title:
Nucleon Decay and Neutrino Properties in a Mass Model based on an SO(10)
  Grand Unified Theory

abstract:
  In this work a mass model based on a SO(10) GUT with a global U(1) family
symmetry is discussed which leads to an asymmetric Nearest Neighbour
Interaction structure for the fermionic mass matrices. As a result of the
analysis one gets three solutions of the model which include several large
left- and right-handed fermion mixings. Those mixings are not observable in the
SM where only the CKM quark mixing matrix can be measured, but they have
testable effects on the branching ratios of nucleon decays in theories beyond
the SM. One finds that decay channels with positrons in the final state are
suppressed while channels with antimuons and antineutrinos are enhanced
compared to models with small mixings. The total nucleon lifetimes obtained
should be observable by future experiments. The SO(10) model also predicts the
masses and mixings of the light neutrinos. They are in the right range to
explain the anomalies of solar and atmospheric neutrinos by means of
oscillations, preferring the small angle MSW solution for the solar neutrino
deficit.


title:
Analyticity, crossing and the absorptive parts of the one-loop
  contributions to the quark-quark-gluon gauge boson four-point function

abstract:
  Starting from the known one-loop result for the $e^{+}e^{-}$-annihilation
process $e^{+}e^{-}\stackrel{\gamma,Z} {\longrightarrow} q\bar{q}g$ with
massless quarks we employ analyticity and crossing to determine the absorptive
parts of the corresponding one-loop contributions in Deep Inelastic Scattering
(DIS) and in the Drell-Yan process (DY). Whereas the ${\cal O}(\alpha_s^2)$
absorptive parts generate a non-measurable phase factor in the
$e^{+}e^{-}$-annihilation channel one obtains measurable phase effects from the
one-loop contributions in the deep inelastic and in the Drell-Yan case. We
compare our results with the results of previous calculations where the
absorptive parts in DIS and in the DY process were calculated directly in the
respective channels. We also present some new results on the dispersive and
absorptive contributions of the triangle anomaly graph to the DIS process.


title: The Past and Future of S-Matrix Theory

abstract:
  Contents: 1. Introduction. 2. The Early Years. 2.1 Living Without Field
Theory. 2.2 Initial Postulates. 2.3 Further Postulates. 2.4 QCD and a Final
Postulate. 2.5 Analyticity in Field Theory. 3. Axiomatic S-Matrix Theory. 3.1
Unitarity, Bubble Diagrams and Landau Diagrams. 3.2 The Landau Equations and
the ``$+~ \alpha$'' Condition. 3.3 Macrocausality and Essential Support. 3.4
The Structure Theorem. 3.5 Local Discontinuity Formulae. 3.6 Good and Bad
Functions and the Steinmann Relations. 3.7 Global Discontinuity Formulae. 3.8
CPT, Hermitian Analyticity, etc. 3.9 Holonomy. 4. Asymptotic S-Matrix Theory.
4.1 The Elastic Scattering Asymptotic Dispersion Relation. 4.2 Multiparticle
Kinematics and Analyticity Domains. 4.3 Multiparticle Asymptotic Dispersion
Relations. 4.4 Classification of Multiple Discontinuities. 5. Multi-Regge
Theory. 5.1 Partial-Wave Expansions. 5.2 Froissart-Gribov Continuations.
Sommerfeld-Watson Representations. 5.4 Reggeon Unitarity. 6. Reggeon Field
Theory. 6.1 Pomeron Phase-Space and the Effective Lagrangian. 6.2 The Critical
Pomeron. 6.3 The Super-Critical Pomeron. 7. QCD and the Critical Pomeron. 7.1
Reggeon Diagrams in QCD. 7.2 Color Superconductivity and the Super-Critical
Pomeron. 7.3 Quark Saturation and an Infra-Red Fixed Point. 7.4 Uniqueness of
the S-Matrix ?


title: Limits on excited tau leptons masses from leptonic tau decays

abstract:
  We study the effects induced by excited leptons on the leptonic tau decay at
one loop level. Using a general effective lagrangian approach to describe the
couplings of the excited leptons, we compute their contributions to the
leptonic decays and use the current experimental values of the branching ratios
to put limits on the mass of excited states and the substructure scale.


title: Top Spin and Experimental Tests

abstract:
  We examine pair mass dependence near threshold as a means to measure the spin
of the top quark in hadron collisions, and we discuss the possibility that a
top squark signal could be hidden among the top events.


title: Virtual Color Superconductivity--Status and Perspective

abstract:
  The status of our understanding of the properties and manifestations of color
superconductivity at zero and low density is briefly reviewed. Future
possibility is highlighted.


title: Space-time structure of a bound nucleon

abstract:
  Distortions of bound nucleon space-time structure, measured in deep inelastic
scattering off nuclei, are discussed from view-point of a theoretical approach
based on the Bethe-Salpeter formalism. It is shown that modification of the
structure function $F_2^{\rm N}$ results from relative time dependence in Green
functions of bound nucleons. The modification plays fundamental role in
analysis of deep inelastic scattering experiments and allows one to obtain new
information about nucleon structure.


title:
Inclusive jet production on the nucleus in the perturbative QCD with
  $N_c\to\infty$

abstract:
  Using the recently found hA amplitude, single and double inclusive jet
production rates on the nucleus are studied in the perturbative QCD with
$N_c\to\infty$. Jet multiplicities are found to grow with $A$ and energy as
$A^{2/9}s^\Delta$ where $\Delta$ is the BFKL intercept. Long range correlations
are found to behave as $A^{4/9}s^{2\Delta}$ and change from negative to
positive at a certain high energy.


title: Nucleus-nucleus scattering in perturbative QCD with $N_c\to\infty$

abstract:
  In the perturbative QCD with $N_c\to\infty$ equations for the amplitude of
the nucleus-nucleus scattering are derived by the effective field method. The
asymptotic form of the solution is discussed. It is argued that in the
high-energy limit the total nucleus-nucleus cross-sections become constant and
purely geometrical.


title: Transverse QCD Dynamics Near the Light Cone

abstract:
  Starting from the QCD Hamiltonian in near-light cone coordinates, we study
the dynamics of the gluonic zero modes. Euclidean 2+1 dimensional lattice
simulations show that the gap at strong coupling vanishes at intermediate
coupling. This result opens the possibility to synchronize the continuum limit
with the approach to the light cone.


title: Confinement and short distance physics

abstract:
  We consider non-perturbative effects at short distances in theories with
confinement. The analysis is straightforward within the Abelian models in which
the confinement arises on classical level. In all cases considered (compact
U(1) in 3D and 4D, dual Abelian Higgs model) there are non-perturbative
contributions associated with short distances which are due to topological
defects. In QCD case, both classical and quantum effects determine the role of
the topological defects and the theoretical analysis has not been completed so
far. Generically, the topological defects would result in 1/Q^2 corrections
going beyond the standard Operator Product Expansion. We review existing data
on the power corrections and find that the data favor existence of the novel
corrections, at least at the mass scale of (1-2) GeV. We indicate crucial
experiments which could further clarify the situation on the phenomenological
side.


title: From Prototype SU(5) to Realistic SU(7) SUSY GUT

abstract:
  We construct a realistic SU(7) model which provides answers to many questions
presently facing the prototype SU(5) SUSY GUT. Among them are a solution to the
doublet-triplet splitting problem, string scale unification, proton decay, the
hierarchy of baryon vs lepton number violation and neutrino masses.


title: Resonance Production of Three Neutral Supersymmetric Higgs Bosons at LHC

abstract:
  Multiple production of Higgs particles is essential to study Higgs
self-couplings at future high-energy colliders. In this paper we calculated the
resonance contributions to the production of three lightest neutral
supersymmetric Higgs bosons in gluon fusion at LHC. The cross sections due to
trilinear Higgs couplings is sizeable but the measurement of the quartic
coupling hhhH(h) seems to be impossible.


title: Muon colliders and the non-perturbative dynamics of the Higgs boson

abstract:
  A muon collider operating in the TeV energy range can be an ideal s-channel
Higgs boson factory. This is especially true for a heavy Higgs boson. The
non-perturbative dynamical aspects of such a Higgs boson were recently
investigated with large N expansion methods at next to leading order, and
reveal the existence of a mass saturation effect. Even at strong coupling, the
Higgs resonance remains always below 1 TeV. However, if the coupling is strong
enough, the resonance becomes impossible to be detected.


title: Direct and indirect limits on the electro-magnetic form factors of WIMPs

abstract:
  We use the results of direct and indirect searches for weakly interacting
massive particles (WIMPs) to obtain bounds on various electro-magnetic form
factors of WIMPs. The limits on the recoil signal in underground dark matter
detection experiments, with standard assumptions about the density and r.m.s.
velocity of WIMPs in the halo, can be translated into the following
model-independent bounds on the magnetic dipole, electric dipole, quadrupole
and anapole moments and the polarizability of WIMPs: mu/mu_n < 1.4 10^{-4}, d <
5 10^{-21}e cm, Q < 6 10^{-7}fm^2, a/mu_n < 3 10^{-2} fm, and chi < 5
10^{-8}fm^3 for a WIMP mass of 100 GeV. The limits on fluxes of highly
energetic neutrinos produced in the annihilation of WIMPs in the center of the
earth and the sun lead to somewhat stronger, but more model dependent bounds.


title:
New constraints for non-Newtonian gravity in nanometer range from the
  improved precision measurement of the Casimir force

abstract:
  We obtain constraints on non-Newtonian gravity following from the improved
precision measurement of the Casimir force by means of atomic force microscope.
The hypothetical force is calculated in experimental configuration (a sphere
above a disk both covered by two metallic layers). The strengthenings of
constraints up to 4 times comparing the previous experiment and up to 560 times
comparing the Casimir force measurements between dielectrics are obtained in
the interaction range 5.9 nm$\leq\lambda\leq 115 $nm. Recent speculations about
the presence of some unexplained attractive force in the considered experiment
are shown to be unjustified.


title:
Resonant sneutrino production in Supersymmetry with R-parity violation
  at the LHC

abstract:
  The resonant production of sneutrinos at the LHC via the R-parity violating
couplings $\l '_{ijk} L_i Q_j D^c_k$ is studied through its three-leptons
signature. A detailed particle level study of signal and background is
performed using a fast simulation of the ATLAS detector. Through the full
reconstruction of the cascade decay, a model-independent and precise
measurement of the masses of the involved sparticles can be performed. Besides,
this signature can be detected for a broad class of supersymmetric models, and
for a wide range of values of several $\l '_{ijk}$ coupling constants. Within
the MSSM, the production of a 900 GeV sneutrino for
$\lambda^{\prime}_{211}>0.05$, and of a 350 GeV sneutrino for
$\lambda^{\prime}_{211}>0.01$ can be observed within the first three years of
LHC running.


