title:
Astrophysical Neutrino Event Rates and Sensitivity for Neutrino
  Telescopes

abstract:
  Spectacular processes in astrophysical sites produce high-energy cosmic rays
which are further accelerated by Fermi-shocks into a power-law spectrum. These,
in passing through radiation fields and matter, produce neutrinos. Neutrino
telescopes are designed with large detection volumes to observe such
astrophysical sources. A large volume is necessary because the fluxes and
cross-sections are small. We estimate various telescopes' sensitivities and
expected event rates from astrophysical sources of high-energy neutrinos. We
find that an ideal detector of km^2 incident area can be sensitive to a flux of
neutrinos integrated over energy from 10^5 and 10^{7} GeV as low as 1.3 *
10^(-8) * E^(-2) (GeV/cm^2 s sr) which is three times smaller than the
Waxman-Bachall conservative upper limit on potential neutrino flux. A real
detector will have degraded performance. Detection from known point sources is
possible but unlikely unless there is prior knowledge of the source location
and neutrino arrival time.


title:
Factorization and Resummation of Small x Scaling Violations with Running
  Coupling

abstract:
  We discuss the inclusion of running coupling effects in perturbative small x
evolution equations. We show that a running coupling BFKL-like x-evolution
equation is fully compatible, up to higher twist corrections, with the standard
factorized perturbative evolution of parton distributions. We then use this
result, combined with the well-known Airy asymptotics, to prove that the
oscillations which are present in the running-coupling BFKL solution do not
affect the associated splitting functions, which instead remain smooth in the
small x limit. This allows us to give a prescription to include
running-coupling corrections in the small-x resummation of scaling violations.
We show that these corrections are small in the HERA region.


title:
Distinguishing Kaluza-Klein Resonances From a $Z'$ in Drell-Yan
  Processes at the LHC

abstract:
  We explore the capability of the LHC to distinguish the production of
Kaluza-Klein(KK) excitations in Drell-Yan collisions from an ordinary $Z'$ at
the LHC in the case of one extra dimension with the fermions localized at the
orbifold fixed points. In particular, we demonstrate that this capability is
dependent on both the mass of the KK state as well as whether or not the quarks
and leptons lie at the same fixed points.


title:
Effects of jet algorithms from higher order QCD in $W^\pm$ mass
  determinations at LEP2

abstract:
  We analyse the impact of systematic effects due to the scale dependence of
QCD corrections in combination with the use of different jet clustering
algorithms in the measurement of the $W^\pm$ mass in the fully hadronic decay
mode of $W^+W^-$ pairs produced at LEP2. We consider higher order contributions
induced by both virtual and real gluon radiation onto the electroweak CC03 and
CC11 channels through ${\cal O}(\alpha_{s})$ at the parton level. We find that
the associated uncertainties can be of order 100 MeV, thus competitive with
those possibly arising in the non-perturbative regime and indeed above the
current experimental estimates.


abstract:
  We investigate the B meson light-cone distribution amplitudes in the
heavy-quark limit which are relevant for the QCD factorization approach for the
exclusive B meson decays. We derive exact relations between two- and
three-particle distribution amplitudes from the QCD equations of motion and
heavy-quark symmetry constraint. As solution of these relations, we give
representations for the quark-antiquark distribution amplitudes in terms of
independent dynamical degrees of freedom. In particular, we find that the
Wandzura-Wilczek-type contributions are determined uniquely in analytic form in
terms of \bar{\Lambda}, a fundamental mass parameter of heavy-quark effective
theory, and that both leading- and higher-twist distribution amplitudes receive
the contributions of multi-particle states with additional gluons.


title: Selectron Pair Production in Electron-Electron-Scattering

abstract:
  We investigate pair production of selectrons in electron-electron-scattering
with subsequent decay into an electron and the LSP including ISR and
beamstrahlung. This process can be used at a linear collider to measure the
selectron masses and the gaugino mass parameter M_1 very precisely.


title:
The ionization of H, He and Ne atoms using neutrinos or antineutrinos at
  keV energies

abstract:
  We calculate the ionization cross sections for H, He or Ne atoms using
$\nu_e$ and $\bar \nu_e$ scattering at keV energies. Such cross sections are
useful for e.g. $\bar \nu_e$-oscillation experiments using a tritium source.
Using realistic atomic wave functions, we find that for $E_\nu \lsim 10 ~\rm
keV $ the atomic ionization cross sections, normalized to one electron per unit
volume, are smaller than the corresponding free electron ones, and that they
approach it from below as energies of 20 keV are reached.


title:
Remarks on the high-energy behaviour of cross-sections in weak-scale
  string theories

abstract:
  We consider the high-energy behaviour of processes involving Kaluza-Klein
(KK) gravitons of weak-scale string theories. We discuss how form-factors
derived within string theory modify the couplings of KK gravitons and thereby
lead to an exponential fall-off of cross sections in the high-energy limit.
Further, we point out that the assumption of Regge behaviour for a scattering
amplitude in the high energy limit, $T\propto s^{\alpha(t)}$, combined with a
linear growth of the total cross-section, $\sigma_{tot}(s)\propto s$, violates
elastic unitarity. Regge behaviour leads to a stringent bound on the growth of
the total cross-section, $\stot (s) \leq 32\pi \alpha' \ln(s/s_0)$.


title:
On the intrinsic charm and the recombination mechanisms in charm hadron
  production

abstract:
  We study $\Lambda_c^\pm$ production in $pN$ and $\pi^-N$ interactions. Recent
experimental data from the SELEX and E791 Collaborations at FNAL provide
important information on the production mechanism of charm hadrons. In
particular, the production of the $\Lambda_c$ baryon provides a good test of
the intrinsic charm and the recombination mechanisms, which have been proposed
to explain the so called leading particle effects.


title: Transverse Lambda polarization in semi-inclusive DIS

abstract:
  Following a previous description of Lambda and Lambda-bar polarization in
unpolarized p-p interactions, within a perturbative QCD factorization scheme
with new polarizing fragmentation functions, here we investigate the transverse
polarization of Lambda's and Lambda-bar's produced in semi-inclusive DIS.
Analytical expressions for both neutral and charged current exchange are given.
Since quantitative predictions cannot be given at this stage and comparison
with existing data are not yet significant, we present the general formalism
and a qualitative analysis displaying generic features of the Lambda and
Lambda-bar polarization for specific scenarios. Different kinematical
situations are considered, corresponding to experiments currently able to study
Lambda production in semi-inclusive DIS.


title: Aspects of Charmonium Physics

abstract:
  I review possible resolution of the $J/\psi (\psi^{\prime}) \to \rho-\pi$
puzzle based on two inputs: the relative phase between the one- photon and the
gluonic decay amplitudes, and a possible hadronic excess in the inclusive
nonelectromagnetic decay rate of $\psi^{\prime}$. The status of a universal
large phase here is examined for its meaning and implications (including those
for B-physics). Since the future of tau/charm facility(s) are again under
consideration together with a future anti-proton facility at GSI, I propose to
extend my review to include a broader discussion of charmonium physics.
Outstanding questions like the status of the $^{1}P_{1}$ state of charmonium,
measuring $D^{0}-\bar D^{0}$ mixing and relative strong phases, status of
molecular P(S) - wave charmonia will also be discussed amongst others.


title: $D^*D\pi$ form factor revisited

abstract:
  The $D^*D\pi$ form factor is evaluated in a QCD sum rule calculation for both
$D$ and $\pi$ off-shell mesons. We study the Borel sum rule for the three-point
function of one pseudoscalar, one axial and one vector meson currents. We find
that the momentum dependence of the form factors is very different if the $D$
or the $\pi$ meson is off-shell, but they lead to the same coupling constant in
the $D^*D\pi$ vertex.


title: Partons and QCD in high-energy polarized pp collisions

abstract:
  We present and use a technique for implementing in a fast way, and without
any approximations, higher-order calculations of partonic cross sections into
global analyses of parton distribution functions. The approach, which is set up
in Mellin-moment space, is particularly suited for analyses of future data from
polarized proton-proton collisions at RHIC, but not limited to this case. We
also briefly discuss the effects of soft-gluon resummations on spin
asymmetries.


title:
Heavy-Meson Observables at One-Loop in Partially Quenched Chiral
  Perturbation Theory

abstract:
  I present one-loop level calculations of the Isgur-Wise functions for B ->
D^{(*)} + e + nu, of the matrix elements of isovector twist-2 operators in B
and D mesons, and the matrix elements for the radiative decays D^* -> D + gamma
in partially quenched heavy quark chiral perturbation theory. Such expressions
are required in order to extrapolate from the light quark masses used in
lattice simulations of the foreseeable future to those of nature.


title: Chiral Symmetry and Scalars

abstract:
  The suggestion by Jaffe that if $\sigma$ is a light $q^{2}\bar{q}^{2}$ state
$0^{++}$ then even the fundamental chiral transformation properties of the
$\sigma$ becomes {\bf unclear}, has stimulated much interest. Adler pointed out
that in fact the seminal work on chiral symmetry via PCAC consistency, is
really quite consistent with the $\sigma$ being predominantly
$q^{2}\bar{q}^{2}$. This interpretation was actually backed by subsequent work
on effective Lagrangian methods for linear and non linear realizations. More
recent work of Achasov suggests that intermediate four-quark states determine
amplitudes involving other scalars $a_{0}(980)$ and $f_{0}(980)$ below 1 GeV,
and the report by Ning Wu that study on $\sigma$ meson in $J/\psi \to
\omega\pi^{+}\pi^{-}$ continue to support a non $q\bar{q}$ $\sigma$ with mass
as low as 390 MeV. It is also noted that more recent re-analysis of $\pi K$
scattering by S. Ishida {\em et al.} together with the work of the E791
Collaboration, support the existence of the scalar $\kappa$ particle with
comparatively light mass as well.


title: Skyrme Model Language in the Theory of Nucleons and Nuclei

abstract:
  In this talk we try to clarify the problems existing on the way of theorist
decided to construct nuclear theory on the generalized Skyrme model background.
We conclude that to construct such a model of light nuclei one have to
construct a hybrid model where one particle degrees of freedom are concentrated
around the surface of the nuclei and soliton with non-trivial structure is
located at the center region.


title: Phenomenological Estimation of Parameters in minimal Supergravity Model

abstract:
  Several parameters of the minimal supergravity model are estimated by the
method of the renormalization group. In this model, five arbitrary parameters
$(m_0, m_{1/2}, \tan{\beta}, A_0, {sig}(\mu))$ are contained. $\tan{\beta}$ is
evaluated as 7.5 by the likelihood analysis of the gauge and Yukawa coupling
constants. Further, the trilinear coupling constant $A_0$ is fixed by the
equation of $B_0=(A_0-1)m_0$ at the GUT scale $M_X \simeq 2\times10^{16}$(GeV)
and by the Higgs potential at the Z-boson mass scale $M_Z=$91(GeV). As the
results, (1) allowed $m_0-m_{1/2}$ regions, (2) the sparticle mass spectra, and
(3) the lightest supersymmetric particle mass are shown in this paper.


