title: SUSY GUTs under Siege : Proton Decay

abstract:
  SO(10) supersymmetric grand unified theories [SUSY GUTs] provide a beautiful
framework for physics beyond the standard model. Experimental measurements of
the three gauge couplings are consistent with unification at a scale $M_G \sim
3 \times 10^{16}$ GeV. In addition predictive models for fermion masses and
mixing angles have been found which fit the low energy data, including the
recent data for neutrino oscillations. SO(10) boundary conditions can be tested
via the spectrum of superparticles. The simplest models also predict neutron
and proton decay rates. In this paper we discuss nucleon decay rates and obtain
reasonable upper bounds. A clear picture of the allowed SUSY spectra as
constrained by nucleon decay is presented.


title: Matter effects in the D0-D0bar system

abstract:
  We discuss the impact of matter effects in the D0-D0bar system. We show that
such effects could, in principle, be measured, but that they cannot be used to
probe the mass difference x_D or the lifetime difference y_D. This occurs
because the mixing effects and the matter effects decouple at short times. We
also comment briefly on the B systems.


title: Strangeness enhancement from strong color fields at RHIC

abstract:
  In ultra-relativistic heavy ion collisions, early stage multiple scatterings
may lead to an increase of the color electric field strength. Consequently,
particle production - especially heavy quark (and di-quark) production - is
greatly enhanced according to the Schwinger mechanism. We test this idea via
the Ultra-relativistic Quantum Molecular Dynamics model (UrQMD) for Au+Au
collisions at the full RHIC energy ($\sqrt{s} = 200$ AGeV). Relative to p+p
collisions, a factor of 60, 20 and 7 enhancement respectively, for $\Omega$
($sss$), $\Xi$ ($ss$), and $\Lambda$, $\Sigma$ ($s$) is predicted for a model
with increased color electric field strength.


title: Filter for strangeness in J^{PC} exotic four-quark states

abstract:
  Symmetrization selection rules for the decay of four-quark states to two J=0
mesons are analysed in a non - field theoretic context with isospin symmetry.
The OZI allowed decay of an isoscalar J^PC = (1,3,...)^{-+} exotic state to
eta' eta or f_0' f_0 is only allowed for four-quark components of the state
containing one s sbar pair, providing a filter for strangeness content in these
states. Decays of four-quark a_0 states are narrower than otherwise expected.
If the experimentally observed 1^{-+} enhancement in eta pi is resonant, it is
qualitatively in agreement with being a four-quark state.


title: Anomalous magnetic moment of a bound electron

abstract:
  We study binding corrections to the gyromagnetic factor g_e of an electron in
hydrogen-like ions. We argue that the leading order binding effects in
radiative corrections Delta g_rad are universal to all orders in alpha/pi and
the complete result reads Delta g_rad = (g_free - 2) [1+(Z alpha)^2/6] +
O[alpha/pi (Zalpha)^4]. The theoretical uncertainty in the prediction for the
experimentally interesting carbon ion is decreased by a factor of about 3.


title: Prospects for Spin Physics at RHIC

abstract:
  Colliding beams of 70% polarized protons at up to $\sqrt{s}$=500 GeV, with
high luminosity, L=2$\times10^{{\rm 32}}$ cm$^{-2}$sec$^{-1}$, will represent a
new and unique laboratory for studying the proton. RHIC-Spin will be the first
polarized-proton collider and will be capable of copious production of jets,
directly produced photons, and $W$ and $Z$ bosons. Features will include direct
and precise measurements of the polarization of the gluons and of $\bar{u}$,
$\bar{d}$, $u$, and $d$ quarks in a polarized proton. Parity violation searches
for physics beyond the standard model will be competitive with unpolarized
searches at the Fermilab Tevatron. Transverse spin will explore transversity
for the first time, as well as quark-gluon correlations in the proton. Spin
dependence of the total cross section and in the Coulomb nuclear interference
region will be measured at collider energies for the first time. These
qualitatively new measurements can be expected to deepen our understanding of
the structure of matter and of the strong interaction.


title: Backreaction and the Parametric Resonance of Cosmological Fluctuations

abstract:
  We study the class of two-field inflationary Universe models \lambda\phi^4/4
+ g^2\chi^2\phi^2/2, in which parametric resonance during the initial stages of
reheating can lead to an exponential amplification of the amplitude of
cosmological fluctuations. Employing both analytical arguments and numerical
simulations, we determine the time at which backreaction of fluctuations on the
background fields shuts off the exponential growth, making use of the Hartree
approximation, and including scalar metric perturbations. For the case
g^2/\lambda=2, we find that the amplitude of fluctuations after preheating will
exceed the observational upper bound independent of the value of \lambda,
unless the duration of inflation is very long. Cosmological fluctuations are
acceptably small for g^2/\lambda>=8. We also find that the addition of
\chi-field self-interaction can limit the growth of fluctuations, and in the
negative-coupling case the system can become effectively single-field, removing
the resonance.


title:
R-parity violation in $(t+\bar t)\tilde g$ production at LHC and
  Tevatron

abstract:
  We study the production of $(t+\bar{t}) \tilde{g}$ at the hadron colliders in
an R-parity ($R_{p}$) violating supersymmetric model. This process provides us
with information not only about $R_{p}$ violation, but may also help us in
detecting the supersymmetry itself. It is possible to detect an $R_{p}$
violating signal (with single gluino production) at the future hadron
colliders, such as Fermilab Tevatron Run II or CERN Large Hadron Collider
(LHC), if the parameters in the supersymmetric $\rlap/ R_{p}$ interactions are
not too small, e.g. for $m_{\tilde{g}}=1$ TeV, $\lambda^{''}=0.1$, still
hundreds of events are produced at LHC with luminosity $30 fb^{-1}$. Even if we
could not detect a signal of $ \rlap/R_{p}$ in the experiment, we get stringent
constraints on the heavy flavour $\rlap/R_{p}$ couplings. In addition to the
minimal supersymmetric standard model we have also considered some models with
a heavy gluino as the lightest supersymmetric particle.


title:
Parallelizing the Symbolic Manipulation Program FORM Part I: Workstation
  Clusters and Message Passing

abstract:
  The present paper is the first of a series of papers reporting on the
parallelization of the symbolic manipulation program FORM on different parallel
architectures. Part I deals with workstation clusters using dedicated network
hardware and the messages passing libraries (MPI and PVM). After a short
introduction to the sequential version of FORM a detailed analysis of the
different platforms used is given and the structure of the parallel version of
FORM is explained. The forthcoming part II will describe the parallelization of
FORM on SMP (symmetrical multi-processing) architectures.


title:
Impact of e^+ and e^- Beam Polarization on Chargino and Neutralino
  Production at a Linear Collider

abstract:
  We study the production processes e^+ e^- -> chi^+_i chi^-_j, i,j=1,2, and
e^+ e^- -> chi^0_m chi^0_n, m,n=1,...,4, working out the advantages of
polarizing both beams. For e^+ e^- -> chi^+_1 chi^-_1 with chi^-_1 -> chi^0_1
e^- nu and e^+ e^- -> chi^0_1 chi^0_2 with chi^0_2 -> chi^0_1 e^+ e^- we
perform a detailed analysis, including the complete spin correlations between
production and decay. We analyze the forward--backward asymmetry of the decay
electron for various beam polarizations. We also study polarization asymmetries
in e^+ e^- -> chi^0_1 chi^0_2. These asymmetries strongly constrain the gaugino
parameter M_1 and the masses m_{\tilde{e}_L}, m_{\tilde{e}_R}, m_{\tilde{nu}}
also if m_{\tilde{e}_{L,R}}, m_{\tilde{nu}} > sqrt{s}/2. We give numerical
predictions for three scenarios for a linear collider with sqrt{s}=500-1000
GeV.


title: Field correlators in QCD. Theory and applications

abstract:
  This review is aimed to demonstrate the basics and use of formalism of
gauge-invariant nonlocal correlators in nonabelian gauge theories. Many
phenomenologically interesting nonperturbative aspects of gluodynamics and QCD
can be described in terms of correlators of the nonabelian field strength
tensors. It is explained how the properties of correlator ensemble encode the
structure of QCD vacuum and determine different nonperturbative observables. It
is argued that in gluodynamics and QCD the dominant role is played by the
lowest nontrivial two-point correlator (Gaussian dominance). Lattice
measurements of field correlators are discussed. Important for the formalism
theoretical tools, such as nonabelian Stokes theorem, background perturbation
theory, cluster expansion, as well as phenomenological applications to the
heavy quarkonium dynamics and QCD phase transition are reviewed.


title:
Logarithmic SUSY electroweak effects on four-fermion processes at TeV
  energies

abstract:
  We compute the MSSM one-loop contributions to the asymptotic energy behaviour
of fermion-antifermion pair production at future lepton-antilepton colliders.
Besides the conventional logarithms of Renormalization Group origin, extra SUSY
linear logarithmic terms appear of "Sudakov-type". In the TeV range their
overall effect on a variety of observables can be quite relevant and
drastically different from that obtained in the SM case.


title: Compositeness Condition and Vacuum Stability

abstract:
  We consider what occurs when we remove one of the compositeness conditions
proposed by Bardeen, Hill and Lindner that leads to predictions for the top
quark mass conflicting with the experimental value. Through this consideration
the condition for the Higgs particle to be the composite particle is
reconsidered. We show that in this case, (I) the Higgs-Yukawa system of the
standard model becomes equivalent to a non-local four-fermi system at a
high-energy scale $\Lambda$, (II) The Higgs-Yukawa sector of the model becomes
useless above the scale because the vacuum state cannot be defined. We regard
the two phenomena as indications of the compositeness of the Higgs particle. It
is suggested that the new physics above $\Lambda$ contains bi-local fields.


title: Large Dimensions and String Physics in Future Colliders

abstract:
  We review the status of low-scale string theories and large extra-dimensions.
After an overview on different string realizations, we discuss some of the main
important problems and we summarize present bounds on the size of possible
extra-dimensions from collider experiments.


title: Phenomenology of Maximal and Near-Maximal Lepton Mixing

abstract:
  We study the phenomenological consequences of maximal and near-maximal mixing
of the electron neutrino with other ($x$=tau and/or muon) neutrinos. We
describe the deviations from maximal mixing in terms of a parameter
$\epsilon\equiv1-2\sin^2\theta_{ex}$ and quantify the present experimental
status for $|\epsilon|<0.3$. We find that the global analysis of solar neutrino
data allows maximal mixing with confidence level better than 99% for $10^{-8}$
eV$^2\lsim\Delta m^2\lsim2\times10^{-7}$ eV$^2$. In the mass ranges $\Delta
m^2\gsim 1.5\times10^{-5}$ eV$^2$ and $4\times10^{-10}$ eV$^2\lsim\Delta
m^2\lsim2\times10^{-7}$ eV$^2$ the full interval $|\epsilon|<0.3$ is allowed
within 4$\sigma$(99.995 % CL). We suggest ways to measure $\epsilon$ in future
experiments. The observable that is most sensitive to $\epsilon$ is the rate
[NC]/[CC] in combination with the Day-Night asymmetry in the SNO detector. With
theoretical and statistical uncertainties, the expected accuracy after 5 years
is $\Delta \epsilon\sim 0.07$. We also discuss the effects of maximal and
near-maximal $\nu_e$-mixing in atmospheric neutrinos, supernova neutrinos, and
neutrinoless double beta decay.