title: The east-west effect for atmospheric neutrinos

abstract:
  The atmospheric neutrino fluxes observed by underground detectors are not
symmetric for rotations around the vertical axis. The flux is largest
(smallest) for the nu's traveling toward east (west). This asymmetry is the
result of the effects of the geomagnetic field on the primary cosmic rays and
on their showers. The size of the asymmetry is to a good approximation
independent from the existence of neutrino oscillations, and can in principle
be predicted without any ambiguity due to existence of unknown new physics. We
show that there is an interesting hint of discrepancy between the experimental
measurement of the east-west asymmetry by Super-Kamiokande and the existing
theoretical predictions. We argue that the discrepancy is a real effect caused
by the neglect, in the existing calculations, of the bending of the charged
secondary particles (in particular of the muons) in the cosmic ray showers. The
inclusion of this effect in the calculation gives results in quantitative
agreeement with the data. We comment on the implications of this result for the
study of neutrino oscillations.


title: The decay omega(782) -> 5 pi in chiral theory

abstract:
  The arguments are put forward that the many pion decays omega ->2 pi^+ 2 pi^-
pi^0 and pi^+ pi^- 3 pi^0 provide an ideal test site for testing the
predictions of chiral models of the vector meson decays into many pions. Using
the approach based on the Weinberg Lagrangian or, in a new language, the
Lagrangian of hidden local symmetry added with the term induced by the
anomalous Lagrangian of Wess and Zumino, the partial widths of these decays are
evaluated, and their excitation curves in e^+e^- annihilation are obtained. The
discussed are the perspectives of the experimental study of the decays omega ->
5 pi in e^+e^- annihilation and photoproduction.


title:
Radiative corrections of $O(\a)$ for pion beta decay in the light-front
  quark model

abstract:
  If the CKM matrix element $V_{ud}$, that can be derived from superallowed
nuclear decays, neutron decay and pion beta decay, is used for a precision test
of the unitarity of the CKM matrix, the combination of the present world data
seems to indicate a small violation of the unitarity condition for the first
row. While an accurate calculation of the radiative corrections of $O(\a)$ (RC)
is crucial in order to determine the value of $V_{ud}$ as precisely as
possible, the theoretical analysis has been limited in the past by the rather
crude estimate of the effect of the hadronic structure. Only the contribution
due to the axial current depends on the hadronic environment. We develop a
strategy to deal with the influence of the hadronic structure on the decay
properties of the simplest hadron, the pion, and calculate the contribution of
the axial vector current to the RC, using a light-front model for the pion. Its
$q\bar{q}$ bound state structure is well described by two parameters,
constituent quark mass and confinement scale, that have been fixed by a
comparison with the data. We take into consideration three different groups of
two-loop diagrams, and derive their light-front representations. We discuss the
associated zero-mode problem and show that the respective light-front
amplitudes are free of spurious contributions. There is only a small model
dependent uncertainty of the final result for the RC for pion beta decay.


title:
Collisional Energy Loss of Fast Charged Particles in Relativistic
  Plasmas

abstract:
  Following an argument by Kirzhnits we rederive an exact expression for the
energy loss of a fast charged particle in a relativistic plasma using the
quantum field theoretical language. We compare this result to perturbative
calculations of the collisional energy loss of an energetic electron or muon in
an electron-positron plasma and of an energetic parton in the quark-gluon
plasma.

categories: hep-ph astro-ph nucl-th physics.plasm-ph


title: Random Matrix Theory and Chiral Symmetry in QCD

abstract:
  Random matrix theory is a powerful way to describe universal correlations of
eigenvalues of complex systems. It also may serve as a schematic model for
disorder in quantum systems. In this review, we discuss both types of
applications of chiral random matrix theory to the QCD partition function. We
show that constraints imposed by chiral symmetry and its spontaneous breaking
determine the structure of low-energy effective partition functions for the
Dirac spectrum. We thus derive exact results for the low-lying eigenvalues of
the QCD Dirac operator. We argue that the statistical properties of these
eigenvalues are universal and can be described by a random matrix theory with
the global symmetries of the QCD partition function. The total number of such
eigenvalues increases with the square root of the Euclidean four-volume. The
spectral density for larger eigenvalues (but still well below a typical
hadronic mass scale) also follows from the same low-energy effective partition
function. The validity of the random matrix approach has been confirmed by many
lattice QCD simulations in a wide parameter range. Stimulated by the success of
the chiral random matrix theory in the description of universal properties of
the Dirac eigenvalues, the random matrix model is extended to nonzero
temperature and chemical potential. In this way we obtain qualitative results
for the QCD phase diagram and the spectrum of the QCD Dirac operator. We
discuss the nature of the quenched approximation and analyze quenched Dirac
spectra at nonzero baryon density in terms of an effective partition function.
Relations with other fields are also discussed.


title: On the Theory of Fermionic Preheating

abstract:
  In inflationary cosmology, the particles constituting the Universe are
created after inflation due to their interaction with moving inflaton field(s)
in the process of preheating. In the fermionic sector, the leading channel is
out-of equilibrium particle production in the non-perturbative regime of
parametric excitation, which respects Pauli blocking but differs significantly
from the perturbative expectation. We develop theory of fermionic preheating
coupling to the inflaton, without and with expansion of the universe, for light
and massive fermions, to calculate analytically the occupation number of
created fermions, focusing on their spectra and time evolution. In the case of
large resonant parameter $q$ we extend for rermions the method of successive
parabolic scattering, earlier developed for bosonic preheating. In an expanding
universe parametric excitation of fermions is stochastic. Created fermions very
quickly, within tens of inflaton oscillations, fill up a sphere of radius
$\simeq q^{1/4}$ in monetum space. We extend our formalism to the production of
superheavy fermions and to `instant' fermion creation.


title:
Chiral symmetry breaking, color superconductivity and quark matter phase
  diagram: a variational approach

abstract:
  We discuss in this note simultaneous existence of chiral symmetry breaking
and color superconductivity at finite temperature and density in a
Nambu-Jona-Lasinio type model. The methodology involves an explicit
construction of a variational ground state and minimisation of the
thermodynamic potential. There exists solutions to the gap equations at finite
densities with both quark antiquark as well as diquark condensates for the
"ground" state. However, such a phase is thermodynamically unstable with the
pressure being negative in this region. We also compute the equation of state,
and obtain the structure of the phase diagram in the model.


title:
Lattice calculation of $1/p^2$ corrections to $\alpha_s$ and of
  $\Lambda_{\rm {QCD}}$ in the $\widetilde{MOM}$ scheme

abstract:
  We report on very strong evidence of the occurrence of power terms in
$\as(p)$, the QCD running coupling constant in the $\widetilde{MOM}$ scheme, by
analyzing non-perturbative measurements from the lattice three-gluon vertex
between 2.0 and 10.0 GeV at zero flavor. While putting forward the caveat that
this definition of the coupling is a gauge dependent one, the general relevance
of such an occurrence is discussed. We fit $\Lambda_{\bar{\rm MS}}^{(n_f=0)}=
237 \pm 3 ^{+ 0}_{-10}$ MeV in perfect agreement with the result obtained by
the ALPHA group with a totally different method.
  The power correction to $\as(p)$ is fitted to $(0.63\pm 0.03 ^{+ 0.0}_{-
0.13}) {\rm GeV}^2/p^2$.


title: Transverse Dynamics of Hard Partons in Nuclear Media and the QCD Dipole

abstract:
  We derive the non-abelian generalization of the Furry approximation which
describes the transverse dynamical evolution of a hard projectile parton inside
a spatially extended colour target field. This provides a unified starting
point for the target rest frame description of the nuclear dependence of a
large class of observables. For the case of the virtual gamma -> q-qbar
photoabsorption cross section, we investigate then in detail under which
conditions the nuclear dependence encoded in the Furry wavefunctions can be
parametrized by a q-qbar QCD dipole cross section. The important condition is
colour triviality, i.e., the property that for arbitrary N-fold rescattering
contributions the only non-vanishing colour trace is N_c C_F^N. We give proofs
for the colour triviality of the inelastic, diffractive and total
photoabsorption cross section measured inclusively or with one jet resolved in
the final state. Also, we list examples for which colour interference effects
remain. Colour triviality allows us to write the gamma -> q qbar contribution
to the DIS nuclear structure function F_2 for small Bjorken x in terms of a
path integral which describes the transverse size evolution of the q-qbar pair
in the nuclear colour field. This expression reduces in an opacity expansion to
the N=1 result of Nikolaev and Zakharov, and in the eikonal approximation to
the Glauber-type rescattering formulas first derived by Mueller. In the
harmonic oscillator approximation of the path integral, we quantify deviations
from the eikonal limit. Their onset is characterized by the scales L/l_f and
E_t L which relate the longitudinal extension L of the nuclear target to the
coherence length l_f and the total transverse energy E_t accumulated by the
q-qbar pair.


title:
Decay widths of the neutral CP-even MSSM Higgs bosons in the
  Feynman-diagrammatic approach

abstract:
  In the Minimal Supersymmetric Standard Model (MSSM) we incorporate the
Higgs-boson propagator corrections, evaluated up to two-loop order, into the
prediction of $\Gamma$(h -> ff) and BR(h -> ff) for f = b, c, $\tau$. The
propagator corrections consist of the full one-loop contribution, including the
effects of non-vanishing external momentum, and corrections of O(alpha alpha_s)
at the two-loop level. The results are supplemented with the dominant one-loop
QED corrections and final state QCD corrections from both gluons and gluinos.
The effects of the two-loop propagator corrections and of the one-loop gluino
contributions are investigated in detail. Our results are compared with the
result obtained within the renormalization group approach. Agreement within 10%
is found for most parts of the MSSM parameter space.


title: On the $\eta$ and f$_1$(1420) Couplings to the Nucleon

abstract:
  We consider neutral pseudoscalar, $\eta $, and axial vector, $f_1(1420)$,
mesons in the OZI-rule-respecting flavor basis, $\lbrace (\bar s s), {1\over
\sqrt{2}}(\bar u u + \bar d d)\rbrace$, and suggest a scenario for their
coupling to the nucleon. Within this framework, the non--strange parts of the
$\eta N$ and f$_1 N$ couplings are modeled by means of triangular $a_0\pi N$,
and $K K^* (\Lambda /\Sigma)$ vertices, while the strange ones partly proceed
via Goldberger-Treiman relations, which have been concluded solely on the
grounds of current universality. The suggested model explains the observed
suppression of the $\eta N$ coupling with respect to the constituent quark
model expectations, and predicts the coupling of $f_1$ to the nucleon.


title: rho_T Production via W_L Z_L Fusion at Hadronic Colliders

abstract:
  Multiscale technicolor models predict the existence of high mass resonances
at hadron colliders. Although the quark fusion process of production dominates,
vector boson fusion offers the advantage of allowing forward jet tagging for
background suppression. We calculate here the cross section and differential
distributions for $\rho_T$ production in the vector boson fusion channel at the
LHC.


title: Phase transitions from preheating in gauge theories

abstract:
  We show by studying the Abelian Higgs model with numerical lattice
simulations that non-thermal phase transitions arising out of preheating after
inflation are possible in gauge-Higgs models under rather general
circumstances. This may lead to the formation of gauged topological defects
and, if the scale at which inflation ends is low enough, to electroweak
baryogenesis after preheating.


