title:
Non-Equilibrium Statistical Mechanics of Classical Lattice $\phi^4$
  Field Theory

abstract:
  Classical $\phi^4$ theory in weak and strong thermal gradients is studied on
the lattice in (1+1) dimensions. Classical $\phi^4$ theory in weak and strong
thermal gradients is studied on the lattice in (1+1) dimensions. The steady
state physics of the theory is investigated from first principles and
classified into dynamical regimes. We derive the bulk properties associated
with thermal transport, and explore in detail the non-equilibrium statistical
mechanics of the theory as well as connections to equilibrium and irreversible
thermodynamics. Linear response predictions are found to be valid for systems
quite far from equilibrium and are seen to eventually break down simultaneously
with local equilibrium.


title: A Model Independent Determination of |V_{ub}|

abstract:
  It is shown that measuring the lepton invariant mass spectrum in inclusive
semileptonic B -> X_u l nu decay yields a model independent determination of
|V_{ub}|. Unlike the lepton energy and hadronic invariant mass spectra,
nonperturbative effects are only important in the resonance region, and play a
parametrically suppressed role when d\Gamma/dq^2 is integrated over q^2 >
(m_B-m_D)^2, which is required to eliminate the charm background. Perturbative
and nonperturbative corrections are presented to order \alpha_s^2\beta_0 and
\Lambda_{QCD}^2/m_b^2, and the \Lambda_{QCD}^3/m_b^3 corrections are used to
estimate the uncertainty in our results. The utility of the B -> X_s l^+ l^-
decay rate above the \psi(2S) resonance is discussed.


title:
Pion-nucleon scattering in chiral perturbation theory II: Fourth order
  calculation

abstract:
  We analyse elastic-pion nucleon scattering to fourth order in heavy baryon
chiral perturbation theory, extending the third order study published in Nucl.
Phys. A640 (1998) 199. We use various partial wave analyses to pin down the
low-energy constants from data in the physical region. The S-wave scattering
lengths are consistent with recent determinations from pionic hydrogen and
deuterium. We find an improved description of the P-waves. We also discuss the
pion-nucleon sigma term and problems related to the prediction of the
subthreshold parameters.


title: Central rapidity densities of charged particles at RHIC and LHC

abstract:
  Predictions on central rapidity densities of charged particles at energies of
the Relativistic Heavy Ion Collider and the Large Hadron Collider, for central
collisions between the largest nuclei that will be available at these
accelerators, are reviewed. Differences among the results of the existing
models are discussed in relation with their underlying physical basis and with
the possibilities to discriminate them.


title: Effect of CP-violation on the sphaleron rate

abstract:
  We calculate the effect of two CP-violating (dimension-eight) operators of
the SU(2)-Higgs model on the motion along a particular path from the vacuum to
the sphaleron. It turns out that CP-violation may introduce a difference
between the sphaleron rate towards larger Chern-Simons number and the rate
towards smaller Chern-Simons number. Such a difference induces a non-zero
baryon-number without a first order phase transition.


title: The eta' and the topological charge density

abstract:
  We compare two different frameworks which have been proposed to include the
eta' in chiral perturbation theory. The equivalence of these two approaches is
shown both for the purely mesonic case and in the presence of the ground state
baryon octet. The relation between the different sets of parameters in both
Lagrangians is clarified.


title:
Strong coupling constant from $\tau$ decay within renormalization scheme
  invariant treatment

abstract:
  We extract a numerical value for the strong coupling constant \alpha_s from
the \tau-lepton decay rate into nonstrange particles. A new feature of our
procedure is the explicit use of renormalization scheme invariance in
analytical form in order to perform the actual analysis in a particular
renormalization scheme. For the reference coupling constant in the
\MSsch-scheme we obtain \alpha_s(M_\tau)= 0.3184 \pm 0.0060_{exp} which
corresponds to \al_s(M_Z)= 0.1184 \pm 0.0007_{exp} \pm 0.0006_{hq mass}. This
new numerical value is smaller than the standard value from $\tau$-data quoted
in the literature and is closer to \al_s(M_Z)-values obtained from high energy
experiments.


title: CP Violation and Quark Mixing

abstract:
  Measurements of CP asymmetries in B decays will soon be made at $B$ factories
and hadron machines. In light of this, we review and update the profile of the
CKM unitarity triangle and the resulting CP asymmetries in B decays. This is
done both in the standard model and in several variants of the minimal
supersymmetric standard model (MSSM), which are characterized by a single phase
in the quark flavour mixing matrix. After imposing present constraints on the
parameters of these models, the predicted ranges of $\sin 2 \beta$ in the
standard model and in the MSSM are found to be similar. However, these theories
may be distinguished by future precise measurements of the other two
CP-violating phases $\alpha$ and $\gamma$.


title: Pseudo-Dirac Solar Neutrinos

abstract:
  Three of the viable solutions of the solar neutrino problem are consistent
with close to maximal leptonic mixing:
$\sin^2\theta_{12}={1\over2}(1-\epsilon_{12})$ with $|\epsilon_{12}|\ll1$.
Flavor models can naturally explain close to maximal mixing if approximate
horizontal symmetries force a pseudo-Dirac structure on the neutrino mass
matrix. An experimental determination of $|\epsilon_{12}|$ and
sign($\epsilon_{12}$) can constrain the structure of the lepton mass matrices
and consequently provide stringent tests of such flavor models. If both
$|\epsilon_{12}|$ and $\Delta m^2_{21}$ are known, it may be possible to
estimate the mass scale of the pseudo-Dirac neutrinos. Radiative corrections to
close to maximal mixing are negligible. Subtleties related to the kinetic terms
in Froggatt-Nielsen models are clarified.


title:
Heavy Quark Production at a Linear e^+e^- and Photon Collider and its
  Sensitivity to the Gluon Content of the Photon

abstract:
  A high energy linear e^+e^- collider (LC) can also be used as a Photon
Collider (PC), using Compton scattering of laser photons on the e^+/e^- beams.
The leading order cross-section for the production of heavy quarks, e^+e^- ->
e^+e^- Q(\bar{Q}) X, at high transverse momenta is calculated for both LC and
PC modes. The sensitivity of this process to the parton distribution
parametrizations of real photons, especially the gluon content, is tested for
both modes.


title: Bound on the tau neutrino magnetic moment from the TRISTAN experiments

abstract:
  We set limits on the magnetic moment and charge radius of the tau neutrino by
examining an extra contribution to the electroweak process $e^+ e^- \to \nu
\bar{\nu}\gamma$ using VENUS, TOPAZ and AMY results. We find that
$\kappa(\nu_{\tau}) < 9.1\times{10}^{-6}$
  (i.e. $\mu(\nu_{\tau}) < 9.1\times{10}^{-6}\mu_B, \mu_B = e/2m_e$) and $<r^2
> < 3.1\times{10}^{-31}$cm$^2$ with Poisson statistics by combining their
results. Whereas, similar to this method, with the Unified Approach we find
that $\kappa(\nu_{\tau}) < 8.0\times{10}^{-6}$ and $<r^2 > <
2.7\times{10}^{-31}$cm$^2$.


title: Determination of the CKM unitarity triangle parameters by end 1999

abstract:
  Within the Standard Model, a review of the current determination of the CKM
unitarity triangle parameters is presented, using experimental constraints from
the measurements of |epsilon_K|, V_ub/V_cb, Delta m_d and from the limit on
Delta m_s, available by end 1999.


title: Search for TeV Strings and New Phenomena in Bhabha Scattering at LEP2

abstract:
  A combined analysis of the data on Bhabha scattering at centre-of-mass
energies 183 and 189 GeV from the LEP experiments ALEPH, L3 and OPAL is
performed to search for effects of TeV strings in quantum gravity models with
large extra dimensions. No statistically significant deviations from the
Standard Model expectations are observed and lower limit on the string scale
M_S = 0.631 TeV at 95 % confidence level is derived. The data are used to set
lower limits on the scale of contact interactions ranging from 4.2 to 16.2 TeV
depending on the model. In a complementary analysis we derive an upper limit on
the electron size of 2.8 x 10^{-19} m at 95 % confidence level.


title: Is it possible to Measure the Weak Phase of a Penguin Diagram?

abstract:
  The $b\to d$ penguin amplitude receives contributions from internal $u$, $c$
and $t$-quarks. We show that it is impossible to measure the weak phase of any
of these penguin contributions without theoretical input. However, a single
assumption involving the hadronic parameters makes it possible to obtain the
weak phase and test for the presence of new physics in the $b\to d$
flavour-changing neutral current.


title:
Resonant Spin-Flavor Precession Solution to the Solar Neutrino Problem
  and electron antineutrinos from the Sun

abstract:
  We have found allowed squared mass difference, magnetic field, mixing angle -
regions for the Resonant Spin-Flavor Precession Solution to the Solar Neutrino
Problem fitted with the data of all acting solar neutrino experiments. The
typical mass difference region varying in dependence on the mixing angle is
allowed for some discrete magnetic field regions in a wide range for the fixed
neutrino transition magnetic moment. Except of the first allowed range with the
lowest field strength the magnetic field amplitude within other discrete
allowed regions depend essentially on the shape of a regular magnetic field
profile in the convective zone of the Sun. For the non-zero neutrino mixing one
can find at 99.9% C.L. an upper limit on the mixing, originated by the
non-observation of electron antineutrinos in the SuperKamiokande detector. This
limit occurs also sensitive to the magnetic field profile. While at 67% C.L.
there is another more stringent upper limit coming from inconsistency of the
gallium experiments with others. A new allowed region appears in the case of an
additional assumption that the Homestake data are 1.3 times less than the
experimental event rate.


title: Anomalous triple and quartic gauge boson couplings

abstract:
  This article reviews some recent developments in the analysis of anomalous
triple and quartic vector boson couplings that have been discussed at the UK
Phenomenology Workshop on Collider Physics 1999 in Durham.


title:
A method for determining anomalous gauge boson couplings from e^{+}e^{-}
  experiments

abstract:
  We present a model-independent method for determining anomalous gauge boson
couplings from ongoing and future e^{+}e^{-} -> W^{+} W^{-} experiments. First
we generalize an already existing method, which relies on the study of four
observables constructed through appropriate projections of the unpolarized
differential cross-section. In particular, we retain both linear and quadratic
terms in the unknown couplings, and compute contributions to these observables
originating from anomalous couplings which do not separately conserve the
discrete C, P, and T symmetries. Second, we combine the above set of
observables with three additional ones, which can be experimentally obtained
from the total cross-sections for polarized final state W bosons. The resulting
set of seven observables may provide useful information for constraining, and
in some cases for fully determining, various of the possible anomalous gauge
boson couplings.


title:
Radiative magnification of neutrino mixings and a natural explanation of
  the neutrino anomalies

abstract:
  We show that the neutrino mixing pattern with the large mixing required for
the atmospheric neutrino problem and the small mixing angle MSW solution for
the solar neutrino problem can be naturally generated through radiative
magnification, even though all the mixing angles at the seesaw scale may be
small. This can account for the neutrino anomalies as well as the CHOOZ
constraints in the context of quark-lepton unified theories, where the quark
and lepton mixing angles are expected to be similar in magnitude at the high
scale. We also indicate the 4$\nu$ mixing scenarios for which this mechanism of
radiative magnification can provide a natural explanation.


