supersymmetry breaking mass terms there could be
detectable flavor lepton number violation in slepton decays. We estimate LHC
discovery potential of the lepton flavor number violation in slepton decays.


title: Single meson photoproduction and IR renormalons

abstract:
  Single pseudoscalar and vector mesons inclusive photoproduction $\gamma
h\rightarrow MX$ via higher twist mechanism is calculated using the QCD running
coupling constant method. It is proved that in the context of this method a
higher twist contribution to the photoproduction cross section cannot be
normalized in terms of the meson electromagnetic form factor. The structure of
infrared renormalon singularities of the higher twist subprocess cross section
and the resummed expression (the Borel sum) for it are found. Comparisons are
made with earlier results, as well as with leading twist cross section.
Phenomenological effects of studied contributions for $\pi, K, \rho$-meson
photoproduction are discussed.


title: CP violation in kaon decays

abstract:
  We review the Standard Model predictions of CP violation in kaon decays. We
present an elementary introduction to Chiral Perturbation Theory, four--quark
effective hamiltonians and the relation among them. Particular attention is
devoted to $K\to 3\pi$, $K\to 2\pi \gamma$ and $K\to \pi \bar{f} f$ decays.


title: Proton Decay with a Light Gravitino or Axino

abstract:
  We consider the proton decay in supersymmetric models with a gravitino or
axino lighter than the proton. This consideration leads to a stringent limit on
the R parity and B violating Yukawa coupling of the superpotential operator
U^c_i D^c_j D^c_k as $\lambda"_{112} < 10^{-15} (m_{3/2}/eV)$ for a light
gravitino, and $\lambda"_{112} < 10^{-15} (F_a/ 10^{10} GeV)$ for a light DFSZ
axino. For hadronic axino, the constraint is weakened by the factor of 10^{3}.


title:
Infra-red fixed point structure characterising SUSY SU(5) symmetry
  breaking

abstract:
  We analyze the one-loop renormalisation group equations for the parameters of
the Higgs potential of a supersymmetric SU(5) model with first step of symmetry
breaking involving an adjoint Higgs. In particular, we investigate the running
of the parameters that decide the first step of symmetry breaking in an attempt
to establish which symmetry-breaking scenarios would be most likely if the
model is the effective low-energy description of some more fundamental theory.
An infra-red fixed point is identified analytically. We show that it is located
at the boundary between the region of Higgs parameter space corresponding to
unbroken SU(5) and the region corresponding to the breaking of SU(5) to the
Standard Model, and we elaborate on its implications. We also observe that
certain forms of the Higgs potential discussed at tree level in the literature
are not renormalisation group invariant.


title:
A grand unified model with $M_G\sim M_{string}$ and $M_I\sim 10^{12}$
  GeV

abstract:
  We present a model based on the gauge group SU(2)_L\times SU(2)_R \times
SU(4)_C with gauge couplings that are found to be unified at a scale near the
string unification scale. This model breaks to the MSSM at an intermediate
scale which is instrumental in producing a neutrino in a mass range that can
serve as hot dark matter and can also solve the strong CP problem via a
harmless invisible axion.


title: Heavy Baryon Masses in Large N_c HQET

abstract:
  We argue that in the large N_c HQET, the masses of the s-wave low-spin heavy
baryons equal to the heavy quark mass plus proton mass approximately. To the
subleading order, the heavy baryon mass 1/N_c expansion not only has the same
form, but also has the same coefficients as that of the light baryon. Based on
this, numerical analysis is made.


title: Non-commuting ETC corrections to zt\bar{t} vertex

abstract:
  In this paper we calculate the corrections to zt\bar {t} couplings induced by
non-commuting ETC interactions. The extra parameters \delgbl, s^2 and {1\over
x} of non-commuting ETC models and the usual SM parameters will be be assumed
to be determined from a global fit to the LEP 1 EW data. We find that in the
heavy (light) case F^t_L is modified by at most 4% (2.8%) relative to its SM
value provided \delrb < .0088. This implies that it will be very difficult to
disentangle the ETC corrections from SM corrections to zt\bar {t} vertex or to
probe the effects of non-commuting ETC on zt\bar {t} couplings with the
projected NLC precision of measuring them.


title: Multiparticle Clusters and Intermittent Fluctuations

abstract:
  An approach for understanding the behavior of multiplicity distributions in
restricted phase-space intervals derived on the basis of global observables is
proposed. We obtain a unifying connection between local multiparticle clusters
and the scale-invariant power-law behavior of normalized factorial moments. The
model can be used to describe multiparticle processes in terms of a
decomposition of the observed intermittent signal into contributions from
clusters with varying number of particles.


title:
Lepton flavor violation and electric dipole moments from an intermediate
  scale in SUSY grand unification

abstract:
  We show how an intermediate gauge symmetry breaking scale can be a source of
lepton flavor violation and EDM of electron and neutron in SUSY GUTs. The
Universal soft supersymmetry breaking operators can be introduced at the GUT
scale or above.


title: Classical Lattice Gauge Fields with Hard Thermal Loops

abstract:
  We propose a formulation of the long-distance dynamics of gauge theories at
finite temperature on a lattice in Minkowski space, including the effects of
hard thermal loops on the dynamics of the long wavelength modes. Our approach
is based on the dual classical limits of quantum fields as waves and particles
in the infrared and ultraviolet limits, respectively. It exhibits manifest
invariance under space-dependent lattice gauge transformations and conserves
Gauss' law.


title: Supersymmetry Hierarchy Problems and Anomalous Horizontal U(1) Symmetry

abstract:
  It is suggested that various hierarchy problems in supersymmetric standard
model, i.e. the Yukawa hierarchies, the \mu problem, and the suppression of
dangerous baryon and/or lepton number (B/L) violating couplings, are resolved
altogether in the framework of horizontal U(1) symmetry whose spontaneous
breaking results in the appearance of one expansion parameter (the Cabibbo
angle). Within a reasonable range of U(1) charges, there exist a few models
compatible with experiments. The specific sizes of B/L violating couplings of
these models are calculated and several phenomenological consequences are
discussed.


title:
Radiative Tail in $\pi_{e2}$ Decay and Some Comments on $\mu-e$
  Universality

abstract:
  The result of lowest-order perturbation theory calculations of the photon and
positron spectra in radiative pion(e2) decay are generalized to all orders of
perturbation theory using the structure-function method. An additional source
of radiative corrections to the ratio of the positron and muon channels of pion
decay, due to emission of virtual and real photons and pairs, is considered. It
depends on details of the detection of the final particles and is large enough
to be taken into account in theoretical estimates with a level of accuracy of
0.1%.