title: Resonant Slepton Production in Hadron-Hadron Collisions

abstract:
  We consider the resonant production of sleptons via R-parity violation in
hadron-hadron collisions followed by supersymmetric gauge decays of the
sleptons. We look at decay modes which lead to the production of a like-sign
dilepton pair. The dominant production mechanism giving this signature is the
resonant production of a charged slepton followed by a decay to a charged
lepton and a neutralino which then decays via R-parity violation. The discovery
potential of this process at Run II of the Tevatron and the LHC is investigated
using the HERWIG Monte Carlo event generator. We include the backgrounds from
the MSSM. We conclude with a discussion of the possibility of extracting the
lightest neutralino and slepton masses.


title:
Baryon Transport in Dual Models and the Possibility of a Backward Peak
  in Diffraction

abstract:
  We begin to briefly survey the experimental and conceptual side of baryon
transfers in particle scattering. A discussion of baryon transfers in heavy ion
scattering follows. It shortly reviews existing string model concepts, which
were found to be consistent with the data. With this motivation we turn to a
more careful consideration of the relevant topological structures. The baryon
transfer is associated with one of two possible cuts in baryonium exchange.
  From the color structure the baryonium can be identified with an Odderon
exchange. We conjecture that the two Odderon cuts occur with an opposite sign
and partially cancel. As the Odderon is predicted to have a rather high
trajectory it has to involve small coupling constants. As this suppression is
not anticipated for diffractive processes a tiny observable backward peak is
argued to occur in the initial baryon distribution in massive diffractive
systems.


title: Signatures of the Light Down-Squark Scenario at the Upgraded Tevatron

abstract:
  In scenarios with relatively light down squarks, motivated, e.g., by SO(10) D
terms, jets + missing $E_T$ signals can be observed at the luminosity upgraded
Tevatron even if the squarks are much heavier than the gluinos and the common
gaugino mass ($M_{{1/2}}$) at $M_G$ lies above the LEP allowed lower bound. In
the conventional mSUGRA model with heavy squarks practically no signal is
expected in this channel. The possiblity of distinguishing between various
SUGRA motivated scenarios by exploiting the missing $E_T$ and jet $p_T$
distributions, opposite sign dileptons + jets + missing $E_T$ events and clean
trilepton signals have been discussed.


title: Nonperturbative Calculation of Scattering Amplitudes

abstract:
  A method for the nonperturbative calculation of scattering amplitudes and
cross sections is discussed in the context of light-cone quantization. The
Lanczos-based recursion method of Haydock is suggested for the computation of
matrix elements of the resolvent for the light-cone Hamiltonian, from which the
T-matrix can be constructed. The scattering of composite particles is handled
by a generalization of a formulation given by Wick.


title: Real and Virtual Compton Scattering off the Nucleon

abstract:
  A review is given of the very recent developments in the fields of real and
virtual Compton scattering off the nucleon. Both real and virtual Compton
scattering reactions are discussed at low outgoing photon energy where one
accesses polarizabilities of the nucleon. The real Compton scattering at large
momentum transfer is discussed which is asymptotically a tool to obtain
information on the valence quark wave function of the nucleon. The rapid
developments in deeply virtual Compton scattering and associated meson
electroproduction reactions at high energy, high photon virtuality and small
momentum transfer to the nucleon are discussed. A unified theoretical
description of those processes has emerged over the last few years, which gives
access to new, generalized parton distributions. The experimental status and
perspectives in these fields are also discussed.


title:
Quark Mass Matrices with Four and Five Texture Zeroes, and the CKM
  Matrix, in terms of Mass Eigenvalues

abstract:
  Using the triangular matrix techniques of Kuo et al and Chiu et al for the
four and five texture zero cases, with vanishing (11) elements for U and D
matrices, it is shown, from the general eigenvalue equations and hierarchy
conditions, that the quark mass matrices, and the CKM matrix can be expressed
(except for the phases) entirely in terms of quark masses. The matrix
structures are then quite simple and transparent. We confirm their results for
the five texture zero case but find, upon closer examination of all the CKM
elements which our results provide, that six of their nine patterns for the
four texture zero case are not compatible with experiments. In total, only one
five-texture zero and three four-texture zero patterns are allowed.


title: Prompt muon contribution to the flux underwater

abstract:
  We present high energy spectra and zenith-angle distributions of the
atmospheric muons computed for the depths of the locations of the underwater
neutrino telescopes. We compare the calculations with the data obtained in the
Baikal and the AMANDA muon experiments. The prompt muon contribution to the
muon flux underwater due to recent perturbative QCD-based models of the charm
production is expected to be observable at depths of the large underwater
neutrino telescopes. This appears to be probable even at rather shallow depths
(1-2 km), provided that the energy threshold for muon detection is raised above
$\sim 100$ TeV.


title: Runing of Axial Coupling Constant

abstract:
  We illustrate that both of massless pseudoscalar meson fields and
constitutent quark fields are dynamical field degrees of freedom in energy
region between chiral symmetry spontaneously broken scale and quark confinement
scale. This physical configuration yields a renormalization running axial
coupling constant $g_{_A}(\mu)$. The one-loop renormalization prediction
$g_{_A}(\mu=m_{_N})=0.75$ and $g_{_A}(\mu=m_\pi)=0.96$ agree with $\beta$ decay
of neutron and $\pi^0\to\gamma\gamma$ respectively. We also calculate
$\rho^\pm\to\gamma\pi$ and $\omega\to\gamma\pi$ decays up to the next to
leading order of $N_c^{-1}$ expansion and including all order effects of vector
meson momentum expansion. The results strongly support prediction of
renormalization running, $g_{_A}(\mu=m_\rho)=0.77$.


title: Hyperon Enhancement in the Dual Parton Model

abstract:
  We review the two sources of hyperon enhancement in the dual parton model:
strings originating from diquark-antidiquark pairs in the nucleon sea and net
baryons containing two or three sea quarks with a yield controlled by the
observed stopping. We show that adding final state interactions (including
strangeness exchange reactions as well as the inverse reactions required by
detailed balance) with a single averaged cross-section $\sigma=0.2$ mb, we can
explain the observed hyperon enhancement in PbPb collisions at CERN SPS.


title:
Graphical Representation of CP Violation Effects in Neutrinoless Double
  Beta Decay

abstract:
  We illustrate the graphical method that gives the constraints on the
parameters appearing in the neutrino oscillation experiments and the
neutrinoless double beta decay. This method is applicable in three and four
generations. Though this method is valid for more general case, we examine
explicitly the cases in which the CP violating factors take $\pm 1$ or $\pm i$
in the neutrinoless double beta decay for illustrative clearance. We also
discuss some mass matrix models which lead to the above CP violating factors.


title:
Comparison of $k_T$-Factorization Approach and QCD Parton Model for
  Charm and Beauty Hadroproduction

abstract:
  We compare the numerical predictions for heavy quark production in high
energy hadron collisions of the conventional QCD parton model and the
$k_T$-factorization approach (semihard theory). The total production cross
sections, one-particle rapidity and $p_T$ distributions as well as two-particle
correlations are considered. The difference in the predictions of the two
approaches is not very large, while the shapes of the distributions are
slightly different.


title: The Angular Momentum and g_1^p Sum Rules for the Proton

abstract:
  The gauge invariant operator formulation of the angular momentum sum rule
${1\over2} = J_q + J_g$ for the proton is presented and contrasted with the sum
rule for the first moment of the polarised structure function $g_1^p$. The
decoupling of the axial charge $a^0$ from the angular momentum sum rule is
highlighted and the possible QCD field-theoretic basis for an angular momentum
sum rule of the form ${1\over2} = {1\over2}\D q + \D g + L_q + L_g$ is
critically discussed.


title: On factorisation at small x

abstract:
  We investigate factorisation at small x using a variety of analytical and
numerical techniques. Previous results on factorisation in collinear models are
generalised to the case of the full BFKL equation, and illustrated in the
example of a collinear model which includes higher twist terms. Unlike the
simplest collinear model, the BFKL equation leads to effective anomalous
dimensions containing higher-twist pieces which grow as a (non-perturbative)
power at small x. While these pieces dominate the effective splitting function
at very small x they do not lead to a break-down of factorisation insofar as
their effect on the predicted scaling violations remains strongly suppressed.


title: On the forward-backward correlations in a two-stage scenario

abstract:
  It is demonstrated that in a two-stage scenario with elementary Poissonian
emitters of particles (colour strings) arbitrarily distributed in their number
and average multiplicities, the forward- backward correlations are completely
determined by the final distribution of the forward particles. The observed
linear form of the correlations then necessarily requires this distribution to
have a negative binomial form. For emitters with a negative binomial
distribution of the produced particles distributed so as to give the final
distribution also of a negative binomial form, the forward-backward
correlations have an essentially non-linear form, which disagrees with the
experimental data.


title:
Large CP violation in radiative B decays in supersymmetry without
  R-parity

abstract:
  We demonstrate that the R-parity breaking interactions within their current
experimental upper bounds can give rise to large mixing-induced CP asymmetry in
exclusive radiative B decays that may be detectable in the upcoming B
factories.


title: Inverted Hierarchy Models of Neutrino Masses

abstract:
  We study models of neutrino masses which naturally give rise to an inverted
mass hierarchy and bi-maximal mixing. The models are based on the see-saw
mechanism with three right-handed neutrinos, which generates a single mass term
of the form $\nu_e(\nu_{\mu}+\nu_{\tau})$ corresponding to two degenerate
neutrinos $\nu_e$ and $\nu_{\mu}+\nu_{\tau}$, and one massless neutrino
$\nu_{\mu}-\nu_{\tau}$. Atmospheric neutrino oscillations are accounted for if
the degenerate mass term is about $5\times 10^{-2}$ eV. Solar neutrino
oscillations of the Large Mixing Angle MSW type arise when small perturbations
are included leading to a mass splitting between the degenerate pair of about
$(1.7-2.0)\times 10^{-4}$ eV for the successful cases. We study the conditions
that such models must satisfy in the framework of a U(1) family symmetry broken
by vector singlets, and catalogue the simplest examples. We then perform a
renormalisation group analysis of the neutrino masses and mixing angles,
assuming the supersymmetric standard model, and find modest radiative
corrections of a few per cent, showing that the model is stable. At low
energies we find $\sin^22\theta_{23}\approx 0.93-0.96$ and
$\sin^22\theta_{12}\approx 0.9-1.0$.


title: Dynamics of the chiral phase transition at finite chemical potential

abstract:
  We study the dynamics of the chiral phase transition at finite chemical
potential in the Gross-Neveu model in the leading order in large-N
approximation. We consider evolutions starting in local thermal equilibrium in
the massless unbroken phase for conditions pertaining to traversing a first or
second order phase transition. We assume boost invariant kinematics and
determine the evolution of the the order parameter $\sigma$, the energy density
and pressure as well as the effective temperature, chemical potential and
interpolating number densities as a function of $\tau$.