title: Graviscalars from higher-dimensional metrics and curvature-Higgs mixing

abstract:
  We investigate the properties of scalar fields arising from gravity
propagating in extra dimensions. In the scenario of large extra dimensions,
proposed by Arkani-Hamed, Dimopoulos and Dvali, graviscalar Kaluza-Klein
excitations are less important than the spin-2 counterparts in most processes.
However, there are important exceptions. The Higgs boson can mix to these
particles by coupling to the Ricci scalar. Because of the large number of
states involved, this mixing leads, in practice, to a sizeable invisible width
for the Higgs. In the Randall-Sundrum scenario, the only graviscalar is the
radion. It can be produced copiously at hadron colliders by virtue of its
enhanced coupling to two gluons through the trace anomaly of QCD. We study both
the production and decay of the radion, and compare it to the Standard Model
Higgs boson. Furthermore, we find that radion detectability depends crucially
on the curvature-Higgs boson mixing parameter.


title: The masses of the mesons and baryons. Part I. The Integer Multiple Rule

abstract:
  From the well-known decays of the particles follows that the mesons and
baryons consist of a $\gamma$-branch and a neutrino branch. From the well-known
masses of the particles follows that the masses of the $\gamma$-branch
particles are integer multiples of the mass of the $\pi^0$ meson, within 3%, in
spite of differences in spin, isospin, strangeness and charm. The average
factor in front of the integer multiples of $m(\pi^0)$ of the $\gamma$-branch
particles is $1.0073 \pm 0.0184$. The masses of the $\nu$-branch particles are
integer multiples of the mass of the $\pi^\pm$ mesons, times a factor $0.86 \pm
0.02$. The existence of the integer multiple rule can be verified from the
Particle Physics Summary using a calculator.


title: A short course in effective Lagrangians

abstract:
  These lectures provide an introduction to effective theories concentrating on
the basic ideas and providing some simple applications


title:
A comment on baryogenesis at the electroweak scale in alternative
  cosmologies

abstract:
  In this study we examine post-inflationary cosmologies dominated by a scalar
field with the equation of state: p_phi=w_phi rho_phi (0 leq w_phi leq 1) in
order to facilitate baryogenesis at the electroweak scale. We take a more
conventional approach from one in Ref. 1 [Joyce, Prokopec] and assume that the
Universe reheats by the scalar field decay before the nucleosynthesis epoch,
and find a larger expansion rate at the electroweak scale than the one obtained
in Ref. 1. The decaying field models suffer however from an entropy release
that dilutes the baryon number produced at the electroweak scale. This dilution
is minimized when the kinetic scalar field mode dominates (w_phi = 1), singling
it out as the preferred cosmology with regard to baryogenesis. We study both
cases, the electroweak transition with an expansion driven departure from
equilibrium, and a first order phase transition. We show that in the former
case with some tuning one can produce the amount of matter consistent with
observation. In the latter case the expansion rate at the electroweak scale may
be almost as large as the symmetric phase sphaleron rate, so that even the
electroweak models with a relatively weak first order phase transition can be
viable for baryogenesis.


title:
Phenomenology of the Flavor-Asymmetry in the Light-Quark Sea of the
  Nucleon

abstract:
  A phenomenological ansatz for the flavor-asymmetry of the light sea
distributions of the nucleon, based on the Pauli exclusion principle, is
proposed. This ansatz is compatible with the measured flavor-asymmetry of the
unpolarized sea distributions, $\bar{d}>\bar{u}$, of the nucleon. A prediction
for the corresponding polarized flavor-asymmetry is presented and shown to
agree with predictions of (chiral quark--soliton) models which successfully
reproduced the flavor-asymmetry of the unpolarized sea.


title: Production of light stabilized radion at high energy hadron collider

abstract:
  In this paper we use the conformal anomaly in QCD to derive the coupling of
light radion to gluons in the Randall-Sundrum model and use it to compute the
radion production cross section at hadron colliders by gluon fusion. We find
that the radion production cross section by gluon fusion at LHC would exceed
that of the higgs boson by a factor that lies between 7 and 8 over most of the
range. The decay modes of the radion are similar to that of the SM higgs boson.
But the striking feature is the enhancement of radion to 2-photon and radion to
2-gluon branching ratio over the SM case. Utilising this, we then discuss the
possible search strategies of such scalars at Tevatron and LHC. Using the
$\gamma \gamma$ decay mode one can explore/exclude radion mass upto 1 TeV. Even
with the current collected data at the Tevatron, one can exclude radion mass
upto 120 GeV for $\vphi$= 1 TeV.


title:
Finite width effects and gauge cancellations in W- and Z-boson
  production in framework of modified perturbation theory

abstract:
  The processes of production and subsequent decay of W- and Z-bosons in $e^+
e^-$ collisions are considered in a recently proposed modified perturbation
theory (PT), based on a direct expansion of probabilities instead of
amplitudes. In such an approach the non-integrable singularities in the phase
space, which are intrinsic in the conventional PT, appear as singularities in
the coupling constant (with subsequent compensation by the decay factors of
unstable particles). In the present paper the systematic investigation of the
modified PT is carried out. The results are compared with the results of the
conventional approach, based on calculation of the amplitude with Dyson
resummation. A solution to the problem of the loss of one-loop PT order in the
resonance region is found. On the basis of this solution the proof of gauge
cancellations in any order of the modified PT is given. A simple generalization
of the fermion-loop scheme is proposed which provides a complete description of
W-pair production in next-to-leading order approximation.


title:
Axial Symmetry and Bound States of Particles with Anomalous Magnetic
  Moment

abstract:
  We consider bound states of fermions with an anomalous magnetic moments in
the field of charged cylinder.Also we obtain second order equations for axially
symmetric $Z_0(r)$-boson field, radial axially symmetric magnetic field, obtain
second order equations for case of bound states of fermions in the radial
electric and magnetic fields.


title: On the Size of the Dark Side of the Solar Neutrino Parameter Space

abstract:
  We present an analysis of the MSW neutrino oscillation solutions of the solar
neutrino problem in the framework of two-neutrino mixing in the enlarged
parameter space $(\Delta m^2, \tan^2\theta)$ with $\theta \in
(0,\frac{\pi}{2})$. Recently, it was pointed out that the allowed region of
parameters from a fit to the measured total rates can extend to values $\theta
\geq \frac{\pi}{4}$ (the so called ``dark side'') when higher confidence levels
are allowed. The purpose of this letter is to reanalize the problem including
all the solar neutrino data available, to discuss the dependence on the
statistical criteria in the determination of the CL of the ``dark side'' and to
extract the corresponding limits on the largest mixing allowed by the data. Our
results show that when the Super-Kamiokande data on the zenith angle
distribution of events and the spectrum information is included, the regions
extend more into the dark side.


title: High Temperature Symmetry Nonrestoration

abstract:
  This is a short review on the subject of symmetry nonrestoration at high
temperature. Special emphasis is put on experimental discoveries and different
theoretical mechanisms. At the end, possible cosmological applications are
briefly mentioned.


title: Quantifying Baryon Stopping in High Energy Nuclear Collisions

abstract:
  We propose a numerical definition for baryon stopping in relativistic heavy
ion collisions that is obtainable from final hadron rapidity distributions as
well as from bremsstrahlung measurements. Thus a new channel of communication
is opened between the two methods.


title:
The phi --> pi^+ pi^- and phi radiative decays within a chiral unitary
  approach

abstract:
  We report on recent results on the decay of the phi into pi^+ pi^- and phi
radiative decays into pi^0 pi^0 gamma and pi^0 eta gamma, which require the
consideration of the final state interaction of a pair of mesons in a region
inaccessible to Chiral Perturbation Theory. By using nonperturbative chiral
unitary methods for the meson meson interaction we can obtain the corresponding
decay widths and the results are compared with recent experimental data.


title:
Central Baryons in Dual Models and the Possibility of a Backward Peak in
  Diffraction

abstract:
  Two distinct interactions of Pomerons should occur in dense multi-string
events. Besides the usual triple Pomeron processes transitions to membraned
cylinders can be expected to contribute in a significant way. They offer an
efficient mechanism for central baryon production and for the long range
transport of initial baryons. The slope of such an exchange should be quite low
as it is related to the Odderon known from the leading logarithmic
approximation. Such a flat trajectory has to be suppressed by small coupling
constants. It is argued that this strong suppression does not appear in
diffractive events. In consequence there should be a tiny observable backward
peak in the initial baryon distribution even in quite massive diffractive
systems.


title: Aspects of GMSB Phenomenology at TeV Colliders

abstract:
  The status of two on-going studies concerning important aspects of the
phenomenology of gauge-mediated supersymmetry breaking (GMSB) models at TeV
colliders is reported. The first study deals with the characteristics of the
light Higgs boson spectrum allowed by the (minimal and non-minimal) GMSB
framework. Today's most accurate GMSB model generation and two-loop
Feynman-diagrammatic calculation of m_h have been combined. The Higgs masses
are shown in dependence of various model parameters at the messenger and
electroweak scales. In the minimal model, an upper limit on m_h of about 124
GeV is found for m_t = 175 GeV. The second study is focused on the measurement
of the fundamental SUSY breaking scale sqrt(F) at the LHC in the GMSB scenario
where a stau is the next-to-lightest SUSY particle (NLSP) and decays into a
gravitino with c*tau_NLSP in the range 0.5 m to 1 km. This implies the
measurement of mass and lifetime of long lived sleptons. The identification is
performed by determining the time of flight in the ATLAS muon chambers.
Accessible range and precision on sqrt(F) achievable with a counting method are
assessed.


title: Modification of Z Boson Properties in Quark-Gluon Plasma

abstract:
  We calculate the change in the effective mass and width of a Z boson in the
environment of a quark-gluon plasma under the conditions expected in Pb-Pb
collisions at the LHC. The change in width is predicted to be only about 1 MeV
at a temperature of 1 GeV, compared to the natural width of 2490$\pm$7 MeV. The
mass shift is even smaller. Hence no observable effects are to be expected.


title:
Chiral Unitary approach to meson-meson and meson-baryon interactions and
  nuclear applications

abstract:
  We report on recent nonperturbative techniques that combine the information
of chiral Lagrangians (with and without resonances) with unitarity in coupled
channels and other requirements of the S-matrix theory of the strong
interactions. As a result, the region of applicability of such techniques is
much larger than the one of Chiral Perturbation Theory allowing one to study
also resonance physics. Applications to meson-meson and meson-baryon
scattering, as well as to problems where pairs of mesons or a meson and a
baryon appear in the initial or final state are shown. Implications in several
nuclear problems are also discussed.


