title:
Electroweak Radiative Corrections to W Boson Production in Hadronic
  Collisions

abstract:
  The O(\alpha) electroweak radiative corrections to the process pp, ppbar\to W
\to\ell^\pm\nu (\ell=e,\mu) are calculated. The O(\alpha) corrections can be
decomposed into separately gauge invariant contributions to the W boson
production and decay processes. Factorizing the collinear singularity
associated with initial state photon radiation into the parton distribution
functions, we find that initial state corrections have a significantly smaller
effect than final state radiative corrections. We study in detail the effect of
electroweak radiative corrections on a number of interesting observables: the W
transverse mass distribution, the W to Z transverse mass ratio, the charge
asymmetry of leptons in W\to\ell\nu decays, as well as the W production cross
section and the W to Z cross section ratio. We also investigate how
experimental lepton identification requirements change the effect of the
electroweak corrections.


title:
Phenomenological Profiles of the Inclusive Hadron Spectra in the Decay
  $B \to X_s \ell^+ \ell^-$

abstract:
  Hadron spectra and hadronic moments in the decay $B \to X_s \ell^+ \ell^-$
are calculated taking into account both the short-distance and long-distance
contributions in the decay amplitude using a Fermi motion (FM) model to
incorporate the $B$-meson wave-function effects. The measured branching ratios
for the inclusive decays $B \to X_s+ (J/\psi,\psi^\prime,...)\to X_s \ell^+
\ell^-$ are used to fix the normalization of the long-distance contribution.
The momentum distribution of the $J/\psi$ measured by the CLEO collaboration is
fitted in the FM model which is then used to calculate the hadronic spectra
from the resonant contribution also away from the $J/\psi$-resonance. We also
study the effect of various descriptions of the resonant and non-resonant
$c\bar{c}$ contributions in $B \to X_s \ell^+ \ell^-$ existing in the
literature on the hadron energy and invariant mass spectra, and in the
Forward-Backward asymmetry. Selective cuts on the hadron and dilepton invariant
masses can be used to reduce the $B\bar{B}$ background and resonant
contribution and, as an example, we work out the hadron spectra with the
experimental cuts used by the CLEO collaboration in searching for the decay $B
\to X_s \ell^+ \ell^-$. We show that data from the forthcoming B facilities
could be used effectively to measure the short-distance contribution in $B \to
X_s \ell^+ \ell^-$, enabling precise determination of the FM model and heavy
quark effective theory parameters $\lambda_1$ and $\bar{\Lambda}$.


title: Hyperons as collective excitations of chiral solitons

abstract:
  According to the large $N_C$ limit of QCD baryons are considered as soliton
solutions in effective mesons theories. While the classical solitons dwell in
the isospin subgroup of flavor SU(3) hyperon states are generated by canonical
quantization of the collective coordinates which describe the flavor
orientation of the soliton. The resulting Hamiltonian is diagonalized exactly
allowing one to discuss the dependence of various baryon properties on flavor
symmetry breaking. In particular axial charges, baryon magnetic moments and
radiative decay widths are considered.


title: Charge asymmetry of heavy quarks at hadron colliders

abstract:
  A sizeable difference in the differential production cross section of top and
antitop quarks, respectively, is predicted for hadronically produced heavy
quarks. It is of order $\alpha_s$ and arises from the interference between
charge odd and even amplitudes respectively. For the TEVATRON it amounts up to
15\% for the differential distribution in suitable chosen kinematical regions.
The resulting integrated forward-backward asymmetry of 4--5\% could be measured
in the next round of experiments. At the LHC the asymmetry can be studied by
selecting appropriately chosen kinematical regions. Furthermore, a slight
preference at LHC for centrally produced antitop is predicted, with top quarks
more abundant at large positive and negative rapidities.


title:
Bottom quark pole mass and $|V_{cb}|$ matrix element from $R(e^+e^-\to
  b\bar b)$ and $\Gamma_{sl}(b\to cl\nu_l)$ in the next-to-next-to-leading
  order

abstract:
  We present a consistent analysis of $\Upsilon$ sum rules and $B$-meson
semileptonic width in the next-to-next-to-leading order in the strong coupling
constant. The analysis is based on the analytical result for the heavy quark
vector current correlator near threshold in the second order in perturbative
and relativistic expansion around the nonrelativistic Coulomb approximation.


title: Quark Droplets in the NJL Mean Field

abstract:
  We study the conditions for the existence of stable quark matter in the
Nambu--Jona-Lasinio mean field at zero temperature and discuss its
interpretation.


title: Precise Prediction for the Mass of the Lightest Higgs Boson in the MSSM

abstract:
  The leading diagrammatic two-loop corrections are incorporated into the
prediction for the mass of the lightest Higgs boson, $\mh$, in the Minimal
Supersymmetric Standard Model (MSSM). The results, containing the complete
diagrammatic one-loop corrections, the new two-loop result and refinement terms
incorporating leading electroweak two-loop and higher-order QCD contributions,
are discussed and compared with results obtained by renormalization group
calculations. Good agreement is found in the case of vanishing mixing in the
scalar quark sector, while sizable deviations occur if squark mixing is taken
into account.


title: Extending the Higgs Boson Reach at the Upgraded Fermilab Tevatron

abstract:
  We study the observability for a Standard Model-like Higgs boson at an
upgraded Tevatron via the modes $p \bar p \to gg \to h \to \ww \to \ljj$ and
$\ll$. We find that with c. m. energy of 2 TeV and an integrated luminosity of
30 fb$^{-1}$ the signal may be observable for the mass range of $135 {\gev}
\lsim \mh \lsim 180$ GeV at a $3-5\sigma$ statistical level. We conclude that
the upgraded Tevatron may have the potential to detect a SM-like Higgs boson in
the mass range from the LEP2 reach to 180 GeV.


title:
The Super-Heat-Kernel Expansion and the Renormalization of the
  Pion-Nucleon Interaction

abstract:
  A recently proposed super-heat-kernel technique is applied to heavy baryon
chiral perturbation theory with two flavours. A previous result for the
one-loop divergences of the pion-nucleon system is confirmed, giving at the
same time an impressive demonstration of the efficiency of the new method. The
cumbersome and tedious calculations of the conventional approach are now
reduced to a few simple algebraic manipulations. The present computational
scheme is not restricted to chiral perturbation theory, but can easily be
applied or extended to any (in general non-renormalizable) theory with
boson-fermion interactions.


title: Solar Antineutrinos from Fluctuating Magnetic Fields at Kamiokande

abstract:
  We consider the effect of a strongly chaotic magnetic field at the narrow
bottom of the convective zone of the Sun together with resonant matter
oscillations on the production of electron Majorana antineutrinos. Even for
moderate levels of noise, we show that it is possible to obtain a small but
significant probability for $\nu_e\to \bar{\nu}_e$ conversions (1-3%) at the
energy range 2-10 MeV for large regions of the mixing parameter space while
still satisfying present (Super)-Kamiokande antineutrino bounds and observed
total rates. In the other hand it would be possible to obtain information about
the solar magnetic internal field if antineutrino bounds reach the 1% level and
a particle physics solution to the SNP is assumed. The mechanism presented here
has the advantage of being independent of the largely unknown magnetic profile
of the Sun and the intrinsic neutrino magnetic moment.


title: Supersymmetric one-loop corrections to the process e^+e^- to f fbar

abstract:
  Radiative one-loop corrections to fermion pair production in $e^+e^-$
annihilation are calculated in the Minimal Supersymmetric Standard Model
(MSSM). The size of the non-standard corrections is discussed for the process
e^+e^- to mu^+mu^- and e^+e^- to hadrons at LEP2 energies and for e^+e^- to t
tbar at a high energy e^+e^- collider. The relative difference between the
predictions of the MSSM and the Standard Model is typically below 10%.


title: Axions from string decay

abstract:
  We have studied numerically the evolution and decay of axion strings. These
global defects decay mainly by axion emission and thus contribute to the
cosmological axion density. The relative importance of this source relative to
misalignment production of axions depends on the spectrum. Radiation spectra
for various string loop configurations are presented. They support the
contention that the string decay contribution is of the same order of magnitude
as the contribution from misalignment.


title: Decay constant of eta-meson from QCD sum rule

abstract:
  Decay constant of eta-meson f is calculated on the basis of the QCD sum rule
method. An instanton contribution is taken into account. The result is f = 0.17
GeV.


title: The CP-Conserving Direction

abstract:
  A symmetry transformation is well defined in the case of an invariant theory,
being the corresponding operator undetermined otherwise. However, we show that,
even with CP violation, it is possible to determine the CP transformation by
separating the Lagrangian of the Standard Model in a CP-conserving and a
CP-violating part, in a unique way, making use of the empirically known quark
mixing hierarchy. To order \lambda^3 for the Bd-system, the CP-conserving
direction matches one of the sides of the (bd) unitarity triangle. We use this
determination to calculate the rephasing invariant parameter \epsilon, which
measures CP-mixing in the B0-B0bar system.


title: Resonant Bound State Production at e- e- Colliders

abstract:
  Observation of a sequence of resonances at an e-e- collider would suggest
bound states of strongly coupled constituents carrying lepton number. Obvious
candidates for these exotic constituents are leptoquarks and leptogluons. We
show that under reasonable assumptions, the existence of one leptogluon flavor
of appropriate mass can give rise to sizeable ``leptoglueball'' production
rates and observable resonance peaks. In contrast, one needs two leptoquark
flavors in order to produce the analogous ``leptoquarkonium'' states. Moreover,
cross-generational leptoquark couplings are necessary to give observable event
rates in many cases, and leptoquarkonium mass splittings are too small to
resolve with realistic beam energy resolutions.


title: $\Delta m^{2}$ Limits from $R(E_{\nu})$

abstract:
  A lower bound on $\Delta m^{2}$ for atmospheric neutrino oscillations can be
obtained from the global value of $R$ at a given energy. This bound may be more
reliable than one based on the observed isotropy. Some global values of $R$
imply an anisotropy in the neutrino flux that may, or may not be manifest in
the observed neutrino interactions. A limit of $\Delta m^{2}>0.0077$ eV$^{2}$
is easily obtained. Much higher mass scales are implied by the reported energy
independence and magnitude of $R$


title:
The 1.4 GeV J^PC = 1^-+ state as an interference of a non-resonant
  background and a resonance at 1.6 GeV

abstract:
  We investigate theoretical interpretations of the 1.4 GeV J^PC exotic
resonance reported by the E852 collaboration. A K-matrix analysis shows that
the 1.4 GeV enhancement in the E852 eta pi data can be understood as an
interference of a non-resonant Deck-type background and a resonance at 1.6 GeV.


title: Factorization for high-energy scattering

abstract:
  I demonstrate that the amplitude of the high-energy scattering can be
factorized in a product of two independent functional integrals over "fast" and
"slow" fields which interact by means of Wilson-line operators -- gauge factors
ordered along the straight lines.


