title:
A critique of the angular momentum sum rules and a new angular momentum
  sum rule

abstract:
  We present a study of the tensorial structure of the hadronic matrix elements
of the angular momentum operators $\bm{J}$. Well known results in the
literature are shown to be incorrect, and we have taken pains to derive the
correct expressions in three different ways, two involving explicit physical
wave packets and the third, totally independent, based upon the rotational
properties of the state vectors. Surprisingly it turns out that the results are
very sensitive to the type of relativistic spin state used to describe the
motion of the particle i.e. whether a canonical (i.e. boost) state or a
helicity state is utilized. We present results for the matrix elements of the
angular momentum operators, valid in an arbitrary Lorentz frame, both for
helicity states and canonical states.
  These results are relevant for the construction of angular momentum sum
rules, relating the angular momentum of a nucleon to the spin and orbital
angular momentum of its constituents. It turns out that it is necessary to
distinguish carefully whether the motion of the partons is characterized via
canonical or helicity spin states. Fortunately, for the simple parton model
interpretation, when the proton moves along $OZ$, our results for the sum rule
based upon the matrix elements of $J_z$ agree with the often used sum rule
found in the literature. But for the components $J_x, J_y$ the results are
different and lead to a new and very intuitive sum rule for transverse
polarization.


title:
Transport equations for chiral fermions to order \hbar and electroweak
  baryogenesis: Part II

abstract:
  This is the second in a series of two papers. While in Paper I we derive
semiclassical Boltzmann transport equations and study their flow terms, here we
address the collision terms. We use a model Lagrangean, in which fermions
couple to scalars through Yukawa interactions and approximate the self-energies
by the one-loop expressions. This approximation already contains important
aspects of thermalization and scatterings required for quantitative studies of
transport in plasmas. We compute the CP-violating contributions to both the
scalar and the fermionic collision term.


title: Neutrino Oscillations in Intermediate States.II -- Wave Packets

abstract:
  We analyze oscillations of intermediate neutrinos in terms of the scattering
of particles described by Gaussian wave packets. We study a scalar model as in
a previous paper (I) but in realistic situations, where the two particles of
the initial state and final state are wave packets and neutrinos are in the
intermediate state. The oscillation of the intermediate neutrino is found from
the time evolution of the total transition probability between the initial
state and final state. The effect of a finite lifetime and a finite relaxation
time are also studied. We find that the oscillation pattern depends on the
magnitude of wave packet sizes of particles in the initial state and final
state and the lifetime of the initial particle. For $\Delta m^2_{21}=3\times
10^{-2}$ eV$^2$, the oscillation probability deviates from that of the standard
formula if the wave packet sizes are around $10^{-13}$ m for 0.4 MeV neutrino.


title: Localized Supersoft Supersymmetry Breaking

abstract:
  We consider supersymmetry breaking models in which the MSSM is extended to
include an additional chiral adjoint field for each gauge group with which the
the MSSM gauginos acquire Dirac masses. We investigate a framework in which the
Standard Model gauge fields propagate in the bulk of a warped extra dimension
while quarks and leptons are localized on the ultraviolet brane. The adjoint
fields are localized on the infrared brane, where supersymmetry is broken in a
hidden sector. This setup naturally suppresses potentially large flavor
violating effects, while allowing perturbative gauge coupling unification under
SU(5) to be realized. The Standard Model superpartner masses exhibit a
supersoft spectrum. Since the soft scalar masses are generated at very low
scales of order the gaugino masses these models are significantly less
fine-tuned than other supersymmetric models. The LSP in this class of models is
the gravitino, while the NLSP is the stau. We show that this theory has an
approximate R symmetry under which the gauginos are charged. This symmetry
allows several possibilities for experimentally distinguishing the Dirac nature
of the gauginos.


title:
Light Gluino Constituents of Hadrons and a Global Analysis of Hadron
  Scattering Data

abstract:
  Light strongly interacting supersymmetric particles may be treated as
partonic constituents of nucleons in high energy scattering processes. We
construct parton distribution functions for protons in which a light gluino is
included along with standard model quark, antiquark, and gluon constituents. A
global analysis is performed of a large set of data from deep-inelastic lepton
scattering, massive lepton pair and vector boson production, and hadron jet
production at large values of transverse momentum. Constraints are obtained on
the allowed range of gluino mass as a function of the value of the strong
coupling strength alpha_s(M_Z) determined at the scale of the Z boson mass. We
find that gluino masses as small as 10 GeV are admissible provided that
alpha_s(M_Z) \ge 0.12. Current hadron scattering data are insensitive to the
presence of gluinos heavier than ~ 100 - 150 GeV.


title: Dark Matter in the Finely Tuned Minimal Supersymmetric Standard Model

abstract:
  We explore dark matter in the Finely Tuned Minimal Supersymmetric Standard
model recently proposed by Arkani-Hamed and Dimopoulos. Relative to the MSSM,
there are fewer particles at freeze-out, so the calculation of the relic
abundance simplifies. Similarly, the predictions for direct detection of the
dark matter sharpen. There is a large region of mixed bino--higgsino dark
matter where the lightest supersymmetric particle will be accessible at both
the LHC and future direct detection experiments, allowing for a conclusive
identification of the dark matter particle. Typical dark matter-nucleon cross
sections are 10^{-45}-10^{-44} cm^{2}. This model also possesses a novel region
where the dark matter annihilates via an s-channel Higgs boson resonance.


title: Influence of tensor interactions on masses and decay widths of dibaryons

abstract:
  The influence of gluon and Goldstone boson induced tensor interactions on the
dibaryon masses and D-wave decay widths has been studied in the quark
delocalization, color screening model. The effective S-D wave transition
interactions induced by gluon and Goldstone boson exchanges decrease rapidly
with increasing strangeness of the channel. The tensor contribution of K and
$\eta$ mesons is negligible in this model. There is no six-quark state in the
light flavor world studied so far that can become bound by means of these
tensor interactions besides the deuteron. The partial D-wave decay widths of
the $IJ^p={1/2}2^+$ N$\Omega$ state to spin 0 and 1 $\Lambda\Xi$ final states
are 12.0 keV and 21.9 keV respectively. This is a very narrow dibaryon
resonance that might be detectable in relativistic heavy ion reactions by
existing RHIC detectors through the reconstruction of the vertex mass of the
decay product $\Lambda\Xi$ and by the COMPAS detector at CERN or at JHF in
Japan and the FAIR project in Germany in the future.


title: 511 KeV Photons From Color Superconducting Dark Matter

abstract:
  We discuss the possibility that the recent detection of 511 keV gamma rays
from the galactic bulge, as observed by INTEGRAL, can be naturally explained by
the supermassive very dense droplets (strangelets) of dark matter. These
droplets are assumed to be made of ordinary light quarks (or antiquarks)
condensed in non-hadronic color superconducting phase. The droplets can carry
electrons (or positrons) in the bulk or/and on the surface. The e^+e^-
annihilation events take place due to the collisions of electrons from the
visible matter with positrons from dark matter droplets which may result in the
bright 511 KeV gamma-ray line from the bulge of the Galaxy.


title: Cold Dark Matter and the LHC

abstract:
  The recent determination of the dark matter density in the Universe by the
WMAP satellite has brought new attention to the interplay of results from
particle physics experiments at accelerators and from cosmology. In this paper
we discuss the prospects for finding direct evidence for a candidate dark
matter particle at the LHC and the measurements which would be crucial for
testing its compatibility with cosmology data.


title: Fragmentation Production of Triply Heavy Baryons at the CERN LHC

abstract:
  The triply heavy baryons in the standard model formed in direct $c$ and $b$
quark fragmentation are the $\Omega_{ccc}$, $\Omega_{ccb}$, $\Omega_{cbb}$ and
$\Omega_{bbb}$ baryons. We calculate their fragmentation functions in leading
order of perturbative QCD. The universal fragmentation probabilities fall
within the range of $10^{-5}-10^{-7}$.We also evaluate their cross section at
the LHC ($\sqrt{s}=14$ TeV) using next-to-leading order matrix elements for
heavy quark-antiquark pair production. We present the differential cross
sections as functions of the transverse momentum as well as the total cross
sections. They range from a few nb to a few pb.


title:
Rotationally non-invariant aspects of scattering amplitudes with
  graviton exchange

abstract:
  We consider the s-channel scattering of massive fermion or vector-boson pairs
with equal helicities, mediated by a graviton in the linearized Einstein
theory. We show that, although in general both spin-2 and spin-0 components are
present in the exchanged graviton, there is a special set of reference frames
where the spin-0 graviton component vanishes. This is connected to the
dependence of the trace of the graviton propagator on the effective dimension
of the space-time spanned by the sources. On the other hand, one finds a
non-vanishing (Lorentz-invariant) interference of the graviton amplitude with
the scalar-exchange amplitude, that in principle could give measurable effects.


title: Saturation In Deep Inelastic Scattering

abstract:
  The solution to the BFKL equation grows like a power of center of mass
energy, s, violating unitarity conditions at high energies. The growth of the
cross section can be tamed by taking into account multiple pomeron exchanges.
This is known as saturation and it is expressed in the Balitsky-Kovchegov
equation. Conservation of energy should also slow down the growth of the cross
section, and our aim in this work is to study the effects of enforcing energy
conservation in DIS-events. Using the dipole picture, onium-onium collisions
can be viewed, in the large N_c and the leading logarithmic limits, as the
scattering of a collection of color dipoles. We construct a Monte Carlo
program, based on Mueller's model and using energy conservation, to study
onium-onium and onium-nucleus collisions. Dipole fusion processes will be
important at high gluon densities and should also slow down the growth of the
cross section. We propose an expression for the fusion factor and use it in our
Monte Carlo to study its effects.


