title: Abelian family symmetries and Leptogenesis

abstract:
  We study the impact of a set of horizontal symmetries on the requirements for
producing the baryon asymmetry of the universe via leptogenesis. We find that
Abelian horizontal symmetries lead to a simple description of the parameters
describing leptogenesis in terms of the small expansion parameter that arises
from spontaneous symmetry breaking. If the family symmetry is made discrete,
then an enhancement in the amount of leptogenesis can result.


title: Harmonic Sums and Mellin Transforms

abstract:
  The finite and infinite harmonic sums form the general basis for the Mellin
transforms of all individual functions $f_i(x)$ describing inclusive quantities
such as coefficient and splitting functions which emerge in massless field
theories. We discuss the mathematical structure of these quantities.


title: Effects of threshold resummation

abstract:
  We investigate effects of threshold resummation of logarithmic corrections
$\ln N$ in Mellin space quantitatively. Threshold resummation leads to
enhancement of next-to-leading-order QCD predictions for jet production at
large jet transverse energy, which is in the trend indicated by experimental
data. We show that this enhancement is completely determined by the behavior of
threshold resummation at small $N$, the region where hierachy among different
powers of $\ln N$ is lost and current next-to-leading-logarithm resummation is
not reliable. Our analysis indicates that more accurate threshold resummation
formalism should be developed in order to obtain convincing predictions.


title:
The Contributions of Neutral Higgs Bosons to Charmless Nonleptonic B
  Decays in MSSM

abstract:
  We investigate the contributions of neutral Higgs bosons to nonleptonic
transition $b \to q \bar{s} s, q=d, s$ under the supersymmetric context. Their
effects to decay width and CP violation in corresponding exclusive decays are
explored. The anomalous dimension matrices of the operators which have to be
incorporated to include the contributions of neutral Higgs bosons are given. We
find that when tan$\beta$ is large (say, 50) and neutral Higgs bosons are not
too heavy (say, 100 GeV), contributions of neutral Higgs penguin can dominate
electroweak penguin contributions, and for some processes, they can greatly
modify both decay width and CP asymmetry.


title: The spectrum and strong couplings of heavy-light hybrids

abstract:
  The spectrum of the $0^{++}$, $0^{--}$, $1^{-+}$ and $1^{+-}$ heavy-light
hybrids have been calculated in HQET. The interpolated current of the hybrid is
chosen as $g\bar q\gamma_{\alpha}G_{\alpha\mu}^aT^ah_{\it v}(x)$, $g\bar
q\gamma_{\alpha}\gamma_{5}G_{\alpha\mu}^aT^ah_{\it v}(x)$ and $g\bar
q\sigma_{\mu\alpha}G_{\alpha\mu}^aT^ah_{\it v}(x)$. Some strong couplings and
decay widths of the heavy-light hybrids to $B(D)\pi$ are calculated by using
the QCD sum rules. The mass of $0^{++}$ hybrid with gluon in TM($1^{--}$) or
TE($1^{+-}$) mode is found similar, while their decay widths are different. A
two-point correlation function between the pion and vacuum is employed and the
leading order of $1/M_Q$ expansion is kept in our calculation.


title: $e^+e^-$ annihilation at low energies in analytic approach to QCD

abstract:
  We begin with short review of the analytic approach (AA) to QCD recently
developed and applied to the process of $e^+e^-$ annihilation into hadrons at
low energies. Besides summary of the theoretical description of smeared
experimental data for the $R$ cross-section ratio we give fresh analogous
result for the corresponding Adler function, $D(Q^2)$, and demonstrate
excellent agreement between the AA theoretical results and data in the low
$Q^2$ region.


title: Leptogenesis via preheating

abstract:
  Leptogenesis constitues a very simple scenario to achieve the baryon
asymmetry that we observe today. It requires only the presence of right handed
neutrinos (which arise very naturally in many extensions of the Standard Model)
and depends crucially on the mechanism responsible for their production. In
particular, when their mass exceeds the inflaton mass (10^13 GeV in chaotic
inflation) only non perturbative production can occur. It is shown here that
non perturbative production of fermions in an expanding Universe is a very
efficient mechanism up to masses of order of (10^17 - 10^18) GeV, and that it
can be easily applied to solve the baryon asymmetry problem.


title: Delta m_d, Delta m_s/Delta m_d and epsilon_K in Quenched QCD

abstract:
  I present quenched, lattice QCD calculations of the hadronic matrix elements
relevant for B^0_{d(s)}-\bar B^0_{d(s)} and K^0-\bar K^0 mixing and briefly
review the status of lattice predictions.


title: Constraining Leptogenesis from Laboratory Experiments

abstract:
  The presently available information on neutrino oscillations can be used to
tightly constrain the light neutrino mass matrix $m_\n$ under the assumption
that the three known neutrinos provide explanation of the solar and atmospheric
anomalies. We exploit left right symmetry and the seesaw model to establish
direct correlation between this constrained $m_\n$ and the mass matrix $M_R$
for the right handed (RH) neutrinos. Using this correlation, one could directly
relate the lepton asymmetry $\e$ generated in the decay of the lightest RH
neutrino to experimentally determined mixing angles of the light neutrinos. It
is found that the parameters required to understand neutrino anomalies also
give rise to the $\e$ in the range required to reproduce the correct baryon
asymmetry in the leptogenesis scenario. Specifically, the small angle MSW or
the the vacuum oscillation explanation of the solar anomaly can lead to correct
$\e$ for maximal value of the CP violating phases. In contrast, the large angle
MSW solution needs some suppression in CP violating phases in order to generate
the right $\e$.


title:
Polarised deep inelastic scattering accompanied by a forward jet as a
  probe of the $\ln^2(1/x)$ resummation

abstract:
  We argue that the production of forward jets in polarised deep inelastic
scattering can be a useful tool for probing the double $ln^2(1/x)$ resummation
effects which control the polarised deep inelastic scattering for small values
of the Bjorken parameter $x$. We solve the corresponding integral equations
generating the double $ln^2(1/x)$ resummation and calculate the differential
structure function describing the forward jet production in the small $x$
regime which can possibly be probed by the polarised HERA measurements. We show
that these structure functions should exhibit the characteristic increase with
decreasing $x/x_J$, where $x_J$ denotes the longitudinal momentum fraction of
the parent proton carried by a jet, and we quantify this increase.


title:
The effects of nonextensive statistics on fluctuations investigated in
  event-by-event analysis of data

abstract:
  We investigate the effect of nonextensive statistics as applied to the
chemical fluctuations in high-energy nuclear collisions discussed recently
using the event-by-event analysis of data. It turns out that very minuite
nonextensitivity changes drastically the expected experimental output for the
fluctuation measure. This results is in agreement with similar studies of
nonextensity performed recently for the transverse momentum fluctuations in the
same reactions.


title:
Preheating with non-minimally coupled scalar fields in higher-curvature
  inflation models

abstract:
  In higher-curvature inflation models ($R+\alpha_n R^n$), we study a
parametric preheating of a scalar field $\chi$ coupled non-minimally to a
spacetime curvature $R$ ($\xi R \chi^2$). In the case of $R^2$-inflation model,
efficient preheating becomes possible for rather small values of $\xi$, i.e.
$|\xi|< several. Although the maximal fluctuation $\sqrt{< \chi^2 >}_{max}
\approx 2 \times10^{17}$ GeV for $\xi \approx -4$ is almost the same as the
chaotic inflation model with a non-minimally coupled $\chi$ field, the growth
rate of the fluctuation becomes much larger and efficient preheating is
realized. We also investigate preheating for $R^4$ model and find that the
maximal fluctuation is $\sqrt{< \chi^2 >}_{max} \approx 8 \times 10^{16}$ GeV
for $\xi \approx -35$.


title:
Rare Radiative B -> \tau^+ \tau^- \gamma decay in the two Higgs doublet
  Model

abstract:
  The radiative B ->\tau^+ \tau^- \gamma decay is investigated in the framework
of the two Higgs doublet model . The dependence of the differential branching
ratio on the photon energy and the branching ratio on the two Higgs doublet
model parameters, m_{H^\pm} and \tan \beta, are studied. It is shown that there
is an enhancement in the predictions of the two Higgs doublet model compared to
the Standard model case. We also observe that contributions of neutral Higgs
bosons to the decay are sizable when \tan\beta is large.


title: Azimuthal Asymmetries in Hadronic Final States at HERA

abstract:
  The distribution of hadrons produced in deeply inelastic electron-proton
collisions depends on the azimuthal angle between lepton scattering plane and
hadron production plane in the photon-proton centre-of-mass frame. In addition
to the well known up-down asymmetry induced by the azimuthal dependence of the
Born level subprocess, there is also a non-vanishing left-right asymmetry,
provided the incoming electron is polarized. This asymmetry is
time-reversal-odd and induced by absorptive corrections to the Born level
process. We investigate the numerical magnitude of azimuthal asymmetries in
semi-inclusive hadron production at HERA with particular emphasis on a possible
determination of the time-reversal-odd asymmetry.


title: Measuring $|V_{ub}|$ with B$\to D_s^+ X_u$ transitions

abstract:
  We propose the determination of the CKM matrix element $|V_{ub}|$ by the
measurement of the spectrum of $B \to D_s^+ X_u$, dominated by the spectator
quark model mechanism $\bar{b} \to D_s^{(*)+} \bar{u}$. The interest of
considering $B \to D_s^+X_u$ versus the semileptonic decay is that more than 50
% of the spectrum for $B \to D_s^+ X_u$ occurs above the kinematical limit for
$B \to D_s^+ X_c$, while most of the spectrum $B \to l \nu X_u$ occurs below
the $B \to l \nu X_c$ one. Furthermore, the measure of the hadronic mass $M_X$
is easier in the presence of an identified $D_s$ than when a $\nu$ has been
produced. As a consistency check, we point out that the rate $\bar{b} \to
D_s^{(*)+} \bar{c}$ (including QCD corrections that we present elsewhere) is
consistent with the measured $BR (B \to D_s^{\pm} X)$. Although the hadronic
complications may be more severe in the mode that we propose than in the
semileptonic inclusive decay, the end of the spectrum in $B \to l \nu X_u$ is
not well understood on theoretical grounds. We argue that, in our case, the
excited $D_s^{**}$, decaying into $D K$, do not contribute and, if there is
tagging of the $B$ meson, the other mechanisms to produce a $D_s$ of the right
sign are presumably small, of $O(10^{-2})$ relative to the spectator amplitude,
or can be controlled by kinematical cuts. In the absence of tagging, other
hadronic backgrounds deserve careful study. We present a feasability study with
the BaBar detector.


title: Inclusive decay of B mesons into $D_s$ or $D^*_s$

abstract:
  We compute the inclusive decay rates $b \to D_s^-(D^{*-}_s) c$ including
lowest order QCD corrections on the quark legs, and compare with existing data.
Unlike the short distance QCD corrections, that are of higher order, these
corrections are of order $\alpha_s$. In the on-shell renormalization scheme and
for $\alpha_s(m_b) \cong 0.2$ we find a correction of -10% to the inclusive
rate computed using factorization. This gives a total rate $BR(b \to
D_s^-(D^{*-}_s)c) \cong 8%$ consistent within $1\sigma$ with the measured value
$BR(B \to D_s^{\pm}X) = (10.0 \pm 2.5)%$. The general formulae given here
include the case of vanishing mass for the final quark $b \to
D_s^-(D_s^{*-})u$. The radiative correction to this rate is -17%. We show in
another place that this process can be useful for the measurement of the CKM
matrix element $V_{ub}$. We also give the renormalized vertex at the
interesting values $q^2 = 0$ and $q^2 = q_{max}^2$, and compare with existing
literature.