title:
A New Regime for Dense String Networks in the One Scale Model with
  Friction

abstract:
  We examine the compatibility between the one scale model with friction for
the evolution of cosmic string networks with the Kibble mechanism for string
network formation during a second order phase transition. We find a regime
which connects (in a dramatically short time $\sim .1 t_c$) the dense string
network (small network scale $L\sim 1/T_c$) created by the Kibble
{\it{mechanism}} to the (dilute) Kibble {\it{regime}}(L\sim t^{3/4} in which
friction dominated strings remain till times $t_*\sim (M_P/T_c)^2t_c$. The
enormous loss of string length implied by this result is due to the continued
dissipative motion of the string network which follows from the one scale
model's identification of the typical curvature radius with the network scale
and the fact that the cosmological phase transition time $t_c\sim
M_{Planck}/T_c^2$ is much larger than the damping time scale $l_f\sim
T_c^2/T^3$. The significant implications for string mediated Baryogenisis are
also discussed briefly.


title:
Schroedinger cats, quantum slings and azimuthal effects in
  nucleus-nucleus collisions

abstract:
  Confinement of a chromodynamical string can result in specific effects in
scattering processes and multiparticle production. In particular, due to its
rotation secondary fragments of the splitting apart string can move like stones
thrown from a sling. That would be detected as the azimuthal asymmetry of
particle distributions in individual events. Thus we propose to explain the
elliptic flow observed in AA-collisions as a sling-effect. It can provide
information about confinement of quarks inside particles or binding forces in
nuclei. Nonclassical states of the created particles like the Schroedinger cats
are produced. Some classical and quantum-mechanical estimates of possible
effects are given. Experimental facts which can be used for their verification
are discussed.


title: New unified evolution equation

abstract:
  We propose a new unified evolution equation for parton distribution functions
appropriate for both large and small Bjorken variables $x$, which is an
improved version of the Ciafaloni-Catani-Fiorani-Marchesini equation. In this
new equation the cancellation of soft divergences between virtual and real
gluon emissions is explicit without introducing infrared cutoffs,
next-to-leading contributions to the Sudakov resummation can be included
systematically. It is shown that the new equation reduces to the
Dokshitzer-Gribov-Lipatov-Altarelli-Parisi equation at large $x$, to the
Balitsky-Fadin-Kuraev-Lipatov (BFKL) equation at small $x$, and to the modified
BFKL equations with a dependence on momentum transfer $Q$ and with unitarity,
if hard virtual gluon contributions and correction to strong rapidity ordering
are retained, respectively.


title:
The effect of the ultraviolet part of the gluon propagator on the heavy
  quark propagator

abstract:
  We revisit our recently proposed formalism for dealing with the heavy quark
limit of the quark Dyson-Schwinger equation. An ambiguity inherent in the
original version of method is identified and resolved. Our reanalysis
illustrates the importance of correctly accounting for the effect of hard gluon
momenta on the heavy quark self energy in the vicinity of the bare fermion mass
pole.


title:
An infrared singularity in the damping rate for longitudinal gluons in
  hot QCD

abstract:
  We calculate $\gamma_l(0)$, the damping rate for longitudinal on-shell gluons
with zero momentum in hot QCD using the hard-thermal-loop (htl) scheme. We find
it to be divergent in the infrared, which means that in this scheme
$\gamma_l(0)$ is different from $\gamma_t(0)$, the corresponding damping rate
for transverse gluons which is known to be finite. This result suggests that
the htl scheme is infrared sensitive and thus may need to be improved upon in
this sector. We discuss this issue after we present our calculation.


title:
Compact analytical form for a class of three-loop vacuum Feynman
  diagrams

abstract:
  We present compact, fully analytical expressions for singular parts of a
class of three-loop diagrams which cannot be factorized into lower-loop
integrals. As a result of the calculations we obtain the analytical expression
for the three-loop effective potential of the massive O(N) \phi^4 model
presented recently by J.-M.Chung and B.K.Chung, Phys.Rev. D56, 6508 (1997).


title: Signal for CP violation in $B^{\pm} \to P {\bar P} \pi^{\pm}$ decays

abstract:
  We analyze the partial rate asymmetry in $B^{\pm} \to P {\bar P} \pi^{\pm}$
decays ($ P = \pi^+, K ^+, \pi^0, \eta$) which results from the interference of
the nonresonant decay amplitude and the resonant amplitude for $B^{\pm} \to
\chi_{c0} \pi^{\pm} $ followed by the decay $\chi_{c0} \to P {\bar P} $. The CP
violating phase $\gamma$ can be extracted from the measured asymmetry. We find
that the partial rate asymmetry for $B^\pm \to \pi^+ \pi^- \pi^\pm$ is
$0.33~sin \gamma$, while for $B^\pm \to K^+ K^-\pi^\pm$ it amounts $0.45~ sin
\gamma$.


title: The field-theoretical approach to coherence in neutrino oscillations

abstract:
  We study the conditions for the existence of neutrino oscillations in the
field-theoretical approach which combines neutrino production and detection
processes in a single Feynman graph. The ``oscillating neutrino'' is
represented by an inner line of this graph where, due to the macroscopic
distance L between source and detector, the neutrino propagators for neutrinos
with definite mass are replaced by the projection operators unto the neutrino
states on mass shell. We use as a concrete model reaction the neutrino source
and detector as given in the LSND experiment and we carefully take into account
the finite lifetime of the stopped muons which provide the anti-muon neutrino
beam. We show that the field-theoretical approach provides a solid method to
locate all possible conditions and allows to separate unambiguously their
different origins. Some of these conditions are independent of L whereas others
state that coherence is lost when L exceeds a certain ``coherence length''.
Also it turns out that, at least in the concrete situation considered here, the
concept of neutrino wave packets is not supported by the field-theoretical
approach for realistic experimental conditions, i.e., the neutrino energy
spread is incoherent in origin.


title: Renormalons

abstract:
  A certain pattern of divergence of perturbative expansions in quantum field
theories, related to their small and large momentum behaviour, is known as
renormalons. We review formal and phenomenological aspects of renormalon
divergence. We first summarize what is known about ultraviolet and infrared
renormalons from an analysis of Feynman diagrams. Because infrared renormalons
probe large distances, they are closely connected with non-perturbative power
corrections in asymptotically free theories such as QCD. We discuss this aspect
of the renormalon phenomenon in various contexts, and in particular the
successes and failures of renormalon-inspired models of power corrections to
hard processes in QCD.


title: Light Mesons elm Form Factor and Running Coupling Effects

abstract:
  The pion and kaon electromagnetic form factors $F_{M}(Q^2)$ are calculated at
the leading order of pQCD using the running coupling constant method. In
computations dependence of the meson distribution amplitudes on the hard scale
$Q^2$ is taken into account. The Borel transform and resummed expression for
$F_{M}(Q^2)$ are found. The effect of the next-to-leading order term in
expansion of $\alpha_{S}(\lambda Q^2)$ in terms of $\alpha_{S}(Q^2)$ on the
pion form factor $F_{\pi}(Q^2)$ is discussed, comparison is made with the
infrared matching scheme's result.


title:
Bounds on R-parity violating SUSY Yukawa couplings from semileptonic
  decays of baryons

abstract:
  We consider tree-level corrections to hypercharge changing semileptonic
decays of certain baryons induced by a minimal supersymmetric standard model
with explicitly broken R-parity via $L$-violation. This study leads to a new
set of constraints on the products of couplings arising from the LQd$^c$
operator of the superpotential.


title:
Electroweak radiative corrections to polarized Moeller scattering at
  high energies

abstract:
  The cross section for $e^-e^- \to e^-e^-$ with arbitrary electron
polarizations is calculated within the Electroweak Standard Model for energies
large compared to the electron mass, including the complete virtual and
soft-photonic $O(\alpha)$ radiative corrections. The relevant analytical
results are listed, and a numerical evaluation is presented for the unpolarized
and polarized cross sections as well as for polarization asymmetries. The
relative weak corrections are typically of the order of 10%. At low energies,
the bulk of the corrections is due to the running of the electromagnetic
coupling constant. For left-handed electrons, at high energies the vertex and
box corrections involving virtual W bosons become very important. The
polarization asymmetry is considerably reduced by the weak radiative
corrections.


title: Final State Interaction Effects on $\gamma$ from $B \to D K$

abstract:
  The implications of a negligible annihilation contribution in $B \to D K$
decays are reanalyzed and are shown to lead to no new constraints on the weak
phase $\gamma$ from color-allowed $B^{\pm} \to D K^{\pm}$ decays. A test of
negligible annihilation is proposed in $B^+ \to D^+ K^0$ (or $B^+ \to D^+
K^{*0}$), and an application is presented in which $\gamma$ can be determined
from these processes (or corresponding $B \to D K^*$ decays) supplemented with
isospin-related neutral $B$ decays.


title:
Energy and Q^2 dependence of elastic vectormeson production and the
  proton structure function F_2

abstract:
  In the framework of the Model of the Stochastic Vacuum elastic hadron-hadron
scattering, photo- and electroproduction of vectormesons and also F_2(Q^2) can
be well described at center of mass energy approximately 20 GeV. The scattering
amplitude is derived by smearing the color dipole-dipole scattering, which is
calculated nonperturbatively in the Model of the Stochastic Vacuum, with
appropriate wavefunctions. For the considered processes the dipoles have
extensions in the range of hadron sizes. We now extend this idea to small
dipoles and high energies. The energy dependence is modeled in a
phenomenological way: we assume that there a two pomerons, the soft- and the
hard-pomeron, each being a simple pole in the complex angular plane. We couple
dipoles of hadronic size to the soft-pomeron and small dipoles to the
hard-pomeron. For small dipoles we take the perturbative gluon exchange into
account. By that way we obtain an energy dependent dipole-dipole scattering
amplitude which can be used for all the processes with the same parameters. We
show that this approach can describe in addition to all the low energy results
(20 GeV) also the HERA data for the considered processes in a large energy and
Q^2 range. Especially the right transition from the soft to the hard behavior
is observed.


title:
Single and Double Universal Seesaw Mechanisms with Universal Strength
  for Yukawa Couplings

abstract:
  Single and double universal seesaw mechanisms and the hypothesis of universal
strength for Yukawa couplings are applied to formulate a unified theory of
fermion mass spectrum in a model based on an extended Pati-Salam symmetry. Five
kinds of Higgs fields are postulated to mediate scalar interactions among
electroweak doublets of light fermions and electroweak singlets of heavy exotic
fermions with relative Yukawa coupling constants of exponential form. At the
first-order seesaw approximation, quasi-democratic mass matrices with equal
diagonal elements are derived for all charged fermion sectors and a diagonal
mass matrix is obtained for the neutrino sector under an additional ansatz.
Assuming the vacuum neutrino oscillation, the problems of solar and atmospheric
neutrino anomalies are investigated.


title: Multiparticle Production and Percolation of Strings

abstract:
  It is shown that the multiplicity distribution associated to self-shadowing
events satisfies an universal equation in terms of the minimum bias
distribution. The number of elementary collisions, basic in the structure of
any multiple scattering, is reduced if a collective effect like percolation of
strings takes place. The main consequences of the percolation are briefly
discussed.