title:
The size of chi = arg (-Vts Vtb* Vcs* Vcb) and physics beyond the
  Standard Model

abstract:
  We analyse the allowed range of values of chi, both in the Standard Model and
in models with New Physics, pointing out that a relatively large value of chi,
e.g. of order lambda, is only possible in models where the unitarity of the 3x3
Cabibbo-Kobayashi-Maskawa matrix is violated through the introduction of extra
Q=2/3 quarks. We study the interesting case where the extra quark is an
isosinglet, determining the allowed range for chi and the effect of a large chi
on various low-energy observables, such as CP asymmetries in B meson decays. We
also discuss the correlated effects which would be observable at high energy
colliders, like decays t -> cZ, modifications of the cross section and
forward-backward asymmetry in e+ e- -> ttbar and the direct production of a new
quark.


title: The Higgs Working Group: Summary Report 2003

abstract:
  Theoretical progress in Higgs boson production and background processes is
discussed with particular emphasis on QCD corrections at and beyond
next-to-leading order as well as next-to-leading order electroweak corrections.
The residual theoretical uncertainties of the investigated processes are
estimated in detail. Moreover, recent investigations of the MSSM Higgs sector
and other extensions of the SM Higgs sector are presented. The potential of the
LHC and a high-energy linear e+e- collider for the measurement of Higgs
couplings is analyzed.


title: The space-time structure of hard scattering processes

abstract:
  Recent studies of exclusive electroproduction of vector mesons at JLab make
it possible for the first time to play with two independent hard scales: the
virtuality Q^2 of the photon, which sets the observation scale, and the
momentum transfer t to the hadronic system, which sets the interaction scale.
They reinforce the description of hard scattering processes in terms of few
effective degrees of freedom relevant to the Jlab-Hermes energy range.


title: Sneutrino condensate as a candidate for the hot big bang cosmology

abstract:
  If inflationary paradigm is correct, then it must create conditions for the
hot big bang model with all observed matter, baryons and the seed perturbations
for the structure formation. In this paper we propose a scenario where the
inflaton energy density is dumped into the bulk in a brane world setup, and all
the required physical conditions are created by the right handed neutrino
sector within supersymmetry. The scalar component of the right handed Majorana
neutrino is responsible for generating the scale invariant fluctuations in the
cosmic microwave background radiation, reheating the Universe at a
temperature~$T_{rh}\leq 10^{9}$ GeV, and finally generating the lepton/baryon
asymmetry, $n_{B}/s\sim 10^{-10}$, with no lepton/baryon isocurvature
fluctuations.


title: $t\to cV$ via SUSY FCNC couplings in the unconstrained MSSM

abstract:
  We recalculate the branching ratios for $t\to cV$ ($V=g,\gamma,Z$) induced by
SUSY FCNC couplings within the general unconstrained MSSM framework using mass
eigenstate approach. Our results show that the branching ratios for these
decays are larger than ones reported in previous literatures in the MSSM with
R-parity conservation, and they can reach $\sim 10^{-4}$, $\sim 10^{-6}$, and
$\sim 10^{-6}$, respectively, for favorable parameter values allowed by current
precise experiments. Thus, the branching ratios for $t\to cg$ and $t\to
c\gamma$ may be measurable at the LHC.


title: The transverse momentum distribution of the Higgs boson at the LHC

abstract:
  We present perturbative predictions for the transverse momentum (q_T)
distribution of the Higgs boson at the LHC. At small q_T the
logarithmically-enhanced terms are resummed to all orders up to
next-to-next-to-leading logarithmic accuracy. The resummed component is
consistently matched to the next-to-leading order calculation valid at large
q_T. The results, which implement the most advanced perturbative information
that is available at present for this observable, show a good stability with
respect to perturbative QCD uncertainties.


title:
Heavy Quark Hadroproduction in $k_T$-Factorization Approach with
  Unintegrated Gluon Distributions

abstract:
  We consider the processes of compare the heavy quark production using the
unintegrated gluon distributions. The numerical predictions for high energy
nucleon-nucleon and photon-nucleon collisions of the $k_T$-factorization
approach (semihard theory) are compared with the experimental data from
Tevatron-collider and HERA. The total production cross sections and $p_T$
distributions are considered and they are in reasonable agreement with the data
for rather value of QCD scale.


title: Baryon Number Transfer in High Energy $hp$ Collisions

abstract:
  The process of baryon number transfer due to string junction propagation in
rapidity is considered. It has a significant effect in the net baryon
production in $pp$ collisions at mid-rapidities and an even larger effect in
the forward hemisphere in the cases of $\pi p$ and $\gamma p$ interactions. The
results of numerical calculations in the framework of the Quark-Gluon String
Model are in reasonable agreement with the data with the same parameter values
for different energies.


title: Thermodynamics of two-colour QCD and the Nambu Jona-Lasinio model

abstract:
  We investigate two-flavour and two-colour QCD at finite temperature and
chemical potential in comparison with a corresponding Nambu and Jona-Lasinio
model. By minimizing the thermodynamic potential of the system, we confirm that
a second order phase transition occurs at a value of the chemical potential
equal to half the mass of the chiral Goldstone mode. For chemical potentials
beyond this value the scalar diquarks undergo Bose condensation and the diquark
condensate is nonzero. We evaluate the behaviour of the chiral condensate, the
diquark condensate, the baryon charge density and the masses of scalar diquark,
antidiquark and pion, as functions of the chemical potential. Very good
agreement is found with lattice QCD (N_c=2) results. We also compare with a
model based on leading-order chiral effective field theory.


title: Analytic treatment of the two loop equal mass sunrise graph

abstract:
  The two loop equal mass sunrise graph is considered in the continuous
d-dimensional regularisation for arbitrary values of the momentum transfer.
After recalling the equivalence of the expansions at d=2 and d=4, the second
order differential equation for the scalar Master Integral is expanded in (d-2)
and solved by the variation of the constants method of Euler up to first order
in (d-2) included. That requires the knowledge of the two independent solutions
of the associated homogeneous equation, which are found to be related to the
complete elliptic integrals of the first kind of suitable arguments. The
behaviour and expansions of all the solutions at all the singular points of the
equation are exhaustively discussed and written down explicitly.


title: Genericity of Cosmic Strings Formation in SUSY GUTs

abstract:
  The idea of GUT implies that the universe went through a series of phase
transitions during which topological defects are expected to form. We
investigate here the genericity of cosmic strings formation in realistic SUSY
GUTs models. We conclude that all acceptable symmetry breaking schemes produce
cosmic strings after the last inflationary phase. Generically, as they form at
the end of inflation, they have a mass of order of the GUT scale. Since
cosmological data coming from CMB measurements do not show evidence for such
strings, they constrain GUT scale physics.


title: The Riddle of Polarization in $B \to VV$ Transitions

abstract:
  Measurements of polarization fractions in $B \to VV$ transitions, with $V$ a
light vector meson, show that the longitudinal amplitude dominates in $B^0 \to
\rho^+ \rho^-$, $B^+ \to \rho^+ \rho^0$, and $B^+ \to \rho^0 K^{*+}$ decays and
not in the penguin induced decays $B^0 \to \phi K^{*0}$, $B^+ \to \phi K^{*+}$.
We study the effect of rescattering mediated by charmed resonances, finding
that in $B \to \phi K^*$ it can be responsible of the suppression of the
longitudinal amplitude. For the decay $B \to \rho K^*$ we find that the
longitudinal fraction cannot be too large without invoking new effects.


title: Three-loop Phi-derivable Approximation in QED

abstract:
  In this paper we examine Phi-derivable approximations in QED. General
theorems tell us that the gauge dependence of the n-loop Phi-derivable
approximation shows up at order g^(2n) where g is the coupling constant. We
consider the gauge dependence of the two-loop Phi-derivable approximation to
the Debye mass and show that it is of order e^4 as expected. We solve the
three-loop Phi-derivable approximation in QED by expanding sum-integrals in
powers of e^2 and m/T, where m is the Debye mass which satisfies a variational
gap equation. The results for the pressure and the Debye mass are accurate to
order e^5.


title: Constraining SUSY GUTS with Cosmology

abstract:
  Cosmic strings of the GUT scale, generically formed during the SSB of
supersymmetric hybrid inflation, are compatible with the most recent CMB data.
The strong constraints on the allowed cosmic strings contribution to the
measured temperature anisotropies impose limits on the free parameters of the
inflationary models, namely the mass scales and the couplings.


title: Variational techniques in non-perturbative QCD

abstract:
  We review attempts to apply the variational principle to understand the
vacuum of non-abelian gauge theories. In particular, we focus on the method
explored by Ian Kogan and collaborators, which imposes exact gauge invariance
on the trial Gaussian wave functional prior to the minimization of energy. We
describe the application of the method to a toy model -- confining compact QED
in 2+1 dimensions -- where it works wonderfully and reproduces all known
non-trivial results. We then follow its applications to pure Yang-Mills theory
in 3+1 dimensions at zero and finite temperature. Among the results of the
variational calculation are dynamical mass generation and the analytic
description of the deconfinement phase transition.