title: New Physics at Polarized Hadronic Colliders

abstract:
  Concerning new physics beyond the Standard Model we explore the discovery and
analysis potentials of polarized (hadronic) experiments and we compare with the
unpolarized case. For discovery, beam polarization is helpful in the case of
purely hadronic new interactions. In any case, beam polarization provides us a
unique piece of information on the chiral and flavour structures.


title:
GaGaRes: A Monte Carlo generator for resonance production in two-photon
  physics

abstract:
  In this paper a Monte Carlo generator, GaGaRes, is presented which can be
used to describe two-photon resonance production in e^+e^- collisions. The
program can generate the five lowest-lying C=+1 meson states of any q\bar{q}
combination together with the outgoing electron and positron. The dependence on
the photon virtualities Q_1^2 and Q_2^2 is fully taken into account. The
program also generates the density matrices of the resonance, which form an
essential tool in the description of the decay of the resonances. Furthermore,
the program is applicable for all tagging conditions.


title:
How to explicitly introduce the Jaffe-Witten mass gap into the quantum
  Yang-Mills theory

abstract:
  We propose how to explicitly introduce the Jaffe-Witten mass gap into the
quantum Yang-Mills theory. Through the full gluon propagator it is defined as
such nonperturbative scale that when it formally goes to zero, then the
perturbative phase survives in the theory only. The close link between mass gap
and strong infrared singularities which are due to dominated in the QCD vacuum
self-interaction of massless gluons is also discussed. This interaction leads
thus to the zero momentum modes enhancement effect in the QCD nonperturbative
vacuum. Using theory of distributions, we argue that strong nonperturbative
infrared singularities can be put under control. A new, intrinsically
nonperturbative phase in QCD is established.


title: Flavour Physics and CP Violation in the SM

abstract:
  We review the main aspects of Flavour Physics and CP Violation in the
Standard Model. After presenting a grand view of the field including a Master
Formula for weak decays we discuss i) Standard analysis of the unitarity
triangle, ii) The ratio epsilon'/epsilon, iii) Rare decays K^+ -> pi^+ nu barnu
and K_L -> pi^0 nu barnu, iv) CP violation in B decays and v) Models with
Minimal Flavour Violation. Our review ends with 20 questions that hopefully
will be answered in the coming years.


title: The role of jet quenching in the p-bar >= pi- anomaly at RHIC

abstract:
  Preliminary PHENIX data on $Au+Au$ reactions at $\sqrt{s}= 130$ AGeV suggest
that $\bar{p}$ yields may exceed $\pi^-$ at high $p_{\rm T} > 2$ GeV/c. We
propose that jet quenching in central collisions suppresses the hard PQCD
component of the spectra in central $A+A$ reactions, thereby exposing a novel
non-perturbative component of baryon dynamics. We suggest that baryon junctions
provide a possible explanation of the anomalous component. We predict that the
$\bar{p} \geq \pi^-$ anomaly is limited to a finite $p_{\rm T}$ window and
decreases with increasing impact parameter.


title:
A Preliminary Look at the Physics Reach of a Solar Neutrino TPC:
  Time-Independent Two Neutrino Oscillations

abstract:
  This paper will discuss the physics reach of a solar neutrino TPC containing
many tons of He4 under high pressure. Particular attention is given to the LMA
and SMA solutions, which are allowed by current data, and which are
characterized by a lack of time-dependent phenomena (either summer-winter or
day-night asymmetries). In this case, the physics of neutrino masses and mixing
is all contained in the energy dependence of the electron neutrino survival
probability, (or in its reciprocal, the electron neutrino disappearance
probability).


title:
Implications of the SNO and the Homestake Results for the BOREXINO
  Experiment

abstract:
  Using the recent result of the SNO solar neutrino experiment, we have
demonstrated in a model independent way that the contribution of Be-7 and other
medium energy neutrinos to the event rate of the Homestake experiment is 4
sigma smaller than the BP2000 SSM prediction. We have considered the
implications of this result for the future BOREXINO experiment.


title: A gluonic mechanism for B --> D eta'

abstract:
  We present a calculation of the process B --> D eta' within a heavy-light
chiral quark model. We assume that the eta' has a large gluonic component, and
its coupling is described via the glue-glue-eta' effective vertex. The main
contribution comes from the non-factorizable part of the effective weak
Lagrangian at quark level. We find, within our model-dependent assumptions, a
branching ratio Br(B --> D eta') = (1.7 -- 3.3) 10^(-4), somewhat below the
experimental upper bound 9.4 10^(-4).


title: Ultrahigh Energy Neutrinos and Cosmic Rays as Probes of New Physics

abstract:
  Cosmic high energy neutrinos are inextricably linked to the origin of cosmic
rays which is one of the major unresolved questions in astrophysics. In
particular, the highest energy cosmic rays observed possess macroscopic
energies and their origin is likely to be associated with the most energetic
processes in the Universe. Their existence triggered a flurry of theoretical
explanations ranging from conventional shock acceleration to particle physics
beyond the Standard Model and processes taking place at the earliest moments of
our Universe. Furthermore, many new experimental activities promise a
considerable increase of statistics at the highest energies and a combination
with gamma-ray and neutrino astrophysics will put strong constraints on these
theoretical models. The detection of ultra high energy neutrinos in particular
is made likely by new experimental techniques and will open an important new
channel. We give an overview over this quickly evolving field with special
emphasize on new experimental ideas and possibilities for probing new physics
beyond the electroweak scale.


title:
Model independent constraints on contact interactions from polarized
  Bhabha scattering at LC

abstract:
  We discuss electron-electron contact-interaction searches in the process
e^+e^- -->e^+e^- at a future e^+e^- Linear Collider with c.m. energy
\sqrt{s}=0.5 TeV and with both beams longitudinally polarized. Our analysis is
based on the measurement of the polarized differential cross sections, and
allows to simultaneously take into account the general set of contact
interaction couplings as independent, non-zero, parameters thus avoiding
simplifying, model-dependent, assumptions. We evaluate the corresponding
model-independent constraints on the coupling constants, emphasizing the role
of beam polarization, and make a comparison with the case of e^+e^-
-->\mu^+\mu^-.


title: Are There Pressure Waves in the Vacuum?

abstract:
  The Higgs vacuum is a kind of medium. In any medium one generally expects
sound waves for sufficiently long wavelengths (>> mean free path). I briefly
describe how the broken-symmetry vacuum can be viewed as a Bose-Einstein
condensate of `phion' particles. This picture yields a natural notion of the
`mean free path'. I speculate that this is at the millimeter-centimeter scale.


title: Diffraction Dissociation in QCD and Light-Cone Wavefunctions

abstract:
  The diffractive dissociation of a hadron at high energies, by either Coulomb
or Pomeron exchange, has a natural description in QCD as the materialization of
the projectile's light-cone wavefunctions; in particular, the diffractive
dissociation of a meson, baryon, or photon into high transverse momentum jets
measures the shape and other features of the projectile's distribution
amplitude. Diffractive dissociation can thus test fundamental properties of
QCD, including color transparency and intrinsic charm. All of these effects
have an impact on exclusive decays of $B$ mesons and the study of $CP$
violation. I also discuss recent work which shows that the structure functions
measured in deep inelastic lepton scattering are affected by final-state
rescattering, thus modifying their connection to light-cone probability
distributions. In particular, the shadowing of nuclear structure functions is
due to destructive interference effects from leading-twist diffraction of the
virtual photon, physics not included in the nuclear light-cone wavefunctions.


title: Problems with lattice methods for electroweak preheating

abstract:
  Recently Garcia Bellido et. al. have proposed that electroweak baryogenesis
may occur at the end of inflation, in a scenario where the reheat temperature
is too low for electroweak symmetry restoration. I show why the scenario is
difficult to test reliably by classical field techniques on the lattice.


title: Brane Gas Inflation

abstract:
  We consider the brane gas picture of the early universe. At later stages,
when there are no winding modes and the background is free to expand, we show
that a moving 3-brane, which we identify with our universe, can inflate even
though it is radiation-dominated. The crucial ingredients for successful
inflation are the coupling to the dilaton and the equation of state of the
bulk. If we suppose the brane initially forms in a collision of
higher-dimensional branes, then the spectrum of primordial density fluctuations
naturally has a thermal origin.


title:
Contribution of $\alpha^2$-terms to the total interaction cross sections
  of relativistic elementary atoms with atoms of matter

abstract:
  It is shown that the corrections of $\alpha^2$ order to the total cross
sections for interaction of elementary hydrogen-like atoms with target atoms,
reported in the previously published paper [S.Mrowczynski, Phys.Rev. D36, 1520
(1987)], do not include some terms of the same order of magnitude. That results
in a significant contribution of these corrections in particular cases. The
full $\alpha^2$-corrections have been derived and it is shown that they are
really small and could be omitted for most practical applications.


title:
Rest masses of elementary particles as effective masses at zero
  temperature

abstract:
  We introduce a new approach to generate dinamically the masses of elementary
particles in the $SU(3)_C \times SU(2)_L \times U(1)_Y$ Standard Model without
Higgs Sector (SMWHS). We start from the assumption that rest masses correspond
to the effective masses of particles in an elementary quantum fluid at zero
temperature. These effective masses are obtained through radiative corrections,
at one-loop order, in the context of the real time formalism of quantum field
theory at finite temperature and density. The quantum fluid is described in
structure and dynamics by the SMWHS and it is characterized by non-vanishing
chemical potentials associated to the different fermion flavour species.
Starting from the experimental mass values for quarks and leptons, taking the
top quark mass as $m_t = 172.916$ GeV, we can compute, as an evidence of the
consistency of our approach, the experimental central mass values for the
$W^{\pm}$ and $Z^0$ gauge bosons. Subsequently we introduce in the SMWHS a
massless scalar field leading to Yukawa coupling terms in the Lagrangian
density. For this case we can also compute the experimental mass central values
of the $W^{\pm}$ and $Z^0$ gauge bosons using a top quark mass value in the
range 169.2 GeV $< m_{t} < 178.6$ GeV; this range for the top quark mass
implies that the scalar boson mass must be in the range $0 < M_{H} < 152$ GeV.


title: Strong nuclear enhancement in intermediate mass Drell-Yan production

abstract:
  We calculate nuclear effect in Drell-Yan massive lepton-pair production in
terms of parton multiple scattering in Quantum Chromodynamics (QCD). We present
the nuclear modification to inclusive Drell-Yan cross section $d\sigma/dQ^2$ in
terms of multiparton correlation functions. By extracting the size of the
correlation functions from measured Drell-Yan transverse momentum broadening in
nuclear medium, we determine the nuclear modification at $O(\alpha_s/Q^2)$. We
find that the nuclear modification strongly enhances the inclusive Drell-Yan
cross section in the intermediate mass region (IMR): $1.5 < Q < 2.5$ GeV. We
argue that the Drell-Yan process is responsible for the majority of the
observed dimuon enhancement in the IMR in the Pb-Pb collisions at CERN SPS.


title:
$\Theta$ vacua states in heavy ion collisions in presence of dissipation
  and noise

abstract:
  We have studied possible formation of $\Theta$ vacua states in heavy ion
collisions. Random phases of the chiral fields were evolved in a finite
temperature potential, incorporating the breaking of $U_A(1)$ symmetry. Initial
random phases very quickly settle into oscillation around the values dictated
by the potential. The simulation study indicate that an initial $\Theta$=0
state do not evolve into a $\Theta$ $\neq$ 0 state. However, an initial
$\Theta$ $\neq$ 0 state, if formed in heavy ion collision, can survive, as a
coherent superposition of a number of modes.