title: High-Energy QCD as a Topological Field Theory

abstract:
  We propose an identification of the conformal field theory underlying
Lipatov's spin-chain model of high-energy scattering in perturbative QCD. It is
a twisted N=2 supersymmetric topological field theory, which arises as the
limiting case of the SL(2,R)/U(1) non-linear sigma model that also plays a role
in describing the Quantum Hall effect and black holes in string theory. The
doubly-infinite set of non-trivial integrals of motion of the high-energy
spin-chain model displayed by Faddeev and Korchemsky are identified as the
Cartan subalgebra of a W_{\infty} \otimes W_{\infty} bosonic sub-symmetry
possessed by this topological theory. The renormalization group and an analysis
of instanton perturbations yield some understanding why this particular
topological spin-chain model emerges in the high-energy limit, and provide a
new estimate of the asymptotic behaviour of multi-Reggeized-gluon exchange.


title: Higgs boson mass constraints from precision data and direct searches

abstract:
  Two of the nine measurements of $sin^{2}\theta^{lepton}_{eff}$, the effective
weak interaction mixing angle, are found to be in significant conflict with the
direct search limits for the Standard Model (SM) Higgs boson. Using a scale
factor method, analogous to one used by the Particle Data Group, we assess the
possible effect of these discrepancies on the SM fit of the Higgs boson mass.
The scale factor fits increase the value of $sin^{2}\theta^{lepton}_{eff}$ by
as much as two standard deviations. The central value of the Higgs boson mass
increases as much as a factor of two, to $\simeq 200$ GeV, and the 95%
confidence level upper limit increases to as much as 750 GeV. The scale factor
is based not simply on the discrepant measurements, as was the case in a
previous analysis, but on an aggregate goodness-of-fit confidence level for the
nine measurements and the limit. The method is generally applicable to fits in
which one or more of a collection of measurements are in conflict with a
physical boundary or limit. In the present context, the results suggest caution
in drawing conclusions about the Higgs boson mass from the existing data.


title: Sigma-terms in heavy baryon chiral perturbation theory revisited

abstract:
  The $\sigma$-terms are calculated at next-to-leading order in heavy baryon
chiral perturbation theory by employing a cutoff regularization. The results do
not depend on the cutoff value to the order we are working . The baryon masses
and $\sigma_{\pi N}(0)$ are used to perform a least-squares fit to the three
appearing low-energy constants and predictions for the two $KN$ $\sigma$-terms
and the strange contribution to the nucleon mass are made. The lack of
convergence in the chiral expansions of these quantities when regularized
dimensionally is overcome in the cutoff scheme. The $\sigma$-term shifts to the
pertinent Cheng-Dashen points are calculated. We also include the spin-3/2
decuplet in the effective theory.


title: Theories of Baryogenesis

abstract:
  These lectures provide a pedagogical review of the present status of theories
explaining the observed baryon asymmetry of the Universe. Particular emphasis
is given on GUT baryogenesis and electroweak baryogenesis. The key issues, the
unresolved problems and the very recent developments, such as GUT baryogenesis
during preheating, are explained. Some exercises (and their solution) are also
provided.


title:
Dyons as a source of CP and time invariance violation: electric dipole
  moments and K-meson decays

abstract:
  We consider a mechanism by which dyons (electrically charged magnetic
monopoles) can produce both a T- and P-odd (i.e. time reversal invariance and
parity violating) mixed polarizability beta [defined by Delta E = -beta E.B,
where Delta E is the energy change when electric (E) and magnetic (B) fields
are applied to a system] and a T- and P-odd interaction between two particles:
psi_1-bar gamma_5 psi_1 psi_2-bar psi_2, where the psi_i are electron and quark
spinors. The latter can create atomic and neutron electric dipole moments
(EDMs). From experimental bounds on these we find limits on the properties of
dyons. Our best limit, using the experimental limit for the EDM of the Tl atom,
is M |Q g (Q^2 - g^2)|^(-1/4) > 6 GeV, where M is the dyon mass and Q is the
electric and g the magnetic charge of the dyons. The contribution of dyons to
CP violation in K-meson decays is also estimated.


title:
Alternative mass shell renormalization for minimal supersymmetric Higgs
  sector

abstract:
  An Aoki-Denner form of the renormalization scheme is suggested for the
physical amplitudes in MSSM. The Higgs sector is reparameterized with the mass
of the CP odd scalar, and the mass of the heavy CP even one instead of
$tan\beta$ in our scheme. The counterterms of $tan\beta$ is fixed
perturbatively on mass shell just within
  Higgs sector. The counterterms of gauge-scalar mixings are defined with
Ward-Takahashi identit ies from scalar-scalar mixings. The effect of the
reparameterization is also probed on the radiative correction of the mass of
the lightest Higgs.


title: Universal Seesaw Mechanism with Universal Strength for Yukawa Couplings

abstract:
  Hypotheses of the universal seesaw mechanism and the {\it universal strength
for Yukawa couplings} are applied to explain one possible origin of
quasi-democratic mass matrices of a special type in a left-right symmetric
model with the gauge group $SU(3)_c\times SU(2)_L\times SU(2)_R\times U(1)$.
Two kinds of Higgs doublets are postulated to mediate scalar interactions
between the $i$-th generation of light fermion doublets and the $j$-th
generation of heavy fermion singlets with relative Yukawa coupling constants of
the exponential form $e^{i\phi_{ij}}$, where $\phi_{ij}$ are real phase
constants. The lowest seesaw approximation results effectively in self-adjoint
mass matrices which are quasi-democratic and have the same diagonal elements. A
set of values for the parameters $\phi_{ij}$ is found which reproduces the
present experimental data for the absolute values of the CKM matrix elements,
the Jarlskog parameter and the Wolfenstein parameters.


title: The Barbieri-Remiddi solution of the bound state problem in QED

abstract:
  We derive the so-called Barbieri-Remiddi solution of the Bethe-Salpeter
equation in QED in its general form and discuss its application to the bound
state energy spectrum.


title:
Corrections of order (Z\alpha)^6 m_e^2/m_\mu in the muonium fine
  structure

abstract:
  In the framework of the quasipotential method we calculate the contributions
of the kind (Z\alpha)^6m_e^2/m_\mu to the energy spectrum of the muonium n^3S_1
states. Numerical value of obtained correction for 2^3S_1-1^3S_1 muonium fine
structure interval is equal to 0.19 MHz.


title: Confinement and chiral symmetry breaking in heavy-light quark systems

abstract:
  Assuming a Gaussian approximation for the QCD gluodynamics, all the
nonperturbative physics can be encoded into two parameters: the gluon
correlation length $T_g$ and the gluon condensate $G_2$. These parameters are
sufficient in order to describe the heavy-heavy quark nonperturbative
interaction. In this work we adopt the same framework in order to study
heavy-light bound states in the non-recoil limit. Spontaneous chiral symmetry
breaking and a confining chiral non-invariant interaction emerge quite
naturally. The gap equation is solved and discussed. In particular a relation
between the light quark condensate and $T_g$ is derived. The energy spectrum
for the bound state equation is evaluated and commented.


title: Semileptonic B decays into excited charmed mesons from QCD sum rules

abstract:
  Exclusive semileptonic $B$ decays into excited charmed mesons are studied
with QCD sum rules in the leading order of heavy quark effective theory. Two
universal Isgur-Wise functions \tau and \zeta for semileptonic B decays into
four lowest lying excited $D$ mesons ($D_1$, $D_2^*$, $D'_0$, and $D'_1$) are
determined. The decay rates and branching ratios for these processes are
calculated.


title:
Unitarization of Gluon Distribution in the Doubly Logarithmic Regime at
  High Density

abstract:
  We analyze the general nonlinear evolution equations for multi gluon
correlators derived in hep-ph/9709432 by restricting ourselves to a double
logarithmic region. In this region our evolution equation becomes local in
transverse momentum space and amenable to simple analysis. It provides a
complete nonlinear generalization of the GLR equation. We find that the full
double log evolution at high density becomes strikingly different from its
linear doubly logarithmic DGLAP counterpart. An effective mass is induced by
the nonlinear corrections which at high densities slows down the evolution
considerably. We show that at small values of impact parameter the gluonic
density grows as a logarithm of energy. At higher values of impact parameter
the growth is faster, since the density of gluons is lower and nonlinearities
are less important.


title: Nonperturbative Corrections to One Gluon Exchange Quark Potentials

abstract:
  The leading nonperturbative QCD corrections to the one gluon exchange
quark-quark, quark-antiquark and $q \bar{q}$ pair-excitation potentials are
derived by using a covariant form of nonlocal two-quark and two-gluon vacuum
expectation values. Our numerical calculation indicates that the correction of
quark and gluon condensates to the quark-antiquark potential improves the heavy
quarkonium spectra to some degree.


title: Probing right-handed currents in B -> K* l+ l- transitions

abstract:
  We discuss a possibility to probe right-handed weak hadronic currents in rare
semileptonic b -> s transitions. It is shown that within models involving
right-handed as well as left-handed quark currents (LR models) one can expect a
strong enhancement of the right-handed K* production in B -> K* l+ l- decays
compared with models including only left-handed quark currents (SM, MSSM).
Hence an experimental study of the transverse asymmetry of the produced K*
mesons provides a clear test of the presence of the right-handed quark currents
and a possibiltity to discriminate between the MSSM and LR extentions of the
SM. At the same time, MSSM and LR models are found to yield qualitatively the
same type of deviations from the SM in the forward-backward and the
longitudinal lepton polarization asymmetries.


title:
Single- and multi-photon final states with missing energy at e+e-
  colliders

abstract:
  The search for new physics in single- and multi-photon final states with
large missing energy at LEP and future e^+ e^- colliders requires precise
predictions for the Standard Model irreducible background. While at LEP1 the
theoretical situation is under control, going to LEP2 (and beyond) some
improvements are necessary. To approach the aimed $O(1%)$ theoretical accuracy,
the tree-level matrix elements for the processes $e^+ e^- \to \nu \bar\nu
n\gamma$, with n=1,2,3, are exactly computed in the Standard Model, including
the possibility of anomalous couplings for single-photon production. Due to the
presence of observed photons in the final state, particular attention is paid
to the treatment of higher-order QED corrections. Comparisons with existing
calculations are shown and commented. An improved version of the event
generator NUNUGPV is presented.


title: Naturally light sterile neutrinos

abstract:
  A simple model to accomodate light sterile neutrinos naturally with large
mixing with the usual neutrinos has been proposed. The standard model gauge
group is extended to include an $SU(2)_S$ gauge symmetry. Heavy triplet higgs
scalars give small masses to the left-handed neutrinos, while a heavy doublet
higgs scalar give mixing with the sterile neutrinos of the same order of
magnitude. The neutrino mass matrix thus obtained can explain the solar
neutrino deficit, the atmospheric neutrino deficit, the LSND data and hot dark
matter. Lepton number is violated here through decays of the heavy triplet
higgs, which generates the lepton asymmetry of the universe, which in turn
generates a baryon asymmetry of the universe.