title: The use of neutrino beams from muon storage rings

abstract:
  I give a brief overview of the physics potential of short baseline
experiments at neutrino factories, i.e. facilities providing high energy and
high intensity neutrino beams, like the one planned to be built in connection
with the proposed high energy muon storage ring. These facilities would offer a
unique opportunity to perform new precision studies of QCD and electroweak
interactions. New types of measurements, such as studies of gluon density of
the nucleon via charmonium production and extractions of V_cb and V_ub CKM
matrix elements, will become possible. Interesting new physics scenarios can
also be explored.


title: Thermodynamics, strange quark matter, and strange stars

abstract:
  Because of the mass density-dependence, an extra term should be added to the
expression of pressure. However, it should not appear in that of energy
according to both the general ensemble theory and basic thermodynamic
principle. We give a detail derivation of the thermodynamics with
density-dependent particle masses. With our recently determined quark mass
scaling, we study strange quark matter in this new thermodynamic treatment,
which still indicates a possible absolute stability as previously found.
However, the density behavior of the sound velocity is opposite to the previous
finding, but consistent with one of our recent publication. We have also
studied the structure of strange stars using the obtained equation of state.


abstract:
  Order \alpha^2 corrections to the decay rate of orthopositronium are
calculated in the framework of nonrelativistic QED. The resulting contribution
is found to be in significant disagreement with one set of experimental
measurements though another experiment is in agreement with theory.


title: Status of Electroweak Phase Transition and Baryogenesis

abstract:
  I review recent progress on the electroweak phase transition and
baryogenesis, focusing on the minimal supersymmetric standard model as the
source of new physics.


title:
Renormalization Scheme and Higher Loop Stability in Hadronic $\tau$
  Decay within Analytic Perturbation Theory

abstract:
  We apply an analytic description to the inclusive decay of the $\tau$ lepton.
We argue that this method gives not only a self-consistent description of the
process both in the timelike region by using the initial expression for
$R_\tau$ and in the spacelike domain by using the analytic properties of the
hadronic correlator, but also leads to the fact that theoretical uncertainties
associated with unknown higher-loop contributions and renormalization scheme
dependence can be reduced dramatically.


title:
Timelike and spacelike QCD characteristics of the $e^+e^-$ annihilation
  process

abstract:
  We consider the Adler $D$-function, which is defined in the spacelike region,
and the $e^+e^-$ annihilation ratio smeared, according to the Poggio, Quinn,
and Weinberg method, which is determined for timelike argument. We show that
the method of the nonperturbative $a$-expansion allows one to describe these
Euclidean and Minkowskian characteristics of the process of $e^+e^-$
annihilation down to the lowest energy scales.


title: The QCD heavy-quark potential to order v^2: one loop matching conditions

abstract:
  The one-loop QCD heavy quark potential is computed to order v^2 in the color
singlet and octet channels. Several errors in the previous literature are
corrected. To be consistent with the velocity power counting, the full
dependence on |p' + p|/|p' - p| is kept. The matching conditions for the NRQCD
one-loop potential are computed by comparing the QCD calculation with that in
the effective theory. The graphs in the effective theory are also compared to
terms from the hard, soft, potential, and ultrasoft regimes in the threshold
expansion. The issue of off-shell versus on-shell matching and gauge dependence
is discussed in detail for the 1/(m k) term in the potential. Matching on-shell
gives a 1/(m k) potential that is gauge independent and does not vanish for
QED.


title: Top Quark Physics

abstract: We review the prospects for studies of the top quark at the LHC.


title: What are sterile neutrinos good for?

abstract:
  Taken at face value, current experimental data indicate the existence of a
new particle, the sterile neutrino, which must be a singlet under the Standard
Model gauge group. Although they are not detectable through traditional means,
such particles have interesting observable consequences for particle
astrophysics and cosmology. Here we examine these implications and discuss, in
particular, sterile neutrino dark matter and the relationship between
matter-enhanced active-sterile neutrino transformation and the synthesis of
heavy elements in supernovae.


title: Treatment of Heavy Quarks in Deeply Inelastic Scattering

abstract:
  We investigate a simplified version of the ACOT prescription for calculating
deeply inelastic scattering from Q^2 values near the squared mass M_H^2 of a
heavy quark to Q^2 much larger than M_H^2.


title: A Light Sterile Neutrino in the TopFlavor Model

abstract:
  A scenario based on the TopFlavor model is presented to explain the origin of
a light sterile neutrino as indicated by all combined neutrino oscillation
experiments. The model is phenomenologically well motivated and compatible with
all available low-energy data. The derived nuetrino mass matrix can
qualitatively explain the observed hierarchy in the neutrino mass splittings as
indicated by the neutrino oscillation data. Numerical results are obtained for
special cases.


title: Ultra High Energy Cosmic Rays from Axion Stars

abstract:
  We propose a model in which ultra high energy cosmic rays are produced by
collisions between neutron stars and axion stars. The acceleration of such a
cosmic ray is made by the electric field, $\sim 10^{15} (B/10^{12} {G}) {eV}
{cm}^{-1}$, which is induced in an axion star by the strong magnetic field
$B>10^{12}$ G of a neutron star. As we have shown previously, similar
collisions generate gamma ray bursts when the magnetic field is much smaller,
e.g. $\sim 10^{10}$ G. If we assume that the axion mass is $\sim 10^{-9}$ eV,
we can explain huge energies of the gamma ray bursts $\sim 10^{54}$ erg as well
as the ultra high energies of the cosmic rays $\sim 10^{20}$ eV. In addition,
it turns out that these axion stars are plausible candidates for MACHOs. We
point out a possibility of observing monochromatic radiations emitted from the
axion stars.


title: Analysis of atmospheric neutrino oscillations in three-flavor neutrinos

abstract:
  We analyze the atmospheric neutrino experiments of Super-Kamiokande (830-920
live days) using the three-flavor neutrino framework with the mass hierarchy
m_1 nearly equal m_2 << m_3. We study the sub-GeV, multi- GeV neutrinos and
upward through-going and stopping muons zenith angle distributions taking
account of the Earth matter effects thoroughly. We obtain the allowed regions
of mass and mixing parameters Delm^2_{23}, theta_{13} and theta_{23}.
Delm^2_{23} is restricted to 0.002-0.01eV^2 and theta_{13}<13degrees,
35degrees<theta_{23}<55degrees in 90% C.L. For theta_{12}, there is no
difference between the large angle solar neutrino solution and small one. From
chi^2 fit, the minimum chi^2=55(54DOF) is obtained at
Delm^2_{23}=4x10^(-3)eV^2, theta_{13}=10degrees and theta_{23} =45degrees.


title:
Generating functionals method of N.N.Bogolyubov and multiple production
  physics

abstract:
  The generating functionals (GF) method in Bogolyubov's formulation and its
application for particle physics is considered. Effectiveness of the method is
illustrated by two examples. So, GF method can be used as the technical trick
solving the infinite sequence of algebraic equations. We will consider the
example, where GF allows express the multiplicity distributions (topological
cross sections) through the particles correlation functions (inclusive cross
sections) to `predict' so called the Koba-Nielsen-Olesen scaling. We will use
the GF to define validity of the thermal description of the multiple production
phenomena also. It will be seen that this will lead to the `correlations
relaxation condition' of N.N.Bogolyubov. This will allow to offer the
experimentally measurable criteria of applicability of thermodynamical
description of multiple production processes. In results we will find the
closed form of perturbation theory applicable for kinetic phase of
nonequilibrium processes. It is shown a way as the approach may be adapted to
the definite external conditions.


title: Phase transitions signal in inelastic hadron collisions

abstract:
  The consequence of vacuum instability against particles creation is described
using lattice gas model. It is shown that the tail of multiplicity distribution
should decrees slower than any power of $\exp\{-n\}$, but faster than any power
of $1/n$ if the vacuum is unstable against particles creation.


title: Soft partons production in deep inelastic kinematics

abstract:
  It is argued considering multiple production in the deep inelastic scattering
kinematics that the very high multiplicity events are extremely sensitive to
the low-x partons density.


title:
An estimate of higher twist at small x and low Q^2 based upon a
  saturation model

abstract:
  We investigate the influence of higher twist corrections to deep inelastic
structure functions in the low-$Q^2$ and small-$x$ HERA region. We review the
general features of the lowest-order QCD diagrams which contribute to twist-4
at small-$x$, in particular the sign structure of longitudinal and transverse
structure functions which offers the possibility of strong cancellations in
$F_2$. For a numerical analysis we perform a twist analysis of the saturation
model which has been very successful both in describing the structure function
and the DIS diffractive cross section at HERA. As the main conclusion, twist 4
corrections are not small in $F_L$ or $F_T$ but in $F_2=F_L + F_T$ they almost
cancel. This indicates the limitation on the use of the DGLAP formalism at
small $x$ and $Q^2$. We point out that $F_L$ analysis needs a large twist-4
correction. We also indicate the region of validity of the twist expansion.


title: Higher Order Corrections in Perturbative Quantum Chromo Dynamics

abstract:
  We present some techniques which have been developed recently or in the
recent past to compute Feynman graphs beyond one-loop order. These techniques
are useful to compute the three-loop splitting functions in QCD and to obtain
the complete second order QED corrections to Bhabha scattering.


title: Axial Anomaly and Polarized Radiative Decays

abstract:
  We extend the approach of Dolgov and Zakharov to the axial anomaly to study
polarized radiative decays. We analyse the pattern of mass singularity
cancellation in the corresponding decay rates. We compare polarized and
unpolarized cases. The cancellation of the infrared and collinear singularities
is verified to all powers of the lepton mass for the $\pi^+$ and $Z^0$
polarized radiative decays.


title: Preheating of massive fermions after inflation: analytical results

abstract:
  Non-perturbative production of fermions after chaotic inflation has been the
object of several studies in the very recent past. However, the results in the
most interesting case of production of massive fermions in an expanding
Universe were so far known only numerically. We provide very simple and
readable analytical formulae, both for the spectra of the created fermions and
for their total energy density. Their derivation is closely related to the one
adopted for bosons and exploits the fact that the production occurs during very
short intervals of nonadiabatical change of the fermionic frequency. Our
formulae show the presence of resonance bands if the expansion of the Universe
is neglected, and their disappearance when the latter is included. As in the
bosonic case, this last effect is due to the stochastic character that the
expansion gives to the whole process. Backreaction is considered in the last
part of the work. All our analytical results are in excellent agreement with
the previous numerical ones in the regime of validity of the latter. However, a
more accurate scaling for the energy density of the produced fermions is here
found.


title: Physics at e+e- Linear Colliders

abstract:
  I discuss the motivation and physics potential of an electron-positron linear
collider with a center-of-mass energy at the 1 TeV scale, in light of what we
may expect to learn with the LHC. The comparison is illustrated with examples
drawn from Higgs physics, top quark physics, and the search for large extra
spacetime dimensions.


