title: Parton Degrees of Freedom from the Path-Integral Formalism

abstract:
  We formulate the hadronic tensor $W_{\mu\nu}$ of deep inelastic scattering in
the path-integral formalism. It is shown that there are 3 gauge invariant and
topologically distinct contributions. Besides the valence contribution, there
are two sources for the sea -- one in the connected insertion and the other in
the disconnected insertion. The operator product expansion is carried out in
this formalism. The operator rescaling and mixing reveal that the connected sea
partons evolve the same way as the valence, i.e. their evolution is decoupled
from the disconnected sea and the gluon distribution functions. We explore the
phenomenological consequences of this classification in terms of the small x
behavior, Gottfried sum rule violation, and the flavor dependence. In
particular, we point out that in the nucleon $\bar{u}$ and $\bar{d}$ partons
have both the connected and disconnected sea contributions; whereas, $\bar{s}$
parton has only the disconnected sea contribution. This difference between
$\bar{u} + \bar{d}$ and $\bar{s}$, as far as we know, has not been taken into
account in the fitting of parton distribution functions to experiments.


title:
Is there window for "supersoft" Pomeron in $J/\psi$ photoproduction at
  low energy?

abstract:
  The low energy $J/\psi$ photoproduction cross-section has been studied on the
basis of the Pomeron model. To incorporate the discrepancy between experimental
data and the predictionns by the conventional models, i.e. the sum of the soft
Pomeron with intercept 1.08 and the hard Pomeron with intercept 1.418, a Regge
trajectory associated with a scalar meson (f,a) exchange which we call
"supersoft" Pomeron, is introduced additionally. To distinguish between the
conventional model and this new additional Pomeron, observations related to
other polarization observables in upcoming polarized experiments are discussed.


title: Option of three pseudo--Dirac neutrinos

abstract:
  As an alternative for popular see-saw mechanism, the option of three pseudo%
-Dirac neutrinos is discussed, where ${1/2}(m^{(L)} + m^{(R)}) \ll m^{(D)}$ for
their Majorana and Dirac masses. The actual neutrino mass matrix is assumed in
the form of tensor product $ M^{(\nu)} \otimes {(\{array} {cc} \lambda^{(L)} &
1 1 & \lambda^{(R)} \{array})}$, where $ M^{(\nu)}$ is a neutrino family mass
matrix ($ M^{(\nu) \dagger} = M^{(\nu)}$) and $\lambda^{(L,R)} \equiv
m^{(L,R)}/m^{(D)}$ with $ m^{(L)}$, $ m^{(R)}$ and $ m^{(D)} $ being taken as
universal for three neutrino families. It is shown that three neutrino effects
(deficits of solar $\nu_e $'s and atmospheric $ \nu_\mu $'s as well as the
possible LSND excess of $\nu_e $'s in accelerator $\nu_\mu $ beam) can be
nicely described by the corresponding neutrino oscillations, though the LSND
effect may, alternatively, be eliminated (by a parameter choice). Atmospheric
$\nu_\mu $'s oscillate dominantly into $\nu_\tau $'s, while solar $\nu_e $'s -
into (existing here automatically) Majorana sterile counterparts of $\nu_e $'s.
A phenomenological texture for neutrinos, compatible with the proposed
description, is briefly presented.


title:
Self-consistent hard-thermal-loop thermodynamics for the quark-gluon
  plasma

abstract:
  Self-consistent approximations allowing the calculation of the entropy and
the baryon density of a quark-gluon plasma are presented. These approximations
incorporate the essential physics of the hard thermal loops, involve only
ultraviolet-finite quantities, and are free from overcounting ambiguities.
While being nonperturbative in the strong coupling constant $g$, agreement with
ordinary perturbation theory is achieved up to and including order $g^3$. It is
shown how the pressure can be reconstructed from the entropy and the baryon
density taking into account the scale anomaly. The results obtained are in good
agreement with available lattice data down to temperatures of about twice the
critical temperature.


title: Hard diffractive electroproduction of two pions

abstract:
  We have calculated the leading order amplitude of hard diffractive
electroproduction of two pions in lepton nucleon scattering. At the leading
twist level a pion pair can be produced only in an isospin one or zero state.
We have shown that isoscalar states are produced dominantly for x_{Bj}>0.3 and
with an invariant mass of the two pions close to the threshold (S-wave) and in
the f_2 resonance region (D-wave). These isoscalar pion pairs are dominantly
produced by two collinear gluons.
  Comparing the production of charged and neutral pion pairs as a function of
x_{Bj} and m_pipi one can get information about the gluonic component of
two-pion distribution amplitudes.


title: Dynamics of the Inflationary Era

abstract:
  There is very strong circumstantial evidence that there was an inflationary
epoch very early in the history of the universe. In this lecture I will
describe how we might be able to piece together some understanding of the
dynamics during and immediately after the inflationary epoch.


title: String Breaking in Two-Dimensional QCD

abstract:
  I present results of a numerical calculation of the effects of light
quark-antiquark pairs on the linear heavy-quark potential in light-cone
quantized two-dimensional QCD. I extract the potential from the Q-Qbar
component of the ground-state wavefunction, and observe string breaking at the
heavy-light meson pair threshold. I briefly comment on the states responsible
for the breaking.


title: On the QCD Ground State at High Density

abstract:
  We investigate the possible ground states of QCD at asymptotic densities,
where the theory is expected to exhibit color superconductivity. We
characterize the color-flavor structure of possible diquark condensates, and
find those that are energy extrema by solving the weak-coupling Dyson-Schwinger
equations, including Landau damping and the Meissner effect. We show that, as
previously anticipated, in the two flavor case the vacuum breaks SU(3) color to
SU(2) and in the three flavor case the vacua with color-flavor locking (CFL)
have the lowest energy. We identify a number of relatively flat directions in
the potential along which the pattern of gauge symmetry breaking changes and
parity is violated. We discuss possible phenomenological consequences of our
results.


title:
Bi-maximal Neutrino Mixings And Proton Decay In SO(10) With Anomalous
  Flavor ${\cal U}(1)$

abstract:
  By supplementing supersymmetric SO(10) with an anomalous ${\cal U}(1)$ flavor
symmetry and additional `matter' superfields carrying suitable ${\cal U}(1)$
charges, we explain the charged fermion mass hierarchies, the magnitudes of the
CKM matrix elements, as well as the solar and atmospheric neutrino data. We
stress bi-maximal vacuum neutrino mixings, and indicate how the small or large
mixing angle MSW solution can be incorporated. The ${\cal U}(1)$ symmetry also
implies that $\tau_{p\to K\nu}[SO(10)]\sim (10-100)\cdot \tau_{p\to K\nu}[{\rm
minimal}~SU(5)]$.


title:
Indications for an Extra Neutral Gauge Boson in Electroweak Precision
  Data

abstract:
  A new analysis of the hadronic peak cross section at LEP 1 implies a small
amount of missing invisible width in Z decays, while the effective weak charge
in atomic parity violation has been determined recently to 0.6% accuracy,
indicating a significantly negative S parameter. As a consequence of these two
deviations, the data are described well if the presence of an additional Z'
boson, such as predicted in Grand Unified Theories, is assumed. Moreover, the
data are now rich enough to study an arbitrary extra Z' boson and to determine
its couplings in a model independent way. An excellent best fit to the data is
obtained in this case, suggesting the possibility of a family non-universal Z'
with properties similar to ones predicted in a class of superstring theories.


title: Relic Neutrinos, Z-Bursts, and Cosmic Rays above 10^{20} eV

abstract:
  The observation of cosmic--ray events above the Greisen-Kuzmin-Zatsepin (GZK)
cutoff of $\sim 5\times 10^{19}$ eV challenges orthodox modeling. We discuss a
possible solution which uses standard hot Big Bang cosmology and Standard Model
(SM) particle physics augmented only by $\lsim $ eV neutrino masses as
suggested by solar, atmospheric, and terrestrial neutrino detection. In this
scheme, cosmic ray neutrinos from distant, highest-energy sources annihilate
resonantly on the relic-neutrino background to produce Z-bosons. The
highly-boosted ($\gamma_Z\sim 10^{11}$) Z's instantly decay, producing
"Z-bursts" of highly-collimated jets of hadrons and photons. The burst content
includes, on average, twenty photons and two nucleons with super-GZK energies.
We show that the probability for each neutrino with energy within a fraction
$\Gamma_Z/M_Z$ of the resonant value $E_R=4(eV/m_\nu)\times 10^{21}$ eV to
annihilate within the halo of our galactic supercluster is likely within an
order of magnitude of 1%. Depending on the magnitude of the cosmic neutrino
flux above 10^{20} eV, this "local" rate for primary production may be high
enough to produce the cosmic ray events observed above the GZK cutoff. Several
tests of this Z-burst hypothesis for generating super-GZK events are presented,
including (i) a new cutoff energy at E_R; (ii) a large $\gamma/p$ ratio for
primaries near the upper end of the spectrum; (iii) directional pairing of
events, and pointing to their cosmic sources; and (iv) a neutrino flux above
the GZK cutoff energy which is possibly measurable directly in proposed $\gsim
10^{11}$ ton cosmic-ray detectors.


title:
Analytical approximations of the Lindhard equations describing radiation
  effects

abstract:
  Starting from the general Lindhard theory describing the partition of
particles energy in materials between ionisation and displacements, analytical
approximate solutions have been derived, for media containing one and more
atomic species, for particles identical and different to the medium ones.
Particular cases, and the limits of these equations at very high energies are
discussed.


title: Polarized Parton Densities and Processes

abstract:
  The main goals of `spin physics' are recalled, and some theoretical and
phenomenological aspects of longitudinally polarized deep inelastic scattering
and other hard processes are reviewed. The spin dependent parton densities of
protons and photons and polarized fragmentation functions are introduced, and
the relevant theoretical framework in next-to-leading order QCD is briefly
summarized. Technical complications typical for spin dependent calculations
beyond the leading order of QCD, like a consistent gamma_5 prescription, are
sketched, and some recent results for jet and heavy quark production are
discussed. Special emphasis is put on conceivable measurements at a future
polarized upgrade of the HERA collider which is currently under consideration.


title: Soft Limits of Multiparticle Observables and Parton Hadron Duality

abstract:
  We discuss observables in multiparticle production for three kinds of limits
of decreasing kinematical scales: 1. the transition jet \to hadron (limit
y_{cut}\to 0 of the resolution parameter y_{cut}); 2. single particle inclusive
distributions normalized at threshold \sqrt s\to 0 and 3. particle densities in
the limit of low momentum p,p_T\to 0. The observables show a smooth behaviour
in these limits and follow the perturbative QCD predictions, originally
designed for large scales, whereby a simple prescription is supplemented to
take into account mass effects. A corresponding physical picture is described.