title: Chiral Disorder and Diffusion of Light Quarks in the QCD Vacuum

abstract:
  We give a pedagogical introduction to the concept that light quarks diffuse
in the QCD vacuum following the spontaneous breaking of chiral symmetry. By
analogy with disordered electrons in metals, we show that the diffusion
constant for light quarks in QCD is $D=2F_{\pi}^2/|\la\bar{q}q\to|$ which is
about 0.22 fm. We comment on the correspondence between the diffusive phase and
the chiral phase as described by chiral perturbation theory, as well as the
cross-over to the ergodic phase as described by random matrix theory. The
cross-over is identified with the Thouless energy $E_c=D/\sqrt{V_4}$ which is
the inverse diffusion time in an Euclidean four-volume $V_4$.


title: Status and perspectives of neutrino oscillation searches

abstract:
  The current status of neutrino oscillation searches with reactors and
accelerators is reviewed. An outlook, especially on future long baseline
neutrino oscillation projects, is given.


title: Top-Bottom Splitting in Technicolor with Composite Scalars

abstract:
  We present a model of dynamical electroweak symmetry breaking in which the
splitting between the top and bottom quark masses arises naturally. The W and Z
masses are produced by a minimal technicolor sector, the top quark mass is
given by the exchange of a weak-doublet technicolored scalar, and the other
quark and lepton masses are induced by the exchange of a weak-doublet
technicolor-singlet scalar. We show that, in the presence of the latter scalar,
the vacuum alignment is correct even in the case of SU(2) technicolor. The fit
of this model to the electroweak data gives an acceptable agreement
(chi-squared = 28 for 20 degrees of freedom). The mass hierarchy between the
standard fermions other than top can also be explained in terms of the
hierarchy of squared-masses of some additional scalars. We discuss various
possibilities for the compositeness of the scalars introduced here.


title: Higher Fock states and power counting in exclusive charmonium decays

abstract:
  The role of higher Fock-state contributions to exclusive charmonium decays
will be discussed. It will be argued that the J/Psi (Psi') decays into
baryon-antibaryon pairs are dominated by the valence Fock-state contributions.
P-wave charmonium decays, on the other hand, receive strong contributions from
the c cbar g Fock states since the valence Fock-state contributions are
suppressed in these reactions. Numerical results for the decay widths of J/Psi
(Psi') into baryon-antibaryon and chi(J) into pairs of pseudoscalar mesons will
be also presented and compared to data.


title: The Diquark Model for Exclusive Reactions

abstract:
  The present status of the diquark model for exclusive reactions at moderately
large momentum transfer is reviewed. That model is a variant of the
Brodsky-Lepage approach in which diquarks are considered as quasi-elementary
constituents of baryons. Recent applications of the diquark model, relevant to
high energy physics with electromagnetic probes, are discussed.


title:
The Generalized Non-forward BFKL Equation and the ``Bootstrap''
  Condition for the Gluon Reggeization in the NLLA

abstract:
  The generalization of the BFKL equation for the case of non-forward
scattering is considered. The kernel of the generalized equation in the
next-to-leading approximation is expressed in terms of the gluon Regge
trajectory and the effective vertices for particle production in Reggeon
collisions. The ``bootstrap'' equations for the gluon Reggeization are
presented.


title: Cosmological and astrophysical aspects of finite-density QCD

abstract:
  The different phases of QCD at finite temperature and density lead to
interesting effects in cosmology and astrophysics. In this work I review some
aspects of the cosmological QCD transition and of astrophysics at high baryon
density.


title: pi+pi- Atom in Chiral Theories

abstract:
  We review the existing theoretical approaches to the study of the observables
of hadronic atoms. In the relativistic perturbative approach based on the
Bethe-Salpeter equation and Chiral Perturbation Theory we derive the general
expression for the pi+pi- atom lifetime. The lowest-order correction to the
relativistic Deser-type formula for the atom width is predicted to be 6.1\pm
3.1 %.


title:
Atmospheric neutrinos, long-baseline neutrino beams and the precise
  measurement of the neutrino oscillation parameters

abstract:
  Measurements of atmospheric neutrinos by Super-Kamiokande an other detectors
have given evidence for the existence of neutrino oscillations with large
mixing and $\Delta m^2$ in the range 10^{-3}-10^{-2} eV^2. In this work we
discuss critically some of the possible experimental strategies to confirm this
result and determine more accurately the neutrino oscillation parameters. A
possible method is the development of long-baseline accelerator neutrino beams.
The accelerator beams can have higher intensity and higher average energy than
the atmospheric flux, and if (\nu_\mu \leftrightarrow \nu_\tau) oscillations
are indeed the cause of the atmospheric neutrino anomaly, they can produce a
measurable rate of $\tau$ leptons for most (but not all) of the values of the
oscillation parameters that are a solution to the atmospheric data. On the
other hand measurements of atmospheric neutrinos with large statistics and/or
better experimental resolutions, can also provide convincing evidence for
oscillations, thanks to unambiguous detectable effects on the energy, zenith
angle and L/E_\nu distributions of the events. The study of these effects can
provide a precise determination of the oscillations parameters. The range of
L/E_\nu available for atmospheric neutrinos is much larger than in
long-baseline accelerator experiments, and the sensitivity extends to lower
values of \Delta m^2.


title: Helioseismological constraint on solar axion emission

abstract:
  Helioseismological sound-speed profiles severely constrain possible
deviations from standard solar models, allowing us to derive new limits on
anomalous solar energy losses by the Primakoff emission of axions. For an
axion-photon coupling $g_{a\gamma} < 5 x 10^(-10) GeV^(-1)$ the solar model is
almost indistinguishable from the standard case, while $g_{a\gamma} > 10 x
10^(-10) GeV^(-1)$ is probably excluded, corresponding to an axion luminosity
of about $0.20 L_(sun)$. This constraint on $g_{a\gamma}$ is much weaker than
the well-known globular-cluster limit, but about a factor of 3 more restrictive
than previous solar limits. Our result is primarily of interest to the large
number of current or proposed search experiments for solar axions because our
limit defines the maximum g_{a\gamma}$ for which it is self-consistent to use a
standard solar model to calculate the axion luminosity.


title: Duality of Reggeon Interactions in QCD

abstract:
  The duality symmetry of the hamiltonian and integrals of motion for reggeon
interactions in the multi-colour QCD is formulated as an integral equation for
the wave function of compound states of reggeized gluons, which together with
the property of holomorphic factorization allows one to reduce the Odderon
problem in QCD to the solution of the one-dimensional Schroedinger equation.


title: Can FCNC transition $c\to ul^+l^-$ be seen in $D\to Vl^+l^-$ decays?

abstract:
  The decays $D\to Vl^+l^-$ present in principle the opportunity to observe the
short distance FCNC transition $c\to ul^+l^-$, which is sensitive to the
physics beyond the Standard Model. We analyze the $D \to V l^+ l^- $ decays
within the Standard Model, where in addition to the short distance dynamics
also the long distance dynamics is present. The short distance contribution due
to $c\to ul^+l^-$ transition, which is present only in the Cabibbo suppressed
decays, is found to be three orders of magnitude smaller than the long distance
contribution. The branching ratios well above $10^{-7}$ for Cabibbo suppressed
decays could signal new physics. The most frequent decays are the Cabibbo
allowed decays $D_s^+\to\rho^+\mu^+\mu^-$ and $D^0\to\bar K^{*0}\mu^+\mu^-$,
which are expected at the branching ratios of $3\cdot 10^{-5}$ and $1.7\cdot
10^{-6}$, respectively. These rates are not much lower than the present
experimental upper limit.


title:
Physics Implications of Flat Directions in Free Fermionic Superstring
  Models I: Mass Spectrum and Couplings

abstract:
  From the "top-down" approach we investigate physics implications of the class
of D- and F- flat directions formed from non-Abelian singlets which are proven
flat to all orders in the nonrenormalizable superpotential, for a prototype
quasi-realistic free fermionic string model with the standard model gauge group
and three families (CHL5). These flat directions have at least an additional
U(1)' unbroken at the string scale. For each flat direction, the complete set
of effective mass terms and effective trilinear superpotential terms in the
observable sector are computed to all orders in the VEV's of the fields in the
flat direction. The "string selection-rules" disallow a large number of
couplings allowed by gauge invariance, resulting in a massless spectrum with a
large number of exotics, in most cases excluded by experiment, thus signifying
a generic flaw of these models. Nevertheless, the resulting trilinear couplings
of the massless spectrum possess a number of interesting features which we
analyse for two representative flat directions: for the fermion texture;
baryon- and lepton-number violating couplings; R-parity breaking; non-canonical
mu terms; and the possibility of electroweak and intermediate scale symmetry
breaking scenarios for U(1)'. The gauge coupling predictions are obtained in
the electroweak scale case. Fermion masses possess t-b and tau-mu universality,
with the string scale Yukawa couplings g and $g/\sqrt{2}$, respectively.
Fermion textures are present for certain flat directions, but only in the
down-quark sector. Baryon- and lepton- number violating couplings can trigger
proton-decay, $N-{\bar N}$ oscillations, leptoquark interactions and R-parity
violation, leading to the absence of a stable LSP.


title: W^+- H^-+ Associated Production at the Large Hadron Collider

abstract:
  We study the production of a charged Higgs boson in association with a W
boson at the CERN Large Hadron Collider in the context of the minimal
supersymmetric extension of the standard model. This production mechanism is
particularly promising if the charged Higgs boson is too heavy to be generated
by top-quark decay. We compare the contributions due to b b-bar annihilation at
the tree level and gg fusion, which proceeds at one loop. Apart from the total
cross section, we also consider distributions in transverse momentum and
rapidity. We also assess the viability of W^+- H^-+ associated production at
the Fermilab Tevatron after the installation of the Main Injector and the
Recycler.


title:
LEP Constraints on Neutralino Relic Densities, and the Fate of Higgsino
  Dark Matter

abstract:
  We examine the current state of neutralino dark matter and consider how the
LEP constraints on the Minimal Supersymmetric Standard Model parameters are
squeezing the available dark matter regions. We also show how cosmological
constraints augment bounds coming from collider searches to further constrain
the MSSM parameter space.


title: Topological $R^4$ Inflation

abstract:
  We consider the possibility that higher-curvature corrections could drive
inflation after the compactification to four dimensions. Assuming that the
low-energy limit of the fundamental theory is eleven-dimensional supergravity
to the lowest order, including curvature corrections and taking the descent
from eleven dimensions to four via an intermediate five-dimensional theory, as
favored by recent considerations of unification at some scale around $\sim
10^{16}$ GeV, we may obtain a simple model of inflation in four dimensions. The
effective degrees of freedom are two scalar fields and the metric. The scalars
arise as the large five-dimensional modulus and the self-interacting conformal
mode of the metric. The effective potential has a local maximum in addition to
the more usual minimum. However, the potential is quite flat at the top, and
admits topological inflation. We show that the model can resolve cosmological
problems and provide a mechanism for structure formation with very little fine
tuning.


title: Constraints on Electron-quark Contact Interactions

abstract:
  In this talk, I summarize a global analysis on electron-quark contact
interactions using the updated NC DIS data at HERA, Drell-yan production at the
Tevatron, total hadronic cross sections at LEP, atomic parity violation
measurement, low energy $e$-nucleon scattering data, and the $\nu$-nucleon
scattering data. The global data do not show any evidence for contact
interactions. Thus, we obtain limits of 8--15 TeV on the compositeness scale,
which are significantly better than those published by each individual
experiment.