title: Weak Scale Inflation and Unstable Domain Walls

abstract:
  Cosmlogical domain walls produced during phase transition are expected to
collapse on a cosmologically safe timescale if Vilenkin's condition is
satisfied. We show that the decaying processes of these unstable domain walls
should be changed significantly if weak scale inflation takes place. The usual
condition for the safe decay of the cosmological domain wall must be changed,
depending on their scales and interactions. As a result, the energy scales and
explicit breaking terms of such walls must satisfy severe requirements. We also
make a brief comment on cosmological structure formation.


title: Deeply virtual Compton scattering at small x

abstract:
  We calculate the cross section of the deeply virtual Compton scattering at
large energies and intermediate momentum transfers.


title:
Thermal Equilibration and Ellipsoidal Expansion of
  Rotationally-Symmetrical Longitudinal Flow in Relativistc Heavy Ion
  Collisions

abstract:
  A rotationally-symmetrical ellipsoidal flow model is proposed for the
relativistic heavy-ion collisions and compared with the 14.6 A GeV/c Si-Al and
10.8 A GeV/c Au-Au collision data. The large stopping in the heavier collision
system and heavier produced particles is accounted for by using the ellipsoidal
flow picture. The central dip in the proton and deuteron rapidity distributions
for Si-Al collision are reproduced.


title: Primordial Magnetic Fields and Electroweak Baryogenesis

abstract:
  In this contribution we will shortly review the main mechanism through which
primordial magnetic fields may affect the electroweak baryogenesis. It is shown
that although strong magnetic fields might enhance the strength of the
electroweak phase transition, no benefit is found for baryogenesis once the
effect of the field on the sphaleron rate is taken into account. The possible
role of hypermagnetic helicity for the electroweak baryogenesis is shortly
discussed.


title: Energy loss in perturbative QCD

abstract:
  We review the properties of energetic parton propagation in hot or cold QCD
matter, as obtained in recent works. Advances in understanding the energy loss
- collisional and radiative - are summarized, with emphasis on the latter: it
features very interesting properties which may help to detect the quark-gluon
plasma produced in heavy ion collisions. We describe two different theoretical
approaches, which lead to the same radiated gluon energy spectrum. The case of
a longitudinally expanding QCD plasma is investigated. The energy lost by a jet
with given opening angle is calculated in view of making predictions for the
suppression (quenching) of hard jet production. Phenomenological implications
for the difference between hot and cold matter are discussed. Numerical
estimates of the loss suggest that it may be significantly enhanced in hot
compared to cold matter.


title: Neutrino oscillations and large extra dimensions

abstract:
  Assuming that right-handed neutrinos exist and propagate in some large extra
dimensions, we attempt to give a comprehensive description of the phenomenology
of neutrino oscillations. A few alternative explanations of the atmospheric
neutrino anomaly emerge, different from the standard nuMu --> nuTau or nuMu -->
nuSterile interpretations. Constraints from nucleosynthesis and supernova 1987a
are discussed. The constraints from SN1987a indicates a maximum radius of any
extra dimension of about 1 Angstrom.


title:
Strange quark polarization of the nucleon: A parameter-independent
  prediction of the chiral potential model

abstract:
  We perform a one-loop calculation of the strange quark polarization ($\Delta
s$) of the nucleon in a SU(3) chiral potential model. We find that if the
intermediate excited quark states are summed over in a proper way, i.e., summed
up to a given energy instead of given radial and orbital quantum numbers,
$\Delta s$ turns out to be almost independent of {\em all} the model
parameters: quark masses, scalar- and vector-potential strengths. The
contribution from the quark-antiquark pair creation and annihilation ``$Z$''
diagrams is found to be significant. Our numerical results agree quite
reasonably with experiments and lattice QCD calculations.


title: Substructure of the Nucleon in the Chiral Quark Model

abstract:
  The spin and orbital angular momentum carried by different quark flavors in
the nucleon are calculated in the SU(3) chiral quark model with
symmetry-breaking. The similar calculation is also performed for other octet
and decuplet baryons. Furthermore, the flavor and spin contents for charm and
anti-charm quarks are predicted in the SU(4) symmetry breaking chiral quark
model.


title: Charmed hadrons production in high-energy $\Sigma^-$ beam

abstract:
  We present the calculation of the inclusive x_F-distributions of charmed
hadrons, produced in high-energy $\Sigma^-$-beam. Our calculation is based on
the modified mechanism of charmed quarks fragmentation as well as on the
mechanism of c-quark recombination with the valence quarks from initial
hadrons.


title:
Model independent bounds on the tau lepton electromagnetic and weak
  magnetic moments

abstract:
  Using LEP1, SLD and LEP2 data, for tau lepton production, and data from CDF,
D0 and LEP2, for W decays into tau leptons, we set model independent limits on
non-standard electromagnetic and weak magnetic moments of the tau lepton. The
most general effective Lagrangian giving rise to tau moments is used without
further assumptions. Precise bounds ($2\sigma$) on the non-standard model
contributions to tau electromagnetic ($-0.007<a_\gamma< 0.005$), tau Z-magnetic
($-0.0024 <a_Z< 0.0025$) and tau W-magnetic ($-0.003 < \kappa^W < 0.004$)
dipole moments are set from the analysis.


title:
Complete Renormalization Group Improvement-Avoiding Factorization and
  Renormalization Scale Dependence in QCD Predictions

abstract:
  For moments of leptoproduction structure functions we show that all
dependence on the renormalization and factorization scales disappears, provided
that all the ultraviolet logarithms involving the physical energy scale Q are
completely resummed. The approach is closely related to Grunberg's method of
Effective Charges. A direct and simple method for extracting the universal
dimensional transmutation parameter of QCD from experimental data is advocated.


title: The Standard Model instability and the scale of new physics

abstract:
  We apply a general formalism for the improved effective potential with
several mass scales to compute the scale M of new physics which is needed to
stabilize the Standard Model potential in the presence of a light Higgs. We
find, by imposing perturbativity of the new physics, that M can be as large as
one order of magnitude higher than the instability scale of the Standard Model.
This implies that, with the present lower bounds on the Higgs mass, the new
physics could easily (but not necessarily) escape detection in the present and
future accelerators.


title:
Squark-Chargino Production in Polarized Gamma-Proton Collisions at TeV
  Energy Scale

abstract:
  The associated production of squarks and charginos in high energy collisions
of the polarized real photons and protons is discussed. We give the cross
sections for different initial beam polarizations and the polarization
asymmetries which can be used to anticipate the masses of squarks and
charginos.


title: Theoretical Update on Rare K Decays

abstract:
  We review the status of rare kaon decays, concentrating on modes with
sensitivity to short-distance flavour physics.


title:
Effects of the right-handed neutrinos on \Delta S = 2 and \Delta B = 2
  processes in supersymmetric SU(5) model

abstract:
  We discuss an extra source of CP and flavor violations in supersymmetric
SU(5) grand unified model with the right-handed neutrinos. In such a model, the
right-handed down-type squarks \tilde{d}_R interact with the right-handed
neutrinos above the GUT scale, and the renormalization group effect can
generate sizable off-diagonal elements in the mass matrix of \tilde{d}_R.
Because of new Yukawa phases which exist in the SU(5) model, these off-diagonal
elements have, in general, large CP violating phases. The renormalization group
induced off-diagonal elements affect the K and B decays. In particular, in this
model, supersymmetric contribution to the \epsilon_K parameter can be as large
as the currently measured experimental value, and hence the effect might be
seen as an anomaly in the on-going test of the Cabibbo-Kobayashi-Maskawa
triangle.


title: Meson Masses in High Density QCD

abstract:
  The low-energy effective theories for the two- and three-flavor
color-superconductors arising in the high density limit of QCD are discussed.
Using an effective field theory to describe quarks near the fermi surface, we
compute the masses of the pseudo-Goldstone bosons that dominate the
low-momentum dynamics of these systems.


title: CP Violation in Hyperon Decays

abstract: The theory and phenomenology of CP violation in hyperon decays is summarized.


title:
Exact O(g^2 alpha_s) top decay width from general massive two-loop
  integrals

abstract:
  We calculate the b-dependent self-energy of the top quark at O(g^2 \alpha_s)
by using a general massive two-loop algorithm proposed in a previous article.
  From this we derive by unitarity the O(\alpha_s) radiative corrections to the
decay width of the top quark, where all effects associated with the $b$ quark
mass are included without resorting to a mass expansion. Our results agree with
the analytical results available for the O(\alpha_s) correction to the top
quark width.


title:
Dynamical fermion masses under the influence of Kaluza-Klein fermions in
  extra dimensions

abstract:
  The dynamical fermion mass generation in the 4-dimensional brane is discussed
in a model with 5-dimensional Kaluza-Klein fermions in interaction with
4-dimensional fermions. It is found that the dynamical fermion masses are
generated beyond the critical radius of the compactified extra dimensional
space and may be made small compared with masses of the Kaluza-Klein modes.


title:
FeynHiggsFast: a program for a fast calculation of masses and mixing
  angles in the Higgs Sector of the MSSM

abstract:
  FeynHiggsFast is a Fortran code for the calculation of the masses and the
mixing angle of the neutral CP-even Higgs bosons in the MSSM up to two-loop
order. It is based on a compact analytical approximation formula of the
complete diagrammatic one-loop and the dominant two-loop contributions. At the
one-loop level a leading logarithmic result is used, taking into account all
sectors of the MSSM. At the two-loop level at O(alpha alpha_s) the leading
logarithmic and non-logarithmic contributions are taken into account. The
approximation formula is valid for arbitrary choices of the parameters in the
Higgs sector of the model. Comparing its quality to the full diagrammatic
result, we find agreement better than 2 GeV for most parts of the MSSM
parameter space.


title:
Inflationary models with a flat potential enforced by non-abelian
  discrete gauge symmetries

abstract:
  Non-abelian discrete gauge symmetries can provide the inflaton with a flat
potential even when one takes into account gravitational strength effects. The
discreteness of the symmetries also provide special field values where
inflation can end via a hybrid type mechanism. An interesting feature of this
method is that it can naturally lead to extremely flat potentials and so, in
principle, to inflation at unusually low energy scales. Two examples of
effective field theories with this mechanism are given, one with a hybrid exit
and one with a mutated hybrid exit. They include an explicit example in which
the single field consistency condition is violated.


title:
Effects of New Gravitational Interactions on Neutrinoless Double Beta
  Decay

abstract:
  It has recently been proposed that violations of Lorentz invariance or
violations of the equivalence principle can be constrained from the
non-observation of neutrinoless double beta decay. We generalize this analysis
to all possible new gravitational interactions and discuss briefly the
constraints for different cases.


title: Long-distance effects in $B\to V\gamma$ radiative weak decays

abstract:
  A systematic approach to long-distance effects in exclusive radiative weak
$B$ decays is presented, based on a combination of the heavy quark limit with
perturbative QCD. The dominant long-distance effects, connected with weak
annihilation and $W$-exchange topologies, can be computed in a
model-independent way using experimental data on $B$ radiative leptonic decays.
Nonfactorizable corrections vanish in the chiral limit and to leading twist.
The left-handed photon amplitudes are shown to be enhanced relative to the
right-handed ones, both in the long- and short-distance parts of the $\bar B$
decay amplitudes. We discuss the implications of our results for the extraction
of $|V_{td}|$.