title: Precise determination of the neutral Higgs boson masses in the MSSM

abstract:
  We present the implementation of the radiative corrections of the Higgs
sector in three public computer codes for the evaluation of the particle
spectrum in the Minimal Supersymmetric Standard Model, Softsusy, Spheno and
SuSpect. We incorporate the full one-loop corrections to the Higgs boson masses
and the electroweak symmetry breaking conditions, as well as the two-loop
corrections controlled by the strong gauge coupling and the Yukawa couplings of
the third generation fermions. We include also the corrections controlled by
the tau Yukawa coupling that we derived for completeness. The computation is
consistently performed in the DRbar renormalisation scheme. In a selected
number of MSSM scenarios, we study the effect of these corrections and analyse
the impact of some higher order effects. By considering the renormalisation
scheme and scale dependence, and the effect of the approximation of zero
external momentum in the two-loop corrections, we estimate the theoretical
uncertainty on the lighter Higgs boson mass to be 3 to 5 GeV. The uncertainty
on Mh due to the experimental error in the measurement of the SM input
parameters is approximately of the same size. Finally, we discuss the
phenomenological consequences, using the latest value of the top quark mass. We
find, in particular, that the most conservative upper bound on the lighter
Higgs boson mass in the general MSSM is Mh < 152 GeV and that there is no lower
bound on the parameter tan(beta) from non-observation of the MSSM Higgs bosons
at LEP2.


title: A Supersymmetric Stueckelberg U(1) Extension of the MSSM

abstract:
  A Stueckelberg extension of the MSSM with only one abelian vector and one
chiral superfield as an alternative to an abelian extension with Higgs scalars
is presented. The bosonic sector contains a new gauge boson Z' which is a sharp
resonance, and a new CP-even scalar, which combines with the MSSM Higgs bosons
to produce three neutral CP-even massive states. The neutral fermionic sector
has two additional fermions which mix with the four MSSM neutralinos to produce
an extended 6x6 neutralino mass matrix. For the case when the LSP is composed
mostly of the Stueckelberg fermions, the LSP of the MSSM will be unstable,
which leads to exotic decays of sparticles with many leptons in final states.
Prospects for supersymmetry searches and for dark matter are discussed.


title: Neutrino masses and R-parity violation

abstract:
  We review different contributions to the neutrino masses in the context of
R-parity violating supersymmetry in a basis independent manner. We comment on
the generic spectrum expected in such a scenario comparing different
contributions.


title:
Random walks of partons in SU(N_c) and classical representations of
  color charges in QCD at small x

abstract:
  The effective action for wee partons in large nuclei includes a sum over
static color sources distributed in a wide range of representations of the
SU(N_c) color group. The problem can be formulated as a random walk of partons
in the N_c-1 dimensional space spanned by the Casimirs of SU(N_c). For a large
number of sources, k >> 1, we show explicitly that the most likely
representation is a classical representation of order O(\sqrt{k}). The quantum
sum over representations is well approximated by a path integral over classical
sources with an exponential weight whose argument is the quadratic Casimir
operator of the group. The contributions of the higher N_c-2 Casimir operators
are suppressed by powers of k. Other applications of the techniques developed
here are discussed briefly.


title:
Hierarchical radiative masses in a supersymmetric three-family model
  without Higgsinos

abstract:
  We study the scalar potential and the mass spectrum of the supersymmetric
extension of a three-family model based on the local gauge group
$SU(3)_C\otimes SU(3)_L\otimes U(1)_X$, with anomalies canceled among the three
families in a nontrivial fashion. In this model the slepton multiplets play the
role of the Higgs scalars and no Higgsinos are needed, with the consequence
that the sneutrino, the selectron and six other sleptons play the role of the
Goldstone bosons of the theory. By introducing an Abelian anomaly-free discrete
symmetry and aligning the vacuum in a convenient way, we get a consistent mass
spectrum for the scalars and for the spin 1/2 quarks and charged leptons, where
only the top and charm quarks and the tau lepton acquire tree level masses
while the remaining ordinary charged fermions acquire radiative hierarchical
masses.


title:
Sivers function in light-cone quark model and azimuthal spin asymmetries
  in pion electroproduction

abstract:
  We perform a calculation of Sivers function in a light-cone SU(6)
quark-diquark model with both scalar diquark and vector diquark spectators. We
derive the transverse momentum dependent light-cone wave function of the proton
by taking into account the Melosh-Wigner rotation. By adopting one-gluon
exchange, we obtain a non-vanishing Sivers function of $down$ quark from
interference of proton spin amplitudes. We analyze the $\frac{|P_{h\perp}|}{M}$
weighted Sivers asymmetries in $\pi^+$, $\pi^-$ and $\pi^0$ electroproduction
off transverse polarized proton target, averaged and not averaged by the
kinematics of HERMES experiment.


title:
Compton and double Compton scattering processes at colliding
  electron-photon beams

abstract:
  Radiative corrections (RC) to the Compton scattering cross section are
calculated in the leading and next-to leading logarithmic approximation to the
case of colliding high energy photon-electron beams.
  RC to the double Compton scattering cross section in the same experimental
set-up are calculated in the leading logarithmic approximation.
  We consider the case when no pairs are created in the final state. We show
that the differential cross section can be written in the form of the Drell-Yan
process cross-section.
  Numerical values of the $K$-factor and the leading order distribution on the
scattered electron energy fraction and scattering angle are presented.


abstract:
  In soliton models expressed in terms of the non-linear chiral field, the
electric current has an anomalous gauge-field contribution as the baryon
current does. We study the spin polarized Skyrmions coupled with the
electromagnetic field via the gauged Wess-Zumino term and calculate
configurations of the Skyrmion and the gauge field with boundary conditions to
ensure the physical charge number for baryons.
  Although the electromagnetic field via the gauged Wess-Zumino term affects
physical quantities in small amounts, we find that the magnetic field forms a
dipole structure owing to a circular electric current around the spin
quantization axis of the soliton. This is understood on an analogy with the
Meissner effect in the super conductor.The electric charge distributions turn
out to have characteristic structures depending on the total charge, which
suggests the intrinsic deformation of baryons due to orbital motions of the
constituents.


title: Status of particle physics solutions to the UHECR puzzle

abstract:
  The status of solutions to the ultra-high energy cosmic ray puzzle that
involve particle physics beyond the standard model is reviewed. Signatures and
experimental constraints are discussed for most proposals like the Z burst
model and topological defects (both allowed only as subdominant contribution),
supermassive dark matter (no positive evidence from its key signatures galactic
anisotropy and photon dominance), strongly interacting neutrinos or new
primaries (no viable models known), and violation of Lorentz invariance
(possible).


title:
Spin Dependence of Heavy Quarkonium Production and Annihilation Rates:
  Complete Next-to-Next-to-Leading Logarithmic result

abstract:
  The ratio of the photon mediated production or annihilation rates of spin
triplet and spin singlet heavy quarkonium states is computed to the
next-to-next-to-leading logarithmic accuracy within the nonrelativistic
renormalization group approach. The result is presented in analytical form and
applied to the phenomenology of $t\bar{t}$, $b\bar{b}$ and $c\bar{c}$ systems.
The use of the nonrelativistic renormalization group considerably improves the
behaviour of the perturbative expansion and is crucial for accurate theoretical
analysis. For bottomonium decays we predict $\Gamma(\eta_b(1S) \to
\gamma\gamma)=0.659\pm 0.089 ({\rm th.}) {}^{+0.019}_{-0.018} (\delta
\alpha_{\rm s})\pm 0.015 ({\rm exp.}) {\rm keV}$. Our results question the
accuracy of the existing extractions of the strong coupling constant from the
bottomonium annihilation. As a by-product we obtain novel corrections to the
ratio of the ortho- and parapositronium decay rates: the corrections of order
$\alpha^4\ln^2\alpha$ and $\alpha^5\ln^3\alpha$.


title: Spin Effects in the Electron Structure Functions

abstract:
  The electron structure functions are studied in polarized $e^+e^-$
scattering. The formulae for longitudinally and transversely polarized
electrons are presented. The smallnes of the electron mass leads to negligible
cross-sections and asymmetries in some cases. Positivity constraints on the
structure functions and parton densities are constructed and discussed. The
cross-section asymmetries at very high energies, where the inclusion of all
elecroweak bosons is necessary, are calculated. Numerical examples, using the
asymptotic solutions for the parton densities inside the electron, are
presented.


title:
A New Method for the Determination of the Real Part of the Hadron
  Elastic Scattering Amplitude at Small Angles and High Energies

abstract:
  A new method for the determination of the real part of the elastic scattering
amplitude is examined for high energy proton-proton elastic scattering at small
momentum transfer. This method allows us to decrease the number of model
assumptions, to obtain the real part in a narrow region of momentum transfer
and to test different models. The real part is computed at a given point t_min
near t=0 from the known Coulomb amplitude. Hence one obtains an important
constraint on the real part of the forward scattering amplitude and therefore
on the rho-parameter (measuring the ratio of the real to imaginary part of the
scattering amplitude at t=0), which can be tested at LHC.