title: Electroweak Precision Physics at e+ e- Colliders with RacoonWW

abstract:
  We present precise predictions for the processes e+ e- -> WW -> 4f(gamma) at
LEP2 and future Linear-Collider (LC) energies obtained with the Monte Carlo
generator RacoonWW. The program RacoonWW includes the complete O(alpha)
electroweak radiative corrections to e+ e- -> WW -> 4f in the double-pole
approximation (DPA). While the virtual corrections are treated in DPA, the
calculation of the bremsstrahlung corrections is based on the full lowest-order
matrix elements to the processes e+ e- -> 4f+gamma. This asymmetric treatment
of virtual and real photons requires a careful matching of the arising infrared
and collinear singularities. We also take into account higher-order
initial-state photon radiation via the structure-function method. Here, we
briefly describe the RacoonWW approach, give numerical results for the total
W-pair production cross sections, confront them with LEP2 data, and study the
impact of the radiative corrections on angular and W-invariant-mass
distributions at LEP2 and LC energies.


title: Neutrinos produced by ultrahigh-energy photons at high red shift

abstract:
  Some of the proposed explanations for the origin of ultrahigh-energy cosmic
rays invoke new sources of energetic photons (e.g., topological defects, relic
particles, etc.). At high red shift, when the cosmic microwave background has a
higher temperature but the radio background is low, the ultrahigh-energy
photons can generate neutrinos through pair-production of muons and pions.
Neutrinos produced at high red shift by slowly evolving sources can be
detected. Rapidly evolving sources of photons can be ruled out based on the
existing upper limit on the neutrino flux.


title:
Simple predictions from ALCOR_c for rehadronisation of charmed quark
  matter

abstract:
  We study the production of charmed hadrons with the help of ALCOR_c, the
algebraic coalescence model for rehadronisation of charmed quark matter.
Mesonic ratios are introduced as factors connecting various antibaryon to
baryon ratios. The resulting simple relations could serve as tests of quark
matter formation and coalescence type rehadronization in heavy ion collisions.


title:
Measurements of the $Q^2$-Dependence of the Proton and Neutron Spin
  Structure Functions g1p and g1n

abstract:
  The structure functions g1p and g1n have been measured over the range 0.014 <
x < 0.9 and 1 < Q2 < 40 GeV2 using deep-inelastic scattering of 48 GeV
longitudinally polarized electrons from polarized protons and deuterons. We
find that the Q2 dependence of g1p (g1n) at fixed x is very similar to that of
the spin-averaged structure function F1p (F1n). From a NLO QCD fit to all
available data we find $\Gamma_1^p - \Gamma_1^n =0.176 \pm 0.003 \pm 0.007$ at
Q2=5 GeV2, in agreement with the Bjorken sum rule prediction of 0.182 \pm
0.005.


title:
Comment on ``Linking solar and long baseline terrestrial neutrino
  experiments''

abstract:
  We comment on ``Linking solar and long baseline terrestrial neutrino
experiments''


title:
Vacuum properties in the presence of quantum fluctuations of the quark
  condensate

abstract:
  The quantum fluctuations of the quark condensate are calculated using a
regulated Nambu Jona-Lasinio model. The corresponding quantum fluctuations of
the chiral fields are compared to those which are predicted by an
''equivalent'' sigma model. They are found to be large and comparable in size
but they do not restore chiral symmetry. The restoration of chiral symmetry is
prevented by an ''exchange term'' of the pion field which does not appear in
the equivalent sigma model. A vacuum instability is found to be dangerously
close when the model is regulated with a sharp 4-momentum cut-off.


title:
O(alpha_s^5 m) quarkonium 1S spectrum in large-beta_0 approximation and
  renormalon cancellation

abstract:
  Presently the quarkonium spectrum, written in terms of the quark MSbar-mass,
is known at O(alpha_s^3 m) accuracy. We point out that in order to achieve
O(alpha_s^4 m) accuracy it is sufficient to calculate further (I) the
O(alpha_s^4 m) relation between the MSbar-mass and the pole-mass, and (II) the
binding energy at O(alpha_s^5 m) in the large-beta_0 approximation. We
calculate the latter correction analytically for the 1S-state and study its
phenomenological implications.


title: Study of $B_{s,d}\to l^+l^-\gamma$ Decays

abstract:
  We study the decays of $B_{s,d} \to l^+ l^- \gamma (l=e, \mu,\tau)$ within
the light-front model. We calculate the tensor type form factors and use these
form factors to evaluate the decay branching ratios. We find that, in the
standard model, the branching ratios of $B_{s(d)} \to \l^+ \l^- \gamma$ ($\l=e,
\mu,\tau$) are $7.1\times 10^{-9}$ ($1.5\times 10^{-10}$), $8.3\times 10^{-9}$
($1.8\times 10^{-10}$), $1.6\times 10^{-8}$ ($6.2\times 10^{-10}$),
respectively.


title: R-mediation of Dynamical Supersymmetry Breaking

abstract:
  We propose a simple scenario of the dynamical supersymmetry breaking in four
dimensional supergravity theories. The supersymmetry breaking sector is assumed
to be completely separated as a sequestered sector from the visible sector,
except for the communication by the gravity and U(1)_R gauge interactions, and
the supersymmetry breaking is mediated by the superconformal anomaly and U(1)_R
gauge interaction. Supersymmetry is dynamically broken by the interplay between
the non-perturbative effect of the gauge interaction and Fayet-Iliopoulos
D-term of U(1)_R which necessarily exists in supergravity theories with gauged
U(1)_R symmetry. We construct an explicit model which gives phenomenologically
acceptable mass spectrum of superpartners with vanishing (or very small)
cosmological constant.


title: From Minimal to Realistic Supersymmetric SU(5) Grand Unification

abstract:
  We construct and discuss a "realistic" example of SUSY SU(5) GUT model, with
an additional U(1) flavour symmetry, that is not plagued by the need of large
fine tunings, like those associated with doublet-triplet splitting in the
minimal model, and that leads to an acceptable phenomenology. This includes
coupling unification with a value of alpha_s(m_Z) in much better agreement with
the data than in the minimal version, an acceptable hierarchical pattern for
fermion masses and mixing angles, also including neutrino masses and mixings,
and a proton decay rate compatible with present limits (but the discovery of
proton decay should be within reach of the next generation of experiments). In
the neutrino sector the preferred solution is one with nearly maximal mixing
both for atmospheric and solar neutrinos.


title: Two-mixing texture for three active neutrinos

abstract:
  The conjecture that among three massive neutrinos $\nu_1, \nu_2, \nu_3$ there
is no direct mixing between $\nu_1$ and $\nu_3$ leads to a two-mixing texture
for three active neutrinos $\nu_e, \nu_\mu, \nu_\tau$. This texture, much
discussed previously, is neatly consistent with the observed deficits of solar
$\nu_e$'s and atmospheric $\nu_\mu$'s, but (without extra mixing with at least
one sterile neutrino $\nu_s$) predicts no LSND effect for accelerator
$\nu_\mu$'s. In this option, the masses $m^2_1\stackrel{<}{\sim} m^2_2 <<
m^2_3$ are readily estimated. The characteristic feature of the two-mixing
neutrino texture that {\it only the close neighbours in the hierarchy of
massive neutrinos $\nu_1, \nu_2, \nu_3$ mix significantly} may be physically
meaningful. Going out from the notion of mixing matrix we construct an
intrinsic occupation-number operator whose {\it eigenvalues} 0, 1, 2 {\it
numerate the three generations of massive neutrinos}. Analogical constructions
work also for charged leptons as well as for up and down quarks.


title: QCD factorization for $B\to\pi K$ decays

abstract:
  We examine some consequences of the QCD factorization approach to
non-leptonic B decays into $\pi K$ and $\pi \pi$ final states, including a set
of enhanced power corrections. Among the robust predictions of the approach we
find small strong-interaction phases (with one notable exception) and a pattern
of CP-averaged branching fractions, which in some cases differ significantly
from the current central values reported by the CLEO Collaboration.


title: Colour Dipoles and Saturation

abstract:
  We employ values of the colour dipole cross section extracted from
electroproduction and photoproduction data to show that gluon saturation
effects are not required by the current HERA data but will become important in
the THERA energy region.


title: Higher twists and maxima for DIS on nuclei in high density QCD region

abstract:
  We show that the ratio of different structure functions have a maximum which
depends on $x_B$ and $A$. We argue that these maxima are proportional to the
saturation scale. The analysis of leading and higher twist contributions for
different observables is given with the aim of determining the kinematic region
where high parton density effects could be seen experimentally.


title: Electroweak effects in radiative B decays

abstract:
  We compute the two-loop electroweak corrections to the radiative decays of
the B meson in the SM. Electroweak effects reduce the Wilson coefficient
C_7^eff(mw) by 2.6% for a light Higgs boson of about 100 GeV and are less
important for a heavier Higgs. The leading term of a heavy top expansion of our
result differs from the one obtained in the gaugeless approximation where only
top quark Yukawa couplings are considered: we discuss the origin of the
discrepancy and provide a criterion for the validity of the gaugeless
approximation. As a byproduct of the calculation we also obtain the O(alpha)
corrections to the Wilson coefficient of the four-fermion operator Q_2. A
careful analysis of the interplay between electroweak and QCD effects leads to
an overall 2% reduction of the total branching ratio for B -> X_s gamma due to
purely electroweak corrections. For a light Higgs boson, the up-to-date SM
prediction is BR_gamma=3.29 10^-4.


title:
On Radiative $\phi \to \eta \gamma$, $\phi \to \eta^\prime \gamma$
  Decays

abstract:
  We use QCD sum-rules to study the decays $\phi \to \eta \gamma$ and $\phi \to
\eta^\prime \gamma$, obtaining ${\cal B}(\phi \to \eta \gamma)=(1.15 \pm 0.2)
10^{-2}$ and ${\cal B}(\phi \to \eta^\prime \gamma)=(1.18 \pm 0.4) 10^{-4}$, in
very good agreement with existing experimental data. We also discuss the issue
of $\eta-\eta^\prime$ mixing, predicting the $\eta$ and $\eta^\prime$ decay
constants in a mixing scheme in the quark-flavour basis.


title:
Energy Dependence of \sigma^{DD}/\sigma_{tot} in DIS and Shadowing
  Corrections

abstract:
  We gereralize the Kochegov-McLerran formula for the ratio
$\sigma^{DD}/\sigma_{tot}$ in perturbative QCD, using Mueller-Glauber approach
for shadowing corrections and AGK cutting rules. We investigate several
phenomenological approaches with the goal of obtaining results consisent with
experimental data. We fail to reproduce the observed weak energy dependence of
the ratio, and conclude that the soft nonperturbative contribution present at
short distances must also be included.


title: Comment on Equal Velocity Assumption for Neutrino Oscillations

abstract:
  The so-called equal velocity prescription for neutrino oscillations is
forbidden kinematically.