title:
Some Astrophysical Implications of Experimentally Favored Neutrino
  Masses and Mixings

abstract:
  Positive evidence for neutrino oscillations is mounting from the solar and
atmospheric neutrino anomalies and the LSND experiment. Accordingly, the
neutrino mass differences appear to lie in the sub-eV range and at least some
of the mixing angles appear to be large. We explore some of the consequences of
this picture for supernova (SN) physics and cosmology. In particuler, we
discuss if a conflict between the solar vacuum solution and the SN 1987A signal
can be avoided, and the role of future cosmic microwave background measurements
to reveal the presence of a cosmological hot dark matter component.


title:
Bound q\bar q Systems in the Framework of the Different Versions of the
  3-Dimensional Reductions of the Bethe-Salpeter Equation

abstract:
  Bound q\bar q systems are studied in the framework of different 3-dimensional
relativistic equations derived from the Bethe-Salpeter equation with the
instantaneous kernel in the momentum space. Except the Salpeter equation, all
these equations have a correct one-body limit when one of the constituent quark
masses tends to infinity. The spin structure of the confining qq interaction
potential is taken in the form $x\gamma_{1}^{0}\gamma_{2}^{0}+(1-x)I_{1}I_{2}$,
with $0\leq x \leq 1$. At first stage, the one-gluon-exchange potential is
neglected and the confining potential is taken in the oscillator form. For the
systems (u\bar s), (c\bar u), (c\bar s) and (u\bar u), (s\bar s) a comparative
qualitative analysis of these equations is carried out for different values of
the mixing parameter x and the confining potential strength parameter. We
investigate: 1)the existence/nonexistence of stable solutions of these
equations; 2) the parameter dependence of the general structure of the meson
mass spectum and leptonic decay constants of pseudoscalar and vector mesons. It
is demonstrated that none of the 3-dimensional equations considered in the
present paper does simultaneously describe even general qualitative features of
the whole mass spectrum of q\bar q systems. At the same time, these versions
give an acceptable description of the meson leptonic decay characteristics.


title:
Electron Self-Energy in Strong Magnetic Field: Summation of Double
  Logarithmic Terms

abstract:
  We study the electron self--energy in a strong magnetic field when the
parameter \eta\equiv (\alpha/2\pi) \ln^2 (eB/m^2_0) \sim 1 and explore the
transition between the perturbative regime \eta<<1 and the nonperturbative
massless QED regime \eta>>1 where chiral symmetry is broken spontaneously and
electrons acquire the dynamically induced mass.


title: A light leptophobic Z' in polarized hadronic collisions

abstract:
  Theoretical and phenomenological arguments are in favor of an elusive new
neutral vector boson Z' with a relatively low mass, chiral couplings to
ordinary quarks and whose couplings to ordinary leptons are suppressed
(leptophobia). We point out that this new particle could induce some parity
violating spin asymmetries which could be measured soon at the Brookhaven
Relativistic Heavy Ion Collider (RHIC), running part of the time as a polarized
hadronic collider.


title: Hard diffraction at HERA in the dipole model of BFKL dynamics

abstract:
  Using the QCD dipole picture of the hard BFKL pomeron, we derive the general
expressions of the elastic and inelastic components of the proton diffractive
structure functions. We obtain a good 7 parameter fit (including a secondary
reggeon contribution) to data taken at HERA by the H1 and ZEUS collaborations.
The main characteristic features of the model in reproducing the data are
discussed, namely the effective pomeron intercept, the scaling violations and
the beta dependence. A difference obtained in the separate H1 and ZEUS fits
leads us to analyse directly the differences between both measurements.
Predictions on R, the ratio of longitudinal to transverse photon cross sections
are performed and lead to very large values at high beta and large virtuality Q
which may lead to a discrimination between models.


title:
$m_b(m_Z)$ from jet production at the $Z$ peak in the Cambridge
  algorithm

abstract:
  We consider the production of heavy quark jets at the $Z$-pole at the
next-to-leading order (NLO) using the {\it Cambridge jet-algorithm}. We study
the effects of the quark mass in two- and three-jet observables and the
uncertainty due to unknown higher order corrections as well as due to
fragmentation. We found that the three-jet observable has remarkably small NLO
corrections, which are stable with respect to the change of the renormalization
scale, when expressed in terms of the {\it running quark mass} at the
$m_Z$-scale. The size of the hadronization uncertainty for this observable
remains reasonably small and is very stable with respect to changes in the jet
resolution parameter $y_c$.


title: Thouless Energy and Correlations of QCD Dirac Eigenvalues

abstract:
  Eigenvalues and eigenfunctions of the QCD Dirac operator are studied for an
instanton liquid partition function. We find that for energy differences
$\delta E$ below an energy scale $E_c$, identified as the Thouless energy, the
eigenvalue correlations are given by Random Matrix Theory. The value of $E_c$
shows a weak volume dependence for eigenvalues near zero and is consistent with
a scaling of $E_c \sim 1/L^2$ in the bulk of the spectrum in agreement with
estimates from chiral perturbation theory, that $E_c/\Delta \approx F_\pi^2
L^2/\pi$ (with average level spacing $\Delta$). For $\delta E> E_c$ the number
variance shows a linear dependence. For the wave functions we find a small
nonzero multifractality index.


title:
Gauge Mediated Supersymmetry Breaking and Spontaneous CP Violation as a
  Solution to the Strong CP Problem

abstract:
  The origin of CP violation is a major mystery, especially in relation to the
strong CP problem. CP being a spontaneously broken symmetry could provide an
elegant solution. However, such models have difficulty making themselves
compatible with low-energy supersymmetry, which is popularly accepted as the
solution to the hierarchy problem. We demonstrate that a certain class of low
scale supersymmetric ``Nelson-Barr'' type models can solve the strong and
supersymmetric CP problems while at the same time generating sufficient weak CP
violation in the $K^{0}-\bar{K}^{0}$ system. Gauge-mediated supersymmetry
breaking is used to provide the needed squark mass degeneracies and $A$-term
proportionalities; though that proves to be still insufficient for a generic
Nelson-Barr model. The workable model we consider here, essentially a
supersymmetric version of the aspon model, has the Nelson-Barr mass texture
enforced by a U(1) gauge symmetry, broken at the TeV scale. The resulting model
is predictive with rich phenomenology soon to be available. Feasibility of the
model considered is established by a detailed renormalization group studies.


title: Renormalon Ambiguities in NRQCD Operator Matrix Elements

abstract:
  We analyze the renormalon ambiguities that appear in factorization formulas
in QCD. Our analysis contains a simple argument that the ambiguities in the
short-distance coefficients and operator matrix elements are artifacts of
dimensional-regularization factorization schemes and are absent in cutoff
schemes. We also present a method for computing the renormalon ambiguities in
operator matrix elements and apply it to a computation of the ambiguities in
the matrix elements that appear in the NRQCD factorization formulas for the
annihilation decays of S-wave quarkonia. Our results, combined with those of
Braaten and Chen for the short-distance coefficients, provide an explicit
demonstration that the ambiguities cancel in the physical decay rates. In
addition, we analyze the renormalon ambiguities in the Gremm-Kapustin relation
and in various definitions of the heavy-quark mass.


title: A Toy Model for Open Inflation

abstract:
  The open inflation scenario based on the theory of bubble formation in the
models of a single scalar field suffered from a fatal defect. In all the
versions of this scenario known so far, the Coleman-De Luccia instantons
describing the creation of an open universe did not exist. We propose a simple
one-field model where the CDL instanton does exist and the open inflation
scenario can be realized.


title: On power corrections in the dispersive approach

abstract:
  Power corrections in QCD (both conventional and unconventional ones arising
from the ultraviolet region) are discussed within the infrared finite
coupling-dispersive approach. It is shown how power corrections in Minkowskian
quantities can be derived from the corresponding ones in associated Euclidean
quantities through analyticity, allowing a parametrization in term of the
Euclidean coupling and a renormalon-free perturbative expansion. It is argued
that one should in general expect coefficients functions computed in the true
non-perturbative vacuum to differ from the standard perturbative ones, even
without assuming new physics. A phenomenology of $1/Q^2$ terms arising from
eventual new physics of ultraviolet origin is also set-up. Models for
non-perturbative contributions to the (universal) QCD coupling are suggested.
Issues of renormalization scheme dependence are commented upon.


title: Exclusive Nonleptonic Decays of Heavy Mesons in QCD

abstract:
  We use operator product expansion and QCD light-cone sum rules to estimate
the amplitude of the decay $B \to J/\psi K $ taking into account leading
nonfactorizable contributions. The result is very similar to the estimate
obtained earlier from a four-point QCD sum rule. We discuss applications of
this method to other nonleptonic $B$ decay modes.


title:
A new method for extracting the weak phase gamma from B ---> D K(*)
  decays

abstract:
  A new method to extract the weak phase $\gamma$ is suggested by exploiting B
---> D K^{(*)} decay modes that are not Cabibbo suppressed, using the isospin
relations, and ignoring the annihilation diagram as usual. Assuming $3 \times
10^8 B\bar{B}$ pair at $B$ factories, one can determine $\gamma$ with
$3-\sigma$ accuracy for 80^o < $\gamma$ < 150^o using B ---> D K modes and for
50^o < $\gamma$ < 170^o using B ---> D K^* modes.


title: Off-diagonal parton distributions and their evolution

abstract:
  We construct off-diagonal parton distributions defined on the interval 0 < X
< 1 starting from the off-forward distributions defined by Ji. We emphasize the
particular role played by the symmetry relations in the "ERBL-like" region. We
find the evolution equations for the off-diagonal distributions which conserve
these symmetries. We present numerical results of the evolution, and verify
that the analytic asymptotic forms of the parton distributions are reproduced.
We also compare the constructed off-diagonal distributions with the non-forward
distributions defined by Radyushkin and comment on the singularity structure of
the basic amplitude written in terms of the off-diagonal distributions.


title: Three-Loop Effective Potential of O(N) $\phi^4$ Theory

abstract:
  The three-loop effective potential of the massless O(N) $\phi^4$ theory is
calculated analytically using techniques of dimensional regularization. We see
a complete agreement between our result and Jackiw's result obtained only up to
two-loop order using a different regularization (cutoff regularization) method,
but the same renormalization conditions. For an easy check of the mutual
cancellation of all the dangerous pole terms in each loop order, we give the
$\epsilon$-expanded loop integrals in full detail.


title: Two-Color QCD and Aharonov-Bohm Fluxes

abstract:
  We investigate the effects of several Abelian Aharonov-Bohm fluxes $\phi$ on
the Euclidean Dirac spectrum of light quarks in QCD with two colors. A
quantitative change in the quark return probability is caused by the fluxes,
resulting into a change of the spectral correlations. These changes are
controlled by a universal function of $\sigma_L \phi^2$ where $\sigma_L$ is the
pertinent Ohmic conductance. The quark return probability is sensitive to
Abelian flux-disorder but not to $Z_2$ flux-disorder in the ergodic and
diffusive regime, and may be used as a probe for the nature of the confining
fields in the QCD vacuum.