title: Higgs boson decays in the littlest Higss model

abstract:
  We calculate the two body Higgs boson decays in the framework of the littlest
Higgs model. The decay $H \to \gamma Z$ is computed at one loop level and,
using previous results, we evaluate the branching fractions in the framework of
the littlest Higgs model. A wide range of the space parameter of the model is
considered and possible deviations from the standard model are explored.


title: Charged Higgs production with a top quark at the LHC

abstract:
  I discuss charged Higgs production via the process bg -> t H- at the LHC. I
show that the cross section is dominated by soft-gluon corrections and I
provide results for its dependence on the charged Higgs mass and on the scale,
including higher-order effects.


title: Synergy of combined LHC and LC Analyses in Susy Searches

abstract:
  We present a case study for the synergy of combined LHC and LC analyses in
Susy searches where simultaneous running of both machines is very important. In
case that only light non-coloured Susy particles are accessible at a Linear
Collider with an initial energy of $\sqrt{s}=500$ GeV, the precise analysis at
the LC nevertheless leads to an accurate Susy parameter determination. This
allows the prediction of heavy Susy particles. Providing these LC results as
input for LHC analyses could be crucial for the identification of signals
resulting in a direct measurement of the heavy neutralinos. These results
provide an important consistency test of the underlying model. Furthermore,
feeding back the LHC results into LC analyses leads to an improvement in the
parameter determination.


title:
On the determination of the structure of the scalar Higgs boson's
  couplings to vectorbosons

abstract:
  In this paper we investigate the determination of the coupling structure of a
Higgs boson at the LHC using angular correlations in the decay chain H -> ZZ ->
4l. We consider the most general couplings of a scalar to spin 1 particles and
compare the angular correlations of the decay products using a maximum
likelihood method. We use the full information from the LO matrix element
including all posible correlations between the decay angles. In our analysis we
include all possible mixings between the different coupling structures. We
conclude that the coupling structure can in general be determined using this
approach. But it has to be noted, that for Higgs boson masses below the
ZZ-threshold the analysis is statistically limited. For higher Higgs boson
masses reasonably strong limits on non standard couplings can be achieved at
the LHC using the full integrated luminosity of 300 fb^-1.


title: Analysis of Neutrino oscillation data with the recent KamLAND results

abstract:
  We present an updated analysis of all available solar and reactor neutrino
data, emphasizing in particular the totality of the KamLAND results and
including the SNO phase III spectrum data.
  In a two active-neutrino framework, we determine the solutions in the $\Delta
m_{\odot}^2, \tan^2\theta_{\odot}$ parameter space compatible with experimental
data.
  Combining all data, we obtain the following best-fit parameters: $\Delta
m_{\odot}^2 =8.17*10^-5$, $\tan^2\theta_{\odot}=0.40$


title:
Cabibbo-suppressed decays of the Omega_c^0 - feedback to the Xi_c^+
  lifetime

abstract:
  We investigate a possible background of the type Omega_c^0 --> Xi_c^+ pi^- to
the CLEO Xi_c^+ lifetime measurement. This decay mode may lead to an
overestimate of the Xi_c^+ decay length and, therefore, increase the measured
Xi_c^+ lifetime. The branching ratio Gamma(Omega_c^0 --> Xi_c^+
pi^-)/Gamma(Omega_c^0 --> Omega^- pi^+) is analyzed in the framework of the
pole model and the modified current algebra. We find that the Omega_c^0 -->
Xi_c^+ pi^- decay mode could not generate a substantial systematic error in the
Xi_c^+ lifetime measurement. Also, it cannot significantly reduce the
disagreement between theoretical and experimental values of the Xi_c^+
lifetime.


title:
CP Violation and the CKM Matrix: Assessing the Impact of the Asymmetric
  B Factories

abstract:
  We update the profile of the CKM matrix. The apex (rhobar,etabar) of the
Unitarity Triangle is given by means of a global fit. We propose to include
therein sin2alpha from the CP-violating asymmetries in B0->rho+rho-, using
isospin to discriminate the penguin contribution. The constraint from
epsilon'/epsilon is briefly discussed. We study the impact from the measurement
of the rare decay K+->pi+nunu-bar, and from a future observation of
KL->pi0nunubar. The B system is investigated in detail, beginning with
2beta+gamma and gamma from B0->D(*)+-pi-+ and B+->D(*)0K+. A significant part
of this paper is dedicated to B decays into pipi, Kpi, rhopi and rhorho.
Various phenomenological and theoretical approaches are studied. Within QCD
Factorization we find a remarkable agreement of the pipi and Kpi data with the
other UT constraints. A fit of QCD FA to all pipi and Kpi data leads to precise
predictions of the related observables. We analyze separately the B->Kpi
decays, and in particular the impact of electroweak penguins in response to
recent phenomenological discussions. We find no significant constraint on
electroweak nor hadronic parameters. We do not observe any unambiguous sign of
New Physics, whereas there is some evidence for potentially large rescattering
effects. Finally we use a model-independent description of a large class of New
Physics effects in both BBbar mixing and B decays, namely in the b->d and b->s
gluonic penguin amplitudes, to perform a new numerical analysis. Significant
non-standard corrections cannot be excluded yet, however standard solutions are
favored in most cases.


title:
On the scalar product of short and long living states of neutral kaons
  in the CPT invariant system

abstract:
  This paper contains a detailed analysis of the properties of the scalar
product of short and long living superpositions of neutral $|K_{0}>$,
$|{\bar{K}}_{0}>$ mesons. It is shown for the exact effective Hamiltonian for
neutral meson subsystem that the scalar product of its eigenvectors, which
correspond with these short and long living superpositions, can not be real
with the assumption of CPT conserved and CP violated. The standard conclusion
obtained within the Lee-Oehme-Yang theory of neutral kaons is that in this case
such a product should be real.


title: Lorentz Contraction of Bound States in 1+1 Dimensional Gauge Theory

abstract:
  We consider the Lorentz contraction of a fermion-antifermion bound state in
1+1 dimensional QED. In 1+1 dimensions the absence of physical, propagating
photons allows us to explicitly solve the weak coupling limit \alpha << m^2 of
the Bethe-Salpeter bound state equation in any Lorentz frame. In a time-ordered
formalism it is seen that all pair production is suppressed in this limit. The
wave function is shown to contract while the mass spectrum is invariant under
boosts.


title:
Charge symmetry breaking in pion-nucleon coupling constant : QCD sum
  rule approach

abstract:
  Using the vacuum-to-pion matrix element of the correlation function of the
interpolating fields of the two nucleons, the isospin splitting in the diagonal
pion-nucleon coupling constant has been studied in the framework of the
conventional QCD sum rule. Some of the implications of this splitting has also
been discussed.


title: Collective modes of an Anisotropic Quark-Gluon Plasma II

abstract:
  We continue our exploration of the collective modes of an anisotropic quark
gluon plasma by extending our previous analysis to arbitrary Riemann sheets. We
demonstrate that in the presence of momentum-space anisotropies in the parton
distribution functions there are new relevant singularities on the neighboring
unphysical sheets. We then show that for sufficiently strong anisotropies that
these singularities move into the region of spacelike momentum and their effect
can extend down to the physical sheet. In order to demonstrate this explicitly
we consider the polarization tensor for gluons propagating parallel to the
anisotropy direction. We derive analytic expressions for the gluon structure
functions in this case and then analytically continue them to unphysical
Riemann sheets. Using the resulting analytic continuations we numerically
determine the position of the unphysical singularities. We then show that in
the limit of infinite contraction of the distribution function along the
anisotropy direction that the unphysical singularities move onto the physical
sheet and result in real spacelike modes at large momenta for all
"out-of-plane" angles of propagation.


title: Constrained Molecular Dynamics simulation of the Quark-Gluon Plasma

abstract:
  We calculate the Equation of State of a quark system interacting through a
phenomenological potential: the Richardson's potential, at finite baryon
density and zero temperature. In particular we study three different cases with
different quark masses($u$ and $d$), and different assumptions for the
potential at large distances. We solve molecular dynamics with a constraint due
to Pauli blocking and find evidencies of a phase transition from "nuclear" to
"quark matter", which is analyzed also through the behaviour of the $J/\Psi$
embedded in the quark system. We show that the $J/\Psi$ particle behaves as an
order parameter.


title: A T-odd asymmetry in neutralino production and decay

abstract:
  We study CP-violating effects in neutralino production and subsequent decay
within the Minimal Supersymmetric Standard Model with complex parameters M_1
and mu. The observable we propose is a T-odd asymmetry based on a triple
product in neutralino production e^+ e^- -> tilde{chi}^0_i tilde{chi}^0_2, i =
1,...,4, with subsequent leptonic three-body decay tilde{chi}^0_2 ->
tilde{chi}^0_1 l^+ l^-, l = e, mu, at an e^+ e^- linear collider with sqrt{s} =
500 GeV and polarised beams. We provide compact analytical formulae for the
cross section and the T-odd asymmetry taking into account the complete spin
correlations between production and decay. We give numerical predictions for
the cross section and the T-odd asymmetry. The asymmetry can go up to 10 %.