title:
Particle production by time-dependent meson fields in relativistic
  heavy-ion collisions

abstract:
  Collective bremsstrahlung of vector meson fields caused by mutual
deceleration of the colliding nuclei is considered within the time-dependent
Walecka theory. Excitation functions and rapidity distributions of particles
produced by this mechanism are calculated under some simplifying assumptions
about the space-time variation of the baryon current in a nuclear collision. In
the case of central Au+Au collisions the bremsstrahlung mechanism becomes
comparable with particle production in incoherent hadron--hadron collisions
above the AGS energies.


title: Electromagnetic Masses of the Massive Yang-Mills Particles K^*(892)

abstract:
  Electromagnetic mass difference between neutral $K^*$ and charged $K^*$ has
been calculated in the $U(3)_L\times U(3)_R$ chiral fields theory of mesons. It
has been revealed that the non-abelian gauge structure of the massive
Yang-Mills lagrangian obeyed by $K^*$ plus VMD (vector meson dominace) causes
the EM-mass of neutral one larger than charged one. Experiment supports this
effect.


title:
Electromagnetic mass splittings of $\pi, a_1, K, K_1(1400)$ and
  $K^*(892)$

abstract:
  To one-loop order and $O(\alpha_{em})$, the electromagnetic mass splittings
of $\pi$, $a_1$, $K$, $K_1(1400)$, and $K^*(892)$ are calculated in the
framework of $U(3)_L\times U(3)_R$ chiral field theory. The logarithmic
divergences emerging in the Feynman integrations of the mesonic loops are
factorized by using an intrinsic parameter $g$ of this theory. No other
additional parameters or counterterms are introduced to absorb the mesonic loop
divergences. When $f_\pi$,$m_\rho$ and $m_a$ are taken as inputs, the parameter
$g$ will be determined and all the physical results are finite and fixed.
Dashen's theorem is satisfied in the chiral SU(3) limit of this theory, and a
rather large violation of the theorem is revealed at the order of $m_s$ or
$m_K^2$. Mass ratios of light quarks have been determined. A relation for
electromagnetic corrections to masses of axial-vector mesons is obtained. It
could be regarded as a generalization of Dashen's theorem. Comparing with data,
it is found that the non-electromagnetic mass difference of $K^*$ is in
agreement with the estimation of Schechter, Subbaraman, Weigel.


title:
PLANCKSUSY - new program for SUSY masses calculations: from Planck scale
  to our reality

abstract:
  We describe briefly new program for SUSY masses calculations. The main
distinction of our program is that we start to solve the renormalization group
equations for soft SUSY breaking parameters for SU(5) SUSY GUT model from
Planck scale $M_{PL} = 2.4\cdot 10^{18}$ Gev. Our program works also for large
$tan(\beta)$. We find that for $m_0 \leq 0.5 \cdot m_{1/2}$ the effects of the
evolution from Planck scale to GUT scale are very essential. In particular, we
find that neutralino even for small $m_0$ is always LSP. We also introduced in
our program some parameter of non-universality of the gaugino masses at GUT
scale. Playing with the non-universality of the gaugino masses at GUT scale it
is possible to have the situation when leptonic modes are suppressed and the
single SUSY signature is hadronic jets with missing energy.


title: On the Dipole Moments of Fermions at Two Loops

abstract:
  Complete two-loop electroweak corrections to leptonic anomalous magnetic
moments have been calculated recently using asymptotic expansions of Feynman
diagrams. Techniques developed in that context can also be applied to the
electric dipole moments (EDM) of fermions. In the Standard Model the EDM was
proved to vanish at two loops. In this talk we discuss a simplification of that
proof.


title: Rho meson properties in the Nambu-Jona-Lasinio model

abstract:
  Some properties of the rho vector meson are calculated within the
Nambu-Jona-Lasinio model, including processes that go beyond the random phase
approximation. To classify the higher order contributions, we adopt $1/N_c$ as
expansion parameter. In particular, we evaluate the leading order contributions
to the $\rho \rightarrow \pi \pi$ decay width, obtaining the value $\Gamma =
118$ MeV, and to the shift of the rho mass which turns out to be lowered by 64
MeV with respect to its RPA value. A set of model parameters is determined
accordingly.


title: Review of Atmospheric Neutrinos

abstract:
  In this talk I review measurements and calculations of the flux of neutrinos
produced by interactions of cosmic rays in the atmosphere. The main reason for
interest in this subject is the apparent anomaly between the predicted and the
observed ratio of $\nu_e$ to $\nu_\mu$. With the advent of Super-Kamiokande, we
are on the threshold of an order of magnitude increase in the amount of data
available to study the problem. My goal in this talk is to describe the current
status of the subject, both for contained events and for neutrino-induced
upward muons.


title: Supersymmetric QCD correction to top-quark production at the Tevatron

abstract:
  We calculate the supersymmetric QCD correction to top-quark production at the
Fermilab Tevatron, allowing for arbitrary left-right mixing of the squarks. We
find that the correction is significant for several combinations of gluino and
squark masses, e.g. +33% for m_{\tilde g}=200 GeV, m_{\tilde t} = m_{\tilde q}
=75 GeV.


title: How strange a non-strange heavy baryon?

abstract:
  We give some general arguments in favor of the large magnitude of matrix
elements of an operator associated with nonvalence quarks in heavy hadrons. We
estimate a strange matrix element for \Lambda_b baryon whose valence content is
b, u, d quarks. We find a noticeable contribution of the strange quark into the
heavy baryon mass on the level 200-300 MeV. The arguments are based on the QCD
sum rules and low energy theorems. The physical picture behind of the
phenomenon is somewhat similar to the one associated with the large strange
content of the nucleon where matrix element. We discuss some possible
applications of the obtained result.


title: CP Violation in $t\to W^+ b$ Decays in Two-Higgs Doublet Model

abstract:
  Due to the large mass of top quark, CP violation in the top-quark decay is
sensitive to the interactions mediated by Higgs bosons. We consider CP
violation in $t\rightarrow W^+ b$ decay by calculating consistently in unitary
gauge the CP-violating up-down asymmetry of the leptons from $W$ boson decays
in $t\rightarrow W^+ b$, defined by Grz\c{a}dkowski and Gunion, in the
two-Higgs doublet model with CP-violating neutral sector. The asymmetry is
shown to be at most of the order of $(1-3)\times 10^{-4}$ for $\tan\beta=1.0$,
where $\tan\beta$ is the ratio of vacuum expectation values for the two neutral
Higgs bosons.


title: Medium effects in strange quark matter and strange stars

abstract:
  We investigate the properties of strange quark matter at zero temperature
including medium effects. The quarks are considered as quasiparticles which
acquire an effective mass generated by the interaction with the other quarks of
the dense system. The effective quark masses are derived from the zero momentum
limit of the dispersion relations following from an effective quark propagator
obtained from resumming one-loop self energy diagrams in the hard dense loop
approximation. This leads to a thermodynamic selfconsistent description of
strange quark matter as an ideal Fermi gas of quasiparticles. Within this
approach we find that medium effects reduce the overall binding energy with
respect to $^{56}Fe$ of strange quark matter. For realistic values of the
strong coupling constant strange quark matter is not absolutely stable. The
application to pure strange quark matter stars shows that medium effects have,
nevertheless, no impact on the mass-radius relation of the stars. However, a
phase transition to hadronic matter at the surface of the stars becomes more
likely.


