title:
Derivation of the Off-Shell O(q^4) Effective Pion-Nucleon Lagrangian
  Within Heavy Baryon Chiral Perturbation Theory

abstract: Paper withdrawn in favor of hep-ph/9909498


title: Comparative Energy Dependence of Proton and Pion Degradation in Diamond

abstract:
  A comparative theoretical study of the damages produced by protons and pions,
in the energy range 50 MeV - 50 GeV, in diamond, is presented. The
concentration of primary defects (CPD) induced by hadron irradiation is used to
describe material degradation. The CPD has very different behaviours for
protons and pions: the proton degradation is important at low energies and is
higher than the pion one in the whole energy range investigated, with the
exception of the Delta33 resonance region, where a large maximum of the
degradation exists for pions. In comparison with silicon, the most investigated
and the most studied material for detectors, diamond theoretically proves to be
one order of magnitude more resistant, both to proton and pion irradiation.


title: Scaling limits for the Lego discrepancy

abstract:
  For the Lego discrepancy with M bins, which is equivalent with a
chi^2-statistic with M bins, we present a procedure to calculate the moment
generating function of the probability distribution perturbatively if M and N,
the number of uniformly and randomly distributed data points, become large.
Furthermore, we present a phase diagram for various limits of the probability
distribution in terms of the standardized variable if M and N become infinite.


title:
Calculation of Electroproduction to NNLO and Precision Determination of
  $\alpha_s$

abstract:
  We use the known values of the two loop Wilson coefficients and the three
loop anomalous dimension matrix $\gamma(n)$ to perform a next-to-next-to
leading order (NNLO) calculation of $ep$ deep inelastic scattering. Because
$\gamma(n)$ is only known for a few values of $n$, the method of average
reconstruction has to be used, which leaves 102 effective experimental points,
for 12 parameters: the QCD mass $\Lambda$, and 11 initial values for the
moments of the structure functions. The data points spread in the range of
momenta $2.5 GeV^2\leq Q^2\leq 230 GeV^2$.
  The chi/dof decreases substantially when going from LO to NLO, and also from
NLO to NNLO (although only a little now) to $\chi/dof=79.2/(102-12)$.
  The favoured value of $\Lambda$ is $$\Lambda(n_f=4,3 {\rm loop})=282.7\pm35.1
MeV,$$ corresponding to the value of the coupling at the Z mass of
$$\alpha^{(\rm 3 loop)}_s(M_Z^2)=0.1172\pm0.0024. $$ The calculation, which
constitutes a very precise test of QCD, includes target mass corrections; the
error takes into account experimental errors and higher twist effects among
other estimated theoretical errors.


title: Supercooling in viscous hydrodynamics for QCD phase transition

abstract:
  First order quark hadron phase transition is considered in scaling
hydrodynamics including the Csernai-Kapusta model of nucleation of hadronic
bubbles leading to supercooling. The effect of viscosity on the entropy
production is studied in ideal as well as in viscous hydrodynamics with and
without supercooling. It is found that the excess entropy produced due to
supercooling depends weakly on viscosity.


title: Does the light and broad sigma(500) exist?

abstract:
  The lightest scalar and pseudoscalar nonets are discussed within the
framework of the broken U3$\times$U3 linear sigma model, and it is shown that
already at the tree level this model works remarkably well predicting scalar
masses and couplings not far from present experimental values, when all
parameters are fixed from the pseudoscalar masses and decay constants. It is
argued that this strongly suggests that the light and very broad $\sigma$
resonance exists near 500 MeV.


title: Anomalous pion decay revisited

abstract:
  An implicit four dimensional regularization is applied to calculate the
axial-vector-vector anomalous amplitude. The present technique always complies
with results of Dimensional Regularization and can be easily applied to
processes involving odd numbers of $\gamma_5$ matrices. This is illustrated
explicitely in the example of this letter.


title:
SUSY Higgs at the LHC: Large stop mixing effects and associated
  production

abstract:
  We revisit the effect of the large stop mixing on the decay and production of
the lightest SUSY Higgs at the LHC. We stress that whenever the inclusive
2-photon signature is substantially reduced, associated production, $Wh$ and
$t\bar t h$, with the subsequent decay of the Higgs into photons is enhanced
and becomes an even more important discovery channel. We also point out that
these reductions in the inclusive channel do not occur for the smallest Higgs
mass where the significance is known to be lowest. We show that in such
scenarios the Higgs can be produced in the decay of the heaviest stop. For not
too heavy masses of the pseudo-scalar Higgs where the inclusive channel is even
further reduced, we show that large stop mixing also allows the production of
the pseudo-scalar Higgs through stop decays. These large mixing scenarios
therefore offer much better prospects than previously thought. As a by-product
we have recalculated stop1-stop1-h production at the LHC and give a first
evaluation of stop1-stop1-Z.


title:
Neutrino spectrum, oscillation scenarios and neutrinoless double beta
  decay

abstract:
  We introduce the representation on one unitarity triangle of the constraints
resulting (1) from the interpretation of solar and atmospheric neutrino data in
terms of oscillations, and (2) from the search for neutrinoless double beta
decay. We show its use for the study of a nearly degenerate neutrino spectrum.
The representation shows clearly the particular cases when the neutrinoless
double beta decay rate can (or cannot) be small, that is: when the connection
of the decay rate with the neutrino spectrum is less (or more) direct. These
cases turn out to depend crucially on the scenario of oscillation (MSW
solutions, vacuum oscillations, averaged oscillations), and in particular on
the size of the mixing between the electron neutrino and the neutrino state
giving rise to atmospheric neutrino oscillations.


title: Weak Decays, CKM and CP Violation

abstract:
  I review several topics pertaining to Weak decays of b and c quarks,
including measurements of Vcb, |Vub/Vcb|, fDs and b->s gamma.


title:
Neutrino oscillation effect on the indirect signal of neutralino dark
  matter from the Earth core

abstract:
  We investigate the effect induced by neutrino oscillation on the dark matter
indirect detection signal which consists in a muon neutrino flux produced by
neutralino annihilation in the Earth core. We consider the neutrino oscillation
parameters relevant to the atmosferic neutrino deficit, both in the nu_mu ->
nu_tau and nu_mu -> nu_s cases.


title: Intermediate Scales in Supersymmetric GUTs: the Survival of the Fittest

abstract:
  We show that intermediate scales in supersymmetric grand unified theories may
exist naturally. Their origin is traced to the violation of the survival
principle: in supersymmetry internal symmetries often forbid cubic couplings in
the superpotential. This leads to a plethora of light supermultiplets whose
masses are generated only by higher dimensional operators and thus suppressed
by the cut-off scale. These new states often carry exotic quantum numbers and
may be, in some cases, accessible to experiments in the near future.


title: High Density QCD and Instantons

abstract:
  Instantons generate strong non-perturbative interactions between quarks. In
the vacuum, these interactions lead to chiral symmetry breaking and generate
constituent quark masses on the order of 300-400 MeV. The observation that the
same forces also provide attraction in the scalar diquark channel leads to the
prediction that cold quark matter is a color superconductor, with gaps as large
as $\sim$~100 MeV. We provide a systematic treatment of color superconductivity
in the instanton model. We show that the structure of the superconductor
depends on the number of flavors. In the case of two flavors, we verify the
standard scenario and provide an improved calculation of the mass gap. For
three flavors, we show that the ground state is color-flavor locked and
calculate the chiral condensate in the high density phase. We show that as a
function of the strange quark mass, there is a sharp transition between the two
phases. Finally, we go beyond the mean field approximation and investigate the
role of instanton-anti-instanton molecules, which -- besides superconducting
gap formation -- provide a competitive mechanism for chiral restoration at
finite density.


title:
Study of the determination of the SUGRA parameters using the ATLAS
  detector in the case of L-violating R parity breaking

abstract:
  Simulating pp collisions at LHC energies in the framework of the SUGRA model
and the detection of the produced leptons and jets by ATLAS we demonstrate that
a clean signature of SUSY can be obtained over a large domain of the parameter
space in the case of L-violating R parity breaking ($\lambda$ couplings). The
obtained signal allows the reconstruction of the SUSY particles and thereby the
precise determination of the model parameters $m_0, m_{1/2}, tan\beta$ and sign
$\mu$.


title:
Polarization Effects on the $e+e- \to W^+W^-$ process with Large Extra
  Dimensions

abstract:
  We study large extra dimension effects on the polarizations of the $W$ pair
and electron beam at the $e^+ e^-\to W^+ W^-$ process. It is shown that the
measurements of the cross section for transversely polarized $W$ pair with the
right-handed electron beam remarkably enhance the possibilities to see the low
scale quantum gravity effects. Higher Linear Collider bounds on the string
scale in this model can be obtained by using the left-handed electron beam.


title: Propagation of axions in a strongly magnetized medium

abstract:
  The polarization operator of an axion in a degenerate gas of electrons
occupying the ground-state Landau level in a superstrong magnetic field $H\gg
H_0=m_e^2c^3/e\hbar =4.41\cdot 10^{13}$ G is investigated in a model with a
tree-level axion-electron coupling. It is shown that a dynamic axion mass,
which can fall within the allowed range of values $(10^{-5} eV \lesssim
m_a\lesssim 10^{-2} eV)$, is generated under the conditions of strongly
magnetized neutron stars. As a result, the dispersion relation for axions is
appreciably different from that in a vacuum.


title: Bubble-nucleation rates for cosmological phase transitions

abstract:
  We estimate bubble-nucleation rates for cosmological phase transitions. We
concentrate on the evaluation of the pre-exponential factor, for which we give
approximate analytical expressions. Our approach relies on the use of a real
coarse-grained potential. We show how the coarse-graining scale can be
determined in the studies of high-temperature phase transitions. We discuss the
metastability bound on the Higgs-boson mass and the electroweak phase
transition. We find that the saddle-point approximation is reliable in the
first case and breaks down in the second case.


title: The Goldberger-Treiman Discrepancy

abstract:
  The Golberger- Treiman discrepancy is related to the asymptotic behaviour of
the pionic form factor of the nucleon obtained from baryonic QCD sum rules. The
result is .015<=Delta_{GT}<=.022


title:
The spin of the $f_J(1710)$ and new effects observed in the WA102
  experiment

abstract:
  A partial wave analysis of the centrally produced KK and pipi systems shows
that the fJ(1710) has J = 0. In addition, a study of central meson production
as a function of the difference in transverse momentum (dPT) of the exchanged
particles shows that undisputed qqbar mesons are suppressed at small dPT
whereas the glueball candidates are enhanced and that the production cross
section for different resonances depends strongly on the azimuthal angle
between the two outgoing protons.


title:
CP Asymmetries in B_d \to D^{*+}D^{*-} and B_s \to D^{*+}_s D^{*-}_s
  Decays: P-wave Dilution, Penguin and Rescattering Effects

abstract:
  Determination of the CP-violating parameters \sin 2\beta and \sin 2\beta' is
shown to be possible from B^0_d vs \bar{B}^0_d \to D^{*+}D^{*-} and B^0_s vs
\bar{B}^0_s \to D^{*+}_sD^{*-}_s decays {\it without} doing the angular
analysis. The P-wave dilution factors of these two asymmetries are found to be
0.89 and 0.90, respectively, using the factorization approximation and heavy
quark symmetry. The penguin-induced corrections amount to about 2% and 3% in
the corresponding B_d and B_s channels. Final-state rescattering effects could
be handled by detecting the neutral modes B^0_d and \bar{B}^0_d \to
D^{*0}\bar{D}^{*0}.