title:
Fermion universality manifesting itself in the Dirac component of
  neutrino mass matrix

abstract:
  An effective texture is presented for six Majorana conventional neutrinos
(three active and three sterile), based on a 6x6 neutrino mixing matrix whose
3x3 active-active component arises from the popular bimaximal mixing matrix of
active neutrinos $\nu_e$, $\nu_\mu$, $\nu_\tau$ by three small rotations in the
14, 25, 36 planes of $\nu_1$, $\nu_2$, $\nu_3$ and $\nu_4$, $\nu_5$, $\nu_6$
neutrino mass states. The Dirac component (i.e. 3x3 active-sterile component)
of the resulting 6x6 neutrino mass matrix is conjectured to get a structure
similar to the charged lepton and quark 3x3 mass matrices, after the bimaximal
mixing, specific for neutrinos, is transformed out unitarily {}from the
neutrino mass matrix. The charged lepton and quark mass matrices are taken in a
universal form constructed previously by the author with a considerable
phenomenological success. Then, for the option of $m^2_1\simeq m^2_2\simeq
m^2_3\gg m^2_4\simeq m^2_5\simeq m^2_6\simeq0$, the proposed texture {\it
predicts} oscillations of solar $\nu_e$'s with $\Delta m^2_{\rm
sol}\equiv\Delta m^2_{21}\sim(1.1$ to 1.2)$\times10^{-5}$ eV$^2$, not
inconsistent with the LMA solar solution, if the SuperKamiokande value $\Delta
m^2_{\rm atm}\equiv\Delta m^2_{32}\sim$(3 to 3.5)$\times10^{-3}$ eV$^2$ for
oscillations of atmospheric $\nu_\mu$'s is taken as an input.


title:
Electromagnetic couplings of the ChPT Lagrangian from the perturbative
  chiral quark model

abstract:
  We apply the perturbative chiral quark model to the study of the low-energy
pi-N interaction. Using an effective chiral Lagrangian we reproduce the
Weinberg-Tomozawa result for the S-wave pi-N scattering lengths. After
inclusion of the photon field we give predictions for the electromagnetic
O(p^2) low-energy couplings of the chiral perturbation theory effective
Lagrangian that define the electromagnetic mass shifts of nucleons and
first-order (e^2) radiative corrections to the pi-N scattering amplitude.
Finally, we estimate the leading isospin-breaking correction to the strong
energy shift of the pi(-)p atom in the 1s state, which is relevant for the
experiment "Pionic Hydrogen" at PSI.


title: Adiabatic CMB perturbations in pre-big bang string cosmology

abstract:
  We consider the pre-big bang scenario with a massive axion field which starts
to dominate energy density when oscillating in an instanton-induced potential
and subsequently reheats the universe as it decays into photons, thus creating
adiabatic CMB perturbations. We find that the fluctuations in the axion field
can give rise to a nearly flat spectrum of adiabatic perturbations with a
spectral tilt $\Delta n$ in the range $-0.1 \lesssim \Delta n \lesssim 1$.


title: Newtonian gravity from the Higgs field: the sublimation of aether

abstract:
  We illustrate why a space-time structure as in General Relativity is not in
contradiction with a dynamical origin of gravity from a scalar field. Further,
we argue that the recently discovered gap-less mode of the singlet Higgs field
represents the most natural dynamical agent of Newtonian gravity.


title: Nonleptonic $\Omega^{-}$ decays and the Skyrme model

abstract:
  Nonleptonic $\Omega^{-}$ decay branching ratios are estimated by means of the
QCD enhanced effective weak Hamiltonian supplemented by the SU(3) Skyrme model
used to estimate the nonperturbative matrix elements. The model has only one
free parameter, namely the Skyrme charge $e$, which is fixed through the
experimental values of the octet-decuplet mass splitting $\Delta $ and the
axial coupling constant $g_{A}$. The whole scheme is equivalent to that which
works well for the nonleptonic hyperon decays. The ratios of calculated
amplitudes are in agreement with experiment. However, the absolute values are
about twice too large if short-distance corrections and only ground
intermediate states are included.


title: Physics with Low-Energy Muons at a Neutrino Factory Complex

abstract:
  The physics potential of an intense source of low-energy muons is studied.
Such a source is a necessary stage towards building the neutrino factories and
muon colliders which are being considered at present. The CERN Neutrino Factory
could deliver muon beams with intensities 3-4 orders of magnitude higher than
available now, with large freedom in the choice of the time structure.
Low-energy muon physics contributes to many fields of basic research, including
rare muon decays, i.e., decays that do not conserve muon number, measurements
of fundamental constants, the muon anomalous magnetic moment, determination of
the Lorentz structure of the weak interaction, QED tests, CPT tests, proton and
nuclear charge distributions (even for short-lived isotopes), and condensed
matter physics. In studying the experimental programme, we analyse the present
limitations, list the requirements on the new muon beams, and describe some
ideas on how to implement these beam lines in a CERN neutrino factory complex.


title: Cosmic microwave background and parametric resonance in reheating

abstract:
  The variation of the perturbative 3-curvature parameter, \zeta, is
investigated in the period of reheating after inflation. The two-field model
used has the inflaton, with an extra scalar field coupled to it, and non-linear
effects of both fields are included as well as a slow decay mechanism into the
hydrodynamic fluid of the radiation era. Changes in \zeta occur and persist
into the succeeding cosmic eras to influence the generation of the cosmic
microwave background fluctuations.


title: Highlights of Short Baseline Physics at a Neutrino Factory

abstract:
  We review the physics potential for experiments with intense neutrino beams
at the front-end of a muon storage ring, stressing the way the spin and flavour
structure of neutrino interactions with matter can be used to shed light on the
structure of the strong and electroweak interactions. Specifically, we discuss
precision tests of the standard model, studies of polarized and unpolarized
structure functions of the nucleon, and several new and exotic physics items.


title: Power Corrections in QCD

abstract:
  This article provides a review of progress made in understanding inverse
power law corrections 1/Q^p where Q is the hard scale for a given QCD
observable. Special emphasis is given to comparisons of theory with HERA
results.


abstract:
  Theoretical aspects of transversity observables are reviewed. The main focus
is on two leading twist transversity single spin asymmetries, one arising from
the Collins effect and one from the interference fragmentation functions.
Electron-positron annihilation experiments which are required to obtain these
fragmentation functions are discussed, as well as the issues of factorization,
evolution and Sudakov factors for the relevant observables. These theoretical
considerations pinpoint the most realistic scenarios towards measurements of
transversity.


title: Charged Current Universality in the MSSM

abstract:
  We compute the complete one-loop contributions to low-energy charged current
weak interaction observables in the Minimal Supersymmetric Standard Model
(MSSM). We obtain the constraints on the MSSM parameter space which arise when
precision low-energy charged current data are analyzed in tandem with
measurements of the muon anomaly. While the data allow the presence of at least
one light neutralino, they also imply a pattern of mass splittings among first
and second generation sleptons and squarks which contradict predictions of
widely used models for supersymmetry breaking mediation.


title:
Freezing of the QCD coupling constant and solutions of Schwinger-Dyson
  equations

abstract:
  We compare phenomenological values of the frozen QCD running coupling
constant ($\alpha_s$) with two classes of solutions obtained through
nonperturbative Schwinger-Dyson equations. We use these same solutions with
frozen coupling constants as well as their respective nonperturbative gluon
propagators to compute the QCD prediction for the asymptotic pion form factor.
Agreement between theory and experiment on $\alpha_s(0)$ and $F_\pi (Q^2)$ is
found only for one of the solutions Schwinger-Dyson equations.


title: g-2 From Noncommutative Geometry

abstract:
  This brief Letter demonstrates that effects from a $\nc$ space-time geometry
will measurably affect the value of $(g-2)_\mu$ inferred from the decay of the
muon to an electron plus two neutrinos. If the scale of noncommutivity is
${\cal O}(TeV)$, the alteration of the $V-A$ structure of the lepton-lepton-W
vertex is sufficient to shift the inferred value of $(g-2)_\mu$ to one part in
$10^8$. This may account for the recently reported $2.6 \sigma$ discrepancy
between the BNL measurement $a_{expt} = 11659202(14)(6) \times 10^{-10}$ and
the Standard Model prediction $a_{SM} = 11659159.6(6.7) \times 10^{-10}$.


title: Can cosmic rays provide sign of strangelets?

abstract:
  We discuss the possible imprints of Strange Quark Matter (SQM) in cosmic ray
data. In particular, we investigate the propagation of SQM through the
atmosphere and discuss: i) direct candidates for strangelets, ii) exotic events
interpreted as signals of SQM and iii) muon bundles and delayed neutrons in
Extensive Air Showers. The physics and astrophysics of SQM is shortly reviewed.
We point out the possibility that extreme energy cosmic rays are the results of
the decay of unstable primordial objects. Finally, the abundance of possible
candidates for strangelets and their mass spectrum are estimated and compared
with the astrophysical limits and prospects of the possible observation of SQM
in accelerator experiments are outlined.


title:
Mass matrices and eigenstates for scalars / pseudoscalars; indirect CP
  violation, mass hierarchies and symmetry breaking

abstract:
  I study indirect CP violation for neutral kaons, and extend it to large
values of the CP-violating parameter (taken to be real). I show how and at
which condition there can exist a continuous set of basis in which the kinetic
and mass terms in the Lagrangian can be diagonalized simultaneously. An
ambiguity results for the mass spectrum, which then depends on the basis. In
particular, for fixed (positive) (mass)^2 of the CP eigenstates K^0_1, K^0_2,
and for certain ranges of values of the CP-violating parameter, a negative
(mass)^2 can arise in the CP-violating basis. Under certain conditions, even a
small perturbation, by lifting the ambiguity, can strongly alter the pattern of
masses. These investigations extend in a natural way to indirect CP violation
among a set of Higgs-like doublets. The C-odd commutator [K^0, K^0 bar], or its
equivalent for Higgs multiplets, plays an important role. The condition for its
vanishing and its consequences are among the main concerns of this work.


title: Rates of neutrino conversion and decay in hot and dense QED plasma

abstract:
  Using a real-time formalism of equilibrium and nonequilibrium quantum-field
theory, we derive the reaction-rate formula for neutrino-conversion ($\nu \to
\nu'$) process and $\nu \bar{\nu}'$ annihilation process, which take place in a
hot and dense QED plasma with background (anti)neutrinos out of equilibrium.
Also derived is the formula for the inverse processes to the above ones. Using
the hard-thermal-loop resummation scheme, we include the contribution from the
coherent processes. The decay/production of a neutrino causes an evolution of
its spatial distribution. A scheme for dealing with this evolution is
presented. For the case of isotropic neutrino distribution, numerical
computation is carried out for the parameter region of type-II super-nova
explosion. Defferential reaction rate exhibits characteristic peak structure,
which comes from the coherent processes. The contribution from the above
processes to the decay or damping rate of a parent neutrino $\nu$ is also
studied.