title: New Higgs Couplings at Tevatron

abstract:
  We investigate the potentiality of CERN LEP and Fermilab Tevatron colliders
to establish bounds on new couplings involving the bosonic sector of the
standard model. A combined exclusion plot for the coefficients of different
dimension-6 anomalous operators is presented. We also discuss the sensitivity
that can be achieved at the upgraded Tevatron.


title: Sparticle spectrum in M-theory with five-brane dominance

abstract:
  The phenomenological implications of the M-theory limit in which
supersymmetry is broken by the F-terms of five-brane moduli is investigated. In
particular we calculate the supersymmetric spectrum subject to constraints of
correct electroweak symmetry breaking. We find interesting differences
especially in the squark sector compared with $M$-theory scenarios with
standard embedding and weakly-coupled Calabi-Yau compactifications in the large
$T$-limit.


title:
A gauge-mediated supersymmetry breaking model with an extra singlet
  Higgs field

abstract:
  We study in some detail the next-to-minimal supersymmetric standard model
with gauge mediation of supersymmetry breaking. We find that it is feasible to
spontaneously generate values of the Higgs mass parameters $\mu$ and $B_\mu$
consistent with radiative electroweak symmetry breaking. The model has a
phenomenologically viable particle spectrum. Messenger sneutrinos with mass in
the range 6 to 25 TeV can serve as cold dark matter. It is also possible to
evade the cosmological domain wall problem in this scenario.


title: Neutrino Physics

abstract:
  These lectures describe some aspects of the physics of massive neutrinos.
After a brief introduction of neutrinos in the Standard Model,
  I discuss possible patterns for their masses.
  In particular, I show how the presence of a large Majorana mass term for the
right-handed neutrinos can engender tiny neutrino masses for the observed
neutrinos. If neutrinos have mass, different flavors of neutrinos can oscillate
into one another. To analyze this phenomena,
  I develop the relevant formalism for neutrino oscillations, both in vacuum
and in matter. After reviewing the existing (negative) evidence for neutrino
masses coming from direct searches, I discuss evidence for, and hints of,
neutrino oscillations in the atmosphere, the sun, and at accelerators. Some of
the theoretical implications of these results are emphasized. I close these
lectures by briefly outlining future experiments which will shed further light
on atmospheric, accelerator and solar neutrino oscillations. A pedagogical
discussion of Dirac and Majorana masses is contained in an appendix.


title:
Electric Screening Mass of the Gluon with Condensate at Finite
  Temperature

abstract:
  The electric screening mass of the gluon at finite temperature is estimated
by considering the gluon condensate above the critical temperature. We find
that the thermal gluons acquire an electric mass of order T due to the gluon
condensate.


title: Peripheral Meson Model of Deep Inelastic Rapidity Gap Events

abstract:
  We show that a peripheral meson model can explain the large deep inelastic
electron-proton scattering rapidity gap events observed at HERA.


title:
Superconductivity from perturbative one-gluon exchange in high density
  quark matter

abstract:
  We study color superconductivity in QCD at asymptotically large chemical
potential. In this limit, pairing is dominated by perturbative one-gluon
exchange. We derive the Eliashberg equation for the pairing gap and solve this
equation numerically. Taking into account both magnetic and electric gluon
exchanges, we find $\Delta\sim g^{-5}\exp(-c/g)$ with $c=3\pi^2/\sqrt{2}$,
verifying a recent result by Son. For chemical potentials that are of physical
interest, $\mu< 1$ GeV, the calculation ceases to be reliable quantitatively,
but our results suggest that the gap can be as large as 100 MeV.


title: Cosmology of One Extra Dimension with Localized Gravity

abstract:
  We examine the cosmology of the two recently proposed scenarios for a five
dimensional universe with localized gravity. We find that the scenario with a
non-compact fifth dimension is potentially viable, while the scenario which
might solve the hierarchy problem predicts a contracting universe, leading to a
variety of cosmological problems.


title: Gauge coupling unification with large extra dimensions

abstract:
  We make a detailed study of the unification of gauge couplings in the MSSM
with large extra dimensions. We find some scenarios where unification can be
achieved (with the strong coupling constant at the Z mass within one standard
deviation of the experimental value) with both the compactification scale and
the SUSY breaking scale in the few TeV range. No enlargement of the gauge group
or particle content is needed. One particularly interesting scenario is when
the SUSY breaking scale is larger than the compactification scale, but both are
small enough to be probed at the CERN LHC. Unification in two scales scenarios
is also investigated and found to give results within the LHC.


title: Omega_{ccc} production via fragmentation at LHC

abstract:
  In the framework of the leading order of perturbative QCD and the
nonrelativistic quark-diquark model of baryons we have obtained fragmentation
function for c-quark to split into Omega_{ccc} baryon. It is shown that at LHC
one can expect 3.5 10^3 events with Omega_{ccc} at p_t>5 GeV/c and -1<y<1 per
year.


title: Search for CP Violation with a Neutrino Factory

abstract:
  We have discussed the search of the genuine CP violation in a neutrino
factory, in which well known neutrino beams are provided by a high intensity
muon storage ring. Both $\Delta P(\n_\a \Ar \n_\b)$ and CP odd asymmetry
$A_{CP}$ in neutrino oscillations are investigated by taking account of the
atmospheric neutrino data and the solar neutrino data. If the large mixing
angle MSW solution is taken, the magnitude of $\Delta P(\n_e \Ar \n_\m)$ could
be 1%. If $s_{13}$ is lower than 0.05 with the maximal CP violating phase, the
matter effect is negligible in $\Delta P(\n_e \Ar \n_\m)$ and $A_{CP}$. We have
proposed how to extract the genuine CP violation effect in the three family
scheme from the neutrino oscillation data $\Delta P(\n_e \Ar \n_\m)$, $\Delta
P(\n_\m \Ar \n_e)$ and $\Delta P(\n_e \Ar \n_\tau)$.


title:
Supersymmetric radiative corrections to top quark and Higgs boson
  physics

abstract:
  In this Thesis we have investigated some effects appearing in top quark
observables in the framework of the Minimal Supersymmetric Standard Model
(MSSM). We have computed the radiative corrections to some top quark
observables, using the on-shell renormalization scheme, and with a physically
motivated definition of the tan(beta) parameter. Introductory chapters deal
with the MSSM, its renormalization, and the on-shell prescription. In the next
chapters we have computed the SUSY-EW corrections (and some SUSY-QCD
corrections) to: the non-standard top quark decay partial width \Gamma(t->H+
b); the FCNC top quark decay width \Gamma(t-> c h) (h=h^0,H^0,A^0); and the
non-standard top quark production through sbottom decays \Gamma(sbottom -> t
\chi^-). We have investigated the consequences of the corrections to
\Gamma(t->H^+ b) in the interpretation of the present Tevatron data. Our
general conclusion is that the supersymmetric strong and electroweak radiative
corrections can be very important in the top/bottom-Higgs super-sector of the
MSSM. Therefore, it is necessary to account for these corrections in the
theoretical computation of the high energy physics observables, otherwise
highly significant information on the potentially underlying SUSY dynamics
could be missed. This is true, not only for the future experiments at the LHC
and the LC, but also for the present Run I data (and the Run II data around the
corner) at the Fermilab Tevatron collider.


title: Diffractive Interactions: Theory Summary

abstract:
  I review various theory issues in diffraction that have been presented and
discussed in the working group on diffractive interactions, and a few points
concerning the comparison of theory with data.


title: Nonlinear effects in Schwinger-Dyson Equation

abstract:
  We study nonlinear effects in the QED ladder Schwinger-Dyson(SD) equation.
Without further approximations, we show that all nonlinear effects in the
ladder SD equation can be included in the effective couplings and how a linear
approximation works well. The analyses is generalized in the case of the
improved ladder calculation with the Higashijima-Miransky approximation.


title:
Measuring the finite width and unitarity corrections to the phi-omega
  mixing amplitude

abstract:
  It is shown that the phase of phi-omega interference in the reaction e^+e^-
-->pi^+ pi^- pi^0 at energies close to the phi(1020) peak can be calculated in
a way that is practically independent of the model of phi-omega mixing. The
magnitude of the presently measured interference phase, still of poor accuracy,
is in agreement with the predictions based on extending the omega(782)
resonance tail from the peak position to the phi mass upon assuming the omega
-->rho pi -->3pi model. The calculated omega width at the phi mass is about 200
MeV.


title: Yukawa Unification on the Bilinear R-Parity model

abstract:
  We discuss gauge and Yukawa unification in the context of a supersymmetric
model with bilinear R-parity violation. We show that this model allows $b-\tau$
Yukawa unification for any value of $\tan\beta$ while satisfying perturbativity
of the couplings. We also find the $t-b-\tau$ Yukawa unification easier to
achieve than in the MSSM, occurring in a wider high $\tan\beta$ region. Finaly,
we also discuss the compatibility between the predicted and the measured values
for $\alpha_s(M_Z)$


title: Weak magnetism in chiral quark models

abstract:
  We discuss symmetry breaking in the weak magnetism form factors for the
semileptonic octet baryon decays. In the chiral quark model, the symmetry
breaking can be accounted for in the masses and the quark spin polarizations
can take on more general values due to Goldstone boson depolarization. Here we
clarify some features of the chiral quark model prediction for the weak
magnetism and compare to the corresponding result of the chiral quark soliton
model.


title: Cosmological Expansion in the Presence of an Extra Dimension

abstract:
  It has recently been pointed out that global solutions of Einstein's
equations for a 3-brane universe embedded in 4 spatial dimensions give rise to
a Friedmann equation of the form H ~ rho on the brane, instead of the usual H ~
(rho)^{1/2}, which is inconsistent with cosmological observations. We remedy
this problem by adding cosmological constants to the brane and the bulk, as in
the recent scenario of Randall and Sundrum. Our observation allows for normal
expansion during nucleosynthesis, but faster than normal expansion in the very
early universe, which could be helpful for electroweak baryogenesis, for
example.


title: Testing the Meson Cloud Model in Inclusive Meson Production

abstract:
  We have applied the Meson Cloud Model to calculate inclusive momentum spectra
of pions and kaons produced in high energy proton-proton and proton-nucleus
collisions. For the first time these data are used to constrain the cloud
cut-off parameters. We show that it is possible to obtain a reasonable
description of data, especially the large $x_F$ ($x_F \geq 0.2$) part of the
spectrum and at the same time describe (partially) the E866 data on $\bar d -
\bar u$ and $\bar d / \bar u$. We also discuss the relative strength of the
$\pi N$ and $\pi \Delta$ vertices. We find out that the corresponding cut-off
parameters should be both soft and should not differ by more than 200 MeV from
each other. An additional source (other than the meson cloud) of sea antiquark
asymmetry, seems to be necessary to completely explain the data. A first
extension of the MCM to proton nucleus collisions is discussed.