title: Kaon electroweak form factors in the light-front quark model

abstract:
  We investigate the form factors and decay rates for the semileptonic decays
of the kaon($K_{l3})$ using the light-front quark model. The form factors
$f_{\pm}(q^{2})$ are calculated in $q^{+}=0$ frame and analytically continued
to the time-like region, $q^{2}>0$. Our numerical results for the physical
observables, $f_{-}/f_{+}|_{q^{2}=m^{2}_{l}}=-0.38$, $\lambda_{+}=0.025$(the
slope of $f_{+}$ at $q^{2}=m^{2}_{l}$), $\Gamma(K^{0}_{e3})=(7.30\pm
0.12)\times10^{6}s^{-1}$, and
$\Gamma(K^{0}_{\mu3})=(4.57\pm0.07)\times10^{6}s^{-1}$ are quite comparable
with the experimental data and other theoretical model calculations. The
non-valence contributions from $q^{+}\neq 0$ frame are also estimated.


title:
The Neutron and the Lepton EDMs in MSSM, Large CP violating Phases, and
  the Cancellation Mechanism

abstract:
  An analysis of the electric dipole moment (EDM) of the neutron and of the
leptons in the minimal supersymmetric standard model (MSSM) with the most
general allowed set of CP violating phases without generational mixing is
given. The analysis includes the contributions from the gluino, the chargino
and the neutralino exchanges to the electric dipole operator, the chromoelectic
dipole operator, and the CP violating purely gluonic dimension six operator. It
is found that the EDMs depend only on certain combination of the CP phases. The
independent set of such phases is classified. The analysis of the EDMs given
here provides the framework for the exploration of the effects of large CP
violating phases on low energy phenomena such as the search for supersymmetry
at colliders, and in the analyses of dark matter consistent with the
experimental limits on EDMs via the mechanism of internal cancellations.


title: Phenomenology with Supersymmetric Flipped SU(6)

abstract:
  The supersymmetric flipped $SU(6)\times U(1)$ gauge symmetry can arise
through compactification of the ten dimensional $E_8\times E_8$ superstring
theory. We show how realistic phenomenology can emerge from this theory by
supplementing it with the symmetry ${\cal R}\times {\cal U}(1)$, where ${\cal
R}$ denotes a discrete `R'-symmetry. The well-known doublet-triplet splitting
problem is resolved to `all orders' via the pseudo-Goldstone mechanism, and the
GUT scale arises from an interplay of the Planck and supersymmetry breaking
scales.
  The symmetry ${\cal R}\times {\cal U}(1)$ is also important for understanding
the fermion mass hierarchies as well as the magnitudes of the CKM matrix
elements. Furthermore, the well known MSSM parameter $\tan \beta $ is estimated
to be of order unity, while the proton lifetime ($\tau_p\sim
10^2\tau_{pSU(5)}$) is consistent with observations. Depending on some
parameters, $p\to K\mu^+ $ can be the dominant decay mode.
  Finally, the observed solar and atmospheric neutrino `anomalies' require us
to introduce a `sterile' neutrino state. Remarkably, the ${\cal R}\times {\cal
U}(1)$ symmetry protects it from becoming heavy, so that maximal angle
$\nu_{\mu}$ oscillations into a sterile state can explain the atmospheric
anomaly, while the solar neutrino puzzle is resolved via the small angle
$\nu_e-\nu_{\tau}$ MSW oscillations. The existence of some ($\sim 15 - 20% $ of
critical energy density) neutrino hot dark matter is also predicted.


title: Beyond the Standard Embedding in M-Theory on S^1/Z_2

abstract:
  In this paper we discuss compactifications of M-theory to four dimensions on
X \times S^1/Z_2, in which nonstandard embeddings in the E_8 \times E_8 vacuum
gauge bundle are considered. At the level of the effective field theory
description of Horava and Witten, this provides a natural extension of well
known results at weak coupling, to strongly coupled E_8 \times E_8 heterotic
strings. As an application of our results, we discuss models which exhibit an
anomalous U(1)_A symmetry in four dimensions, and show how this emerges from
the reduction of the d = 11 toplogical term C \wedge G \wedge G, and how it is
consistent with d = 4 anomaly cancellation in M-theory. As a further
application of nonstandard embeddings, we show how it is possible to obtain an
inverse hierarchy of gauge couplings, where the observable sector is more
strongly coupled than the hidden one. The basic construction and
phenomenological viability of these scenarios is demonstrated.


title:
Dynamical Generation of Linear $\sigma$ model SU(3) Lagrangian and Meson
  Nonet Mixing

abstract:
  This paper is the SU(3) extension of the dynamically generated SU(2) linear
$\sigma$ model Lagrangian worked out previously using dimensional
regularization. After discussing the quark-level Goldberger-Treiman relations
for SU(3) and the related gap equations, we dynamically generate the meson
cubic and quartic couplings. This also constrains the meson-quark coupling
constant to $g=2\pi/\sqrt3$ and determines the SU(3) scalar meson masses in a
Nambu-Jona-Lasinio fashion. Finally we dynamically induce the U(3) pseudoscalar
and scalar mixing angles in a manner compatible with data.


title: Regularizing the quark-level $\sigma$ model

abstract:
  We show that the finite difference, $-i\pi^2 m^2$, between quadratic and
logarithmic divergent integrals $\int d^4p[m^2(p^2-m^2)^{-2}-(p^2-m^2)^{-1}]$,
as encountered in the linear $\sigma$ model, is in fact regularization
independent.


title: Nucleon structure functions from a chiral soliton

abstract:
  We study nucleon structure functions within the bosonized version of the
Nambu-Jona-Lasinio (NJL) model in which the nucleon emerges as the soliton in
the chiral field. Upon boosting to the infinite momentum frame and performing
the $q^2$-evolution in the context of the Gottfried sum rule for electron
nucleon scattering we determine the intrinsic scale $\mu^2$ of the NJL chiral
soliton. We also compute the leading twist contributions of the polarized
structure functions $g_1$ and $g_2$. We compare these model predictions with
experiment by evolving them from $\mu^2$ to the scale where the data are taken.
Analogously we analyze the chiral-odd structure functions $h_T$ and $h_L$.
Finally we generalize the treatment to flavor SU(3).


title:
Direct CP Violation in Angular Distribution of $B\to J/\psi K^{*}$
  Decays

abstract:
  We show that the study of certain observables in the angular distribution in
$B\to J/\psi K^*$ provide clear test for CP vioaltion beyond the Standard
Model. These observables vanish in SM, but in models beyond SM some of them can
be large enough to be measured at B factories.


title:
Electromagnetic Transition Form Factor of Pseudoscalar Meson and
  $\eta-\eta'$ Mixing

abstract:
  The electromagnetic transition form factors of $\eta$ and $\eta'$ are
calculated in the light-cone perturbation theory. We show that it is unreliable
to determine the \eta-\etap'$ mixing angle without any additional normalization
conditions other than their decay widthes to two photons. The possible
intrinsic $c\bar{c}$ component in the flavor singlet is investigated. The heavy
quark pair has distinct properties from the light ones in electromagnetic
transition processes of pseudoscalar mesons. It is possible to explore the size
of $c\bar{c}$ component and our numerical results disfavor a large portion of
$c\bar{c}$ component.


title: Systematics of single superpartners production at leptonic colliders

abstract:
  We examine the effects of the lepton number violating R parity odd
interactions, $\lambda_{ijk} $, on single production of fermion (charginos and
neutralinos) and scalar (sleptons and sneutrinos) superpartners at leptonic
colliders for center of mass energies up to $500GeV - 1TeV$. The probability
amplitudes for all the five relevant $2 \to 2$ body processes and the decays
branching ratios for the produced superpartners are calculated at tree level. A
semi-quantitative discussion is developed within a supergravity model assuming
grand unification of gauge interactions and universal (flavor independent) soft
supersymmetry breaking parameters at the unification scale. The predictions
obtained for the total and partial rates show that the single production
reactions have a good potential of observability at NLC (Next Linear Colliders)
energies. For values of the R parity violating coupling constant, $\lambda
_{ijk}= 0.05$, close to the current bounds, the $\tilde \chi^{\pm, 0}$
reactions could probe all the relevant intervals for $\tan \beta$ and $m_0$ and
broad regions of the parameter space for $\mu$ and $M_2$, while the $\tilde \nu
$ and $\tilde l $ productions could probe sneutrinos and sleptons masses up to
the kinematical limits. Using the hypothesis of a single dominant R parity
violating coupling constant, a Monte Carlo events simulation for the $ \tilde
\chi^{\pm, 0} $ reactions is employed to deduce some characteristic final
states dynamical distributions.


title: Electroweak phase transition in a strong magnetic field

abstract:
  Phase transitions induced by high temperatures and strong magnetic fields are
investigated in the Standard model. The consistent effective potential
including the one-loop and ring diagram contributions is calculated and
investigated for the wide range of the fields, temperatures and Higgs boson
mass $m_H$. All other particles - fermions and bosons - are taken into account
with actual values of their masses. This effective potential is real at
sufficiently high temperatures . It is shown that symmetry restoration is a
first type phase transition for $m_H < 70 $ Gev . For heavier Higgs particles
and the field strengths $H > 0.1 \cdot 10^{24} G $ the local electroweak
minimum could not be realized at all. Hence, the upper limit on the Higgs mass
as well as the limit on the field strengths in the phase transition epoch
follow.


title: Atmospheric \nu_\mu Deficit from Decoherence

abstract:
  The simplest explanation for the observed deficit of atmospheric muon
neutrinos is that they have oscillated into tau or sterile neutrinos with an
oscillation length of the order of the Earth diameter. In order to confirm this
hypothesis, all other possible explanations should be ruled out. We propose
that a viable alternative hypothesis is that the muon neutrino deficit is
caused by flavor sampling events that result in a loss of coherence. The
coherence length of the muon neutrinos is expected to be approximately one
Earth diameter. We give predictions and experimental tests of this scenario.


title: Modelling Sonoluminescence

abstract:
  In single-bubble sonoluminescence, a bubble trapped by a sound wave in a
flask of liquid is forced to expand and contract; exactly once per cycle, the
bubble emits a very sharp ($< 50 ps$) pulse of visible light. This is a robust
phenomenon observable to the naked eye, yet the mechanism whereby the light is
produced is not well understood. One model that has been proposed is that the
light is "vacuum radiation" generated by the coupling of the electromagnetic
fields to the surface of the bubble. In this paper, we simulate vacuum
radiation by solving Maxwell's equations with an additional term that couples
the field to the bubble's motion. We show that, in the static case originally
considered by Casimir, we reproduce Casimir's result. In a simple purely
time-dependent example, we find that an instability occurs and the pulse of
radiation grows exponentially. In the more realistic case of
spherically-symmetric bubble motion, we again find exponential growth in the
context of a small-radius approximation.


title:
Saturation Effects in Deep Inelastic Scattering at low $Q^2$ and its
  Implications on Diffraction

abstract:
  We present a model based on the concept of saturation for small $Q^2$ and
small $x$. With only three parameters we achieve a good description of all Deep
Inelastic Scattering data below $x=0.01$. This includes a consistent treatment
of charm and a successful extrapolation into the photoproduction regime. The
same model leads to a roughly constant ratio of diffractive and inclusive cross
section.