title: The Paradigm of Inflation

abstract:
  The standard model of cosmology is based on the hot Big Bang theory and the
inflationary paradigm. Recent precise observations of the temperature and
polarization anisotropies in the cosmic microwave background and the matter
distribution in large scale structures like galaxies and clusters confirm the
general paradigm and put severe constrains on variations of this simple idea.
In this essay I will discuss the epistemological foundations of such a paradigm
and speculate on its possible realisation within a more fundamental theory.


title: Methods for Measuring New-Physics Parameters in B Decays

abstract:
  Recently, it was argued that new-physics (NP) effects in B decays can be
approximately parametrized in terms of a few quantities. As a result, CP
violation in the $B$ system allows one not only to detect the presence of new
physics (NP), but also to measure its parameters. This will allow a partial
identification of the NP, before its production at high-energy colliders. In
this paper, we examine three methods for measuring NP parameters. The first
uses a technique involving both $\btos$ and $\btod$ penguin B decays. Depending
on which pair of decays is used, the theoretical error is in the range 5--15%.
The second involves a comparison of $B\to \pi K$ and $B\to\pi\pi$ decays.
Although the theoretical error is large ($\gsim 25%$), the method can be
performed now, with presently-available data. The third is via a time-dependent
angular analysis of $\bvv$ decays. In this case, there is no theoretical error,
but the technique is experimentally challenging, and the method applies only to
those NP models whose weak phase is universal to all NP operators. A reliable
identification of the NP will involve the measurement of the NP parameters in
many different ways, and with as many B decay modes as possible, so that it
will be important to use all of these methods.


title: Solution of the Fan Diagram Equation in 2+1 Dimensional QCD

abstract:
  We investigate the Balitsky-Kovchegov (BK) equation for D=3 space-time
dimensions, corresponding to one transverse coordinate, and we show that it can
be solved analytically. The explicit solutions are found in the linear
approximation and for the paricular cases when they do not depend on the impact
parameter of the dipole or on its rapidity. It is shown, that in a general case
different solutions are related by an infinite parameter group of
transformations. The key observation is that the equation has the
Kowalewskaya-Painlev\'{e} property, which gives the possibility of reducing the
non-linear problem to the solution of a linear integral equation.


title: Gauged Nambu-Jona-Lasinio model with extra dimensions

abstract:
  We investigate phase structure of the D (> 4)-dimensional gauged
Nambu-Jona-Lasinio (NJL) model with $\delta(=D-4)$ extra dimensions
compactified on TeV scale, based on the improved ladder Schwinger-Dyson (SD)
equation in the bulk. We assume that the bulk running gauge coupling in the SD
equation for the SU(N_c) gauge theory with N_f massless flavors is given by the
truncated Kaluza-Klein effective theory and hence has a nontrivial ultraviolet
fixed point (UVFP). We find the critical line in the parameter space of two
couplings, the gauge coupling and the four-fermion coupling, which is similar
to that of the gauged NJL model with fixed (walking) gauge coupling in four
dimensions. It is shown that in the presence of such walking gauge interactions
the four-fermion interactions become ``nontrivial'' even in higher dimensions,
similarly to the four-dimensional gauged NJL model. Such a nontriviality holds
only in the restricted region of the critical line (``nontrivial window'') with
the gauge coupling larger than a non-vanishing value (``marginal triviality
(MT)'' point), in contrast to the four-dimensional case where such a
nontriviality holds for all regions of the critical line except for the pure
NJL point. In the nontrivial window the renormalized effective potential yields
a nontrivial interaction which is conformal invariant. The exisitence of the
nontrivial window implies ``cutoff insensitivity'' of the physics prediction in
spite of the ultraviolet dominance of the dynamics. In the formal limit D -> 4,
the nontrivial window coincides with the known condition of the nontriviality
of the four-dimensional gauged NJL model, $9/(2N_c) < N_f - N_c < 9/2 N_c$.


title: A Model of Neutrino Masses and Mixing from Hierarchy and Symmetry

abstract:
  We construct a model that allows us to determine the three neutrino masses
directly from the experimental mass squared differences, $\Delta_{\rm atm}$ and
$\Delta_{\rm sol}$, together with the assumption that $\Lambda = \surd (1/6) =
\surd (m_2/m_3)$. The parameter, $\Lambda$, basically a Clebsch-Gordan
coefficient with the value of about 0.4 stems from the group $S_3$, and is NOT
an expansion parameter, in contrast with the Wolfenstein parameter, $0.22
<\lambda < 0.25$ needed to explain quark masses. For a variety of initial
values of $\Delta_{\rm atm}$, we find that the lowest mass, $m_1$, varies from
$1.4 - 3.6 10^{-3} eV$, the next lowest mass, $m_2$ varies only slightly from
$8.4 - 9.0 10^{-3} eV$, and the heaviest mass, $m_3$, ranges from $5.0 - 5.4
10^{-2} eV$. The elements of the mixing matrix, $U$, and of the mass matrix,
$M$, are examined with particular emphasis on the role of small angle
$\theta_{13}$. The phase, $\delta$, of the mixing matrix $U$ has a serious
effect in the mass matrix only for the matrix elements $M_{e\mu}$ and
$M_{e\tau}$, because these are the only ones for which the real part vanishes
in the allowed range for $\theta_{13}$. Their dependence on $s_{13}$ for
various values of $\delta$ is given explicitly. We study the elements of the
mass matrix, $M$, for our solution 1, that of the perfect rational hierarchy,
for the case $\delta = 0$, and find that all of them are smaller than $0.03
eV$. The only candidates for double texture zero models are $M_{ee}$ and
$M_{e\mu} = M_{\mu e}$.


title: A study of pentaquarks on the lattice with overlap fermions

abstract:
  We present a quenched lattice QCD calculation of spin-1/2 five-quark states
with $uudd\bar{s}$ quark content for both positive and negative parities. We do
not observe any bound pentaquark state in these channels for either I = 0 or I
=1. The states we found are consistent with KN scattering states which are
checked to exhibit the expected volume dependence of the spectral weight. The
results are based on overlap-fermion propagators on two lattices, 12^3 x 28 and
16^3 x 28, with the same lattice spacing of 0.2 fm, and pion mass as low as ~
180 MeV.


title: Naturalness and the Landscape

abstract: This paper was withdrawn by the author.


title: Pentaquark in a supersmmetric quark-diquark model

abstract:
  According to QCD, there exists a broken dynamical supersymmetry between an
antiquark and a diquark. This supersymmetry can be used to relate the mass of a
pentaquark to the mass of an antibaryon by replacing two antiquarks in an
antibaryon by two diquarks to form a pentaquark. Using this technique, we find
that the mass of an exotic pentaquark with strangeness plus 1 is greater than
1.74 GeV, or at least 200 MeV larger than that of the reported $\Theta^+$
pentaquark. Furthermore, there is no reason for the pentaquark to be narrow; on
the contrary, it is expected to be so broad that it will be difficult to
observe.


title: Neutrinoless Double Beta Decay and Lepton Flavor Violation

abstract:
  We point out that extensions of the Standard Model with low scale (~TeV)
lepton number violation (LNV) generally lead to a pattern of lepton flavor
violation (LFV) experimentally distinguishable from the one implied by models
with GUT scale LNV. As a consequence, muon LFV processes provide a powerful
diagnostic tool to determine whether or not the effective neutrino mass can be
deduced from the rate of neutrinoless double beta decay. We discuss the role of
\mu -> e \gamma and \mu -> e conversion in nuclei, which will be studied with
high sensitivity in forthcoming experiments.


title: Composite Higgs from Higher Representations

abstract:
  We investigate new models of dynamical electroweak symmetry breaking
resulting from the condensation of fermions in higher representations of the
technicolor group. These models lie close to the conformal window, and are free
from the flavor-changing neutral current problem despite small numbers of
flavors and colors. Their contribution to the S parameter is small and not
excluded by precision data. The Higgs itself can be light and narrow.


title: Leading-particle suppression in high energy nucleus-nucleus collisions

abstract:
  Parton energy loss effects in heavy-ion collisions are studied with the Monte
Carlo program PQM (Parton Quenching Model) constructed using the BDMPS
quenching weights and a realistic collision geometry. The merit of the approach
is that it contains only one free parameter that is tuned to the high-pt
nuclear modification factor measured in central Au-Au collisions at sqrt{s_NN}
= 200 GeV. Once tuned, the model is coherently applied to all the high-pt
observables at 200 GeV: the centrality evolution of the nuclear modification
factor, the suppression of the away-side jet-like correlations, and the
azimuthal anisotropies for these observables. Predictions for the
leading-particle suppression at nucleon-nucleon centre-of-mass energies of 62.4
and 5500 GeV are calculated. The limits of the eikonal approximation in the
BDMPS approach, when applied to finite-energy partons, are discussed.


title: Testing an Optimised Expansion on Z_2 Lattice Models

abstract:
  We test an optimised hopping parameter expansion on various Z_2 lattice
scalar field models: the Ising model, a spin-one model and lambda (phi)^4. We
do this by studying the critical indices for a variety of optimisation
criteria, in a range of dimensions and with various trial actions. We work up
to seventh order, thus going well beyond previous studies. We demonstrate how
to use numerical methods to generate the high order diagrams and their
corresponding expressions. These are then used to calculate results numerically
and, in the case of the Ising model, we obtain some analytic results. We
highlight problems with several optimisation schemes and show for the best
scheme that the critical exponents are consistent with mean field results to at
least 8 significant figures. We conclude that in its present form, such
optimised lattice expansions do not seem to be capturing the non-perturbative
infra-red physics near the critical points of scalar models.