title:
Pattern of Neutrino Oscillations in Supersymmetry with Bilinear R-parity
  Violation

abstract:
  Neutrino masses and their mixing are studied in detail in the framework of a
supersymmetric standard model with bilinear R-parity violation. In this
scenario, the mixing matrix among the neutrinos is in a restrictive form. We
find that only the small angle MSW solution is allowed for the solar neutrino
problem when the results of the CHOOZ experiment are combined with the mass
squared difference and mixing angle suggested by the atmospheric neutrino data.
Collider signals of this scenario are also discussed.


title:
Partial widths for the decays eta(1295) -> gamma gamma and eta(1440) ->
  gamma gamma

abstract:
  We discuss gamma gamma partial widths of pseudoscalar/isoscalar mesons eta(M)
in the mass region M = 1000-1500 MeV. The transition amplitudes eta(1295) ->
gamma gamma and eta(1440) -> gamma gamma are studied within an assumption that
the decaying mesons are the members of the first radial excitation nonet 2^1S_0
q\bar q. The calculations show that partial widths being of the order of 0.1
keV are dominantly due to the n\bar n meson component while the contribution of
the s\bar s component is small.


title: Transverse Momentum Structure of Diffractive DIS Models

abstract:
  The transverse momentum distribution of the diffractive final state provides
an interesting test of models of diffractive deep-inelastic scattering at HERA.
We present a comparison of several colour-singlet exchange models with thrust
transverse momentum data from a recent H1 analysis. We also study the effect of
constraints imposed on the kinematically-accessible phase space by data
selection cuts and find that, as a result of the pseudo-rapidity cut which is
used by H1 to select diffractive events, there is no dijet contribution at low
transverse momenta. We are able to fit the large transverse momentum part of
the data with a two-gluon dijet model. The results of this analysis are
compared with a previous study of large pseudo-rapidity gap structure function
data, and we discuss ways in which one might reconcile the results of the two
analyses. We conclude that a significant small-$\beta$ 3-jet contribution is
probably required to explain the data, and show that the combination of a
two-gluon dijet model and an exponentially-decaying thrust transverse momentum
distribution provides a good fit over the entire kinematic range of the thrust
data.


title:
Probing R-parity violation in the production of $t \bar{c}(c \bar{t})$
  on the lepton colliders

abstract:
  We studied the process $e^{+}e^{-} \to t\bar{c}+c\bar{t}$ in a R_{p}
violating supersymmetric model with effects from both B- and L-violating
interactions. The calculation shows that it is possible to either detect the
R_{p} violating signal at the Next Linear Collider or get more stringent
constraints on the heavy-flavor $\rlap/R_{p}$ couplings. A comparision with
results from $\gamma\gamma \to t\bar{c}+ c\bar{t}$ may allow to distinguish
between B- and L-violating interactions. For very clean background conditions
and R_{p} violation parameters close to present limits, a future detection of
B-violating interactions should be possible. The process of $\mu ^{+} \mu ^{-}
\to t \bar{c}+c\bar{t}$ is also considered.


title: Quark distributions in extended QCD sum rule approach

abstract:
  The improved calculation method of quark distributions in hadrons in the
framework of QCD sum rules is presented. The imaginary part of the virtual
photon scattering amplitude on some hadronic current is considered in the case,
when initial and final virtualities of the current $p^2_1$ and $p^2_2$ are
different, $p^2_1\not= p^2_2$. The double Borel transformation in $p^2_1,
p^2_2$ is applied to the sum rule, killing background non-diagonal transition
terms, which deteriorated the accuracy in the previous calculations. Valence
quark distributions in the pion were found in a good agreement with the data,
determined from the Drell-Yan process.


title:
Determining SUSY Parameters in Chargino Pair Production in e^+e^-
  Collisions

abstract:
  In most supersymmetric theories, charginos $\tilde{\chi}^\pm_{1,2}$ belong to
the class of the lightest supersymmetric particles and they are easy to observe
at e^+e^- colliders. By measuring the total cross sections and the left-right
asymmetries with polarized beams as well as the angular correlations of the
decay products of the charginos in $e^+e^-\to\tilde{\chi}^-_i\tilde{\chi}^+_j
[i,j=1,2]$, the chargino masses and the gaugino-higgsino mixing angles can be
determined. From these observables the relevant fundamental SUSY parameters can
be derived: M_2, $|\mu|$, $\cos\Phi_\mu$, and $\tan\beta=v_2/v_1$. The
solutions are unique.


title: Can the sneutrino be the lightest supersymmetric particle ?

abstract:
  Within the framework of the constrained Minimal Supersymmetric extension of
the Standard Model we show that recent LEP I limits on the invisible Z width
exclude the possibility that the lightest sparticle is the sneutrino.


title:
Resonant final-state interactions in D^0 -> \bar{K}^{0} {\eta},
  \bar{K}^{0} \eta' Decay

abstract:
  We have investimated the effect of the isospin 1/2, J^P = 0^+ resonant state
K^*_0(1950) on the decays D^0 ->\bar{K}^{0}\eta and D^0 ->\bar{K}^0 \eta' as a
function of the branching ratio sum r =Br(K^*_0(1950)->\bar{K}^0\eta)+
Br(K^*_0(1950)->\bar{K}^0 \eta' and coupling constants g_{K^*_0\bar{K}^0\eta},
g_{K^*_0\bar{K}^0\eta'}. We have used a factorized input for D^0 -> K^*_0(1950)
weak transition through a \pi K loop. We estimated both on- and off-shell
contributions from the loop. Our calculation shows that the off-shell effects
are significant. For $r\geq 30%$ a fit to the decay amplitude A(D^0 ->
\bar{K}^0 \eta') was possible, but the amplitude A(D^0 ->\bar{K}^0 \eta)
remained at its factorized value. For small values of r, $r\leq 18 %$, we were
able to fit A(D^0 -> \bar{K}^0 \eta), and despite the fact that A(D^0 ->
\bar{K}^0 \eta') could be raised by almost 100 % over its factorized value, it
still falls short of its experimental value. A simultaneous fit to both
amplitudes A(D^0 -> \bar{K}^0 \eta') and A(D^0 -> \bar{K}^0 \eta) was not
possible. We have also determined the strong phase of the resonant amplitudes
for both decays.
  PACS numbers:13.25.Ft, 13.25.-k, 14.40.Lb


title: Nucleon-Nucleon Parity Violation Experiments

abstract:
  Measurements of parity-violating longitudinal analyzing powers Az (normalized
asymmetries) in polarized proton-proton scattering and in polarized neutron
capture on the proton (n+p -> d+gamma) provide a unique window on the interplay
between the weak and strong interactions between and within hadrons. Several
new proton-proton parity violation experiments are presently either being
performed or are being prepared for execution in the near future: at TRIUMF at
221 MeV and 450 MeV and at COSY (Forschungszentrum Juelich) in the multi-GeV
range. A new measurement of the parity-violating gamma ray asymmetry with a
ten-fold improvement in the accuracy over previous measurements is being
developed at LANSCE. These experiments are intended to provide stringent
constraints on the set of six effective weak meson-nucleon coupling constants,
which characterize the weak interaction between hadrons in the energy domain
where meson exchange models provide an appropriate description. The 221 MeV pp
experiment is unique in that it selects a single transition amplitude, 3P2 -
1D2, and consequently constrains the weak meson-nucleon coupling constant
h_rho^(pp). The n+p -> d+gamma experiment is mainly sensitive to the weak
pion-nucleon coupling constant f_pi. Together with the existing pp parity
violation experimental results one may be able to delineate the various weak
meson-nucleon coupling constants. The anomalous result obtained at 6 GeV/c on a
water target requires that a new multi-GeV pp parity violation experiment be
performed.


title: Theory of Elastic Vector Meson Production

abstract:
  The elastic production of vector mesons at HERA is discussed from the
theoretical point of view. We briefly review different models, their successes
and shortcomings. Main emphasis is put on recent issues in perturbative QCD
calculations. Models including the vector meson wave function are compared with
an approach based on parton-hadron duality. We discuss several refinements of
these models in some detail, including the important role of off-diagonal
parton distributions.


title: Can Moduli Fields parametrize the Cosmological Constant?

abstract:
  We study the cosmological evolution of string/M moduli fields T. We use
T-duality to fix the potential and show that the superpotential W is a function
of the duality invariant function j(T) only. If W is given as a finite
polynomial of j then the moduli fields {\it do not} give an accelerating
universe, i.e. they {\it cannot} be used as quintessence. Furthermore, at T >>1
the potential is given by a double exponential potential V \simeq e^{-a
e^{\sqrt{2} T}} leading to a fast decaying behaviour at large times. For moduli
potentials with a finite v.e.v. of T the energy density redshift is model
dependent but if T has a finite mass, m < \infty, then the moduli energy
density redshifts faster or equal to matter. Only if the moduli mass is
infinite can the moduli energy density dominate the universe independently of
the initial conditions.


title: Inelastic diffraction and meson radii

abstract:
  It is shown that meson radii can be extracted from diffractive scattering
experiments of the type: $m+p\to m + X$, where p stands for the target proton,
and m for the incident charged meson $\pi^+$, $\pi^-$, $K^+$, or $K^-$. The
basis of the method used to perform this extraction is the QCD-based
SOC-picture for inelastic diffraction in high-energy hadron-hadron and
lepton-hadron collisions proposed in a recent Letter. The obtained results for
pion and kaon charge radii are compared with those determined in meson form
factor measurements.


title:
Renormalization and Running of Quark Mass and Field in the
  Regularization Invariant and MS-bar Schemes at Three and Four Loops

abstract:
  We derive explicit transformation formulae relating the renormalized quark
mass and field as defined in the MS-bar scheme with the corresponding
quantities defined in any other scheme. By analytically computing the
three-loop quark propagator in the high-energy limit (that is keeping only
massless terms and terms of first order in the quark mass) we find the NNNLO
conversion factors transforming the MS-bar quark mass and the renormalized
quark field to those defined in a ``Regularization Invariant'' (RI) scheme
which is more suitable for lattice QCD calculations. The NNNLO contribution in
the mass conversion factor turns out to be large and comparable to the previous
NNLO contribution at a scale of 2 GeV --- the typical normalization scale
employed in lattice simulations. Thus, in order to get a precise prediction for
the MS-bar masses of the light quarks from lattice calculations the latter
should use a somewhat higher scale of around, say, 3 GeV where the (apparent)
convergence of the perturbative series for the mass conversion factor is
better.
  We also compute two more terms in the high-energy expansion of the MS-bar
renormalized quark propagator. The result is then used to discuss the
uncertainty caused by the use of the high energy limit in determining the
MS-bar mass of the charmed quark. As a by-product of our calculations we
determine the four-loop anomalous dimensions of the quark mass and field in the
Regularization Invariant scheme. Finally, we discuss some physical reasons
lying behind the striking absence of zeta(4) in these computed anomalous
dimensions.