title:
Implications of the Unitarity Triangle `uc' for J, $\delta$ and
  $|V_{CKM}|$ elements

abstract:
  The Jarlskog rephasing invariant parameter $|J|$ is evaluated using one of
the six Unitarity Triangles involving well known CKM matrix elements \vud,
\vus,~\rub, ~\vcd, ~\vcs~ and ~\vcb. With PDG2000 values of \vud~ etc. as
input, we obtain $|J|=(2.71 \pm 1.12) \times 10^{-5}$, which in the PDG
representation of CKM matrix leads to the range $21^o~to~159^o$ for the CP
violating phase $\delta$. The CKM matrix elements evaluated using this range of
$\delta$ are in agreement with the PDG CKM matrix. The implications of
refinements in the input on $|J|$, $\delta$ and CKM matrix elements have also
been studied.


title:
T-odd quark fragmentation function and transverse spin asymmetries in
  the pion production

abstract:
  We study the time-reversal odd quark fragmentation function and its
consequences on the hard processes. T-odd quark fragmentation function may
arise, although QCD is T-invariant, from the non-perturbative dynamics in the
fragmentation process. Assuming the factorization, we extract the T-odd
fragmentation function from the inclusive pion production in the transversely
polarized proton-proton collision. We then estimate the single spin asymmetry
$A_{OT}$ of the semi-inclusive deep inelastic scattering with unpolarized
lepton and the transversely polarized proton. We also discuss the meson cloud
effects on the transversity distribution $h_1(x)$ of the nucleon. Asymmetry for
the $\pi^-$ production is found to be much smaller than the naive expectation,
since the $d$-quark transversity is considerably suppressed by the pion cloud
effects


title: Baryogenesis through axion domain wall

abstract:
  Generic axion models give rise to axion domain walls in the early Universe
and they have to disappear not to overclose the universe, thus limiting the
nature of discrete symmetry allowed in these type of models. Through QCD
sphalerons, net chiral charge can be created by these collapsing walls which in
turn can result the observed baryon assymmetry.


title: Three-body Supersymmetric Top Decays

abstract:
  We discuss three-body supersymmetric top decays, in schemes both with and
without R-parity conservation, assuming that sfermion masses are larger than
m_t. We find that MSSM top decays into chargino/neutralino pairs have a strong
kinematic suppression in the region of the supersymmetric parameter space
consistent with the LEP limits, with a decay width =< 10^{-5} GeV. MSSM top
decays into neutralino pairs have less kinematical suppression, but require a
flavour-changing vertex, and are likely to have a smaller rate. On the other
hand, R-violating decays to single charginos, neutralinos and conventional
fermions can be larger for values of the R-violating couplings still permitted
by other upper limits. The cascade decays of the charginos and neutralinos may
lead to spectacular signals with explicit lepton-number violation, such as
like-sign lepton events.


title: Open system approach to neutrino oscillations

abstract:
  Neutrino oscillations are studied in the general framework of open quantum
systems by means of extended dynamics that take into account possible
dissipative effects. These new phenomena induce modifications in the neutrino
oscillation pattern that in general can be parametrized by means of six
phenomenological constants. Although very small, stringent bounds on these
parameters are likely to be given by future planned neutrino experiments.


title:
Pauli-Villars regularization and discrete light-cone quantization in
  Yukawa theory

abstract:
  The techniques of Pauli-Villars regularization and discrete light-cone
quantization are combined to analyze Yukawa theory in a single-fermion
truncation. A special form of the Lanczos algorithm is constructed for
diagonalization of the indefinite-metric light-cone Hamiltonian.


title:
Cosmological and astrophysical bounds on a heavy sterile neutrino and
  the KARMEN anomaly

abstract:
  Constraints on the lifetime of the heavy sterile neutrino, that was proposed
as a possible interpretation of the KARMEN anomaly, are derived from primordial
nucleosynthesis and SN 1987A. Together with the recent experimental bounds on
the nu_s lifetime, SN 1987A completely excludes this interpretation.
Nucleosynthesis arguments permit a narrow window for the lifetime in the
interval 0.1-0.2 sec. If nu_s possesses an anomalous interaction with nucleons,
the SN bounds may not apply, while the nucleosynthesis ones would remain valid.


title: Phenomenology of the radion in Randall-Sundrum scenario at colliders

abstract:
  Phenomenology of a radion ($\phi$) that stabilizes the modulus in the
Randall-Sundrum scenario is considered. The radion couples to the trace of
energy momentum tensor of the standard model (SM) with a strength suppressed
only by a new scale ($\Lambda_{\phi}$) of an order of the electroweak scale. In
particular, the effective coupling of a radion to two gluons are enhanced due
to the trace anomaly of QCD. Therefore, its production cross section at hadron
colliders could be enhanced, and the dominant decay mode of a relatively light
radion is $\phi$ -> g g, unlike the SM Higgs boson case. We also present
constraints on the mass $m_{\phi}$ and the new scale $\Lambda_{\phi}$ from the
Higgs search limit at LEP and perturbative unitarity bound.


title: Exact and Broken Symmetries in Particle Physics

abstract:
  In these lectures, I discuss the role of symmetries in particle physics. I
begin by discussing global symmetries and show that they can be realized
differently in nature, depending on whether or not the vacuum state is left
invariant by the symmetry. I introduce next the notion of local symmetries and
show how these symmetries can be implemented through the introduction of gauge
fields. Using the simple example of a spontaneously broken U(1) symmetry, I
discuss the Higgs mechanism showing that it provides a natural way for the
gauge fields to acquire mass. Finally, I show how these concepts are used as
the basis for the Standard Model of particle physics, ending with a brief
description of some of the salient aspects of Quantum Chromodynamics and of the
electroweak theory.


title: Either neutralino dark matter or cuspy dark halos

abstract:
  We show that if the neutralino in the minimal supersymmetric standard model
is the dark matter in our galaxy, there cannot be a dark matter cusp extending
to the galactic center. Conversely, if a dark matter cusp extends to the
galactic center, the neutralino cannot be the dark matter in our galaxy. We
obtain these results considering the synchrotron emission from neutralino
annihilations around the black hole at the galactic center.


title:
Weak Phase $\gamma$ and Strong Phase $\delta$ from CP Averaged $B\to
  \pi\pi$ and $\pi K$ Decays

abstract:
  Assuming SU(3) symmetry for the strong phases in the four decay modes
$B\rarrow \pi^-\pi^+, \pi^0 \pi^+, \pi^- K^+, \pi^- \bar{K}^0$ and ignoring the
relative small electroweak penguin effects in those decays, the weak phase
$\gamma$ and the strong phase $\delta$ can be determined in a model independent
way by the CP-averaged branching ratios of the four decay modes. It appears
that the current experimental data for $B\to \pi\pi$ and $\pi K$ decays prefer
a negative value of $\cos\gamma\cos\delta$. By combining with the other
constraints from $V_{ub}$, $B^{0}_{d,s}-\bar{B}^{0}_{d,s}$ mixings and indirect
CP-violating parameter $\epsilon_K$ within the standard model, two favorable
solutions for the phases $\gamma$ and $\delta$ are found to lie in the region:
$35^{\circ}\alt\gamma\alt 62^{\circ}$ and $106^{\circ}\alt \delta \alt
180^{\circ}$ or $86^{\circ}\alt\gamma\alt 151^{\circ}$ and
$0^{\circ}\alt\delta\alt 75^{\circ} $ within 1$\sigma$ standard deviation. It
is noted that if allowing the standard deviation of the data to be more than
1$\sigma$, the two solutions could approach to one solution with a much larger
region for the phases $\gamma$ and $\delta$. Direct CP asymme try
$a_{\epsilon''}^{(\pi^- K^+)}$ in $B\rarrow \pi^-K^+$ decay can be as large as
the present experimental upper bound. Direct CP asymmetry
$a_{\epsilon''}^{(\pi^+\pi^-)}$ in $B\rarrow \pi^-\pi^+$ decay can reach up to
about 40% at 1$\sigma$ level.


title: Magnetic Moments of Delta Baryons in Light Cone QCD Sum Rules

abstract:
  We calculate the magnetic moments of Delta baryons within the framework of
QCD sum rules. A comparison of our results on the magnetic moments of the Delta
baryons with the predictions of different approaches is presented.


title: Static Solutions for Brane Models with a Bulk Scalar Field

abstract:
  We present static solutions of the 5-dimensional Einstein equations in the
brane-world scenario by using two different approaches for the stabilization of
the extra dimension. Assuming a ``phenomenological'' stabilization mechanism,
that creates a non-vanishing $\hat T^5_5$ in the bulk, we construct a two-brane
model, which allows both branes to have positive self-energies. We then
consider a candidate theory for the dynamical stabilization, through the
introduction of a massless scalar field in the bulk, which interacts with the
branes. We find exact static solutions for the metric and scalar field in the
bulk and demonstrate that the inter-brane distance is determined by the
parameters of scalar field-brane interactions. However, these solutions are
always accompanied by a correlation between the bulk cosmological constant, the
brane self-energies and the interaction terms of the scalar field with the
branes and thus cannot be considered as candidates for the phenomenologically
viable stabilized geometry. We find that the aforementioned correlation cannot
be avoided even in the case of a single-brane solution with positive
self-energy where the fifth dimension ends on a singularity.


title: The Diffractive Quantum Limits of Particle Colliders

abstract:
  Quantum Mechanics places limits on achievable transverse beam spot sizes of
particle accelerators. We estimate this limit for a linear collider to be
\Delta x > \hbar c f/E\delta_0 where f is the final focal length, E the beam
energy, and \delta_0 the intrinsic transverse Gaussian width of the electron
wave-function. \delta_0 is determined in the phase space damping rings, and we
find \delta_0 \approx \sqrt{\hbar c /eB} where B is the typical wiggler
magnetic field strength in this system. For the NLC \delta_0 = 25 nm, and
\Delta x = 0.06 nm, about two orders of magnitude smaller than the design goal.
We can recover a crude estimate of the classical result when we include
radiative relaxation effects. We also consider a synchrotron and obtain \Delta
x > \sqrt{\hbar c f/E} = O(1.0) nm. We discuss formulation of quantum beam
optics relevant to these issues.


title: J/Psi suppression in an expanding equilibrium hadron gas

abstract:
  We consider an ideal gas of massive hadrons in thermal and chemical
equilibrium. The finite-size gas expands longitudinally in accordance with
Bjorken law. Also the transverse expansion in a form of the rarefaction wave is
considered. We show that J/Psi suppression in such an environment, when
combined with the disintegration in nuclear matter, agrees qualitatively well
with NA38 and NA50 data.