title: Introduction to the Pomeron

abstract:
  Elements of the pomeron phenomenology within the Regge pole exchange picture
are recalled. This includes discussion of the high energy behaviour of total
cross-sections, the triple pomeron limit of the diffractive dissociation and
the single particle distributions in the central region. The BFKL pomeron and
QCD expectations for the small $x$ behaviour of the deep inelastic scattering
structure functions are discussed. The dedicated measurements of the hadronic
final state in deep inelastic scattering at small $x$ probing the QCD pomeron
are described. The deep inelastic diffraction is also discussed.


title: Unitarity, Chiral Perturbation Theory, and Meson Form Factors

abstract:
  The inverse-amplitude method is applied to the one-loop chiral expansion of
the pion, kaon, and $K_{l3}$ form factors. Since these form factors are
determined by the same chiral low-energy constants, it is possible to obtain
finite predictions for the inverse-amplitude method. It is shown that this
method clearly improves one-loop chiral perturbation theory, and a very good
agreement between the inverse-amplitude method and the experimental information
is obtained. This suggests that the inverse-amplitude method is a rather
systematic way of improving chiral perturbation theory.


title: Scaling and scale breaking phenomena in QCD jets

abstract:
  The perturbative QCD approach to multiparticle production assuming Local
Parton Hadron Duality (LPHD) and some recent results are discussed. Finite
asymptotic scaling limits are obtained for various observables, after an
appropriate rescaling, in the Double Logarithmic Approximation (DLA).
Non-asymptotic corrections are also known in some cases. The DLA applies also
to very soft particle production where energy conservation constraints can be
neglected. In this region the particle density follows rather well a scaling
behaviour over the full energy range explored so far in $e^+e^-$ annihilation.


title: Are the Supersymmetric Higgs Particles Pseudo-Goldstone Bosons?

abstract:
  A promising solution to the doublet-triplet splitting problem of SUSY GUT's
is the Higgs as pseudo-Goldstone boson mechanism. We present two models which
naturally implement this idea and extend one of them to include fermion masses.
We examine the phenomenological consequences of this mechanism and present the
favored parameter region.


title: On the Dirac Structure of Confinement

abstract:
  The Dirac structure of confinement is shown to be of timelike-vector nature
in the heavy quark limit of QCD. This stands in contradiction with the
phenomenological success of the Dirac scalar confining potential. A resolution
is achieved through the demonstration that an effective scalar interaction is
dynamically generated by nonperturbative mixing between ordinary and hybrid $Q
\bar Q$ states. The resolution depends crucially on the collective nature of
the gluonic degrees of freedom. This implies that dynamical gluonic effects are
vital when attempting to incorporate fine structure in models of the $Q \bar Q$
interaction.


title: Isospin Breaking and Instantons in QCD Nucleon Sum Rules

abstract:
  We study isospin breaking instanton corrections to the operator product
expansion of the nucleon correlation functions. After a comparison with quark
model calculations based on the 't Hooft interaction, we examine the role of
instantons in the corresponding QCD sum rules. Instanton contributions are
found to be absent in the chirally even sum rule, but significant in the
chirally-odd one. They improve the consistency of both sum rules and favor a
value of the isovector quark condensate close to the chiral estimate.


title: New Collider Bound on Light Gravitino Mass

abstract:
  In supergravity theories with a very light gravitino, the gluino decays
dominantly to a gluon and a gravitino. This results in a much larger missing
$E_T$ for the multijet final states in hadronic colliders. We use the latest
Tevatron data for the multijet final states to set a new absolute lower bound
of 3.0 x 10^{-13} GeV for the light gravitino mass.


title: Derivation of the Lamb Shift using an Effective Field Theory

abstract:
  We rederive the $O(\alpha^5)$ shift of the hydrogen levels in the non-recoil
($m_e/m_P \to 0$) limit using Nonrelativistic QED (NRQED), an effective field
theory developed by Caswell and Lepage (Phys. Lett. 167B, 437 (1986)). Our
result contains the Lamb shift as a special case. Our calculation is far
simpler than traditional approaches and has the advantage of being systematic.
It also clearly illustrates the need to renormalize (or ``match'') the
coefficients of the effective theory beyond tree level.


title: Spin Correlations in Top Quark Production and the Top Quark Mass

abstract:
  Top-antitop quark pairs produced at the Tevatron have a sizeable spin
correlation. That correlation feeds into the angular distribution of the decay
products, particularly in the dilepton channel. Including the expected
correlation in an overall analysis of a handful of actual dilepton events
continues to favor a lower top mass (centered on 155 GeV) than the single
lepton events.


title: Hara's Theorem and W-exchange in Hyperon Weak Radiative Decays

abstract:
  We reconsider Hara's theorem in its relation to the well-known properties of
beta-decay. All assumptions necessary for the theorem to be true are explicitly
formulated. Further, we study the W-exchange contribution to weak radiative
decays and show that it does not violate Hara's theorem. However, this
contribution reveals the essential role of particle mixing in symmetry
considerations and some peculiar features of gauge-invariant amplitudes under
perturbative expansion. Together they explain an effect, which was treated as
contradicting Hara's theorem, without any violation. The properties of
W-exchange we describe here may have more general importance and should be
taken into account in further detailed calculations of weak processes.


title:
Estimating The Sensitivity Of The LHC To Electroweak Symmetry Breaking:
  Longitudinal-Goldstone Boson Equivalence As A Criterion

abstract:
  Based upon our recent study, we reveal the profound physical content of the
longitudinal-Goldstone boson equivalence theorem as being able to discriminate
physical processes which are sensitive/insensitive to probing the electroweak
symmetry breaking (EWSB) sector. We then develop a precise electroweak power
counting rule (a generalization from Weinberg's counting method) to
`separately' count the power dependences on the energy E and all relevant mass
scales. With these, we analyze the complete set of the bosonic operators in the
electroweak chiral Lagrangian and systematically estimate and classify the
sensitivities for testing all these effective operators at the CERN LHC via the
weak-boson fusions and quark-anti-quark annihilations. These two kinds of
processes are shown to be `complementary' in probing the EWSB mechanism.


title: Hadron Multiplicities at the Energies of LEP-1.5 and LEP-2

abstract:
  Total hadron multiplicities and multiplicities of hadrons in events with
heavy quarks in $e^+e^-$ annihilation at the energies of LEP-1.5 and LEP-2 are
calculated on the basis of QCD.