title: Phi-measure of pions in high energy heavy-ion collisions

abstract:
  Event-by-Event fluctuations for high energy heavy-ion collisions are
investigated. The $\Phi$-measures are calculated for pions. It is found that
multiparticle symmetrization correlation has great influence on the value of
$\Phi$ if the phase space density is high. Previous derivation of
$\Phi$-measure has neglected multiparticle quantum correlation. So the
explanation of $\Phi$-measure as a measure of dynamical correlation is
reasonable only when multiparticles quantum correlation effects are smaller. We
argue that the $\Phi$-measure might be applicable at the SPS energy where the
pion phase space density is much less than one.


title: Scalar Exchange Forces and Generalized Most Attractive Channel Rule

abstract:
  We discuss the possibility that fermionic condensates arise from the
dominance of scalar exchange forces over vector gluon exchange. When a scalar
in the adjoint representation is exchanged in the reaction $A+A \to A+A$, the
usual most attractive channel (MAC) rule is reversed in sign, with the
consequence that the formation of a condensate with the largest possible
Casimir is favored. More generally, when a scalar in a general representation
is exchanged in the reaction $A+B \to B+A$, the group theoretic sum giving the
force sign and strength can be expressed in terms of a Racah coefficient for
the group in question. We illustrate the formalism in the case of the group
SU(2), and give possible applications to SO(10) and $E_6$ grand unification.


title: Polarized Moller Scattering Asymmetries

abstract:
  The utility of polarized electron beams for precision electroweak studies is
described. Parity violating Moller scattering asymmetries in e-e- --> e-e- are
discussed. Effects of electroweak radiative corrections and the running
sin^2(theta_W(Q^2)) are reviewed. The sensitivity of E158 (a fixed target e-e-
experiment at SLAC) and future e-e- collider studies to ``new physics'' is
briefly outlined.


title: Vacuum structure of a modified MIT Bag

abstract:
  An alternative to introducing and subsequently renormalizing classical
parameters in the expression for the vacuum energy of the MIT bag for quarks is
proposed in the massless case by appealing to the QCD trace anomaly and scale
separation due to asymptotic freedom. The explicit inclusion of gluons implies
an unrealistically low separation scale.


title: Unifying the Strengths of Forces in Higher Dimensions

abstract:
  We consider the embedding of the Standard Model fields in a
$(4+d)$-dimensional theory while gravitons may propagate in $d'$ extra, compact
dimensions. We study the modification of strengths of the gravitational and
gauge interactions and, for various values of $d$ and $d'$, we determine the
energy scale at which these strengths are unified. Special cases where the
unification of strengths is characterized by the absence of any hierarchy
problem are also presented.


title: Large N_c, chiral approach to M_eta' at finite temperature

abstract:
  We study the temperature dependence of the eta and eta' meson masses within
the framework of U(3)_L x U(3)_R chiral perturbation theory, up to
next-to-leading order in a simultaneous expansion in momenta, quark masses and
number of colours. We find that both masses decrease at low temperatures, but
only very slightly. We analyze higher order corrections and argue that large
N_c suggests a discontinuous drop of M_eta' at the critical temperature of
deconfinement T_c, consistent with a first order transition to a phase with
approximate U(1)_A symmetry.


title: The Effects of Non-Local Interactions in Rare B Decays, B -> X_s l^+l^-

abstract:
  The effects of non-local interactions in rare B decays, $\Bsll$, are
investigated. We show the correlation between the branching ratio and the
forward-backward asymmetry via two coefficients of the non-local interactions.
This will certainly help us find any deviations from the standard model through
the non-local interactions.


title:
Kaon Photoproduction of the Deuteron and the P-matrix Approach to the YN
  Final State Interaction

abstract:
  Strangeness photoproduction of the deuteron is investigated theoretically
making use of the covariant reaction formalism and the P-matrix approach the
final state hyperon-nucleon interaction. Remarkably simple analytical
expression for the amplitude is obtained. Pronounced effects due to final state
interaction are predicted.


title:
CP Violations in Lepton Number Violation Processes and Neutrino
  Oscillations

abstract:
  We examine the constraints on the MNS lepton mixing matrix from the present
and future experimental data of the neutrino oscillation and lepton number
violation processes. We introduce a graphical representation of the CP
violation phases which appear in the lepton number violation processes such as
neutrinoless double beta decay, the $\mu^--e^+$ conversion, and the K decay,
$K^-\to\pi^+\mu^-\mu^-.$ Using this graphical representation, we derive the
constraints on the CP violation phases in the lepton sector.


title: Bottom Production Asymmetries at the LHC

abstract:
  We present results on bottom hadron production asymmetries at the LHC within
both the Lund string fragmentation model and the intrinsic bottom model. The
main aspects of the models are summarized and specific predictions for pp
collisions at 14 TeV are given. Asymmetries are found to be very small at
central rapidities increasing to a few percent at forward rapidities. At very
large rapidities intrinsic production could dominate but this region is
probably out of reach of any experiment.


title: Electroweak Physics, Theoretical Aspects

abstract:
  I discuss two aspects of the electroweak interactions: the status of the
precision measurement of the electroweak parameters and their impact on the
Higgs search at future colliders.


title: A General Classification of Three-Neutrino Models and U_e3

abstract:
  A classification of models with three light neutrinos is given. This
classification includes virtually all of the three-neutrino models proposed in
the last few years, of which there are approximately one hundred. The essential
ideas, attractive features, and characteristic problems of the different
classes of model are discussed. The classification is based principally on how
the large \nu_{\mu} - \nu_{\tau} mixing is obtained. A general discussion of
the mixing parameter U_{e3} is then given, showing what values are to be
expected for it in each type of model.


title: Critical couplings for chiral symmetry breaking via instantons

abstract:
  Using an instanton effective action formalism, we compute the critical
coupling for the nonperturbative formation of a dynamical mass via instantons
in non-Abelian gauge theories with N_f massless fermions. Only continuous phase
transitions are considered. For large values of N_f the critical couplings are
found to be much smaller than the equivalent critical couplings obtained from
gauge exchange calculations in the ladder approximation.


title: Virtual Color Superconductivity and Nucleon Structure

abstract:
  The observed electromagnetic (EM) properties of a nucleon at high energy are
studied to search for a possible metastable color superconducting phase, called
a virtual phase, that has an energy density close to the true ground state of
the vacuum. The discussion is based on a mechanism of spontaneous partial
breaking of the EM U(1) gauge symmetry inside a color superconductor. Favorable
evidences for such a scenario are found.


title:
Charge-odd and single-spin effects in two-pion production in ep
  collisions

abstract:
  We consider double-photon and bremsstrahlung mechanisms for the production of
two charged pions in high-energy electron (or proton) scattering off a
transversely polarised proton. Interference between the relevant amplitudes
generates a charge-odd contribution to the cross-section for the process. In
the kinematical configuration with a jet nearly collinear to the electron, the
spin-independent part may be used to the determine phase differences for
pion-pion scattering in states with orbital momentum 0 or 2 and 1, while for
the configuration with a jet nearly collinear to the proton, the spin-dependent
part may be used to explain the experimental data for single-spin correlations
in the production of negatively charged pions. We also discuss the backgrounds
and estimate the accuracy of the results to be better than 10 %. In addition,
simplified formulae derived for specific kinematics, with small total
transverse pion momenta, are given. The accuracy is estimated to remain at the
same level despite the lower energy.


title: On Symmetry of Elementary Particles

abstract:
  The new quantum number \sigma is introduced. It is shown that the
conservation of \sigma-number results in the conservation of difference between
baryon and lepton numbers obtained earlier by Georgi and Glashow. The
conservation of \sigma -number also predicts that electron type neutrino mass
is exactly zero. The quark-lepton symmetry is discussed. It is shown that the
nature of quark-lepton symmetry is reflected by the fact that elementary
particles of the same generation are subject to the symmetry transformation
represented by 4-group of diedr. It is also shown that colorless elementary
particles are subject to the same symmetry transformation. The new elementary
particles (transbaryons) are predicted.


title:
Lepton flavor violation in the supersymmetric standard model with
  vectorlike leptons

abstract:
  Lepton flavor violating processes are obtained from the mixing between
ordinary leptons and vectorlike SU(2)_L doublet leptons which may originate in
E_6. The effects of this lepton mixing are, however, suppressed naturally by
the hierarchy of the charged lepton masses. In the supersymmetric model,
significant effects of lepton flavor violation may appear rather through
slepton mixing, which is in the present case generated by radiative corrections
with ordinary-exotic lepton couplings. We are especially interested in the mu
-> e gamma decay. In the model without the bare mass term of vectorlike
leptons, the supersymmetric contributions are rather suppressed due to the
approximate U(1)_e X U(1)_mu. It is, however, remarkable that they are
substantially enhanced by tan^6 beta. Then, B(mu -> e gamma) might be
comparable to the experimental bound for large tan beta. In the model with the
bare mass term, much larger contributions are obtained through slepton mixing.
These investigations show that the supersymmetric effects on lepton flavor
violation due to the vectorlike leptons can be observed in the near future
experiments.


title: Top quark rare decays in the standard model and beyond

abstract:
  Theoretical predictions for the top quark rare decays are reviewed within and
beyond the standard model. Expectations at the CERN Large Hadron Collider are
discussed.


title: Top quark, heavy fermions and the composite Higgs boson

abstract:
  We study the properties of heavy fermions in the vector-like representation
of the electro-weak gauge group $SU(2)_W\times U(1)_Y$ with Yukawa couplings to
the standard model Higgs boson. Applying the renormalization group analysis, we
discuss the effects of heavy fermions to the vacuum stability bound and the
triviality bound on the mass of the Higgs boson. We also discuss the
interesting possibility that the Higgs particle is composed of the top quark
and heavy fermions. The bound on the composite Higgs mass is estimated using
the method of Bardeen, Hill and Lindner, 150GeV$\leq m_H\leq$ 450GeV.


title: Seesaw model and its Lorentz group formulation

abstract:
  For two flavors, the seesaw matrix can be identified with a two dimensional
representation of the Lorentz group. This analogy facilitates the computation
of physical neutrino parameters, while giving an intuitive understanding of the
results. It is found that the induced mixing angle exhibits resonance behavior.
For maximal mixing, we derive a precise relation among the right-handed mixing
angle, the Majorana mass ratio, and their phase.


title: QED correction to radiative tail from elastic peak in DIS

abstract:
  We calculate DIS cross section under kinematical requirements when a final
hadron state is a single proton. The process in the lowest order is known as
radiative tail from elastic peak. We take into account correction, coming from
emission of virtual and soft real photons, to the amplitude of this process as
well as the one, induced by emission of additional hard photon and a hard pair.
Resulting contributions of these channels are presented in the leading and,
partly, next-to-leading logarithmic approximations. Some general expressions
for the photon contributions are given. Numerical results are presented for
kinematical conditions of the current experiments on DIS.