title:
Signal of neutrinoless double beta decay, neutrino spectrum and
  oscillation scenarios

abstract:
  The lower and upper bounds on the neutrinoless double beta (0nu-2beta) decay
rate are obtained, as functions of the parameters of neutrino oscillations and
of the lightest neutrino mass. The constraints on these parameters from the
search for the 0nu-2beta transition, as well as from the interpretation of
solar and atmospheric neutrino data in terms of oscillations, can be
conveniently represented in one unitarity triangle. This representation helps
to clarify the cases when the 0nu-2beta rate is small; the crucial dependence
on the scenarios assumed for solar neutrino oscillations and on the neutrino
spectrum is emphasized. We consider hierarchical and non-hierarchical neutrino
spectra, and discuss their interest in view of future searches of the 0nu-2beta
decay.


title: Direct and Indirect Searches for Low-Mass Magnetic Monopoles

abstract:
  Recently, there has been renewed interest in the search for low-mass magnetic
monopoles. At the University of Oklahoma we are performing an experiment
(Fermilab E882) using material from the old D0 and CDF detectors to set limits
on the existence of Dirac monopoles of masses of the order of 500 GeV. To set
such limits, estimates must be made of the production rate of such monopoles at
the Tevatron collider, and of the binding strength of any such produced
monopoles to matter. Here we sketch the still primitive theory of such
interactions, and indicate why we believe a credible limit may still be
obtained. On the other hand, there have been proposals that the classic
Euler-Heisenberg Lagrangian together with duality could be employed to set
limits on magnetic monopoles having masses less than 1 TeV, based on virtual,
rather than real processes. The D0 collaboration at Fermilab has used such a
proposal to set mass limits based on the nonobservation of pairs of photons
each with high transverse momentum. We critique the underlying theory, by
showing that the cross section violates unitarity at the quoted limits and is
unstable with respect to radiative corrections. We therefore believe that no
significant limit can be obtained from the current experiments, based on
virtual monopole processes.


title: Wino Cold Dark Matter from Anomaly-Mediated SUSY Breaking

abstract:
  The cosmological moduli problem is discussed in the framework of sequestered
sector/anomaly-mediated supersymmetry (SUSY) breaking. In this scheme, the
gravitino mass (corresponding to the moduli masses) is naturally 10 - 100 TeV,
and hence the lifetime of the moduli fields can be shorter than $\sim 1 sec$.
As a result, the cosmological moduli fields should decay before big-bang
nucleosynthesis starts. Furthermore, in the anomaly-mediated scenario, the
lightest superparticle (LSP) is the Wino-like neutralino. Although the large
annihilation cross section means the thermal relic density of the Wino LSP is
too small to be the dominant component of cold dark matter (CDM), moduli decays
can produce Winos in sufficient abundance to constitute CDM. If Winos are
indeed the dark matter, it will be highly advantageous from the point of view
of detection. If the halo density is dominated by the Wino-like LSP, the
detection rate of Wino CDM in Ge detectors can be as large as $0.1 - 0.01$
event/kg/day, which is within the reach of the future CDM detection with Ge
detector. Furthermore, there is a significant positron signal from pair
annihilation of Winos in our galaxy which should give a spectacular signal at
AMS.


title:
Short Distance Analysis of $\bar B -> D^{(*)0} e+e-$ and $\bar B ->
  J/psi e+e-$

abstract:
  Over a large fraction of phase space a combination of an operator product and
heavy quark expansions effectively turn the decay $\bar B -> D^{(*)0} e+e-$
into a ``short distance'' process, i.e., one in which the weak and
electromagnetic interactions occur through single local operators. These
processes have an underlying W-exchange quark diagram topology and are
therefore Cabibbo allowed but suppressed by combinatoric factors and short
distance QCD corrections. Our technique allows a clearer exploration of these
effects. For the decay $\bar B_{d,s} -> J/psi(\eta_c) e+e-$ one must use a
non-relativistic (NRQCD) expansion, in addition to an operator product
expansion and a heavy quark effective theory expansion. We estimate the decay
rates for $\bar B_{d,s} -> J/psi e+e-$, $\bar B_{d,s} -> eta_c e+e-$, $\bar
B_{d,s} -> D^{*0} e+e-$ and $\bar B_{d,s} -> D^{0} e+e-$.


title:
Weak Matrix Elements and |V_cb| in New Formulation of Heavy Quark
  Effective Field Theory

abstract:
  The heavy quark effective field theory (HQEFT) containing both effective
`quark fields' and `antiquark fields' is investigated in detail. By integrating
out (but not neglecting) the effective antiquark fields, we present a new
formulation of effective theory which differs from the usual heavy quark
effective theory (HQET) and exhibits valuable features because of the inclusion
of the contributions from the antiquark fields. Matrix elements of vector and
axial vector heavy quark currents between pseudoscalar and vector mesons
containing a heavy quark (b or c) are then evaluated systematically up to the
order of $1/m^2_Q$ and parameterized by a set of universal form factors. With a
consistent normalization condition between the effective heavy hadron states,
the form factors at zero recoil are related to the ground state meson masses,
which enables us to estimate the values of form factors at zero recoil. In
particular, the Luke's theorem comes out automatically in the new formulation
of HQEFT without the need of imposing the equation of motion $iv\cdot D
Q^{+}_{v} =0$. Consequently, the differential decay rates of both $B\to
D^{\ast}l\nu$ and $B\to D l\nu$ do not receive $1/m_{Q}$ order corrections at
zero recoil, which is not the case in the usual HQET. Thus we quote that the
Cabibbo-Kobayashi-Maskawa matrix element $| V_{cb}|$ can nicely be extracted
from either of these two exclusive semileptonic decays at the order of
$1/m^2_Q$. Our estimates for $|V_{cb}|$ are presented.


title: Solar Neutrinos and Leptonic CP Violation

abstract:
  We examine the possibility of detecting effects of leptonic CP violation by
precise measurement of the solar neutrinos within the framework of standard
electroweak theory minimally extended to include neutrino masses and mixing. We
prove a ``no-go theorem'' which states that effects of CP violating phase
disappear in the nu_e survival probability to the leading order in electroweak
interaction. The effects due to the next-to-leading order correction is
estimated to be extremely small, effectively closing the door to the
possibility we intended to pursue.


title:
Photon-Photon and Photon-Hadron Physics at Relativistic Heavy Ion
  Colliders

abstract:
  Due to the coherence of all the protons in a nucleus, there are very strong
electromagnetic fields of short duration in relativistic heavy ion collisions.
They give rise to quasireal photon-photon and photon-nucleus collisions with a
large flux. RHIC will begin its experimental program this year and such types
of collisions will be studied experimentally at the STAR detector. RHIC will
have the highest flux of (quasireal) photons up to now in the GeV region. At
the LHC the invariant mass range available in gamma-gamma-interactions will be
of the order of 100 GeV, i.e., in the range currently available at LEP2, but
with a higher gamma-gamma-luminosity. Therefore one has there also the
potential to study new physics. (Quasireal) photon-hadron (i.e.,
photon-nucleus) interactions can be studied as well, similar to HERA, at higher
invariant masses. Vector mesons can be produced coherently through
photon-Pomeron and photon-meson interactions in exclusive reactions such as A+A
-> A+A+V, where A is the heavy ion and V=rho,omega,phi or J/Psi.


title: Physics for a Polarized Electron-Nucleon/Nucleus-Collider

abstract:
  A number of physics arguments for a high-luminosity high energy polarized
Electron- Nucleon/Nucleus-Collider (i.e. with a luminosity of at least 10^{33}
cm^{-2} sec^{-1} and an invariant energy squarred of at least s >= 100 GeV^2)
are presented. The main purpose of this machine would be generally speaking the
investigation of QCD beyond the twist-2 level respectively of nuclear physics
beyond the level of 'effective' models. Specific topics are: twist-2 and
twist-3 spin-asymmetries as probes of both the internal hadron structure and
the hadronization process, Off-Forward-Parton-Distributions as a new dimension
of QCD-physics, nuclear effects for the nucleon structure and nuclear effects
for QCD-dynamics in nuclei. The last two topics are also of direct relevance
for high-energy heavy-ion-collisons. We conclude that the need for such a
collider is clear, if nuclear physics is to continue its development towards a
comprehensive understanding of QCD phenomena.


title: Electric dipole moments, present and future

abstract:
  Upper limits on the electric dipole moments (EDM) of elementary particles and
atoms are presented, and their physical implications are discussed. The bounds
following from the neutron and atomic experiments are comparable. In
particular, they strongly constrain P odd, T even interactions. The nuclear
EDMs can be studied at ion storage rings, with the expected sensitivity much
better than $10^{-24} e$ cm. It would be a serious progress in the studies of
the CP violation.


title: Adler function from R^{e^+e^-} measurements: experiments vs QCD theory

abstract:
  An experimental motivated QCD analysis of the behaviour of the Adler
D-function in the Euclidian region is described. It is stressed that by taking
account of $b$-quark mass-dependent $\alpha_s^2$-effects one obtains better
agreement between theoretical predictions and experimentally motivated
behaviour of the D-function at large Euclidian momentum transfer. A more
detailed analysis of QCD predictions, including information on quark and gluon
condensates, requires more precise data on $e^+e^-\to{hadrons}$, particularly
in the region $E<M_{J/\Psi}$ and $M_{J/\Psi}<E<3.6 GeV$. use of experimental
determination of the D-function to test the generalized Crewther relation is
outlined.


title: Supersymmetric hadronic bound state detection at $e^+e^-$ colliders

abstract:
  We review the possibility of formation for a bound state made out of a stop
quark and its antiparticle. The detection of a signal from its decay has been
investigated for the case of a $e^+e^-$ collider.


title: Transverse Spectra of Radiation Processes in Medium

abstract:
  We develop a formalism for evaluation of the transverse momentum dependence
of cross sections of the radiation processes in medium. The analysis is based
on the light-cone path integral approach to the induced radiation. The results
are applicable in both QED and QCD.


title: Closing the Low-mass Axigluon Window

abstract:
  In this report, I will present the current status of the low-mass axigluon.
The axigluon is a massive, color octet, axial vector boson, predicted in, e.g.,
chiral color models and some technicolor models, with a mass of order the
electroweak scale. Axigluons with a mass larger than about 125 GeV to nearly 1
TeV can be eliminated by di-jet production at hadron colliders like the
TEVATRON, but a low-mass window exists that the di-jet search can not probe.
Upsilon decays can rule out axigluons with a mass up to 25 GeV, and low energy
e^+ e^- (PEP and PETRA) can rule out axigluons with a mass up to 50 GeV using a
measurement of R. Top production at the TEVATRON disfavors a light axigluon. A
measurement of R at LEP strongly disfavors a light axigluon, and rules out an
axigluon with mass < 365 GeV.