title: Dependence of Deep Inelastic Structure Functions on Quark Masses

abstract:
  We argue that the difference between the structure functions corresponding to
deep inelastic scattering with and without heavy quarks in the current
fragmentation region scales at high $Q^2$ and fixed (low) $x_{Bj}$. The lower
bound on charm contribution to the total structure function, $F_2^c(Q^2,x)$, is
calculated and compared with the recent data on $F_2^c(Q^2,x)$ from H1
Collaboration.


title: Supersymmetric Grand Unified Theories and Global Fits to Low Energy Data

abstract:
  We present a self-consistent $\chi^2$ analysis of several supersymmetric
(SUSY) grand unified theories recently discussed in the literature. We obtain
global fits to low energy data, including gauge couplings, fermion masses and
mixing angles, gauge boson masses and $BR(b\rightarrow s\gamma)$. One of the
models studied provides an excellent fit to the low energy data with
$\chi^2\sim 1$ for 3 degrees of freedom, in a large region of the
experimentally allowed SUSY parameter space. We also discuss the consequences
of our work for a general MSSM analysis at the $Z$ scale.


title:
Determining the beta-function of the strong interaction and closing the
  light gluino window

abstract:
  We discuss the perturbative running of alpha_s in a model independent way.
Our analysis contains data on the hadronic tau decay and hadronic cross
sections in e+e- annihilation between 5 GeV and M_Z. We determine the color
coefficients and the perturbative beta-function of the strong interaction. The
results are in agreement with QCD and rule out the QCD+light gluino scenarios
on the 70.8 - 93.0% CL. We combine our method with that of the multi-jet
analysis at LEP. The combined result rules out light gluinos at least on the
99.76% CL, provided that nonperturbative effects are not large.


title: Testing Quarkonium Production with Photoproduced $J/\psi + \gamma$

abstract:
  I compute the leading color-octet contributions to the process $\gamma + p
\to J/\psi + \gamma (+ X)$ within the non-relativistic QCD (NRQCD)
factorization formalism. In the color-singlet model, $J/\psi + \gamma$ can only
be produced when the photon interacts through its structure function, while the
color-octet mechanism allows for production of $J/\psi + \gamma$ via direct
photon-gluon fusion. Resolved photon processes can be easily be distinguished
from direct photon processes by examining the fraction of the incident photon
energy carried away by the $J/\psi$ in the event. Therefore, this process
provides a conclusive test of the color-octet mechanism. $J/\psi + \gamma$
production is particularly sensitive to the NRQCD matrix element which figures
prominently in the fragmentation production of $J/\psi$ at large $p_{\perp}$ in
hadron colliders. I also examine the predictions of the color evaporation model
(CEM) of quarkonium production and find that this process can easily
discriminate between the NRQCD factorization formalism and the CEM.


title: QCD Sum Rule for 1/2- Baryons

abstract:
  The masses of the flavor octet and singlet baryons with negative parity and
spin 1/2 are calculated using the QCD sum rule. We find that the chiral
symmetry breaking vacuum condensates cause the mass splitting of the positive
and negative baryons. The present sum rule reproduces the observed masses of
these baryons within 10%, and predicts the mass of the excited Xi baryon with
$J^P = {1/2}^{-}$ at 1.63 GeV. We confirm that the negative-parity state,
$\Lambda_S-$, is the ground state in the flavor singlet baryon spectrum.


title:
Explicit Solutions to the Unitarity Relations for Isovector Nucleon Form
  Factors

abstract:
  The explicit one-dimensional integral representations for isovector nucleon
form factors are constructed by solving the unitarity relations in terms of the
pion form factor and imaginary parts of the t-channel p-wave $\pi N$-scattering
amplitudes. The possibility of computation of the high-energy parts of the
integrals with the use of the information on the low-energy real parts of the
$\pi N$-scattering amplitudes is discussed.


title:
Associated J/psi + gamma Photoproduction as a Probe of the Colour-Octet
  Mechanism

abstract:
  The associated production of a J/psi and a photon in photon-hadron collisions
is considered, and shown to be a good probe of the presence of colour-octet
mediated channels in quarkonia production, as predicted by the factorization
approach within NRQCD. Total and differential cross sections for
photoproduction at fixed target experiments and at HERA are presented.
Associated J/psi + gamma production at hadron colliders is briefly discussed.


title: Constraints from Inflation and Reheating on Superpartner Masses

abstract:
  Flat directions in the Minimal Supersymmetric Standard Model (MSSM) can
become unstable due to radiative corrections, and the global minimum of the
(zero temperature) potential can lie at large values of the squark and/or
slepton fields. Here we show that, in inflationary models of early cosmology,
the universe is very likely to be in the domain of attraction of this global
minimum at the end of inflation. While the minimum at the origin of field space
is global at sufficiently high temperatures, depending on details of the model,
the universe may be trapped in the non-zero minimum until it becomes the global
minimum at low temperatures. Parameter values leading to this scenario are
therefore ruled out.


title: Gluon Polarization from QCD Sum Rules

abstract:
  The gluon polarization $\Delta G$ in a nucleon can be defined in a gauge
invariant way as the integral over the Ioffe-time distribution of polarized
gluons. We argue that for sufficiently regular polarized gluon distributions
$\Delta G$ is dominated by contributions from small and moderate values of the
Ioffe-time z < 10. As a consequence $\Delta G$ can be estimated with 20%
accuracy from the first two even moments of the polarized gluon distribution,
and its behavior at small values of Bjorken x or, equivalently, at large
Ioffe-times z. We employ this idea and compute the first two moments of the
polarized gluon distribution within the framework of QCD sum rules. Combined
with the color coherence hypothesis we obtain an upper limit for $\Delta G \sim
2 \pm 0.5$ at a typical scale $\mu^2 \sim 1 GeV^2$.


title: Measuring the mass of the W at the LHC

abstract:
  We explore the ability of the Large Hadron Collider to measure the mass of
the W boson. We believe that a precision better than ~ 15 MeV could be
attained, based on a year of operation at low luminosity
(10^(33)cm^(-2)s^(-1)). If this is true, this measurement will be the world's
best determination of the W mass. We feel this interesting opportunity warrants
investigation in more detail.


title: Low-mass dileptons at the SPS

abstract:
  We use a simple QCD-based model to study particle production in S+Au
collisions at 200 GeV/n. A requisite consistency is met for the hadronic
observables (pi0 and pi- spectra) while pursuing estimates for e+e- production.
Since radiative decays of initially produced hadrons has accounted for only a
portion of the observed dileptons at the CERN SPS, we search for additional
mechanisms. By including contributions from prompt secondary hadronic
scatterings, pi rho -> pi e+e-, and adding to pi+ pi- annihilation and hadronic
decays, the ``excess'' dilepton signal can possibly be interpreted.