title:
Form Factors for Semileptonic B -> pi and D -> pi Decays from the Omnes
  Representation

abstract:
  We use the Omnes representation to obtain the q-squared dependence of the
form factors f+ and f0 for semileptonic H -> pi decays from the elastic pi H ->
pi H scattering amplitudes, where H denotes a B or D meson. The scattering
amplitudes used satisfy elastic unitarity and are calculated from two-particle
irreducible amplitudes obtained using tree-level heavy meson chiral
perturbation theory (HMChPT). The q-squared dependences for the form factors
agree with lattice QCD results when the HMChPT coupling constant, g, takes
values smaller than 0.32, and confirm the milder dependence of f0 on q-squared
found in sumrule calculations.


title:
High Energy Nucleus-Nucleus Collisions In View Of The Multi-Peripheral
  Model

abstract:
  The hypothesis of the multi peripheral model is extended to the
hadron-nucleus interactions and then generalized to the nucleus-nucleus case.
The processing of the model depends on input parameters that are extracted from
the features of the experiments in this field. The number of encountered
nucleons from both target and projectile are estimated according to the eikonal
scattering approach. The screening effect due to the interaction of the
projectile nucleons in successive manner with the target nucleus is considered.
The rapidity distributions of fast particles are reproduced for the successive
collisions in p-S and $^{32}$S-$^{32}$S interactions at 200 A GeV. A global
fair agreement is found in comparison with data of the experiment SLAC-NA-035.


title: The `LEP paradox'

abstract:
  Is there a Higgs? Where is it? Is supersymmetry there? Where is it? By
discussing these questions, we call attention to the `LEP paradox', which is
how we see the naturalness problem of the Fermi scale after a decade of
electroweak precision measurements, mostly done at LEP.


title:
Bilinear R-parity Violation and Small Neutrino Masses: a Self-consistent
  Framework

abstract:
  We study extensions of supersymmetric models without R-parity which include
an anomalous U(1)_H horizontal symmetry. Bilinear R-parity violating terms
induce a neutrino mass at tree level of approximately $(\theta^2)^\delta$ eV
where $\theta\approx 0.22$ is the U(1)_H breaking parameter and $\delta$ is an
integer number that depends on the horizontal charges of the leptons. For
$\delta=1$ a unique self-consistent model arises in which i) all the
superpotential trilinear R-parity violating couplings are forbidden by
holomorphy; ii) the tree level neutrino mass falls in the range suggested by
the atmospheric neutrino problem; iii) radiative contributions to neutrino
masses are strongly suppressed resulting in a squared solar mass difference of
few 10^{-8} eV^2 which only allows for the LOW (or quasi-vacuum) solution to
the solar neutrino problem; iv) the neutrino mixing angles are not suppressed
by powers of $\theta$ and can naturally be large.


title: Collider signals of brane fluctuations

abstract:
  Assuming that we live on a non rigid brane with TeV-scale tension, the scalar
fields that control the coordinates of our brane in the extra dimensions give
rise to missing energy signals at high-energy colliders with a characteristic
angular and energy spectrum, identical to the one due to graviton emission in 6
extra dimensions. LEP bounds and LHC capabilities are analyzed.


title: Effects of Higher-Order Threshold Corrections in High-E_T Jet Production

abstract:
  Results for higher-order threshold enhancements in high-E_T jet production in
hadron-hadron collisions are presented. Expressions are given for the
next-to-next-to-leading order (NNLO) threshold corrections to the single-jet
inclusive cross section at next-to-leading logarithmic (NLL) accuracy. The
corrections are found to be small for the specific choice of E_T/2 for the
factorization and renormalization scales, and the corrected cross section shows
a substantial reduction of the scale dependence. A comparison to experimental
results from the Tevatron is presented.


title: Interesting consequences of brane cosmology

abstract:
  We discuss cosmology in four dimensions within a context of brane-world
scenario.Such models can predict chaotic inflation with very low reheat
temperature depending on the brane tension. We notice that the gravitino
abundance is different in the brane-world cosmology and by tuning the brane
tension it is possible to get extremely low abundance. We also study
Affleck-Dine baryogenesis in our toy model.


title:
Three Generation Long-wavelength Vacuum Oscillation Solution to the
  Solar Neutrino Problem

abstract:
  We investigate the current status of the long-wavelength vacuum oscillation
solution to the solar neutrino problem and to what extent the presence of a
third neutrino can affect and modify it. Assuming that the smaller mass squared
difference that can induce such oscillations, $\Delta m^2_{12}$, is in the
range $10^{-11}-10^{-8}$ eV$^2$ and the larger one, $\Delta m^2_{23}$, in the
range relevant to atmospheric neutrino observations, we analyze the most recent
solar neutrino data coming from Homestake, SAGE, GALLEX, GNO and
Super-Kamiokande experiments in the context of three neutrino generations. We
include in our vacuum oscillation analysis the MSW effect in the Sun, which is
relevant for some of the parameter space scrutinized. We have also performed,
as an extreme exercise, the fit without Homestake data. % While we found that
the MSW effect basically does not affect the best fitted parameters, it
significantly modifies the allowed parameter space for $\Delta m^2_{12}$ larger
than $\sim 3 \times 10^{-10}$ eV$^2$, in good agreement with the result
obtained by A. Friedland in the case of two generations. % Although the
presence of a third neutrino does not essentially improve the quality of the
fit, the solar neutrino data alone can give an upper bound on $\theta_{13}$,
which is constrained to be less than $\sim 60^\circ$ at 95 % C.L.


title: Strange quarks, magnetic moments and SU(3)

abstract:
  We discuss the agreement in sign between the recently measured strange
contribution to the proton magnetic moment and SU(3) based fits to baryon octet
magnetic moments.


title:
Estimate of a Chiral-Odd Contribution to Single Transverse-Spin
  Asymmetry in Hadronic Pion Production

abstract:
  We present an estimate of a chiral-odd contribution to the single
transverse-spin asymmetry in the large-$p_T$ pion production in the
nucleon-nucleon collision. In this contribution the transversity distribution
and the chiral-odd spin-independent twist-3 distribution appear. Because of the
smallness of the corresponding hard cross section, this term turned out to be
negligible in all kinematic regions compared with the chiral-even contribution.


title:
Uncertainty of Predicted High Q2 Structure Functions due to
  Parametrization Assumptions

abstract:
  The HERA luminosity upgrade is expected to provide statistically significant
measurements of the proton structure functions at 0.5<x<0.7 and very high Q2
(Q2>>M_{Z}^2). The behaviour of the parton densities (PDFs) in this high x, Q2
regime is predicted from DGLAP evolution of PDF parametrizations from lower Q2
fits of the data. Uncertainties in the PDFs at high x may propagate to lower x
through DGLAP evolution at very high Q2. In this presentation the behaviour of
the PDFs at high x is reexamined with different parametrizations that have been
tried earlier, and with somewhat different constraints, set primarily by
existing fixed target data. We present and discuss the effects at Q2=40000GeV^2
and compare our results with uncertainties obtained from propagation of
experimental errors at high x, high Q2 DIS data.


title: Screening corrections in DIS at low Q^2 and x

abstract:
  In this investigation we present a detailed study of $\partial F_2/\partial
\ln Q^2$ which is supported by a coupled analysis of $J/\Psi$ photo and DIS
production. Both channels are directly proportional to $xG(x,Q^2)$, and as such
serve as excellent discriminators between different approaches and models.
  We then show that taking GRV98NLO as input and correcting it for SC, we can
reproduce the recent HERA data well. The calculation depends on one parameter
$R^2=8.5GeV^{-2}$ which is directly determined from the $J/\Psi$
photoproduction forward differential slope. With this input we obtain an
excellent fit to the $J/\Psi$ photo and DIS production data. Our calculations
made in the LLA of pQCD take into account the corrections implied by the real
part of the production amplitude, off diagonal (skewed) gluon distributions and
the Fermi motion of the charm quarks within the bound Charmonium system.


title: The Lightest Strange Scalar Resonance

abstract:
  I present the results of a recent calculation to determine the number of
strange scalar resonances below 1.8 GeV based on the analytic properties of the
experimental pi K scattering amplitude. Only one resonance was found in the
data, and this is readily identifiable as the K_0^*(1430). We found no evidence
to support the kappa(900).


title:
Measuring MSSM CP-violating Phases through Spin Correlated
  Supersymmetric Tri-lepton Signatures at the Tevatron

abstract:
  We provide a detailed analysis of the supersymmetric tri-lepton signals for
sparticle searches at the Tevatron in the minimal supersymmetric standard model
with general CP-violating phases but without flavor mixing among sfermions of
different generation. The stringent experimental constraints on the
CP-violating phases from the electron and neutron electric dipole moments are
included in the analysis for two exemplary scenarios of the SUSY parameters;
one with decoupled first two generation sfermions and the other with
non-decoupled sfermions. In both scenarios, the production cross section and
the branching fractions of the leptonic chargino and neutralino decays are
sensitive to CP-violating phases. The production-decay spin correlations lead
to several non-trivial CP-even observables such as the lepton invariant mass
distribution and the lepton angular distribution, and several interesting T-odd
(CP-odd) momentum triple products. The possibility of measuring the
CP-violating phases directly through those T-odd observables is investigated in
detail.


title:
Skewed parton distributions and the scale dependence of the transverse
  size parameter

abstract:
  We discuss the scale dependence of a skewed parton distribution of the pion
obtained from a generalized light-cone wave function overlap formula. Using a
simple ansatz for the transverse momentum dependence of the light-cone wave
function and restricting ourselves to the case of a zero skewedness parameter,
the skewed parton distribution can be expressed through an ordinary parton
distribution multiplied by an exponential function. Matching the generalized
and ordinary DGLAP evolution equations of the skewed and ordinary parton
distributions, respectively, we derive a constraint for the scale dependence of
the transverse size parameter, which describes the width of the pion wave
function in transverse momentum space. This constraint has implications for the
Fock state probability and valence distribution. We apply our results to the
pion form factor.


title: Precise Physics of Simple Atoms

abstract:
  We give a review of experimental and theoretical results on the precision
study of hydrogen-like atoms with low value of the nuclear charge Z.


title: Higher Twist Distribution Amplitudes of the Nucleon in QCD

abstract:
  We present the first systematic study of higher-twist light-cone distribution
amplitudes of the nucleon in QCD. We find that the valence three-quark state is
described at small transverse separations by eight independent distribution
amplitudes. One of them is leading twist-3, three distributions are twist-4 and
twist-5, respectively, and one is twist-6. A complete set of distribution
amplitudes is constructed, which satisfies equations of motion and constraints
that follow from conformal expansion. Nonperturbative input parameters are
estimated from QCD sum rules.


title: Probing R-violating top quark decays at hadron colliders

abstract:
  We examine the possibility of observing exotic top quark decays via
R-violating SUSY interactions at the Fermilab Tevatron and CERN LHC. We present
cross-sections for $t\bar t$ production followed by the subsequent decay of
either $t$ or $\bar t$ via the R-violating interaction while the other
undergoes the SM decay. With suitable kinematic cuts, we find that the exotic
decays can possibly be detected over standard model backgrounds at the future
runs of the Tevatron and LHC, but not at Run 1 of the Tevatron due to limited
statistics. Discovery limits for R-Violating couplings in the top sector are
presented.