title: Review of Speculative "Disaster Scenarios" at RHIC

abstract:
  We discuss speculative disaster scenarios inspired by hypothetical new
fundamental processes that might occur in high energy relativistic heavy ion
collisions. We estimate the parameters relevant to black hole production; we
find that they are absurdly small. We show that other accelerator and
(especially) cosmic ray environments have already provided far more auspicious
opportunities for transition to a new vacuum state, so that existing
observations provide stringent bounds. We discuss in most detail the
possibility of producing a dangerous strangelet. We argue that four separate
requirements are necessary for this to occur: existence of large stable
strangelets, metastability of intermediate size strangelets, negative charge
for strangelets along the stability line, and production of intermediate size
strangelets in the heavy ion environment. We discuss both theoretical and
experimental reasons why each of these appears unlikely; in particular, we know
of no plausible suggestion for why the third or especially the fourth might be
true. Given minimal physical assumptions the continued existence of the Moon,
in the form we know it, despite billions of years of cosmic ray exposure,
provides powerful empirical evidence against the possibility of dangerous
strangelet production.


title: Hydrodynamic transport functions from quantum kinetic theory

abstract:
  Starting from the quantum kinetic field theory [E. Calzetta and B. L. Hu,
Phys. Rev. D37, 2878 (1988)] constructed from the closed-time-path (CTP),
two-particle-irreducible (2PI) effective action we show how to compute from
first principles the shear and bulk viscosity functions in the
hydrodynamic-thermodynamic regime. For a real scalar field with $\lambda \Phi
^{4}$ self-interaction we need to include 4 loop graphs in the equation of
motion. This work provides a microscopic field-theoretical basis to the
``effective kinetic theory'' proposed by Jeon and Yaffe [S. Jeon and L. G.
Yaffe, Phys. Rev. D53, 5799 (1996)], while our result for the bulk viscosity
reproduces their expression derived from linear response theory and the
imaginary-time formalism of thermal field theory. Though unavoidably involved
in calculations of this sort, we feel that the approach using fundamental
quantum kinetic field theory is conceptually clearer and methodically simpler
than the effective kinetic theory approach, as the success of the latter
requires clever rendition of diagrammatic resummations which is neither
straightforward nor failsafe. Moreover, the method based on the CTP-2PI
effective action illustrated here for a scalar field can be formulated entirely
in terms of functional integral quantization, which makes it an appealing
method for a first-principles calculation of transport functions of a thermal
non-abelian gauge theory, e.g., QCD quark-gluon plasma produced from heavy ion
collisions.


title:
Describing Analytically the Matter-Enhanced Two-Neutrino Transitions in
  a Medium

abstract:
  A general exact analytic expression for the probability of matter-enhanced
two-neutrino transitions in a medium (MSW, RSFP, generated by neutrino FCNC
interactions, etc.) is derived. The probability is expressed in terms of three
real functions of the parameters of the transitions: the ``jump'' probability
and two phases (angles). The results obtained can be utilized, in particular,
in the studies of the matter-enhanced transitions/conversions of solar and
supernova neutrinos. An interesting similarity between the Schroedinger
equation for the radial part of the non-relativistic wave function of the
hydrogen atom and the equation governing the MSW transitions of solar neutrinos
in the exponentially varying matter density in the Sun is also briefly
discussed.


title: Four-Neutrino Oscillations

abstract:
  It is shown that at least four massive neutrinos are needed in order to
accommodate the evidences in favor of neutrino oscillations found in solar and
atmospheric neutrino experiments and in the LSND experiment. Among all
four-neutrino schemes, only two, with a mass spectrum composed of two pairs of
neutrinos with close masses separated by the "LSND gap" of the order of 1 eV,
are compatible with the results of all neutrino oscillation experiments. In
these two schemes the probability of nu_e transitions into other states, the
probability of nu_mu->nu_e transitions and the size of CP violation effects in
nu_mu->nu_e transitions are suppressed in long-baseline experiments.


title:
Out of Equilibrium Thermal Field Theories - Finite Time after Switching
  on the Interaction - Wigner Transforms of Projected Functions

abstract:
  We study out of equilibrium thermal field theories with switching on the
interaction occurring at finite time using the Wigner transforms (in relative
space-time) of two-point functions.
  For two-point functions we define the concept of projected function: it is
zero if any of times refers to the time before switching on the interaction,
otherwise it depends only on the relative coordinates. This definition includes
bare propagators, one-loop self-energies, etc. For the infinite-average-time
limit of the Wigner transforms of projected functions we define the analyticity
assumptions: (1) The function of energy is analytic above (below) the real
axis. (2) The function goes to zero as the absolute value of energy approaches
infinity in the upper (lower) semiplane.
  Without use of the gradient expansion, we obtain the convolution product of
projected functions. We sum the Schwinger-Dyson series in closed form. In the
calculation of the Keldysh component (both, resummed and single self-energy
insertion approximation) contributions appear which are not the Wigner
transforms of projected functions, signaling the limitations of the method.
  In the Feynman diagrams there is no explicit energy conservation at vertices,
there is an overall energy-smearing factor taking care of the uncertainty
relations.
  The relation between the theories with the Keldysh time path and with the
finite time path enables one to rederive the results, such as the cancellation
of pinching, collinear, and infrared singularities, hard thermal loop
resummation, etc.


title: Resummation of double logarithms in electroweak high energy processes

abstract:
  At future linear $e^+e^-$ collider experiments in the TeV range, Sudakov
double logarithms originating from massive boson exchange can lead to
significant corrections to the cross sections of the observable processes.
These effects are important for the high precision objectives of the Next
Linear Collider. We use the infrared evolution equation, based on a gauge
invariant dispersive method, to obtain double logarithmic asymptotics of
scattering amplitudes and discuss how it can be applied, in the case of broken
gauge symmetry, to the Standard Model of electroweak processes. We discuss the
double logarithmic effects to both non-radiative processes and to processes
accompanied by soft gauge boson emission. In all cases the Sudakov double
logarithms are found to exponentiate. We also discuss double logarithmic
effects of a non-Sudakov type which appear in Regge-like processes.


title: Second Order QCD Corrections to the Top Decay Rate

abstract:
  We report on a recent calculation of the top decay rate up to order
\alpha_s^2. It is based on asymptotic expansions of the off-shell top
propagator, followed by a Pad\'e approximation in order to reach the physically
relevant point q^2=Mt^2.


title: Phenomenology of Neutrino Masses and Mixing

abstract:
  We discuss all possible schemes with four massive neutrinos inspired by the
existing experimental indications in favour of neutrino mixing, namely the
atmospheric, solar and LSND neutrino experiments. We argue that the scheme with
a neutrino mass hierarchy is not compatible with the experimental results,
likewise all other schemes with the masses of three neutrinos close together
and the fourth mass separated by a gap needed to incorporate the LSND neutrino
oscillation result. Only two schemes with two pairs of neutrinos with nearly
degenerate masses separated by this gap of the order of 1 eV are in agreement
with the results of all experiments, including those where no indications for
neutrino oscillations have been found. We also point out the possible effect of
big-bang nucleosynthesis on the 4-neutrino mixing matrix and its consequences
for neutrino oscillations. Finally, we study predictions for neutrino
oscillation experiments and $^3$H and $(\beta \beta)_{0\nu}$ decays, following
from the two favoured neutrino mass spectra and mixing schemes. These
predictions can be conceived as checks of the input used for arriving at the
two favoured schemes.


title: Resonant sneutrino production at Tevatron Run II

abstract:
  We consider the single chargino production at Tevatron $p \bar p \to \tilde
\nu_i \to \tilde \chi^{\pm}_1 l_i^{\mp}$ as induced by the resonant sneutrino
production via a dominant \RPV coupling of type $\l'_{ijk} L_i Q_j D_k^c$.
Within a supergravity model, we study the three leptons final state. The
comparison with the expected background demonstrate that this signature allows
to extend the sensitivity on the \susyq mass spectrum beyond the present LEP
limits and to probe the relevant \RPV coupling down to values one order of
magnitude smaller than the most stringent low energy indirect bounds. The
trilepton signal offers also the opportunity to reconstruct the neutralino mass
in a model independent way with good accuracy.


title:
Lambda_b and Lambda_c baryon decays at finite values of heavy quark
  masses

abstract:
  Semileptonic decays of Lambda_b and Lambda_c baryons are studied within the
Relativistic Three-Quark Model using finite heavy quark mass values. Employing
the same parameters as have been used previously for the description of
exclusive decays of heavy baryons in the heavy quark limit we calculate the six
form factors of the process and the corresponding decay rates. Our calculation
shows that the ``finite mass'' corrections are important in heavy-to-light
transitions and are not negligible in heavy-to-heavy transitions.


title: The resummed thrust distribution in DIS

abstract:
  We present preliminary results on the resummation of leading and
next-to-leading logarithms for the thrust distribution in deep inelastic
scattering. Our predictions, expanded to O(alpha_s^2), are compared to
corresponding results from the Monte Carlo programs DISASTER++ and DISENT.


title: Shear viscosity in $\phi^4$ theory from an extended ladder resummation

abstract:
  We study shear viscosity in weakly coupled hot $\phi^4$ theory using the CTP
formalism . We show that the viscosity can be obtained as the integral of a
three-point function. Non-perturbative corrections to the bare one-loop result
can be obtained by solving a decoupled Schwinger-Dyson type integral equation
for this vertex. This integral equation represents the resummation of an
infinite series of ladder diagrams which contribute to the leading order
result. It can be shown that this integral equation has exactly the same form
as the Boltzmann equation. We show that the integral equation for the viscosity
can be reexpressed by writing the vertex as a combination of polarization
tensors. An expression for this polarization tensor can be obtained by solving
another Schwinger-Dyson type integral equation. This procedure results in an
expression for the viscosity that represents a non-perturbative resummation of
contributions to the viscosity which includes certain non-ladder graphs, as
well as the usual ladders. We discuss the motivation for this resummation. We
show that these resummations can also be obtained by writing the viscosity as
an integral equation involving a single four-point function. Finally, we show
that when the viscosity is expressed in terms of a four-point function, it is
possible to further extend the set of graphs included in the resummation by
treating vertex and propagator corrections self-consistently. We discuss the
significance of such a self-consistent resummation and show that the integral
equation contains cancellations between vertex and propagator corrections.


title: Quark mass effects to \sigma(e^+e^- -> hadrons) at O(\alpha_s^3)

abstract:
  The calculation of the quartic mass terms at order \alpha_s^3 to the hadronic
R ratio is described. It is based on the operator product expansion for the
quark current correlator, combined with an application of the renormalization
group equation.


title: Extra-dimensional gravity and dijet production at gamma gamma colliders

abstract:
  In this note, we consider dijet production at gamma gamma colliders as a
probe of recently proposed, large extra-dimensional gravity models. The
exchange of virtual, spin-2 graviton towers (Kaluza-Klein excitations)
significantly modifies the cross section, as compared to the Standard Model
predictions. We find that, in order to maximize the value of the effective
scale that can be probed at a given center-of-mass energy, a very severe p_T
cut should be applied; in general, a p_T equal to approximately 46% of the e^+
e^- beam energy gives the highest reach. We find that we can probe the
effective mass scale from about 2.7 TeV to 11.1 TeV, depending on the
center-of-mass energy and assumptions about the model.