title: Structure Functions in Semihadronic Tau Decays

abstract:
  We review a variety of topics related to hadronic structure functions in
exclusive semihadronic tau decays. We introduce the concept of structure
functions and summarize the most important concepts. We then calculate the
decay $\tau \to 3 \pi \nu_\tau$ for very small hadronic invariant mass to one
loop in Chiral Perturbation Theory. New interesting features emerge with
respect to the known results at tree level, in particular for the structure
functions $w_D$ and $w_E$. We discuss the prospects for experimental
verification of our predictions. Finally, we discuss various issues at higher
$Q^2$, related to hadronic resonance physics. Here we consider $2\pi$, $\pi K$,
$3 \pi$, $K \pi K$ and $\pi K \pi$ hadronic final states.


title: Production of eta Mesons in Double Pomeron Exchange

abstract:
  We estimate the production cross sections for $\eta_c$ and $\eta_b$ mesons
via pomeron-pomeron fusion in peripheral heavy-ion collisions. Total and
elastic PP cross sections are calculated in an equivalent pomeron
approximation.


title: The Electromagnetic Mass Differences of Pions and Kaons

abstract:
  We use the Cottingham method to calculate the pion and kaon electromagnetic
mass differences with as few model dependent inputs as possible. The
constraints of chiral symmetry at low energy, QCD at high energy and
experimental data in between are used in the dispersion relation. We find
excellent agreement with experiment for the pion mass difference. The kaon mass
difference exhibits a strong violation of the lowest order prediction of
Dashen's theorem, in qualitative agreement with several other recent
calculations.


title: Electroweak Radiative Corrections to W Boson Production at the Tevatron

abstract:
  We present some results of a new calculation of the O(alpha) electroweak
radiative corrections to W boson production at hadron colliders with special
emphasis on the transverse mass distribution.


title:
$0^{++}$-Glueball/$q \bar q$-State Mixing in the Mass Region near 1500
  MeV

abstract:
  Basing on the results of the K-matrix fit of $(IJ^{PC}=00^{++})$ wave, we
analyze the analytic structure of the amplitude and $q \bar q$/glueball content
of resonances in the mass region 1200-1900 MeV, where an extra state for $q
\bar q$-systematics exists being a good candidate for the lightest scalar
glueball. Our analysis shows that the pure glueball state dispersed over three
resonances: $f_0(1300)$, $f_0(1500)$ and $f_0(1530^{+90}_{-250})$, while the
glueball admixture in $f_0(1750)$ is small. The broad resonance
$f_0(1530^{+90}_{-250})$ is the descendant of the lightest pure glueball. The
mass of pure glueball is $1630\pm {70\atop 30}$ MeV, in agreement with Lattice
calculation results.


title: Precision Electroweak Physics at Future Collider Experiments

abstract:
  We present an overview of the present status and prospects for progress in
electroweak measurements at future collider experiments leading to precision
tests of the Standard Model of Electroweak Interactions. Special attention is
paid to the measurement of the W mass, the effective weak mixing angle, and the
determination of the top quark mass. Their constraints on the Higgs boson mass
are discussed.


title: Aspects of the Electroweak Theory

abstract:
  These notes contain some of the material I presented at TASI 96 on the
comparison of the standard model with precision electroweak data. After a
physical accounting of the dominant electroweak radiative corrections,
including the effects of initial state bremsstrahlung, I examine how data from
LEP and the SLC provides a clear test of the standard model. Apparent
discrepancies in the $R_b$ and $R_c$ ratios, and their physical resolution, are
also examined in some detail.


title: Systematics Effects in $Z'$ Searches at the NLC

abstract:
  We investigate the incidence of several systematic effects on the $Z'$
discovery limits of the NLC. These include the initial state radiation and the
systematic errors due to the imperfect polarization measurement, the finite
detector angular resolution and the uncertainty on the integrated luminosity.
We focus on three reactions involving leptonic couplings: muon pair production,
Bhabha scattering and M\o ller scattering.


title:
Production of meson pairs, involving tensor and pseudotensor mesons, in
  photon-photon collisions

abstract:
  Starting from a bound-state model of weakly bound quarks for ($q \bar{q}$)
mesons, we derive a formalism for computing the production or decay of such
mesons, whatever the value of their internal orbital angular momentum L. That
approach appears as a natural generalization of the Brodsky-Lepage formalism
(valid only for L=0) that has been widely used in recent years for the
computation of exclusive processes in perturbative QCD. We here apply it to the
production, in photon-photon collisions, of: i) tensor-meson pairs; ii)
pseudotensor-meson pairs; iii) hybrid pairs made of a pion and a pseudotensor
meson. The numerical results we obtain allow for some hope of experimentally
identifying such pairs, in the charged channels, at high-energy e^+e^-
colliders of the next generation, provided integrated luminosities as high as
$\approx 10^{40} cm^{-2}$ can be reached.


title: On hard exclusive reactions in the time-like region

abstract:
  The proton form factor, two-photon annihilations into $p\bar{p}$ as well as
exclusive charmonium decays are critically examined. It will be argued that the
standard perturbative QCD analysis of these reactions fails, i.e. the need for
additional contributions can convincingly be demonstrated. Possible dynamical
mechanisms such as colour-octet admixtures to the charmonium states or diquarks
inside baryons, will be discussed and compared to the data.


title: Dark matter axions '96

abstract:
  Contents: 1. The strong CP problem 2. Dark matter axions 3. The cavity
detector of galactic halo axions 4. The phase space structure of cold dark
matter halos


title: Universal Behavior in Excited Heavy-Light and Light-Light Mesons

abstract:
  A common pattern of large orbital and radial excitations in heavy-light and
light-light mesons is demonstrated. Within a general potential model the Regge
slopes of the light degrees of freedom for these mesons are shown to be in the
ratio of two. The possibility of ``tower'' degeneracy occurs only with pure
scalar confinement.


title: Gauge-independent resummed gluon self-energy in hot QCD

abstract:
  The pinch technique (PT) is applied to obtain the gauge-independent resummed
gluon self-energy in a hot Yang-Mills gas. Calculation is performed at one-
loop level in linear gauges which preserve rotational invariance and the res
ummed propagators and vertices are used. The effective gluon self-energy, w
hich is obtained as the sum of the resummed gluon self-energy and the resumm ed
pinch contributions, is not only gauge-independent but also satisfies the
transversality relation. Using this gauge-independent effective gluon self-
energy, we calculate the damping rate for transverse gluons in the leading o
rder and show that the result coincides with the one obtained by Braaten and
Pisarski.