title: Coherent Interactions with heavy ions at CMS

abstract:
  Due to coherence, there are strong electromagnetic fields of short duration
in very peripheral collisions. They give rise to photon-photon and
photon-nucleus collisions with high flux up to an invariant mass region
hitherto unexplored experimentally. After a general survey photon-photon
luminosities in relativistic heavy ion collisions are discussed. Special care
is taken to include the effects of strong interactions and nuclear size. Then
photon-photon physics at various invariant mass scales is discussed. Invariant
masses of up to about 100 GeV can be reached at LHC, and in addition the
potential for new physics is available. Photonuclear reactions and other
important background effects, especially diffractive processes are also
discussed. Lepton-pair production, especially electron-positron pair production
is copious. Due to the strong fields there will be new phenomena, especially
multiple e+e- pair production.


title: Proton polarizability and the Lamb shift in muonic hydrogen

abstract:
  The proton structure and proton polarizability corrections to the Lamb shift
of electronic hydrogen and muonic hydrogen were evaluated on the basis of
modern experimental data on deep inelastic structure functions. Numerical value
of proton polarizability contribution to (2P-2S) Lamb shift is equal to 4.4
GHz.


title: Radiative Leptonic $B_c$ Decays

abstract:
  We analyze the radiative leptonic $B_c$ decay mode: $B_c \to \ell \nu \gamma$
($\ell=e, \mu$) using a QCD-inspired constituent quark model. The prediction:
${\cal B}(B_c \to \ell \nu \gamma)\simeq 3 \times 10^{-5}$ makes this channel
experimentally promising in view of the large number of $B_c$ mesons which are
expected to be produced at the future hadron facilities.


title:
Quark masses and mixings in the standard model with heavy vector-like
  families

abstract:
  The extension of the standard model with pairs of the vector-like families is
studied. The quark mixing matrices for the left- and right-handed charged
currents, as well as those for the flavour changing neutral currents, the Z and
Higgs mediated, are found. Both the model independent parametrization for an
arbitrary case and an explicit realization for the case with one pair of the
heavy vector-like families are presented. The extension opens new prospects for
studying deviations from the standard model in the future experiments at high
energies.


title:
Proposing "b-Parity" - a New Approximate Quantum Number in Inclusive
  b-jet Production - as an Efficient Probe of New Flavor Physics

abstract:
  We consider the inclusive reaction \ell^+ \ell^- -> nb +X (n = number of
b-jets) in lepton colliders for which we propose a useful approximately
conserved quantum number b_P=(-1)^n that we call b-Parity (b_P). We make the
observation that the Standard Model (SM) is essentially b_P-even since SM
b_P-violating signals are necessarily CKM suppressed. In contrast new flavor
physics can produce b_P=-1 signals whose only significant SM background is due
to b-jet misidentification. Thus, we show that b-jet counting, which relies
primarily on b-tagging, becomes a very simple and sensitive probe of new flavor
physics (i.e., of b_P-violation).


title: Up-Down Unification, Neutrino Masses and Rare Lepton Decays

abstract:
  In a recent paper, we showed that tree level up-down unification of fermion
Yukawa couplings is a natural consequence of a large class of supersymmetric
models. They can lead to viable quark masses and mixings for moderately large
values of $\tan\beta$ with interesting and testable predictions for CP
violation in the hadronic sector. In this letter, we extend our discussion to
the leptonic sector focusing on one particular class of these models, the
supersymmetric left-right model with the seesaw mechanism for neutrino masses.
We show that fitting the solar and the atmospheric neutrino data considerably
restricts the Majorana-Yukawa couplings of the leptons in this model and leads
to predictions for the decay $\tau\to \mu +\gamma$, which is found to be
accessible to the next generation of rare decay searches. We also show that the
resulting parameter space of the model is consistent with the requirements of
generating adequate baryon asymmetry through lepton-number violating decays of
the right-handed neutrino.


title:
On the muon anomalous magnetic moment in models with a superlight
  gravitino

abstract:
  We perform a general analysis of the contributions to the muon anomalous
magnetic moment in models with a superlight gravitino. We discuss the
interpretation and the phenomenological implications of the results. We find
that present constraints on the model parameters are comparable and
complementary to the ones coming from collider searches and from perturbative
unitarity. However, the Brookhaven E821 experiment will probe large unexplored
regions of parameter space.


title: Status of the BFKL Resummation Program

abstract:
  I discuss the calculation of the next-to-leading logarithmic (NLL)
corrections to the BFKL resummation, as well as some of the issues that arise
in this formalism at NLL. In particular I consider the large size and apparent
instability of the corrections, and I address some of the attempts to
understand and tame them.


title: Neutrinos,Cosmology and Astrophysics

abstract:
  We review bounds on neutrino properties, in particular on their masses,
coming mostly from cosmology, and also from astrophysics.


title: The Strange Quark Mass From Finite Energy Sum Rules

abstract:
  The strange quark mass is determined from a study of the correlator of the
divergence of the strange vector current using a family of finite energy sum
rules recently shown to be very accurately satisfied in the isovector vector
channel. It is shown that the match between the OPE and hadronic
representations for the sum rules employed is extremely good once one fixes the
overall scale, (m_s-m_u), which normalizes the OPE side. A value $m_s=115\pm 8$
MeV at a scale 2 GeV, corresponding to $m_s=159\pm 11$ MeV at a scale 1 GeV, is
obtained, with theoretical and experimental uncertainties contributing roughly
equally to the combined error.


title: The parameter space for tree-level hybrid inflation

abstract:
  In a large region of parameter space, the tree-level hybrid inflation model
is likely to be be invalidated by loop corrections. In particular, this is
likely to be the case if both quartic couplings are of order unity, as is often
supposed. It is likely also to be the case if there is an ultra-violet cutoff
far below the Planck scale, ($\luv\lsim 10^9\GeV(V_0^{1/4}/1\MeV)^{2/5}$, where
$V_0$ is the height of the potential) unless one allows field values bigger
than the cutoff.


title: Inflation, the mu Problem and Maximal nu_mu-nu_tau Mixing

abstract:
  A supersymmetric model based on a left-right symmetric gauge group, which
`naturally' leads to hybrid inflation, is studied. It is shown that the mu
problem can be easily solved in this model. The observed baryon asymmetry of
the universe is produced via a primordial leptogenesis. For masses of nu_mu,
nu_tau from the small angle MSW resolution of the solar neutrino problem and
SuperKamiokande, maximal nu_mu-nu_tau mixing can be achieved. The required
values of the relevant parameters are, however, quite small.


title:
Hadronic contribution to $\alpha(M_Z^2)$ and the anomalous magnetic
  moment of the muon

abstract:
  In this contribution recent developments are discussed which lead to a
significant reduction of the error for $\alpha(M_Z^2)$ and $(g-2)_\mu$.


title: On the decay of neutral kaons

abstract:
  It is shown that the data on the decay of neutral kaons may be explained
without CP-violation.


title:
Transverse Spin / Transverse Momentum Analogy and Gauge Invariance of
  Deeply Virtual Compton Scattering

abstract:
  Using the similarity between twist 3 contributions to transverse spin for
usual parton distributions and transverse momentum for non-diagonal parton
distributions, we determine for the simple case of a scalar (pion, $He^4$)
target the linear in transverse momentum twist-3 contribution to Deeply Virtual
Compton amplitude. This allows to write a gauge invariant amplitude for this
non-forward process.


title: Spin Structure of Nucleon and Equivalence Principle

abstract:
  The partition of nucleon spin between total angular momenta of quarks and
gluons is described by the energy momentum tensor formfactors manifested also
in the nucleon scattering by weak classical gravitational field. Natural
generalization of equivalence principle is resulting in the identically zero
"Anomalous gravitomagnetic moment" being the straightforward analog of its
electromagnetic counterpart. This, in turn, means the equal partition of
momentum and total angular momentum, anticipated earlier.}


title: Coulomb Gas Representation of Low Energy QCD

abstract:
  A novel Coulomb gas (CG) description of low energy $QCD_4$, based on the dual
transformation of the QCD effective chiral Lagrangian, is constructed. The CG
is found to contain several species of charges, one of which is fractionally
charged and can be interpreted as instanton-quarks. The creation operator which
inserts a pseudo-particle in the CG picture is explicitly constructed and
demonstrated to have a non-zero vacuum expectation value. The Wilson loop
operator as well as the creation operator for the domain wall in the CG
representation is also constructed.


title:
Phenomenological consequences of supersymmetry with anomaly-induced
  masses

abstract:
  In the supersymmetric standard model there exist pure gravity contributions
to the soft mass parameters which arise via the superconformal anomaly. We
consider the low-energy phenomenology with a mass spectrum dominated by the
anomaly-induced contributions. In a well-defined minimal model we calculate
electroweak symmetry breaking parameters, scalar masses, and the full one-loop
splitting of the degenerate Wino states. The most distinctive features are
gaugino masses proportional to the corresponding gauge coupling beta-functions,
the possibility of a Wino as the lightest supersymmetric particle, mass
degeneracy of sleptons, and a very massive gravitino. Unique signatures at
high-energy colliders include dilepton and single lepton final states,
accompanied by missing energy and displaced vertices. We also point out that
this scenario has the cosmological advantage of ameliorating the gravitino
problem. Finally, the primordial gravitino decay can produce a relic density of
Wino particles close to the critical value.


title: A Real CKM Matrix and Physics Beyond the Standard Model

abstract:
  We study the possible existence of a real Cabibbo-Kobayashi-Maskawa (CKM)
matrix, with CP violation originating from physics beyond the standard model
(SM). We show that present experimental data allow for a real CKM matrix
provided that new physics also contributes to Delta m_{B_d} by at least 20% of
the SM contribution (for rho > 0), besides generating CP violation in the kaon
sector. The naturalness of a real CKM matrix is studied within the framework of
general multi-Higgs-doublet models with spontaneous CP violation. As an
example, we discuss a specific two-Higgs-doublet model and its implications for
CP asymmetries in non-leptonic neutral B-meson decays.


title:
Tests of Low Scale Gravity via Gauge Boson Pair Production in $\gamma
  \gamma$ Collisions

abstract:
  Arkani-Hamed, Dimopoulos and Dvali have recently proposed that gravity may
become strong at energies near 1 TeV thus removing the hierarchy problem. This
scenario can be tested in several ways at present and future colliders. In this
paper we examine the exchange of towers of Kaluza-Klein gravitons and their
influence on the production of pairs of massive gauge bosons in $\gamma \gamma$
collisions. These tower exchanges are shown to lead to a new dimension-8
operator that can significant alter the Standard Model expectations for these
processes. The role of polarization for both the initial state photons and the
final state gauge bosons in improving sensitivity to graviton exchange is
emphasized. We find that the discovery reach for graviton tower exchange in the
$\gamma \gamma \to W^+W^-$ channel to be significantly greater than for any
other process so far examined.