title: Dense QCD : Overhauser or BCS Pairing ?

abstract:
  We discuss the Overhauser effect (particle-hole pairing) versus the BCS
effect (particle-particle or hole-hole pairing) in QCD at large quark density.
In weak coupling and to leading logarithm accuracy, the pairing energies can be
estimated exactly. For a small number of colors, the BCS effect overtakes the
Overhauser effect, while for a large number of colors the opposite takes place,
in agreement with a recent renormalization group argument. In strong coupling
with large pairing energies, the Overhauser effect may be dominant for any
number of colors, suggesting that QCD may crystallize into an insulator at a
few times nuclear matter density, a situation reminiscent of dense Skyrmions.
The Overhauser effect is dominant in QCD in 1+1 dimensions, although
susceptible to quantum effects. It is sensitive to temperature in all
dimensions.


title: Fluctuations from dissipation in a hot non-Abelian plasma

abstract:
  We consider a transport equation of the Boltzmann-Langevin type for
non-Abelian plasmas close to equilibrium to derive the spectral functions of
the underlying microscopic fluctuations from the entropy. The correlator of the
stochastic source is obtained from the dissipative processes in the plasma.
This approach, based on classical transport theory, exploits the well-known
link between a linearized collision integral, the entropy and the spectral
functions. Applied to the ultra-soft modes of a hot non-Abelian (classical or
quantum) plasma, the resulting spectral functions agree with earlier findings
obtained from the microscopic theory. As a by-product, it follows that
B\"odeker's effective theory is consistent with the fluctuation-dissipation
theorem.


title: The Hot Dark Matter

abstract:
  There is a puzzling contradiction: direct observations favor a
low-mass-density universe ($0.2\le\Omega_m\le0.6$), but the only model which
fits universe structure over more than three orders of magnitude in distance
scale has a mix of hot (neutrino) and cold dark matter providing a critical
density universe. Models of an open universe (low $\Omega_m$) or one adding a
cosmological constant ($\Lambda$) to provide a critical energy density
($\Omega_m+ \Omega_\Lambda=1$) have probabilities of $<10^{-3}$. Two-neutrino
dark matter works better than having the needed $\sim5$ eV of neutrino mass in
one species of neutrino, and this is consistent with the only model which fits
all present indications for neutrino mass: $\nu_\mu\to\nu_\tau$ accounting for
the atmospheric anomaly (with $\nu_\mu$ and $\nu_\tau$ being the hot dark
matter), $\bar\nu_\mu\to\bar\nu_e$ being observed by LSND, and $\nu_e\to\nu_s$
explaining the solar $\nu_e$ deficit. The LSND/KARMEN results are consistent
with the needed mass of hot dark matter. Further support for this mass pattern
is provided by the need for the sterile neutrino, $\nu_s$, to make possible
heavy-element nucleosynthesis in supernovae. It is a fascinating question as to
whether the hot dark matter paradox will be resolved by better measurements or
by the introduction of new physics.


title: Helicity and partial wave amplitude analysis of D -> K^* \rho decay

abstract:
  We have carried out an analysis of helicity and partial-wave amplitudes for
the process D -> K^* \rho in the factorization approximation using several
models for the form factors. All the models, with the exception of one,
generate partial-wave amplitudes with the hierarchy $\mid S\mid >\mid P\mid
>\mid D\mid$. The one exception gives $\mid S \mid >\mid D \mid >\mid P \mid$.
Even though in most models the D-wave amplitude is an order of magnitude
smaller than the S-wave amplitude, its effect on the longitudinal polarization
could be as large as 30%. Due to a misidentification of the partial-wave
amplitudes in terms of the Lorentz structures in the relevant literature, we
cast doubt on the veracity of the listed data, particularly the partial-wave
branching ratios.
  (PACS numbers: 13.25.-k, 13.25.Ft)


title: Chiral Lagrangian treatment of pi eta scattering

abstract:
  We study pi eta scattering in a model which starts from the tree diagrams of
a non-linear chiral Lagrangian including appropriate resonances. Previously,
models of this type were applied to pi pi and pi K scattering and were seen to
require the existence of light scalar sigma(560) and kappa(900) mesons and to
be consistent with the f0(980). The present calculation extends this to include
the a0(980), thereby completing a possible nonet of light scalars, all ``seen''
in the same manner. We note that, at the initial level, the pi eta channel is
considerably cleaner than the pi pi and pi K channels for the study of light
scalars. This is because the large competing effects of vector meson exchange
and ``current-algebra'' contact terms are absent. The simplicity of this
channel enables us to demonstrate the closeness of our exactly crossing
symmetric amplitude to a related exactly unitary amplitude. The calculation is
also extended to higher energies in order to let us discuss the role played by
the a0(1450) resonance.


title: Evolution of a global string network in a matter dominated universe

abstract:
  We evolve the network of global strings in the matter-dominated universe by
means of numerical simulations. The existence of the scaling solution is
confirmed as in the radiation-dominated universe but the scaling parameter
$\xi$ takes a slightly smaller value, $\xi \simeq 0.6 \pm 0.1$, which is
defined as $\xi = \rho_{s} t^{2} / \mu$ with $\rho_{s}$ the energy density of
global strings and $\mu$ the string tension per unit length. The change of
$\xi$ from the radiation to the matter-dominated universe is consistent with
that obtained by Albrecht and Turok by use of the one-scale model. We also
study the loop distribution function and find that it can be well fitted with
that predicted by the one-scale model, where the number density $n_{l}(t)$ of
the loop with the length $l$ is given by $n_{l}(t) = \nu/[t^2 (l + \kappa
t)^2]$ with $\nu \sim 0.040$ and $\kappa \sim 0.48$. Thus, the evolution of the
global string network in the matter-dominated universe can be well described by
the one-scale model as in the radiation-dominated universe.


title: Dynamical screening in hot systems away from (chemical) equilibrium

abstract:
  Within the Closed Time Path Formalism of Thermal Field Theory we calculate
the hard photon emission rate as well as the collisional energy-loss rate for a
quark-gluon plasma away from chemical equilibrium. Mass singularities are shown
to be dynamically screened within HTL-resummed perturbation theory also away
from equilibrium. Additional (pinch) singularities are absent and well defined
results are obtained.


title: Electroweak phase transition: recent results

abstract:
  Recent results of four-dimensional (4d) lattice simulations on the finite
temperature electroweak phase transition (EWPT) are discussed. The phase
transition is of first order in the SU(2)-Higgs model below the end point Higgs
mass 66.5$\pm$1.4 GeV. For larger masses a rapid cross-over appears. This
result completely agrees with the results of the dimensional reduction
approach. Including the full Standard Model (SM) perturbatively the end point
is at 72.1$\pm$1.4 GeV. Combined with recent LEP Higgs mass lower bounds, this
excludes any EWPT in the SM. A one-loop calculation of the static potential
makes possible a precise comparison of the lattice and perturbative results.
Recent 4d lattice studies of the Minimal Supersymmetric SM (MSSM) are also
mentioned.


title: The Fractal Properties of the Source and BEC

abstract:
  Using simple space-time implementation of the random cascade model we
investigate numerically influence of the possible fractal structure of the
emitting source on Bose-Einstein correlations between identical particles. The
results are then discussed in terms of the non-extensive Tsallis statistics.


title:
Heavy Flavor Contributions to QCD Sum Rules and the Running Coupling
  Constant

abstract:
  We have calculated first and second order corrections to several sum rules
measured in deep inelastic lepton-hadron scattering. These corrections, which
are due to heavy flavors only, are compared with the existing perturbation
series which is computed for massless quarks up to third order in the strong
coupling constant \alpha_s. A study of the perturbation series reveals that the
large logarithms of the type ln^i Q^2/m^2 dominate the perturbation series at
much larger values than those given by the usual matching conditions imposed on
the \alpha_s(\mu). Therefore these matching conditions cannot be used to
extrapolate the running coupling constant from small \mu to very large scales
like \mu=M_Z. An alternative description of the running coupling constant in
the MOM-scheme is proposed.


title: Are Neutrinos Dirac or Majorana Particles?

abstract:
  In spite of the general belief that neutrinos are Majorana particles, their
character should be revealed experimentally. We begin by discussing why it is
so difficult in terrestrial experiments. If neutrinos are Majorana particles,
the first signal should come from neutrinoless double $\beta $ decay. Still the
search for such a decay of various nuclei is negative. We outline how the
present knowledge of neutrino masses and mixing matrix elements combined with
the bound from $(\beta \beta)_{0\nu}$ decay could help to determine their
nature.


title: Radiative Corrections to the Left-Right Model

abstract:
  The oblique part of the radiative corrections to the Left-Right model is
described. The leading non-logarithmic terms are explicitly written. It is
argued, on the basis of a comparison with the Standard Model, that one cannot
use the loop contributions of the latter to refine phenomenological analyses of
the Left-Right model, and by the same of any general extension.


title:
SO(10) \times SO(10) Universal Seesaw Model and its Intermediate Mass
  Scales

abstract:
  On the basis of the universal seesaw mass matrix model, which is a promising
model of the unified description of the quark and lepton mass matrices, the
behaviors of the gauge coupling constants and intermediate energy scales in the
SO(10)_L \times SO(10)_R model are investigated related to the neutrino mass
generation scenarios. The non-SUSY model cannot give favorable values of the
intermediate energy scales to explain the smallness of the neutrino masses,
while the SUSY model can give the plausible values if the number n_\phi of the
weak doublet Higgs scalars is n_\phi \geq 3.


title: Determination of the Strong Coupling Constant in Jet Production at HERA

abstract:
  Recent \alphas determinations from jet production at HERA are presented.
Three different observables lead to consistent alpha values. The result is
consistent with the world average and has an error of about 0.006. This is
quite a remarkable result, since it is only slightly less precise than the
world average.


title:
Strangeness Photoproduction from the Deuteron and Hyperon-Nucleon
  Interaction

abstract:
  Pronounced effects due to final state hyperon-nucleon interaction are
predicted in strangeness photoproduction reaction on the deuteron. Use is made
of the covariant reaction formalism and the P- matrix approach to the
hyperon-nucleon interaction.


title: Decoupling Dynamical Electroweak Symmetry Breaking

abstract:
  The modern precision accelerator data has essentially ruled out the most
obvious model of dynamical electroweak symmetry breaking, technicolour. The
idea is though well motivated and it is important to construct models
compatible with the precision data of this ilk to motivate experimental
searches. We describe the top-see-saw and flavour universal symmetry breaking
models that break electroweak symmetry dynamically yet have a decoupling limit
for all new physics. Limits on the scale of such new physics may be placed
using precision data and direct search results from the Tevatron.