title:
Width and Partial Widths of Unstable Particles in the Light of the
  Nielsen Identities

abstract:
  Fundamental properties of unstable particles, including mass, width, and
partial widths, are examined on the basis of the Nielsen identities (NI) that
describe the gauge dependence of Green functions. In particular, we prove that
the pole residues and associated definitions of branching ratios and partial
widths are gauge independent to all orders. A simpler, previously discussed
definition of branching ratios and partial widths is found to be gauge
independent through next-to-next-to-leading order. It is then explained how it
may be modified in order to extend the gauge independence to all orders. We
also show that the physical scattering amplitude is the most general
combination of self-energy, vertex, and box contributions that is gauge
independent for arbitrary s, discuss the analytical properties of the NI
functions, and exhibit explicitly their one-loop expressions in the Z-gamma
sector of the Standard Model.


title: Multiskyrmions and baryonic bags

abstract:
  Analytical treatment of skyrmions given by rational map (RM) ansaetze
proposed recently for the Skyrme model is extended to the model including the
6-th order term in chiral fields derivatives in the lagrangian (the SK6 variant
of the model) and used for calculation of different properties of
multiskyrmions. For special class of profile functions approximating the true
profile and the domain wall behaviour at the same time, the masses and other
static properties of multiskyrmions are expressed in terms of the Euler-type
integrals. An upper bound is obtained for the masses of RM multiskyrmions which
is close to the calculated masses, especially at large B. The gap between
rigorous upper bound and lower bound, obtained for the SK6 model as well, for
large B multiskyrmions is less than 9%, in comparison with about 4% for the SK4
(Skyrme) variant. The basic properties of such bubbles of matter are
investigated, some of them, e.g. the thickness of the bubbles envelope, being
of universal character, i.e. they do not depend on baryon number of
configuration, or reveal a simple and natural dependence. The dependence of
these properties on the number of flavours is absent or very weak in both
models. Qualitatively, the properties of the baryonic bags are the same for the
SK6 and SK4 variants of the model, although differ in some details.


title:
Particle production from symmetry breaking after inflation and
  leptogenesis

abstract:
  Recent studies suggest that the process of symmetry breaking after inflation
typically occurs very fast, within a single oscillation of the
symmetry-breaking field, due to the spinodal growth of its long-wave modes,
otherwise known as `tachyonic preheating'. We show how this sudden transition
from the false to the true vacuum can induce a significant production of
particles, bosons and fermions, coupled to the symmetry-breaking field. We find
that this new mechanism of particle production in the early Universe may have
interesting consequences for the origin of supermassive dark matter and the
generation of the observed baryon asymmetry through leptogenesis.


title: QCD Matrix Elements + Parton Showers

abstract:
  We propose a method for combining QCD matrix elements and parton showers in
Monte Carlo simulations of hadronic final states in $e^+e^-$ annihilation. The
matrix element and parton shower domains are separated at some value $y_{ini}$
of the jet resolution, defined according to the $k_T$-clustering algorithm. The
matrix elements are modified by Sudakov form factors and the parton showers are
subjected to a veto procedure to cancel dependence on $y_{ini}$ to
next-to-leading logarithmic accuracy. The method provides a leading-order
description of hard multi-jet configurations together with jet fragmentation,
while avoiding the most serious problems of double counting. We present first
results of an approximate implementation using the event generator APACIC++.


title:
The Radiative rare decays $B\to K^{**}\gamma$ in the light-cone QCD sum
  rule approach

abstract:
  We predict contributions of higher $K$-resonances to the radiative rare
decays $b\to s\gamma$, in the framework of the QCD sum rules on the light cone,
which combines the traditional QCD sum rule method with the description of
final state mesons in terms of the light-cone wave functions of increasing
twist. Our calculations are restricted to the leading twist-two operators for
$K^*(892)$ and to the asymptotic wave function for the other $K^{**}$-mesons.
  Using experimental data on the semileptonic $\tau\to K^{**}\nu_{\tau}$
decays, we extract the corresponding decay constants for vector and
axial-vector $K^{**}$-mesons. Based on our estimate of the transition form
factor $F_1^{K^*(892)}(0)=0.32 \pm 0.06$ and the $K_2^*(1430)$ decay constant
$f_{K_2^*(1430)}=(160\pm 20) MeV$, we find good agreement with experimental
results. The two largest fractions of the inclusive $b\to s\gamma$ branching
ratio are found to be $(10.0\pm 4.0)%$ for $B\to K^*(892) \gamma$ and $(5.0\pm
2.0)%$ for $B\to K_2^*(1430)\gamma$ decays. We also compare our results with
the existing theoretical predictions.


title: High-p_T pion and kaon production in relativistic nuclear collisions

abstract:
  High-p_T pion and kaon production is studied in relativistic proton-proton,
proton-nucleus, and nucleus-nucleus collisions in a wide energy range. Cross
sections are calculated based on perturbative QCD, augmented by a
phenomenological transverse momentum distribution of partons (``intrinsic
k_T''). An energy dependent width of the transverse momentum distribution is
extracted from pion and charged hadron production data in
proton-proton/proton-antiproton collisions. Effects of multiscattering and
shadowing in the strongly interacting medium are taken into account.
Enhancement of the transverse momentum width is introduced and parameterized to
explain the Cronin effect. In collisions between heavy nuclei, the model
over-predicts central pion production cross sections (more significantly at
higher energies), hinting at the presence of jet quenching. Predictions are
made for proton-nucleus and nucleus-nucleus collisions at RHIC energies.


title: Pseudoscalar Mesons in Asymmetric Matter

abstract:
  The behavior of kaons and pions in hot non strange quark matter, simulating
neutron matter, is investigated within the SU(3) Nambu-Jona-Lasinio [NJL] and
in the Enlarged Nambu-Jona-Lasinio [ENJL] (including vector pseudo-vector
interaction) models. At zero temperature, it is found that in the NJL model,
where the phase transition is first order, low energy modes with K-, Pi+
quantum numbers, which are particle-hole excitations of the Fermi sea, appear.
Such modes are not found in the ENJL model and in NJL at finite temperatures.
The increasing temperature has also the effect of reducing the splitting
between the charge multiplets.


title: Theoretical Aspects of HERA Physics

abstract:
  We discuss the theoretical underpinnings for the extraordinary success of
perturbative QCD in the description of HERA data. In particular, we examine
recent progress in the understanding of perturbative QCD at small x. We explain
the relation between evolution equations in Q^2 and x, and how they can be used
for simultaneous resummation of the relevant large logs at HERA. We show that
while the HERA data can be understood within our current knowledge of the
perturbative expansion of QCD, they pose stringent constraints on the
perturbatively inaccessible behaviour of QCD in the Regge limit.


title: Double Threefold Degeneracies for Active and Sterile Neutrinos

abstract:
  We explore the possibility that the 3 active (doublet) neutrinos have nearly
degenerate masses which are split only by the usual seesaw mechanism from 3
sterile (singlet) neutrinos in the presence of a softly broken $A_4$ symmetry.
We take the unconventional view that the sterile neutrinos may be light, i.e.
less than 1 keV, and discuss some very interesting and novel phenomenology,
including a connection between the LSND neutrino data and solar neutrino
oscillations.


title:
Feynman-diagram evaluation in the electroweak theory with computer
  algebra

abstract:
  The evaluation of quantum corrections in the theory of the electroweak and
strong interactions via higher-order Feynman diagrams requires complicated and
laborious calculations, which however can be structured in a strictly
algorithmic way. These calculations are ideally suited for the application of
computer algebra systems, and computer algebra has proven to be a very valuable
tool in this field already over several decades. It is sketched how computer
algebra is presently applied in evaluating the predictions of the electroweak
theory with high precision, and some recent results obtained in this way are
summarized.


title:
Implications of CP Asymmetry Limits for $B \to K \pi$ and $B \to \pi
  \pi$

abstract:
  Recent experimental limits for the direct CP asymmetries in $B^0 \to K^+
\pi^-$, $B^+ \to K^+ \pi^0$, $B^+ \to K^0 \pi^+$, and $B^0 \to \pi^+ \pi^-$,
and for the indirect CP asymmetry in $B^0 \to \pi^+ \pi^-$, are combined with
information on CP-averaged branching ratios to shed light on weak and strong
phases. At present such bounds favor $\gamma \ge 60^\circ$ at the $1 \sigma$
level. The prospects for further improvements are discussed.


title:
Role of Present and Future Atomic Parity Violation Experiments in
  Precision Electroweak Tests

abstract:
  Recent reanalyses of the atomic physics effects on the weak charge in cesium
have led to a value in much closer agreement with predictions of the Standard
Model. We review precision electroweak tests, their implications for upper
bounds on the mass of the Higgs boson, possible ways in which these bounds may
be circumvented, and the requirements placed upon accuracy of future atomic
parity violation experiments by these considerations.


title: CP Symmetry Violation

abstract:
  An elementary description of CP violation for the non-specialist is
presented. This article, for publication in {\it Macmillan Encylopedia of
Physics, Supplement: Elementary Particle Physics}, is being submitted to the
Archive for comments by colleagues.


title: The Eightfold Way

abstract:
  An elementary description of the Eightfold Way for the non-specialist is
presented. This article, for publication in {\it Macmillan Encylopedia of
Physics, Supplement: Elementary Particle Physics}, is being submitted to the
Archive for comments by colleagues.


title: Experimental Signature for Black Hole Production in Neutrino Air Showers

abstract:
  The existence of extra degrees of freedom beyond the electroweak scale may
allow the formation of black holes in nearly horizontal neutrino air showers.
In this paper we examine the average properties of the light descendants of
these black holes. Our analysis indicates that black hole decay gives rise to
deeply penetrating showers with an electromagnetic component which differs
substantially from that in conventional neutrino interactions, allowing a good
characterization of the phenomenon against background. Naturally occurring
black holes in horizontal neutrino showers could be detected and studied with
the Auger air shower array. Since the expected black hole production rate at
Auger is $> 1$ event/year, this cosmic ray observatory could be potentially
powerful in probing models with extra dimensions and TeV-scale gravity.


title: B Physics Overview: Rare Hadronic and Radiative Decays

abstract:
  I discuss three B physics results with potential for exhibiting new
flavour-changing interactions: (1) the time-dependent CP asymmetry in B\to
J/\psi K_S decay; (2) branching fractions and CP asymmetries in B\to \pi\pi,
\pi K decays; (3) inclusive and exclusive semi-hadronic b\to s transitions.


title: $\bar B\to D\tau \bar\nu_{\tau}$ in two-Higgs-doublet model

abstract:
  We study the exclusive semi-tauonic B decay, $\bar B \to D \tau
\bar\nu_{\tau}$, in two-Higgs-doublet models. Using recent experimental and
theoretical results on hadronic form factors, we estimate theoretical
uncertainties in the branching ratio. As a result, we clarify the potential
sensitivity of this mode to the charged Higgs exchange. Our analysis will help
to probe the charged Higgs boson at present and future B factory experiments.


title: Nonunitary neutrino mixing matrix and CP violating neutrino oscillations

abstract:
  In the standard approach to the neutrino oscillations a unitary relation
among weak and mass eigenstates of light neutrinos is imposed. However, in many
extensions of the SM left-handed, active neutrinos mix with additional heavy
neutrino states. Consequences of this additional mixing, driven by experimental
constraints, on the neutrino oscillations are considered.