title:
A complete set of scalar master integrals for massive 2-loop Bhabha
  scattering: where we are

abstract:
  We define a complete set of scalar master integrals (MIs) for massive 2-loop
QED Bhabha scattering. Among others, there are thirty three 2-loop box type
MIs. Five of them have been published in (semi-)analytical form, one is
determined here, the rest remains to be calculated. Further, the last four so
far unknown 2-loop 3-point MIs are identified and also computed here.


title: Pentaquarks

abstract:
  Since LEPS collaboration reported the first evidence of $\Theta^+$ pentaquark
in early 2003, eleven other experimental groups have confirmed this exotic
state while many other groups didn't see any signal. If this state is further
established by future high statistical experiments, its discovery shall be one
of the most important events in hadron physics for the past three decades. This
exotic baryon with such a low mass and so narrow a width imposes a big
challenge to hadron theorists. Up to now, there have appeared more than two
hundred theoretical papers trying to interpret this charming state. I will
review some important theoretical developments on pentaquarks based on my
biased personal views.


title: A note about the t`Hooft`s ansatz for SU(N) real time guage theories

abstract:
  The t`Hooft's ansatz reduces the classical Yang--Mills theory to the
$\lambda\phi^4$ one. It is shown that in the frame of this ansatz the real-time
classical solutions for the arbitrary SU(N) gauge group is obtained by
embedding $SU(2)\times SU(2)$ into SU(N). It is argued that this group
structure is the only possibility in the frame of the considered ansatz. New
explicit solutions for SU(3) and SU(5) gauge groups are shown.


title: Democratic Neutrino Mixing Reexamined

abstract:
  We reexamine the democratic neutrino mixing ansatz, in which the mass
matrices of charged leptons and Majorana neutrinos arise respectively from the
explicit breaking of S(3)_L x S(3)_R and S(3) flavor symmetries. It is shown
that a democracy term in the neutrino sector can naturally allow the ansatz to
fit the solar neutrino mixing angle \theta_sun \approx 33^\circ. We predict
\sin^2 2\theta_atm \approx 0.95 for atmospheric neutrino mixing and J \approx
1.2% for leptonic CP violation in neutrino oscillations without any
fine-tuning. Direct relations between the model parameters and experimental
observables are also discussed.


title:
Dimensional Reduction of ten-dimensional Supersymmetric Gauge Theories
  in the N=1, D=4 Superfield Formalism

abstract:
  A ten-dimensional supersymmetric gauge theory is written in terms of N=1, D=4
superfields. The theory is dimensionally reduced over six-dimensional coset
spaces. We find that the resulting four-dimensional theory is either a softly
broken N=1 supersymmetric gauge theory or a non-supersymmetric gauge theory
depending on whether the coset spaces used in the reduction are non-symmetric
or symmetric. In both cases examples susceptible to yield realistic models are
presented.


title:
The effects of non-universal extra dimensions on the radiative lepton
  flavor decays \mu\to e\gamma and \tau\to \mu\gamma in the two Higgs doublet
  model

abstract:
  We study the effect of non-universal extra dimensions on the branching ratios
of the lepton flavor violating processes \mu\to e\gamma and \tau\to \mu\gamma
in the general two Higgs doublet model. We observe that these effects are small
for a single extra dimension, however, in the case of two extra dimensions
there is a considerable enhancement in the additional contributions.


title: Virtual Photon Correction to the $K^+\to\pi^+\pi^0\pi^0$ Decay

abstract:
  We consider electromagnetic corrections to the non-leptonic kaon decay,
$K^+\to\pi^+\pi^0\pi^0$, due to explicit virtual photons only. The decay
amplitude is calculated at one-loop level in the framework of Chiral
Perturbation Theory. The interest in this process is twofold: It is actually
measured by the NA48 collaboration from one side, and, the value of the
amplitude at the $\pi\pi$ threshold gives access to $\pi\pi$ scattering lengths
from the other side. We found that the present correction is about 5 to 6% the
value of the Born amplitude squared. Combined with another piece published
recently, this fixes the size of isospin breaking correction to the amplitude
squared to 7% its one-loop level value in the absence of isospin breaking and
at the center of Dalitz plot.


title:
Mixed Quark-Gluon condensate at finite temperature and density in the
  global color symmetry model

abstract:
  The mixed quark-gluon condensate is another chiral order parameter in QCD,
which plays an important role in the application of QCD sum rules. In this
letter, we study the properties of quark-gluon mixed condensate at finite
temperature and quark chemical potential in the framework of global color
symmetry model. Using an infrared-dominant model gluon two-point function, we
find that the behavior of quark-gluon mixed condensate at finite temperature
and chemical potential is similar to that of the quark condensate, and both of
them give the same information about chiral phase transition. We also find that
the ratio of these two condensates is insensitive to the temperature and
chemical potential, which supports the conclusion obtained recently by the
authors using quenched lattice QCD (They only studied the nature of the mixed
quark-gluon condensate at finite temperature).


title: Theoretical Overview of the Pentaquark Baryons

abstract:
  A review is given of the theoretical ideas concerning the mysterious
pentaquark baryons proposed during the first year after its discovery. We focus
on the difficulties involved with the constituent quark models and the
discrepancy between the QCD predictions and most of the phenomenological
models.


title: Parton recombination effect in polarized parton distributions

abstract:
  Parton recombination corrections to the standard spin-dependent
Altarelli-Parisi evolution equation are considered in a nonlinear evolution
equation. The properties of this recombination equation and its relation with
the spin-averaged form are discussed.


title: Properties of the gluon recombination functions

abstract:
  The gluon recombination functions in the twist-4 QCD evolution equations are
studied at the leading logarithmic approximation using both the covariant and
non-covariant methods. We justify that the infrared singularities in the
twist-4 coefficient functions impede us to simply separate the QCD evolution
kernels from the coefficient functions at the equivalent particle
approximation. In particulary, we point out that the gluon recombination
functions in the GLR-MQ evolution equation are unavailable. The methods
avoiding the IR divergences are discussed, which can be used in the derivations
of the evolution kernels and coefficient functions at the higher twist level.


title: Supersymmetric Large Extra Dimensions

abstract:
  This article summarizes the proposal to address the cosmological constant
problem within the framework of supersymmetric large extra dimensions (SLED).
The proposed mechanism is described, emphasizing the relaxation mechanism which
ensures that low-energy particles like the electron do not contribute too large
a vacuum energy. This is followed by a preliminary discussion of outstanding
issues and observational consequences.


title:
NMHDECAY: A Fortran Code for the Higgs Masses, Couplings and Decay
  Widths in the NMSSM

abstract:
  The Fortran code NMHDECAY computes the masses, couplings and decay widths of
all Higgs bosons of the NMSSM in terms of its parameters at the electroweak
(SUSY breaking) scale: the Yukawa couplings lambda and kappa, the soft
trilinear terms A_lambda and A_kappa, and tan(beta) and mu_eff = lambda*<S>.
The computation of the spectrum includes leading two loop terms, electroweak
corrections and propagator corrections. The computation of the decay widths is
carried out as in HDECAY, but (for the moment) without three body decays. Each
point in parameter space is checked against negative Higgs bosons searches at
LEP, including unconventional channels relevant for the NMSSM. One version of
the program uses generalized SLHA conventions for input and output.


title: Auxiliary fields and the flux tube model

abstract:
  It is possible to eliminate exactly all the auxiliary fields (einbein fields)
appearing in the rotating string Hamiltonian to obtain the classical equations
of motion of the relativistic flux tube model. A clear interpretation can then
be done for the characteristic variables of the rotating string model.


title: Resummed pole mass, static potential, and Upsilon(1S) spectrum

abstract:
  Employing the heavy quark pole mass and static potential that were obtained
from resummation of the renormalon-caused large order behavior to all orders,
and matching the resummed static potential to the long distance Cornell
potential we obtain a new estimate of the bottom quark mass % $m_b^{\bar{\text
% MS}}=4.20$ GeV at $\alpha_s(M_z)=0.118$ from $\Upsilon$(1S) system. We point
out that the pure perturbative QCD approach to $\Upsilon$(1S) spectrum should
have a sizable systematic error of about 100 MeV, due to the absence of the
long distance confining potential, and that the incorporation of the latter is
essential for accurate determination of the ground state energy. We also
recalculate the nonperturbative Leutwyler-Voloshin effect using a resummed
octet potential matched to a confining linear potential, and obtain a result
that is substantially smaller than the estimates based on Coulombic potentials.
The hyperfine splitting is estimated to be $50 \pm 8$ MeV at
$\alpha_s(M_z)=0.118$.


title:
Nuclear spin structure in dark matter search: The zero momentum transfer
  limit

abstract:
  We review the calculation of spin-dependent matrix elements relevant to
scattering of weakly interacting massive particles on nuclei. A comprehensive
list, to our knowledge, of the proton and neutron total spin expectation values
($<{\bf S}_{p}>$ and $<{\bf S}_{n}>$) calculated within different nuclear
models is presented. These values allow a conclusion about the event rate
expected in direct dark matter search experiments due to spin-dependent
neutralino-nucleon interaction, provided neutralino is a dark matter particle.