title:
Evidence for Quark Gluon Plasma from Hadron Production in High Energy
  Nuclear Collisions

abstract:
  The experimental results on the pion, strangeness and J/psi production in
high energy nuclear collisions are discussed. The anomalous energy dependence
of pion and strangeness production is consistent with the hypothesis that a
transition to a deconfined phase takes place between the top AGS (15 AGeV) and
the SPS (200 AGeV) energies. The J/psi production systematics at the SPS can be
understood assuming that the J/psi mesons are created at hadronization
according to the available hadronic phase space. This new interpretation of the
J/psi data allows one to establish a coherent picture of high energy nuclear
collisions based on the statistical approaches of the collision early stage and
hadronization. Surprisingly, the statistical model of strong interactions is
successful even in the region reserved up to now for pQCD based models.


title: Matching in Nonrelativistic Effective Quantum Field Theories

abstract:
  Nonrelativstic effective field theories have shown to be a useful framework
to describe systems of weakly bound particles. This work focuses on the
matching procedure to the underlying relativistic theory. The concept of a
physical mass in the absence of explicit Lorentz symmetry and the matching
conditions for S-matrix elements and Green's functions are discussed in general
for scalar particles. The effective Lagrangians of the pure particle and
anti-particle sectors are constructed explicitely for a Yukawa-type interaction
of a heavy and a light scalar field. Using the proper matching, it is shown
that they reproduce the corresponding relativistic amplitudes in a systematic
expansion in inverse powers of the heavy mass.


title: Theories of Neutrino Masses and Mixings

abstract:
  Recent developments in our understanding of neutrino masses and their
implications for physics beyond the standard model are reviewed.


title: Light Higgs production at the Compton Collider

abstract:
  We have studied the production of a light Higgs boson with a mass of 120 GeV
in photon-photon collisions at a Compton collider. The event generator for the
backgrounds to a Higgs signal due to bbbar and ccbar heavy quark pair
production in polarized gamma-gamma collisions is based on a complete
next-to-leading order (NLO) perturbative QCD calculation. For J_z=0 the large
double-logarithmic corrections up to four loops are also included. It is shown
that the two-photon width of the Higgs boson can be measured with high
statistical accuracy of about 2 % for integrated gamma-gamma luminosity in the
hard part of the spectrum of 40 fb**-1. As a result the total Higgs boson width
can be calculated in a model independent way to an accuracy of about 14 %


title:
Nonperturbative calculation of the shear viscosity in hot phi**4 theory
  in real time

abstract:
  Starting from the Kubo formula we calculate the shear viscosity in hot phi**4
theory nonperturbatively by resumming ladders with a real-time version of the
Bethe-Salpeter equation at finite temperature. In the weak coupling limit, the
generalized Fluctuation-Dissipation Theorem is shown to decouple the
Bethe-Salpeter equations for the different real-time components of the 4-point
function. The resulting scalar integral equation is identical with the one
obtained by Jeon using diagrammatic ``cutting rules'' in the Imaginary Time
Formalism.


title: Neutral kaons as instrument for studying heavier flavors

abstract:
  Strangeness oscillations in decays of neutral kaons are suggested to be used
as an analyzer to investigate detailed properties of heavy flavor hadrons and
their decays. Here we briefly explain why, where, and to what problems this
approach may be applied.


title: Hyperon Physics-a Personal Overview

abstract:
  A range of issues in the field of hyperon physics is presented, together with
an assessment of where important challenges remain.


title: On the reaction $ep \to ep \gamma$

abstract:
  We have studied the reaction $ep \to ep \gamma$ in the kinematics
corresponding to electron scattering at small angles and photon scattering at
large angles, where proton bremsstrahlung dominates. The analysis is based on
the direct evaluation method of the matrix elements in the so-called diagonal
spin basis. The results of numerical calculations for electron beam energy
$E_{e}=200 MeV$ in the above kinematics show that the relative contribution of
the Bethe-Heitler and interference terms to the reaction cross section is less
than 10 %, and the cross section for the reaction $ep \to ep \gamma$ is quite
sensitive to the proton polarizability. Owing to the factorization of the
squared electric and magnetic form factors of the proton, a compact expression
has been obtained for the differential cross section of the Bethe-Heitler
emission of a linearly polarized photon by an electron, taking into account the
proton recoil and form factors. A covariant expression has been obtained for
the lepton tensor in which contributions of states with transverse and
longitudinal polarizations of the virtual photon are separated.


title: Resummation and power corrections for factorized cross sections

abstract:
  Threshold resummation for factorizable cross sections in hadron-hadron
collisions has a number of applications and extensions. We discuss
factorization scale dependence, resummation at nonleading power in the moment
variable, and the implications of resummation for power corrections in the hard
momentum scale.


title: Newtonian gravity from Higgs condensates

abstract:
  We propose a description of {\it Newtonian} gravity as a long wavelength
excitation of the scalar condensate inducing electroweak symmetry breaking.
Indeed, one finds a $-{{G_F}\over{\eta}}{{m_im_j}\over{r}}$ long-range
potential where $G_F$ is the Fermi constant and $\eta\equiv
{{M^2_h}\over{2m^2}} $ is determined by the ratio between the Higgs mass $M_h$
and the mass m of the elementary quanta of the symmetric phase (`phions'). The
parameter $\eta$ would diverge in a true continuum theory so that its magnitude
represents a measure of non-locality of the underlying field theory. By
identifying $G\equiv {{G_F}\over{\eta}}$ with the Newton constant and assuming
the range of Higgs mass $M_h \sim 10^{2}-10^{3}$ GeV one obtains
$m=10^{-4}-10^{-5}$ eV and predicts typical `fifth-force' deviations below the
centimeter scale. Relation to Einstein gravity and string theory is discussed.
The crucial role of the first-order nature of the phase transition for the
solution of the so-called `hierarchy problem' is emphasized. The possible
relevance of the picture for the self-similarity of the universe and for a new
approach to the problem of dark matter is discussed.


title:
Identical Relations among Transverse Parts of Variant Green Functions
  and the Full Vertices in Gauge Theories

abstract:
  The identical relations among the transverse parts of variant vertex
functions are derived by computing the curl of the time-ordered products of
three-point Green functions involving the vector, the axial-vector and the
tensor current operators, respectively. These transverse relations are coupled
each other. Combining these transverse relations with the normal (longitudinal)
Ward-Takahashi identities forms a complete set of constraint relations for
three-point vertex functions. As a consequence, the full vector, the full
axial-vector and the full tensor vertex functions in the momentum space are
exactly obtained.


title: The Diagonalisation of the Lund Fragmentation Model I

abstract:
  We will in this note show that it is possible to diagonalise the Lund
Fragmentation Model. We show that the basic original result, the Lund Area law,
can be factorised into a product of transition operators, each describing the
production of a single particle and the two adjacent breakup points (vertex
positions) of the string field. The transition operator has a discrete spectrum
of (orthonormal) eigenfunctions, describing the vertex positions (which in a
dual way corresponds to the momentum transfers between the produced particles)
and discrete eigenvalues, which only depend upon the particle produced. The
eigenfunctions turn out to be the well-known two- dimensional harmonic
oscillator functions and the eigenvalues are the analytic continuations of
these functions to time-like values (corresponding to the particle mass). In
this way all observables in the model can be expressed in terms of analytical
formulas. In this note only the 1+1-dimensional version of the model is treated
but we end with remarks on the extensions to gluonic radiation, transverse
momentum generation etc, to be performed in future papers.


title: Chiral Symmetry Realization for Even- and Odd-parity Baryon Resonances

abstract:
  Baryon resonances with even and odd parity are collectively investigated from
the viewpoint of chiral symmetry(ChS). We propose a quartet scheme where
Delta's and N^*'s with even and odd parity form a chiral multiplet. This scheme
gives parameter-free constraints on the baryon masses in the quartet, which are
consistent with observed masses with spin 1/2, 3/2, 5/2. The scheme also gives
selection rules in the one-pion decay: The absence of the parity non-changing
decay N(1720) -> pi Delta(1232) is a typical example which should be confirmed
experimentally to unravel the role of ChS in baryon resonances.


title: Supersymmetry in Field Theory

abstract:
  Supersymmetric theories are reviewed in the context of field theories. The
gauge hierarchy problem in attempting the unification of all fundamental
interactions is the strongest motivation of modern development of
supersymmetry. Starting from the general notion of supersymmetry as a symmetry
between bosons and fermions, we explain how the supersymmetry becomes a part of
the space-time symmetry if we wish to maintain the relativisitic invariance.
The precise idea of supersymmetry is then introduced and the supersymmetric
field theories are formulated. There has been a significant breakthrough in the
study of nonperturbative effects in supersymmetric field theories using the
holomorphy and symmetry arguments. Some of these ideas and results are briefly
reviewed.


title: Hard jet probes in terms of colorless QCD dipoles

abstract:
  the forward jet playing the role of a hard probe is analyzed in terms of QCD
dipole (color-singlet q\bar q) configurations in the transverse position space.
There are sizable differences with the analogous q\bar q configurations of a
hard photon which may lead to significant phenomenological consequences on the
analysis of hard processes using a forward jet probe, e.g. at the Tevatron. A
geometrical interpretation of the resulting distribution in terms of black disk
diffraction is proposed.


title: QCD analysis of xF$_3$ at NNLO: the theoretical uncertainties

abstract:
  The next-to-next-to-leading order (NNLO) QCD analysis of the experimental
$xF_3$ structure function from CCFR data is performed. The theoretical
uncertainties of the analysis are discussed.


title: Off-diagonal generalized vector dominance in DIS and QCD

abstract:
  We review the generalized vector dominance (GVD) approach to DIS at small
values of the scaling variable, x. In particular, we concentrate on a recent
formulation of GVD that explicitly incorporates the configuration of the
gamma^* -> q qbar transition and a QCD-inspired ansatz for the (qqbar)p
scattering amplitude. The destructive interference, originally introduced in
off-diagonal GVD is traced back to the generic strcuture of two-gluon exchange.
Asymptotically, the transverse photoabsorption cross section behaves as (ln
Q^2)/Q^2, implying a logarithmic violation of scaling for F_2, while the
longitudinal-to-transverse ratio decreases as 1/\ln Q^2. We also briefly
comment on vector-meson production.


title:
Bounds on the Coupling of Light Pseudoscalars to Nucleons from Optical
  Laser Experiments

abstract:
  We find the following improved laboratory bounds on the coupling of light
pseudoscalars to protons and neutrons: $g_p^2/4\pi < 1.7 \times 10^{-9}$ and
$g_n^2/4\pi < 6.8 \times 10^{-8}$. The limit on $g_p$ arises since a nonzero
$g_p$ would induce a coupling of the pseudoscalar to two photons, which is
limited by experiments studying laser beam propagation in magnetic fields.
Combining our bound on $g_p$ with a recent analysis of Fischbach and Krause on
two-pseudoscalar exchange potentials and experiments testing the equivalence
principle, we obtain our limit on $g_n$. (PACS number(s):
14.20.Dh/14.80.-j/12.20.Fv/04.90.+e)


title: The experimental challenge of virtual compton scattering above 8 GeV

abstract:
  We discuss the experimental issues confronting measurements of the Virtual
Compton Scattering (VCS) reaction ep->ep gamma with electron beam energies 6-30
GeV. We specifically address the kinematics of Deeply Virtual Compton
Scattering (Deep Inelastic Scattering, with coincident detection of the
exclusive real photon nearly parallel to the virtual photon direction) and
large transverse momentum VCS (High energy VCS of arbitrary Q**2, and the
recoil proton emitted with high momentum transverse to the virtual photon
direction). We discuss the experimental equipment necessary for these
measurements. For the DVCS, we emphasize the importance of the
Bethe-Heitler-Compton interference terms that can be measured with the
electron-positron (beam charge) asymmetry, and the electron beam helicity
asymmetry.