title:
Comparison of Phase Space Slicing and Dipole Subtraction Methods for
  gamma^* -> Q Qbar

abstract:
  We compare the phase space slicing and dipole subtraction methods in the
computation of the inclusive and differential next-to-leading order cross
sections for heavy quark production in the simple process gamma^* -> Q Qbar.
For the phase space slicing method we study the effects of improvement terms
that remove restrictions on the slicing parameter s_min. For the dipole method
our comparison is a first check on some of its counterterms involving massive
quarks, derived recently. In our comparison we address issues such as numerical
accuracy and efficiency.


title: Cosmic Rays and Large Extra Dimensions

abstract:
  We have proposed that the cosmic ray spectrum "knee", the steepening of the
cosmic ray spectrum at energy $E \gsim 10^{15.5}$ eV, is due to "new physics",
namely new interactions at TeV cm energies which produce particles undetected
by the experimental apparatus. In this letter we examine specifically the
possibility that this interaction is low scale gravity. We consider that the
graviton propagates, besides the usual four dimensions, into an additional
$\delta$, compactified, large dimensions and we estimate the graviton
production in $p p$ collisions in the high energy approximation where graviton
emission is factorized. We find that the cross section for graviton production
rises as fast as $(\sqrt{s}/M_f)^{2+\delta}$, where $M_f$ is the fundamental
scale of gravity in $4+\delta$ dimensions, and that the distribution of
radiating a fraction $y$ of the initial particle's energy into gravitational
energy (which goes undetected) behaves as $\delta y^{\delta -1}$. The missing
energy leads to an underestimate of the true energy and generates a break in
the {\sl inferred} cosmic ray spectrum (the "kne"). By fitting the cosmic ray
spectrum data we deduce that the favorite values for the parameters of the
theory are $M_f \sim 8$ TeV and $\delta =4$.


title: B -> V gamma at NLO from QCD Factorization

abstract:
  We discuss the exclusive radiative B-meson decays B -> K* gamma and B -> rho
gamma in a model-independent manner. The analysis is based on the heavy-quark
limit of QCD. This allows a factorization of perturbatively calculable
contributions to the B -> V gamma matrix elements from non-perturbative form
factors and universal light-cone distribution amplitudes. These results allow
us to compute exclusive b -> s(d) gamma decays systematically beyond the
leading logarithmic approximation. We present results for these decays complete
to next-to-leading order in QCD and to leading order in the heavy-quark limit.
Phenomenological implications for various observables of interest are
discussed, including direct CP violation and isospin breaking effects.


title: Muon g-2 and Neutrino Mass in a New Minimal Extension of the MSSM

abstract:
  If the one term $(\hat \nu_e \hat \mu - \hat e \hat \nu_\mu) \hat \tau^c$ is
added to the MSSM (Minimal Supersymmetric Standard Model) superpotential, the
recently observed muon g--2 (anomalous magnetic moment) excess can be explained
very simply by a light $\tilde \nu_e$. If the soft symmetry-breaking terms
$\hat \nu_\alpha \hat h_2^0 - \hat l_\alpha \hat h_2^+$ are also added,
realistic neutrino masses (with bimaximal mixing) are generated as well.


title: Non-perturbative effects in semi-leptonic B_c decays

abstract:
  We discuss the impact of the soft degrees of freedom inside the B_c meson on
its rate in the semi-leptonic decay B_c -> X l nu_l where X denotes light
hadrons below the D^0 threshold. In particular we identify contributions
involving soft hadrons which are non-vanishing in the limit of massless
leptons. These contributions become relevant for a measurement of the purely
leptonic B_c decay rate, which due to helicity suppression involves a factor
m_l^2 and thus is much smaller than the contributions involving soft hadrons.


title: Low Scale Theories: Light Neutrinos and Unification of Gauge Couplings

abstract:
  Mechanism for generation of suppressed neutrino masses, within low scale
theories, is considered. The mechanism do not have extradimensional nature and
is realized through extended $SU(2)_L$ scalar multiplets. Latters, in some
cases, are also crucial for successful low scale unification.


title:
Observational constraints on the inflaton potential combined with
  flow-equations in inflaton space

abstract:
  Direct observations provide constraints on the first two derivatives of the
inflaton potential in slow roll models. We discuss how present day
observations, combined with the flow equations in slow roll parameter space,
provide a non-trivial constraint on the third derivative of the inflaton
potential. We find a lower bound on the third derivative of the inflaton
potential V'''/V > -0.2. We also show that unless the third derivative of the
inflaton potential is unreasonably large, then one predicts the tensor to
scalar ratio, r, to be bounded from below r > 3 * 10^{-6}.


title:
Anomalous chirality fluctuations in the initial stage of heavy ion
  collisions and parity odd bubbles

abstract:
  We compute numerically the topological charge distribution in the initial
stage of a high energy heavy ion collision. This charge distribution is
generated by Chern-Simons number fluctuations associated with the dynamics of
strong classical fields in the initial state. The distribution is found to be
quite narrow at RHIC and LHC energies reflecting a small value of the
topological susceptibility. Thus the effective potential of classical fields is
shallow in the $\theta$-direction likely creating favorable conditions for the
subsequent generation of P-odd bubbles.


title: Heavy Flavour Physics at HERA - a Survey

abstract:
  At the HERA collider at DESY, high energy electron and positron beams
interact with proton beams. A review is presented of the variety of ways in
which these collisions produce final states containing charm and beauty quarks.


title: A Study of Nucleon Spin Struture from Quantum Chromodynamics

abstract:
  I present an introduction to the field of Quantum Chromodynamics (QCD) with
emphasis on nucleon spin structure and perturbative methods. After a somewhat
comprehensive overview of perturbative QCD, including the systematics of
renormalization, I introduce deeply-inelastic scattering and deeply-virtual
Compton scattering along with the nonperturbative distribution functions
appearing in these processes. I show how these processes can be used to extract
the distribution of longitudinal spin of nucleons, and briefly discuss the
complications associated with transverse spin components.
  There are five appendices which accompany this work, discussing topics
ranging from canonical field quantization to dimensional regularization to the
structure of several important Lie groups. These appendices are meant to give
the reader a certain basic understanding of some of the mathematical details
underlying the main text, as well as provide a useful reference.
  This work was submitted in a slightly different form to the University of
Maryland at College Park in partial completion of the requirements for a doctor
of philosophy in physics, received August 2000.


title: Charged and superconducting vortices in dense quark matter

abstract:
  Quark matter at astrophysical densities may contain stable vortices due to
the spontaneous breaking of hypercharge symmetry by kaon condensation. We argue
that these vortices could be both charged and electrically superconducting.
Current carrying loops (vortons) could be long lived and play a role in the
magnetic and transport properties of this matter. We provide a scenario for
vorton formation in protoneutron stars.


title:
Parity nonconservation in heavy atoms: The radiative correction enhanced
  by the strong electric field of the nucleus

abstract:
  Parity nonconservation due to the nuclear weak charge is considered. We
demonstrate that the radiative corrections to this effect due to the vacuum
fluctuations of the characteristic size larger than the nuclear radius $r_0$
and smaller than the electron Compton wave-length $\lambda_C$ are enhanced
because of the strong electric field of the nucleus. The parameter that allows
one to classify the corrections is the large logarithm $\ln(\lambda_C/r_0)$.
The vacuum polarization contribution is enhanced by the second power of the
logarithm. Although the self-energy and the vertex corrections do not vanish,
they contain only the first power of the logarithm. The value of the radiative
correction is 0.4% for Cs and 0.9% for Tl, Pb, and Bi. We discuss also how the
correction affects the interpretation of the experimental data on parity
nonconservation in atoms.


title: Implication of Brane fluctuations to indirect collider signals

abstract:
  We study the effect of brane fluctuation on the indirect signals of high
energy colliders. Brane fluctuation could act as a regulator of divergent
expression of infinite tower of Kaluza-Klein graviton effects. The
phenomenological parameter $\lambda$, introduced by Hewett, is shown to be
determined in our setting, and its dramatic behaviors depending on the
$D=4+\delta$ dimensional gravitation scale $M_D$, `softening parameter'
$\Delta$, and $\sqrt{s}$ of collider are presented. The present exclusion
bounds from the processes $e^+e^-\to \gamma\gamma$ and $p\bar{p}\to e^+ e^-,
\gamma\gamma(\gamma)$ are considered within the parameter space $(M_D, \Delta)$
with respect to the number of extra dimensions.


title:
Phenomenological Applications of QCD Factorization to Semi-inclusive B
  Decays

abstract:
  We have systematically investigated the semi-inclusive B decays $B\to MX$,
which are manifestations of the quark decay $b \to Mq$, within a framework
inspired by QCD-improved factorization. These decays are theoretically clean
and have distinctive experimental signatures. We focus on a class of these that
do not require any form factor information and therefore may be especially
suitable for extracting information on the angles $\alpha$ and $\gamma$ of the
unitarity triangle. The strong phase coming from final-state rescattering due
to hard gluon exchange between the final states can induce large rate
asymmetries for tree-dominated color-suppressed modes
$(\pi^0,\rho^0,\omega)X_{\bar s}$. The nonfactorizable hard spectator
interactions in the 3-body decay $B\to Mq_1\bar q_2$, though phase-space
suppressed, are extremely important for the tree-dominated modes
$(\pi^0,\rho^0,\omega)X_{\bar s},~\phi X$, $J X_s,J X$ and the
penguin-dominated mode $\omega X_{s\bar s}$. Our result for ${\cal B}(B\to J
X_s)$ is in agreement with experiment. $B^0_s\to (\pi^0,\rho^0,\omega)X_{\bar
s}$, $\rho^0X_{s\bar s}$, $B^0\to(K^-X,K^{*-}X)$ and $B^-\to
(K^0X_s,K^{*0}X_s)$ are the most promising ones in searching for direct CP
violation: they have branching ratios of order $10^{-6}-10^{-4}$ and CP rate
asymmetries of order $(10-40)%$.


title: Sudakov effects in B -> pi l nu form factors

abstract:
  In order to obtain information about the Standard Model from exclusive
hadronic two-body B-decays, we have to quantify non-perturbative QCD effects.
Approaches based on the factorization of mass singularities into hadronic
distribution amplitudes and form factors provide a rigorous theoretical
framework for the evaluation of these effects in the heavy quark limit. But it
is not possible to calculate power corrections in a model-independent way,
because of non-factorizing long-distance contributions. It has been argued that
Sudakov effects suppress these contributions and render the corresponding
corrections perturbatively calculable. In this paper we examine this claim for
the related example of semileptonic B -> pi decays and conclude that it is not
justified. The uncertainties in our knowledge of the mesons' distribution
amplitudes imply that the calculations of the form factors are not sufficiently
precise to be useful phenomenologically. Moreover, a significant contribution
comes from the non-perturbative region of large impact parameters, and is
therefore uncalculable. We also raise a number of theoretical issues in the
derivation of the underlying formalism. For B-decays it is thus not possible to
invoke Sudakov effects to calculate amplitudes for decays which have
long-distance divergences (end-point singularities) in the standard
hard-scattering approach.