title:
Predictions for Higgs and SUSY Higgs properties and their signatures at
  the Hadron Colliders

abstract:
  In this talk I present a discussion of the theoretical bounds on the mass of
the Higgs in the Standard Model (SM) as well as in the Minimal Supersymmetric
Standard Model (MSSM). Then I will point out a few facts about the couplings of
scalars that are relevant for its search at hadronic colliders. After that I
discuss the search possibilities at the Tevatron and the LHC, paying special
attention to the issue of how well one can establish the quantum numbers and
the couplings of the Higgs, when (if) it is discovered.


title: Neutrino Masses and Bimaximal Mixing

abstract:
  Solar and atmospheric neutrino anomalies are described by bimaximal mixing of
three neutrinos. Neutrino oscillations in appearance nu_e <--> nu_mu,nu_tau and
in disappearance nu_e long baseline and atmospheric experiments are sensitive
to deviations from the ideal bimaximal mixing. It is suggested that these
deviations may be dominated by a rotation in the electron--muon plane of the
generation space. Simple seesaw models are described supporting this idea. The
rotation angle is estimated from Fritzsch's relation. Predictions are presented
for oscillations in long baseline experiments, for solar neutrinos, and for the
rates of neutrinoless double beta decays.


title: Four Dimensionality in Non-compact Kaluza-Klein Model

abstract:
  Five dimensional model with extended dimensions investigated. It is shown
that four dimensionality of our world is the result of stability requirement.
Extra component of Einstein equations giving trapping solution for matter
fields coincides with the one of conditions of stability.


title:
Search for the Neutrino Magnetic Moment in the Non-Equilibrium Reactor
  Antineutrino Energy Spectrum

abstract:
  We study the time evolution of the typical nuclear reactor antineutrino
energy spectrum during reactor ON period and the decay of the residual
antineutrino spectrum after reactor is stopped. We find that relevant
variations of the soft recoil electron spectra produced via weak and magnetic
${\widetilde {\nu}}_{e},e$ scattering process can play a signigicant role in
the current and planned searches for the neutrino magnetic moment at reactors.


title: How to Generate Four-Fermion Phase Space

abstract:
  We present a scheme for integrating the matrix element of an arbitrary
e^+e^-\to f_1f_2\bar f_3\bar f_4 process over the complete four-fermion phase
space, or its any part, by means of the Monte Carlo technique. The presented
algorithm has been successfully implemented in the KORALW Monte Carlo code.


title: Flavoured multiskyrmions

abstract:
  Static properties of multiskyrmions with baryon numbers up to 8 are
calculated starting from recently given rational map ansaetze. The spectra of
baryonic systems with strangeness, charm and bottom are estimated within a
"rigid oscillator" version of the bound state soliton model. It is suggested
that the recently observed negatively charged nuclear fragment can be
considered as quantized strange multiskyrmion with baryon number 6 or 7 and
large value of strangeness. In agreement with previous observation, it is
argued that baryonic systems with charm or bottom quantum numbers have more
chances to be bound with respect to strong interactions than strange baryonic
systems.


title: On Large-Angle Bhabha Scattering at LEP

abstract:
  The theoretical accuracy of the program TOPAZ0 in the large-angle Bhabha
channel is estimated. The physical error associated with the full Bhabha cross
section and its forward and backward components separately is given for some
event selections and several energy points of interest for LEP1 physics, both
for the $s$ and non-$s$ contributions to the cross section.


title: Phenomenology of light Higgs bosons in supersymmetric left-right models

abstract:
  We carry out a detailed analysis of the light Higgs bosons in supersymmetric
left-right models (SLRM). This includes models with minimal particle content
and those with additional Higgs superfields. We also consider models with
non-renormalizable higher-dimensional terms. We obtain an upper bound on the
mass of the lightest CP-even neutral Higgs boson in these models. The upper
bound depends only on the gauge couplings, and the vacuum expectation values of
those neutral Higgs fields which control the spontaneous breakdown of the
$SU(2)_L \times U(1)_Y$ gauge symmetry. We calculate the one-loop radiative
corrections to this upper bound, and evaluate it numerically in the minimal
version of the supersymmetric left-right model. We consider the couplings of
this lightest CP-even Higgs boson to the fermions, and show that in a
phenomenologically viable model the branching ratios are similar to the
corresponding branching ratios in the minimal supersymmetric standard model
(MSSM). We then study the most promising particle for distinguishing the SLRM
from other models, namely the doubly charged Higgs boson. We obtain the mass of
this doubly charged Higgs boson in different types of supersymmetric left-right
models, and discuss its phenomenology.


title: Boson Interferometry in High Energy Physics

abstract:
  Intensity interferometry and in particular that due to Bose Einstein
correlations (BEC) constitutes at present the only direct experimental method
for the determination of sizes and lifetimes of sources in particle and nuclear
physics. The measurement of these is essential for an understanding of the
dynamics of strong interactions which are responsible for the existence and
properties of atomic nuclei. Moreover a new state of matter, quark matter, in
which the ultimate constituents of matter move freely, is within the reach of
present accelerators or those under construction. The confirmation of the
existence of this new state is intimately linked with the determination of its
space-time properties. Furthermore BEC provides information about quantum
coherence which lies at the basis of the phenomenon of Bose-Einstein
condensation seen in many chapters of physics. Coherence and the associated
classical fields are essential ingredients in modern theories of particle
physics including the standard model. Last but not least besides this
"applicative" aspect of BEC, this effect has implications for the foundations
of quantum mechanics including the understanding of the concept of ``identical
particles". Recent theoretical developments in BEC are reviewed and their
application in high energy particle and heavy-ion reactions is analyzed. The
treated topics include: a) a comparison between the wave-function approach and
the space-time approach based on classical currents, which predicts
"surprising" particle anti-particle BEC b) the study of final state
interactions c) the use of hydrodynamics d) the relation between correlations
and multiplicity distributions.


title: Dynamical Viscosity of Nucleating Bubbles

abstract:
  We study the viscosity corrections to the growth rate of nucleating bubbles
in a first order phase transition in scalar field theory. We obtain the
non-equilibrium equation of motion of the coordinate that describes small
departures from the critical bubble and extract the growth rate consistently in
weak coupling and in the thin wall limit. Viscosity effects arise from the
interaction of this coordinate with the stable quantum and thermal fluctuations
around a critical bubble. In the case of 1+1 dimensions we provide an estimate
for the growth rate that depends on the details of the free energy functional.
In 3+1 dimensions we recognize robust features that are a direct consequence of
the thin wall approximation and give the leading viscosity corrections.These
are long-wavelength hydrodynamic fluctuations that describe surface waves,
quasi-Goldstone modes which are related to ripples on interfaces in phase
ordered Ising-like systems. We discuss the applicability of our results to
describe the growth rate of hadron bubbles in a quark-hadron first order
transition.


title: Quality of Variational Trial States

abstract:
  Besides perturbation theory (which clearly requires the knowledge of the
exact unperturbed solution), variational techniques represent the main tool for
any investigation of the eigenvalue problem of some semibounded operator H in
quantum theory. For a reasonable choice of the employed trial subspace of the
domain of H, the lowest eigenvalues of H usually can be located with acceptable
precision whereas the trial-subspace vectors corresponding to these eigenvalues
approximate, in general, the exact eigenstates of H with much less accuracy.
Accordingly, various measures for the accuracy of the approximate eigenstates
derived by variational techniques are scrutinized. In particular, the matrix
elements of the commutator of the operator H and (suitably chosen) different
operators with respect to degenerate approximate eigenstates of H obtained by
variational methods are proposed as new criteria for the accuracy of
variational eigenstates. These considerations are applied to precisely that
Hamiltonian for which the eigenvalue problem defines the well-known spinless
Salpeter equation. This bound-state wave equation may be regarded as (the most
straightforward) relativistic generalization of the usual nonrelativistic
Schroedinger formalism, and is frequently used to describe, e.g., spin-averaged
mass spectra of bound states of quarks.


title: Inflation in Supersymmetric Cosmic String Theories

abstract:
  We examine a non-Abelian SUSY $SU(2) \times U(1)$ gauge theory and a SUSY
U(1) theory originally used to investigate the microphysics of cosmic strings
in supersymmetric theories. We show that both theories automatically include
hybrid inflation. In the latter theory we use a $D$ term to break the symmetry.
SUSY is broken during inflation and restored afterwards. Cosmic strings are
formed at the end of inflation. The temperature anisotropy is calculated and
found to vary as $(M_{GUT}/M_P)^2$.


title: MSSM Predictions for the Electric Dipole Moment of the $^{199}$Hg Atom

abstract:
  The Minimal Supersymmetric Standard Model can possess several CP-violating
phases beyond the conventional Cabibo-Kobayashi-Maskawa phase. We calculate the
contribution of these phases to T-violating nuclear forces. These forces induce
a Schiff moment in the $^{199}$Hg nucleus, which is strongly limited by
experiments aimed at the detection of the electric dipole moment of the mercury
atom. The result for $d_{Hg}$ is found to be very sensitive to the CP-violating
phases of the MSSM and the calculation carries far fewer QCD uncertainties than
the corresponding calculation of the neutron EDM. In certain regions of the
MSSM parameter space, the limit from the mercury EDM is stronger than previous
constraints based on either the neutron or electron EDMs. We present combined
constraints from the mercury and electron EDMs to limit both CP-violating
phases of the MSSM. We also present limits in mSUGRA models with unified
gaugino and scalar masses at the GUT scale.


title: Casimir-Polder forces in the presence of the cosmic photon heat bath

abstract:
  We study the effect of a photon background at finite temperature $T$ on the
Van der Waals interactions among neutral bodies. It turns out that the
long-range Casimir-Polder force is unaffected for distances much less than
$T^{-1}$ and strongly enhanced for distances much above $T^{-1}$.


title: Naturalness of nearly degenerate neutrinos

abstract:
  If neutrinos are to play a relevant cosmological role, they must be
essentially degenerate. We study whether radiative corrections can or cannot be
responsible for the small mass splittings, in agreement with all the available
experimental data. We perform an exhaustive exploration of the bimaximal mixing
scenario, finding that (i) the vacuum oscillations solution to the solar
neutrino problem is always excluded; (ii) if the mass matrix is produced by a
see-saw mechanism, there are large regions of the parameter space consistent
with the large angle MSW solution, providing a natural origin for the $\Delta
m^2_{sol} << \Delta m^2_{atm}$ hierarchy; (iii) the bimaximal structure becomes
then stable under radiative corrections. We also provide analytical expressions
for the mass splittings and mixing angles and present a particularly simple
see-saw ansatz consistent with all observations.


title: Detection of Long-Lived Particles in Run II with D0

abstract:
  We discuss possibilities of detecting neutral and charged long-lived
particles with the upgraded D0 detector in Run II of the Fermilab Tevatron
accelerator, using photon pointing, dE/dx, and time-of-flight techniques. Such
particles appear in many SM extensions, e.g., Gauge Mediated SUSY. This work
has been done in the context of the BTMSSM Working group of the Run II
SUSY/Higgs Workshop at Fermilab.