title: A new twist to preheating

abstract:
  Metric perturbations typically strengthen field resonances during preheating.
In contrast we present a model in which the super-Hubble field resonances are
completely {\em suppressed} when metric perturbations are included. The model
is the nonminimal Fakir-Unruh scenario which is exactly solvable in the
long-wavelength limit when metric perturbations are included, but exhibits
exponential growth of super-Hubble modes in their absence. This gravitationally
enhanced integrability is exceptional, both for its rarity and for the power
with which it illustrates the importance of including metric perturbations in
consistent studies of preheating. We conjecture a no-go result - there exists
no {\em single-field} model with growth of cosmologically-relevant metric
perturbations during preheating.


title:
Discrete Ambiguities in B-Decay CP Asymmetries and the Search for New
  Physics

abstract:
  The first measurements of CP violation in the B system will probably extract
$\sin 2\alpha$, $\sin 2\beta$ and $\cos 2\gamma$. Assuming that the CP angles
$\alpha$, $\beta$ and $\gamma$ are the interior angles of the unitarity
triangle, this determines the angle set $(\alpha,\beta,\gamma)$ up to a twofold
discrete ambiguity. The presence of this discrete ambiguity can make the
discovery of new physics difficult: if only one of the two solutions is
consistent with constraints from other measurements in the B and K systems, one
is not sure whether new physics is present or not. I present examples of this
situation, and discuss ways to resolve the discrete ambiguity.


title: Wong's equations and the small x effective action in QCD

abstract:
  We propose a new form for the small x effective action in QCD. This form of
the effective action is motivated by Wong's equations for classical, colored
particles in non-Abelian background fields. We show that the BFKL equation,
which sums leading logarithms in x, is efficiently reproduced with this form of
the action. We argue that this form of the action may be particularly useful in
computing next-to- leading-order results in QCD at small x.


title: Neutrino Proper Time?

abstract:
  An electron neutrino can have the quantum phase of an electron, i.e. share
its internal clock, if the neutrino takes a path in space-time that is not in
the direction of its energy-momentum. Each flavor neutrino would then have a
different internal clock; a muon neutrino would have a muon clock and a tau
neutrino would have a tau clock. Perhaps surprisingly, there is some evidence
suggesting neutrinos have such clocks. If muon neutrinos travel on space-like
paths then some atmospheric muon neutrinos would take such paths backwards into
outer space and not be observed. These are lost at the source and have nothing
to do with oscillations or flavor-changing in flight. The expected depletion of
source muon neutrinos is shown here to be 9%, which accounts for half of the
missing muon neutrino source flux reported by Super-Kamiokande. Since there is
no depletion in the electron neutrino flux source reported at SK and SN1987A
electron neutrinos seem to have traveled at the speed of light, the electron
neutrino travels on a light-like path. Accelerator-based experiments could be
arranged to confirm the reverse motion of muon neutrinos.


title:
Mirror matter and heavy singlet neutrino oscillations in the early
  universe

abstract:
  We investigate the mixing of heavy gauge singlet neutrinos in a mirror matter
model employing the seesaw mechanism. The parameter constraints that must be
satisfied to prevent the overproduction of mirror matter in the early universe
are deduced. We find that no fine tuning in the heavy neutral fermion sector is
required for this mirror matter model to satisfy cosmological constraints.
Baryogenesis scenarios are briefly discussed in the context of the mirror
model.


title:
Charm multiplicity and the branching ratios of inclusive charmless b
  quark decays in the general two-Higgs-doublet models

abstract:
  In the framework of general two-Higgs-doublet models, we calculate the
branching ratios of various inclusive charmless b decays by using the low
energy effective Hamiltonian including next-to-leading order QCD corrections,
and examine the current status and the new physics effects on the determination
of the charm multiplicity $n_c$ and semileptonic branching ratio $B_{SL}$.
Within the considered parameter space, the enhancement to the ratio $BR(b \to s
g)$ due to the charged-Higgs penguins can be as large as a factor of 8 (3) in
the model III (II), while the ratio $BR(b \to no charm)$ can be increased from
the standard model prediction of 2.49% to 4.91% (2.99%) in the model III (II).
Consequently, the value of $B_{SL}$ and $n_c$ can be decreased simultaneously
in the model III. The central value of $B_{SL}$ will be lowered slightly by
about 0.003, but the ratio $n_c$ can be reduced significantly from the
theoretical prediction of $n_c= 1.28 \pm 0.05$ in the SM to $n_c= 1.23 \pm
0.05$, $1.18 \pm 0.05$ for $m_{H^+}=200, 100$ GeV, respectively. We find that
the predicted $n_c$ and the measured $n_c$ now agree within roughly one
standard deviation after taking into account the effects of gluonic charged
Higgs penguins in the model III with a relatively light charged Higgs boson.


title: Multiplicity distribution tails at high eneries energies

abstract:
  The idea that the hard channels may dominate in the very high multiplicity
processes is investigated. Quantitative realization of the `hard Pomeron', deep
inelastic scattering and large-angle annihilation mechanism combinations are
considered in the pQCD frame for this purpose.


title: Is the Polarized Antiquark Sea in the Nucleon Flavor Symmetric?

abstract:
  We show that the model which naturally explains the $\bar u \ne \bar d$
asymmetry in the nucleon and is in quantitative agreement with the Gottfried
sum rule data, also predicts that in the proton $\Delta \bar u > 0 > \Delta
\bar s > \Delta \bar d$ and $\Delta \bar u - \Delta \bar d > \bar d - \bar u >
0$. At the input scale, these results can be derived even analytically. Thus
the violation of the flavor symmetry is more serious in the polarized case than
in the unpolarized case. In contrast, many recent analyses of the polarized
data have made a simplifying assumption that all the three $\Delta \bar q$'s
have the same sign and magnitude. We point out the need to redo these analyses,
allowing for the alternate scenario as described above. We present predictions
of the model for the $W^-$ asymmetry in polarized $pp$ scattering, which can be
tested at RHIC; these are quite different from those available in the
literature.


title: Spin content of the $\Lambda$ hyperon

abstract:
  Using the known experimental data for the hyperon semileptonic decay
constants, we calculate integrated quark densities $\Delta q_\Lambda$ and $%
\Delta \Sigma_\Lambda$ for the hyperon $\Lambda$ with flavor SU(3) symmetry
breaking taken into account. Symmetry breaking is implemented with the help of
the chiral quark-soliton model in an approach, in which the dynamical
parameters are fixed by the experimental data for six hyperon semileptonic
decay constants. This parametrization allows us to reproduce the first moment
of the $g_1^{{\rm p}}(x)$ of the proton. For the $\Lambda$ we obtain: $\Delta
u_{\Lambda}=\Delta d_{\Lambda} \approx 0$ and $\Delta s_{\Lambda}$ of the order
of 1. Unfortunately large experimental errors of $\Xi^-$ decays propagate in
our analysis especially in the case of $\Delta\Sigma_{\Lambda}$ and $\Delta
s_{\Lambda}$. Only if the errors for these decays are reduced, the accurate
theoretical predictions for $\Delta\Sigma_{\Lambda}$ and $% \Delta s_{\Lambda}$
will be possible.


title:
Superheavy Majorana neutrino effects in the lepton-number violating e- +
  e- -> mu- + mu- process

abstract:
  In the minimal extension of the standard electroweak theory with ultra
massive Majorana neutrinos, the process e- + e- -> mu- + mu- could be
observable, in sharp contrast with the reaction e- + e- -> W- + W- which is
entirely controlled by neutrinoless double beta decay $\beta \beta_{0 \nu}$
data. Our result provides the process background that must be confronted "new
physics" models which postulate doubly charged particles, such as the gauge
bilepton Y^{-} in the $SU(3)_{\rm c} \times SU(3)_{\rm L} \times U(1)$ model,
the left-right $SU(2)_{\rm L} \times SU(2)_{\rm R} \times U(1)_{\rm B-L}$ one,
and its supersymmetric version with doubly charged Higgs multiplets.


title: Dual-Resonance Model and Multiple Production

abstract:
  The very high multiplicity (VHM) processes are considered to investigate
consequences of the dual resonance models reach (exponential) mass spectrum.
The virial decomposition is developed for description of the produced particles
short-rang (resonance) correlations. It is shown that the reach mass spectrum
is able to do more flat the VHM distribution: $\s_n=O(e^{-n})$ up to
multiplicities $n\simeq\bar{n}^2$, $\bar{n}$ is the mean multiplicity. But for
$n>>\bar{n}^2$ one should expect $\s_n<O(e^{-n})$.


title: Photoproduction constraints on J/psi-nucleon interactions

abstract:
  Using J/psi and open charm photoproduction data, we apply the vector meson
dominance model to obtain constraints on the energy dependence of the inelastic
J/psi-nucleon cross section. Predictions of short distance QCD are in accord
with these constraints, while recently proposed hadronic models for J/psi
dissociation strongly violate them.


title: Determining the quantum numbers of excited heavy mesons

abstract:
  We discuss the decays X^* -> Xe^+e^- (``Dalitz decays'') of excited heavy
mesons into their ground states and an electron-positron pair. We argue that
the measurement of the invariant mass spectrum of the lepton pair gives clear
indication on the quantum numbers of the excited meson and thus provides an
experimental test of the quark model predictions.


title: Fayet-Iliopoulos D-terms and anomaly mediated supersymmetry breaking

abstract:
  We show that in a minimal extension of the MSSM by means of an extra U(1)
gauge group, the negative mass-squared problem characteristic of the Anomaly
Mediated Supersymmetry Breaking scenario is naturally solved by means of
Fayet-Iliopoulos D-terms. We derive a set of sum rules for the sparticle masses
which are consequences of the resulting framework.


title:
Photon Plus Jet Cross Sections in Deep Inelastic ep Collisions at Order
  O(alpha^2 alpha_s)

abstract:
  The production of a hard and isolated photon accompanied by one or two jets
in large-Q2 deep inelastic ep scattering is calculated at next-to-leading
order. We include consistently contributions from quark-to-photon fragmentation
and study various differential cross sections and their dependence on isolation
cut parameters. Numerical results relevant for HERA experiments are presented.


title: Does Efficiency of High Energy Collisions Depend on a Hard Scale?

abstract:
  The multiplicity of charged hadrons in the current fragmentation region of
both the c.m.s. and the Breit frame of deep inelastic scattering is calculated
and compared with the HERA data. The results are in agreeement with Yang's
hypothesis that the efficiency of high energy processes increases at larger
momentum transfer.


title:
Predictive Grand Unified Textures for Quark and Neutrino Masses and
  Mixings

abstract:
  We propose new textures for the fermion Yukawa matrices which are
generalizations of the so-called Stech ansatz. We discuss how these textures
can be realized in supersymmetric grand unified models with horizontal symmetry
SU(3)_H among the fermion generations. In this framework the mass and mixing
hierarchy of fermions (including neutrinos) can emerge in a natural way. We
emphasize the central role played by the SU(3)_H adjoint Higgs field which
reduces SU(3)_H to U(2)_H at the GUT scale. A complete SO(10)\times SU(3)_H
model is presented in which the desired Yukawa textures can be obtained by
symmetry reasons. The phenomenological implications of these textures are
thoroughly investigated. Among various realistic possibilities for the Clebsch
factors between the quark and lepton entries, we find three different solutions
which provide excellent fits of the quark masses and CKM mixing angles.
Interestingly, all these solutions predict the correct amount of CP violation
via the CKM mechanism, and, in addition, lead to an appealing pattern of the
neutrino masses and mixing angles. In particular, they all predict nearly
maximal 23 mixing and small 12 mixing in the lepton sector, respectively in the
range needed for the explanation of the atmospheric and solar neutrino anomaly.