title:
Out of Equilibrium Non-perturbative Quantum Field Dynamics in
  Homogeneous External Fields

abstract:
  The quantum dynamics of the symmetry broken lambda (Phi^2)^2 scalar field
theory in the presence of an homogeneous external field is investigated in the
large N limit. We choose as initial state the ground state for a constant
external field J .The sign of the external field is suddenly flipped from
  J to - J at a given time and the subsequent quantum dynamics calculated.
Spinodal instabilities and parametric resonances produce large quantum
fluctuations in the field components transverse to the external field. This
allows the order parameter to turn around the maximum of the potential for
intermediate times. Subsequently, the order parameter starts to oscillate near
the global minimum for external field - J, entering a novel quasi-periodic
regime.


title:
Constraint supersymmetry Breaking and Non-perturbative Effects in String
  Theory

abstract:
  We discuss supersymmetry breaking mechanisms at the level of low energy N=1
effective heterotic superstring actions that exhibit $SL(2,Z)_T$ target space
modular duality or $SL(2,Z)_S$ strong-weak coupling duality. The allowed
superpotential forms use the assumption that the source of non-perturbative
effects is not specified and as a result represent the most general
parametrization of non-perturbative effects. The minimum values of the limits
on the parameters in the superpotential may correspond to vacua with vanishing
cosmological constant.


title: Confronting Heavy Tau Neutrinos with Neutrino Oscillations

abstract:
  If the tau neutrino is as heavy as 10 MeV which may have certain
astrophysical implications, the neutrino mass pattern is studied so as to
accommodate the new oscillation observations. It predicts that the electron
neutrino has Marjorana mass around 0.05 eV. A supersymmetric model is described
to realize the above scenario.


title: See-saw Mechanisms for Dirac and Majorana Neutrino Masses

abstract:
  We investigate the see-saw mechanism for generally non-fine-tuned $n \times
n$ mass matrices involving both Dirac and Majorana neutrinos. We specifically
show that the number of naturally light neutrinos cannot exceed half of the
dimension of the considered mass matrix. Furthermore, we determine a criterion
for mass matrix textures leading to light Dirac neutrinos with the see-saw
mechanism. Especially, we study $4 \times 4$ and $6 \times 6$ mass matrix
textures and give some examples in order to highlight these types of textures.
Next, we present a model scheme based on non-Abelian and discrete symmetries
fulfilling the above mentioned criterion for light Dirac neutrinos. Finally, we
investigate the connection between symmetries and the invariants of a mass
matrix on a formal level.


title: Comment on `Analysis of O(p^2) Corrections to <2pi|Q_{7,8}|K>'

abstract:
  We extend in several respects our earlier work on O(p^2) corrections to
matrix elements of the electroweak penguin operator O_{ewp}. First, to
facilitate comparison with certain lattice studies we calculate O(p^2)
corrections to <pi|O_{ewp}|K> in the SU(3) limit of equal light quark masses.
Next, we demonstrate how an apparent disagreement in the literature regarding
whether higher order chiral contributions increase or decrease
<2pi_{I=2}|O_{ewp}|K> is simply a consequence of how the leading order chiral
amplitude is defined. Finally, we address an aspect of the epsilon'/epsilon
problem by estimating O(p^2) corrections to recent determinations of
<2pi_{I=2}|Q_{7,8}|K> which were carried out in the chiral limit.


title:
An Alternative Approach to Semi-inclusive DIS and A Model Independent
  Determination of D_u^{\pi^+}, D_d^{\pi^+} and D_s^{\pi^+}

abstract:
  We discuss how to extract the polarized parton densities and fragmentation
functions in a model independent way from SIDIS, and present results for
D_{u,d,s}^{\pi^+}.


title: HTL quasiparticle picture of the thermodynamics of QCD

abstract:
  Starting from a nonperturbative expression for entropy and density obtained
from $\Phi$-derivable two-loop approximations to the thermodynamic potential, a
quasiparticle model for the thermodynamics of QCD can be developed which
incorporates the physics of hard thermal loops and leads to a reorganization of
the otherwise ill-behaved thermal perturbation theory through order
$\alpha_s^{3/2}$. Some details of this reorganization are discussed and the
differences to simpler quasiparticle models highlighted. A comparison with
available lattice data shows remarkable agreement down to temperatures of $\sim
2.5 T_c$.


title: A joint analysis of the S-wave in the pi+pi- and pi0pi0 data

abstract:
  We use our former results on pi+pi- S-wave obtained in a nearly
assumption-free way from the 17.2 GeV/c data to predict the pi0pi0 S--wave. The
predictions are compared with the recent results of the E852 experiment at 18.3
GeV/c. A good agreement is found for only one (the "down-flat") solution while
the second one (the "up-flat") is excluded by the pi0pi0 data. Thus the
long-standing "up-down" ambiguity has been finally resolved in favour of the
S-wave intensity which stays large and nearly constant up to the KK-bar
threshold. A joint analysis of both sets of data leads to a reduction of errors
for this solution.


title:
Next-to-leading order QCD corrections to $bg \to t W^-$ at the CERN
  Large Hadron Collider

abstract:
  The next-to-leading order QCD corrections to the Standard Model process of
single top production,
  $bg \to t W^-$, for the CERN Large Hadron Collider with $\sqrt{s}=14$ TeV
have been calculated. For renormalization and factorization scales $\mu=\mu_0$
($\mu_0=m_t+m_W$), the NLO hadronic cross section is $\sim 37 $ pb, while $\sim
25 $ pb for tree level. The NLO QCD corrections can enhance the cross section
by a factor from 1.33 to 1.66 for $\frac{\mu_0}{2} < \mu < 2 \mu_0$.


title: Verifiable Origin of Neutrino Mass at TeV Scale

abstract:
  The physics responsible for neutrino mass may reside at or below the TeV
energy scale. The neutrino mass matrix in the $(\nu_e, \nu_\mu, \nu_\tau)$
basis may then be deduced from future high-energy accelerator experiments. The
newly observed excess in the muon anomalous magnetic moment may also be
related.


title: Do Quark Mass Effects Survive in the High-$Q^2$ Limit of DIS?

abstract:
  Quark mass effects are analyzed at high $Q^2$ in the current fragmentation
region of DIS. It is found that the linear combination $F_2-2.75F^c_2$ scales
at large $Q^2$ and small $x$. We obtained a lower bound for the ratio
$F^c_2/F_2$ which lies very close to the data from HERA.


title: Unification in models with replicated gauge groups

abstract:
  We examine unification of gauge couplings in four dimensional renormalizable
gauge theories inspired by the latticized (deconstructed) SM or MSSM in five
dimensions. The models are based on replicated gauge groups, spontaneously
broken to the diagonal subgroup. The analysis is performed at one-loop level,
with the contribution from the heavy vector bosons included, and compared with
the analogous results in the SM or MSSM. Unification at or above the diagonal
breaking scale is discussed. We find that in the considered class of extensions
of the SM(MSSM) unification is possible for a wide range of unification scales
and with the similar accuracy as in the SM(MSSM). Unification above the
diagonal breaking scale is particularly attractive: it is a consequence of the
SM(MSSM) unification, but with the unification scale depending on the number of
replications of the gauge group.


title:
Hyperfine Structure of the Ground and First Excited States in Light
  Hydrogen-Like Atoms and High-Precision Tests of QED

abstract:
  We consider hyperfine splitting of 1s and, in part, of 2s levels in light
hydrogen-like atoms: hydrogen, deuterium, tritium, helium-3 ion, muonium and
positronium. We discuss present status of precision theory and experiment for
the hfs intervals. We pay a special attention to a specific difference, D_{21}
= 8 E_{hfs}(2s) - E_{hfs}(1s), which is known experimentally for hydrogen,
deuterium and ^3He^+ ion. The difference is weakly affected by the effects of
the nuclear structure and thus may be calculated with a high accuracy. We
complete a calculation of the fourth order QED contributions to this difference
and present here new results on corrections due to the nuclear effects. Our
theoretical predictions appear to be in a fair agreement with available
experimental data. Comparison of the experimental data with our examination of
D_{21} allows to test the state-dependent sector of theory of the hfs
separation of the 1s and 2s levels in the light hydrogen-like atoms up to
10^-8.


title: The Nucleon-Nucleon Interaction and Large N_c QCD

abstract:
  The nature of the nonrelativistic nucleon-nucleon potential in the large N_c
limit is discussed. In particular, we address the consistency of the meson
exchange picture of nucleon interactions. It is shown that the nonrelativistic
nucleon-nucleon potential extracted from the Feynmann graphs up to and
including two-meson exchange diagrams satisfies the spin-flavor counting rules
of Kaplan and Savage, and Kaplan and Manohar, provided the nucleon momenta is
of order N_{c}^{0}. The key to this is a cancelation of the retardation effect
of the box graphs against the contributions of the crossed-box diagram. The
consistency requires including $\Delta$ as an intermediate state.


title:
A few comments after the charged current measurement at the Sudbury
  Neutrino Observatory

abstract:
  The comparison of the SNO charged current result with the solar neutrino
signal measured by Super-Kamiokande has provided, for the first time, the
evidence of a non electron flavour active neutrino component in the solar flux.
We remark here that this evidence can be obtained in a model independent way,
i.e. without any assumpion about solar models, about the energy dependence of
the neutrino oscillation probability and about the presence of sterile
neutrinos. Furthermore, from the 8B neutrino flux obtained by combining SNO and
Super-Kamiokande, one can determine the central solar temperature, T = 1.57 (1
\pm 1%) 10^7 K, and provide an estimate of the beryllium neutrino flux, Phi_Be
= 4.9 (1 \pm 11%) 10^9 cm^{-2} s^{-1}.


title: Oscillating scalar-field dark matter in supergravity

abstract:
  We show that an oscillating scalar field in supergravity of mass of the order
of $\sim$ TeV with a nonzero vacuum expectation value ($\sim 10^{10}$ GeV) can
be a candidate of cold dark matter (CDM). To avoid the gravitino problem, we
need a low reheating temperature after the primordial inflation. Then, the
energy density of the oscillating scalar field satisfies all the requirements
for CDM at present in the universe.


title:
Two Detector Reactor Neutrino Oscillation Experiment Kr2Det at
  Krasnoyarsk. Status Report

abstract:
  We consider status of the Kr2Det project aimed at sensitive searches for
neutrino oscillations in the atmospheric neutrino mass parameter region around
Dm2 ~ 3x10-3 eV2and at obtaining new information on the electron neutrino mass
structure (Ue3).