title: On the Structure Functions of Mesons and Baryons in a Chiral Quark Model

abstract:
  This research summarizes work done by myself (Nucl.Phys.{\bf A641}
(1998)461), or in collaboration with R. M. Davidson (Phys.Lett.{\bf
B348}(1995)163) and H. Weigel and L. Gamberg (Nucl.Phys.{\bf B560}(1999)xx). I
will discuss several topics related with the computation of structure functions
in the quark model in general and its perturbative evolution. In particular, I
address this topic in the Nambu-Jona-Lasinio model of hadrons, where the
nucleon is constructed as a soliton. I show that the handling of the
regularization procedure is crucial in order to obtain exact scaling in the
Bjorken limit and fulfillment of sum rules. I also include some problems
concerning the general validity of quark model calculations.


title: Neutrinos in physics and astrophysics

abstract:
  An elementary general overview of the neutrino physics and astrophysics is
given. We start by a historical account of the development of our understanding
of neutrinos and how they helped to unravel the structure of the Standard
Model. We discuss why it is so important to establish if neutrinos are massive
and we introduce the main scenarios to provide them a mass. The present bounds
and the positive indications in favor of non-zero neutrino masses are discussed
as well as the major role they play in astrophysics and cosmology.


title: Born-form approximation for e+ e- to W+ W- to 4 fermions(+gamma)

abstract:
  We review the results on representing the differential cross section for
W-pair production, including W decay and hard-photon bremsstrahlung, in terms
of a Born-form approximation of fairly simple analytic form.


title:
Comment on the "Coupling Constant and Quark Loop Expansion for
  Corrections to the Valence Appeoximation" by Lee and Weingarten

abstract:
  Lee and Weingarten have recently criticized our calculation of quarkonium and
glueball scalars as being "incomplete" and "incorrect". Here we explain the
relation of our calculations to full QCD.


title:
Application of Hypervirial Theorem As Criteria For Accuracy of
  Variational Trial Wave Function

abstract:
  It would be interesting to investigate the accuracy of the results obtained
in the variational method, because it is important for studying hadron spectra.
One can define some criteria to judge the accuracy, or the quality of the trial
function. We employ a simple potential form to check how accurate the
variational results obtained by a single-parameter trial function can be. All
the concerned problems, in particular, the relevant aspects on the application
of hypervirial theorem in variational method for various potential forms, are
discussed in every detail. The qualitative conclusion of the work can be
generalized to much more complicated cases. Our study suggests that the
hypervirial relations can serve as a good and practical criterion for judging
the accuracy of any trial functions.


title:
Testing solar neutrino MSW oscillations at low delta m^2 through time
  variations of event rates in GNO and BOREXINO

abstract:
  The Mikheyev-Smirnov-Wolfenstein (MSW) explanation of the solar neutrino
problem is currently compatible with three distinct regions of the two-neutrino
oscillation parameter space (delta m^2,sin^2 2theta). We focus on the region
with the lowest value of delta m^2 (~10^{-7} eV^2), which implies significant
Earth regeneration effects for low-energy solar neutrinos. We point out that
such effects are not only observable as day-night variations of neutrino event
rates in the real-time BOREXINO experiment, but also as seasonal variations in
the radiochemical Gallium Neutrino Observatory (GNO) at Gran Sasso. We present
detailed calculations of the difference between winter and summer rates in GNO
(six months averages) in excess of the trivial seasonal variation due to the
Earth orbital eccentricity. We show that, within the low-delta m^2 MSW
solution, the net winter-summer GNO rate difference amounts to 4-6 SNU, with a
dominant contribution from pp neutrinos. We also give analytical expressions
for the winter and summer solar exposure functions at the Gran Sasso site.


title: Dynamics of Nontopological Solitons - Q Balls

abstract:
  We use numerical simulations and semi-analytical methods to investigate the
stability and the interactions of nontopological stationary qball solutions. In
the context of a simple model we map the parameter sectors of stability for a
single qball and verify the result using numerical simulations of time
evolution. The system of two interacting qballs is also studied in one and two
space dimensions. We find that the system generically performs breather type
oscillations with frequency equal to the difference of the internal qball
frequencies. This result is shown to be consistent with the form of the qball
interaction potential. Finally we perform simulations of qball scattering and
show that the right angle scattering effect observed in topological soliton
scattering in two dimensions, persists also in the case of qballs where no
topologically conserved quantities are present. For relativistic collision
velocities the qball charge is split into a forward and a right angle
scattering component. As the collision velocity increases, the forward
component gets amplified at the expense of the right angle component.
  The animated simulations of this study may be found on-line at the address
http://leandros.chem.demokritos.gr/qballs/index.html


title: A multiloop improvement of non-singlet QCD evolution equations

abstract:
  An approach is elaborated for calculation of "all loop" contributions to the
non-singlet evolution kernels from the diagrams with renormalon chain
insertions. Closed expressions are obtained for sums of contributions to
kernels $P(z)$ for the DGLAP equation and $V(x,y)$ for the "nonforward" ER-BL
equation from these diagrams that dominate for a large value of $b_0$, the
first $\beta$-function coefficient. Calculations are performed in the covariant
$\xi$-gauge in a MS-like scheme. It is established that a special choice of the
gauge parameter $\xi=-3$ generalizes the standard "naive nonabelianization"
approximation. The solutions are obtained to the ER-BL evolution equation
(taken at the "all loop" improved kernel), which are in form similar to
one-loop solutions. A consequence for QCD descriptions of hard processes and
the benefits and incompleteness of the approach are briefly discussed.


title: Electroweak Precision Tests

abstract:
  Precision measurements of electroweak observables provide stringent tests of
the Standard Model structure and an accurate determination of its parameters.
An overview of the present experimental status is presented.


title: The first fermi in a high energy nuclear collision

abstract:
  At very high energies, weak coupling, non-perturbative methods can be used to
study classical gluon production in nuclear collisions. One observes in
numerical simulations that after an initial ``formation'' time, the produced
partons are on shell, and their subsequent evolution can be studied using
transport theory. At the initial formation time, a simple non-perturbative
relation exists between the energy and number densities of the produced
partons, and a scale determined by the saturated parton density in the nucleus.


title: U(2) Flavor Physics without U(2) Symmetry

abstract:
  We present a model of fermion masses based on a minimal, non-Abelian discrete
symmetry that reproduces the Yukawa matrices usually associated with U(2)
theories of flavor. Mass and mixing angle relations that follow from the simple
form of the quark and charged lepton Yukawa textures are therefore common to
both theories. We show that the differing representation structure of our
horizontal symmetry allows for new solutions to the solar and atmospheric
neutrino problems that do not involve modification of the original charged
fermion Yukawa textures, or the introduction of sterile neutrinos.


title: Temperature Power Law of Equilibrium Heavy Particle Density

abstract:
  A standard calculation of the energy density of heavy stable particles that
may pair-annihilate into light particles making up thermal medium is performed
to second order of coupling, using the technique of thermal field theory. At
very low temperatures a power law of temperature is derived for the energy
density of the heavy particle. This is in sharp contrast to the exponentially
suppressed contribution estimated from the ideal gas distribution function. The
result supports a previous dynamical calculation based on the Hartree
approximation, and implies that the relic abundance of dark matter particles is
enhanced compared to that based on the Boltzmann equation.


title: New physics effects in $\epsilon'/\epsilon$

abstract:
  After presenting an optimistic prediction for the CP-violating parameter
$\epsilon'/\epsilon$ in the standard model, we provide an analysis on new
physics effects in $\epsilon'/\epsilon$.


title:
Signatures of the anomalous $Z\gamma$ and ZZ production at the lepton
  and hadron Colliders

abstract:
  The possible form of New Physics (NP) interactions affecting the ZZZ, $ZZ
\gamma$ and $Z\gamma \gamma$ vertices, is critically examined. Their signatures
and the possibilities to study them, through ZZ and $Z\gamma$ production, at
the e^-e^+ Colliders LEP and LC and at the hadronic Colliders Tevatron and LHC,
are investigated. Experimental limits obtained or expected on each coupling are
collected. A simple theoretical model based on virtual effects due to some
heavy fermions is used for acquiring some guidance on the plausible forms of
these NP vertices. In such a case specific relations among the various neutral
couplings are predicted, which can be experimentally tested and possibly used
to constrain the form of the responsible NP structure.


title: A New Approach to Weak Amplitudes in Large-Nc QCD

abstract:
  We report on some recent progress made in understanding weak matrix elements
of mesons in the context of the next-to-leading order of the large-Nc
approximation to QCD. Specifically, we first use the example of the weak
contributions to the pi^+ - pi^0 mass difference to exhibit how a systematic
matching can be achieved analytically between short distances and long
distances within our large-Nc framework. We are then also able to compute
matrix elements of the operator Q_7, as they turn out to depend on the same QCD
correlator as the previous pion mass difference. As a final example we
determine the chiral counterterms governing the pseudoscalar decay into a
lepton pair, where we briefly comment also on the special case K_L -> mu^+
mu^-.


title: Tests of the Standard Model at HERA

abstract:
  We review how experimental data collected at the HERA lepton-hadron collider
have improved our theoretical and phenomenological understanding of the
standard model, and specifically of its QCD sector.


title: Hadrons Without Strings

abstract:
  Descriptions of hadrons and glueballs can be constructed using strings to
preserve gauge invariance. We show how this string dependence may be removed to
all orders in perturbation theory.


title: Heavy Quarkonium

abstract:
  Bound states of heavy $\bar{q}q$ quarks are reviewed within the context of
QCD. First of all, we consider the calculations which can be performed {\sl ab
initio}, which includes $\bar{t}t$ with principal quantum number $n$ up to
four,
  $\bar{b}b$ states with $n=1$ and (to a lesser extent)
  $\bar{b}b$ with $n=2$ and $\bar{c}c$ for $n=1$. Among the results, we report
a very precise $O(\alpha_s^4)$ evaluation of $b, c$ quark masses from
quarkonium spectrum with a potential to two loops, a calculation of the decay
$\Upsilon\to e^+e^-$ and a prediction for the splitting $\Upsilon - \eta_b$. We
then consider how, with the help of reasonable assumptions, one can extend QCD
calculations to other states of heavy quarks. Finally, a few words are said on
the treatment of light quark bound states.