title: Search for R-parity Violating SUSY in Run 2 at D0

abstract:
  We present a study of sensitivity of the R-parity violating SUSY searches
with the upgraded D0 detector in Run II of the Fermilab Tevatron, within a
SUGRA framework. We considered the lightest neutralino as an LSP that decays
into a lepton and slepton (R-parity violating decay), resulting in 2e + \ge 4
jets or 2\mu + \ge 4 jets final state. The analysis, based on scaling of the
Run I results, shows that squarks and gluinos with masses up to about 0.6 TeV
could be probed with 2 fb^-1 of Run II data. This work has been done in the
context of the BTMSSM Working Group of the Run II SUSY/Higgs Workshop at
Fermilab.


title: Nonresonant Semileptonic Heavy Quark Decay

abstract:
  In both the large N_c limit and the valence quark model, semileptonic decays
are dominated by resonant final states. Using Bjorken's sum rule in an
"unquenched" version of the quark model, I demonstrate that in the heavy quark
limit nonresonant final states should also be produced at a significant rate.
By calculating the individual strengths of a large number of exclusive two-body
nonresonant channels, I show that the total rate for such processes is highly
fragmented. I also describe some very substantial duality-violating suppression
factors which reduce the inclusive nonresonant rate to a few percent of the
total semileptonic rate for the finite quark masses of B decay, and comment on
the importance of nonresonant decays as testing grounds for very basic ideas on
the structure, strength, and significance of the quark-antiquark sea and on
quark-hadron duality in QCD.


title: Seasonal Variations of the 7Be Solar Neutrino Flux

abstract:
  Measuring the 7Be solar neutrino flux is crucial towards solving the solar
neutrino puzzle. The Borexino experiment, and possibly the KamLAND experiment,
will be capable of studying the 7Be neutrinos in the near future. We discuss
(1) how the seasonal variation of the Borexino and KamLAND data can be used to
measure the 7Be solar neutrino flux in a background independent way and (2) how
anomalous seasonal variations might be used to discover vacuum neutrino
oscillations, independent of the solar model and the measurement of the
background. In particular, we find that, after three years of Borexino or
KamLAND running, vacuum neutrino oscillations can be either established or
excluded for almost all values of (sin^2 2 theta, Delta m^2) preferred by the
Homestake, GALLEX, SAGE, and Super-Kamiokande data. We also discuss how well
seasonal variations of the data can be used to measure (sin^2 2 theta, Delta
m^2) in the case of vacuum oscillations.


title:
Nonperturbative contribution to the
  Dokshitzer-Gribov-Lipatov-Altarelli-Parisi and Gribov-Levin-Ryskin equation

abstract:
  By studying the nonperturbative contribution to the
Dokshitzer-Gribov-Lipatov-Altarelli-Parisi and Gribov-Levin-Ryskin equation, it
is found that (i) the nonperturbative contribution suppresses the evolution
rate at the low $Q^2$, small-x region; (ii) the nonperturbative contribution
weakens the shadowing effect. The method in this paper suggests a smooth
transition from the low $Q^2$ ("soft"), where nonperturbative contribution
dominates, to the large $Q^2$ ("hard") region, where the perturbative
contribution dominates and the nonperturbative contribution can be neglected.
  PACS numbers:12.38.Aw, 13.60.Hb


title:
Anomalous couplings of vector bosons and the decay $H \longrightarrow
  \gamma \gamma$: Dimensional regularization versus momentum cutoff

abstract:
  As an illustration of general principles, the $W$-boson loop contribution to
the amplitude for the decay $H\to \gamma \gamma$ is calculated within a
specific model for the effective lagrangian describing the anomalous gauge
boson couplings. Different approaches to the dependence of the result on the
scale of new physics $\Lambda$ are briefly discussed.


title: Predictions for dijet production in DIS using small x dynamics

abstract:
  We study the properties of dijet production in deep inelastic scattering
using a unified BFKL/DGLAP framework, which includes important subleading ln
(1/x) contributions. We calculate the azimuthal decorrelation between the jets.
We compute the cross section for dijet production as a function of Q^2 and the
jet transverse momentum, as well as calculate the total dijet rate. We compare
the predictions with HERA data.


title: Test of CPT symmetry in cascade decays

abstract:
  Cascade mixing provides an elegant place to study the $B^0-\bar{B^0}$ mixing.
We use this idea to study the CPT violation caused by $B^0-\bar{B^0}$ mixing.
An approximation method is adopted to treat the two complex $B^0-\bar{B^0}$
mixing parameters $\theta$ and $\phi$. A procedure to extract the parameters
$\theta$ and $\phi$ is suggested. The feasibility of exploring the CPT
violation and determining of $\theta$ and $\phi$ in the future B-factories and
LHC-B is discussed.


title: Parton Saturation at Small x and in Large Nuclei

abstract:
  Quark and gluon distributions in the light-cone wavefunction of a high energy
hadron or nucleus are calculated in the saturation regime. One loop
calculations are performed explicitly using the equivalence between the parton
distribution in the light-cone wavefunction and the production distribution of
that parton in a current-nucleon (nucleus) scattering. We argue that, except
for some overall numerical factors, the Weizsacker- Williams wavefunction
correctly gives the physics of the gluon distribution in a light-cone
wavefunction.


title: Proton Spin Based On Chiral Dynamics

abstract:
  Chiral spin fraction models agree with the proton spin data only when the
chiral quark-Goldstone boson couplings are pure spinflip. For axial-vector
coupling from soft-pion physics this is true for massless quarks but not for
constituent quarks. Axial-vector quark-Goldstone boson couplings with {\bf
constituent} quarks are found to be inconsistent with the proton spin data.


title: The Dualized Standard Model and its Applications---an Interim Report

abstract:
  Based on a nonabelian generalization of electric-magnetic duality, the
Dualized Standard Model (DSM) suggests a natural explanation for exactly 3
generations of fermions as the `dual colour' $\widetilde{SU}(3)$ symmetry
broken in a particular manner. The resulting scheme then offers on the one hand
a fermion mass hierarchy and a perturbative method for calculating the mass and
mixing parameters of the Standard Model fermions, and on the other testable
predictions for new phenomena ranging from rare meson decays to ultra-high
energy cosmic rays. Calculations to 1-loop order gives, at the cost of
adjusting only 3 real parameters, values for the following quantities all
(except one) in very good agreement with experiment: the quark CKM matrix
elements $|V_{rs}|$, the lepton CKM matrix elements $|U_{rs}|$, and the second
generation masses $m_c, m_s, m_\mu$. This means, in particular, that it gives
near maximal mixing $U_{\mu3}$ between $\nu_\mu$ and $\nu_\tau$ as observed by
SuperKamiokande, Kamiokande and Soudan, while keeping small the corresponding
quark angles $V_{cb}, V_{ts}$. In addition, the scheme gives (i) rough
order-of-magnitude estimates for the masses of the lowest generation, (ii)
predictions for low energy FCNC effects such as $K_L \to e \mu$, (iii) a
possible explanation for the long-standing puzzle of air showers beyond the GZK
cut-off. All these together, however, still represent but a portion of the
possible physical consequences derivable from the DSM scheme the majority of
which are yet to be explored.


title: Gluelump Spectrum in the Bag Model

abstract:
  We explore the ordering of the lowest levels in a simple bag model of the
``gluelump'' of Michael and also discuss, again within the context of the bag
model, the related problem of hybrid potentials in the limit of very small
spacing between quark and anti-quark sources.


title: Standard Model Confronting New Results for epsilon'/epsilon

abstract:
  We analyze the CP violating ratio \epe=epsilon'/epsilon in the Standard Model
in view of the new KTeV results. We review the present status of the most
important non-perturbative parameters B_6, B_8, B_K and of the strange quark
mass m_s. We also briefly discuss the issues of final state interactions and
renormalization scheme dependence. Updating the values of the CKM parameters,
of m_t and Lambda (MSbar) and using Gaussian errors for the experimental input
and flat distributions for the theoretical parameters we find \epe
substantially below the NA31 and KTeV data: \epe= (7.7^{+6.0}_{-3.5}) 10^{-4}
and \epe= (5.2^{+4.6}_{-2.7}) 10^{-4} in the NDR and HV renormalization schemes
respectively. A simple scanning of all input parameters gives on the other hand
1.05 10^{-4} < \epe < 28.8 10^{-4} and 0.26 10^{-4} < \epe < 22.0 10^{-4}
respectively. Analyzing the dependence on various parameters we find that only
for extreme values of B_6, B_8 and m_s and suitable values of CKM parameters
and Lambda(MSbar), the ratio \epe can be made consistent with data. We analyze
the impact of these data on the lower bounds for Im(V_{td}V_{ts}^*), Br(K_L to
pi^0 nu barnu), Br(K_L to pi^0e^+e^-)_{dir} and on tan(beta) in the Two Higgs
Doublet Model II.


title:
Warm Inflation in the Adiabatic Regime- a Model, an Existence Proof for
  Inflationary Dynamics in Quantum Field Theory

abstract:
  Warm inflation is examined in a multi-field model. Solutions are obtained for
expansion e-folds and scalar density perturbations. Nonequilibrium dynamics is
restricted to a regime that is displaced only slightly from thermal equilibrium
and in which all macroscopic motion is adiabatic. In such a regime,
nonequilibrium dynamics is well defined, provided macroscopic motions that
displace the thermal equilibrium state occur sufficiently slow. The solution
has adjustable parameters that permit observational consistency with respect to
expansion e-folds and density perturbations in the full adiabatic regime, thus
insuring a valid solution regime. For particle physics, the model is
nonstandard since it requires a large number of fields, $> 10^4$. A particle
physics/string interpretation of the model and solutions is discussed, which
can accommodate the large field number requirement.


title: The Ubiquitous Inflaton in String-Inspired Models

abstract:
  A string theory based inflationary model is developed where the inflaton
interacts with a multitude of massive string level states causing dissipation
of vacuum energy. Inflation terminates in a warm Universe without the need for
reheating.


title: Cosmological implications of a Relic Neutrino Asymmetry

abstract:
  We consider some consequences of the presence of a cosmological lepton
asymmetry in the form of neutrinos. Relic neutrino degeneracy enhances the
contribution of massive neutrinos to the present energy density of the
Universe, and modifies the power spectrum of radiation and matter. Comparing
with current observations of cosmic microwave background anisotropies and large
scale structure, we derive some constraints on the neutrino degeneracy and on
the spectral index in the case of a flat Universe with a cosmological constant.


title: Higgs Boson Bounds in Three and Four Generation Scenarios

abstract:
  In light of recent experimental results, we present updated bounds on the
lightest Higgs boson mass in the Standard Model (SM) and in the Minimal
Supersymmetric extension of the Standard Model (MSSM). The vacuum stability
lower bound on the pure SM Higgs boson mass when the SM is taken to be valid up
to the Planck scale lies above the MSSM lightest Higgs boson mass upper bound
for a large amount of SUSY parameter space. If the lightest Higgs boson is
detected with a mass M_{H} < 134 GeV (150 GeV) for a top quark mass M_{top} =
172 GeV (179 GeV), it may indicate the existence of a fourth generation of
fermions. The region of inconsistency is removed and the MSSM is salvagable for
such values of M_{H} if one postulates the existence of a fourth generation of
leptons and quarks with isodoublet degenerate masses M_{L} and M_{Q} such that
60 GeV < M_{L} < 110 GeV and M_{Q} > 170 GeV.