title: Reflections on the Strong CP Problem

abstract:
  I discuss how anomalies affect classical symmetries and how, in turn, the
non-trivial nature of the gauge theory vacuum makes these quantum corrections
troublesome. Although no solution seems in sight for the cosmological constant
problem, I examine three possible approaches to the strong CP problem involving
vacuum dynamics, an additional chiral symmetry, and the possibility of
spontaneous CP or P breaking. All of these "solutions" have their own problems
and suggest that, at a deep level, we do not understand the nature of CP
violation. Nevertheless, it remains extremely important to search for
experimental signals predicted by these theoretical "solutions", like invisible
axions.


title:
Higgs Production in Charged Current Six Fermion Processes at Future
  $e^+e^-$ Colliders

abstract:
  We study higgs physics at future $e^+e^-$ colliders taking into account the
full set of Feynman diagrams for six fermion final states, which are produced
for higgs masses near or above the two $W$'s threshold. In particular we
examine events where one isolated lepton or two isolated leptons of different
flavours signal the presence of two $\rm W^*$'s. For these charged current
processes, a detailed analysis of the relevance of irreducible and QCD
background shows that appropriate cuts are generally sufficient to deal with it
in the case of reconstructed or missing higgs mass distributions. These latter
are however affected by a non negligible distortion and shift of the maximum.


title: Discrete and Global Symmetries in Particle Physics

abstract:
  I begin these lectures by examining the transformation properties of quantum
fields under the discrete symmetries of Parity, P, Charge Conjugation, C, and
Time Reversal, T. With these results in hand, I then show how the structure of
the Standard Model helps explain the conservation/violation of these symmetries
in various sectors of the theory. This discussion is also used to give a
qualitative proof of the CPT Theorem, and some of the stringent tests of this
theorem in the neutral Kaon sector are reviewed. In the second part of these
lectures, global symmetries are examined. Here, after the distinction between
Wigner-Weyl and Nambu-Goldstone realizations of these symmetries is explained,
a discussion is given of the various, approximate or real, global symmetries of
the Standard Model. Particular attention is paid to the role that chiral
anomalies play in altering the classical symmetry patterns of the Standard
Model. To understand the differences between anomaly effects in QCD and those
in the electroweak theory, a discussion of the nature of the vacuum structure
of gauge theories is presented. This naturally raises the issue of the strong
CP problem, and I present a brief discussion of the chiral solution to this
problem and of its ramifications for astrophysics and cosmology. I also touch
briefly on possible constraints on, and prospects for, having real
Nambu-Goldstone bosons in nature, concentrating specifically on the simplest
example of Majorons. I end these lectures by discussing the compatibility of
having global symmetry in the presence of gravitational interactions. Although
these interactions, in general, produces small corrections, they can alter
significantly the Nambu-Goldstone sector of theories.


title: Large Neutrino Flavor Mixings and Lepton Mass Matrices

abstract:
  Recent atmospheric neutrino data at Super-Kamiokande suggest the near-maximal
flavor mixing. Models for the lepton mass matrix, which give the near-maximal
flavor mixing, are discussed in this report. Mass matrix models are classified
according to the mechanism providing the large flavor mixing, and those are
reviewed briefly. "Naturalness" of the mass matrix is also discussed in order
to select the neutrino mass matrix. Details of the mass matrix with the $S_3$
flavor symmetry are presented.


title:
Further Study on Possible Violation of CP, T and CPT Symmetries in the
  $K^0$-$\bar{K^0}$ System --- Remarks and Results ---

abstract:
  We demonstrate how one may identify or constrain possible violation of $CP$,
$T$ and $CPT$ symmetries in the $K^0$-$\bar{K^0}$ system in a way as
phenomenological and comprehensive as possibie. For this purpose, we first
introduce parameters which represent violation of these symmetries in mixing
parameters and decay amplitudes in a well-defined way. After discussing some
characteristics of these parameters, we derive formulae which relate them to
the experimentally measured quantities. We then carry out a numerical analysis
with the help of the Bell-Steinberger relation to derive constraints to these
violating parameters from available experimental data. Finally, we compare our
parametrization and procedure of analysis with those employed in the recent
literature.


title: One-Pion Charm Baryon Transitions in a Relativistic Three-Quark Model

abstract:
  We study one-pion transitions between charm baryon states in the framework of
a relativistic three-quark model. We calculate the charm baryon-pion coupling
factors that govern the S-wave, P-wave and D-wave one-pion transitions from the
s-wave and the lowest lying p-wave charm baryon states down to the s-wave charm
baryon states. For these we obtain: g_{\Sigma_c\Lambda_c\pi}=8.88 GeV^{-1},
f_{\Lambda_{c1}\Sigma_c\pi}=0.52 and f_{\Lambda_{c1}^*\Sigma_c\pi}=21.5
GeV^{-2}. We compare our rate predictions for the one-pion transitions with
experimental results.


title: A superweak solution of the Strong CP Problem

abstract:
  A non-axion solution to the Strong CP Problem is proposed that works even in
the context of gravity-mediated supersymmetry breaking. Both
$\epsilon'/\epsilon$ and indirect CP violation in the $B-\bar{B}$ are predicted
to be unobservably small. $\mu \longrightarrow e \gamma$ is predicted to arise,
typically, with branching ration $3 \times 10^{-12}$. A new source of dark
matter is also predicted in the model.


title: Evolution of a Network of Cosmic String Loops

abstract:
  We discuss and summarise the predictions of a model for the non-equilibrium
evolution of a network of cosmic strings initially containing {\em only loops}
and {\em no infinite strings}. The results are of interest given recent work
highlighting the problems with structure formation from the standard cosmic
string scenario.


title: TeV-scale GUTs

abstract:
  In this talk, we summarize our recent proposal for lowering the scale of
grand unification to the TeV range though the appearance of extra spacetime
dimensions. Particular emphasis is placed on the perturbativity and
predictivity of our scenario, as well as its sensitivity to unification-scale
effects.
  (Proceedings of invited talks given by KRD at PASCOS '98; by TG at the
European Network Meeting ``From the Planck Scale to the Electroweak Scale'';
and by KRD and TG at SUSY '98.)


title: The Warm Inflation Early Universe

abstract: A general overview is given of the warm inflation scenario.


title: Periodic Euclidean Solutions of SU(2)-Higgs Theory

abstract:
  We examine periodic, spherically symmetric, classical solutions of
SU(2)-Higgs theory in four-dimensional Euclidean space. Classical perturbation
theory is used to construct periodic time-dependent solutions in the
neighborhood of the static sphaleron. The behavior of the action, as a function
of period, changes character depending on the value of the Higgs mass. The
required pattern of bifurcations of solutions as a function of Higgs mass is
examined, and implications for the temperature dependence of the baryon number
violation rate in the Standard Model are discussed.


title: Do hep neutrinos affect the solar neutrino energy spectrum?

abstract:
  If the low energy cross section for 3He + p goes to 4He + e + nu_e, the `hep'
reaction, is > 20 times larger than the best (but uncertain) theoretical
estimates, then this reaction could significantly influence the electron energy
spectrum produced by solar neutrino interactions and measured in the
SuperKamiokande, SNO, and ICARUS experiments. We compare predicted energy
spectra for different assumed hep fluxes and different neutrino oscillation
scenarios with the observed SuperKamiokande spectrum. The spectra with enhanced
hep contributions provide better fits to the SuperKamiokande data.


title: Developments in Supersymmetry Phenomenology

abstract:
  We survey strategies generally employed for SUSY discovery at colliders and
then discuss how these may have to be altered for SUSY searches at the Tevatron
if $\tan\beta$ is large. We also discuss the reach of the Tevatron and the LHC
in gauge-mediated SUSY breaking scenarios, assuming that the NLSP decays into
photons. Finally, we briefly recapitulate measurements (which serve to guide us
to the underlying theory) that might be possible at future colliders if
supersymmetry is discovered.


title: Next-to-Leading BFKL

abstract:
  The representation of the total cross section at high energy $\sqrt s$ in the
next-to-leading $\ln s$ approximation is given with definition of the impact
factors and explicit expression for the BFKL kernel. The estimate of the
Pomeron intercept and the next-to-leading contributions to anomalous dimensions
near $j=1$ are presented.


title: BFKL News

abstract:
  I discuss radiative corrections to the BFKL equation for high energy cross
sections in perturbative QCD. Due to the gluon Reggeization in the
next-to-leading $\ln s$ approximation, the form of the BFKL equation remains
unchanged and the corrections to the BFKL kernel are expressed in terms of the
two-loop contribution to the gluon Regge trajectory, the one-loop correction to
the Reggeon-Reggeon-gluon vertex and the contributions from two-gluon and
quark-antiquark production in Reggeon-Reggeon collisions. I present the results
of the calculation of the BFKL kernel in the next-to leading logarithmic
approximation, the estimate of the Pomeron shift and the next-to-leading
contribution to the anomalous dimensions of twist-2 operators near $j=1$.


title:
Spin effects in high-energy proton-proton scattering within a diquark
  model

abstract:
  We study $pp$ scattering at high energies and moderately large momentum
transfer, using a model in which the proton is viewed as being composed of a
quark and a diquark. We show that this model leads to single and double spin
transverse asymmetries which are neither small nor vanish at high energies.


title: Three steps in intranuclear cascading

abstract:
  Between the initial excitation of nucleons by the passing throughout each
other and the final cascading of newly created hadrons there should be
considered one more step. We call it the second step cascading process. It acts
as an interaction of wounded nucleon from one nucleus with another nucleon from
the same nucleus. This mechanism leads to the significant increase on the
inelasticity for nuclei collisions without changing the hadron-hadron
interaction characteristics.


title: Nuclei cross sections in Extensive Air Showers

abstract:
  Cross sections for proton inelastic collision with different nuclei are
described within the Glauber approximation. The significant difference between
approximate ``Glauber'' formula and exact calculations with geometrical scaling
assumption is shown for very high energy cross section calculations. According
to obtained results values of proton-proton cross section reported by the Akeno
and Fly's Eye experimental groups are about 10 % overestimated.


title:
Comparisons of New Jet Clustering Algorithms for Hadron-Hadron
  Collisions

abstract:
  We investigate a modification of the $k_\perp$-clustering jet algorithm for
hadron-hadron collisions, analogous to the ``Cambridge'' algorithm recently
proposed for $e^+e^-$ annihilation, in which pairs of objects that are close in
angle are combined preferentially. This has the effect of building jets from
the inside out, with the aim of reducing the amount of the underlying event
incorporated into them. We also investigate a second modification that involves
using a new separation measure. Monte Carlo studies suggest that the standard
$k_\perp$ algorithm performs as well as either of these modified algorithms
with respect to hadronization corrections and reconstruction of the mass of a
Higgs boson decaying to $b\bar b$.