title:
Left-right asymmetries and exotic vector-boson discovery in
  lepton-lepton colliders

abstract:
  By considering left-right (L-R) asymmetries we study the capabilities of
lepton colliders in searching for new exotic vector bosons. Specifically we
study the effect of a doubly charged bilepton boson and an extra neutral vector
boson appearing in a 3-3-1 model on the L-R asymmetries for the processes
$e^-e^-\to e^-e^-$, $\mu^-\mu^-\to\mu^-\mu^-$ and $e^-\mu^-\to e^-\mu^-$ and
show that these asymmetries are very sensitive to these new contributions and
that they are in fact powerful tools for discovery this sort of vector bosons.


title: EDM-free supersymmetric CP violation with non-universal soft terms

abstract:
  Non-universality in the soft breaking terms is a common feature in most
superstring inspired SUSY models. This property is required to obtain sizeable
CP violation effects from SUSY and, on the other hand, can be used to avoid the
Electric Dipole Moment constraints. We take advantage of these qualities and
explore a class of SUSY models based on type I string theory where scalar
masses, gaugino masses and trilinear couplings are non-universal. In this
framework, we show that, in the presence of large SUSY phases, the bounds on
the Electric Dipole Moments can be controled without fine-tuning. At the same
time, we find that these phases, free from EDM constraints, lead to large
contributions to the observed CP phenomena in Kaon system and, in particular,
to direct CP violation in epsilon'/epsilon.


title: One Interesting New Sum Rule Extending Bjorken's to order {1/m_Q}

abstract:
  We explicitly check quark-hadron duality to order $(m_b-m_c)\Lambda/m_b^2$
for $b \to c l\nu$ decays in the limit $m_b-m_c \ll m_b$ including ground state
and orbitally excited hadrons. Duality occurs thanks to a new sum rule which
expresses the subleading HQET form factor $\xi_3$ or, in other notations,
  $a_+^{(1)}$ in terms of the infinite mass limit form factors and some level
splittings. We also demonstrate the sum rule, which is not restricted to the
condition $m_b-m_c \ll m_b$, applying OPE to the longitudinal axial component
of the hadronic tensor without neglecting the $1/m_b$ subleading contributions
to the form factors. We argue that this method should produce a new class of
sum rules, depending on the current, beyond Bjorken, Voloshin and the known
tower of higher moments. Applying OPE to the vector currents we find another
derivation of the Voloshin sum rule. From independent results on $\xi_3$ we
derive a sum rule which involves only the $\tau_{1/2}^{(n)}$ and
$\tau_{3/2}^{(n)}$ form factors and the corresponding level splittings. The
latter strongly supports a theoretical evidence that the $B$ semileptonic decay
into narrow orbitally-excited resonances dominates over the decay into the
broad ones, in apparent contradiction with some recent experiments. We discuss
this issue.


title: Gluon distributions in nucleons and pions at a low resolution scale

abstract:
  In this paper we study the gluon distribution functions in nucleons and pions
at a low resolution $Q^2$ scale. This is an important issue since parton
densities at low $Q^2$ have always been taken as an external input which is
adjusted through DGLAP evolution to fit the experimental data at higher scales.
Here, in the framework of a model recently developed, it is shown that the
hypothetical cloud of {\it neutral} pions surrounding nucleons and pions
appears to be responsible for the characteristic valence-like gluon
distributions needed at the inital low scale. As an additional result, we get
the remarkable prediction that neutral and charged pions have different
intrinsic sea flavor contents.


title:
Inflation in Models with Large Extra Dimensions Driven by a Bulk Scalar
  Field

abstract:
  We discuss inflation in models with large extra dimensions, driven by a bulk
scalar field. The brane inflaton is then a single effective field, obtained
from the bulk scalar field by scaling. The self interaction terms of the
effective brane inflaton are then naturally suppressed. The picture is
consistent with a fundamental string scale in the TeV range without the problem
of a superlight inflaton. If hybrid inflation is considered, the right
prediction for the density perturbations as observed by COBE can be obtained
without any fine tunning. The bulk inflaton then decays preferentially into
brane Higgses and reheating follows.


title: Constraining CP Violating Phases of the MSSM

abstract:
  Possible CP violation in supersymmetric (SUSY) extensions of the Standard
Model (SM) is discussed. The consequences of CP violating phases in the gaugino
masses, trilinear soft supersymmetry-breaking terms and the `mu' parameter are
explored. Utilizing the constraints on these parameters from electron and
neutron electric dipole moments, possible CP violating effects in B-physics are
shown. A set of measurements from the B-system which would overconstrain the
above CP violating phases is illustrated.


title:
How Valuable is Polarization at a Muon Collider? A Test Case:
  Determining the CP Nature of a Higgs Boson

abstract:
  We study the use of polarization asymmetries at a muon collider to determine
the CP-even and CP-odd couplings of a Higgs boson to $\mu^+mu^-$. We determine
achievable accuracy as a function of beam polarization and luminosity. The
appropriate techniques for dealing with the polarization precession are
outlined. Strategies especially appropriate for a two-Higgs-doublet model
(including the MSSM) are given. Our general conclusion is that polarization
will be very useful, especially if the proton source is such that full
luminosity in the storage ring can be retained even after imposing cuts on the
originally accepted muons necessary for $P\gsim 0.4$ for each beam.


title: Hadronic matrix elements from the lattice

abstract:
  Lattice matrix elements are briefly reviewed. In the quenched approximation
$f_B$, $B_B$ and $B_K$ are now under good control. Experimental hints for
$f^{\rm expt}_{D_S}> f^{\rm QQCD}_{D_S}$ are noted; precise determination of
$f_{D_S}$ from experiment as well as from the lattice is strongly advocated.
Lattice calculations of the form factor for $B\to\pi\ell\nu$ at relatively
large value of $q^2$ have made good progress and should be useful in
conjunction with precise measurement of the differential spectra expected from
$B$-factories. Recent attempt at $K\to \pi\pi$ using staggered quarks is
briefly discussed; use of non-perturbative renormalization, improved actions
and operators with staggered quarks is emphasized. Due to the good chiral
behavior of domain wall quarks it would be useful to study $K\to \pi\pi$ with
this discretization.


title: Multiplicity distribution tails at high energies

abstract:
  The idea that the hard channels may dominate in the very high multiplicity
processes is investigated. Quantitative realization of the `hard Pomeron', deep
inelastic scattering and large-angle annihilation mechanism combinations are
considered in the pQCD frame for this purpose.


title: Many pion decays of rho(770) and omega(782) mesons in chiral theory

abstract:
  The decays rho(770) to 4 pi and omega(782) to 5pi are considered in detail in
the approach based on the Weinberg Lagrangian obtained upon the nonlinear
realization of chiral symmetry, added with the term induced by the anomalous
Lagrangian of Wess and Zumino. The partial widths and excitation curves of the
decays rho^0 to 2 pi^+ 2 pi^-, pi^+ pi^- 2 pi^0, rho^{+-} to 2 pi^{+-} pi^{-+}
pi^0, rho^(+-} to pi^(+-} 3 pi^0 are evaluated for e^+e^- annihilation,
photoproduction and tau lepton decays. The results of calculations are compared
with the recent CMD-2 data on the decay rho^0 to 2 pi^+ 2 pi^- observed in
e^+e^- annihilation. The omega to 5 pi decay widths and excitation curves in
e^+e^- annihilation are obtained. The angular distributions for various
combinations of the final pions in the decays rho to 4 pi and omega to 5 pi are
written. The perspectives of the experimental study of the above decays in
e^+e^- annihilation, tau lepton decays and photoproduction are discussed.


title: The Evolution of the MLLA Parton Spectra

abstract:
  The evolution with energy scale of the partonic logarithmic scaled energy
spectra is investigated in the framework of the modified leading logarithmic
approximation (MLLA). The behaviour of the higher order moments is compared to
a number of analytic predictions and $\rm e^+e^-$ data.


title:
Implications of light-quark admixtures on charmonium decays into meson
  pairs

abstract:
  We argue that charmonium decays into meson pairs fall into two distinct
classes: one that is under control of perturbative QCD and another one that is
governed by a soft mechanism. We concentrate on a systematic analysis of J/Psi
(Psi') decays into a light pseudoscalar and a light vector meson and eta(c)
decays into a pair of light vector mesons. These processes belong to the second
class and are characterized by non-conserved hadronic helicity. It is assumed
that, in these cases, the charmonium state decays dominantly through a
light-quark Fock component by a soft mechanism which is characteristic of
OZI-rule allowed strong decays. Estimating the light-quark admixture by meson
mixing, we obtain a reasonable description of the branching ratios for these
processes.


title: The b-u skewed parton distributions

abstract:
  The b - u skewed parton distributions (SPDs) are discussed. The SPDs allow an
unambigous superposition of overlap and resonsance contributions and their
zeroth order moments represent the B - pi transition form factors. The values
of the form factors at maximum recoil are found to be F+(0)=F0(0)=0.22 with an
error of 0.05 in agreement with measurements of the B - pi pi branching ratio.
The branching ratios for the semi-leptonic B - pi decays are evaluated too.


title: The Asymptotic Regime of High Density QCD

abstract:
  We discuss the distinct approaches for high density QCD (hdQCD) in the
asymptotic regime of large values of parton density. We derive the AGL equation
for running coupling constant and obtain the asymptotic solution, demonstrating
that the property of partial saturation of the solution of the AGL equation is
not modified by the running of the coupling constant. We show that in this
kinematical regime, the solution of the AGL equation coincides with the
solution of an evolution equation, obtained recently using the
McLerran-Venugopalan approach. Using the asymptotic behavior of the gluon
distribution we calculate the $F_2$ structure function assuming first that the
leading twist relation between these two quantities is valid and second that
this relation is modified by the higher twist terms associated to the unitarity
corrections. In the first case we obtain that the corresponding $F_2$ structure
function is linearly proportional to $ln s$, which agrees with the results
obtained recently by Kovchegov using a distinct approach. In the second case a
softer behavior is obtained. In both cases, the $F_2$ structure function
unitarizes and the Froissart boundary is not violated in the asymptotic regime
of high density QCD. We conclude that the partial saturation of the gluon
distribution and the unitarization of the structure function are general
results, well-established by three distinct approaches for high dense systems.


title:
Neutrino scattering on polarized electron target as a test of neutrino
  magnetic moment

abstract:
  We suggest to use a polarized electron target for improving the sensitivity
of the search for the neutrino magnetic moment to the level $\sim
3\cdot10^{-13}\mu_B$ in the processes of neutrino (antineutrino) -- electron
scattering. It is shown that in this case the weak interaction term in the
total cross section is significantly suppressed comparing with unpolarized
case, but the electromagnetic term does not depend on electron polarization.