title: Supersymmetry Phenomenology

abstract:
  This is a very pedagogical review of supersymmetry phenomenology, given at
ICTP Summer School in 1999, aimed mostly at students who had never studied
supersymmetry before. It starts with an analogy that the reason why
supersymmetry is needed is similar to the reason why the positron exists. It
introduces the construction of supersymmetric Lagrangians in a practical way.
The low-energy constraints, renormalization-group analyses, collider
phenomenology, and frameworks of mediating supersymmetry breaking are briefly
discussed.


title:
Effects of a dynamical role for exchanged quarks and nuclear gluons in
  nuclei: multinucleon correlations in deep-inelastic lepton scattering

abstract:
  It is shown that new data from the HERMES collaboration, as well as all of
the earlier improved data from experiments concerning the EMC effect and
shadowing in deep-inelastic scattering of leptons from nuclei, provide strong
evidence for an explicit dynamical role played by exchanged quarks and nuclear
gluons in the basic, tightly-bound systems of three and four nucleons, He3 and
He4. This opens the way for specific quark-gluon dynamics instigating
multinucleon correlations in nuclei.


title:
An updated analysis of eps'/eps in the standard model with hadronic
  matrix elements from the chiral quark model

abstract:
  We discuss the theoretical and experimental status of the CP violating ratio
eps'/eps. We revise our 1997 standard-model estimate-based on hadronic matrix
elements computed in the chiral quark model up to O(p^4) in the chiral
expansion-by including an improved statistical analysis of the uncertainties
and updated determination of the Cabibbo-Kobayashi-Maskawa elements and other
short-distance parameters. Using normal distributions for the experimental
input data we find Re eps'/eps = (2.2 \pm 0.8) x 10^{-3}, whereas a flat
scanning gives 0.9 x 10^{-3} < Re eps'/eps < 4.8 x 10^{-3}. Both results are in
agreement with the current experimental data. The key element in our estimate
is, as before, the fit of the Delta I=1/2 rule, which allows us to absorb most
of the theoretical uncertainties in the determination of the model-dependent
parameters in the hadronic matrix elements. Our semi-phenomenological approach
leads to numerical stability against variations of the renormalization scale
and scheme dependence of the short- and long-distance components. The same
dynamical mechanism at work in the selection rule also explains the larger
value obtained for \ratio with respect to other estimates. A coherent picture
of K -> pi pi decays is thus provided.


title: Estimating eps'/eps in the standard model independently of Im \lambda_t

abstract:
  The CP-violating parameter eps'/eps is estimated in a novel way by including
the explicit computation of eps in the ratio as opposed to the usual procedure
of taking its value from the experiments. This approach has the advantage of
being independent from the determination of the CKM parameters Im \lambda_t and
of showing more directly the dependence on the long-distance parameters. The
matrix elements are taken from the chiral quark model approach, the parameters
of which have been recently determined by an updated fit of the CP-conserving
amplitudes entering the \Delta I=1/2 rule. By taking a normal distribution for
the experimental inputs and a flat one for the theoretical uncertainties, it is
found that eps '/eps = (2.5 \pm 0.9) \times 10^{-3} in agreement with the
current experimental data. A more conservative estimate 0.9 x 10^{-3} <
eps'/eps < 5.8 x 10^{-3} is found by considering the smallest and the largest
values obtained by taking a flat distribution for all inputs.


title: Double inflation in supergravity and the primordial black hole formation

abstract:
  We study a double inflation model (a hybrid inflation + a new inflation) in
supergravity and discuss the formation of primordial black holes (PBHs) with
mass \sim 10^{-20}-10^{5}M_{\odot}. We find that in a wide range of parameter
space, we obtain PBHs which amount to \Omega \simeq 1, i.e., PBH dark matter.
Also, we find a set of inflation parameters which produces PBHs evaporating
now. Those PBHs may be responsible for antiproton fluxes observed by the BESS
experiment.


title: Improved determination of b quark mass from spectroscopy

abstract:
  Using recently evaluated contributions (including a novel one calculated
here), we 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. These values are
accurate including, respectively,
  $O(\alpha_s^5\log\alpha_s)$ and $O(\alpha_s^3)$ corrections and, in both
cases, leading orders in the ratio $m_c^2/m_b^2$.


title:
Double Higgs production at TeV Colliders in the Minimal Supersymmetric
  Standard Model

abstract:
  The reconstruction of the Higgs potential in the Minimal Supersymmetric
Standard Model (MSSM) requires the measurement of the trilinear Higgs
self-couplings. The `double Higgs production' subgroup has been investigating
the possibility of detecting signatures of processes carrying a dependence on
these vertices at the Large Hadron Collider (LHC) and future Linear Colliders
(LCs). As reference reactions, we have chosen $gg\to hh$ and $e^+e^-\to h h Z$,
respectively, where $h$ is the lightest of the MSSM Higgs bosons. In both
cases, the $Hhh$ interaction is involved. For $m_H>2m_h$, the two reactions are
resonant in the $H\to hh$ mode, providing cross sections which are detectable
at both accelerators and strongly sensitive to the strength of the trilinear
coupling involved. We explore this mass regime of the MSSM in the $h\to b\bar
b$ decay channel, also accounting for irreducible background effects.


title: Fermion propagator in a nontrivial background field

abstract:
  We study the fermion propagator in a spatially varying classical background
field, and show that, contrary to common wisdom, it may get nontrivial gradient
corrections already at the first order in derivative expansion. This occurs
whenever the fermion self-energy acquires a spatially (or temporally) varying
pseudoscalar term, a simple example of which is given by a complex mass term
m(x)= m_R + i gamma_5 m_I. Such effective mass terms arise for example in
extensions of the Standard Model during the electroweak transition, and they
are crucial in providing the CP-violation necessary for electroweak
baryogenesis.

categories: hep-ph astro-ph cond-mat.stat-mech hep-th nucl-th physics.plasm-ph


title: Heavy quark mass expansion and intrinsic charm in light hadrons

abstract:
  We review the technique of heavy quark mass expansion of various operators
made of heavy quark fields using a semiclassical approximation. It corresponds
to an operator product expansion in the form of series in the inverse heavy
quark mass. This technique applied recently to the axial current is used to
estimate the charm content of the \eta, \eta' mesons and the intrinsic charm
contribution to the proton spin. The derivation of heavy quark mass expansion
for Qbar \gamma_5 Q is given here in detail and the expansions of the scalar,
vector and tensor current and of a contribution to the energy-momentum tensor
are presented as well. The obtained results are used to estimate the intrinsic
charm contribution to various observables.


title:
Nonperturbative Gluon Radiation and Energy Dependence of Elastic
  Scattering

abstract:
  The energy dependence of the total hadronic cross sections is caused by gluon
bremsstrahlung which we treat nonperturbatively. It is located at small
transverse distances about 0.3 fm from the valence quarks. The cross section of
gluon radiation is predicted to exponentiate and rise with energy as s^{\Delta}
with \Delta=0.17 +/- 0.01. The total cross section also includes a large energy
independent Born term which corresponds to no gluon radiation. The calculated
total cross section and the slope of elastic scattering are in good agreement
with the data.


title: Seesaw mechanism, quark-lepton symmetry and Majorana phases

abstract:
  A previous short analysis of the seesaw mechanism, based on quark-lepton
symmetry, experimental data and hierarchical neutrino spectrum, is enlarged to
include small but not zero U_{e3}, inverted mass hierarchy, and the qualitative
effect of Majorana phases. The structure of the heavy neutrino mass matrix
obtained in several cases is discussed. We find two leading forms for this
matrix. One is diagonal and stands at the unification scale or above. The other
is off-diagonal and stands at the intermediate scale.


title:
Angular Distribution of Charming B -> V V Decays and Time Evolution
  Effects

abstract:
  Angular distributions of a B meson decaying into two vector mesons are
discussed with emphasis on time evolution effects on the complete set of
amplitude bilinears. Time integrated quantities are suggested to observe
substantial CP violation in decays with charm quarks in the final state
particles. Relations among the nine observables at $t=0$ are found to be useful
for a consistency check of experimentally extracted quantities. Numerical
estimates of the nine observables are made using form factor models and the
assumption of the factorization hypothesis. Branching ratio asymmetries for
B_u^+ -> D^{*+} \bar D^{*0} and B_d -> D^{*+} D^{*-} can be as large as -3% and
-4%, respectively.


title:
Anisotropy of Dynamical Fluctuations as a Probe for Soft and Hard
  Processes in High Energy Collisions

abstract:
  It is shown using Lund Monte Carlo that, unlike the average properties of the
hadronic system inside jets, the anisotropy of dynamical fluctuations in these
systems changes abruptly with the variation of the cut parameter $y_cut$. A
transition point exists, where the dynamical fluctuations in the hadronic
system inside jet behave like those in soft hadronic collisions. Thus the
anisotropy property of the dynamical fluctuations can serve as a probe for the
soft and hard processes in high energy collisions.


title:
Impact of Physical Principles at Very High Energy Scales on the
  Superparticle Mass Spectrum

abstract:
  We survey a variety of proposals for new physics at high scales that serve to
relate the multitude of soft supersymmetry breaking parameters of the MSSM. We
focus on models where the new physics results in non-universal soft parameters,
in sharp contrast with the usually assumed mSUGRA framework. These include {\it
i}) SU(5) and SO(10) grand unified (GUT) models, {\it ii}) the MSSM plus a
right-handed neutrino, {\it iii}) models with effective supersymmetry, {\it
iv}) models with anomaly-mediated SUSY breaking and gaugino mediated SUSY
breaking, {\it v}) models with non-universal soft terms due to string dynamics,
and {\it vi}) models based on $M$-theory. We outline the physics behind these
models, point out some distinctive features of the weak scale sparticle
spectrum, and allude to implications for collider experiments. To facilitate
future studies, for each of these scenarios, we describe how collider events
can be generated using the program ISAJET. Our hope is that detailed studies of
a variety of alternatives will help point to the physics underlying SUSY
breaking and how this is mediated to the observable sector, once sparticles are
discovered and their properties measured.


title: New Formulation of Matter Effects on Neutrino Mixing and CP Violation

abstract:
  Within the framework of three lepton families we have derived an exact and
compact formula to describe the matter effect on neutrino mixing and CP
violation. This model- and parametrization-independent result can be
particularly useful for recasting the fundamental lepton flavor mixing matrix
from a variety of long-baseline neutrino experiments.


title:
Field strength correlators in the instanton gas: The importance of the
  two-instanton contribution

abstract:
  The field strength correlators at zero temperature are semi-classically
evaluated fitting the random instanton liquid model to lattice data for
quenched SU(3) lattice gauge theory. We restrict ourselves to the lowest order
in an instanton density expansion necessary to explain the difference between
transverse and longitudinal correlation functions. In the instanton-instanton
and instanton-antiinstanton contributions the Schwinger line factors neglected
in a previous analysis are numerically taken into account in a weighted Monte
Carlo evaluation. This leads to different estimates for instanton size and
density. A reasonable description of the correlators within the intermediate
range from 0.4 fm to 1 fm is obtained.