title:
Particle Production and Effective Thermalization in Inhomogeneous Mean
  Field Theory

abstract:
  As a toy model for dynamics in nonequilibrium quantum field theory we
consider the abelian Higgs model in 1+1 dimensions with fermions. In the
approximate dynamical equations, inhomogeneous classical (mean) Bose fields are
coupled to quantized fermion fields, which are treated with a mode function
expansion. The effective equations of motion imply e.g. Coulomb scattering, due
to the inhomogeneous gauge field. The equations are solved numerically. We
define time dependent fermion particle numbers with the help of the single-time
Wigner function and study particle production starting from inhomogeneous
initial conditions. The particle numbers are compared with the Fermi-Dirac
distribution parametrized by a time dependent temperature and chemical
potential. We find that the fermions approximately thermalize locally in time.


title:
On the Interpretation of the Atmospheric Neutrino Data in Terms of
  Flavor Changing Neutrino Interactions

abstract:
  Flavour changing (FC) neutrino-matter interactions have been proposed as a
solution to the atmospheric neutrino anomaly. Here we perform the analysis of
the full set of the recent 52 kTy Super-Kamiokande atmospheric neutrino data,
including the zenith angle distribution of the contained events as well as the
higher energy upward-going stopping and through-going muon events. Our results
show that the FC mechanism can describe the full data sample with a
chi^2_{min}=44/(33 d.o.f) which is acceptable at the 90% confidence level. The
combined analysis confines the amount of FC to be either close to maximal or to
the level of about (10-50)%.


title: Latest Highlights from the H1 Collaboration

abstract:
  Recent data obtained in ep collisions at HERA by the H1 collaboration are
presented: searches for new phenomena beyond the Standard Model, measurement of
the inclusive neutral and charged current cross sections and of the proton
structure function, determination of the gluon density in the proton and photon
from jet productions, measurement and interpretation of event shapes in the
current region of the Breit frame, test of the parton evolution at low x and of
the diffractive production mechanism.


title: Renormalisation Scale Dependencies in Dijet Production at HERA

abstract:
  Different choices of the renormalisation scale (muren) can be used to
describe hard scattering processes with two jets at large transverse momentum
in deep-inelastic scattering at HERA by fixed order perturbative QCD
calculations.
  For leading (LO) and next-to-leading order (NLO) calculations the simplest
choices, Q2, the virtuality of the incoming photon, and the mean squared
transverse momenta of the two jets ET2, are studied in different kinematic
regimes.
  It is found that only if both Q2 and ET2 are large, the NLO calculation is
stable with respect to numerical variations of muren while the LO calculation
strongly depends on it. If only one of the two scales, either Q2 or ET2, is
large, the NLO is more stable than the LO calculation, but exhibits
nevertheless a strong residual scale dependence.
  When both scales are relatively small, large scale dependencies are found in
both cases. Moreover, large differences between the LO and NLO calculation are
found.
  Generally, the use of ET2 as renormalisation scale is favoured over Q2, since
scale dependencies are less pronounced and NLO corrections are smaller.


title:
Cosmological Challenges in Theories with Extra Dimensions and Remarks on
  the Horizon Problem

abstract:
  We consider the cosmology that results if our observable universe is a
3-brane in a higher dimensional universe. In particular, we focus on the case
where our 3-brane is located at the $Z_2$ symmetry fixed plane of a $Z_2$
symmetric five-dimensional spacetime, as in the Ho\v{r}ava-Witten model
compactified on a Calabi-Yau manifold. As our first result, we find that there
can be substantial modifications to the standard Friedmann-Robertson-Walker
(FRW) cosmology; as a consequence, a large class of such models is
observationally inconsistent. In particular, any relationship between the
Hubble constant and the energy density on our brane is possible, including (but
not only) FRW. Generically, due to the existence of the bulk and the boundary
conditions on the orbifold fixed plane, the relationship is not FRW, and hence
cosmological constraints coming from big bang nucleosynthesis, structure
formation, and the age of the universe difficult to satisfy. We do wish to
point out, however, that some specific choices for the bulk stress-energy
tensor components do reproduce normal FRW cosmology on our brane, and we have
constructed an explicit example. As our second result, for a broad class of
models, we find a somewhat surprising fact: the stabilization of the radius of
the extra dimension and hence the four dimensional Planck mass requires
unrealistic fine-tuning of the equation of state on our 3-brane. In the last
third of the paper, we make remarks about causality and the horizon problem
that apply to {\it any} theory in which the volume of the extra dimension
determines the four-dimensional gravitational coupling. We point out that some
of the assumptions that lead to the usual inflationary requirements are
modified.


title: Chiral Dynamics

abstract:
  After a short summary of my talk, I discuss $K_{l3}$ decays and elastic
$\pi\pi$ scattering in the framework of chiral perturbation theory.


title: Hadroproduction of particle with open charm

abstract:
  In the framework of Quark-Gluon-String Model (QGSM) we calculate the
inclusive spectra of meson and baryons with open charm in hadron-hadron
collisions, obtained by SELEX and BEATRICE collaborations, taking into account
the decays of corresponding S-wave resonances.


title: Sudakov logarithms in electroweak processes

abstract:
  The dominant electroweak double logarithmic corrections to the process
$e^+e^-\to f\bar f$ at high energy are found in all orders of perturbation
theory. In contrast to results in simple Yang-Mills theories these corrections
do not exponentiate.


title: Towards the Theory of Diffractive DIS

abstract:
  The large rapidity gap events, observed at HERA, have changed considerably
our physical picture of deep inelastic scattering during the past years. We
review the present theoretical understanding of diffractive DIS with emphasis
on the close relation to inclusive DIS. This includes success and limitations
of the leading twist description, the connection between diffractive and
inclusive parton distributions in the semiclassical approach, the colour
structure of the proton and comparison with data. The progress report concludes
with a list of open questions.


title:
Deep-inelastic Electron-Photon Scattering at High Q^2 : Neutral and
  Charged Current Reactions

abstract:
  We present the results of a calculation of deep inelastic electron-photon
scattering at a linear collider for very high virtuality of the intermediate
gauge boson up to NLO in perturbative QCD. The real photon is produced
unpolarized via the Compton back scattering of laser light of the incoming
beam. For $Q^2$ values close to the masses squared of the Z and W gauge bosons,
the deep inelastic electron-photon scattering process receives important
contributions not only from virtual photon exchange but also from the exchange
of a Z-boson and a W-boson. We find that the total cross section for center of
mass energies above $500 \rm{GeV}$ is at least of ${\cal O}(pb)$ and has an
important charged current contribution.


title:
Local equilibrium in heavy ion collisions. Microscopic model versus
  statistical model analysis

abstract:
  The assumption of local equilibrium in relativistic heavy ion collisions at
energies from 10.7 AGeV (AGS) up to 160 AGeV (SPS) is checked in the
microscopic transport model. Dynamical calculations performed for a central
cell in the reaction are compared to the predictions of the thermal statistical
model. We find that kinetic, thermal and chemical equilibration of the
expanding hadronic matter are nearly approached late in central collisions at
AGS energy for $t \geq 10$ fm/$c$ in a central cell. At these times the
equation of state may be approximated by a simple dependence $P \cong
(0.12-0.15) \epsilon$. Increasing deviations of the yields and the energy
spectra of hadrons from statistical model values are observed for increasing
energy, 40 AGeV and 160 AGeV. These violations of local equilibrium indicate
that a fully equilibrated state is not reached, not even in the central cell of
heavy ion collisions at energies above 10 AGeV. The origin of these findings is
traced to the multiparticle decays of strings and many-body decays of
resonances.


title: Brane fluctuations and suppression of Kaluza-Klein mode couplings

abstract:
  In higher dimensional models where the gauge and gravity fields live in the
bulk and the matter fields only in a brane, we point out the importance of the
brane (transverse) coordinate modes, which are the Nambu-Goldstone bosons
appearing as a result of spontaneous breaking of the translation symmetry. The
brane recoil effect suppresses the couplings of higher Kaluza-Klein modes to
the matter, and gives a natural resolution to the divergence problem caused by
the exchange of infinitely many Kaluza-Klein modes.


title: Studying the Perturbative Reggeon

abstract:
  We consider the flavour non-singlet Reggeon within the context of
perturbative QCD. This consists of ladders built out of ``reggeized'' quarks.
We propose a method for the numerical solution of the integro-differential
equation for the amplitude describing the exchange of such a Reggeon. The
solution is known to have a sharp rise at low values of Bjorken-x when applied
to non-singlet quantities in deep-inelastic scattering. We show that when the
running of the coupling is taken into account this sharp rise is further
enhanced, although the Q^2 dependence is suppressed by the introduction of the
running coupling. We also investigate the effects of simulating
non-perturbative physics by introducing a constituent mass for the soft quarks
and an effective mass for the soft gluons exchanged in the t-channel.


title: Qualitons At High Density

abstract:
  In the color-flavor-locked (CFL) phase of the QCD superconductor we show that
baryons behave as qualitons (called "superqualitons") with quantum numbers
$B=(1 {\rm mod} 2)/3$, S=1/2 and Y=B. An intriguing possibility implied by this
identification is that light baryonic modes in the form of superqualitons could
be excited below the (color) superconducting gap in the CFL phase, a novel
phenomenon foreign to normal superconductors.


title: Partonic structure of the virtual photon

abstract:
  Interactions of virtual photons are analyzed in terms of their parton
distribution functions. It is shown that the concept of parton distribution
functions is phenomenologically very useful even for highly virtual photonds
involved in hard collisions. The role of the longitudinal photons for proper
interpretation of the data on jet cross--sections in the region of moderate
photon virtualities accessible at HERA is explored.


title: Uncertainty of the Solar Neutrino Energy Spectrum

abstract:
  The solar neutrino spectrum measured by the Super-Kamiokande shows an excess
in high energy bins, which may be explained by vacuum oscillation solution or
$hep$ neutrino effect. Here we reconsider an uncertainty of the data caused by
the tail of the energy resolution function. Events observed at energy higher
than 13.5 MeV are induced by the tail of the resolution. At Super-Kamiokande
precision level this uncertainty is no more than few percent within a Gaussian
tail. But a power-law decay tail at 3 $\sigma$ results considerable excesses in
these bins, which may be another possible explanation of the anomaly in
708d(825d) data.


title: Out-of-equilibrium dynamics of \phi^4 QFT in finite volume

abstract:
  The $\lambda \phi^4$ model in a finite volume is studied in the infinite $N$
limit and within a non-gaussian Hartree-Fock approximation both at equilibrium
and out of equilibrium, with particular attention to certain fundamental
features of the broken symmetry phase. The numerical solution of the dynamical
evolution equations show that the zero-mode quantum fluctuations cannot grow
macroscopically large starting from microscopic initial conditions. Thus we
conclude that there is no evidence for a dynamical Bose-Einstein condensation.
On the other hand, out of equilibrium the long-wavelength fluctuations do scale
with the linear size of the system, signalling dynamical infrared properties
quite different from the equilibrium ones characteristic of the same
approximation schemes. This result suggests the cause, and the possible remedy,
of some unlikely features of the application to out--of--equilibrium dynamics
of the standard HF factorization scheme, which coincides with the gaussian
restriction of our Hartree--Fock approximation.