title: Analytic Continuation of Mellin Transforms up to two-loop Order

abstract:
  The analytic continuation of the Mellin transforms to complex values of N for
the basic functions $g_i(x)$ of the momentum fraction x emerging in the
quantities of massless QED and QCD up to two-loop order, as the unpolarized and
polarized splitting functions, coefficient functions, and hard scattering cross
sections for space- and time-like momentum transfer are evaluated. These Mellin
transforms provide the analytic continuations of all finite harmonic sums up to
the level of the threefold sums of transcendentality four, where the basis-set
${g_i(x)}$ consists of products of {\sc Nielsen}-integrals up to
transcendentality four. The computer code {\tt ANCONT} is provided.


title: Neutrino Oscillations: Some theoretical ideas

abstract:
  Talk given at Orbis Scientiae Conference, Coral Gables, FLA, Dec. 16-19,
1999. Talk surveys some recent three-neutrino models of neutrino masses and
mixings.


title: Remarks on anomalous U(1) symmetries in string theory

abstract:
  Anomalous U(1) gauge symmetries appear frequently both in heterotic and type
I/type II string theory. In the heterotic case we find at most a single
anomalous U(1), while in open string theories several such symmetries can
appear. We review the properties of the anomalous gauge bosons, the appearance
of Fayet-Iliopoulos terms and the concept of heterotic-type I duality.
Phenomenological applications of these symmetries might be different in the
type I/type II case compared to the heterotic one.


title: Non-Minimal and Non-Universal Supersymmetry

abstract:
  I motivate and discuss non-minimal and non-universal models of supersymmetry
and supergravity consistent with string unification at $10^{16}$ GeV.


title:
CP violating phase and quark mixing angles from flavour permutational
  symmetry breaking

abstract:
  The phase equivalence of the theoretical quark mixing matrix ${\bf V}^{th}$
derived from the breaking of the flavour permutational symmetry and the
phenomenological parametrizations ${\bf V}^{PDG}$ and ${\bf V}^{KM}$ is
explicitly exhibited. From here, we derive exact explicit expressions for the
three mixing angles and the CP violating phase of the two phenomenological
parametrizations in terms of the quark mass ratios $(m_{u}/m_{t}, m_{c}/m_{t},
m_{d}/m_{b}, m_{s}/m_{b})$ and the parameters $Z^{*1/2}$ and $\Phi^*$
characterizing the preferred symmetry breaking pattern. The computed values for
the CP violating phase and the mixing angles of the standard parametrization
advocated by the Particle Data Group are $\delta^*_{13}=73.2^\circ$,
$\sin\theta^*_{12}=0.222$,
  $\sin\theta^*_{13}=0.0036$, and $\sin\theta^*_{23}=0.040$. The computed
values of the CP-violating phase and the mixing angles of the Kobayashi-Maskawa
parametrization are $\delta^*_{KM}=96.4^\circ$, $\sin\theta^*_{1}=0.2225$,
$\sin\theta^*_{2}=0.0384$, and $\sin\theta^*_{3}=0.0162$. In both cases, the
numerical values of the mixing angles and CP-violating phase computed from
quark masses and the flavour symmetry breaking parameters coincide almost
exactly with the central values of the same parameters obtained from a fit to
experimental data.


title: Exact and approximate dynamics of the quantum mechanical O(N) model

abstract:
  We study a quantum dynamical system of N, O(N) symmetric, nonlinear
oscillators as a toy model to investigate the systematics of a 1/N expansion.
The closed time path (CTP) formalism melded with an expansion in 1/N is used to
derive time evolution equations valid to order 1/N (next-to-leading order). The
effective potential is also obtained to this order and its properties
areelucidated. In order to compare theoretical predictions against numerical
solutions of the time-dependent Schrodinger equation, we consider two initial
conditions consistent with O(N) symmetry, one of them a quantum roll, the other
a wave packet initially to one side of the potential minimum, whose center has
all coordinates equal. For the case of the quantum roll we map out the domain
of validity of the large-N expansion. We discuss unitarity violation in the 1/N
expansion; a well-known problem faced by moment truncation techniques. The 1/N
results, both static and dynamic, are also compared to those given by the
Hartree variational ansatz at given values of N. We conclude that late-time
behavior, where nonlinear effects are significant, is not well-described by
either approximation.


title: Two problems in thermal field theory

abstract:
  In this talk, I review recent progress made in two areas of thermal field
theory. In particular, I discuss various approaches for the calculation of the
quark gluon plasma thermodynamical properties, and the problem of its photon
production rate.


title: Running of the heavy quark production current and 1/k potential in QCD

abstract:
  The 1/k contribution to the heavy quark potential is first generated at one
loop order in QCD. We compute the two loop anomalous dimension for this
potential, and find that the renormalization group running is significant. The
next-to-leading-log coefficient for the heavy quark production current near
threshold is determined. The velocity renormalization group result includes the
alpha_s^3 ln^2(alpha_s) ``non-renormalization group logarithms'' of Kniehl and
Penin.


title: Is the polarized light flavor sea-quark asymmetric?

abstract:
  Simple formulas on $\Delta\bar d(x)-\Delta\bar u(x)$ are proposed for
extracting their values from polarized deep-inelastic semi-inclusive data. The
present SMC and HERMES data suggest that $\Delta\bar d(x)-\Delta\bar u(x)$ is
slightly negative, though the precision of the data is not enough for
confirming it.


title: Top-Quark Production and Decay in the MSSM

abstract:
  We review the features of top-quark decays and loop-induced effects in the
production cross section and CP-violating observables of e+e- -> t t-bar which
are specific to the R-parity conserving Minimal Supersymmetric Standard Model
(MSSM).


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

abstract:
  We show that the arguments forming the basis for the claim that the
conditions for total neutrino conversion derived and studied in detail in [1,2]
``are just the conditions of the parametric resonance of neutrino oscillations
supplemented by the requirement that the parametric enhancement be complete'',
given in [4] have flaws which make the claim physically questionable. We show
also that in the case of the transitions in the Earth of the
Earth-core-crossing solar and atmospheric neutrinos the peaks in the relevant
transitions probabilities $P_{a b}$, associated with the new conditions, $max
P_{a b} = 1$, are of physical relevance - in contrast to what is suggested in
[4]. Actually, the enhancement of $P_{a b}$ in any region of the corresponding
parameter space are essentially determined by these absolute maxima of $P_{a
b}$. We comment on few other aspects of the results derived in [1,2,3] which
have been misunderstood and/or misinterpreted in [4].


title:
Two-loop dimensional reduction and effective potential without
  temperature expansions

abstract:
  In many extensions of the Standard Model, finite temperature computations are
complicated by a hierarchy of zero temperature mass scales, in addition to the
usual thermal mass scales. We extend the standard thermal resummations to such
a situation, and discuss the 2-loop computations of the Higgs effective
potential, and an effective 3d field theory for the electroweak phase
transition, without carrying out high or low temperature expansions for the
heavy masses. We also estimate the accuracy of the temperature expansions
previously used for the MSSM electroweak phase transition in the presence of a
heavy left-handed stop. We find that the low temperature limit of dealing with
the left-handed stop is accurate up to surprisingly high temperatures.


title: Kalb-Ramond axion production in anisotropic string cosmologies

abstract:
  We compute the energy spectra for massless Kalb-Ramond axions in
four-dimensional anisotropic string cosmological models. We show that, when
integrated over directions, the four-dimensional anisotropic model leads to
infra-red divergent spectra similar to the one found in the isotropic case.


title: Systematics of q anti-q states in the (n,M^2) and (J,M^2) planes

abstract:
  In the mass region up to M < 2400 MeV we systematise mesons on the plots
(n,M^2) and (J,M^2), thus setting their classification in terms of n^{2S+1}L_J
q anti-q states. The trajectories on the (n,M^2)-plots are drawn for the
following (IJ^{PC})-states: a_0(10^{++}), a_1(11^{++}), a_2(12^{++}),
a_3(13^{++}), a_4(14^{++}), pi(10^{-+}), pi_2(12^{-+}), eta(00^{-+}),
eta_2(02^{-+})$, rho(11^{--}), f_0(00^{++}), f_2(02^{++}). All trajectories are
linear, with nearly the same slopes. At the (J,M^2)-plot we set out meson
states for leading and daughter trajectories: for pi, rho, a_1, a_2 and P'.


title: Gluelump spectrum in the QCD string model

abstract:
  Spectrum of gluons in the adjoint source field is computed analytically using
the QCD string Hamiltonian, containing only one parameter - string tension,
fixed by meson and glueball spectrum. Spin splitting is shown to be small. A
good agreement is observed with spatially generated gluelump states measured on
the lattice. Important role of gluelumps defining the behaviour of
field-strength correlators is stressed and correspondence with earlier
computations of the latter is established.


title:
Threshold expansion of Feynman diagrams within a configuration space
  technique

abstract:
  The near threshold expansion of generalized sunset-type (water melon)
diagrams with arbitrary masses is constructed by using a configuration space
technique. We present analytical expressions for the expansion of the spectral
density near threshold and compare it with the exact expression obtained
earlier using the method of the Hankel transform. We formulate a generalized
threshold expansion with partial resummation of the small mass corrections for
the strongly asymmetric case where one particle in the intermediate state is
much lighter than the others.


title: Theory of Heavy Baryon Decay

abstract:
  We discuss various topics in the theory of heavy baryon decays. Among these
are recent applications of the Relativistic Three Quark Model to semileptonic,
nonleptonic, one-pion and one-photon transitions among heavy baryons, new
higher order perturbative results on the correlator of two heavy baryon
currents and on the semi-inclusive decay $\Lambda_b \to X_c + D_s^{(*)-}$.


title:
Comment on Erratum: Multiparticle Bose-Einstein Correlations, Phys. Rev.
  C 61 029902(E)

abstract: The formulas in the above Erratum are corrected.


title: Effective Lagrangians in bound state calculations

abstract:
  In order to investigate specific aspects of bound state calculations in a
non-relativistic framework, we consider the energy-levels of a massive scalar
particle, which moves in an external field and interacts in addition with a
massless scalar particle. The discussion includes the following topics:
dimensionally regularized bound-state calculations, ultraviolet finiteness of
bound-state observables and their independence of the off-mass-shell behavior
of Green functions, non-renormalizable interactions, structure of the
non-relativistic two-point function, power counting and matching.


title: The Role of $B_s \to K \pi$ in Determining the Weak Phase $\gamma$

abstract:
  The decay rates for $B^0 \to K^+ \pi^-$, $B^+ \to K^0 \pi^+$, and the
charge-conjugate processes were found to provide information on the weak phase
$\gamma \equiv {\rm Arg}(V_{ub}^*)$ when the ratio $r$ of weak tree and penguin
amplitudes was taken from data on $B \to \pi \pi$ or semileptonic $B \to \pi$
decays. We show here that the rates for $B_s \to K^- \pi^+$ and $\bar B_s \to
K^+ \pi^-$ can provide the necessary information on $r$, and estimate the
statistical accuracy of forthcoming measurements at the Fermilab Tevatron.