title: Demonstration of the double Q^2-rescaling model

abstract:
  In this paper we have demonstrated the double Q^2-rescaling model (DQ^2RM) of
parton distribution functions of nucleon bounded in nucleus. With different
x-region of l-A deep inelastic scattering process we take different approach:
in high x-region (0.1\le x\le 0.7) we use the distorted QCD vacuum model which
resulted from topologically multi -connected domain vacuum structure of
nucleus; in low x-region (10^{-4}\le x\le10^{-3}) we adopt the Glauber
(Mueller) multi- scattering formula for gluon coherently rescattering in
nucleus. From these two approach we justified the rescaling parton distribution
functions in bound nucleon are in agreement well with those we got from DQ^2RM,
thus the validity for this phenomenologically model are demonstrated.


title:
A Dynamical Origin of the Mass Hierarchy among Neutrinos, Charged
  Leptons, and Quarks

abstract:
  We propose a dynamical mass-generation scenario which naturally realizes the
mass hierarchy among the neutrinos, charged leptons and quarks, where the mass
is dominated by the self-mass induced through the anomalous (i.e. non-minimal)
gauge interactions.


title: On the Extensive Air Shower density spectrum

abstract:
  In search for new methods of determining the primary energy spectrum of
Cosmic Rays, the attention was paid to the density spectrum measurement. New
methods available at present warrant an accurateness of conclusions derived
from the density spectrum measurements. The general statement about the change
of the spectral index of the charged particle density spectrum is confirmed
very clearly. Results concerning the shower size and primary energy spectra are
also presented and discussed. Interesting future prospects for applications of
the density spectrum method are proposed.


title: Vector Boson decays of the Higgs Boson

abstract:
  We derive the width of the Higgs boson into vector bosons. General formulas
are derived both for the on-shell decay H -> VV as well for the off-shell
decays, H -> V^* V and H -> V^* V^*, where V=\gamma,W,Z. For the off-shell
decays the width of the decaying vector boson is properly included. The
formulas are valid both for the Standard Model as well as for arbitrary
extensions. As an example we study in detail the gauge-invariant effective
Lagrangian models where we can have sizable enhancements over the Standard
Model that could be observed at LEP.


title: Vector meson dominance and the rho meson

abstract:
  We discuss the properties of vector mesons, in particular the rho^0, in the
context of the Hidden Local Symmetry (HLS) model. This provides a unified
framework to study several aspects of the low energy QCD sector. Firstly, we
show that in the HLS model the physical photon is massless, without requiring
off field diagonalization. We then demonstrate the equivalence of HLS and the
two existing representations of vector meson dominance, VMD1 and VMD2, at both
tree level and one loop order. Finally the S matrix pole position is shown to
provide a model and process independent means of specifying the rho mass and
width, in contrast to the real axis prescription currently used in the Particle
Data Group tables.


title:
Jet Cross Sections in gamma^*-gamma Scattering at e+e- Colliders in NLO
  QCD

abstract:
  Recent results from NLO QCD calculations for inclusive jet cross sections in
gamma^*-gamma scattering at e+e- colliders, especially for LEP, are reported.
The virtuality Q^2 of the virtual photon is non-zero and can be unlimited
large. The virtuality of the second photon is zero and the spectrum is
calculated with the Weizs"acker-Williams approximation. Four components of the
cross sections have to be distinguished, involving direct and resolved real and
virtual photon contributions. Since Q^2 is non-zero, the virtual photon
structure function is needed to calculate the contributions involving a
resolved virtual photon.


title: Phenomenology of Scalar Mesons

abstract:
  A separable potential model of three coupled channels (pion-pion,
kaon-antikaon and an effective four pion) has been constructed and applied in
the analysis of the isoscalar S-wave pion-pion and kaon-antikaon phase shifts
and inelasticities .A relatively narrow scalar resonance of mass 1400-1460 MeV
has been found. This resonance is consistent with the recent CERN observation
of an eventual scalar glueball at 1500 MeV. Other resonances at lower energies
like a wide sigma meson and a narrow f0(980) have been confirmed.


title:
Light-cone path integral approach to the Landau-Pomeranchuk-Migdal
  effect

abstract:
  A new rigorous light-cone path integral approach to the
Landau-Pomeranchuk-Migdal effect in QED and QCD is discussed. The rate of
photon (gluon) radiation by an electron (quark) in a medium is expressed
through the Green's function of a two-dimensional Schrodinger equation with an
imaginary potential. In QED this potential is proportional to the dipole cross
section for scattering of e+e- pair off an atom, in QCD it is proportional to
the cross section of interaction of the color singlet quark-antiquark-gluon
system with a medium constituent. In QED our predictions agree well with the
photon spectrum measured recently at SLAC for 25 GeV electrons. In QCD for a
sufficiently energetic quark produced inside a medium we predict the radiative
energy loss proportional L^{2}, where L is the distance passed by the quark in
the medium. It has a weak dependence on the initial quark energy. The L^{2}
dependence transforms into L^{1} as the quark energy decreases. We also give
new formulas for nuclear shadowing in hard reactions.


title: Is there screwiness at the end of the QCD cascades?

abstract:
  We discuss what happens at the end of the QCD cascades. We show that, with
just a few reasonable assumptions, the emission of soft gluons is constrained
to produce an ordered field in the form of a helix. We describe how to modify
the Lund fragmentation scheme in order to fragment such a field. Our modified
fragmentation scheme yields results which are consistent with current
experimental measurements, but predicts at least one signature which should be
observable.


title:
Discussion about the orthopositronium decay rate and analysis of some
  $O(\alpha^2)$ contributions

abstract:
  I consider the problem of the evaluation of the orthopositronium decay rate,
including second order radiative corrections. I present a brief theoretical
discussion of this problem and a review of the results available in literature,
and, then, I analyze some $O(\alpha^2)$ annihilation-type contributions,
recently computed.


title: Neutrino Mass Difference Induced Oscillations in Observed Muon Decays

abstract:
  The recent real time KARMEN anomaly for the electron neutrino counting rates
(obtained from stopped muon decays) is analyzed by employing a neutrino flavor
rotation model in which the muon neutrino is in a superposition of only two
mass eigenstates. On the basis of experimental electron neutrino counting
oscillations, we find a neutrino mass splitting $|m_2^2-m_1^2|=(0.22\pm
0.02)(eV/c^2)^2$ and a flavor rotation angle $\phi =0.34\pm 0.10$, both within
a 95% confidence interval.


title: Primordial Black Hole Formation in Supergravity

abstract:
  We study a double inflation model (a preinflation + a new inflation) in
supergravity and discuss the formation of primordial black holes which may be
identified with massive compact halo objects (MACHOs) observed in the halo of
our galaxy. The preinflation drives an inflaton for the new inflation close to
the origin through supergravity effects and the new inflation naturally occurs.
If the total e-fold number of the new inflation is smaller than $\sim 60$, both
inflations produce cosmologically relevant density fluctuations. If the
coherent inflaton oscillation after the preinflation continues until the
beginning of the new inflation, density fluctuations on small cosmological
scales can be set suitably large to produce black holes MACHOs of masses $\sim
1 M_{\odot}$ in a wide region of parameter space in the double inflation model.


title: Mass and Width of a Heavy Higgs Boson

abstract:
  The gauge dependence of the Higgs-boson mass and width in the on-shell scheme
of renormalization is studied in the heavy-Higgs-boson approximation. The
corresponding expansions in the pole scheme are analyzed adopting three
frequently employed parametrizations. The convergence properties and other
theoretical features of the on-shell and pole expansions, as well as their
relative merits, are discussed.


title: Charmonium suppression from purely geometrical effects

abstract:
  The extend to which geometrical effects contribute to the production and
suppression of the $J/\psi$ and $q\bar{q}$ minijet pairs in general is
investigated for high energy heavy ion collisions at SPS, RHIC and LHC
energies. For the energy range under investigation, the geometrical effects
referred to are shadowing and anti-shadowing, respectively. Due to those
effects, the parton distributions in nuclei deviate from the naive
extrapolation from the free nucleon result; $f_{A}\neq A f_{N}$. The strength
of the shadowing/anti-shadowing effect increases with the mass number. The
consequences of gluonic shadowing effects for the $x_F$ distribution of
$J/\psi$'s at $\sqrt s =20$ GeV, $\sqrt s =200$ GeV and $\sqrt s =6$ TeV are
calculated for some relevant combinations of nuclei, as well as the $p_T$
distribution of minijets at midrapidity for $N_f=4$ in the final state.


title:
Could we learn more about HERA high $Q^2$ anomaly from LEP200 and
  TEVATRON? R-parity violation scenario

abstract:
  The excess of high $Q^2$ events at HERA reported in the early 1997 by H1 and
ZEUS collaborations has become the subject of extensive studies in the
framework of several models related to new physics. Here we concentrate on the
most promising, from our point of view, model describing HERA anomaly. We
update our previous analysis and take into account new HERA statistics of the
1997 year. HERA events are considered within the R-parity broken SUSY model for
a specific scenario with several non-zero couplings. R-parity broken SUSY with
several non-zero couplings could explain both high $Q^2 e^+ + jets$ and $\mu^+
+ jets$ observed at HERA. The consequence of such a particular scenario is the
excess of high $Q^2$ di- or tri-jet events at HERA. The relation of this
scenario for LEP and TEVATRON colliders is considered. This study shows that if
a squark resonance does take place at HERA, supersymmetry with broken R-parity
can be revealed at either LEP200 or TEVATRON in the near future.


title:
The Callan-Symanzik equation of the electroweak Standard Model and its
  1-loop functions

abstract:
  We derive the Callan-Symanzik equation of the electroweak Standard Model in
the QED-like on-shell parameterization. The various coefficient functions, the
$\beta$-functions and anomalous dimensions, are determined in one-loop order in
the most general linear gauge compatible with rigid symmetry. In this way the
basic elements for a systematic investigation of higher-order leading
logarithmic contributions in the Standard Model are provided. The one-loop
$\beta$-function of the electromagnetic coupling turns out to be independent of
mass ratios and it is QED-like in this sense. Besides the QED-contributions of
fermions it contains non-abelian contributions from vectors and ghosts with
negative sign, which overcompensate the contributions of the fermions if one
restricts the latter to one fermion generation. We also compare our results
with the symmetric theory and give relations between the $\beta$-functions of
the spontaneously broken and the symmetric theory valid in one-loop order.


title: Special Symmetric Quark Mass Matrices

abstract:
  We give a procedure to construct a special class of symmetric quark mass
matrices near the democratic limit of equal Yukawa couplings for each sector.
It is shown that within appropriate weak-bases, the requirements of symmetry
and arg(det[M])=0 are very strong conditions, that necessarily lead to a
Cabibbo angle given by |V_us|=Sqrt[md/ms], and to |V_cb|~ms/mb, in first order.
In addition, we prove that the recently classified ansatze, which also
reproduce these mixing relations, and which were based on the hypothesis of the
Universal Strength for Yukawa couplings, where all Yukawa couplings have equal
moduli while the flavour dependence is only in their phases, are, in fact,
particular cases of the generalized symmetric quark mass matrix ansatze we
construct here. In an excellent numerical example, the experimental values on
all quark mixings and masses are accommodated, and the CP violation phase
parameter is shown to be crucially dependent on the values of mu and V_us.