title:
Matching Conditions for $b \to s \gamma$ and $b \to s gluon$ in
  Extensions of the Standard Model

abstract:
  We evaluate matching conditions for the Wilson coefficients of operators
mediating the $b \to s \gamma$ and $b \to s gluon$ transitions in a large class
of extensions of the Standard Model. The calculation is performed at the
leading order in flavor-changing couplings and includes two-loop QCD
corrections. These corrections can be numerically important when approximate
cancellations occur among the new physics contributions and/or the SM one.


title: On present status of R-parity violating supersymmetry

abstract: The paper has been withdrawn by the authors for modification.


title: TeV Neutrinos in a dense medium

abstract:
  The dispersion relation of energetic (few TeV) neutrinos traversing a medium
is studied. We use the real time formalism of thermal field theory and we
include the effects from the propagator of the W gauge boson. We consider then
the MSW oscillations for cosmic neutrinos traversing the Earth, adopting for
the neutrino parameters values suggested by the LSND results. It is found that
the $\nu_\mu$ flux, for neutrinos passing through the center of the Earth, will
appear reduced by 15% for energies around 10 TeV.


title: QCD Corrections to Radiative Upsilon Decays

abstract:
  We have calculated the next-to-leading order perturbative QCD corrections to
the photon energy spectrum in radiative Upsilon decays. The higher-order
corrections significantly modify the shape of the spectrum, in particular at
large photon energies, and thereby reduce the discrepancy between experimental
data and previous leading-order predictions. The next-to-leading order
calculation of the photon energy spectrum allows a more reliable determination
of the strong coupling constant from radiative Upsilon decays by restricting
the analysis to the region of the energy spectrum that can be described by NLO
perturbation theory.


title: Impact of bosonic decays on the search for stau_2 and tau-sneutrino

abstract:
  We perform a detailed study of the decays of the heavier tau slepton (stau_2)
and tau-sneutrino (snu_tau) in the Minimal Supersymmetric Standard Model
(MSSM). We show that the decays into Higgs or gauge bosons, i.e. stau_2 ->
stau_1 + (h^0, H^0, A^0 or Z^0), stau_2 -> snu_tau + (H^- or W^-), and snu_tau
-> stau_1 + (H^+ or W^+), can be very important due to the sizable tau Yukawa
coupling and large mixing parameters of stau. Compared to the decays into
fermions, such as stau_2 -> tau + neutralino_i and stau_2 -> nu_tau +
chargino_j^-, these bosonic decay modes can have significantly different decay
distributions. This could have an important influence on the search for stau_2
and snu_tau and the determination of the MSSM parameters at future colliders.


title:
In-medium parton energy losses and characteristics of hadronic jets in
  ultra-relativistic nuclear collisions

abstract:
  The angular structure of collisional and radiative energy losses of a hard
parton jet propagating through the quark-gluon plasma is analyzed. The
possibility to observe the energy losses of quark- and gluon-initiated jets in
dense QCD-matter (jet quenching) measuring the characteristics of real hadronic
jets in ultra-relativistic collisions of nuclei is investigated. In particular,
using calorimetric studies of jet + jet, gamma + jet and Z + jet channels is
discussed.


title:
Polarized photoproduction of large-p_T hadron pairs as a probe of the
  polarized gluon distribution

abstract:
  Production of large-p_T hadron pairs by polarized photon on a longitudinally
polarized proton towards probing the polarized gluon distribution is studied.
Resolved photon contributions and the effect of changing the scales are taken
into account, and predictions are presented. A very recent experimental result
at c.m. energy 7.18 GeV is compared to our predictions extented down to this
energy. A proper combination of cross sections is also considered.


title: Vector potential versus colour charge density in low-x evolution

abstract:
  We reconsider the evolution equations for multigluon correlators derived in
hep-ph/9709432. We show how to derive these equations directly in terms of
vector potentials (or colour field strength) avoiding the introduction of the
concept of colour charge density in the intermediate steps. The two step
procedure of deriving the evolution of the charge density correlators followed
by the solution of classical equations for the vector potentials is shown to be
consistent with direct derivation of evolution for vector potentials. In the
process we correct some computational errors of hep-ph/9709432 and present the
corrected evolution equations which have a somewhat simpler appearance.


title: Strong and Radiative Decays of Heavy Flavored Baryons

abstract:
  We analyze strong one-pion and radiative one-photon decays of heavy flavored
baryons within a relativistic three-quark model. Employing the same parameters
as were used for the description of the semileptonic decays of heavy baryons,
we calculate the couplings of one-pion and one-photon transitions of both
ground and excited heavy baryon states. We predict the decay rates for all
relevant decay modes and compare them with experimental data when available and
with the results of other model calculations.


title: Signals of Supersymmetric Lepton Flavor Violation at the LHC

abstract:
  In a generic supersymmetric extension of the Standard Model, there will be
lepton flavor violation at a neutral gaugino vertex due to misalignment between
the lepton Yukawa couplings and the slepton soft masses. Sleptons produced at
the LHC through the cascade decays of squarks and gluinos can give a sizable
number of events with 4 leptons. This channel could give a clean signature of
supersymmetric lepton flavor violation under conditions which are identified.


title:
Baryon Number Penetrability as a Measure of Isothermal Baryon Number
  Fluctuations in the Early Universe

abstract:
  We have examined the efficiency of baryon-number transport mechanism across
the phase boundary in a cosmological quark-hadron phase transition through the
proper estimate of baryon-number penetrability $<\Sigma_h>$. For this purpose
we have derived first the double-pair creation probability $P_b$ in terms of
single-pair creation probabilty per unit time and unit volume $\kappa_m$ and
then obtained an analytical expression for $<\Sigma_h >$. Our calculation is
free from the uncertainty of the value of double-pair creation probability per
unit time and unit volume $\kappa_b$ which was used as a free parameter in
earlier calculations. Finally the variations of double-pair creation
probability $P_b$ as well as $<\Sigma_h>$ with temperature are shown and
compared with other known results.


title:
Comment on Chernavskaya's Paper ``Double Phase Transition Model and the
  Problem of Entropy and Baryon Number Conservation" hep-ph/9701265

abstract: We comment on the paper hep-ph/9701265.


title:
gamma gamma -> gamma gamma as a Test of Weak Scale Quantum Gravity at
  the NLC

abstract:
  Recently, it has been proposed that the fundamental scale of quantum gravity
can be close to the weak scale if there are large extra dimensions. This
proposal has important phenomenological implications for processes at the TeV
scale. We study the process gamma gamma -> gamma gamma, assuming an ultraviolet
cutoff M_S \sim 1 TeV for the effective gravity theory. We find that, at center
of mass energies \sqrt(s) \sim 1 TeV, the contribution of gravitationally
mediated scattering to the cross section is comparable to that coming from the
one-loop Feynman diagrams of the Standard Model. We thus conclude that the
effects of weak scale quantum gravity can be studied at the Next Linear
Collider (NLC), in the photon collider mode. Our results suggest that, for
typical proposed NLC energies and luminosities, the range 1 TeV \lsim M_S \lsim
10 TeV can be probed.


title: Dynamical Inflation and Vacuum Selection

abstract:
  We consider an inflationary scenario where the energy scale of inflation
stems from gauge theory dynamics. We point out its generic implications on
vacuum selection of our universe, in particular, on determination of spacetime
symmetries including its dimensions.


title: CP Violation and Prospects at B Factories and Hadron Colliders

abstract:
  We review the information on the CKM matrix elements, unitarity triangle and
CP-violating phases $\alpha, \beta$ and $\gamma$ in the standard model which
will be measured in the forthcoming experiments at B factories, HERA-B and
hadron colliders. We also discuss two-body non-leptonic decays $B \to h_1 h_2$,
with $h_i$ being light mesons, which are interesting from the point of view of
CP violation and measurements of these phases. Partial rate CP asymmetries are
presented in a number of decay modes using factorization for the matrix
elements of the operators in the effective weak Hamiltonian. Estimates of the
branching ratios in this framework are compared with existing data on $B \to
K\pi,\eta' K, K^{*}\pi,\rho\pi$ decays from the CLEO collaboration.


title: Leptogenesis in Supersymmetric Hybrid Inflation

abstract:
  The nonsupersymmetric as well as the supersymmetric hybrid inflationary model
is reviewed. The scenario of baryogenesis via a primordial leptogenesis is
discussed and the role of the nonperturbative electroweak sphaleron effects is
analyzed. A supersymmetric model based on a left-right symmetric gauge group,
which `naturally' leads to hybrid inflation, is presented. The mu problem is
solved, in this model, and the baryon asymmetry of the universe is produced
through leptogenesis. For masses of nu_mu, nu_tau from the small angle MSW
resolution of the solar neutrino problem and SuperKamiokande, maximal
nu_mu-nu_tau mixing can be achieved. The required values of the relevant
parameters are, however, quite small.


title:
Spontaneous Supersymmetric Generation of an Indeterminate Mass Scale and
  a Possible Light Sterile Neutrino

abstract:
  If a global continuous symmetry of a supersymmetric field theory is
spontaneously broken while preserving the supersymmetry, the resulting theory
has a massless superfield. One of its two bosonic degrees of freedom is the
familiar phase rotation of the usual massless Nambu-Goldstone boson, but the
other is a scale transformation. An indeterminate mass scale is thus generated.
In the fermion sector, a seesaw texture appears which may be suitable for a
possible light sterile neutrino. This feature persists even after the gauging
of the continuous symmetry or the breaking of the supersymmetry to resolve the
aforementioned mass-scale ambiguity.


title: Vector-meson magnetic dipole moment effects in radiative tau decays

abstract:
  We study the possibility that the magnetic dipole moment of light charged
vector mesons could be measured from their effects in \tau^- -->
V^-\nu_{\tau}\gamma decays. We conclude that the energy spectrum and angular
distribution of photons emitted at small angles with respect to vector mesons
is sensitive the effects of the magnetic dipole moment. Model-dependent
contributions and photon radiation off other electromagnetic multipoles are
small in this region. We also compute the effects of the magnetic dipole moment
on the integrated rates and photon energy spectrum of these $\tau$ lepton
decays.


title: High-momentum asymptotics from the Fock-Feynman- Schwinger path integral

abstract:
  The asymptotics of n-point Green's function at large external momenta is
obtained in the exponentiated form using the Fock-Feynman-Schwinger
representation for propagators in the external field. The method is applied to
gauge theories such as QCD and QED, and the Sudakov form-factor is calculated
as an example in QED and meson form-factor in QCD. Nonperturbative
contributions can be conveniently included, as it is demonstrated in the
example of the confinement correction to the form-factor.


title: Moduli Forces in String Models with Large Internal Dimensions

abstract:
  We estimate the strength and range of forces mediated by string moduli in
type I string models with two (or more) large internal dimensions. We find that
forces mediated by twisted moduli which live on the brane world--volume can
mediate forces which are orders of magnitude stronger than gravity with a range
up to a milimeter. If they exist, these forces can be easily observed in
present experiments. On the other hand, forces mediated by the dilaton and
untwisted moduli are about a hundred times stronger than gravity and may be
observed depending on their range.