title: Decimation and survival at baryon violating gauntlet

abstract:
  We find that for second and weakly first order electroweak phase transition
(EWPT) the mere presence of non-zero Majorana masses for left-handed neutrinos
is sufficient to ensure the destruction of any existing baryon (lepton)
asymmetry. Even if the EWPT is strongly first order, a baryon asymmetry
generated before EWPT is seen to only barely survive, to the present, for
cosmologically interesting values of neutrino masses and mixing angles; the
scenario for survival being particularly bleak in the presence of an $SU(2)_R$
gauge symmetry at intermediate scales. Two sets of models, presented by us
earlier, that can avert the destruction of baryon asymmetry for any value of
neutrino masses and mixing angles and any order of EWPT are briefly discussed
and their relevance, in the light of latest observations, is pointed out.


title: A Supersymmetric Composite Model of Quarks and Leptons

abstract:
  We present a class of supersymmetric models with complete generations of
composite quarks and leptons using recent non-perturbative results for the low
energy dynamics of supersymmetric QCD. In these models, the quarks arise as
composite "mesons" and the leptons emerge as composite "baryons." The quark and
lepton flavor symmetries are linked at the preon level. Baryon number violation
is automatically suppressed by accidental symmetries. We give some speculations
on how this model might be made realistic.


title: The Electric Dipole Moment of the Muon in a Two Higgs Doublet Model

abstract:
  The electric dipole moment of the muon ($d_\mu$) is evaluated in a two Higgs
doublet model with a softly broken discrete symmetry. The leading contributions
from both one loop and two loop diagrams are considered. For $\tan\beta \equiv
|v_2|/|v_1|$ close to one, contributions from two loop diagrams involving the
$t$ quark and the $W$ boson dominate; while for $\tan\beta \agt 10$,
contributions from two loop diagrams involving the $b$ quark and the $\tau$
lepton are dominant. In these two regions, $d_\mu \approx (m_\mu/m_e) d_e$. For
$8 \agt \tan\beta \agt 4$, significant cancellation occurs among the
contributions from two loop diagrams and the one loop contribution dominates
for $\tan\beta \sim 7$. For $\tan\beta \agt 15$, the calculated $d_\mu$ can be
close to the reach of a recently proposed experiment at the Brookhaven National
Laboratory.


title:
Variation in polarization of high-energy $\gamma$-quanta traversing a
  bunch of polarized laser photons

abstract:
  The elastic light-light scattering below the threshold of the $e^+e^-$ pair
production leads to a variation in polarization of hard $\gamma$-quanta
traversing without loss a region where the laser light is focused. Equations
are obtained which determine the variation of Stokes parameters of
$\gamma$-quanta in this case, and their solutions are given. It is pointed out
that this effect can be observed in the experiment E-144 at SLAC. It should be
taken into account (and, perhaps, it can be used) in experiments at future
$\gamma \gamma$ colliders.


title: Status of chiral perturbation theory

abstract:
  A survey is made of semileptonic and nonleptonic kaon decays in the framework
of chiral perturbation theory. The emphasis is on what has been done rather
than how it was done. The theoretical predictions are compared with available
experimental results.


title: Constraints on the Wr mass and CP-violation in left-right models

abstract:
  We update the constraints on the right-handed $W_R$ gauge boson mass, mixing
angle $\zeta$ with the left-handed $W_L$ gauge boson, and other parameters in
general left-right symmetric models with different mechanisms of CP violation.
Constraints mostly independent of any assumption on the quark sector are
obtained from a re-analysis of muon decay data. Estimates of the left-right
hadronic matrix elements in the neutral kaon system and their uncertainties are
revised using large $N_c$ and Chiral Perturbation Theory arguments. With
explicitly given assumptions on the long-distance $(\Delta S=1)^2$
contributions to the $K_L-K_S$ mass difference, lower bounds on $M_{W_R}$ are
obtained. With the same assumptions, one also gets strong upper bounds from the
CP-violating parameter $\epsilon_K$, for most of the parameter space of
left-right models where the right-handed third family does not contribute in
CP-violating quantities.


title: Symposium Summary

abstract:
  The plenary presentations of the conference are summarised, highlighting some
aspects that were of particular interest and attempting to link a few of the
topics covered. Particular emphasis is placed on the problem of deep-inelastic
scattering and questions still to be answered with regard to the distribution
functions, strange-quark and gluon contributions, and the possible r\^ole of
orbital angular momentum. Passing reference is also made to some of the
parallel session presentations.


title: KNO scaling function of modified negative binomial distribution

abstract:
  We investigate the KNO scaling function of the modified negative binomial
distribution (MNBD), because this MNBD can explain the oscillating behaviors of
the cumulant moment observed in $e^+e^-$ annihilations and in hadronic
collisions. By using a straightforward method and the Poisson transform we
derive the KNO scaling function from the MNBD. The KNO form of experimental
data in $e^{+}e^{-}$ collisions and hadronic collisions are analyzed by the KNO
scaling function of the MNBD and that of the negative binomial distribution
(NBD). The KNO scaling function of the MNBD describes the data as well as that
of the NBD.


title:
On Possible Study of Quark-Pomeron Coupling Structure at the COMPASS
  spectrometer

abstract:
  We analyse the diffractive $Q \bar Q$ production and final jet kinematics in
polarized deep-inelastic lp scattering at $\sqrt{s}=20 GeV$. We show that this
reaction can be used in the new spectrometer of the COMPASS Collaboration at
CERN to study the quark-pomeron coupling structure.


title: Bound on R-parity violating couplings from nonleptonic B decay

abstract:
  The effective Hamiltonian for the R-parity violating couplings induced
nonleptonic decay $B^-\to K^-K^0$ is calculated including leading log QCD
corrections running from $m_{\tilde q}$, the mass of the up-type squark, to
$m_b$. Experimental upper limit of this decay is used to give the bound on the
R-parity violating couplings $\lambda''$.


title: Some Comments on Models of Hadronic Interactions at Air Shower Energies

abstract:
  Several models of minimum-bias hadronic interactions at ultra-high energy
that have been used for calculations of air showers share essential common
features. In this talk I review these common elements and discuss some
consequences. I concentrate on properties of hadron-nucleus interactions, and I
use mean depth of shower maximum as a function of primary energy to illustrate
my main points. I will contrast these models with models that use a more naive
treatment of hadronic interactions in nuclei but which have been successfully
used to interpret measurements of depth of shower maximum.


title: Neutrinoless Double Beta Decay and its "Inverse"

abstract:
  Recent considerations by these authors pointed out the attractive features
which a search for the exchange of heavy Majorana neutrinos could have for
solving the mass and the lepton number puzzles for all neutrinos, in TeV-level
electron-electron scattering. In the present note, we show that, contrary to
subsequently published arguments, non-observation of neutrinoless double beta
decay has, to date, no bearing on the promise of this important task for future
linear electron colliders.


title:
Automatic Computation Of Three-Loop Two-Point Functions In Large
  Momentum Expansion

abstract:
  We discuss the calculation of two-point three-loop functions with an
arbitrary number of massive propagators and one large external momentum. The
relevant subdiagrams are generated automatically. The resulting massless
two-point integrals and massive tadpoles are transformed on-line to
FORM-expressions ready to be used by existing FORM packages which calculate
them analytically. As an example we compute the quartic mass corrections to the
photon polarization function.