title: Enhanced Global Symmetries and The Chiral Phase Transition

abstract:
  We examine the possibility that the physical spectrum of a vector-like gauge
field theory exhibits an enhanced global symmetry near a chiral phase
transition. A transition from the Goldstone phase to the symmetric phase is
expected as the number of fermions N_f is increased to some critical value.
Various investigations have suggested that a parity-doubled spectrum develops
as the critical value is approached. Using an effective Lagrangian as a guide,
we note that parity doubling is associated with the appearance of an enhanced
global symmetry in the spectrum of the theory. The enhanced symmetry would
develop as the spectrum splits into two sectors, with the first exhibiting the
usual pattern of a spontaneously broken chiral symmetry, and the second
exhibiting an additional, unbroken symmetry and parity doubling. The first
sector includes the Goldstone bosons and other states such as massive scalar
partners. The second includes a parity-degenerate vector and axial vector along
with other possible parity partners. We note that if such a near-critical
theory describes symmetry breaking in the electroweak theory, the additional
symmetry suppresses the contribution of the parity doubled sector to the S
parameter.


title: Higgs as a Slepton

abstract:
  In theories with TeV scale quantum gravity there is a logical possibility
where the electroweak Higgs can be a fourth generation slepton. Despite maximal
supersymmetry breaking such a scenario turns out to be tightly constrained, and
might be testable already at present collider experiments. Also, a light Higgs
is no longer a prediction of supersymmetry.


title: Technihadron Production and Decay at LEP2

abstract:
  The simple "straw-man" model of low-scale technicolor contains light
color--singlet technihadrons, which mix with the electroweak gauge bosons. We
present lepton collider production rates at the parton level, and show that
experiments at LEP2 may be sensitive to the presence of technirho and
techniomega states with masses 10-20 GeV beyond the center-of-mass energy
because of the mixing. The exact sensitivity depends on several parameters,
such as the technipion mass, the technipion mixing angle, and the charge of the
technifermions. In an appendix, we describe the implementation of the model
into the event generator PYTHIA for particle-level studies at lepton and hadron
colliders.


title:
Inclusive Decays of Bottom Hadrons in New Formulation of Heavy Quark
  Effective Field Theory

abstract:
  We apply the new formulation of heavy quark effective field theory (HQEFT) to
the inclusive decays of bottom hadrons. The long-term ambiguity of using heavy
quark mass or heavy hadron mass for inclusive decays is clarified within the
framework of the new formulation of HQEFT. The $1/m_b$ order corrections are
absent and contributions from $1/m_b^2$ terms are calculated in detail. This
enables us to reliably extract the important CKM matrix element $|V_{cb}|$ from
the inclusive semileptonic decay rates. The resulting lifetime ratios
$\tau(B^0_s)/\tau(B^0)$ and $\tau(\Lambda_b)/\tau(B^0)$ are found to well agree
with the experimental data. We also calculate in detail the inclusive
semileptonic branching ratios and the ratios of the $\tau$ and $\beta$ decay
rates as well as the charm countings in the $B^0$, $B^0_s$ and $\Lambda_b$
systems. For $B^0$ decays, all the observables are found to be consistent with
the experimental data. More precise data for the $B^0$ decays and further
experimental measurements for the $B^0_s$ and $\Lambda_b$ systems will be very
useful for testing the framework of new formulation of HQEFT at the level of
higher order corrections.


title: Trimuon production in \nu N-scattering as a probe of massive neutrinos

abstract:
  The lepton-number violating process \nu_\mu N \to \mu^- \mu^+ \mu^+ X is
studied for the first time in connection with Majorana neutrino masses of the
second generation. The sensitivity for light and heavy Majorana neutrinos is
investigated. The ratio with respect to the standard model charged current
process is improved by some orders of magnitude if compared to previously
discussed Majorana induced \Delta L_{\mu} = 2 processes. Non-observation of
this process in previous experiments allows to demand the effective mass to be
< m_{\mu \mu} > \ls 10^4 GeV, being more stringent than previously discussed
direct bounds, however still unnaturally high. Therefore, in the forseeable
future, indirect bounds on effective masses other than m_{ee} will be more
stringent.


title:
A convergent scheme for one-loop evolutions of the Yukawa couplings in
  the MSSM

abstract:
  Integrated forms of the one-loop evolution equations are given for the Yukawa
couplings in the MSSM, valid for any value of $\tan \beta$, generalizable to
virtually any number of Yukawa fermions, and including all gauge couplings.
These forms turn out to have nice mathematical convergence properties which we
prove, and we determine the ensuing convergence criteria. Furthermore, they
allow to write down general sufficient and necessary conditions to avoid
singularities in the evolution of the Yukawa couplings over physically relevant
energy ranges. We also comment briefly on the possible use of these features
for physics issues and give a short numerical illustration.


title:
Implications of Neutrino Masses on the $K_{L}\to\pi^{0}\nu\bar{\nu}$
  Decay

abstract:
  We calculate the different contributions to the decay $K_{L}\to \pi ^{0}\nu
\bar{\nu}$ that arise if the neutrinos are massive. In spite of a chiral
enhancement factor, we find that these contributions are negligibly small.
Compared to the CP violating leading contributions, the CP conserving
contributions related to Dirac masses are suppressed by a factor of order $(m_K
m_\nu/m_W^2)^2\lesssim10^{-12}$, and those related to Majorana masses are
suppressed by a factor of order $(\alpha_W m_K m_s^2
m_\nu/m_W^4)^2\lesssim10^{-29}$. With lepton flavor mixing we find new
contributions with a single CP violating coupling leading to a final CP even
state or with two CP violating couplings leading to a final CP odd state. These
contributions can be of the order of the Standard Model CP conserving
contributions to the flavor diagonal modes.


title: Testing Top-Quark Yukawa Interactions in e+ e- -> t \bar{t} Z

abstract:
  Determination of the top-quark Yukawa couplings in the process e+ e- -> t
\bar{t} Z has been studied for the high luminosity option (\int L=500\fbinver)
of a linear e+e- collider. Polarization of the electron beam has been
considered. The method of optimal observables has been adopted to determine the
couplings and to disentangle different models. It has been found that it could
be possible to discriminate between the Standard Model scalar Higgs boson, pure
pseudoscalar and the Higgs boson of mixed CP at about 12 \sigma level for
\sqrt{s}=1.TeV for the Higgs boson close to the production threshold both for
the leptonic and hadronic top-quark decay channels. However, \sqrt{s}=.5 TeV
collider turned out to have too small energy for tests of the top-quark Yukawa
coupling because of its limited production rate (at most 2.5 \sigma effect).
Possible tests of CP violation in the scalar sector have been considered.


title: Z radiation off stops at a linear collider

abstract:
  We calculate e+e- --> stop/stop/Z at a linear collider. For large splitting
between the two stops the cross-section is sensitive to the value of m(stop2)
when this particle is too heavy to be directly produced. The results are
compared to e+e- --> stop/stop/h.


title: A Rotated Skyrmion and Pions-Nucleon Interactions

abstract:
  It was shown by careful consideration of the time--dependent classic solution
for the rotated skyrmion, that such solution at large distances has radiational
component similar to the Lienart-Viehart retarded potential in Electrodynamics.
We consider such solution as stationary phase configuration of the pion field
in path integrals for the correlators of $n$ isovector axial currents
$J_{\mu}^{A,i}$ and two nucleon currents $J_N$. $n$ pion -- nucleon amplitudes
are extracted from these correlators. The careful account of the asymptotics of
this stationary phase configuration of the pion field (rotated skyrmion) in
path integral leads to nonzero contribution of this classical part of the total
pion field to pion-nucleon amplitudes. In result, this approach correctly
reproduce pions -- nucleon amplitudes(with the Born -- diagrams contributions,
too).


title:
Parton saturation, production, and equilibration in high energy nuclear
  collisions

abstract:
  Deeply inelastic scattering of electrons off nuclei can determine whether
parton distributions saturate at HERA energies. If so, this phenomenon will
also tell us a great deal about how particles are produced, and whether they
equilibrate, in high energy nuclear collisions.


title: Color Octet Contribution to J/psi Photoproduction Asymmetries

abstract:
  We investigate $J/\psi$ photoproduction asymmetries in the framework of the
NRQCD factorization approach. It is shown that the color octet contribution
leads to large uncertainties in the predicted asymmetries which rules out the
possibility to precisely measure the gluon polarization in the nucleon through
this final state. For small values of the color octet parameters being
compatible with $J/\psi$ photoproduction data it appears possible that a
measurement of $J/\psi$ asymmetries could provide a new test for the NRQCD
factorization approach, on one hand, or a measurement of the polarized gluon
distribution from low inelasticity events $(z<0.7)$, on the other


title:
Sparticle Mass Spectra from SO(10) Grand Unified Models with Yukawa
  Coupling Unification

abstract:
  We examine the spectrum of superparticles obtained from the minimal SO(10)
grand unified model, where it is assumed the gauge symmetry breaking yields the
Minimal Supersymmetric Standard Model (MSSM) as the effective theory at
$M_{GUT}\sim 2\times 10^{16}$ GeV. In this model, unification of Yukawa
couplings implies a value of $\tan\beta\sim 45-55$. At such high values of
$\tan\beta$, assuming universality of scalar masses, the usual mechanism of
radiative electroweak symmetry breaking breaks down. We show that a set of weak
scale sparticle masses consistent with radiative electroweak symmetry breaking
can be generated by imposing non-universal GUT scale scalar masses consistent
with universality within SO(10) plus extra $D$-term contributions associated
with the reduction in rank of the gauge symmetry group when SO(10)
spontaneously breaks to $SU(3)\times SU(2)\times U(1)$. We comment upon the
consequences of the sparticle mass spectrum for collider searches for
supersymmetry. One implication of SO(10) unification is that the light bottom
squark can be by far the lightest of the squarks. This motivates a dedicated
search for bottom squark pair production at $p\bar{p}$ and $e^+e^-$ colliders.


title: Large magnetic dipole moments for neutrinos with arbitrary masses

abstract:
  We show that there is a general sort of models in which it is possible to
have large magnetic dipole moments for neutrinos while keeping their masses
arbitrarily small. Some examples of these models are considered.


title: Natural fermion mass hierarchy and new signals for the Higgs boson

abstract:
  We suggest a novel approach towards resolving the fermion mass hierarchy
problem within the framework of the Standard Model. It is shown that the
observed masses and mixings can be explained with order one couplings using
successive higher dimensional operators involving the SM Higgs doublet field.
This scenario predicts flavor-dependent enhancement in the the Higgs boson
coupling to the fermions (by a factor of 3 to the b-quark and \tau and by a
factor of 5 to \mu relative to the SM). It also predicts flavor changing
\bar{t}ch^0 interaction with a strength comparable to that of \bar{b}bh^0. This
opens up a new discovery channel for the Higgs boson at the upgraded Tevatron
and the LHC through t -> ch^0 or h^0 -> \bar{t}c + \bar{c}t. Additional tests
of the framework include D^0-\bar{D^0} mixing which is predicted to be near the
current experimental limit and a host of new phenomena associated with flavor
physics at the TeV scale.


title:
Perturbative Pion Wave function in Coherent Pion-Nucleon Di-Jet
  Production

abstract:
  A perturbative QCD treatment of the pion wave function is applied to
computing the scattering amplitude for coherent high relative momentum di-jet
production from a nucleon.