title: Summary of Golden Measurements at a $\nu$-Factory

abstract:
  The precision and discovery potential of a neutrino factory based on muon
storage rings is summarized. For three-family neutrino oscillations, we analyze
how to measure or severely constraint the angle $\theta_{13}$, CP violation,
MSW effects and the sign of the atmospheric mass difference $\Delta m^2_{23}$.
The appearance of ``wrong-sign muons'' at three reference baselines is
considered: 732 km, 3500 km and 7332 km. We exploit the dependence of the
signal on the neutrino energy, and include as well realistic background
estimations and detection efficiencies. The optimal baseline turns out to be
$O$(3000 km).


title: Physics at high Q^2 and p^2_t: Summary of DIS 2000

abstract:
  We summarize the experimental and theoretical results presented in the
"Physics at the Highest Q^2 and p^2_t" working group at the DIS 2000 Workshop.
High Q^2 and p^2_t processes measured at current and future colliders allow to
improve our knowledge of Standard Model (SM) physics, by providing precise
measurements of the SM parameters and, consequently, consistency checks of the
SM. Moreover, they give information on key quantities for the calculation of
the SM expectations in a yet unexplored domain, such as the parton densities of
the proton or the photon. In addition to these experimental inputs,
higher-order calculations are also needed to obtain precise expectations for SM
processes, which are a key ingredient for the searches for new phenomena in
high Q^2 and p^2_t processes at current and future experiments. The
experimental and theoretical status of SM physics at high Q^2 and p^2_t is
reviewed in the first part of this summary, with the remaining being dedicated
to physics beyond the Standard Model.


title: Update on four-family neutrino oscillations at Neutrino Factory

abstract:
  The prospects of measuring the leptonic angles and CP-odd phases at a {\em
neutrino factory} are discussed in the scenario of three active plus one
sterile neutrino, motivated by the $\nu_\mu \raw \nu_e$ LSND signal.
Sensitivity to the MNS mixing matrix angles at $O (10^{-3})$ is achieved with a
1 T detector at $\sim 1$ km from the source, whereas leptonic CP-violation can
be measured through tau detection with a 1 kT detector at $\sim 100$ km.


title: The 2+1 Dimensional NJL Model at Finite Temperature

abstract:
  We decribe properties of 2+1-dimensional Nambu-Jona-Lasinio (NJL) models at
finite-temperature, beginning with the model with a discrete chiral symmetry.
We then consider the model with a continuous $U(1) \times U(1)$ chiral
symmetry, describing the restoration of the symmetry at finite temperature. In
each case, we compute the free energy and comment on a recently proposed
constraint based upon it. We conclude with a brief discussion of NJL models
with larger chiral symmetries.


title: CP violation in gauge theories

abstract:
  We define the CP transformation properties of scalars, fermions and vectors
in a gauge theory and show that only three types of interactions can lead to CP
violation: scalar interactions, fermion-scalar interactions and $ F \tilde F $
associated with the strong CP problem and which involve only the gauge fields.
For technicolor theories this implies the absence of CP violation within
perturbation theory.


title:
Finding Z' bosons coupled preferentially to the third family at CERN LEP
  and the Fermilab Tevatron

abstract:
  Z' bosons that couple preferentially to the third generation fermions can
arise in models with extended weak (SU(2)xSU(2)) or hypercharge (U(1)xU(1))
gauge groups. We show that existing limits on quark-lepton compositeness set by
the LEP and Tevatron experiments translate into lower bounds of order a few
hundred GeV on the masses of these Z' bosons. Resonances of this mass can be
directly produced at the Tevatron. Accordingly, we explore in detail the limits
that can be set at Run II using the process p pbar -> Z' -> tau tau -> e mu. We
also comment on the possibility of using hadronically-decaying taus to improve
the limits.


title:
Theoretical Challenges for a Precision Measurement of the W Mass at
  Hadron Colliders

abstract:
  We discuss the O(alpha) electroweak radiative corrections to W and Z boson
production and their impact on the measurement of the W mass at hadron
colliders. The results of recent improved calculations are presented. We also
briefly discuss the O(alpha) corrections to Drell-Yan production in the high
invariant mass region.


title: Single superpartner production at Tevatron Run II

abstract:
  We study the single productions of supersymmetric particles at Tevatron Run
II which occur in the $2 \to 2-body$ processes involving R-parity violating
couplings of type $\l'_{ijk} L_i Q_j D_k^c$. We focus on the single gaugino
productions which receive contributions from the resonant slepton productions.
We first calculate the amplitudes of the single gaugino productions. Then we
perform analyses of the single gaugino productions based on the three charged
leptons and like sign dilepton signatures. These analyses allow to probe
supersymmetric particles masses beyond the present experimental limits, and
many of the $\l'_{ijk}$ coupling constants down to values smaller than the
low-energy bounds. Finally, we show that the studies of the single gaugino
productions offer the opportunity to reconstruct the $\tilde \chi^0_1$, $\tilde
\chi^{\pm}_1$, $\tilde \nu_L$ and $\tilde l^{\pm}_L$ masses with a good
accuracy in a model independent way.


title: Virtual corrections to gg -> H to two loops in the heavy top limit

abstract:
  The virtual corrections to the production cross section of a Standard Model
Higgs boson are computed up to order \alpha_s^4. Using an effective Lagrangian
for the limit M_t -> \infty, we evaluate the relevant massless two-loop vertex
diagrams by mapping them onto three-loop two-point functions, following a
method recently introduced by Baikov and Smirnov. As a result, we find a
gauge-invariant contribution to the total Higgs production cross section at
NNLO.


title: Gravitational Stability and Extra Timelike Dimensions

abstract:
  Tachyonic Kaluza-Klein modes normally appear from the compactification of
extra timelike dimensions with scale $L$ and lead to some instabilities of
physical systems. We calculate the contribution of tachyonic gravitons to the
self energies of spherical massive bodies of radius $R$ and discuss their
possible gravitational stability. We find that some spherical bodies can be
stable at critical radii $R=2\pi L p$ for some positive integers $p$. We also
prove the generic property of massive bodies that for the range $0<R\leq\pi L$
the gravitational force due to the ordinary massless graviton exchange is
screened by the Kaluza-Klein mode exchange of tachyonic gravitons.


title:
The Fayet-Iliopoulos D-term and its renormalisation in softly-broken
  supersymmetric theories

abstract:
  We consider the renormalisation of the Fayet-Iliopoulos D-term in a
softly-broken abelian supersymmetric theory, and calculate the associated
beta-function through three loops. We show that there exists (at least through
three loops) a renormalisation group invariant trajectory for the coefficient
of the D-term, corresponding to the conformal anomaly solution for the soft
masses and couplings.


title: Polarized J/psi from chi_{cJ} and psi' Decays at the Tevatron

abstract:
  We calculate the partonic cross sections for the hadroproduction of polarized
chi_{cJ} mesons using the factorization formalism of nonrelativistic QCD. We
also describe how the polarization is passed on to the J/psi mesons in the
radiative feed-down chi_{cJ} -> J/psi + gamma and in the double-cascade decays
of psi' mesons via chi_{cJ} intermediate states. These represent the missing
ingredients needed to predict the polarization of prompt J/psi mesons at the
Fermilab Tevatron.


title: Axial U(1) dynamics in eta and eta' photoproduction

abstract:
  We discuss the sensitivity of eta and eta' photoproduction near threshold to
the gluonic OZI breaking parameters in the U_A(1)-extended effective chiral
Lagrangian for low-energy QCD. Our coupled-channels analysis hints at a strong
correlation between the gluon-induced contributions to the eta' mass and the
low-energy pp -> pp eta' reaction and the near-threshold behaviour of the gamma
p -> eta p cross-section.


title:
Some higher moments of deep inelastic structure functions at
  next-to-next-to leading order of perturbative QCD

abstract:
  We present the analytic next-to-next-to-leading QCD calculation of some
higher moments of deep inelastic structure functions in the leading twist
approximation. We give results for the moments $N$=1,3,5,7,9,11,13 of the
structure function $F_3$. Similarly we present the moments $N$=10,12 for the
flavour singlet and $N$=12,14 for the non-singlet structure functions $F_2$ and
$F_L$. We have calculated both the three-loop anomalous dimensions of the
corresponding operators and the three-loop coefficient functions of the moments
of these structure functions.


title:
Vector Boson Production at Hadron Colliders: Results from HERWIG and
  Resummed Calculations

abstract:
  We discuss vector boson production at hadron colliders and the treatment of
the initial-state radiation according to Monte Carlo parton shower simulations
and resummed calculations. In particular, we investigate the effect of
matrix-element corrections to the HERWIG event generator on W/Z transverse
momentum distributions.


title: Exotic Mesons, Theory and Experiment

abstract:
  In this talk I summarize the status of exotic mesons, including both
theoretical expectations and experimental candidates. The current experimental
candidates are ``spin-parity exotics''; since these are most often considered
possible hybrid mesons, the theoretical discussion will be mainly concerned
with hybrids. The exotic meson candidates discussed are the surprisingly light
pi_1(1400) and pi_1(1600).


title:
Probing the Structure of Nucleons in the Resonance Region with CLAS at
  Jefferson Lab

abstract:
  The physics of electromagnetic excitation of nucleon resonances and of their
relevance in nucleon structure studies are discussed. Preliminary data from the
CLAS detector on the N-Delta(1232) transition multipoles, the helicity
amplitudes of the N*(1535), and the search for so-called "missing resonances"
at Jefferson Lab are presented.


title: Single Top Production as a Window to Physics Beyond the Standard Model

abstract:
  Production of single top quarks at a high energy hadron collider is studied
as a means to identify physics beyond the standard model related to the
electroweak symmetry breaking. The sensitivity of the $s$-channel $W^*$ mode,
the $t$-channel $W$-gluon fusion mode, and the \tw mode to various possible
forms of new physics is assessed, and it is found that the three modes are
sensitive to different forms of new physics, indicating that they provide
complimentary information about the properties of the top quark. Polarization
observables are also considered, and found to provide potentially useful
information about the structure of the interactions of top.


title: Gaussian Sum-Rules and Prediction of Resonance Properties

abstract:
  Techniques for using Gaussian QCD sum-rules to predict hadronic resonance
properties are developed for single-resonance and two-resonance
phenomenological models, and criteria are developed for determining which of
these models is required for analyzing a particular hadronic channel. The
vector current sum-rule coupled to the $\rho$ meson is shown to be consistent
with a single resonance model, and the Gaussian sum-rule analysis results in an
accurate $\rho$ mass prediction which exhibits excellent agreement between the
theoretical prediction of the Gaussian sum-rule and the phenomenological model.
A two-resonance model is shown to be necessary for the Gaussian sum-rule for
the non-strange quark scalar ($\bar n n$) currents. The two-resonance Gaussian
sum-rule analysis of the isoscalar and isovector ($I=0,1$) $\bar n n$ scalar
mesons exhibits excellent agreement between the theoretical prediction and
phenomenological model. The prediction of the resonance properties of the
$I=0,1$ $\bar n n$ scalar mesons in this two-resonance model provides valuable
information for the interpretation of the scalar mesons, including the X(1775).