title: On fermion mass hierarchy with extra dimensions

abstract:
  Recently various phenomenological implications of the existence of extra
space-time dimensions have been investigated. In this letter, we construct a
model with realistic fermion mass hierarchy with (large) extra dimensions
beyond the usual four dimensions. In this model, it is assumed that some matter
fields live in the bulk and the others are confined on our four dimensional
wall. It can naturally reproduce the quark and lepton mass hierarchy and mixing
angles without any symmetry arguments. We also discuss some possibilities of
obtaining suitable neutrino masses and mixings for the solar and atmospheric
neutrino problems.


title:
Operator Product Expansion for Exclusive Decays: B^+ ->Ds^+ e+e- and B^+
  -> Ds^{*+} e+e-

abstract:
  The decays $B^+\to D_{s,d}^+e^+e^-$ and $B^+\to D_{s,d}^{*+}e^+e^-$ proceed
through a weak and an electromagnetic interaction. This is a typical ``long
distance'' process, usually difficult to compute systematically. We propose
that over a large fraction of phase space a combination of an operator product
and heavy quark expansions effectively turns this process into one in which the
weak and electromagnetic interactions occur through a local operator. Moreover,
we use heavy quark spin symmetry to relate all the local operators that appear
in leading order of the operator expansion to two basic ones. We use this
operator expansion to estimate the decay rates for $B^+\to
D_{s,d}^{(*)+}e^+e^-$.


title: Probing anomalous right--handed current in Z b bbar vertex

abstract:
  Motivated by $-2 \sigma$ deviation from the Standard Model prediction for the
forward--backward asymmetry of $Z \to b \bar{b}$ decay in the LEP data, we
explore the anomalous couplings of $Z b \bar{b}$ vertex through the electroweak
precision test extended by including $A_{FB}^b$. We introduce a new variable
$\epsilon'_b$ to measure the anomalous right-handed coupling in $Z b \bar{b}$
vertex. Implications of our analysis on the nonuniversal contact interactions
are studied and the left-right model is also considered as a possible origin of
the anomalous right-handed couplings.


title:
Enhancement of singly and multiply strangeness in p-Pb and Pb-Pb
  collisions at 158A GeV/c

abstract:
  The idea that the reduction of the strange quark suppression in string
fragmentation leads to the enhancement of strange particle yield in
nucleus-nucleus collisions is applied to study the singly and multiply strange
particle production in p-Pb and Pb-Pb collisions at 158A GeV/c. In this
mechanism the strange quark suppression factor is related to the effective
string tension, which increases in turn with the increase of the energy, of the
centrality and of the mass of colliding system. The WA97 observation that the
strange particle enhancement increases with the increasing of centrality and of
strange quark content in multiply strange particles in Pb-Pb collisions with
respect to p-Pb collisions was accounted reasonably.


title: Neutrino Physics and the Mirror World

abstract:
  Improper Lorentz Transformations can be retained as exact symmetries of
Nature if the particle content and gauge group of the Standard Model are
doubled. The resulting ``Exact Parity Model (EPM)'' sees each ordinary particle
paired with a mirror analogue. If neutrinos have mass and if they mix, then the
EPM predicts that each ordinary neutrino will be maximally mixed with its
mirror neutrino partner. This provides a very simple explanation for the very
large mixing angle observed for atmospheric muon neutrinos by SuperKamiokande
and other experiments. Maximal mixing for electron neutrinos is also well
motivated by the solar neutrino problem. If small interfamily mixing is
switched on, then the LSND anomaly can also be accomodated by the EPM. The EPM
thus provides a unified, simple and to some extent predictive framework for
explaining all of the anomalous neutrino data. This talk will briefly review
the EPM or mirror neutrino scenario.


title: Superheavy Dark Matter and Thermal Inflation

abstract:
  The thermal inflation is the most plausible mechanism that solves the
cosmological moduli problem naturally. We discuss relic abundance of superheavy
particle $X$ in the presence of the thermal inflation assuming that its
lifetime is longer than the age of the universe, and show that the long-lived
particle $X$ of mass $10^{12}$--$10^{14}$ GeV may form a part of the dark
matter in the present universe in a wide region of parameter space of the
thermal inflation model. The superheavy dark matter of mass $\sim 10^{13}$ GeV
may be interesting in particular, since its decay may account for the observed
ultra high-energy cosmic rays if the lifetime of the $X$ particle is
sufficiently long.


title:
The theoretical predictions for the study of the $a_0(980)$ and
  $f_0(980)$ mesons in the $\phi$ radiative decays

abstract:
  The potentialities of the production of the $a_0(980)$ and $f_0(980)$ mesons
in the $\phi$ radiative decays are considered.


title: A General Approach To Photon Radiation Off Fermions

abstract:
  Soft or collinear photon emission potentially poses numerical problems in the
phase-space integration of radiative processes. In this paper, a general
subtraction formalism is presented that removes such singularities from the
integrand of the numerical integration and adds back the analytically
integrated contributions that have been subtracted. The method is a
generalization of the dipole formalism of Catani and Seymour, which was
formulated for NLO QCD processes with massless unpolarized particles. The
presented formalism allows for arbitrary mass and helicity configurations in
processes with charged fermions and any other neutral particles. Particular
attention is paid to the limit of small fermion masses, in which collinear
singularities cause potentially large corrections. The actual application and
the efficiency of the formalism are demonstrated by the discussion of photonic
corrections to the processes \gamma \gamma --> t \bar t (\gamma), e^- \gamma
--> e^- \gamma (\gamma), and \mu^+ \mu^- --> \nu_e \bar\nu_e (\gamma).


title:
On the Measurement of D-meson Yield in Nucleus-Nucleus Collisions at the
  CERN SPS

abstract:
  We argue that the measurement of open charm gives a unique opportunity to
test the validity of pQCD-based and statistical models of nucleus-nucleus
collisions at high energies. We show that various approaches used to estimate
D-meson multiplicity in central Pb+Pb collisions at 158 A GeV give predictions
which differ by more than a factor of 100. Finally we demonstrate that decisive
experimental results concerning the open charm yield in A+A collisions can be
obtained using data of the NA49 experiment at the CERN SPS.


title: Generalized polarizabilities of the pion in chiral perturbation theory

abstract:
  We present a calculation of the virtual Compton scattering amplitude for
$\gamma^\ast+\pi\to \gamma+\pi$ in the framework of chiral perturbation theory
at ${\cal O}(p^4)$. We explicitly derive expressions for generalized
electromagnetic polarizabilities and discuss alternative definitions of these
quantities.


title: Atmospheric neutrinos: phenomenological summary and outlook

abstract:
  The predictions of the atmospheric nu event rates are affected by significant
uncertainties, however the evidence for the `disappearance' of nu_mu's and
nubar_mu's obtained by SK (and other underground detectors) is robust and
cannot be accounted in the framework of the minimum standard model without
assuming very large ad hoc experimental systematic effects. The existence of
`new physics' beyond the standard model is therefore close to be established;
neutrino oscillations provide a very good fit to all data. The theoretical
uncertainties do have an important role in the detailed interpretation of the
data, and in the estimate of oscillation parameters.


title: Phenomenology of Non-Standard Embedding and Five-branes in M-Theory

abstract:
  We study the phenomenology of the strong-coupling limit of $E_8\times E_8$
heterotic string obtained from M-theory, using a Calabi-Yau compactification.
After summarizing the standard embedding results, we concentrate on
non-standard embedding vacua as well as vacua where non-perturbative objects as
five-branes are present. We analyze in detail the different scales of the
theory, eleven-dimensional Planck mass, compactification scale, orbifold scale,
and how they are related taking into account higher order corrections. To
obtain the phenomenologically favored GUT scale is easier than in standard
embedding vacua. To lower this scale to intermediate ($\approx 10^{11}$ GeV) or
1 TeV values or to obtain the radius of the orbifold as large as a millimetre
is possible. However, we point out that these special limits are unnatural.
Finally, we perform a systematic analysis of the soft supersymmetry-breaking
terms. We point out that scalar masses larger than gaugino masses can easily be
obtained unlike the standard embedding case and the weakly-coupled heterotic
string.


title: Muon g-2 and New Physics

abstract:
  Here we invoke the current and future perspective on muon $g-2$ measurement
when asking what the muon $g-2$ could tell about the underlying structure
concerning with the hierarchy problem. Here we take up two such models, the
presence of which turns out to alter the standard model prediction for muon
$g-2$ significantly: one is TeV scale gravity scenario, the other
supersymmetric model, in the latter case of which the precision measurement up
to $Z$ boson mass is taken into account as an explicit constraint.


title: Finite Higher-Dimensional Unified Field Theory and TeV Physics

abstract:
  A unified field theory based on the compactification of a higher
D-dimensional Einstein-Yang-Mills-Higgs action is developed. The extra D-4
dimensions form a compact internal space with scale size R. An anomaly-free
unified chiral model of quarks and leptons, described by SO(18) in twelve
dimensions, breaks down to $SO(10)\times SO(8)\to SO(10)$ with a non-trivial
topological structure and three chiral families in four dimensions. A quantum
field theory formalism in D-dimensions leads to a self-consistent, finite
quantum gravity, Yang-Mills and Higgs theory, which is unitary and gauge
invariant to all orders of perturbation theory. The gauge hierarchy problem is
solved due to the exponential damping of the Higgs self-energy loop graph for
energies greater than $\sim 1$ TeV, and because of the reduction of quantum
gravity to a scale of several TeV. The compactification scale is $M_c\geq 1$
TeV, leading to Kaluza-Klein excitations and experimental signatures at a scale
of several TeV. Various scenarios for evading fast proton decay are discussed.


title: Charge and critical density of strange quark matter

abstract:
  The electric charge of strange quark matter is of vital importance to
experiments. A recent investigation shows that strangelets are most likely
highly negatively charged, rather than slightly positively charged as
previously believed. Our present study indicates that negative charges can
indeed lower the critical density, and thus be favorable to the experimental
searches in heavy ion collisions. However, too much negative charges can make
it impossible to maintain flavor equilibrium.


title:
Supersymmetric CP violating Phases and the LSP relic density and
  detection rates

abstract:
  For varying values of $\tan\beta$, we study the effect of CP violating phases
from the soft supersymmetry breaking terms in string-inspired models on the
relic abundance and detection rates of the lightest neutralino (LSP). We find
that the phases have no significant effect on the LSP relic abundance but can
have a substantial impact on the detection rates.