title: Current Issues for Inflation

abstract:
  Brief review of some current topics, including gravitino creation and large
extra dimensions.


title:
Quark and Lepton Masses from a {\boldmath $U(1)\times Z_2$} Flavor
  Symmetry

abstract:
  We show that solutions for the masses and mixings of the quarks and leptons
based on a $U(1)\times Z_2$ horizontal symmetry are possible. The seesaw
mechanism is shown to work consistently in the presence of the discrete
symmetry. The discrete symmetry results in the phenomenologically useful
suppressions of elements of the Yukawa matrices. The quark and lepton masses,
the CKM mixing angles, and the neutrino mixing angles are accomodated at the
order of magnitude level.


title: Electroweak Baryogenesis: Concrete in a SUSY Model with a Gauge Singlet

abstract:
  SUSY models with a gauge singlet easily allow for a strong first order
electroweak phase transition (EWPT) if the vevs of the singlet and Higgs fields
are of comparable size. We discuss the profile of the stationary expanding
bubble wall and CP-violation in the effective potential, in particular
transitional CP-violation inside the bubble wall during the EWPT. The
dispersion relations for charginos contain CP-violating terms in the WKB
approximation. These enter as source terms in the Boltzmann equations for the
(particle--antiparticle) chemical potentials and fuel the creation of a baryon
asymmetry through the weak sphaleron in the hot phase. This is worked out for
concrete parameters.


title:
Achieving renormalization-scale- and scheme-independence in Pade-related
  resummation in QCD

abstract:
  Previously developed Pade-related method of resummation for QCD observables,
which achieves exact renormalization-scale-invariance, is extended so that the
scheme-invariance is obtained as well. The dependence on the leading scheme
parameter $c_2$ is eliminated by a variant of the method of the principle of
minimal sensitivity. The subleading parameter $c_3$ in the approximant is then
fixed in such a way that the correct known location of the leading infrared
renormalon pole is reproduced. Thus, $beta$-functions which go beyond the last
perturbatively calculated order in the observable are used. The
$\beta$-functions in the approximant are quasianalytically continued by Pade
approximants. Two aspects of nonperturbative physics are accounted for in the
presented resummation: a mechanism of quasianalytic continuation from the weak-
into the strong-coupling regime, and the (approximant-specific) contribution of
the leading infrared renormalon. The case of the Bjorken polarized sum rule is
considered as a specific example of how the method works.


title: Relativistic Corrections for Plarized J/\Psi-Production in b-quark decay

abstract:
  We analyse the structure of relativistic corrections in the inclusive
production of polarized $J/\Psi$ from b-quark decay. The analysis is performed
not only for the production channel in which the $c\bar c$ pair is a color
sinlet, but also for the channels in which the $c\bar c$ is a color octet. We
find that the correction in the color-singlet channel at the tree-level is
completely determined by the decay constant of $J/\Psi$, while in the
color-octet channels the corrections are characterized by three matrix elements
defined in NRQCD, whose numerical values are unknown. We discuss the impact of
these corrections on the polarized $J/\Psi$% -production, and the impact is so
significant that the predictions based on the analysis for the considered
process may be unreliable. Finally, we propose an integrated spin observable to
measure the polarization of $J/\Psi$%


title: Gluon Fragmentation into Glueballs and Hybrid Mesons

abstract:
  The constituent nature of candidate gluonic mesons can be studied by
comparing their production in quark and gluon jets. The production rate for
such mesons depends on the colour confinement processes at the end of the
perturbative evolution. Whereas we expect enhanced production of hybrids in the
fragmentation region of a gluon jet, the rate for glueballs depends on the
relative importance of colour triplet and colour octet neutralization. These
neutralization processes can be studied independently in events with large
rapidity gaps. If octet processes turn out important the recently suggested
lightest J^{PC}=0^{++} glueball with mass around 1000 MeV should become visible
already in the spectrum of the leading charged particle pairs.


title: On the effective light-cone QCD-Hamiltonian

abstract:
  Taking the effective interaction between a quark and an anti-quark from
previous work, the dependendence on a regularization scale is removed in line
with the renormalization group. In order to emphasize the essential point, the
full spinor interaction is replaced by a model which includes only the Coulomb
and the hyperfine interaction. By adjusting the effective quark masses, the
only free parameters of the theory, the mass and the size of the pion are
reproduced, as well as the mass of all other pseudo-scalar mesons. Estimates
for the vector mesons are close to the empirical values. The model exposes
screening rather than strict confinement. The ionization thresholds are in
general much larger than the pion mass.


title: Comment on "A New Dark Matter Candidate: Non-thermal Sterile Neutrinos"

abstract:
  I point out that the sterile neutrinos suggested as candidates of "cool" Dark
Matter will decay through their mixing with light neutrinos. This leads to an
upper bound of about 200 keV on the mass of the sterile neutrinos, but might
facilitate their detection.


title: SUSY Thresholds at a Muon Collider

abstract:
  One of the useful features of muon colliders is the naturally narrow spread
in beam energies. Measurements of threshold cross sections then become a prime
candidate for precision measurements of particle masses, widths, and couplings
as well as determining particle spin. We describe the potential for measuring
cross sections near threshold in supersymmetric theories.


title: Bulk Fields and Supersymmetry in a Slice of AdS

abstract:
  Five-dimensional models where the bulk is a slice of AdS have the virtue of
solving the hierarchy problem. The electroweak scale is generated by a ``warp''
factor of the induced metric on the brane where the standard model fields live.
However, it is not necessary to confine the standard model fields on the brane
and we analyze the possibility of having the fields actually living in the
slice of AdS. Specifically, we study the behaviour of fermions, gauge bosons
and scalars in this geometry and their implications on electroweak physics.
These scenarios can provide an explanation of the fermion mass hierarchy by
warp factors. We also consider the case of supersymmetry in the bulk, and
analyze the conditions on the mass spectrum. Finally, a model is proposed where
the warp factor generates a small (TeV) supersymmetry-breaking scale, with the
gauge interactions mediating the breaking to the scalar sector.


title: Scaling of the B and D meson spectrum in lattice QCD

abstract:
  We give results for the $B$ and the $D$ meson spectrum using NRQCD on the
lattice in the quenched approximation. The masses of radially and orbitally
excited states are calculated as well as $S$-wave hyperfine and $P$-wave fine
structure. Radially excited $P$-states are observed for the first time. Radial
and orbital excitation energies match well to experiment, as does the
strange-non-strange $S$-wave splitting. We compare the light and heavy quark
mass dependence of various splittings to experiment. Our $B$-results cover a
range in lattice spacings of more than a factor of two. Our $D$-results are
from a single lattice spacing and we compare them to numbers in the literature
from finer lattices using other methods. We see no significant dependence of
physical results on the lattice spacing.
  PACS: 11.15.Ha 12.38.Gc 14.40.Lb 14.40.Nd


title: Excited Heavy Baryons and Their Symmetries I: Formalism

abstract:
  This is the first of two papers to study a new emergent symmetry which
connects orbitally excited heavy baryons to the ground states in the combined
heavy quark and large $N_c$ limit. The existence of this symmetry is shown in a
model-independent way, and different possible realizations of the symmetry are
discussed. It is also proved that this emergent symmetry commutes with the
large $N_c$ spin-flavor symmetry.


title: Mesonic Anapole Form Factors of the Nucleons

abstract:
  The chiral quark model posits pseudoscalar and vector meson couplings to
constituent quarks. The parity violating meson-quark couplings lead to anapole
moments and form factors of the nucleons. These arise both as parity violating
meson loop fluctuations as well as exchange currents and polarization currents
that are induced by the parity violating interaction between quarks. Because of
cancellations between the different contributions the magnitude of the
calculated anapole moments is only of the order $\sim 10^{-8}$ and is
determined mainly by magnitude of the parity-violating meson-nucleon coupling
constants.


title: New Physics behind the Standard Model's door?

abstract:
  We review the main reasons pushing us beyond the SM and we argue in favor of
new physics at the electroweak scale (hence experimentally accessible at
present or near-future machines). We focus on the appealing possibility that
such new physics is given by a supersymmetric (SUSY) extension of the SM. We
discuss the minimal case, Constrained Minimal Supersymmetric SM, and more
general (maybe more natural) cases where some of the drastic assumptions of the
CMSSM are dropped. In particular, in these lectures we focus on CP violation
and its relation to flavor physics in the SUSY context. CP constrains the
low-energy SUSY extensions of the SM, but, at the same time, it provides new
powerful tool for indirect SUSY searches.


title:
Nonlinear evolution of the momentum dependent condensates in strong
  interaction: the ``pseudoscalar laser''

abstract:
  We discuss the relaxation of the scalar and pseudoscalar condensates after a
rapid quench from an initial state with fluctuations. If we include not only
the zero-mode but also higher modes of the condensates in the classical
evolution, we observe parametric amplification of those ``hard'' modes. Thus,
they couple nonlinearly to the ``soft'' modes. As a consequence, domains of
coherent pi-field emerge long after the initial spinodal decomposition. The
momentum-space distribution of pions emerging from the decay of that
momentum-dependent condensate is discussed.


title: Power-suppressed Thermal Effects from Heavy Particles

abstract:
  In quantum field theory, heavy particles with mass $M$ much greater than the
temperature $T$ give not only effects suppressed by the Boltzmann factor
$e^{-M/T}$, but also effects suppressed by powers of $T/M$. We show that
power-suppressed terms in equilibrium observables arise from effective
interactions among light particles due to virtual heavy particles. We study a
model introduced by Matsumoto and Yoshimura in which study a model introduced
by Matsumoto and Yoshimura in which heavy bosons interact only through a term
that allows pair annihilation into light particles. We construct an effective
Lagrangian for the light field by integrating out the heavy field, and use it
to calculate the leading power-suppressed terms in the energy density. The
thermal average of the Hamiltonian density for the heavy field includes a term
proportional to $T^6/M^2$, but we show that this term can be eliminated by a
field redefinition and therefore cannot have any physical significance.


title:
Nuclear Shadowing and Coherence Length for Longitudinal and Transverse
  Photons

abstract:
  Motivated by the recent results for DIS off nuclei from the HERMES experiment
we have performed a systematic study of shadowing for transverse and
longitudinal photons. We found that the coherence length which controls the
onset of nuclear shadowing at small x_{Bj} is much longer for longitudinal than
transverse photons, and is much shorter for shadowing of gluons. The light-cone
Green function approach we apply properly treats shadowing in the transition
region x_{Bj}>0.01. It also incorporates the nonperturbative effects and is
legitimate at small Q^2. We calculate nuclear shadowing and compare with data
from the HERMES and NMC experiments. Although we expect different nuclear
shadowing for longitudinal and transverse photons, numerically it cannot
explain the strong effect observed by the HERMES collaboration.