title:
Temperature Dependence of Gluon and Quark Condensates as from Linear
  Confinement

abstract:
  The gluon and quark condensates and their temperature dependence are
investigated within QCD premises. The input for the former is a gauge invariant
$gg$ kernel made up of the direct (D), exchange (X) and contact(C) QCD
interactions in the lowest order, but with the perturbative propagator $k^{-2}$
replaced by a `non-perturbative $k^{-4}$ form obtained via two
differentiations: $ \mu^2 \partial_m^2 (m^2+k^2)^{-1}$, ($\mu$ a scale
parameter), and then setting $m=0$, to simulate linear confinement. Similarly
for the input $q{\bar q}$ kernel the gluon propagator is replaced by the above
$k^{-4}$ form. With these `linear' simulations, the respective condensates are
obtained by `looping' up the gluon and quark lines in the standard manner.
Using Dimensional regularization (DR), the necessary integrals yield the
condensates plus temperature corrections, with a common scale parameter $\mu$
for both. For gluons the exact result is $$ <GG> =
{36\mu^4}\pi^{-3}\alpha_s(\mu^2)[2-\gamma - 4\pi^2 T^2/(3\mu^2)]$$. Evaluation
of the quark condensate is preceded by an approximate solution of the SDE for
the mass function $m(p)$, giving a recursive formula, with convergence achieved
at the third iteration. Setting the scale parameter $\mu$ equal to the
universal Regge slope $1 GeV^2$, the gluon and quark condensates at T=0 are
found to be $0.586 Gev^4$ and $(240-260 MeV)^3$ respectively, in fair accord
with QCD sum rule values. Next, the temperature corrections (of order $-T^2$
for both condensates) is determined via finite-temperature field theory a la
Matsubara. Keywords: Gluon Condensate, mass tensor, gauge invariance, linear
confinement, finite-temperature, contour-closing. PACS: 11.15.Tk ; 12.38.Lg ;
13.20.Cz


title:
Exact Differential O(alpha**2) Results for Hard Bremsstrahlung in e+e-
  Annihilation to 2f At and Beyond LEP2 Energies

abstract:
  We present the exact O(alpha) correction to the process e+ e- -> f f-bar +
gamma, f neq e, for ISR oplus FSR at and beyond LEP2 energies. We give explicit
formulas for the completely differential cross section. As an important
application, we compute the size of the respective sub-leading corrections of
O(alpha L) to the f f-bar cross section, where L is the respective big
logarithm in the renormalization group sense so that it is identifiable as L =
ln |s|/m_e^2 when s is the squared e+e- cms energy. Comparisons are made with
the available literature. We show explicitly that our results have the correct
infrared limit, as a cross-check. Some comments are made about the
implementation of our results in the framework of the Monte Carlo event
generator KK MC.


title: Large-Nc Methods in Kaon Physics

abstract:
  This talk reviews recent progress in formulating the dynamics of Kaon
Physics, within the framework of the 1/Nc-expansion in QCD.


title:
The lepton pair production in heavy ion collisions in perturbation
  theory

abstract:
  We derive the first terms in the amplitude of lepton pair production in the
Coulomb fields of two relativistic heavy ions. Using the Sudakov technique,
which very simplify the calculations in momentum space for the processes at
high energies, we get the compact analytical expressions for differential cross
section of the process under consideration in the lowest order in fine
structure constant (Born approximation) valid for any momentum transfer and in
a wide kinematics region for produced particles. Exploiting the same technique
we consider the next terms of perturbation series (up to fourth order in fine
structure constant) and investigate their energy dependence and limiting cases.
It has been shown that taking in account all relevant terms in corresponding
order one obtains the expressions which are gauge invariant and finite. We
estimate the contribution of the Coulomb corrections to the total cross section
and discuss the cancellations of the different terms which holds in the total
cross section.


title: Jet fragmentation in e^+e^- annihilation

abstract:
  A short review of theoretical and experimental results on fragmentation in
e^+e^- annihilation is presented. Starting with an introduction of the concept
of fragmentation functions in e^+e^- annihilation, aspects of scaling
violation, multiplicities, small and large x, longitudinal, gluon, light and
heavy quark fragmentation are summarized.


title:
Loop induced Higgs and Z boson couplings to Neutralinos and implications
  for collider and Dark Matter searches

abstract:
  We calculate the one-loop induced couplings of two gaugino-like neutralinos
to the $Z$ and Higgs bosons in the Minimal Supersymmetric Standard Model. These
couplings, which vanish at the tree level, can be generated through loops
involving fermions and sfermions. We show that, while the neutralino
contribution to the invisible $Z$ boson decay width remains small, the loop
induced couplings to the lightest Higgs boson might be sufficiently large to
yield a rate of invisible decays of this Higgs boson that should be detectable
at future $e^+e^-$ colliders. We also study the implications of these couplings
for direct searches of Dark Matter and show that they can modify appreciably
the neutralino-nucleon elastic cross section for some parameter range.


title: Reliability of K --> Pi Pi matrix element calculations

abstract:
  I demonstrate that the short distance contribution to K --> Pi Pi decays must
be supplemented with large distance effects. A hybrid calculation is outlined
based on QCD diagrams supplemented by chiral contributions and Pi-Pi
phaseshifts.


title:
Relativistic Three-Quark Bound States in Separable Two-Quark
  Approximation

abstract:
  Baryons as relativistic bound states in 3-quark correlations are described by
an effective Bethe-Salpeter equation when irreducible 3-quark interactions are
neglected and separable 2-quark correlations are assumed. We present an
efficient numerical method to calculate the nucleon mass and its covariant wave
function in this quantum field theoretic quark-diquark model with
quark-exchange interaction. Expanding the components of the spinorial wave
function in terms of Chebyshev polynomials, the four-dimensional integral
equations are in a first step reduced to a coupled set of one-dimensional ones.
This set of linear and homogeneous equations defines a generalised eigenvalue
problem. Representing the eigenvector corresponding to the largest eigenvalue,
the Chebyshev moments are then obtained by iteration. The nucleon mass is
implicitly determined by the eigenvalue, and its covariant wave function is
reconstructed from the moments within the Chebyshev approximation.


title: Isospin Violation and the Magnetic Moment of the Muon

abstract:
  We calculate the leading isospin-violating and electromagnetic corrections
for the decay tau --> pi^0 pi nu_tau at low energies. The corrections are small
but relevant for the inclusion of tau decay data in the determination of
hadronic vacuum polarization especially for the anomalous magnetic moment of
the muon.


title: Cosmic Rays as Probes of Large Extra Dimensions and TeV Gravity

abstract:
  If there are large extra dimensions and the fundamental Planck scale is at
the TeV scale, then the question arises of whether ultra-high energy cosmic
rays might probe them. We study the neutrino-nucleon cross section in these
models. The elastic forward scattering is analyzed in some detail, hoping to
clarify earlier discussions. We also estimate the black hole production rate.
We study energy loss from graviton mediated interactions and conclude that they
can not explain the cosmic ray events above the GZK energy limit. However,
these interactions could start horizontal air showers with characteristic
profile and at a rate higher than in the Standard Model.


title: Lower Limits on Soft Supersymmetry-Breaking Scalar Masses

abstract:
  Working in the context of the CMSSM, we argue that phenomenological
constraints now require the universal soft supersymmetry-breaking scalar mass
m_0 be non-zero at the input GUT scale. This conclusion is primarily imposed by
the LEP lower limit on the Higgs mass and the requirement that the lightest
supersymmetric particle not be charged. We find that m_0 > 0 for all tan beta
if mu < 0, and m_0 = 0 may be allowed for mu > 0 only when tan beta sim 8 and
one allows an uncertainty of 3+ GeV in the theoretical calculation of the Higgs
mass. Upper limits on flavour-changing neutral interactions in the MSSM squark
sector allow substantial violations of non-universality in the m_0 values, even
if their magnitudes are comparable to the lower limit we find in the CMSSM.
Also, we show that our lower limit on m_0 at the GUT scale in the CMSSM is
compatible with the no-scale boundary condition m_0 = 0 at the Planck scale.


title: Intrinsic Charm Flavor and Helicity Content in the Proton

abstract:
  Contributions to the quark flavor and spin observables from the intrinsic
charm in the proton are discussed in the SU(4) quark meson fluctuation model.
Our results suggest that the probability of finding the intrinsic charm in the
proton is less than 1%. The intrinsic charm helicity is small and negative,
$\Delta c \simeq -(0.003\sim 0.015)$. The fraction of the total quark helicity
carried by the intrinsic charm is less than 2%, and $c_\up/c_\dw$=35/67.


title:
Results for all reactions e+ e- -> 4f, 4f + gamma with nonzero fermion
  masses

abstract:
  We accomplish our efforts to obtain predictions for all four-fermion final
states of e+ e- annihilation and the corresponding bremsstrahlung reactions
which are possible in the framework of the Standard Model. For this purpose we
have developed a program EE4FGAMMA. Our predictions are valid for fermions of
arbitrary masses and we can obtain results for total cross sections without any
collinear cut. Keeping exact fermion masses is of course required for top quark
production. We give a detailed phenomenological analysis of fermion mass
effects and real photon radiation for all channels of four-fermion production
at LEP-II and next linear collider energies.


title: Indirect heavy SUSY signals in Higgs and top decays

abstract:
  We summarize the recent results on the supersymmetric QCD radiative
corrections, at the one-loop level, in Higgs and top quark decays, in the
context of the Minimal Supersymmetric Standard Model and in the decoupling
limit of very heavy SUSY particles. Special attention is devoted to the
particular decays $h^0\to b \bar b$, $H^+\to t \bar b$, $H^0\to b \bar b$,
$A^0\to b \bar b$ and $t \to H^+\bar b$ where the radiative corrections from
heavy squarks and heavy gluinos do not decouple and are enhanced at large $\tan
\beta$. Some interesting phenomenological consequences are also briefly
summarized.


title: Leptogenesis and Low-energy Observables

abstract:
  We relate leptogenesis in a class of theories to low-energy experimental
observables: quark and lepton masses and mixings. With reasonable assumptions
motivated by grand unification, one can show that the CP-asymmetry parameter
takes a universal form. Furthermore the dilution mass is related to the light
neutrino masses. Overall, these models offer a natural explanation for a lepton
asymmetry in the early universe.


title: Generating the curvature perturbation without an inflaton

abstract:
  We present a mechanism for the origin of the large-scale curvature
perturbation in our Universe by the late decay of a massive scalar field, the
curvaton. The curvaton is light during a period of cosmological inflation, when
it acquires a perturbation with an almost scale-invariant spectrum. This
corresponds initially to an isocurvature density perturbation, which generates
the curvature perturbation after inflation when the curvaton density becomes a
significant fraction of the total. The isocurvature density perturbation
disappears if the curvaton completely decays into thermalised radiation. Any
residual isocurvature perturbation is 100% correlated with the curvature. The
same mechanism can also generate the curvature perturbation in pre big
bang/ekpyrotic models, provided that the curvaton has a suitable non-canonical
kinetic term so as to generate a flat spectrum.


title:
Exponential Growth of Particle Number far from the Parametric Resonance
  Regime

abstract:
  Parametric resonance has received a considerable amount of interest as a good
mathematical model to describe the initial stages of the reheating phase
(matter creation) in inflationary cosmology. It is also known that exponential
particle creation can occur in situations which do not fall in the parametric
resonance regime characterized by oscillations of the inflaton field about its
minimum. Here we present a new analytical approach to exponential particle
production which can occur when the inflaton is far from the minimum of its
potential. Crucial for this effect is a term in the equation of motion which
acts like a negative mass square term, as occurs for tachyonic preheating and
negative coupling particle production. Our techniques apply in models with a
strong coupling between matter fields $\chi$ and the inflaton $\phi$, or in
some models in which the inflaton has a large amplitude of oscillation. Note
that our analysis yields results which are quite model dependent. Exponential
growth occurs in a model with interaction Lagrangian $-g M_{pl}\phi\chi^2$.
However, for the interaction Lagrangian $-g^2\phi^2\chi^2$, our formalism shows
that in the large coupling limit there can only be exponential particle
production when $\phi$ crosses 0.