title: Supersymmetric Higgs pair discovery prospects at hadron colliders

abstract:
  We study the potential of hadron colliders in the search for the pair
production of neutral Higgs bosons in the framework of the Minimal
Supersymmetric Standard Model. Using analytical expressions for the relevant
amplitudes, we perform a detailed signal and background analysis, working out
efficient kinematical cuts for the extraction of the signal. The important role
of squark loop contributions to the signal is emphasised. If the signal is
sufficiently enhanced by these contributions, it could even be observable at
the next run of the upgraded Tevatron collider in the near future. At the LHC
the pair production of light and heavy Higgs bosons might be detectable
simultaneously.


title: A Model for the Parton Distribution in Nuclei

abstract:
  We have extended recently proposed model of parton distribution i nucleons to
the case of nucleons in nuclei.


title: On the Domain of Mixing Angles in Three Flavor Neutrino Oscillations

abstract:
  We clarify the domain needed for the mixing angles in three flavor neutrino
oscillations. By comparing the ranges of the transition probabilities as
functions of the domains of the mixing angles, we show that it is necessary and
sufficient to let all mixing angles be in $[ 0, \pi/2 ]$. This holds
irrespectively of any assumptions on the neutrino mass squared differences.


title:
Optimal polarized observables for model-independent new-physics search
  at e+e- colliders

abstract:
  For the processes e+e-\to \mu+\mu-, \tau+\tau-, b\bar{b} and c\bar{c} at a
future e+e- collider with \sqrt{s}=0.5 TeV, we examine the sensitivity of the
helicity cross sections to four-fermion contact interactions. If longitudinal
polarization of the electron beam were available, two polarized integrated
cross sections would offer the opportunity to separate the helicity cross
sections and, in this way, to derive model-independent bounds on the relevant
parameters. The measurement of these polarized cross sections with optimal
kinematical cuts could significantly increase the sensitivity of helicity cross
sections to contact interaction parameters and could give crucial information
on the chiral structure of such new interactions.


title: Future of Heavy-Flavour Physics

abstract:
  The prospects for the coming Golden Age of heavy-flavour physics are
discussed from the perspective of one who hopes it may provide a window onto
physics beyond the Standard Model. Precise QCD calculations are necessary for
accurate determinations of CKM parameters, and may be provided by the lattice
and new perturbative techniques. The future of CKMology in the wake of the
relatively small branching ratio for B_d -> pi pi are discussed, including
alternative strategies for measuring alpha and gamma. The opportunities for
measurements of rare B decays are reviewed briefly, as are possible K-decay
windows on physics beyond the Standard Model, in the wake of the establishment
of a relatively large value for epsilon'/epsilon. Finally, relations to other
aspects of flavour physics are discussed, including the grand unification of
quark and lepton masses in the context of neutrino-mass models motivated by the
recent oscillation data from Super-Kamiokande and elsewhere.


title: A Tale of Two Hard Pomerons

abstract:
  Two mechanisms are examined for hard double pomeron exchange dijet
production, the factorized model of Ingelman-Schlein and the nonfactorized
model of lossless jet production which exhibits the Collins-Frankfurt-Strikman
mechanism. Comparison between these two mechanisms are made of the total cross
section, $E_T$-spectra, and mean rapidity spectra. For both mechanisms, several
specific models are examined with the cuts of CDF, D\O and representative cuts
of LHC. Distinct qualitative differences are predicted by the two mechanisms
for the CDF $y_+$-spectra and for the $E_T$-spectra for all three experimental
cuts. The preliminary CDF and D\O experimental data for this process are
interpreted in terms of these two mechanisms. The $y_+$-spectra of the CDF data
is suggestive of domination by the factorized Ingelman-Schlein mechanism,
whereas the D\O data shows no greater preference for either mechanism. An
inconsistency is found amongst all the theoretical models in attempting to
explain the ratio of the cross sections given by the data from these two
experiments.


title:
Ratio of Hadronic Decay Rates of J\psi and \psi(2S) and the \rho\pi
  Puzzle

abstract:
  The so-called \rho\pi puzzle of J\psi and \psi(2S) decays is examined using
the experimental data available to date. Two different approaches were taken to
estimate the ratio of J\psi and \psi(2S) hadronic decay rates. While one of the
estimates could not yield the exact ratio of \psi(2S) to J\psi inclusive
hadronic decay rates, the other, based on a computation of the inclusive ggg
decay rate for
  \psi(2S) (J\psi) by subtracting other decay rates from the total decay rate,
differs by two standard deviations from the naive prediction of perturbative
QCD, even though its central value is nearly twice as large as what was naively
expected. A comparison between this ratio, upon making corrections for specific
exclusive two-body decay modes, and the corresponding experimental data
confirms the puzzles in
  J\psi and \psi(2S) decays. We find from our analysis that the exclusively
reconstructed hadronic decays of the \psi(2S) account for only a small fraction
of its total decays, and a ratio exceeding the above estimate should be
expected to occur for a considerable number of the remaining decay channels. We
also show that the recent new results from the BES experiment provide crucial
tests of various theoretical models proposed to explain the puzzle.


title: VEP oscillation solutions to the solar neutrino problem

abstract:
  We study the solar neutrino problem within the framework of a parametrized
post-Newtonian formulation for the gravitational interaction of the neutrinos,
which incorporates a violation to the equivalence principle (VEP). Using the
current data on the rates and the energy spectrum we find two possible
oscillation solutions, both for a large mixing angle. One of them involves the
MSW effect in matter and the other corresponds to vacuum oscillations. An
interesting characteristic of this mechanism is that it predicts a semi-annual
variation of the neutrino flux. Our analysis provides new constraints for some
VEP parameters.


title: Non universal gaugino phases and the LSP relic density

abstract:
  The cosmological relic density of the lightest supersymmetric particle (LSP)
of type I string derived model is calculated. This model can accommodate large
values of CP violating phases, and the electron and neutron electric dipole
moments satisfy the experimental constraint. We show that the constraint from
the electric dipole moment on the ratio between the gaugino masses implies that
the mass of the LSP, which is bino like, is close to the lightest chargino. The
co-annihilation between them is very important to reduce the LSP relic density
to an interesting region. We show that the SUSY phases, although they are
large, have no significant effect on the relic density and on the the upper
bound imposed on the LSP mass. However, they are very significant for the
detection rates. We emphasize that the phase of the trilinear coupling increase
the direct and indirect detection rates.


title:
Neutralino Inelastic Scattering with Subsequent Detection of Nuclear
  Gamma Rays

abstract:
  We consider the potential benefits of searching for supersymmetric
dark-matter through its inelastic excitation, via the "scalar current", of
low-lying collective nuclear states in a detector. If such states live long
enough so that the gamma radiation from their decay can be separated from the
signal due to nuclear recoil, then background can be dramatically reduced. We
show how the kinematics of neutralino-nucleus scattering is modified when the
nucleus is excited and derive expressions for the form factors associated with
exciting collective states. We apply these results to two specific cases: 1)
the 5/2^+ state at 13 keV in 73Ge, and 2) the rotational and hence very
collective state 3/2^+ at 8 keV in 169Tm (even though observing the transition
down from that state will be difficult). In both cases we compare the form
factors for inelastic scattering with those for elastic scattering. The
inelastic cross section is considerably smaller than its elastic counterpart,
though perhaps not always prohibitively so.


title: Inflationary Cosmology: Progress and Problems

abstract:
  These lecture notes intend to form a short pedagogical introduction to
inflationary cosmology, highlighting selected areas of recent progress such as
reheating and the theory of cosmological perturbations. Problems of principle
for inflationary cosmology are pointed out, and some new attempts at solving
them are indicated, including a nonsingular Universe construction by means of
higher derivative terms in the gravitational action, and the study of
back-reaction of cosmological perturbations.


title:
Gluon penguin enhancements to inclusive charmless decays of b quark in
  the 2HDM with flavor changing couplings

abstract:
  We calculate the enhancements to the inclusive charmless decays of b quark,
$b \to s g, s q\bar{q}, sgg$, from gluon penguin diagrams induced by the
charged and neutral Higgs bosons $(H^{\pm}, h^0, H^0$, and A^0) in the
Two-Higgs-Doublet Model with flavor-changing couplings. Within the considered
parameter space, the new contributions from charged Higgs boson are dominant.
After including the new contributions, the branching ratio $BR(b \to sg)$ (q^2
=0) can be increased form $\sim 0.2%$ in the standard model to 4.4% and 2.6% in
the two-Higgs-doublet model for $m_{H^+}=100$ and 200 GeV, respectively. The
new contribution to the decay mode $b \to s q \bar{q}$ with q=(u,d,s) is,
however, numerically small and peaked at the lower q^2 region. The new
contribution to $b \to s gg$ can also be neglected.


title: Soft-Gluon Resummation in Heavy Quarkonium Physics

abstract:
  Soft-gluon resummation within the framework of heavy quarkonium
hadroproduction is considered. A few selected cases are studied in detail. A
sizeable increase of the cross sections with respect to the next-to-leading
order predictions with central factorization/renormalization scale choice can
generally be observed. Improvements in the dependence of the cross sections on
the two scales, especially when they are kept equal, are also found.


title: Gluonic states in two space dimensions

abstract:
  We discuss the ``spectroscopy'' of gluonic states in systems with two space
dimensions, using simple models to mimic the results of lattice gauge theory
computations. We first discuss the quantum numbers of these systems, including
charge conjugation. Two types of systems are discussed in detail: ``gluelumps''
which have a heavy adjoint color charge at the origin and glueballs which are
composed entirely of glue. Both systems are discussed using the bag model and
the flux tube model. For glueballs the model spectra are compared with the
resulst of Teper. Both models capture many features of the numerical results.


title: Interjet Rapidity Gaps in Perturbative QCD

abstract:
  We discuss a formalism in which high-$p_T$ dijet rapidity gaps are identified
by energy flow in the interjet region. When the gap energy, $Q_{\rm gap}$, is
sufficiently large, the cross section may be computed from standard
factorization theorems. For $p_T\gg Q_T\gg\Lambda_{\rm QCD}$, this is a
two-scale perturbative problem, in which we may resum logarithms of $Q_{\rm
gap}/p_T$. The cross section computed as a function of $Q_{\rm gap}$ reproduces
many of the features of the Tevatron dijet gap data. The factorized cross
section gives meaning to the color content of the hard scattering.


title:
Models of Low Energy Effective Theory applied to Kaon Non-leptonic
  Decays and Other Matrix Elements

abstract:
  In this talk I describe work on computing non-leptonic matrix elements
consistently with both long and short distance contributions included. On the
simpler example of the $\pi^+$-$\pi^0$ mass difference I explain in detail the
matching procedure and the difference between various low-energy models. I then
explain the new difficulties in non-leptonic Kaon decays and how the matching
here can in principle be done in the same way when scheme dependences are
correctly accounted for. In the end I summarize the results J. Prades and I
obtain for the $\Delta I=1/2$ rule and $B_6$.