title:
A Poincar\'e-Covariant Parton Cascade Model for Ultrarelativistic
  Heavy-Ion Reactions

abstract:
  We present a new cascade-type microscopic simulation of Nucleus-Nucleus
Collisions at RHIC energies. The basic elements are partons (quarks and gluons)
moving in 8N-dimensional phase space according to Poincar\'e-covariant
dynamics. The parton-parton scattering cross sections used in the model are
computed within perturbative QCD in the tree-level approximation. The $Q^2$
dependence of the structure functions is included by an implementation of the
DGLAP mechanism suitable for a cascade, so that the number of partons is not
static, but varies in space and time as the collision of two nuclei evolves.
The resulting parton distributions are presented and compared to distributions
obtained with the VNI model.


title: Neutrino Mixing and Oscillations in 1999 and Beyond

abstract:
  The interpretation of the existing experimental evidences for oscillations of
neutrinos in schemes with three and four neutrino mixing is reviewed. Forms of
the lepton mixing matrix allowed by the neutrino oscillation data are
considered. The possible neutrino mass spectra compatible with the observations
are analyzed. The possibility to obtain information about the neutrino mass
spectrum from the future $^{3}$H $\beta-$decay and $(\beta \beta)_{0\nu}-$decay
experiments is also considered.


title: Glueball Production in Peripheral Heavy-Ion Collisions

abstract:
  The method of equivalent quanta is applied both to photon-photon and, by
analogy, to double pomeron exchange in heavy-ion collisions. This
Weizs\"acker-Williams approach is used to calculate production cross sections
for the glueball candidate $f_J(1710)$ meson via photon-photon and
pomeron-pomeron fusion in peripheral heavy-ion collisions at both RHIC and LHC
energies. The impact-parameter dependence for total and elastic cross sections
are presented, and are compared to results for proton-proton collisions.


title: Bulk Fields in the Randall-Sundrum Compactification Scenario

abstract:
  Recently, Randall and Sundrum proposed a solution to the hierarchy problem
where the background spacetime is five dimensional. There are two 3-branes, and
the mass scale for fields that propagate on one of the 3-branes is
exponentially suppressed relative to the fundamental scale of theory, which is
taken to be the Planck mass, M_Pl. In this letter we show that bulk fields with
a five dimensional mass term of order M_Pl have, after integrating over the
extra dimension, modes with four-dimensional masses that are exponentially
suppressed as well. This opens the possibility that in this scenario the
Standard Model matter fields may correspond to degrees of freedom that are not
confined to a 3-brane.


title:
Diminishing "charginos nearly degenerate with the lightest neutralino"
  slit using precision data

abstract:
  Though LEP II direct searches still cannot exclude a chargino nearly
degenerate with the lightest neutralino if their mass is only slightly above
half of the Z boson mass, it can be excluded indirectly analyzing precision
data. In this particular limit simple analytical formulas for oblique
electroweak radiative corrections are presented.


title:
The decay $b\to s\gamma$ and the charged Higgs boson mass without
  R-Parity

abstract:
  The experimental measurement of $B(b \to s\gamma)$ imposes important
constraints on the charged Higgs boson mass in the MSSM. We show that by adding
bilinear R--Parity violation (BRpV) in the tau sector, these bounds are
relaxed. The bound on $m_{H^{\pm}}$ in the MSSM--BRpV model is $\gsim 200-250$
GeV for the the heavy squark limit. For lighter squarks, light charged Higgs
bosons can be reconciled with $B(b \to s\gamma)$ only if there is also a light
chargino. In the BRpV model if we impose $m_{\chi^{\pm}_1}>90$ GeV $m_{H^{\pm}}
\gsim 75$ GeV, around 30 GeV down from the MSSM. In this case the charged Higgs
bosons would be observable at LEP II. The relaxation of the bounds is due
mainly to the fact that charged Higgs bosons mix with staus and they contribute
importantly to $B(b \to s\gamma)$.


title: Future Small x Physics with ep and eA Colliders

abstract:
  The interaction of spatially small dipoles with nucleons, nuclei is
calculated in the DGLAP approximation at the top of HERA energies and found to
be close to the $S$-channel unitarity limit in the case of the color octet
dipoles. The DGLAP analyses of the current diffractive data appear to support
this conclusion as they indicate a $\sim 30-40%$ probability of the gluon
induced diffraction for $Q^2\sim 4 $GeV$^2$. The need for the high-precision
measurements of the $t$-dependence of inclusive and exclusive diffraction for
pinpointing higher twist effects in the gluon sector is emphasized.The $eA$
collisions at HERA would provide a strong amplification of the gluon densities
allowing to reach deep into the regime of nonlinear QCD evolution. Connection
between the leading twist nuclear shadowing and leading twist diffraction in
$ep$ scattering is explained. The presented model independent results for the
nuclear shadowing for light nuclei indicate much larger shadowing for the gluon
sector than for the sea quark sector.It is argued that HERA in $eA$ mode would
be able to discover a number of new phenomena including large gluon shadowing,
large nonlinearities in parton evolution, small $x$ color transparency in the
vector meson production followed by color opacity at $x\le .005$, large
probability of inclusive diffraction. Implications for the nucleus-nucleus
collisions at LHC are discussed as well.


title: Neutrino Mass: theory, data and interpretation

abstract:
  In these two lectures I describe first the theory of neutrino mass and then
discuss the implications of recent data (including 708--day data
Super--Kamiokande data) which strongly indicate the need for neutrino
conversions to account for the solar and atmospheric neutrino observations. I
also mention the LSND data, which provides an intriguing hint. The simplest
ways to reconcile all these data in terms of neutrino oscillations invoke a
light sterile neutrino in addition to the three active ones. Out of the four
neutrinos, two are maximally-mixed and lie at the LSND scale, while the others
are at the solar mass scale. These schemes can be distinguished at
neutral-current-sensitive solar & atmospheric neutrino experiments. I discuss
the simplest theoretical scenarios, where the lightness of the sterile
neutrino, the nearly maximal atmospheric neutrino mixing, and the generation of
$\Delta {m^2}_\odot$ & $\Delta {m^2}_{atm}$ all follow naturally from the
assumed lepton-number symmetry and its breaking. Although the most likely
interpretation of the present data is in terms of neutrino-mass-induced
oscillations, one still has room for alternative explanations, such as flavour
changing neutrino interactions, with no need for neutrino mass or mixing. Such
flavour violating transitions arise in theories with strictly massless
neutrinos, and may lead to other sizeable flavour non-conservation effects,
such as $\mu \to e + \gamma$, $\mu-e$ conversion in nuclei, unaccompanied by
neutrino-less double beta decay.


title:
Late D-term Inflation and the Cosmological Moduli Problem in TeV Scale
  Strings

abstract:
  We show that a short period of late D-term inflation can solve the
cosmological moduli (radion) problem of (asymmetric) inflation at the TeV
scale. Late inflation happens after the large compact dimensions are stabilized
which is crucial for obtaining the extremely small Hubble constant and inflaton
mass required.


title: Quark Structure of $\Lambda$ from $\Lambda$-Polarization in Z Decays

abstract:
  The flavor and spin structure for the quark distributions of the
$\Lambda$-baryon is studied in a perturbative QCD (pQCD) analysis and in the
SU(6) quark-diquark model, and then applied to calculate the
$\Lambda$-polarization of semi-inclusive $\Lambda$ production in
$e^+e^-$-annihilation near the $Z$-pole. It is found that the quark-diquark
model gives very good description of the available experimental data. The pQCD
model can also give good description of the data by taking into account the
suppression of quark helicities compared to the naive SU(6) quark model spin
distributions. Further information is required for a clean distinction between
different predictions concerning the flavor and spin structure of the
$\Lambda$.


title: The semileptonic B->pi decay in a Constituent Quark-Meson model

abstract:
  We evaluate the form factors describing the exclusive decay B-> pi l nu by
using a Constituent Quark-Meson model based on an effective quark-meson
Lagrangian (CQM). The model allows for an expansion in the pion momenta and we
consider terms up to the first order in the pion field derivatives. We compute
the leading terms in the soft pion limit and consider corrections to this
limit.


title:
Phenomenology of eta-gamma and eta'-gamma transition form factors at
  large momentum transfer

abstract:
  I discuss the progress in our theoretical understanding of the eta-gamma and
eta'-gamma transition form factors, including the recent data from CLEO and L3
at large momentum transfer, Q^2. The experimental data above Q^2=1 GeV^2 can be
well described by the hard scattering approach if the distribution amplitudes
for eta and eta' mesons are taken close to the asymptotic one. Particular
attention is paid to the interpretation of the data in terms of properly
defined eta-eta' mixing parameters. I also comment on the use and misuse of
interpolation formulas for P-gamma and P-gamma^* transition form factors.


title:
Dispersive and chiral symmetry constraints on the light meson form
  factors

abstract:
  The form factors of the light pseudoscalar mesons are investigated in a
dispersive formalism based on hadronic unitarity, analyticity and the OPE
expansion of the QCD Green functions. We propose generalizations of the
original mathematical techniques, suitable for including additional low energy
information provided by experiment or Chiral Perturbation Theory (CHPT). The
simultaneous treatment of the electroweak form factors of the $\pi$ and $K$
mesons allows us to test the consistency with QCD of a low energy CHPT theorem.
By applying the formalism to the pion electromagnetic form factor, we derive
quite strong constraints on the higher Taylor coefficients at zero momentum,
using information about the phase and the modulus of the form factor along a
part of the unitarity cut.


title:
Optimized Lambda-Parametrization for the QCD Running Coupling Constant
  in Spacelike and Timelike Regions

abstract:
  The algorithm is described that enables one to perform an explicit summation
of all the (\pi^2/ ln(Q^2/Lambda^2))^N corrections to \alpha_s (Q^2) that
appear owing to the analytic continuation from spacelike to timelike region of
momentum transfer.


title:
The hard bremsstrahlung correction to e^+ e^- -> 4f with finite fermion
  masses: results for e^+ e^- -> u d-bar mu^- nu

abstract:
  An improved efficient method of calculating the hard bremsstrahlung
correction to e^+ e^- -> 4f for non-zero fermion masses is presented. The
non-vanishing fermion masses allow us to perform the phase space integrations
to the very collinear limit. We therefore can calculate cross sections
independent of angular cuts. Such calculations are important for background
studies. Results are presented for the total and some differential cross
sections for e^+ e^- -> u d-bar mu^- nu and the corresponding hard
bremsstrahlung process. The latter is of particular interest for a detailed
investigation of the effects of final state radiation. In principle, the
process e^+ e^- -> u d-bar mu^- nu gamma is also interesting since it helps to
set bounds on possible anomalous triple and quartic gauge boson couplings
involving photons. The size of mass effects is illustrated by comparing the
final states u d-bar mu^- nu (gamma), c s-bar mu^- nu (gamma) and u d-bar tau^-
nu(gamma).


title: Violation of supersymmetric equivalence in R parity violating couplings

abstract:
  In this paper we consider the violation of supersymmetric equvalence among
the R parity violating couplings $lamabda_{ijk}$ caused by widely split chiral
supermultiplets. We find that if $\lambda^{\prime}_{2jk}=g$ and
$\lambda^{\prime}_{1jk}=e$ then the violation of SUSY equivalence is of the
order of $5-6%$ in heavy SQCD models. On the other hand if
$\lambda^{\prime}_{3jk}=g$ and $\lambda_{ijk}=e$ then the violation of SUSY
equivalence can be as large as 9.4% in 2-1 models.