title:
Scenario for Ultrarelativistic Nuclear Collisions: II. Geometry of
  quantum states at the earliest stage

abstract:
  We suggest that the ultrarelativistic collisions of heavy ions provide the
simplest situation for the study of strong interactions which can be understood
from first principles and without any model assumptions about the microscopic
structure of the colliding nuclei. We argue that the boost-invariant geometry
of the collision, and the existence of hard partons in the final states, both
supported by the data, make a sufficient basis for the quantum theory of the
phenomenon. We conclude that the quantum nature of the entire process is
defined by its global geometry, which is enforced by a macroscopic finite size
of the colliding objects. In this paper, we study the qualitative aspects of
the theory and review its development in two subsequent papers. Our key result
is that the effective mass of the quark in the expanding system formed in the
collision of the two nuclei is gradually built up reaching its maximum by the
time the quark mode becomes sufficiently localized. The chromo-magneto-static
interaction of the color currents flowing in the rapidity direction is the main
mechanism which is responsible for the generation of the effective mass of the
soft quark mode and therefore, for the physical scale at the earliest stage of
the collision.


title:
Scenario for Ultrarelativistic Nuclear Collisions: III. Gluons in the
  expanding geometry

abstract:
  We derive expressions for various correlators of the gauge field and find the
propagators in Hamiltonian dynamics which employs a new gauge $A^\tau=0$. This
gauge is a part of the wedge form of relativistic dynamics suggested earlier as
a tool for the study of quantum dynamics in ultra-relativistic heavy ion
collisions. We prove that the gauge is completely fixed. The gauge field is
quantized and the field of radiation and the longitudinal fields are
unambiguously separated. The new gauge puts the quark and gluon fields of the
colliding hadrons in one Hilbert space and thus allows one to avoid
factorization.


title:
Scenario for Ultrarelativistic Nuclear Collisions: IV. Effective quark
  mass at the early stage

abstract:
  Using the framework of wedge dynamics, we compute the effective transverse
mass of a soft quark mode propagating in the expanding background of hard
quarks and gluons created at the earliest time of the collision. We discover
that the wedge dynamics does not require any external infrared or collinear
cut-off. The effective mass is produced mainly due to the forward quark-quark
scattering mediated by the longitudinal (in sense of Gauss' law) magnetic
fields. Contribution of the radiation field is parametrically suppressed.


title: A Strategy for the Analysis of Semi-Inclusive Deep Inelastic Scattering

abstract:
  We present a strategy for the systematic extraction of a vast amount of
detailed information on polarized parton densities and fragmentation functions
from semi-inclusive deep inelastic scattering l+N -> l+h+X, in both LO and NLO
QCD. A method is suggested for estimating the errors involved in the much
simpler, and therefore much more attractive,
  LO analysis. The approach is based upon a novel interplay with data from
inclusive DIS and from e+e- -> hX, and leads to a much simplified form of the
NLO expressions. No assumptions are made about the equality of any parton
densities and the only symmetries utilised are charge conjugation invariance
and isotopic spin invariance of strong interactions.


title: Technicolor 2000

abstract:
  This review is based on lectures on technicolor and extended technicolor
presented at the Frascati Spring School in May 2000. I summarize the motivation
and structure of this theory of dynamical breaking of electroweak and flavor
symmetries. Particular attention is paid to the main phenomenological obstacles
to this picture-flavor-changing neutral currents, precision electroweak
measurements, and the large top-quark mass-and their proposed
resolutions-walking technicolor and topcolor-assisted technicolor. I then
discuss the signatures for technicolor and the existing and upcoming searches
for them at LEP, the Tevatron Collider, and the Large Hadron Collider. The
final section lists some outstanding theoretical questions.


title: The Singlet g_2 Structure Function in the Next-to-Leading Order

abstract:
  Following a previous study of the one-loop factorization of the nonsinglet
$g_2$ structure function of the nucleon, we present in this paper the
next-to-leading order coefficient functions in the singlet sector. To obtain
the result, the partonic processes of virtual Compton scattering off two and
three "on-shell" gluons are calculated. A key step in achieving the correct
factorization is to separate the correct twist-two contribution. The
Burkardt-Cottingham sum rule is nominally satisfied at this order.


title:
Minimal extended flavor groups, matter fields chiral representations,
  and the flavor question

abstract:
  We show the specific unusual features on chiral gauge anomalies cancellation
in the minimal, necessarily 3-3-1, and the largest
  3-4-1 weak isospin chiral gauge semisimple group leptoquark-bilepton
extensions of the 3-2-1 conventional standard model of nuclear and
electromagnetic interactions. In such models a natural explanation for the
fundamental question of fermion generation replication arises from the
self-consistency of a local gauge quantum field theory, which constrains the
number of the
  QFD fermion families to the QCD color charges.


title:
Higgs-mass predictions and electroweak precision observables in the
  Standard Model and the MSSM

abstract:
  Higher-order results for electroweak precision observables in the Standard
Model are analyzed in view of the experimental accuracies achievable at the
present and the next generation of colliders, and the indirect prediction of
the Higgs-boson mass from the precision data is discussed. Within the MSSM,
two-loop results for the lightest CP-even Higgs-boson mass are confronted with
the exclusion limits from LEP. Possible precision tests of the MSSM at a future
linear collider are furthermore investigated.


title:
Methods for the nonperturbative approximation of form factors and
  scattering amplitudes

abstract:
  Methods are described for the nonperturbative calculation of wave functions
and scattering amplitudes in light-cone quantization. Form factors are computed
from the boost-invariant wave functions, which appear as coefficients in a
Fock-state expansion of the field-theoretic eigenstate. A technique is proposed
for calculating scattering amplitudes from matrix elements of a T operator
between such composite-particle eigenstates.


title: Calculations with DLCQ

abstract:
  The method of discrete light-cone quantization (DLCQ) and useful refinements
are summarized. Applications to various field theories are reviewed.


title: Displaced Vertices in Extended Supersymmetric Models

abstract:
  In extended supersymmetric models with additional singlet Higgs fields
displaced vertices could be observed if the decay width of the next-to-lightest
supersymmetric particle becomes very small due to a singlino dominated LSP. We
study the supersymmetric parameter space where displaced vertices of the second
lightest neutralino exist in the NMSSM and an E6 inspired model. For a mass
difference between LSP and NLSP of more than 10 GeV the singlet vacuum
expectation value has to be at least of the order of 100 TeV in order to obtain
a lightest neutralino with a singlino component large enough for displaced
vertices.


title:
The Pomeron intercept in $\lambda\phi^3$ theory in 4 Minkowski + 1
  compact dimensions

abstract:
  We calculate the total cross section for two scalar particles scattering at
high energies in $\lambda\phi^3$ theory in five dimensions, four of which are
usual Minkowski ones and the fifth is compact. It is shown that the cross
section is dominated by exchange of Pomeron whose intercept is larger than in
usual four-dimensional case.


title: The Compatibility of the Gluon Reggeization with the s-channel Unitarity

abstract:
  Recently the non-forward BFKL kernel for interaction of two Reggeized gluons
in the antisymmetric colour octet state in the $t$-channel was obtained in the
next-to-leading order. It gives the possibility to check in this order the
bootstrap condition for this kernel, appearing as the requirement of the
compatibility of gluon Reggeization with the $s$-channel unitarity.


title: epsilon'/epsilon and Rare K and B Decays in the MSSM

abstract:
  We analyze the CP violating ratio epsilon'/epsilon and rare K and B decays in
the MSSM with minimal flavour and CP violation, including NLO QCD corrections
and imposing constraints on the supersymmetric parameters coming from epsilon,
B_{d,s}^0-\bar B_{d,s}^0 mixings, B to X_s gamma, Delta rho in the electroweak
precision studies and from the lower bound on the neutral Higgs mass. We
provide a compendium of phenomenologically relevant formulae in the MSSM.
Denoting by T(Q) the MSSM prediction for a given quantity normalized to the
Standard Model result we find the ranges: 0.53 < T(epsilon'/epsilon) < 1.07,
0.65 < T(K^+ to pi^+ nu nubar) < 1.02, 0.41 < T(K_L to pi^0 nu nubar) < 1.03,
0.48 < T(K_L to pi^0 e^+ e^-) < 1.10, 0.73 < T(B to X_s nu nubar) < 1.34 and
0.68 < T(B_s to mu^+ mu^-) < 1.53. We point out that these ranges will be
considerably reduced when the lower bounds on the neutral Higgs mass and tan
beta improve. Some contour plots illustrate the dependences of the quantities
above on the relevant supersymmetric parameters. As a byproduct of this work we
update our previous analysis of epsilon'/epsilon in the SM and find in NDR
epsilon'/epsilon = (9.2^{+6.8}_{-4.0}), a value 15 % higher than in our 1999
analysis.


title: Total Cross Sections and Event Properties from Real to Virtual Photons

abstract:
  A model for total cross sections with virtual photons is presented. In
particular gamma*-p and gamma*-gamma* cross sections are considered. Our
approach extends on a model for photoproduction, where the total cross section
is subdivided into three distinct event classes: direct, VMD and anomalous.
With increasing photon virtuality, the latter two decrease in importance.
Instead Deep Inelastic Scattering dominates, with the direct class being the
O(alpha_s) correction thereof. Hence, the model provides a smooth transition
between the two regions. By the breakdown into different event classes, one may
aim for a complete picture of all event properties.


title: Wandzura-Wilczek approximation for the twist-3 DVCS amplitude

abstract:
  We present a derivation of Wandzura-Wilczek (WW) like relations for skewed
parton distributions. It is demonstrated for photon-pion scattering that the
skewed twist-3 parton distributions contributing to the DVCS amplitude have
discontinuities at the points $x=\pm\xi$ in the WW approximation. This may lead
to a violation of factorisation for the twist-3 DVCS amplitude with transverse
polarization of the virtual photon. We show, however, that the contribution of
the divergencies to the scattering of a transversely polarized virtual photon
affects DVCS observables only at order $1/Q^2$ and can be neglected at twist-3
accuracy. For the scattering of a longitudinally polarized photon the twist-3
amplitude is free of such divergencies.


title: Observable contributions of new exotic quarks to quark mixing

abstract:
  Models with new vector-like quarks can produce observable quark mixing
effects which are forbidden in the Standard Model. We classify all such models
and write down the effective Lagrangian that results from integrating out the
new quarks. We study the relations between neutral and charged currents and
discuss how to distinguish among the different possibilities.


title:
New approach for calculating heavy-to-light form factors with QCD sum
  rules on the light-cone

abstract:
  We suggest a new approach for calculating heavy-to-light form factors. The
method is based on light cone sum rules (LCSR) and covers the whole kinematical
range of momentum transfer. The derivation of the new sum rule uses a suitable
combination of double and single dispersion integrals. As an example we give
numerical results for the form factor f^+ for the B -> pion transition.