title: Surprises in nonperturbative dynamics in sigma-model at finite density

abstract:
  The linear $SU(2)_L \times SU(2)_R$ sigma-model occupies a unique place in
elementary particle physics and quantum field theory. It has been recently
realized that when a chemical potential for hypercharge is added, it becomes a
toy model for the description of the dynamics of the kaon condensate in high
density QCD. We review recent results in nonperturbative dynamics obtained in
the ungauged and gauged versions of this model.


title: On the Paschos-Wolfenstein Relationship for Nuclei

abstract:
  Nuclear effects and QCD perturbative corrections to the Paschos-Wolfenstein
relationship are discussed. We argue that perturbative corrections largely
cancel out in this relationship for total cross sections while the neutron
excess correction in heavy nuclei is enhanced by Fermi motion and nuclear
binding effects. These observations are discussed in the context of NuTeV
measurement of the Weinberg mixing angle.


title: Fermion Masses and Flavor Mixing in A Supersymmetric SO(10) Model

abstract:
  we study fermion masses and flavor mixing in a supersymmetric SO(10) model,
where $\mathbf{10}$, $\mathbf{120}$ and $\mathbf{\bar{126}}$ Higgs multiplets
have Yukawa couplings with matter multiplets and give masses to quarks and
leptons through the breaking chain of a Pati-Salam group. This brings about
that, at the GUT energy scale, the lepton mass matrices are related to the
quark ones via several breaking parameters, and the small neutrino masses arise
from a Type II see-saw mechanism. When evolving renormalization group equations
for the fermion mass matrices from the GUT scale to the electroweak scale, in a
specific parameter scenario, we show that the model can elegantly accommodate
all observed values of masses and mixing for the quarks and leptons,
especially, it's predictions for the bi-large mixing in the leptonic sector are
very well in agreement with the current neutrino experimental data.


title:
Spin Asymmetries in Squark and Gluino Production at Polarized Hadron
  Colliders

abstract:
  We study the production cross sections for squarks and gluinos in collision
of longitudinally polarized hadrons. The corresponding polarized partonic cross
sections are computed in leading order supersymmetric QCD. The resulting
asymmetries are evaluated for the polarized proton collider RHIC, as well as
for hypothetical polarized options of the Tevatron and the LHC. These
asymmetries turn out to be sizable over a wide range of supersymmetric particle
masses, thus potentially opening a window to detailed sparticle spectroscopy at
future polarized hadron colliders.


title:
Unintegrated parton distributions and meson production in hadronic
  collisions

abstract:
  The inclusive distributions of gluons and pions for high-energy NN collisions
are calculated. The results for several unintegrated gluon distributions
(UGD's) from the literature are compared. We find huge differences in both
rapidity and $p_t$ of gluons and $\pi$'s in NN collisions for different models
of UGD's. The Karzeev-Levin UGD gives good description of momentum distribution
of charged hadrons at midrapidities. We find, however, that the gluonic
mechanism discussed does not describe the inclusive distributions of charged
particles in the fragmentation region. Some of the missing mechanisms are
calculated with the help of unintegrated parton distributions being solutions
of the Kwieci\'nski CCFM equations. We predict an asymmetry in $\pi^+$ and
$\pi^-$ production which could be studied by the BRAHMS collaboration at RHIC.


title: A QCD analysis of diffractive deep-inelastic scattering data

abstract:
  We perform a novel type of analysis of diffractive deep-inelastic scattering
data, in which the input parton distributions of the Pomeron are parameterised
using the perturbative QCD expressions. In particular, we treat individually
the components of the Pomeron of different size. We are able to describe
simultaneously both the recent ZEUS and H1 diffractive data. In addition to the
usual two-gluon model for the perturbative Pomeron, we allow for the
possibility that it may be made from two sea quarks.


title: Simultaneous QCD analysis of diffractive and inclusive DIS data

abstract:
  We perform a NLO QCD analysis of deep-inelastic scattering data, in which we
account for absorptive corrections. These corrections are determined from a
simultaneous analysis of diffractive deep-inelastic data. The absorptive
effects are found to enhance the size of the gluon distribution at small x,
such that a negative input gluon distribution at Q^2 = 1 GeV^2 is no longer
required. We discuss the problem that the gluon distribution is valence-like at
low scales, whereas the sea quark distribution grows with decreasing x. Our
study hints at the possible importance of power corrections for Q^2 \simeq 1--2
GeV^2.


title: Strange sea asymmetry from global QCD fits

abstract:
  We present a preliminary account of a new global QCD analysis of DIS data,
including recent $\nu, \bar \nu$ DIS measurements. The model-independent cross
section reanalysis by CCFR allows a new determination of the strange sea
asymmetry, whose first moment is found to be small. The impact on the NuTeV
measurement of $\sin^2 \theta_W$ is discussed.


title: SNO, SuperKamiokande data, antineutrinos and sterile neutrinos

abstract:
  Allowing for antineutrinos ($\bar\nu_x$) and sterile neutrinos ($\nu_s$) to
accompany LMA oscillations, we derive in a model independent way, upper bounds
on their components in the solar flux, using the recent data from SNO and
SuperKamiokande. Along with the general case (LMA + $\bar\nu_x$ + $\nu_s$) we
consider the special cases where only $\bar\nu_x$ or $\nu_s$ are present. We
obtain an upper bound on $\bar\nu_x$ which is independent of the $\nu_s$
component. In the no sterile case we obtain upper and lower bounds on $f_B$,
the SSM normalization factor. We also investigate in the general case the
common parameter range for $f_B$ and the $\bar\nu_x$, $\nu_s$ components and
find that the upper bound on $\nu_s$ is hardly sensitive to the $\bar\nu_x$
component. In the absence of $\bar\nu_x$ we recover the $\nu_s$ upper bound
existing in the literature. We finally present a simple $\chi^2$ analysis of
all four cases considered.


title: Spectroscopy of B_c Mesons in the Relativized Quark Model

abstract:
  We calculate the spectrum of the charm-beauty mesons using the relativized
quark model. Using the wavefunctions from this model we compute the radiative
widths of excited c\bar{b} states. The hadronic transition rates between
c\bar{b} states are estimated using the Kuang-Yan approach and are combined
with the radiative widths to give estimates of the relative branching ratios.
These results are combined with production rates at the Tevatron and the LHC to
suggest promising signals for excited B_c states. Our results are compared with
other models to gauge the reliability of the predictions and point out
differences.


title: Study of Higgs Boson Pair Production at Linear Collider

abstract:
  We study the potential of the TESLA linear collider operated at a
center-of-mass energy of 500 to 1000 GeV for the measurement of the neutral
Higgs boson properties within the framework of the MSSM. The process of
associated Higgs boson production with subsequent decays of Higgs bosons into
b-quark and tau-lepton pairs is considered. An integrated luminosity of 500
fb^{-1} is assumed at each energy. The Higgs boson masses and production cross
sections are measured by reconstructing the bbbb and bb\tau\tau final states.
The precision of these measurements is evaluated in dependence of the Higgs
boson masses. Under the assumed experimental conditions a statistical accuracy
ranging from 0.1 to 1.0 GeV is achievable on the Higgs boson mass. The
topological cross section \sigma(e+e- -> HA -> bbbb) can be determined with the
relative precision of 1.5 - 6.6 % and cross sections \sigma(e+e- -> HA -> bb
\tau\tau) and \sigma(e+e- -> HA -> \tau\tau bb) with precision of 4 - 30 %.
Constraints on the Higgs boson widths can be set exploiting bb\tau\tau channel.
The 5\sigma discovery limit corresponds to the Higgs mass of around 385 GeV for
the degenerate Higgs boson masses in the HA -> bbbb channel at \sqrts = 800 GeV
with integrated luminosity of 500 fb^{-1}. The potential of the Higgs mass
determination for the benchmark point SPS 1a for the process e+e- -> HA -> bbbb
at \sqrt{s} = 1 TeV and luminosity 1000 fb^{-1} is investigated.


title:
A phenomenological analysis of the longitudinal structure function at
  small $x$ and low $Q^2$

abstract:
  The longitudinal structure function in deep inelastic scattering is one of
the observables from which the gluon distribution can be unfolded.
Consequently, this observable can be used to constrain the QCD dynamics at
small $x$. In this work we compare the predictions of distinct QCD models with
the recent experimental results for $F_L(x,Q^2)$ at small $x$ and low $Q^2$
obtained by the H1 collaboration. We focus mainly on the color dipole approach,
selecting those models which include saturation effects. Such models are
suitable at this kinematical region and also resum a wide class of higher twist
contributions to the observables. Therefore, we investigate the influence of
these corrections to $F_L$ in the present region of interest.


title:
Stability of the tree-level vacuum in two Higgs doublet models against
  charge or CP spontaneous violation

abstract:
  We show that in two Higgs doublet models at tree-level the potential minimum
preserving electric charge and CP symmetries, when it exists, is the global
one. Furthermore, we derived a very simple condition, involving only the
coefficients of the quartic terms of the potential, that guarantees spontaneous
CP breaking.