title: Parton Distributions and the LHC: W and Z Production

abstract:
  W and Z bosons will be produced copiously at the LHC proton-proton collider.
We study the parton distribution dependence of the total production cross
sections and rapidity distributions, paying particular attention to the
uncertainties arising from uncertainties in the parton distributions
themselves. Variations in the gluon, the strong coupling, the sea quarks and
the overall normalisation are shown to lead to small but non-negligible
variations in the cross section predictions. Ultimately, therefore, the
measurement of these cross sections will provide a powerful cross check on our
knowledge of parton distributions and their evolution.


title:
Cottingham formula and the pion electromagnetic mass difference at
  finite temperature

abstract:
  We generalize the Cottingham formula at finite (T\neq 0) temperature by using
the imaginary time formalism. The Cottingham formula gives the theoretical
framework to compute the electromagnetic mass differences of the hadrons using
a dispersion relation approach. It can be also used in other contexts, such as
non leptonic weak decays, and its generalization to finite temperature might be
useful in evaluating thermal effects in these processes. As an application we
compute the \pi^+-\pi^0 mass difference at T\neq 0; at small T we reproduce the
behaviour found by other authors: \delta m^2(T)= \delta
m^2(0)+\mathcal{O}(\alpha T^2), while for moderate T, near the deconfinement
temperature, we observe deviations from this behaviour.


title: The Radiative Decay of Vector Mesons

abstract:
  In this paper, radiative decays $\rho^0 \to \pi^+\pi^-\gamma,
\pi^0\pi^0\gamma$ ,$\phi \to K^+K^-\gamma, K^0 \bar{K^0}\gamma$ are studied
systematically in the U(3)$_L\timesU(3)_R$ chiral theory of mesons. The
theoretical differential spectrum with respect to photon energy and branch
ratio for $\rho^0 \to \pi^+\pi^-\gamma$ agree well with the experimental data.
Differential spectrums and branch ratios for $\rho^0 \to \pi^0\pi^0\gamma, \phi
\to K^+ K^-\gamma,\phi \to K^0\bar{K^0}\gamma$ are predicted. The process $\phi
\to K^0 \bar{K^0} \gamma$ is relevant to precision measurment of CP-violation
parameters in the kaon systerm at a $\phi$-factory. We give a complete estimate
of the branch ratio for this decay process by including scalar resonance $f_0,
a_0$ poles, nonresonant smooth amplitude and an abnormal parity process with
$K^*$ pole which hasn't been considered before. We conclude that processes with
intermediate $K^*$ do not pose a potential background problem for $\phi\to
K^0\bar{K}^0$ CP violation experiments.


title:
Constraints from Neutrino Oscillation Experiments on the Effective
  Majorana Mass in Neutrinoless Double $\beta$-Decay

abstract:
  We determine the possible values of the effective Majorana neutrino mass $|<
m > |= |\sum_j U_{ej}^2 m_j|$ in the different phenomenologically viable three
and four-neutrino scenarios. The quantities $U_{\alpha j}$ ($\alpha =
e,\mu,\tau,...$) denote the elements of the neutrino mixing matrix and the
Majorana neutrino masses $m_j$ ($j=1,2,3,...$) are ordered as $m_1 < m_2 < ...
$ Assuming $m_1 \ll m_3$ in the three-neutrino case and $m_1 \ll m_4$ in the
four-neutrino case, we discuss, in particular, how constraints on $| < m > |$
depend on the mixing angle relevant in solar neutrino oscillations and on the
three mass-squared differences obtained from the analyses of the solar,
atmospheric and LSND data. If neutrinoless double $\beta$-decay proceeds via
the mechanism involving $|< m >|$, conclusions about neutrinoless double
$\beta$-decay can be drawn. If one of the two viable four-neutrino schemes
(Scheme A) is realized in nature, $|< m >|$ can be as large as 1 eV and
neutrinoless double $\beta$-decay could possibly be discovered in the near
future. In this case a Majorana CP phase of the mixing matrix $U$ could be
determined. In the other four-neutrino scheme (Scheme B) there is an upper
bound on $|< m >|$ of the order of $10^{-2}$ eV. In the case of three-neutrino
mixing the same is true if the neutrino mass spectrum is hierarchical, however,
if there exist two quasi-degenerate neutrinos and the first neutrino has a much
smaller mass, values of $|< m >|$ as large as $\sim 0.1$ eV are possible.


title:
Anomalous Quartic Couplings in $\nu \bar{\nu} \gamma \gamma$ Production
  via WW-Fusion at LEP2

abstract:
  The production of $\nu \bar{\nu} \gamma \gamma$ in high-energy $e^+e^-$
collisions offers a window on anomalous quartic gauge boson couplings. We
investigate the effect of two possible anomalous couplings on the cross section
for $\nu \bar{\nu} \gamma \gamma$ production via $WW$-fusion at LEP2 ($\sqrt{s}
= 200$ GeV).


title: On the Dirac monopole's concept

abstract:
  The Dirac monopole is discussed in view of the gauge invariance in Quantum
Electrodynamics. It is shown the monopole existence implies the violation of
the gauge invariance principle. The monopole field is essentially a
longitudinal field and so a mass is naturally associated to it. Interpretation
for the case the monopole charge is different from zero is addressed at the
conclusion.


title: Higgs Boson Production at the Compton Collider

abstract:
  The high precision determination of the partial width $\Gamma (H
\longrightarrow \gamma \gamma)$ of an intermediate mass Higgs boson is among
the most important measurements at a future photon--photon collider. Recently
it was shown that large non-Sudakov as well as Sudakov double logarithmic
corrections can be summed to all orders in the background process $\gamma
\gamma \longrightarrow q \bar{q}$, $q=\{b,c\}$, from an initially polarized
$J_z=0$ state. In addition, running coupling corrections were included exactly
to all orders by employing the renormalization group. Thus all necessary
theoretical results for calculating the Higgs signal and the non-Higgs
continuum background contributions to the process $\gamma \gamma
\longrightarrow q \bar{q}$ are now known. We are therefore able to present for
the first time precise predictions for the measurement of the partial width
$\Gamma (H \longrightarrow \gamma \gamma)$ at the Compton collider
($\gamma\gamma$) option at a future linear $e^+e^-$ collider. The interplay
between signal and background is very sensitive to the experimental cuts and
the ability of the detectors to identify $b$-quarks in the final state. We
investigate this in some detail using a Monte Carlo analysis, and conclude that
a measurement with a 2 % statistical accuracy should be achievable. This could
have important consequences for the discovery of physics beyond the Standard
Model, in particular for large masses of a pseudoscalar Higgs boson as the
decoupling limit is difficult and for a wide range of $\tan \beta$ impossible
to cover at the LHC proton-proton collider.


title:
Structure of physical space and new interaction in nature (theory and
  experiments)

abstract:
  In the talk, on the basis of the author's model of formation of the
observable physical space $R_3$ in the process of dynamics of special discrete
one-dimensional vectorial objects, byuons, while minimizing their potential
energy of interaction in the one-dimensional space $R_1$ formed by them, the
existence of global anisotropy of observable space and new interaction in
nature, is shown. The data of recent experiments are given and discussed.


title: Potential NRQCD: an effective theory for heavy quarkonium

abstract:
  Within an effective field theory framework we study heavy-quark--antiquark
systems with a typical distance between the heavy quark and the antiquark
smaller than $1/\Lambda_{\rm QCD}$. A suitable definition of the potential is
given within this framework, while non-potential (retardation) effects are
taken into account in a systematic way. We explore different physical systems.
Model-independent results on the short distance behavior of the energies of the
gluonic excitations between static quarks are obtained. Finally, we show how
infrared renormalons affecting the static potential get cancelled in the
effective theory.


title: Seeking the Shadowing in eA Processes

abstract:
  We consider the behavior of the slope of the nuclear structure function
$F_2^A$ in the kinematic region which will be explored in the eA HERA collider.
We demonstrate that, similarly to the nucleon case, a `turn over' is predicted
in this observable. Moreover, we predict that the presence of the shadowing
corrections implies that the maximum value of the slope is dependent of the
number of nucleons A, differently from the DGLAP predictions. Our conclusion is
that the measurement of this observable will allow to evidentiate the presence
of the shadowing corrections.


title:
Radiation Zeros as an Observable to test Physics beyond the Standard
  Model

abstract:
  The vanishing of the cross section for particular points in phase space -
radiation zeros - is examined for the process $ q \bar q \to W^+W^- \gamma$ at
high energy. For photon energies that are not too large, the cross section does
exhibit deep dips in regions of phase space corresponding to the position of
the actual zeros. We show that in these regions the sensitivity to possible
anomalous quartic couplings is very large.


title: Precision Flavour Physics and Supersymmetry

abstract:
  We review the salient features of a comparative study of the profile of the
CKM unitarity triangle, and the resulting CP-violating phases $\alpha$, $\beta$
and $\gamma$ in B decays, in the standard model and in several variants of the
minimal supersymmetric standard model (MSSM), reported recently by us. These
theories are characterized by a single phase in the quark flavour mixing matrix
and give rise to well-defined contributions in the
flavour-changing-neutral-current transitions in K and B decays. We analyse the
supersymmetric contributions to the mass differences in the Bd-Bd(bar) and
Bs-Bs(bar) systems, $\Delta M_d$ and $\Delta M_s$, respectively, and to the
CP-violating quantity $|epsilon|$ in K decays. Our analysis shows that the
predicted ranges of $\beta$ in the standard model and in MSSM models are very
similar. However, precise measurements at B-factories and hadron machines may
be able to distinguish these theories in terms of the other two CP-violating
phases $\alpha$ and $\gamma$.
  (Contribution to the Festschrift for L.B. Okun, to appear in a special issue
of Physics Reports, eds. V.L. Telegdi and K. Winter)


title: String theoretic axion coupling and the evolution of cosmic structures

abstract:
  We examine the effects of the axion coupling to $R\tilde{R}$ on the evolution
of cosmic structures. It is shown that the evolutions of the scalar- and
vector-type perturbations are not affected by this axion coupling. However the
axion coupling causes an asymmetric evolution of the two polarization states of
the tensor-type perturbation, which may lead to a sizable polarization
asymmetry in the cosmological gravitational wave if inflation involves a period
in which the axion coupling is important. The polarization asymmetry produced
during inflation are conserved over the subsequent evolution as long as the
scales remain in the large-scale limit, and thus this may lead to an observable
trace in the cosmic microwave background radiation.


title: Jet Production by Virtual Photons

abstract:
  The production of jets is studied in collisions of virtual photons, gamma*-p
and gamma*-gamma*, specifically for applications at HERA and LEP2. Photon flux
factors are convoluted with matrix elements involving either direct or resolved
photons and, for the latter, with parton distributions of the photon. Special
emphasis is put on the range of uncertainty in the modeling of the resolved
component. The resulting model is compared with existing data.