title: Neutrino Mixing and Maximal CP Violation

abstract:
  We propose a phenomenological model of lepton mixing and CP violation based
on the flavor democracy of charge leptons and the mass degeneracy of neutrinos.
A nearly bi-maximal flavor mixing pattern, which is favored by current data on
atmospheric and solar neutrino oscillations, emerges naturally from this model
after explicit symmetry breaking. The rephasing-invariant strength of CP or T
violation can be as large as one percent, leading to significant probability
asymmetries between \nu_\mu \to \nu_e and \bar{\nu}_\mu \to \bar{\nu}_e (or
\nu_e \to \nu_\mu) transitions in the long-baseline neutrino experiments. The
possible matter effects on CP- and T-violating asymmetries are also taken into
account.


title: Four-fermion production in electron-positron collisions with NEXTCALIBUR

abstract:
  We introduce a new, fully massive, Monte Carlo program to compute all
four-fermion processes in electron-positron collisions, including Higgs
production. We outline our strategy for the matrix element evaluation, the
phase space generation and the implementation of the leading higher order
effects, and show, where available, comparisons with existing results.


title: The QCD Potential at $O(1/m)$

abstract:
  Within an effective field theory framework, we obtain an expression for the
next-to-leading term in the $1/m$ expansion of the singlet $Q{\bar Q}$ QCD
potential in terms of Wilson loops, which holds beyond perturbation theory. The
ambiguities in the definition of the QCD potential beyond leading order in
$1/m$ are discussed and a specific expression for the $1/m$ potential is given.
We explicitly evaluate this expression at one loop and compare the outcome with
the existing perturbative results. On general grounds we show that for quenched
QED and fully Abelian-like models this expression exactly vanishes.


title: A Path Integral Approach to Inclusive Processes

abstract:
  The single-particle inclusive differential cross-section for a reaction
$a+b\to c+X$ is written as the imaginary part of a correlation function in a
for ward scattering amplitude for $a+b\to a+b$ in a modified effective theory.
In this modified theory the interaction Hamiltonian $\tilde H_I$ equals $H_I$
in the original theory up to a certain time. Then there is a sign change and
$\tilde H_I$ becomes nonlocal. This is worked out in detail for scalar field
models and for QED plus the abelian gluon model. A suitable path integral for
direct calculations of inclusive cross sections is presented.


title: The Nucleon Anapole Moment and Parity-Violating ep Scattering

abstract:
  Parity-violating (PV) interactions among quarks in the nucleon induce a PV
$\gamma NN$ coupling, or anapole moment (AM). We compute electroweak
gauge-independent contributions to the AM through ${\cal O}(1/\lamchis)$ in
chiral perturbation theory. We estimate short-distance PV effects using
resonance saturation. The AM contributions to PV electron-proton scattering
slightly enhance the axial vector radiative corrections, R_A^p, over the scale
implied by the Standard Model when weak quark-quark interactions are neglected.
We estimate the theoretical uncertainty associated with the AM contributions to
R_A^p to be large, and discuss the implications for the interpretation PV of ep
scattering.


title:
Exploiting Spin Correlations in Neutralino Production and Decay with
  Polarized e^- and e^+ Beams

abstract:
  We study the production process e^+ e^- -> chi^0_1 chi^0_2 and the subsequent
decay chi^0_2 -> chi^0_1 l^+ l^- with polarized e^+ and e^- beams, including
the spin correlations between production and decay. We work out the advantages
of polarizing both beams. We study in detail the angular distribution and the
forward--backward asymmetry of the decay lepton as well as the opening angle
distribution between the decay leptons. We investigate the dependence on the
masses of tilde{e}_L and tilde{e}_R and on the mixing character of the
neutralinos. In particular we study the dependence on the gaugino mass
parameter M_1.


title: Theory of rare kaon decays

abstract:
  We review some recent theoretical results on rare kaon decays. Particular
attention is devoted to find Standard Model tests. This is theoretically easy
in $K\to \pi \nu \bar{\nu}$, while a careful study of the long distance
contributions is needed for $K_{L}\to \pi ^{0}e% \bar{e}$, $K_{L}\to \mu
\bar{\mu}$ and $K\to \pi \pi \gamma$


title: TeV scale gravity, mirror universe, and ... dinosaurs

abstract:
  This is somewhat extended version of the talk given at the Gran Sasso Summer
Institute: Massive Neutrinos in Physics and Astrophysics. It describes general
ideas about mirror world, extra spatial dimensions and dinosaur extinction.
Some suggestions are made how these seemingly different things can be related
to each other.


title: Electroweak baryogenesis from preheating

abstract:
  The origin of the matter-antimatter asymmetry remains one of the most
fundamental problems of cosmology. In this talk I present a novel scenario for
baryogenesis at the electroweak scale, without the need for a first order phase
transition. It is based on the out of equilibrium resonant production of long
wavelength Higgs and gauge configurations, at the end of a period of inflation,
which induces a large rate of sphaleron transitions, before thermalization at a
temperature below critical.


title: Cosmic Neutrinos and New Physics beyond the Electroweak Scale

abstract:
  New physics beyond the electroweak scale may increase weak interaction cross
sections beyond the Standard Model predictions. Such cross sections can be
expected within theories that solve the hierarchy problem of known interactions
with a unification scale in the TeV range. We derive constraints on these cross
sections from the flux of neutrinos expected from cosmic ray interactions with
the microwave background and the non-observation of horizontal air showers. We
also discuss how this limit can be improved by upcoming cosmic ray and neutrino
experiments, and how the energy dependence of the new interactions can be
probed by these experiments.


title: The Higgs Working Group: Summary Report

abstract:
  Report of the Higgs working group for the Workshop "Physics at TeV
Colliders", Les Houches, France 8-18 June 1999. It contains 6 separate
sections:
  1. Measuring Higgs boson couplings at the LHC.
  2. Higgs boson production at hadron colliders at NLO.
  3. Signatures of Heavy Charged Higgs Bosons at the LHC.
  4. Light stop effects and Higgs boson searches at the LHC.
  5. Double Higgs production at TeV Colliders in the MSSM.
  6. Programs and Tools for Higgs Bosons.


title: Atomic Parity Violation, Leptoquarks, and Contact Interactions

abstract:
  The recent measurement of atomic parity violation in cesium atoms shows a
$2.3\sigma$ deviation from the standard model prediction. We show that such an
effect can be explained by four-fermion contact interactions with specific
chiralities or by scalar leptoquarks which couple to the left-handed quarks.
For a coupling of electromagnetic strength, the leptoquark mass is inferred to
be 1.1 to 1.3 TeV. We also show that these solutions are consistent with all
other low-energy and high-energy neutral-current data.


title:
SU(3) Flavor Symmetry and CP Violating Rate Differences for Charmless
  $B\to P V$ Decays

abstract:
  We derive several relations between CP violating rate differences
$\Delta(B\to PV) = \Gamma(B\to PV) - \Gamma(\bar B \to \bar P \bar V)$ for
charmless $B\to P V$ decays in the Standard Model using SU(3) flavor symmetry.
It is found that although the relations between branching ratios of $\Delta S =
0$ and $\Delta S = -1$ processes are complicated, there are simple relations
independent of hadronic models between some of the $\Delta S =0$ and $\Delta S
= -1$ rate differences due to the unitarity property of the Kobayashi-Maskawa
matrix, such as $ \Delta(B\to \pi^+ \rho^-) = -\Delta(B\to \pi^+ K^{*-})$,
$\Delta(B\to \pi^- \rho^+) = - \Delta(K^- \rho^+)$. SU(3) breaking effects are
also estimated using factorization approximation. These relations can be tested
at B factories in the near future.


title:
|V_ub| and |V_cb|, Charm Counting and Lifetime Differences in Inclusive
  Bottom Hadron Decays

abstract:
  Inclusive bottom hadron decays are analyzed based on the heavy quark
effective field theory (HQEFT). Special attentions in this paper are paid to
the b\to u transitions and nonspectator effects. As a consequence, the CKM
quark mixing matrix elements |V_ub| and |V_cb| are reliably extracted from the
inclusive semileptonic decays B\to X_u e \nu and B\to X_c e \nu. Various
observables, such as the semileptonic branch ratio B_SL, the lifetime
differences among B^-, B^0, B_s and \Lambda_b hadrons, the charm counting n_c,
are predicted and found to be consistent with the present experimental data.


title:
Low-Scale Anomalous U(1) and Decoupling Solution to Supersymmetric
  Flavor Problem

abstract:
  Supersymmetric standard models where the ultraviolet cut-off scale is only a
few orders of magnitude higher than the electroweak scale are considered.
Phenomenological consequences of this class of models are expected to be very
different from, for example, the conventional supergravity scenario. We apply
this idea to a model with an anomalous U(1) gauge group and construct a viable
model in which some difficulties of the decoupling solution to the
supersymmetric flavor problem are ameliorated.


title:
Implications of Anomalous U(1) Symmetry in Unified Models: the Flipped
  SU(5) x U(1) Paradigm

abstract:
  A generic feature of string-derived models is the appearance of an anomalous
Abelian U(1)_A symmetry which, among other properties, constrains the Yukawa
couplings and distinguishes the three families from each other. In this paper,
we discuss in a model-independent way the general constraints imposed by such a
U(1)_A symmetry on fermion masses, R-violating couplings and proton-decay
operators in a generic flipped SU(5) x U(1)' model. We construct all possible
viable fermion mass textures and give various examples of effective low-energy
models which are distinguished from each other by their different predictions
for B-, L- and R-violating effects. We pay particular attention to predictions
for neutrino masses, in the light of the recent Super-Kamiokande data.


title:
Bilinear R-parity violating SUSY: Neutrinoless double beta decay in the
  light of solar and atmospheric neutrino data

abstract:
  Neutrinoless double beta ($\znbb$) decay is considered within bilinear
R-parity breaking supersymmetry, including the full one-loop corrections to the
neutrino-neutralino mass matrix. Expected rates for $\znbb$ decay in this model
are discussed in light of recent atmospheric and solar neutrino data. We
conclude that (a) tree-level calculations for $\znbb$ decay within the bilinear
model are not reliable in the range of parameters preferred by current solar
and atmospheric neutrino problems. And (b) if the solar and atmospheric
neutrino problems are to be solved within bilinear R-parity violating SUSY the
expected rates for $\znbb$ decay are very low; the effective Majorana neutrino
mass at most 0.01 eV and typical values being one order of magnitude lower.
Observing $\znbb$ decay in the next round of experiments therefore would rule
out the bilinear R-parity violating supersymmetric model as an explanation for
solar and atmospheric neutrino oscillations, as well as any hierarchical scheme
for neutrino masses, unless new neutrino interactions are present.


title: Radiative Rare Kaon Decays

abstract:
  We review some recent theoretical results on radiative rare kaon decays.
Particular attention is devoted to the channels $K\to \pi l\bar{% l}$ and $K\to
\pi \pi \gamma$, where we are (or might be) able to extract the short distance
contributions. This is achieved by a careful study of the long distance part.
We study also CP violating observables, which are sensitive also to extensions
of the SM. As byproduct, we discuss interesting chiral tests.