title:
Gluino Contribution to the 3-loop QCD beta function in the Minimal
  Supersymmetric Standard Model

abstract:
  We deduce the gluino contribution to the three-loop QCD \beta function within
the minimal supersymmetric Standard Model (MSSM) from its standard QCD
expression. The result is a first step in the computation of the full MSSM
three-loop \beta function. In addition, in the case of a light gluino it
provides the strong three-loop SUSY correction to the extrapolation of the
strong coupling constant from the low energy regime to the Z region and up to
the squark threshold.


title: CP Violation with Heavy Hadrons

abstract:
  I review several topics involving CP violation with heavy hadrons. In
particular, I discuss (i) Hyperons: CP violation in the decay $\Lambda^0 \to p
\pi^-$, (ii) Charm: indirect CP violation in the D^0 system, both within and
beyond the SM, and (iii) Beauty: indirect CP violation in the neutral B-meson
system beyond the SM.
  Talk presented at the 2nd International Conference on Hyperons, Charm and
Beauty Hadrons, Montr\'eal, Canada, August 1996.


title: On the position of a heavy Higgs pole

abstract:
  Higher loop calculations in the Higgs sector of the standard model at the
Higgs mass scale have shown that perturbation theory diverges very badly at
about 1 TeV in the on-shell renormalization scheme. The prediction of the
position of the Higgs pole in the complex s-plane becomes unreliable. We show
that in the pole renormalization scheme this appears to have much better
convergence properties, while showing good agreement with the on-shell scheme
over the validity range of the latter. This suggests that the pole scheme
should be preferable for phenomenological studies of heavy Higgs bosons. We
discuss whether this behaviour can be the result of a certain relation between
the on-shell mass and the pole mass at the nonperturbative level.


title:
Precision tests of the SM and higher order effects: the example of the
  effective mixing angle

abstract:
  The radiative corrections involved in the precise determination of the
electroweak mixing angle measured at the Z-peak are reviewed in detail, with
particular emphasis on the new calculation of two-loop heavy top effects. This
example serves as a brief pedagogical introduction to the problems and
techniques of higher order electroweak calculations.


title: Single spin asymmetry for the Drell-Yan process

abstract:
  We calculated the single spin asymmetries for the reaction
$P+P(\uparrow)\rightarrow l \overline{l}+X$ in the framework of twist-3 QCD for
HERA energies. The necessary imaginary phase is produced by the on-shell
contribution of the quark propagator, while the long distance part is analogous
to that providing the direct photon asymmetry calculated by J. Qiu and G.
Sterman. The asymmetry turns out to be generally of the order percent.


title: Leptonic Photon and Light Element Abundancies

abstract:
  In the framework of a model, in which a single leptonic photon $\gamma_l$ has
the same coupling to the doublets $\mu\nu_{\mu}$ and
$\bar{\tau}\bar{\nu}_{\tau}$, there is no cosmological bound on the strength of
this coupling.


title: Relativistic quantum mechanics in the einbein field formalism

abstract:
  The system of two relativistic particles with einbein fields is quantized as
a constrained system.A method of the introduction of the Newton--Wigner
collective coordinate is discussed in presence of different gauge fixing
conditions. Some arguments are involved in the favour of Lorents covariant
gauge fixing conditions.


title: Constraints on doubly charged Higgs interactions at linear collider

abstract:
  Production of a single doubly charged Higgs boson $Delta^{--}$ in polarized
$e^+e^-$ and $e^+\gamma$ collision modes of the linear collider have been
investigated. The mass range of $Delta^{--}$ to be probed extends up to the
collision energy. The diagonal lepton number violating Yukawa coupling $h_{ee}$
will be tested at least three orders of magnitude more strictly than in present
experiments.


title: Precise calculation of MW, sin^2 theta_MSbar, and sin^2 theta_eff

abstract:
  The two-loop O(g^4 mt^2/mw^2) corrections are incorporated in the theoretical
calculation of MW, sin^2 theta_MSbar(MZ), and sin^2 theta_eff, as functions of
MH. The analysis is carried out in a previously proposed MSbar formulation and
two novel on-shell resummation schemes. It is found that the inclusion of the
new effects sharply decreases the scheme and residual scale dependence of the
calculations. QCD corrections are incorporated in two different approaches.
Comparison with the world average of sin^2 theta_eff leads to MH= 127 +143 -71
GeV and MW= 80.367 +/- 0.048 GeV, with small variations among the six
calculations.


title: Exclusive semileptonic decays of heavy mesons in quark model

abstract:
  Semileptonic decays $D\to K,K^*,\pi,\rho$, $D_s\to \eta,\eta',\phi$, and
$B\to D,D^*,\pi,\rho$ are analyzed within the dispersion formulation of the
quark model. The form factors at timelike $q$ are derived by the analytical
continuation from spacelike $q$ in the form factors of the relativistic
light--cone quark model. The resulting double spectral representations allow a
direct calculation of the form factors in the timelike region. The results of
the model are shown to be in good agreement with all available experimental
data. From the analysis of the $B\to D,D^*$ decays we find $|V_{cb}|=0.037\pm
0.004$, and the $B\to\pi,\rho$ decays give $|V_{ub}|=0.004\pm 0.001$.


title:
Vacuum structure and effective potential at finite temperature: a
  variational approach

abstract:
  We compute the effective potential for $\phi^4$ theory with a squeezed
coherent state type of construct for the ground state. The method essentially
consists in optimising the basis at zero and finite temperatures. The gap
equation becomes identical to resumming the infinite series of daisy and super
daisy graphs while the effective potential includes multiloop effects and
agrees with that obtained through composite operator formalism at finite
temperature.


title: Colour deconfinement in hot and dense matter

abstract:
  We first introduce the conceptual basis of critical behaviour in strongly
interacting matter, with colour deconfinement as QCD analog of the
insulator-conductor transition and chiral symmetry restoration as special case
of the associated shift in the mass of the constituents. Next we summarize
quark-gluon plasma formation in finite temperature lattice QCD. We consider the
underlying symmetries and their spontaneous breaking/restoration in the
transition, as well as the resulting changes in thermodynamic behaviour.
Finally, we turn to the experimental study of strongly interacting matter by
high energy nuclear collisions, using charmonium production to probe the
confinement status of the produced primordial medium. Recent results from Pb-Pb
collisions at CERN may provide first evidence for colour deconfinement.