title: Determination of sparticle masses and SUSY parameters

abstract:
  A case study will be presented to determine the particle masses and
parameters of a specific mSUGRA model at the TESLA Linear Collider with high
precision.


title: Future of Heavy Flavour Physics: Experimental Perspective

abstract:
  I discuss what measurements need to be done to search for physics beyond the
Standard CKM model, rather than just what studies can be done in the near
future. It is also important to accurately measure the CKM matrix elements.
Current best estimates for two important elements are:
  |V_{cb}|=0.0381 +/- 0.0021 and |V_{ub}/V_{cb}|=0.085 +/- 0.019. Finally,
future experiments are discussed.


title: Isospin Violation in Hyperon Semileptonic Decays

abstract:
  This note emphasizes that due to isospin violation the two central states in
the octet mix, and this mixing can be measured in semileptonic decays, in
particular with an accurate determination of the sigma plus semileptonic
branching ratio.


title: Fractional Quantum Mechanics and Levy Path Integrals

abstract:
  The fractional quantum and statistical mechanics have been developed via new
path integrals approach.


title:
General RG Equations for Physical Neutrino Parameters and their
  Phenomenological Implications

abstract:
  The neutral leptonic sector of the Standard Model presumably consists of
three neutrinos with non-zero Majorana masses with properties further
determined by three mixing angles and three CP-violating phases. We derive the
general renormalization group equations for these physical parameters and apply
them to study the impact of radiative effects on neutrino physics. In
particular, we examine the existing solutions to the solar and atmospheric
neutrino problems, derive conclusions on their theoretical naturalness, and
show how some of the measured neutrino parameters could be determined by purely
radiative effects. For example, the mass splitting and mixing angle suggested
by solar neutrino data could be entirely explained as a radiative effect if the
small angle MSW solution is realized. On the other hand, the mass splitting
required by atmospheric neutrino data is probably determined by unknown physics
at a high energy scale. We also discuss the effect of non-zero CP-violating
phases on radiative corrections.


title: Evolution of parton distributions with truncated Mellin moments

abstract:
  Evolution equations for parton distributions can be approximately
diagonalized and solved in moment space without assuming any knowledge of the
parton distribution in the region of small x. The evolution algorithm for
truncated moments is simple and rapidly converging. Examples of applications
are outlined.


title:
Momentum expansion of massive two-loop Feynman graphs around a finite
  value

abstract:
  We give an algorithm for obtaining expansions of massive two-loop Feynman
graphs in powers of the external momentum around a finite, nonzero value of the
momentum. This is based on our general two-loop formalism to reduce massive
two-loop graphs with renormalizable interactions into a standard set of special
functions. After the algebraic reduction, the final results are obtained by
numerical integration. We apply the expansion algorithm to treat the
top-dependent corrections of O(g^2 alpha_s) to the b quark self-energy and
extract its momentum expansion on-shell.


title: Charmonium Decay Physics

abstract:
  Recent experimental results on the decays of charmonium, together with
related physics issues, are reviewed. Some future prospects are described.


title:
Gauge dependence and matching procedure of a nonrelativistic QED/QCD
  boundstate formalism

abstract:
  A nonrelativistic boundstate formalism used in contemporary calculations is
investigated. It is known that the effective Hamiltonian of the boundstate
system depends on the choice of gauge. We obtain the transformation charge Q of
the Hamiltonian for an arbitrary infinitesimal change of gauge, by which gauge
independence of the mass spectrum and gauge dependences of the boundstate wave
functions are dictated. We give formal arguments based on the BRST symmetry
supplemented by power countings of Coulomb singularities of diagrams. For
illustration: (1)we calculate Q up to O(1/c), (2)we examine gauge dependences
of diagrams for a decay of a qqbar boundstate up to O(1/c) and show that
cumbersome gauge cancellations can be circumvented by directly calculating Q.
As an application we point out that the present calculations of top quark
momentum distribution in the ttbar threshold region are gauge dependent. We
also show possibilities for incorrect calculations of physical quantities of
boundstates when the on-shell matching procedure is employed. We give a proof
of a justification for the use of the equation of motion to simplify the form
of a local NRQCD Lagrangian. The formalism developed in this work will provide
useful cross checks in computations involving NRQED/NRQCD boundstates.


title:
New Kinetic Equation for Pair-annihilating Particles: Generalization of
  the Boltzmann Equation

abstract:
  A convenient form of kinetic equation is derived for pair annihilation of
heavy stable particles relevant to the dark matter problem in cosmology. The
kinetic equation thus derived extends the on-shell Boltzmann equation in a most
straightforward way, including the off-shell effect. A detailed balance
equation for the equilibrium abundance is further analyzed. Perturbative
analysis of this equation supports a previous result for the equilibrium
abundance using the thermal field theory, and gives the temperature power
dependence of equilibrium value at low temperatures. Estimate of the relic
abundance is possible using this new equilibrium abundance in the sudden
freeze-out approximation.


title: Deeply virtual electroproduction of photons and mesons on the nucleon

abstract:
  We give predictions for the leading order amplitudes for deeply virtual
Compton scattering and hard meson electroproduction reactions at large Q^2 in
the valence region in terms of skewed quark distributions. We give first
estimates for the power corrections to these leading order amplitudes. In
particular, we outline examples of experimental opportunities to access the
skewed parton distributions at the current high-energy lepton facilities :
JLab, HERMES and COMPASS.


title: Higher Order Polarizabilities of the Proton

abstract:
  Compton scattering results are used to probe proton structure via measurement
of higher order polarizabilities. Values for
$\alpha_{E2}^p,\beta_{E2}^p,\alpha_{E\nu}^p,$ $\beta_{E\nu}^p$ determined via
dispersion relations are compared to predictions based upon chiral symmetry and
from the constituent quark model. Extensions to spin-polarizabilities are also
discussed.


title:
Three Flavor Neutrino Oscillations and Application to Long Baseline
  Experiments

abstract:
  Using the result of the three flavor analysis of the old Kamiokande data, the
recent Superkamiokande data of atmospheric neutrinos and the CHOOZ reactor
data, it is shown that the third mixing angle $\theta_{13}$ is small. It is
proposed to determine the small value of $\theta_{13}$ and the CP violating
phase $\delta$ in very long baseline experiments by measuring the appearance
probability $P(\nu_\mu\to\nu_e)$ and the T violating effect
$P(\nu_e\to\nu_\mu)-P(\nu_\mu\to\nu_e)$ which are enhanced by the matter effect
of the Earth.


title: Scheme Independence of $g_1^p (x, Q^2)$

abstract:
  We work with two general factorization schemes in order to explore the
consequences of imposing scheme independence on $g_1^p (x, Q^2)$. We see that
although the light quark sector is indifferent to the choice of a particular
scheme, the extension of the calculations to the heavy quark sector indicates
that a scheme like the $\bar{MS}$ is preferable.


title:
On the Dynamical Symmetry Breaking of the Electroweak Interactions by
  the Top Quark

abstract:
  We discuss the electroweak gauge symmetry breaking triggered by a new strong
attractive interaction to condensate fermion-antifermion, and topcolor is a
prototype. To deal with the fermion pairing, a general method based on the
Hubbard-Stratonovich transformation in the functional integral approach is
used.
  We derive a formula which relates the $W^\pm$, $Z^0$ weak boson masses to
that of the condensated fermion, thus generalizing the Pagels-Stokar formula
obtained in QCD. The custodial SU(2) electroweak symmetry turns out to be
systematically violated, the deviation of $\rho\equiv
M_W^2/(M_Z^2\cos^2\theta_W) $ from unity is related to the new physics scale
$\Lambda$. Some phenomenological consequences of the top-pair condensation
models are discussed. Distinctive signatures of the $\bar{t}t$ scalar bound
state, a Higgs boson like denoted by $H_t$, are the dominant decay modes
$H_t\to \Upsilon +\gamma ,$ $H_t\to \Upsilon +Z^0$, and $H_t \to B^*
+\bar{B}^*$.


title: Reconstruction of Basic Parameters from Chargino Production

abstract:
  The event characteristics of chargino pair production at e+e- collisions are
explored to determine gaugino-higgsino mixing angles. We demonstrate that by
measuring total cross sections and left-right asymmetries with polarized beams
or angular correlations among chargino decay products the fundamental SUSY
parameters M_2, \mu and tan(beta) can be uniquely determined in a model
independent way.


title: The bootstrap for impact factors and the gluon wave function

abstract:
  Using the results recently obtained for the non-forward quark and gluon
impact factors, it is shown that their form in the gluon colour channel is
consistent with the ``third bootstrap condition'', namely, that they should be
proportional to the gluon wave function. The gluon wave function found from
this assumption is used to write the full bootstrap condition for the gluonic
potential in the next-to-leading order.


title: Comment on "New conditions for a total neutrino conversion in a medium"

abstract:
  We show that the conditions for total neutrino conversion found in [1] are
equivalent to the conditions of maximal depth (parametric resonance) and
($\pi/2 + \pi k$) - phase of parametric oscillations. Therefore the effects
considered in [1] are a particular case of the parametric resonance in neutrino
oscillations. The existence of strong enhancement peaks in transition
probability P rather than the condition P=1 is of physical relevance. We
comment on possible realizations and implications of the parametric enhancement
of neutrino oscillations.


title: Decay Constants and Semileptonic Form Factors of Pseudoscalar Mesons

abstract:
  A relativistic constituent quark model is adopted to give an unified
description of the leptonic and semileptonic decays of pseudoscalar mesons
(\pi, K, D, D_s, B, B_s). The calculated leptonic decay constants and form
factors are found to be in good agreement with available experimental data and
the results of other approaches. Eventually, the model is found to reproduce
the scaling behaviours of spin-flavor symmetry in the heavy-quark limit.


title: Constraints on R-parity violating couplings from lepton universality

abstract:
  We analyze the one loop corrections to leptonic W and Z decays in an R-parity
violating extension to the Minimal Supersymmetric Standard Model (MSSM). We
find that lepton universality violation in the Z line-shape variables alone
would strengthen the bounds on the magnitudes of the lambda' couplings, but a
global fit on all data leaves the bounds virtually unchanged at |lambda'_{33k}|
< 0.42 and |lambda'_{23k}| < 0.50 at the 2 sigma level. Bounds from W decays
are less stringent: |lambda'_{33k}| < 2.4 at 2 sigma, as a consequence of the
weaker Fermilab experimental bounds on lepton universality violation in W
decays. We also point out the potential of constraining R-parity violating
couplings from the measurement of the Upsilon invisible width.


title:
Signal of partial U_A(1) symmetry restoration from two-pion
  Bose-Einstein correlations

abstract:
  The intercept parameter of the two-pion Bose-Einstein correlation functions
at low transverse momentum is shown to play the role of an experimentally
accessible measure of the (partial) restoration of U_A(1) symmetry in
ultra-relativistic nuclear collisions.