title: Resolution of a long standing discrepancy in R with spin zero quarks

abstract:
  A previously successful dispersive method has been applied to understand
different values for $R(\sqrt{s} = 5 \div 7.5 GeV)$ obtained by MARK I and
Crystal Ball collaborations. We compute $R$ in the disputed region with data
from outside this region and asymptotic behavior given by the standard model
with 5 quark flavors, and find agreement with the Crystal Ball result. On the
other hand, the MARK I data are reproduced if we augment the asymptotic
behavior with contributions from a single spin zero quark of charge ($ -1/3$).
The visible hadronic fragments from such scalar quarks are not likely to
produce predominantly pure 2-jet events at such low energies. Hence, such decay
modes may have been removed by the Crystal Ball energy imbalance cuts in their
definition of hadronic events but not in MARK I events, thus accounting for the
discrepancy in the two results. Upper bounds on spin zero quark production at
LEP through $Z$ decay data are used to estimate the mixing angle between $T_3\
= -1/2$ and $T_3 = 0$ scalar quarks. Recent negative results about spin zero
quarks from CLEO are critically examined. We briefly discuss diquark production
hypothesis and find it very unlikely to explain the discrepancy.


title:
The Strong Isospin-Breaking Correction for the Gluonic Penguin
  Contribution to epsilon'/epsilon at Next-to-Leading Order in the Chiral
  Expansion

abstract:
  The strong isospin-breaking correction, Omega_{st}, which appears in
estimates of the Standard Model value for the direct CP-violating ratio
epsilon'/epsilon, is evaluated to next-to-leading order (NLO) in the chiral
expansion using Chiral Perturbation Theory. The relevant linear combinations of
the unknown NLO CP-odd weak low-energy constants (LEC's) which, in combination
with 1-loop and strong LEC contributions, are required for a complete
determination at this order, are estimated using two different models. It is
found that, to NLO, Omega_{st}=0.08 +/- 0.05, significantly reduced from the
``standard'' value, 0.25 +/- 0.08, employed in recent analyses. The potentially
significant numerical impact of this decrease on Standard Model predictions for
epsilon'/epsilon, associated with the decreased cancellation between gluonic
penguin and electroweak penguin contributions, is also discussed.


title: Kaon vs. Bottom: Where to look for a general MSSM?

abstract:
  We analyze CP violation and Flavor Changing effects in a general Minimal
Supersymmetric extension of the Standard Model with arbitrary non-universal
soft-breaking terms. We show that, in this conditions, large FCNC effects are
naturally expected in the Kaon system, even in the absence of quark-squark
flavor misalignment. On the other hand, the B system is only sensitive to new
supersymmetric contributions if the non-universality implies, not only
different soft term for the three generations but also the presence of a
quark-squark misalignment much larger that the corresponding CKM mixing. The
only exception to this rule are processes where the chirality changing
contributions proportional to tan beta are leading (for instance b -> s gamma).


title: Low-Scale Axion from Large Extra Dimensions

abstract:
  The mass of the axion and its decay rate are known to depend only on the
scale of Peccei-Quinn symmetry breaking, which is constrained by astrophysics
and cosmology to be between $10^9$ and $10^{12}$ GeV. We propose a new
mechanism such that this effective scale is preserved and yet the fundamental
breaking scale of $U(1)_{PQ}$ is very small (a kind of inverse seesaw) in the
context of large extra dimensions with an anomalous U(1) gauge symmetry in our
brane. Unlike any other (invisible) axion model, there are now possible
collider signatures in this scenario.


title: Selection rules in three-body B decay from factorization

abstract:
  Extending the dynamics underlying the factorization calculation of two-body
decays, we propose simple selection rules for nonresonant three-body B decays.
We predict, for instance, that in the Dalitz plot of B^0-->D^0-bar\pi^+\pi^-,
practically no events should be found in the corner of E(\pi^+) < \Lambda_{QCD}
as compared with the corner of E(\pi^-) < \Lambda_{QCD}. We also predict that
there should be very few three-body decay events with a soft meson resonance
and two energetic mesons or meson resonances. The selection rules are quite
different from the soft pion theorem, since they apply to different kinematical
regions. For B^0 -->D^0-bar\pi^+\pi^-, the latter predicts that the decay
matrix element vanishes in the zero-four-momentum limit of \pi^+ instead of
\pi^-. Since this marked difference from the soft pion theorem is directly
related to the issue of short-distance QCD dominance in the FSI of two-body B
decays, experimental test of the selection rules will shed light on strong
interaction dynamics of B decay.


title: Enhanced J/Psi Production in Deconfined Quark Matter

abstract:
  In high energy heavy ion collisions at the Relativistic Heavy Ion Collider
(RHIC) at Brookhaven and the Large Hadron Collider (LHC) at CERN, each central
event will contain multiple pairs of heavy quarks. if a region of deconfined
quarks and gluons is formed, a new mechanism for the formation of heavy
quarkonium bound states will be activated. This is a result of the mobility of
heavy quarks in the deconfined region, such that bound states can be formed
from a quark and an antiquark which were originally produced in separate
incoherent interactions. Model estimates of this effect for J/psi production at
RHIC indicate that significant enhancements are to be expected. Experimental
observation of such enhanced production would provide evidence for
deconfinement unlikely to be compatible with competing scenarios.


title:
Detection of weakly interacting light vector bosons by coherent
  scattering

abstract:
  We propose a novel experimental method to produce and detect weakly
interacting light vector bosons using coherent processes in refractive media. A
light vector boson would be produced by a laser photon scattered at a plane
interface between two media of different dielectric properties and will be
converted back to photon in the similar scattering process. The effect depends
strongly on the indices of refraction of the two media. If incident and
recovered photons were traveling through extremely high vacuums, limits on the
existence of several light vector bosons could be substantially improved.


title: Light Sgoldstino: Precision Measurements versus Collider Searches

abstract:
  We study sensitivity of low-energy experiments to the scale of supersymmetry
breaking $\sqrt{F}$ in models with light sgoldstinos --- superpartners of
goldstino. The limits on $\sqrt{F}$ may be obtained from direct and indirect
measurements of sgoldstino coupling to photons, leptons, mesons and nucleons.
There are three sources of constraints: ($i$) astrophysics and cosmology;
($ii$) precision laboratory experiments at low energies; ($iii$) rare decays.
We discuss only processes with real sgoldstinos. For sgoldstino lighter than a
few MeV and superpartner masses of the order of electroweak scale,
astrophysical and reactor bounds on $\sqrt{F}$ are significantly stronger than
limits which may be reached at future colliders. In models with heavier
sgoldstino (up to 5 GeV), constraints from flavor conserving decays of mesons
are complementary to ones coming from collider experiments. The most sensitive
probes of sgoldstinos are flavor violating processes, provided that flavor is
violated in squark and/or slepton sector. It is shown that sgoldstino
contributions into FCNC and lepton flavor violation are strong enough to probe
the supersymmetry breaking scale up to $\sqrt{F}\sim10^7$ GeV, if off-diagonal
entries in squark (slepton) mass matrices are close to the current limits in
MSSM.


title: Probe of CP Violation in e+e- -> ttbar Near Threshold

abstract:
  We report our theoretical study on how to probe the anomalous CP-violating
couplings of the top quark in the ttbar region at future e+e- linear colliders.
We focus on the unique role of the ttbar threshold region.


title: No-Scale Scenario with Non-Universal Gaugino Masses

abstract:
  Phenomenological issues of no-scale structure of K\"{a}hler potential are
re-examined, which arises in various approaches to supersymmetry breaking. When
no-scale boundary conditions are given at the Grand Unified scale and universal
gaugino masses are postulated, a bino mass is quite degenerate with
right-handed slepton masses and the requirement that the lightest superparticle
(LSP) be neutral supplemented with slepton searches at LEP200 severely
constrains allowed mass regions of superparticles. The situation drastically
changes if one moderately relaxes the assumption of the universal gaugino
masses. After reviewing some interesting scenarios where non-universal gaugino
masses arise, we show that the non-universality diminishes the otherwise severe
constraint on the superparticle masses, and leads a variety of superparticle
mass spectra: in particular the LSP can be a wino-like neutralino, a
higgsino-like neutralino, or even a sneutrino, and also left-handed sleptons
can be lighter than right-handed ones.


title: CP violation in B_d \to \phi K_S in SUSY GUT with right-handed neutrinos

abstract:
  CP violation in the B_d system is discussed in the supersymmetric grand
unified theory (GUT) with the right-handed neutrinos. Above the GUT scale, the
right-handed down-type squarks couple to the right-handed neutrinos. Due to the
renormalization group effect, flavor violations in the lepton sector may be
transfered to the right-handed down-type squark mass matrix, which affects the
CP violation in the B decay. Taking into account this effect, we compare the CP
violation in B_d \to \psi K_S and B_d \to \phi K_S processes. We will find that
a significant difference is possible between the CP violating phases in two
decay processes.


title: Electroweak Sudakov at two loop level

abstract:
  We investigate the Sudakov double logarithmic corrections to the form factor
of fermion in the SU(2)XU(1) electroweak theory. We adopt the familiar Feynman
gauge and present explicit calculations at the two loop level. We show that the
leading logarithmic corrections coming from the infrared singularities are
consistent with the "postulated" exponentiated electroweak Sudakov form factor.
The similarities and differences in the "soft" physics between the electroweak
theory and the unbroken non-abelian gauge theory (QCD) will be clarified.


title: Excited heavy baryon masses in HQET QCD sum rules

abstract:
  We construct the interpolating currents for the fourteen p-wave excited heavy
baryons in the framework of heavy quark effective theory (HQET). At the leading
order in the 1/m_Q expansion these interpolating currents do not mix different
states with the same J^P with each other. We use QCD sum rule to calculate the
masses of the p-wave excited J=1/2 spin doublet heavy baryons in the
m_Q~infinity limit. We discuss some implications of our results.


title: A Lorentz covariant approach to the bound state problem

abstract:
  The relativistic equivalent of the Schr\"odinger equation for a two particle
bound state having the total angular momentum $S$ is written in the form of a
Lorentz covariant set of equations (p_1^mu+p_2^mu+Omega^mu)Psi(p_1,p_2;P)
chi_S(\vec{p}_1,\vec{p}_2)=P^mu Psi(p_1,p_2;P) chi_S(\vec{p}_1,\vec{p}_2) where
the operators Omega^mu are the components of a 4-vector quasipotential. The
solution of this set is a stationary function representing the distribution of
spins and internal momenta in a reference frame where the momentum of the bound
system is P^\mu.
  The contribution of the operators Omega^mu to the bound state momentum is
assumed to be the 4-momentum of a vacuum-like effective field entering the
bound system as an independent component. It is shown that a state made of free
quarks and of the effective field has definite mass and can be normalized like
a single particle state.
  The generalization to the case of three or more particles is immediate.