title: Perturbative QCD analysis of b-hadron lifetimes

abstract:
  We develop perturbative QCD factorization theorems for inclusive b-hadron
decays, in which radiative corrections characterized by the hadronic scale, the
b-hadron mass, and the W boson mass are absorbed into a heavy hadron
distribution function, a hard b quark decay amplitude, and a "harder" function,
respectively. Double logarithmic corrections associated with a light energetic
final-state quark, which appear at kinematic end points, are absorbed into a
jet function. Various large logarithms contained in the above functions are
summed to all orders, leading to the evolution factors among the three
characteristic scales. The heavy hadron distribution function is identical to
the one constructed in the framework of heavy quark effective theory. It is
shown that hadron kinematics must be employed in factorization theorems, and
that perturbative contributions, depending on hadron kinematics, distinguish
the lifetimes of the b-hadrons $B_d, B_s$ and $\Lambda_b$. Assuming the same
heavy-quark-effective-theory parametesr $\lambda_1$ for these hadrons, we
predict the lifetimes $\tau(B_d)=1.56$ ps, $\tau(B_s)=1.46$ ps and
$\tau(\Lambda_b)=1.22$ ps. We also predict the $B_u$ meson lifetime
$\tau(B_u)=1.62$ ps by varying the B meson distribution function slightly. All
the above results are consistent with experimental data.


title:
The gamma gamma to gamma Z process at high energies and the search for
  virtual SUSY effects

abstract:
  We study the helicity amplitudes and the observables of the process $\gamma
\gamma \to \gamma Z$ at high energy. As in the case of the $\gamma \gamma \to
\gamma\gamma$ process studied before, the relevant diagrams in the standard
model (SM) involve $W$, charged quark and lepton loops; while in SUSY we also
have contributions from chargino, and charged sfermion or Higgs loop diagrams.
Above 250 GeV, the dominant SM amplitudes are themselves dominated by the $W$
loop, and as for $\gamma \gamma \to \gamma \gamma$, they are helicity
conserving and almost purely imaginary. We discuss the complementary
information provided by $\gamma \gamma \to \gamma Z$ for the identification of
possible non standard effects. This process, together with $\gamma \gamma \to
\gamma \gamma$, should provide very useful information on the nature of
possible new physics particles, above the threshold of their direct production.


title:
Stringent constraint on the scalar-neutrino coupling constant from
  quintessential cosmology

abstract:
  An extremely light ($m_{\phi} \ll 10^{-33} {\rm eV}$), slowly-varying scalar
field $\phi $ (quintessence) with a potential energy density as large as 60% of
the critical density has been proposed as the origin of the accelerated
expansion of the Universe at present. The interaction of this smoothly
distributed component with another predominately smooth component, the cosmic
neutrino background, is studied. The slow-roll approximation for generic $\phi
$ potentials may then be used to obtain a limit on the scalar-neutrino coupling
constant, found to be many orders of magnitude more stringent than the limits
set by observations of neutrinos from SN 1987A. In addition, if quintessential
theory allows for a violation of the equivalence principle in the sector of
neutrinos, the current solar neutrino data can probe such a violation at the
10^{-10} level.


title:
Low-energy photon-photon fusion into three pions in Generalized Chiral
  Perturbation Theory

abstract:
  The processes $\gamma\gamma\to\pi^0\pi^0\pi^0$ and $\gamma\gamma\to \pi^+
\pi^- \pi^0$ are considered in Generalized Chiral Perturbation theory, in view
of their potential sensitivity to the mechanism of spontaneous breaking of
chiral symmetry and to various counterterms. The amplitudes are computed up to
order ${\cal O}(p^6)$. The event production rates are estimated for the Daphne
$\phi$-Factory and for a future $\tau$-Charm Factory.


title: Neutrino - electron processes in a strong magnetic field and plasma

abstract:
  The total set of the neutrino - electron processes in a presence of both
components of an active medium, hot dense plasma and strong magnetic field, is
investigated for the first time. The contribution of the processes $\nu e^- \to
\nu e^-$, $\nu e^+ \to \nu e^+$, $\nu \to \nu e^- e^+$, $\nu e^- e^+ \to \nu$
is shown to dominate and not to depend on the chemical potential of
electron-positron gas. Relatively simple expressions for the probability and
mean losses of the neutrino energy and momentum are obtained, which are
suitable for a quantitative analysis.


title:
Two photon decays of heavy vector mesons, $B^{*}\to B\gamma
  \gamma$,$D^{*}\to D\gamma \gamma$, and the possible determination of the
  $g_{B^{*}(D^{*})B(D)\pi}$ and $g_{{B^{*}}^0B^0\gamma}$ couplings

abstract:
  We study the novel decays $B^{*}\to B\gamma\gamma $ and $D^{*}\to D\gamma
\gamma $ using the framework of the Heavy Meson Chiral Lagrangian (HM$\chi$L)
to leading order in chiral perturbation theory. The branching ratios of these
decays are expressed in terms of the strong $g_{B^{*}(D^{*})B(D)\pi}$ and the
electromagnetic $g_{B^{*}(D^*)B(D)\gamma}$ couplings, thus providing a possible
tool for their determination. In the charm case, using the experimentally
determined ratios $({D^*}^{0,+}\to D\pi)/({D^*}^{0,+}\to D\gamma),$ we are able
to express the branching ratio as a function of the strong coupling only. We
thus find $1.6\times 10^{-6}<{\rm Br} ({D^{*}}^{0}\to
D^0\gamma\gamma)<3.3\times 10^{-5}$ for $0.25<g<1,$ where $g$ is the strong
coupling of HM$\chi$L. In the beauty sector, the ${\rm Br}({B^{*}}^{0} \to B^0
\gamma\gamma)$ which we estimate to be in the $10^{-7}-10^{-5}$ range is a
function of both $g_{B^{*}B\pi}$ and $g_{B^{*}B\gamma}.$ Its behaviour does not
afford an unambiguous determination of these couplings except for the region of
high $g$ values like $g>0.6.$ The expected two-photon differential
distributions are presented for both ${B^{*}}^{0} \to B^0 \gamma\gamma$ and
${D^{*}}^{0}\to D^0\gamma\gamma,$ for different values of the couplings
involved.


title: On Particle Multiplicities in Three-jet Events

abstract:
  A thorough verification of the distinct differences in the properties of
quark and gluon jets is considered as one of the most instructive tests of the
basic ideas of QCD. In the real life experiments such a comparison appears to
be quite a delicate task and various subtle issues require further theoretical
efforts. In this paper we discuss in detail the possibility to extract the
theoretically adequate information from the particle multiplicity patterns in
three-jet events in e+e- annihilation.


title: CP Violation and Weak Decays

abstract:
  I review some of the salient issues connected to CP-violation and weak
decays. In particular, I focus on recent and forthcoming tests of the CKM model
and discuss the accuracy one can expect to achieve in B-decays for the
parameters of this model.


title: Prompt atmospheric neutrinos and muons: NLO vs LO QCD predictions

abstract:
  We compare the leading and next-to-leading order QCD predictions for the flux
of atmospheric muons and neutrinos from decays of charmed particles. We find
that the full NLO lepton fluxes can be approximated to within 10% by the
Born--level fluxes multiplied by an overall factor of 2.2-2.4, which depends
slightly on the PDF. This supports the approach in Thunman, Ingelman, Gondolo
(1996). We also find that their very low lepton fluxes are due to the mild
slope they used for the gluon distribution function at small momentum
fractions, and that substantially larger lepton fluxes result when the slope of
the gluon distribution function at small momentum fractions is larger.


title:
The supersymmetric spectrum in SO(10) GUTs with gauge-mediated
  supersymmetry breaking

abstract:
  We investigate a large class of supersymmetric SO(10) grand unified theories
within the framework of gauge-mediated supersymmetry breaking. We start with
the most general messenger sector and imbedd the standard model gauge group
into either SU(2)_L X SU(2)_R X U(1)_{B-L} or SU(2)_L X U(1)_{I_{3R}} X
U(1)_{B-L}. We find that the conditions of the perturbativity of the gauge
couplings and unification at the GUT scale severely restrict the messenger
sector and lead to testable phenomenological predictions for the sparticle
masses. One of the most notable features of the class of supersymmetric SO(10)
grand unified theories introduced here is that among the many possible cases
there are only a few consistent models, all of which share an essentially
unique mass spectrum.


title: Chiral quarks, chiral limit, nonanalytic terms and baryon spectroscopy

abstract:
  It is shown that the principal pattern in baryon spectroscopy, which is
associated with the flavor-spin dependent hyperfine interaction, is due to the
spontaneous breaking of chiral symmetry in QCD and persists in the chiral
limit. All corrections, which are associated with a finite quark (Goldstone
boson) mass are suppressed by the factor $(\mu/\Lambda_\chi$)^2 and higher.


title: Theoretical Developments in Inclusive B Decays

abstract:
  Some recent theoretical work on inclusive B decays relevant for the model
independent determination of |V_{ub}| and |V_{cb}| is summarized. The
theoretical predictions and their reliability for several differential decay
distributions in B -> X_{c,u}e nu and B -> X_s gamma are reviewed. These can be
used to determine certain important HQET matrix elements. The upsilon expansion
and ways of testing it are discussed.


title: Glueball-quarkonia content and decay of scalar-isoscalar mesons

abstract:
  We investigate the hadronic two-body decay modes of the scalar-isoscalar
$f_0(1370)$, $f_0(1500)$ and $f_0(1710)$ states as resulting from the mixture
of the lowest lying scalar glueball with the isoscalar states of the ground
state $^3P_0$ $Q\bar Q$ nonet. In the decay analysis we take into account the
direct coupling of the quarkonia and glueball components of the $f_0$ states to
the quarkonia components of the two-meson final state with the decay dynamics
inspired by the strong coupling limit of QCD. We calculate partial decay widths
for the $f_0$ states in the proposed three-state mixing schemes and discuss
their compatibility with the observed decay features. Finally, we determine the
glueball-quarkonia content of the $f_0$ states from a detailed fit to
experimental decay data of $f_0(1500)$ and give predictions for the partial
decay widths of $f_0(1370)$ and $f_0(1710)$, providing thus a sensitive test of
the proposed mixing scheme.


title: Further Study On U(1) Gauge Invariance Restoration

abstract:
  To further investigate the applicability of the projection scheme for
eliminating the unphysical divergence $s/m_e^2$ due to U(1) gauge invariance
violation, we study the process $e^-+W^+\to e^-+\bar t+b$ which possesses
advantages of simplicity and clearness. Our study indicates that the projection
scheme can indeed eliminate the unphysical divergence $s/m_e^2$ caused by the
U(1) gauge invariance violation and the scheme can apply to very high energy
region.


title: Electron capture on ^{8}B nuclei and Superkamiokande results

abstract:
  The energy spectrum of recoil electrons from solar neutrino scattering, as
observed by Superkamiokande, is deformed with respect to that expected from SSM
calculations. We considered \nu-e scattering from neutrinos produced by the
electron-capture on ^{8}B nuclei, e^{-}+^{8}B --> ^{8}Be^{*}+\nu_{e}, as a
possible explanation of the spectral deformation. A flux \Phi_{eB}\simeq 10^{4}
cm^{-2} s^{-1} could account for Superkamiokande solar neutrino data. However
this explanation is untenable, since the theoretical prediction,
\Phi_{eB}=(1.3+-0.2) cm^{-2} s^{-1}, is smaller by four orders of magnitude.