title:
Improved Spin Basis for Angular Correlation Studies in Single Top Quark
  Production at the Tevatron

abstract:
  We show in single top quark production that the spin of the top quark is
correlated with the direction of the d-type quark in the event. For single top
production in the W* channel, the d-type quark comes dominantly from the
antiproton at the Tevatron, whereas for the W-gluon fusion channel the
spectator jet is the d-type quark the majority of the time at this machine. Our
results are that 98% of the top quarks from the W* process have their spins in
the antiproton direction, and 96% of the top quarks in the W-gluon fusion
process have their spins in the spectator jet direction. We also compare with
the more traditional, but less effective, helicity basis. The direction of the
top quark spin is reflected in angular correlations in its decay products.


title: Neutrino Propagation Through a Fluctuating Sun (The Talk)

abstract:
  We summarize a general formulation of particle propagation in fluctuating
media, as applied to the description of neutrino propagation through the sun.
It contains the familiar MSW effective hamiltonian, plus corrections which
describe neutrino interactions with fluctuations in the medium. An estimate of
the size of these corrections for a simple model of solar fluctuations is made,
with the conclusion that they can produce surprisingly large effects since they
grow with the correlation length of the fluctuation. For MSW oscillations, the
leading effect for small fluctuations is to diminish the quality of the
resonance, making the suppression of the ${}^7$Be neutrinos an experimental
probe of fluctuations deep within the sun. Fluctuations can also provide an
energy-independent suppression factor of $\hf$, away from the resonant region,
even for small vacuum mixing angles. To be even potentially detectable, density
fluctuations must be correlated on scales of hundreds of kilometres, and have
amplitudes of a few percent or larger.


title: Almost maximally broken permutation symmetry for neutrino mass matrix

abstract:
  Assuming three light neutrinos are Majorana particles, we propose mass matrix
ansatz for the charged leptons and Majorana neutrinos with family symmetry
$S_{3} $ broken into $S_{1}$ and $S_{2}$, respectively. Each matrix has three
parameters, which are fixed by measured charged lepton masses, differences of
squared neutrino masses relevant to the solar and the atmospheric neutrino
puzzles, and the masses of three light Majorana neutrinos as a candidate for
hot dark matter with $\sum |m_{\nu}| \sim 6 eV$. The resulting neutrino mixing
is compatible with the data for the current upper limit, $ < m_{\nu_e} >_{th} <
0.8 eV$, of neutrino-less double beta decay experiments, and the current data
for various types of neutrino oscillation experiments. One solution of our
model predicts that $\nu_{\mu} \rightarrow \nu_{\tau}$ oscillation probability
is about $< 0.008$ with $\Delta m^{2} \sim 10^{-2} eV^2$, which may not be
accessible at CHORUS and other ongoing experiments.


title:
Exclusive photo- and electroproduction of mesons at large momentum
  transfer

abstract:
  We analyze the reactions gamma+p => M+B, with M B being either K+ Lambda, K+
Sigma0, or pi+ n, within perturbative QCD, allowing for diquarks as
quasi-elementary constituents of baryons. The diquark-model parameters and the
quark-diquark distribution amplitudes of the baryons are taken from previous
investigations of electromagnetic baryon form factors and Compton- scattering
off protons. Reasonable agreement with the few existing data at large momentum
transfer is achieved if the asymptotic form (c x (1-x)) is chosen for the meson
distribution amplitudes.


title:
Baryon Non-Conservation in Unified Theories, in the Light of
  Supersymmetry and Superstrings

abstract:
  The first part of this talk presents the general complexion of baryon and
lepton number non-conservation that may arise in the context of quark-lepton
unification. The second part presents the status of grand unification with and
without supersymmetry and spells out the characteristic proton decay modes,
which if seen, will clearly show supersymmetry. The main theme of this talk,
that follows next, pertains to two issues: (i) the need to remove the mismatch
between MSSM and string-unifications; and especially (ii) the need to resolve
naturally the problem of rapid proton decay, that generically arises in SUSY
unification. Seeking for a natural solution to this second problem, it is noted
that SUSY GUTS, including SUSY SO(10) and E_6, can at best accommodate
proton-stability by a suitable choice of the Higgs-multiplets and discrete
symmetries, but not really explain it, because they do not possess the desired
symmetries to suppress both d=4 and d=5 proton-decay operators. By contrast,
following a recent work, I argue that a class of string-solutions, possessing
three families, does possess the desired symmetries, which naturally safeguard
proton-stability from all potential dangers. They also permit neutrinos to have
desired light masses. This shows that, believing in supersymmetry, superstring
is needed just to understand why the proton is so stable.


title: Critical and Chaotic Behaviors of Quarks

abstract:
  The critical behavior of quarks undergoing phase transition to hadrons is
considered in the framework of the Ising model. It is found that spatial
fluctuations do not alter the F-scaling result obtained earlier in the
Ginzberg-Landau formalism. For the study of chaos a new measure must be found
for the quark-gluon system, for which the usual description appropriate for
classical nonlinear systems is inapplicable. It is shown that the entropy
indices $\mu_q$ which characterize the fluctuations of spatial patterns, are as
effective as the Lyapunov exponent in measuring chaos. When applied to the QCD
parton showers, it is found that the quark jets are more chaotic than gluon
jets. The analysis is highly appropriate for a quantitative treatment of the
erratic fluctuations of multiparticle production in leptonic, hadronic and
nuclear collision processes. It represents a step beyond the traditional
intermittency analysis.


title: Hadronic Decays and Lifetimes of B and D Mesons

abstract:
  We review recent experimental results on hadronic decays and lifetimes of
hadrons containing b and c quarks. We discuss charm counting and the
semileptonic branching fraction in B decays, the color suppressed amplitude in
B and D decay, and the search for gluonic penguins in B decay.


title:
Production of charged Higgs bosons of the Minimal Supersymmetric
  Standard Model in b-quark initiated processes at the Large Hadron Collider

abstract:
  We study integrated and differential rates for the production of charged
Higgs bosons $H^\pm$ of the Minimal Supersymmetric Standard Model via b-quark
initiated subprocesses in pp collisions at the Large Hadron Collider. In
detail, we compute cross sections and distributions of the reactions: $bU \to
bDH^+ \to bD\tau^+\nu_\tau\oplus C.C.$ and $bU \to bDH^+ \to bD t\bar b \to
bDb\bar b {jj}\oplus C.C.$, for a $H^\pm$ scalar in the intermediate (i.e.,
$M^\pm<m_t+m_b$) and heavy (i.e., $M^\pm>m_t+m_b$) mass range, respectively (U
and D represent generic u- and d-type light quarks). In the first case, a
detailed treatment of various possible backgrounds is also given.


title: Why Hybrid Meson Coupling to Two S-wave Mesons is Suppressed

abstract:
  We introduce strong interaction selection rules for the two-body decay and
production of hybrid and conventional mesons coupling to two S-wave hybrid or
conventional mesons. The rules arise from symmetrization in states in the limit
of non-relativistically moving quarks. The conditions under which hybrid
coupling to S-wave states is suppressed are determined by the rules, and the
nature of their breaking is indicated.