title:
Calculating three-loop diagrams in Heavy Quark Effective Theory with
  integration-by-parts recurrence relations

abstract:
  An algorithm for calculation of three-loop propagator diagrams in HQET, based
on integration-by-parts recurrence relations, is constructed and implemented as
a REDUCE package Grinder, and in Axiom.


title:
Features of particle multiplicities and strangeness production in
  central heavy ion collisions between 1.7A and 158A GeV/c

abstract:
  A systematic study is performed of fully integrated particle multiplicities
in central Au-Au and Pb-Pb collisions at beam momenta of 1.7A GeV, 11.6A GeV
(Au-Au) and 158$A$ GeV (Pb-Pb) by using a statistical-thermal model. The close
similarity of the colliding systems makes it possible to study heavy ion
collisions under definite initial conditions over a range of centre-of-mass
energies covering more than one order of magnitude. In order to further study
the behaviour of strangeness production, an updated study of Si-Au collisions
at 14.6A GeV is also presented. The data analysis has been performed with two
completely independent numerical algorithms giving closely consistent results.
We conclude that a thermal model description of particle multiplicities, with
additional strangeness suppression, is possible for each energy. The degree of
chemical equilibrium of strange particles and the relative production of
strange quarks with respect to u and d quarks are higher than in e+e-, pp and
ppbar collisions at comparable and even at lower energies. The behaviour of
strangeness production as a function of centre-of-mass energy and colliding
system is presented and discussed. The average energy per hadron in the
comoving frame is close to 1 GeV per hadron despite the fact that the energy
increases more than 10-fold.


title:
Transversity Distribution and Polarized Fragmentation Function from
  Semi-inclusive Pion Electroproduction

abstract:
  A method is discussed to determine the hitherto unknown u-quark transversity
distribution from a planned HERMES measurement of a single-spin asymmetry in
semi-inclusive pion electroproduction off a transversely polarized target.
Assuming u-quark dominance, the measurement yields the shapes of the
transversity distribution and of the ratio of a polarized and the unpolarized
u-quark fragmentation functions. The unknown relative normalization can be
obtained by identifying the transversity distribution with the well-known
helicity distribution at large x. The systematic uncertainty of the method is
dominated by the assumption of u-quark dominance.


title:
Axial anomaly, vector meson dominance and $\pi^0 \to \gamma \gamma$ at
  finite temperature

abstract:
  A thermal Finite Energy QCD Sum Rule is used to determine the temperature
behaviour of the $\omega \rho \pi$ strong coupling. This coupling decreases
with increasing $T$ and vanishes at the critical temperature, a likely signal
for quark deconfinement. This is then used in the Vector Meson Dominance (VMD)
expression for the $\pi^0 \to \gamma \gamma$ amplitude, which is also found to
vanish at the critical temperature, as expected. This result supports the
validity of VMD at $T \neq 0$. However, if VMD would not hold at finite
temperature, then there is no prediction for the $\pi^0 \to \gamma \gamma$
amplitude.


title:
Anomalous processes at high temperature and density in a 2-dimensional
  linear $\sigma$ model

abstract:
  We use the 2-dimensional $\sigma$ model as a toy model to study the behavior
of anomalous amplitudes in the limit where the constituent quark mass is small.
Symmetry arguments tell that the $\pi^o\to\gamma$ amplitude should vanish if
$m\to 0$, but we show that this conclusion is spoiled by infrared
singularities. When a proper regularization (resummation of a thermal mass, for
instance) is taken into account, this amplitude vanishes as expected. We also
study the amplitude $\pi^o\sigma\to\gamma$ and show that it does not vanish in
the same limit.


title: Scaling and Duality in Semi-exclusive Processes

abstract:
  We discuss extending scaling and duality studies to semi-exclusive processes.
We show that semi-exclusive hard pion photoproduction should exhibit scaling
behavior in kinematic regions where the photon and pion both interact directly
with the same quark. We show that such kinematic regions exist. We also show
that the constancy with changing momentum transfer of the resonance
peak/scaling curve ratio, familiar for many resonances in deep inelastic
scattering, is also expected in the semi-exclusive case.


title: A New Source for Electroweak Baryogenesis in the MSSM

abstract:
  One of the most experimentally testable explanations for the origin of the
baryon asymmetry of the universe is that it was created during the electroweak
phase transition, in the minimal supersymmetric standard model. Previous
efforts have focused on the current for the difference of the two Higgsino
fields, $H_1-H_2$, as the source of biasing sphalerons to create the baryon
asymmetry. We point out that the current for the orthogonal linear combination,
$H_1+H_2$, is larger by several orders of magnitude. Although this increases
the efficiency of electroweak baryogenesis, we nevertheless find that large
CP-violating angles $\ge 0.15$ are required to get a large enough baryon
asymmetry.


title: Sources for Electroweak Baryogenesis

abstract:
  I review a computation of the baryon asymmetry arising from a first order
electroweak phase transition in the Minimal Supersymmetric Standard model by
classical force mechanism (CFM). I focus on CP violation provided by the
charginos and show that it is the usually neglected sum of the two Higgsino
fields, H_1+H_2, which gives a larger contribution to the baryon asymmetry than
does the combination H_1-H_2. In fact, the latter contribution is exactly zero
in CFM, because it is associated with a phase transformation of the fields.
Baryogenesis is found to be most effective in MSSM CFM when only $\tilde t_R$
is light, which lends independent support for the "light stop scenario", and it
remains viable for CP-violating phases as small as \delta_\mu \sim {\it few}
\times 10^{-3}.


title: Production of high-energy gravitinos during preheating

abstract:
  We present a new technique for the calculation of helicity $\pm 1/2$
gravitino production during preheating. It is based on the equivalence between
goldstinos and helicity $\pm 1/2$ gravitinos at high energies. The problem is
thus reduced to the standard (Majorana) fermion production after inflation.
Comparison with the results obtained in the unitary gauge is also presented.


title: Continuous emission versus freeze-out via HBT

abstract:
  The effect of the continuous emission hypothesis on the two-pion
Bose-Einstein correlation function is discussed and compared with the
corresponding results based on the usual freeze-out. Sizeable differences in
the correlation function appear in these different descriptions of the
decoupling process. This means that, when extracting properties of the hot
matter formed in high-energy heavy-ion collisions from the data, completely
different conclusions may be reached according to the description of the
particle emission process adopted.


title: Vacuum Polarisation Tensors in Constant Electromagnetic Fields: Part II

abstract:
  In the second part of this series we apply the ``string-inspired'' technique
to the calculation of one-loop amplitudes involving both vectors and
axialvectors, as well as a general constant electromagnetic background field.
The vector-axialvector two-point function in a constant field is calculated
explicitly.


title: A Note on Anomaly Matching for Finite Density QCD

abstract:
  We note that the QCD phases at large finite density respect 't Hooft anomaly
matching conditions. Specifically the spectrum of the light excitations
possesses the correct quantum numbers required to obey global anomaly
constraints. We argue that 't Hooft constraints can be used at finite density
along with non perturbative methods to help selecting the correct phase.


title: Minijets and Transverse Energy Flow in High Energy Collisions

abstract:
  When studying the production of minijets and transverse energy flow in high
energy hadron-hadron or nucleus-nucleus collisions, two essential points have
to be taken into account. First, one has to account for the virtuality of the
colliding partons and secondly, it is important to avoid double counting, when
many links in a parton chain can be interpreted as the momentum transfer in a
hard subcollision. The Linked Dipole Chain model, introduced for low-x DIS, is
particularly suitable for a study of these problems. It describes (mini)jet
production in a kT-factorizing formalism, which includes all links in a parton
chain on an equal footing, avoiding double counting. In a ``naive'' calculation
based on integrated structure functions, the cross section blows up for small
pT, which makes it necessary to introduce a soft cutoff. In our approach we
find a dynamical suppression at low pT, which makes it possible to extrapolate
to higher energies and make more reliable predictions for RHIC and LHC.


abstract:
  Lepton flavor violation in the Randall-Sundrum model with bulk neutrinos is
considered. Grossman and Neubert recently proposed that the existence of tiny
neutrino masses and large mixing could be explained by the presence of the bulk
neutrinos in the Randall-Sundrum background. Since the zero mode wave functions
of the bulk neutrinos are localized on Planck brane, the Dirac Yukawa couplings
on our brane are exponentially suppressed enough to generate tiny neutrino
masses. However, the existence of Kaluza-Klein modes of these bulk neutrinos
enhance lepton flavor violating processes such as $\mu \to e \gamma$, from
which lower bounds on their masses can be derived. We find that the first KK
mode must be heavier than 25 TeV if all the neutrino Yukawa couplings are of
order unity, which requires a fine-tuning for the Higgs mass parameter.


title: Effects of flavor conserving CP violating phases in SUSY models

abstract:
  I summarize our recent works on the effects of flavor conserving CP violating
phases in SUSY models on $B$ and $K$ phenomenology.


title: Self-energy O(alpha^2) correction to the positronium decay rate

abstract:
  Self-energy corrections of order O(alpha^2) to the parapositronium and
orthopositronium decay rates are calculated. Numerical values of the
corresponding coefficients are B_p=-3.74, B_o=2.02.


title: The geometry of atmospheric neutrino production

abstract:
  The zenith angle distributions of atmospheric neutrinos are determined by the
possible presence of neutrino oscillations and the combination of three most
important contributions: (1) geomagnetic effects on the primary cosmic rays,
that suppress the primary flux in the Earth's magnetic equatorial region, (2)
the zenith angle dependence of the neutrino yields, due to the fact that
inclined showers produce more neutrinos, and (3) geometrical effects due to the
spherical shell geometry of the neutrino production volume. The last effect has
been recognized only recently and results in an important enhancement of the
flux of sub--GeV neutrinos for horizontal directions. In this work we discuss
the geometrical effect and its relevance in the interpretation of the
atmospheric neutrino data.


title: Sigma-term physics

abstract:
  We consider sigma-terms in $\pi\pi$, $\pi N$ and $K N$ scattering. While the
state of the art in $\pi\pi$ is in principle crystal clear, the kaon-nucleon
case is largely unexplored. The pion-nucleon system is in-between. We propose a
list of topics to be investigated in kaon-nucleon scattering, in order to make
optimal use of the precision data expected from DEAR.


title: Neutrino Exotica in the Skew E_6 Left-Right Model

abstract:
  With the particle content of the 27 representation of E_6, a skew left-right
supersymmetric gauge model was proposed many years ago, with a variety of
interesting phenomenological implications. The neutrino sector of this model
offers a natural framework for obtaining small Majorana masses for nu_e, nu_mu,
and nu_tau, with the added bonus of accommodating 2 light sterile neutrinos.