title: Flux tube dynamics in the dual superconductor

abstract:
  We have studied plasma oscillations in a flux tube created in a dual
superconductor. Starting from a static flux tube configuration, with electric
charges at either end, we release a fluid of electric charges in the system
that accelerate and screen the electric field. The weakening of the electric
field allows the flux tube to collapse, and the inertia of the charges forces
it open again. We find strong radiation of electric flux into the
superconductor in all regimes of couplings.


title: Screening in Hot Non-Abelian Plasma

abstract:
  This thesis is devoted to the study of the screening masses in hot
non-Abelian theories. Section 1 contain a brief introduction to the topic. In
section 2 a detailed overview of the screening phenomena and their applications
is given. In section 3 the screening masses are defined through the coupled gap
equations. Section 4 deals with the determination of the screening masses of
hot SU(2) gauge theory in the framework of the 3d lattice adjoint Higgs model
considered as an effective theory. Finally in section 5 the screening masses of
hot SU(2) Higgs model are examined.


title: QED corrections to DIS with a tagged photon at HERA

abstract:
  We report on the calculation of the QED radiative corrections to deep
inelastic scattering with a tagged photon with next-to-leading logarithmic
accuracy. Numerical results are given for different experimental setups for the
case of the HERA collider.


title:
Charge and Magnetic Moment of the Neutrino in the Background Field
  Method and in the Linear R_xi^L Gauge

abstract:
  We present a computation of the charge and the magnetic moment of the
neutrino in the recently developed electro-weak Background Field Method and in
the linear $R_{\xi}^L$ gauge. First, we deduce a formal Ward-Takahashi identity
which implies the immediate cancellation of the neutrino electric charge. This
Ward-Takahashi identity is as simple as that for QED. The computation of the
(proper and improper) one loop vertex diagrams contributing to the neutrino
electric charge is also presented in an arbitrary gauge, checking in this way
the Ward-Takahashi identity previously obtained. Finally, the calculation of
the magnetic moment of the neutrino, in the minimal extension of the Standard
Model with massive Dirac neutrinos, is presented, showing its gauge parameter
and gauge structure independence explicitly.


title: A possible alternative to the Breit frame in DIS

abstract: A new Lorentz frame for DIS jet finding is suggested.


title: Parton Content of Real and Virtual Photons

abstract:
  Parameter-free and perturbatively stable leading order (LO) and
next-to-leading order (NLO) parton densities for real and virtual photons are
presented.


title: Direct CP violation in semi-leptonic and leptonic decays

abstract:
  We show that direct CP violation in semi-leptonic and leptonic decays can
occur in multi-Higgs doublet extensions of the electroweak standard model with
flavor changing neutral currents. For pion and lepton decays these $CP$
violating effects cannot be constrained directly by experimental data since up
to now the branching ratio of the decays $\pi^-$ and $\mu^-$ have not been
measured in laboratory.


title:
Neutrino Spin-Flavor Conversions and Electron Antineutrino emission from
  the Sun with Random Magnetic Field

abstract:
  The magnetic field in the solar convective zone has a random small-scale
component with the r.m.s. value substancially exceeding the strength of a
regular large-scale field. For two Majorana neutrino flavors and two helicities
in the presence of a neutrino transition magnetic moment and nonzero neutrino
mixing we analize the displacement of the allowed (Delta m^2 - sin^2
2theta)-parameter region reconciled for all Underground experiments with solar
neutrinos in dependence on the r.m.s. magnetic field value b. In contrary with
the RSFP scenario with a regular large-scale magnetic field, we find an
effective production of electron antineutrinos in the Sun even for small
neutrino mixing through the cascade conversions like nu_eL -> \bar{nu}_muR ->
\bar{nu}_eR. It was found that usual SMA and LMA MSW parameter regions maybe
forbidden while opening LOW MSW as the allowed one from the non-observation of
\bar{nu}_eR in the SK experiment if random magnetic fields have strengths b >
100 kG and correlation lengths shorter than L_0 < 1000 km.


title: The Nielsen Identities of the SM and the definition of mass

abstract:
  In a generic gauge theory the gauge parameter dependence of individual Green
functions is controlled by the Nielsen identities, which originate from an
enlarged BRST symmetry. We give a practical introduction to the Nielsen
identities of the Standard Model (SM) and to their renormalization and
illustrate the power of this elegant formalism in the case of the problem of
the definition of mass.We prove to all orders in perturbation theory the
gauge-independence of the complex pole of the propagator for all physical
fields of the SM, in the most general case with mixing and CP violation. At the
amplitude level, the formalism provides an intuitive and general understanding
of the gauge recombinations which makes it particularly useful at higher
orders. We also include in an appendix the explicit expressions for the
fermionic two-point functions in a generic R_\xi gauge.


title: RG invariant solutions for the soft supersymmetry breaking parameters

abstract:
  We show that the results for the soft couplings in supersymmetric gauge
theories recently derived via the superconformal anomaly are equivalent to
results obtained earlier from a consideration of exact RG-invariant
trajectories. We give a full proof of these results for a general
multi-coupling theory. Moreover, we demonstrate the existence of a distinct
finite RG-invariant solution for the soft couplings in the case when the
unbroken supersymmetric theory is finite.


title: Observability of B_(d)s-> mu mu decay with the CMS detector

abstract:
  We have updated our previous study on the possibility to observe the rare
B0_s -> 2mu decay with detailed simulation of the TDR version of the CMS
detector. The full simulation and reconstruction procedure has been done both
for the signal and background. We improved our previous results on expected
sensitivity using more sophisticated algorithms for the track and vertex
reconstruction and tighter selection criteria.


title:
Search for SUSY at LHC in Jets + E^{miss}_T final states for the case of
  nonuniversal gaugino masses

abstract:
  We investigate squark and gluino pair production at LHC (CMS) with subsequent
decays into quarks and LSP for the case of nonuniversal gaugino masses.
Visibility of signal by an excess over SM background in (n > 1)jets +
E^{miss}_T events depends rather strongly on the relation between LSP, gluino
and squark masses and it decreases with the increase of LSP mass. For
relatively heavy LSP mass closed to squark or gluino masses and for
(m_{\tilde{q}}, m_{\tilde{g}}) > 1.5 TeV signal is too small to be observable.
For the case when only third generation squarks and LSP are relatively light
signal is not visible without b-tagging.


title:
Stringy Model for QCD at Finite Density and Generalized Hagedorn
  Temperature

abstract:
  Using generic properties of string theories, we show how interesting
non-perturbative features of QCD can be exploited in heavy ion collisions. In
particular, a generalized "semi-circle" law for the phase diagram in the
temperature-chemical potential plane is derived.


title: Radial Excitations

abstract:
  In this contribution I review recent experimental developments in the
spectroscopy of higher-mass mesons, especially candidate radial excitations
discussed at the WHS99 meeting in Frascati.


title: Neutral kaons as decay products and analyzers of heavier flavors

abstract:
  Cascade decays of heavy flavor hadrons to states with neutral kaons are
discussed as an instrument for detailed studies of the heavy hadron properties.
For neutral flavored mesons the well-known kaon oscillations provide a unique
experimental possibility of relating lighter/heavier eigenstate masses to
(approximate) even/odd eigenstate CP-parities and to longer/shorter eigenstate
lifetimes. As a result, they allow to eliminate sign ambiguities of
CP-violating parameters and, therefore, to check the Standard Model (or to find
New Physics). Specifically for charmed hadrons, both neutral/charged mesons and
baryons, the secondary kaon oscillations permit unambiguous separation of
Cabibbo-allowed and doubly-suppressed decay amplitudes, including measurement
of their relative phases. For neutral $D$-meson decays the kaon oscillations
can also discriminate, again unambiguously, between effects of $D$-meson mixing
and interference of suppressed/allowed amplitudes. Another problem discussed is
the influence of kaon CP-violation on the amplitude structure and on
phenomenology of CP-violation in heavy hadron decays.


title: Supersymmetric Cold Dark Matter with Yukawa Unification

abstract:
  The cosmological relic density of the lightest supersymmetric particle of the
minimal supersymmetric standard model is calculated under the assumption of
gauge and Yukawa coupling unification. We employ radiative electroweak breaking
with universal boundary conditions from gravity-mediated supersymmetry
breaking. Coannihilation of the lightest supersymmetric particle, which turns
out to be an almost pure bino, with the next-to-lightest supersymmetric
particle (the lightest stau) is crucial for reducing its relic density to an
acceptable level. Agreement with the mixed or the pure cold (in the presence of
a nonzero cosmological constant) dark matter scenarios for large scale
structure formation in the universe requires that the lightest stau mass is
about 2-8% larger than the bino mass, which can be as low as 222 GeV. The
smallest allowed value of the lightest stau mass turns out to be about 232 GeV.


title: Cosmological QCD Phase Transition and Dark Matter

abstract:
  We calculate the size distribution of quark nuggets, which could be formed
due to first order QCD phase transition in the early universe. We find that
there are a large number of stable Quark Nuggets which could be a viable
candidate for cosmological dark matter.


title: Hadron masses in cavity quantum chromodynamics to order $\alpha_s^2$

abstract:
  The non-divergent diagrams describing two-gluon exchange and annihilation
between quarks and antiquarks are calculated in the Feynman gauge, based on
quantum chromodynamics in a spherical cavity. Using the experimental $N$,
$\Delta$, $\Omega$, and $\rho$ masses to fit the free parameters of the M.I.T.\
bag model, the predicted states agree very well with the observed low-lying
hadrons. As expected, the two-gluon annihilation graphs lift the degeneracy of
the $\pi$ and $\eta$, while the $\rho$ and $\omega$ remain degenerate.
Diagonalizing the $\eta - \eta'$ subspace Hamiltonian yields a very good value
for the mass of the $\eta$ meson.


title:
Two-point Functions at Two Loops in Three Flavour Chiral Perturbation
  Theory

abstract:
  The vector and axial-vector two-point functions are calculated to
next-to-next-to-leading order in Chiral Perturbation Theory for three light
flavours. We also obtain expressions at the same order for the masses,
$m_\pi^2$, $m_K^2$ and $m_\eta^2$, and the decay constants, $F_\pi$, $F_K$ and
$F_\eta$. We present some numerical results after a simple resonance estimate
of some of the new ${\cal O}(p^6)$ constants.


title:
Semi-inclusive \pi^\pm production - tests for independent fragmentation
  and for polarized quark densities

abstract:
  We show that measurements of semi-inclusive $\pi^\pm$ asymmetries on $p$ and
$n$ with polarized and unpolarized target and beams allow, without any
knowledge of the polarized parton densities 1) to test independent
fragmentation and SU(2) symmetry for the polarized sea, and 2) to determine
separately the polarized strange and valence quark densities, and the ratio of
the fragmentation functions
  $D_s^{\pi^+ + \pi^-}/D_u^{\pi^+ +\pi^-}$


title:
Quark Model and Neutral Strange Secondary Production by Neutrino and
  Antineutrino Beams

abstract:
  The experimental data on $K^0$ and $\Lambda$ production by $\nu$ and
$\bar{\nu}$ beams are compared with the predictions of quark model assuming
that the direct production of secondaries dominates. Disagreement of these
predictions with the data allows one to suppose that there exists considerable
resonance decay contribution to the multiplicities of produced secondaries.