title: Energy Flow in Interjet Radiation

abstract:
  We study the distribution of transverse energy, Q_Omega, radiated into an
arbitrary interjet angular region, Omega, in high-p_T two-jet events. Using an
approximation that emphasizes radiation directly from the partons that undergo
the hard scattering, we find a distribution that can be extrapolated smoothly
to Q_Omega=Lambda_QCD, where it vanishes. This method, which we apply
numerically in a valence quark approximation, provides a class of predictions
on transverse energy radiated between jets, as a function of jet energy and
rapidity, and of the choice of the region Omega in which the energy is
measured. We discuss the relation of our approximation to the radiation from
unobserved partons of intermediate energy, whose importance was identified by
Dasgupta and Salam.


title: Chiral Symmetry of Baryons

abstract:
  We study chiral symmetry aspects of the positive and negative parity baryons
by identifying them with linear representations of the chiral group $SU(N_{f})
\otimes SU(N_{f})$. It is shown that there are two distinctive schemes: naive
and mirror assignments. We construct linear sigma models for baryons in the two
assignments and examine their physical implications. Then we investigate
properties of the naive and mirror nucleons microscopically by using QCD
interpolating fields. Finally, we propose experiments to distinguish the two
chiral assignments for the nucleon.


title: Colour chiral solitons in low energy QCD

abstract:
  We derive an effective colour chiral action with a background gauge field.
The action describes configurations of soliton-skyrmion type. Kinetic term
constant $f_0^2$, analogue of $f_\pi ^2$, is a phenomenological dimensional
parameter of the model; $d=4$ terms are unique up to the choice of background
gauge field. The case of SU(2) colour group is discussed in detail. We study an
isolated configuration, i.e. a configuration in a background field which is the
vacuum field forming the gluon condensate. Thereby we introduce the condensate
energy as a second parameter and scale. Compared with the case of flavor
skyrmion configuration, the colour chiral action contains a piece with slowly
decreasing terms coming from the background vacuum field. Asymptotic behaviour
at large distances shows exponential decrease for the case of chromomagnetic
condensates and periodic otherwise . This defines a stability region for a
colour soliton. The mass is given by the positive definite integrand for a
soliton of purely bosonization origin. Contribution from the Yang-Mills action
of the background colour field has the sign opposite to bosonization part. The
baryon number current is not influenced by the background field and leads to
the standard baryon number $B=N_F/N_C$ . For $B=1/3$ we evaluated the estimate
from above $M\approx 460$ $Mev$ .


title:
The failure of cosmological perturbation theory in the new ekpyrotic and
  cyclic ekpyrotic scenarios

abstract:
  Cosmological perturbation theory fails in the new ekpyrotic and cyclic
ekpyrotic scenarios, before the scale factor of the Universe reaches zero. As a
result, a recently-proposed recipe for evolving the curvature perturbation
through the bounce in these scenarios cannot be justified.


title: A note on two-loop effects in the DMSSM

abstract:
  We investigate the proposed ``D-brane alternative'' to the MSSM model (DMSSM)
which is a type II B string orientifold model with N=1 supersymmetry, three
generations and a $SU(3)\times SU(2)_R\times SU(2)_L \times U(1)_{B-L}$ gauge
group. An accurate analysis at two-loop level is performed to show that
unification constraints predict a ``left-right'' symmetry breaking scale in the
TeV region. The exact value of this scale is the result of the competing
effects of the two loop terms against the low energy supersymmetric threshold
effects. The model accommodates logarithmic unification of the gauge couplings
at an intermediate scale of $10^{12}$ GeV and the necessary conditions to
achieve this are addressed.


title: Jet Production at HERA

abstract:
  I review the status of perturbative QCD calculations for jet production in
eP-scattering at HERA. I will discuss possibilities of combining fixed order,
especially higher order, calculations and parton showers.


title: Particle spectrum in modified NMSSM

abstract:
  The restrictions on the lightest Higgs boson mass in the minimal
supersymmetric models are briefly reviewed. The particle spectrum is considered
in the framework of the simplest modification of NMSSM that allows to avoid the
domain wall problem and to get the self--consistent solution in the strong
Yukawa coupling limit. The lightest Higgs boson mass in the investigated model
can reach $125 GeV$ at values of $\tan\beta\ge 1.9$ and does not exceed
$130.5\pm 3.5 GeV$.


title: Limits on the Non-commutativity Scale

abstract:
  A non-vanishing vacuum expectation value for an antisymmetric tensor field
leads to the violation of Lorentz invariance, controlled by the dimension (-2)
parameter, theta_{mu nu}. We assume that the zeroth order term in
theta-expansion represents the Standard Model and study the effects induced by
linear terms in theta_{mu nu}. If coupling to theta_{mu nu} is realized in
strongly interacting sector of the theory, the clock comparison experiments
place the limit on the possible size of this background at the level of
1/\sqrt{theta}>~5X10^{14} GeV. If the interaction with theta_{mu nu} is
initially present only in the QED sector, this limit can be relaxed to
10^{11}-10^{12} GeV level. The strength of these limits obviates the
inferiority of collider physics with regard to experimental checks of Lorentz
invariance. Limits of similar strength are expected to hold in the case of
mixed non-commutativity between four-dimensional and extra-dimensional
coordinates. We also show that in certain models mixed non-commutativity can be
interpreted as 4d CPT-violating background.


title:
Dynamics near the critical point: the hot renormalization group in
  quantum field theory

abstract:
  The perturbative approach to the description of long wavelength excitations
at high temperature breaks down near the critical point of a second order phase
transition. We study the \emph{dynamics} of these excitations in a relativistic
scalar field theory at and near the critical point via a renormalization group
approach at high temperature and an $\epsilon$ expansion in $d=5-\epsilon$
space-time dimensions. The long wavelength physics is determined by a
non-trivial fixed point of the renormalization group. At the critical point we
find that the dispersion relation and width of quasiparticles of momentum $p$
is $\omega_p \sim p^{z}$ and $\Gamma_p \sim (z-1) \omega_p$ respectively, the
group velocity of quasiparticles $v_g \sim p^{z-1}$ vanishes in the long
wavelength limit at the critical point. Away from the critical point for
$T\gtrsim T_c$ we find $\omega_p \sim \xi^{-z}[1+(p \xi)^{2z}]^{{1/2}}$ and
$\Gamma_p \sim (z-1) \omega_p \frac{(p \xi)^{2z}}{1+(p \xi)^{2z}}$ with $\xi$
the finite temperature correlation length $ \xi \propto |T-T_c|^{-\nu}$. The
new \emph{dynamical} exponent $z$ results from anisotropic renormalization in
the spatial and time directions. For a theory with O(N) symmetry we find $z=1+
\epsilon \frac{N+2}{(N+8)^2}+\mathcal{O}(\epsilon^2)$. Critical slowing down,
i.e, a vanishing width in the long-wavelength limit, and the validity of the
quasiparticle picture emerge naturally from this analysis.


title:
Vacuum condensate of mass dimension 2 as the origin of mass gap and
  quark confinement (A review)

abstract:
  This is a brief summary of recent works on the possibility of vacuum
condensate of mass dimension 2 in Yang-Mills theory as the gluon sector of QCD.
In particular, I discuss the physical implications due to this condensate,
especially, for the mass gap and quark confinement. This talk is mainly based
on a recent paper [1] and papers in preparation [2].


title: Positivity constraints on photon structure functions

abstract:
  We investigate the positivity constraints for the structure functions of both
virtual and real photon. From the Cauchy-Schwarz inequality we derive three
positivity conditions for the general virtual photon case, which reduce, in the
real photon case, to one condition relating the polarized and unpolarized
structure functions.


title:
LHC(CMS) SUSY discovery potential for the case of nonuniversal gaugino
  masses

abstract:
  We investigate squark and gluino pair production at LHC(CMS) for the case of
nonuniversal gaugino masses. Visibility of signal by an excess over SM
background in $(n \geq 2)jets + E^{miss}_T + (m \geq leptons)$ 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 close to
squark or gluino masses it is possible to detect SUSY for $(m_{\tilde{q}},
m_{\tilde{g}}) \leq (1 - 1.5)$ TeV.}


title: Symplectic vs pseudo-orthogonal structure of space-time

abstract:
  The advantages to consider the ordinary space-time as the symplectic rather
than pseudo-orthogonal one are indicated, and the consequences of extending
this view to extra space/time dimensions are discussed.


title:
$B\to \tau^+ \tau^- \gamma $ decay in the general two Higgs doublet
  model including the neutral Higgs boson effects

abstract:
  We investigate the differential branching ratio, branching ratio,
differential forward-backward asymmetry, the forward-backward asymmetry of the
lepton pair and the lepton polarization asymmetry of the exclusive $B\to \tau^+
\tau^- \gamma$ decay in the general two Higgs doublet model including the
neutral Higgs boson effects. We analyse the dependencies of these quantities on
the model parameters and also on the neutral Higgs boson effects. We found that
they get considerable enhancement from the two Higgs doublet model compared to
the standard model and neutral Higgs boson effects are quite sizable.


title: Flat directions in susy guts

abstract:
  It is shown that a realistic SUSY SU(6) GUT can dynamically generate the GUT
scale and solve at the same time the doublet-triplet splitting problem. The
cosmological implications of such a model are briefly reviewed.


title:
eta and eta' in a coupled Schwinger-Dyson and Bethe-Salpeter approach.
  II. The gamma^* gamma transition form factors

abstract:
  The applications of the consistently coupled Schwinger-Dyson and
Bethe-Salpeter approach to the eta-eta' complex are extended to the two-photon
transition form factors of eta and eta' for spacelike transferred momenta. We
compare our predictions with experiment and some other theoretical approaches.


title:
Improving the discovery potential of charged Higgs bosons at Tevatron
  Run 2

abstract:
  By exploiting the full process $p\bar p\to t\bar b H^-$, in place of the
standard Monte Carlo procedure of factorising production and decay, $p\bar p\to
t\bar t$ followed by $\bar t\to\bar b H^-$, we show how to improve the
discovery reach of the Tevatron (Run 2) in charged Higgs boson searches, in the
large $\tan\beta$ region. This is achieved in conjunction with dedicated cuts
on a `transverse mass' distribution sensitive to the Higgs boson mass and to
`polarisation' effects in the $H^-\to\tau^-\bar\nu_\tau$ decay channel.


title: High Transverse Momentum Physics at the Large Hadron Collider

abstract:
  This note summarizes many detailed physics studies done by the ATLAS and CMS
Collaborations for the LHC, concentrating on processes involving the production
of high mass states. These studies show that the LHC should be able to
elucidate the mechanism of electroweak symmetry breaking and to study a variety
of other topics related to physics at the TeV scale. In particular, a Higgs
boson with couplings given by the Standard Model is observable in several
channels over the full range of allowed masses. Its mass and some of its
couplings will be determined. If supersymmetry is relevant to electroweak
interactions, it will be discovered and the properties of many supersymmetric
particles elucidated. Other new physics, such as the existence of massive gauge
bosons and extra dimensions can be searched for extending existing limits by an
order of magnitude or more.