title: Q-ball formation in the gravity-mediated SUSY breaking scenario

abstract:
  We study the formation of Q-balls which are made of flat directions that
appear in the supersymmetric extension of the standard model in the context of
gravity-mediated supersymmetry breaking. The full non-linear calculations for
the dynamics of the complex scalar field are made. Since the scalar potential
in this model is flatter than \phi^2, we have found that fluctuations develop
and go non-linear to form non-topological solitons, Q-balls. The size of a
Q-ball is determined by the most amplified mode, which is completely determined
by the model parameters. On the other hand, the charge of Q-balls depends
linearly on the initial charge density of the Affleck-Dine (AD) field. Almost
all the charges are absorbed into Q-balls, and only a tiny fraction of the
charges is carried by a relic AD field. It may lead to some constraints on the
baryogenesis and/or parameters in the particle theory. The peculiarity of
gravity-mediation is the moving Q-balls. This results in collisions between
Q-balls. It may increase the charge of Q-balls, and change its fate.


title: Natural Effective Supersymmetry

abstract:
  Much heavier sfermions of the first-two generations than the other
superparticles provide a natural explanation for the flavor and CP problems in
the supersymmetric standard model (SUSY SM). However, the heavy sfermions may
drive the mass squareds for the light third generation sfermions to be negative
through two-loop renormalization group (RG) equations, breaking color and
charge. Introducing extra matters to the SUSY SM, it is possible to construct
models where the sfermion masses are RG invariant at the two-loop level in the
limit of vanishing gaugino-mass and Yukawa-coupling contributions. We calculate
the finite corrections to the light sfermion masses at the two-loop level in
the models. We find that the finite corrections to the light-squark mass
squareds are negative and can be less than (0.3-1)% of the heavy-squark mass
squareds, depending on the number and the parameters of the extra matters. We
also discuss whether such models realized by the U(1)_X gauge interaction at
the GUT scale can satisfy the constraints from \Delta m_K and \epsilon_K
naturally. When both the left- and right-handed down-type squarks of the
first-two generations have common U(1)_X charges, the supersymmetric
contributions to \Delta m_K and \epsilon_K are sufficiently suppressed without
spoiling naturalness, even if the flavor-violating supergravity contributions
to the sfermion mass matrices are included. When only the right-handed squarks
of the first-two generations have a common U(1)_X charge, we can still satisfy
the constraint from \Delta m_K naturally, but evading the bound from \epsilon_K
requires the CP phase smaller than 10^{-2}.


title:
Loop Corrections to the Neutral Higgs Boson Sector of the MSSM with
  Explicit CP Violation

abstract:
  We compute one-loop corrections to the mass matrix of the neutral Higgs
bosons of the Minimal Supersymmetric Standard Model with explicit CP violation.
We use the effective potential method, allowing for arbitrary splitting between
squark masses. We include terms O(g^2 h^2), where g and h stand for electroweak
gauge and Yukawa couplings, respectively. Leading two-loop corrections are
taken into account by means of appropriately defined running quark masses.


title: Radiative corrections to the decay $H^+ \to W^+ A^0$

abstract:
  Full one-loop electroweak corrections to the on-shell decay $H^+ \to W^+A^0$
are computed in the framework of models with two Higgs doublets (THDM). Such a
decay may be dominant for $H^{\pm}$ over a wide range of parameter space
relevant at present and future colliders. We show that the corrections may
approach 40% and in particular are sensitive to $\lambda_5$, which parametrizes
the discrete symmetry breaking term. We suggest that a measurement of the
branching ratio of $H^+ \to W^+A^0$ may offer a possibility of measuring the
magnitude of $\lambda_5$.


title: Right-Handed Vector V and Axial A Couplings in Weak Interactions

abstract:
  In this paper a scenario admitting the participation of right-handed vector V
and axial A couplings with the conservation of the left-handed standard (V, A)
couplings is considered. The research is based on the muon capture by proton.
We consider muon capture at the level of the Fermi theory (four-fermion point
interaction). Neutrinos are assumed to be massive and to be Dirac fermions. We
propose neutrino observables, it means transverse components of the neutrino
polarization, both T-odd and T-even. That would be a unique test verifying the
participation of the right-handed (V, A) couplings in muon capture. The effects
of the transverse neutrino polarization connected with the right-handed (V, A)
couplings may be of the order of 7%. Our considerations are model-independent.
We give the lower bound of 305 GeV on the mass of the right-handed gauge boson.
This limit is compatible with the current bounds on the mass of the
right-handed vector boson received from the weak interaction processes at low
energy.


title: Width effects in slepton production e+ e- --> ~mu_R ~mu_R

abstract:
  A case study will be presented to investigate width effects in the precise
determination of slepton masses at the e+e- TESLA Linear Collider.


title:
Self-consistent approximations: application to a quasiparticle
  description of the thermodynamic properties of relativistic plasmas

abstract:
  We generalize the concept of conserving,\Phi-derivable, approximations to
relativistic field theories. Treating the interaction field as a dynamical
degree of freedom, we derive the thermodynamical potential in terms of fully
dressed propagators, an approach which allows us to resolve the entropy of a
relativistic plasma into contributions from its interacting elementary
excitations. We illustrate the derivation for a hot QED plasma of massless
particles. We also discuss how the self-consistency of the treatment manifests
itself into relationships between the contributions from interaction and matter
fields.


title: Towards String Predictions

abstract:
  The aim of superstring phenomenology is to develop the tools and methodology
needed to confront string theory with experimental data. The first mandatory
task is to find string solutions which reproduce the observable data. The
subsequent goal is to extract potential signatures beyond the observable data.
Recently, by studying exact flat directions of non-Abelian singlet fields, we
demonstrated the existence of free fermionic heterotic-string models in which
the $SU(3)\times SU(2)\times U(1)_Y$-charged matter spectrum, just below the
string scale, consists solely of the MSSM spectrum. In this paper we study the
possibility that the exact flat directions leave a $U(1)_{Z^\prime}$ symmetry
unbroken at the Planck scale. We demonstrate in a specific example that such
unbroken $U(1)_{Z^\prime}$ is in general expected to be not of the GUT type but
of intrinsic stringy origin. We study its phenomenological characteristics and
the consequences in the case that $U(1)_{Z^\prime}$ remains unbroken down to
low energies. We suggest that observation in forthcoming colliders of a
$Z^\prime$, with universal couplings for the two light generations but
different couplings for the heavy generation may provide evidence for the
$Z_2\times Z_2$ orbifold which underlies the free fermionic models.


title: SNO: Predictions for Ten Measurable Quantities

abstract:
  We calculate the range of predicted values for 10 quantities that will be
measured by the Sudbury Neutrino Observatory (SNO). We use neutrino oscillation
solutions (vacuum and MSW; active and sterile neutrinos) that are globally
consistent with all available neutrino data and estimate realistic theoretical
and experimental uncertainties. The neutral current to charged current double
ratio is predicted to be more than 9 sigma from the no-oscillation solution for
all of the currently favored neutrino oscillation solutions. The best-fit
oscillation solutions predict a CC day-night rate difference between -0.1% and
+12.5% and a NC day-night difference < 0.01%. We present also the predicted
range for the first and the second moments of the charged current electron
recoil energy spectrum, the charged current, the neutral current, and the
neutrino-electron scattering rates, the seasonal dependence of the charged
current rate, and the double ratio of neutrino-electron scattering rate to
charged current rate.


title:
Constraint from Lamb Shift and Anomalous Magnetic Moment on Radiatively
  Induced Lorentz and CPT Violation in Quantum Electrodynamics

abstract:
  We investigate the precisely measured anomalous magnetic moment and Lamb
shift as tests for the possible existence of the radiatively induced Lorentz
and CPT violation effects in quantum electrodynamics. To this end we calculate
the one-loop vacuum polarization tensor and vertex radiative correction in
dimensional reduction and on-shell renormalization scheme. We explicitly show
how the Lorentz and CPT violation sector affects the anomalous magnetic moment
and Lamb shift. Remarkably, we find infrared divergences coming from Lorentz
and CPT violating term that do not cancel in physical cross sections. This
result appears to place stringent constraints on the type of Lorentz/CPT
violating terms that can be added to the QED Lagrangian.


title:
A note on spectator effects and quark-hadron duality in inclusive beauty
  decays

abstract:
  In this paper, we evaluate the expectation values of four-quark operators for
the inclusive beauty decays from the differences in the inclusive total decay
rates, assuming that the heavy quark expansion converges at $O(1/m^3)$. The
obtained expectation values yeilds the ratio $\tau(\Lambda_b)/\tau(B)$ close to
the experimental onee. We further point out that the quark-hadron duality
violation would be rather small allowing predictions of inclusive quantities.


title: Manifestaion of SUSY in B decays

abstract:
  SUSY effects on various flavor changing neutral current processes are
discussed in the minimal supergravity model and the SU(5) grand unified theory
with right-handed neutrino supermultiplets. In particular, in the latter case
the neutrino Yukawa coupling constants can be a source of the flavor mixing in
the right-handed-down-type-squark sector. It is shown that due to this mixing
the time-dependent CP asymmetry of radiative B decay can be as large as 30% and
the ratio of $B_s$-$\bar{B}_s$ mixing and $B_d$-$\bar{B}_d$ mixing deviates
from the prediction in the standard model and the minimal supergravity model
without the neutrino interaction.


title: The Cosmological Constant From The Viewpoint Of String Theory

abstract:
  The mystery of the cosmological constant is probably the most pressing
obstacle to significantly improving the models of elementary particle physics
derived from string theory. The problem arises because in the standard
framework of low energy physics, there appears to be no natural explanation for
vanishing or extreme smallness of the vacuum energy, while on the other hand it
is very difficult to modify this framework in a sensible way. In seeking to
resolve this problem, one naturally wonders if the real world can somehow be
interpreted in terms of a vacuum state with unbroken supersymmetry.


title:
Determination of equation of state of quark matter from $J/\psi$ and
  $\Upsilon$ suppression at RHIC and LHC

abstract:
  The long life-time of the quark-gluon plasma likely to be created in the
relativistic heavy ion collisions at RHIC and LHC energies renders it sensitive
to the details of the equation of state of the quark-matter. We show that the
$p_T$ dependence of the survival probability of the directly produced $J/\psi$
at RHIC energies and that of the directly produced $\Upsilon$ at LHC energies
is quite sensitive to the speed of sound in the quark matter, which relates the
pressure and the energy density of the plasma. The transverse expansion of the
plasma is shown to strongly affect the $J/\psi$ suppression at LHC energies.


title: Parameter counting for neutrino mixing

abstract:
  The content of physical massess, mixing angles and CP-violating phases in the
lepton sector of extended standard model, both renormalizable and
non-renormalizable, with arbitrary numbers of the singlet and left-handed
doublet neutrinos is systematically analyzed in the weak basis.


title:
Non-saturation of the J/psi suppression at large transverse energy in
  the comovers approach

abstract:
  We show that, contrary to recent claims, the $J/\psi$ suppression resulting
from its interaction with comovers does not saturate at large transverse energy
$E_T$. On the contrary, it shows a characteristic structure - change of
curvature near the knee of the $E_T$ distribution - which is due to the $E_T$
(or multiplicity) fluctuation, and agrees with recent experimental results.