title: The QCD pomeron in e+e- collisions

abstract:
  The contribution of the QCD pomeron to the processes: e+e- to e+e- J/psi
J/psi and e+ e- to e+ e- hadrons (with tagged electrons) is discussed. We focus
on reactions which occur via photon-photon collisions, with virtual photons
coming from the Weizsaecker-Wiliams spectrum of the electrons. We stress the
importance of the non-leading corrections to the BFKL equation and take into
account dominant non-leading effects which come from the requirement that the
virtuality of the exchanged gluons along the gluon ladder is controlled by
their transverse momentum squared. The \gamma* \gamma* cross-sections are found
to increase with increasing \gamma* \gamma* CM energy W as (W^2)^{\lambda_P}
while the cross-section for \gamma\gamma to J/psi J/psi is found to increase as
(W^2)^{2\lambda_P}. The parameter \lambda_P is slowly varying with energy W and
takes the values lambda_P \sim 0.23 - 0.35 depending on the process. We also
analyze the contribution of the soft pomeron for the total \gamma* \gamma*
cross-section. We compare results of our calculations to the recent data from
LEP.


title:
A phenomenological outlook on three-flavor atmospheric neutrino
  oscillations

abstract:
  The recent observations of atmospheric nu events from the Super-Kamiokande
experiment are compatible with three-flavor neutrino oscillations, occurring
dominantly in the nu_mu<--->nu_tau channel and subdominantly in the
nu_mu<--->nu_e channel. We present an updated analysis of the three-flavor
mass-mixing parameters consistent with the present phenomenology, including the
latest 45 kTy data sample from Super-Kamiokande. A comparison with our previous
results, based on 33 kTy data, shows that the oscillation evidence is
strengthened, and that the neutrino mass-mixing parameters are constrained in
smaller ranges.


title: Transverse Momentum Dependence of Cumulative Pions

abstract:
  In the framework of the recently proposed QCD based parton model for the
cumulative phenomena in the interactions with nuclei the dependence of the
cumulative pion production rates on the transverse momentum is studied. The
mean value of the transverse momentum is found to grow with x in the cumulative
region. The obtained results are in agreement with the available experimental
data.


title: Theory and Tests of CPT and Lorentz Violation

abstract:
  A general Lorentz-violating extension of the standard model of particle
physics, allowing for both CPT-even and CPT-odd effects, is described. Some of
its theoretical aspects and experimental implications are summarized.


title:
Top Quark Pair Production close to Threshold: Top Mass, Width and
  Momentum Distribution

abstract:
  The complete NNLO QCD corrections to the total cross section $\sigma(e^+e^-
\to Z*,\gamma*\to t\bar t)$ in the kinematic region close to the top-antitop
threshold are calculated by solving the corresponding Schroedinger equations
exactly in momentum space in a consistent momentum cutoff regularization
scheme. The corrections coming from the same NNLO QCD effects to the top quark
three-momentum distribution $d\sigma/d |\vec k_t|$ are determined. We discuss
the origin of the large NNLO corrections to the peak position and the
normalization of the total cross section observed in previous works and propose
a new top mass definition, the 1S mass M_1S, which stabilizes the peak in the
total cross section. If the influence of beamstrahlung and initial state
radiation on the mass determination is small, a theoretical uncertainty on the
1S top mass measurement of 200 MeV from the total cross section at the linear
collider seems possible. We discuss how well the 1S mass can be related to the
$\bar{MS}$ mass. We propose a consistent way to implement the top quark width
at NNLO by including electroweak effects into the NRQCD matching coefficients,
which then can become complex.


title: Dark Matter and its Particle Candidates

abstract:
  In these lectures we first briefly review the main observational facts which
imply that most part of matter in the Universe is not visible and some recent
intriguing experimental data which would point to a significant contribution to
Omega due to a cosmological constant. We subsequently discuss some particle
candidates for dark matter, with particular emphasis for the neutralino. We
present the main properties of this particle, also in the light of the most
recent experimental results in direct search for relic particles; furthermore,
we discuss the perspectives for their indirect searches.


title:
CP Violation in the Semileptonic B_{l4} (B^\pm -> pi^+ \pi^- l^\pm \nu)
  Decays

abstract:
  Direct CP violations in $B_{l4}$ decays ($B^\pm \to \pi^+\pi^- l^\pm
{\nu}_l$) are investigated within the Standard Model (SM) and also in its
extensions. In the decay processes, we include various excited states as
intermediate states decaying to the final hadrons, $\pi^+ + \pi^-$. The CP
violation within the SM is induced by the interferences between intermediate
resonances with different quark flavors. As extensions of the SM, we consider
CP violations implemented through complex scalar-fermion couplings in the
multi-Higgs doublet model and the scalar-leptoquark models. We calculate the
CP-odd rate asymmetry and the optimal asymmetry. We find that the optimal
asymmetry can be measured at $1\sigma$ level with about $10^9$ $B$-meson pairs
in the SM case and $10^3$--$10^7$ pairs in the extended model case, for
maximally-allowed values of CP-odd parameters in each case.


title: The Pure Leptonic Decays of B_c Meson and Their Radiative Corrections

abstract:
  The radiative corrections to the pure leptonic decay $B_c \to \ell\nu_{\ell}$
up-to one-loop order is presented. How to cancel the infrared divergences
appearing in the loop calculations, and the radiative decay $B_c \to
\ell\nu_{\ell}\gamma$ is shown precisely. It is emphasized that the radiative
decay may be separated properly and may compare with measurements directly as
long as the theoretical `softness' of the photon corresponds to the
experimental resolutions. Furthermore with a kind of non-relativistic
constituent quark model, a kind of typical long distance contributions to the
radiative decays is estimated, and it is shown that the contributions are
negligible in comparison with the accuracy of one-loop corrections and the
expected experimental measurements.


title: Predictions for all processes e^+e^- -> 4 fermions + gamma

abstract:
  The complete matrix elements for e^+ e^- -> 4f and e^+ e^- -> 4f + gamma are
calculated in the Electroweak Standard Model for polarized massless fermions.
The matrix elements for all final states are reduced to a few compact generic
functions. Monte Carlo generators for e^+ e^- -> 4f and e^+ e^- -> 4f + gamma
are constructed. We compare different treatments of the finite widths of the
electroweak gauge bosons; in particular, we include a scheme with a complex
gauge-boson mass that obeys all Ward identities. The detailed discussion of
numerical results comprises integrated cross sections as well as photon-energy
distributions for all different final states.


title: Lepton Parity in Supersymmetric Flavor Models

abstract:
  We investigate supersymmetric models where neither R-parity nor lepton number
nor baryon number is imposed. The full high energy theory has an exact
horizontal U(1) symmetry that is spontaneously broken. Quarks and Higgs fields
carry integer horizontal charges but leptons carry half integer charges.
Consequently, the effective low energy theory has two special features: a U(1)
symmetry that is explicitly broken by a small parameter, leading to selection
rules, and an exact residual Z_2 symmetry, that is lepton parity. As concerns
neutrino parameters, the Z_2 symmetry forbids contributions from R_p-violating
couplings and the U(1) symmetry induces the required hierarchy. As concerns
baryon number violation, the Z_2 symmetry forbids proton decay and the U(1)
symmetry provides sufficient suppression of double nucleon decay and of neutron
- antineutron oscillations.


title: CP, T Violation in Neutrino Oscillations

abstract:
  The manifestation of CP, T violation in the leptonic sector is studied for
flavour neutrino oscillations, both in vacuum and in matter. Different
conditions of short-base-line versus long-base-line experiments are discussed.


title: Comparing B -> X_u l nu_l to B -> X_s gamma

abstract:
  We suggest a method to determine V_ub / V_ts through a comparison of B -> X_u
l nu_l and B -> X_s gamma. The relevant quantity is the spectrum of the
light-cone component of the final state hadronic momentum, which in B -> X_s
gamma is the photon energy while in B -> X_u l nu_l this requires a measurement
of both hadronic energy and hadronic invariant mass. The non-perturbative
contributions at tree level to these distributions are identical and may be
cancelled by taking the ratio of the spectra. Radiative corrections to this
comparison are discussed to order alpha_s and are combined with the
non-perturbative contributions.


title:
The Das-Mathur-Okubo sum rule for the charged pion polarizability in a
  chiral model

abstract:
  The Das-Mathur-Okubo (DMO) sum rule for the polarizability of charged pions
is evaluated for the Nambu-Jona-Lasinio model Lagrangian in both its minimal
and extended forms. A comparison is made with the results obtained using the
same sum rule from chiral perturbation theory (CHPT), approximate QCD sum rule
calculations, explicit calculations on the lattice by Wilcox, and using the
semi-empirical Kapusta-Shuryak spectral densities. The $\chi$PT results from
Compton scattering are also given. We point to a delicate cancellation between
the intrinsic and recoil contributions to $\alpha_{\pi^\pm}$ in the DMO sum
rule approach that can lead to calculated polarizabilities of either sign.


title: Reconstruction of non-forward evolution kernels

abstract:
  We develop a framework for the reconstruction of the non-forward kernels
which govern the evolution of twist-two distribution amplitudes and off-forward
parton distributions beyond leading order. It is based on the knowledge of the
special conformal symmetry breaking part induced by the one-loop anomaly and
conformal terms generated by forward next-to-leading order splitting functions,
and thus avoids an explicit two-loop calculation. We demonstrate the formalism
by applying it to the chiral odd and flavour singlet parity odd sectors.


title: alpha^2 corrections to parapositronium decay

abstract:
  Two-loop QED corrections to the decay rate of parapositronium (p-Ps) into two
photons are presented. We find Gamma(p-Ps --> 2 photons) = 7989.64(2)/microsec.
The non-logarithmic O(alpha^2) corrections turn out to be small, contrary to
some earlier estimates. We speculate that the so-called ``orthopositronium
lifetime puzzle'' will not likely be solved by large QED corrections.


title: Recent results with heavy quarks and light lepton bound states

abstract:
  Recent results on second order quantum corrections to semileptonic decays of
b quarks and positronium spectroscopy are reviewed. Similarities between
calculations in these seemingly different problems are demonstrated. Technical
aspects of solving systems of recurrence relations, and application of
dimensional regularization to bound states are explained.


title:
Constraining the CKM Parameters using CP Violation in semi-leptonic B
  Decays

abstract:
  We discuss the usefulness of the CP violating semi-leptonic asymmetry a_{SL}
not only as a signal of new physics, but also as a tool in constraining the CKM
parameters. We show that this technique could yield useful results in the first
years of running at the B factories. We present the analysis graphically in
terms of M_{12}, the dispersive part of the B-Bbar mixing amplitude. This is
complementary to the usual unitarity triangle representation and often allows a
cleaner interpretation of the data.


title: Antideuterons as a Signature of Supersymmetric Dark Matter

abstract:
  Once the energy spectrum of the secondary component is well understood,
measurements of the antiproton cosmic-ray flux at the Earth will be a powerful
way to indirectly probe for the existence of supersymmetric relics in the
galactic halo. Unfortunately, it is still spoilt by considerable theoretical
uncertainties. As shown in this work, searches for low-energy antideuterons
appear in the mean time as a plausible alternative, worth being explored. Above
a few GeV/n, a dozen spallation antideuterons should be collected by the future
AMS experiment on board ISSA. For energies less than about 3 GeV/n, the
antideuteron spallation component becomes negligible and may be supplanted by a
potential supersymmetric signal. If a few low-energy antideuterons are
discovered, this should be seriously taken as a clue for the existence of
massive neutralinos in the Milky Way.