title: Phase transition in linear sigma model and disoriented chiral condensate

abstract:
  We have investigated the phase transition and disoriented chiral condensate
domain formation in linear sigma model. Solving the equation of motion for the
sigma model fields in contact with a heat bath, we have shown that the fields
undergo phase transition above a certain critical temperature(T_c). It was also
shown that when the fields thermalised at temperature above T_c are cooled down
sufficiently rapidly, disoriented chiral condensate domains are formed quite
late in the evolution.


title: The ground state of bottomium to two loops and higher

abstract:
  We consider the properties of the ground state of bottomium. The $\Upsilon$
mass is evaluated to two loops, and including leading higher order
[$O(\alpha_s^5\log\alpha_s)$] and $m_c^2/m_b^2$ corrections. This allows us to
present updated values for the pole mass and $\bar{MS}$ mass of the $b$ quark:
$m_b=5022\pm58$ MeV, for the pole mass, and $\bar{m}_b(\bar{m}_b)=4286\pm36$
MeV for the $\bar{MS}$ one. The value for the \msbar mass is accurate including
and $O(\alpha_s^3)$ corrections and leading orders in the ratio $m_c^2/m_b^2$.
We then consider the wave function for the ground state of $\bar{b}b$, which is
calculated to two loops in the nonrelativistic approximation. Taking into
account the evaluation of the matching coefficients by Beneke and Signer one
can calculate, in principle, the width for the decay $\Upsilon\to e^+e^-$ to
order $\alpha_s^5$. Unfortunately, given the size of the corrections it is
impossible to produce reliable numbers. The situation is slightly better for
the ground state of toponium, where a decay width into $e^+e^-$ of 11 -- 14 keV
is predicted.


title: Phenomenology of Pseudo Dirac Neutrinos

abstract:
  We formulate general conditions on $3\times 3$ neutrino mass matrices under
which a degenerate pair of neutrinos at a high scale would split at low scale
by radiative corrections involving only the standard model fields. This
generalizes the original observations of Wolfenstein on pseudo Dirac neutrinos
to three generations. A specific model involving partially broken discrete
symmetry and solving the solar and atmospheric anomalies is proposed. The
symmetry pattern of the model naturally generates two large angles one of which
can account for the large angle MSW solution to the solar neutrino problem.


title: PHEGAS: a phase-space generator for automatic cross-section computation

abstract:
  A phase-space generation algorithm, capable to efficiently integrate the
squared amplitude of any scattering process, is presented. The algorithm has
been implemented in a Monte Carlo program, PHEGAS, which, using HELAC, a
helicity amplitude computational package,can be used for automatic
cross-section computation and event generation. Results for several scattering
processes with four, five and six particles in the final state are briefly
presented.


title: Squark Loop Correction to W^{+-} H^{-+} Associated Hadroproduction

abstract:
  We study the squark loop correction to W^{+-} H^{-+} associated
hadroproduction via gluon-gluon fusion within the minimal supersymmetric
extension of the standard model. We list full analytic results and
quantitatively analyze the resulting shift in the cross section at the CERN
Large Hadron Collider assuming a supergravity-inspired scenario.


title: Supersymmetric Quantum Corrections and Poisson-Lie T-Duality

abstract:
  The quantum actions of the (4,4) supersymmetric non-linear sigma model and
its dual in the Abelian case are constructed by using the background superfield
method. The propagators of the quantum superfield and its dual and the gauge
fixing actions of the original and dual (4,4) supersymmetric sigma models are
determined. On the other hand, the BRST transformations are used to obtain the
quantum dual action of the (4,4) supersymmetric non-linear sigma model in the
sense of Poisson-Lie T-duality


title: Tests of large-Nc QCD from hadronic tau decay

abstract:
  We use the Aleph data on vector and axial-vector spectral functions to test
simple duality properties of QCD in the large Nc limit, which emerge in the
approximation of a minimal hadronic ansatz of a spectrum of narrow states.
These duality properties relate the short- and long-distance behaviours of
specific correlation functions, which are order parameters of spontaneous
chiral symmetry breaking, in a way that we find well supported by the data.


title: The CKM Matrix and the Heavy Quark Expansion

abstract:
  These lectures contain an elementary introduction to heavy quark symmetry and
the heavy quark expansion. Applications such as the expansion of heavy meson
decay constants and the treatment of inclusive and exclusive semileptonic B
decays are included. The use of heavy quark methods for the extraction of
|V_cb| and |V_ub| is presented is some detail.


title: Mesonic fluctuations in a nonlocal Nambu-Jona-Lasinio model

abstract:
  The effects of meson fluctuations are studied in a nonlocal generalization of
the Nambu-Jona-Lasinio model, by including terms of next-to-leading order (NLO)
in 1/N_c. In the model with only scalar and pseudoscalar interactions NLO
contributions to the quark condensate are found to be very small. This is a
result of cancellation between virtual mesons and Fock terms, which occurs for
the parameter sets of most interest. In the quark self-energy, similar
cancellations arise in the tadpole diagrams, although not in other NLO pieces
which contribute at the \sim 25% level. The effects on pion properties are also
found to be small. NLO contributions from real $\pi\pi$ intermediate states
increase the sigma meson mass by $\sim 30%$. In an extended model with vector
and axial interactions, there are indications that NLO effects could be larger.


title: Physics of High-Mass Dimuon Production at the 50-GeV Proton Synchrotron

abstract:
  We discuss the physics interest and the experimental feasibility for
detecting high-mass dimuon pairs using the planned 50-GeV Proton Synchrotron
(PS) at the KEK/JHF and JAERI/NSP joint accelerator project. The Drell-Yan
measurement of $p+d$ versus $p+p$ at 50 GeV will provide unique information on
the flavor asymmetry of proton's up and down sea-quark distributions in the
large-$x$ region. A study of the nuclear dependences of Drell-Yan cross
sections can reveal the modification of antiquark distributions in nuclei.
Furthermore, the effect of energy loss for fast partons traversing nuclear
medium could also be sensitively measured. If polarized proton beam becomes
available at the 50-GeV PS, unique information on the sea-quark polarization
could be obtained. Study of heavy quarkonium production at the 50-GeV PS can
set important constraints on the mechanism of vector meson productions. Using a
prototype dimuon spectrometer, we have simulated the sensitivities for a
variety of measurements.


title: Gaugino Mass Dependence of Electron and Neutron Electric Dipole Moments

abstract:
  Unless squarks and sleptons are in the multi-TeV region or above, CP
violating induced electric dipole moments of elementary particles can pose
significant puzzles for supersymmetric (SUSY) models. We study the
dipole-moment-inducing one-loop amplitudes as a function of the fundamental
SUSY parameters and show that these puzzles are removed if there is a
sufficiently large hierarchy between the gaugino masses and the scalar mass. We
comment on the experimental status of the low gaugino mass scenario.


title: Fermionic Zero Modes on Domain Walls

abstract:
  We study fermionic zero modes in the domain wall background. The fermions
have Dirac and left- and right-handed Majorana mass terms. The source of the
Dirac mass term is the coupling to a scalar field $\Phi$. The source of the
Majorana mass terms could also be the coupling to a scalar field $\Phi$ or a
vacuum expectation value of some other field acquired in a phase transition
well above the phase transition of the field $\Phi$. We derive the fermionic
equations of motion and find the necessary and sufficient conditions for a zero
mode to exist. We also find the solutions numerically. In the absence of the
Majorana mass terms, the equations are solvable analytically. In the case of
massless fermions a zero energy solution exists and we show that although this
mode is not discretely normalizable it is Dirac delta function normalizable and
should be viewed as part of a continuum spectrum rather than as an isolated
zero mode.


title: QCD Sum Rules for Heavy Flavors

abstract:
  We give a short review of QCD sum rule results for B and D mesons and
Lambda_Q and Sigma_Q baryons. We focus mainly on recent developments concerning
semileptonic B->pion and D->pion transitions, pion couplings to heavy hadrons,
decay constants and estimates of the b quark mass from a baryonic sum rule, and
the extraction of the pion distribution amplitude from CLEO data.


title:
Vacuum Structure and the Axion Walls in Gluodynamics and QCD with Light
  Quarks

abstract:
  Large N gluodynamics was shown to have a set of metastable vacua with the
gluonic domain walls interpolating between them. The walls may separate the
genuine vacuum from an excited one, or two excited vacua which are unstable at
finite N (here N is the number of colors). One may attempt to stabilize them by
switching on the axion field. We study how the light quarks and the axion
affect the structure of the domain walls. In pure gluodynamics (with the axion
field) the axion walls acquire a very hard gluonic core. Thus, we deal with a
wall "sandwich" which is stable at finite N. In the case of the minimal axion,
the wall "sandwich" is in fact a "2-pi" wall, i.e., the corresponding field
configuration interpolates between identical hadronic vacua. The same
properties hold in QCD with three light quarks and very large number of colors.
However, in the realistic case of three-color QCD the phase corresponding to
the axion field profile in the axion wall is screened by a dynamical phase
associated with the eta-prime, so that the gluon component of the wall is not
excited. We propose a toy Lagrangian which models these properties and allows
one to get exact solutions for the domain walls.


title: Possible textures of neutrino and charged lepton mass matrices

abstract:
  We study a variety of different texture patterns in the basis in which the
charged lepton mass matrix or neutrino mass matrix or neither are diagonal. The
experimental results on the neutrinos provide sufficient restrictions to allow
only a small number of simple patterns. We discuss particularly the texture
zeroes which provide important relations among the mass eigenvalues and the
mixing matrix.


title:
Signature of Randall-Sundrum Quantum Gravity model in $\gamma\gamma$
  scattering in the TeV range

abstract:
  We examine the implications of the Randall-Sundrum gravity models on
$\gamma\gamma$ scattering in the TeV range.


title:
Relationship between the quark condensate and low-energy Pi-Pi
  observables beyond O(p^4)

abstract:
  The two-flavor Gell-Mann-Oakes-Renner ratio is expressed in terms of
low-energy pi-pi observables including the O(p^6) double chiral logarithms,
computed in Generalized Chiral Perturbation Theory. It is found that their
contribution is important and tends to compensate the one from the single
chiral logarithms.


title: Scalar Mesons and Chiral Symmetry

abstract:
  It is the purpose of the present manuscript to emphasize those aspects that
make the scalar sector with vacuum quantum numbers rather unique. Chiral
symmetry is the basic tool for our study together with a resummation of Chiral
Perturbation Theory (CHPT) that stresses the role of unitarity but also allows
one to include explicit resonance fields and to match with the CHPT expansion
at low energies.


title: Chiral fermions, orbifolds, scalars and fat branes

abstract:
  We note that orbifold boundary conditions that produce chiral fermion zero
modes in compactified higher dimensional theories may distort scalar field
vacuum expectation values, giving rise to nontrivial dependence on the extra
dimensions. We illustrate this in a simple five dimensional model which has
chiral fermion zero-modes stuck to fat branes. The model could provide a simple
and explicit realization of the separation of quarks and leptons in the fifth
dimension. We discuss the KK expansion in some detail. We find that there are
in general non-zero-mode states stuck to the brane, like the chiral zero modes.
We see explicitly the transition from states dominated by the internal
structure of the fat brane to those dominated by the compactification.