title: New Results on B->pi, K, eta Decay Formfactors from Light-Cone Sum Rules

abstract:
  We present an improved calculation of $B\to$ light pseudoscalar formfactors
from light-cone sum rules, including one-loop radiative corrections to twist-2
and twist-3 contributions, and leading order twist-4 corrections. The total
theoretical uncertainty of our results at zero momentum transfer is 10 to 13%
and can be improved, at least in part, by reducing the uncertainty of hadronic
input parameters, in particular those describing the twist-2 distribution
amplitudes of the pi, K and eta. We present our results in a way which details
the dependence of the formfactors on these parameters and facilitates the
incorporation of future updates of their values from e.g. lattice calculations.


title: Pentaquark Masses in Chiral Perturbation Theory

abstract:
  Heavy baryon chiral perturbation theory for pentaquarks is applied beyond
leading order. The mass splitting in the pentaquark anti-decuplet is calculated
up to NNLO. An expansion in the coupling of pentaquarks to non-exotic baryons
simplifies calculations and makes the pentaquark masses insensitive to the
pentaquark-nucleon mass difference. The possibility of determining coupling
constants in the chiral Lagrangian on the lattice is discussed. Both positive
and negative parities are considered.


title:
One-loop charge and colour breaking associated with the top Yukawa
  coupling

abstract:
  We calculate the one-loop contributions to the MSSM effective potential when
the scalar top fields have non-zero vacuum expectation values and study their
impact on charge and colour breaking bounds.


title:
The neutral top-pion and the lepton flavor violating $Z$ decays $Z\to
  l_{i}l_{j}$

abstract:
  Taking into account the constraints of the present experimental limit of the
process $\mu\to e\gamma$ on the free parameters of topcolor-assisted
technicolor(TC2) models, we calculate the contributions of the neutral top-pion
to the lepton flavor violating(LFV) $Z$ decays $Z\to l_{i}l_{j}$. Our results
show that the value of the branching ratio $Br(Z\to \tau l)$ is larger than
that of $Br(Z\to \mu e)$ in all of the parameter space and there is $Br(Z\to
\tau\mu)\approx Br(Z\to \tau e)\simeq 2\times 10^{-14} $, which is far from the
reach of present or future experiments.


title: Baryons, IN_c

abstract:
  Excited baryons may be analyzed in the 1/N_c expansion as true resonances in
scattering amplitudes. The key idea making this program possible is a
generalization of methods originally applied to chiral soliton models in the
1980's. One finds model-independent relations among amplitudes that impose mass
and width degeneracies among resonances of various quantum numbers.
Phenomenological evidence demonstrates that patterns of resonant decay
predicted by 1/N_c agree with data. The analysis can be extended to subleading
orders in 1/N_c, where again agreement with data is evident.


title: Flavour-singlet g_A and the QCD sum rule incorporating instanton effects

abstract:
  We derive a QCD sum rule for the flavour-singlet axial coupling constant
$g_A^{(0)}$ from a two point correlation function of flavour-singlet axial
vector currents in a one-nucleon state. In evaluating the correlation function
by an operator product expansion we take into account the terms up to dimension
6. This correlation function receives an additional two-loop diagram which
comes from an (anti-)instanton. If we do not include it, $g_A^{(0)}$ is
estimated to be 0.8. However, the additional diagram due to instantons
contributes negatively and reduces $g_A^{(0)}$ towards the experimental value.


title: The influence of baryons on the chiral phase transition in QCD

abstract:
  A qualitative analysis of the chiral phase transition in QCD with two
massless quarks and non--zero baryon density is performed. It is assumed that
at zero baryonic density, $\rho=0$, the temperature phase transition is of the
second order. Due to a specific power dependence of baryon masses on the chiral
condensate the phase transition becomes of the first order at the temperature
$T=T_{\mathrm{ph}}(\rho)$ for $\rho>0$. At temperatures
$T_{\mathrm{cont}}(\rho) > T > T_{\mathrm{ph}}(\rho)$ there is a mixed phase
consisting of the quark phase (stable) and the hadron phase (unstable). At the
temperature $T = T_{\mathrm{cont}}(\rho)$ the system experiences a continuous
transition to the pure chirally symmetric phase.


title: New Bounds on the String Scale from Flavor Physics

abstract:
  We review the very stringent lower bounds on the string scale that arise from
flavor considerations in models with intersecting branes. Despite the absence
of a realistic flavor structure at tree level, flavor changing interactions
induce a non-trivial pattern of fermion masses and mixing angles when quantum
corrections are taken into account. The resulting realistic theory of flavor
allows us to constrain, in an unambiguous way, the string scale up to levels
difficult to reconcile non-supersymmetric models.


title:
${BR}(\bar{B}\to X_s\gamma)$: First Next-to-Next-to-Leading Order
  Results

abstract:
  In this contribution the first next-to-next-to-leading order corrections to
the branching ratio ${BR}(\bar{B}\to X_s\gamma)$ are discussed. This includes
the completion of the matching part and the fermionic corrections to the most
important operator matrix elements.


title: New possibilities in the study of NLL BFKL

abstract:
  The high energy limit of scattering processes in QCD is, at least on the
purely theoretical level, described by the BFKL equation. However, many
phenomenological studies of BFKL fail miserably when confronted with data. In
this talk we will briefly review the application of (LL) BFKL in phenomenology,
and critically examine the application of LL eigenfunctions in the study of the
NLL BFKL kernel. We then introduce a recently proposed iterative solution of
the NLL BFKL equation that allows for a detailed study of physical properties
of the BFKL evolution.


title:
Classification of the scalar mesons: a strange pole expedition into
  charm and beauty territory

abstract:
  The classification of scalar and vector mesons is reviewed within the
framework of the Resonance-Spectrum Expansion (RSE). This method allows a
simple and straightforward description of non-exotic meson-meson scattering,
incorporating the effects of quark confinement and OZI-allowed decay in a fully
nonperturbative way. Results for resonances and bound states are compared to
experiment, on the basis of computed pole positions and cross sections. New
predictions for open-charm and -bottom scalar mesons are presented.
  Concretely, observed vector states for u-ubar/d-dbar, s-sbar, c-cbar, and
b-bbar are reproduced, and others are predicted. In the light scalar sector,
the now established two nonets, one below 1 GeV and one in the region 1.3 - 1.5
GeV, are easily described, through the appearance of extra poles in the
scattering matrix. The recently found Ds0*(2317) meson is accurately reproduced
by the same mechanism, as a quasi-bound state in the coupled c-sbar/DK system.
  In S-wave D-pion and B-pion scattering, new resonances are foreseen close to
threshold, i.e., a D0* at 2.16(+-0.05) GeV some 250 MeV wide, and a B0* at
5.47(+-0.05) GeV with a width of about 50 MeV. Additional predictions concern
the existence of b-sbar and b-cbar scalar mesons, stable with respect to
OZI-allowed decay to BK and BD, respectively, namely at 5.61(+-0.05) GeV resp.
6.64(+-0.05) GeV.


title: Study of leptonic CP violation

abstract:
  The "complementary" Ansatz, Tr$(M_\nu)=0$, where $M_\nu$ is the prediagonal
neutrino mass matrix, seems a plausible approximation for capturing in a
self-contained way some of the content of Grand Unification. We study its
consequences in the form of relations between the neutrino masses and CP
violation phases.


title:
Are Bulk Axions in Models with Extra, Large, Compact Dimensions
  Observable?

abstract:
  The high degeneracy of KK modes in models which have bulk axions moving in
some extra, compact dimensions which are larger than O (Angstrom)strongly
tightens the supernova upper bounds on the axion photon coupling making axions
practically unobservable. Conversely, discovering axions directly or indirectly
will exclude such models. These drastic conclusions are avoided if the
supernova and bounds from solar axion searches are relaxed.


title: Precision SUSY Physics

abstract:
  We review the theoretical status and the future perspectives of the most
important electroweak precision observables in the MSSM. This comprises the
mass of the W boson, M_W, the effective leptonic mixing angle,
sin^2(theta_eff), the mass of the lightest MSSM Higgs boson, m_h, and the
anomalous magnetic moment of the muon, a_\mu. The impact of the parametric
uncertainties from the experimental errors of the input parameters is studied,
and an estimate for the remaining uncertainties from unknown higher-order
corrections is given. The need for future improvements in the theory
predictions is investigated.


title: A Comparative Study of Pentaquark Interpolating Currents

abstract:
  In a diquark-diquark-antiquark picture of pentaquarks, we use two
interpolating currents to calculate the mass of the recently measured
$\Xi^{--}$ state in the framework of QCD sum rules. We show that, even though
yielding similar values for $m_{\Xi^{--}}$ (and close to the experimental
value), these currents differ from each other in what concerns the strength of
the pole, convergence of the OPE and sensitivity to the continuum threshold
parameter.


title: New-Physics Search in gamma gamma --> t tbar

abstract:
  We performed an analysis on possible anomalous top-quark couplings generated
by SU(2) x U(1) gauge-invariant dimension-6 effective operators, applying the
optimal-observable procedure to the final lepton/b-quark momentum distribution
in gamma gamma --> t tbar --> l X/b X. We studied how many such anomalous
coupling constants could be determined altogether through these distributions.


title: Search for time modulations in the Gallex/GNO solar neutrino data

abstract:
  The final data of the Gallex and GNO radiochemical experiments have been
searched for possible time modulations of the solar neutrino capture rate using
the Lomb-Scargle periodogram and the maximum likelihood methods. Both analyses,
performed using the raw data, do not support the presence of a time variability
with characteristic periods resembling those of rotation of the solar magnetic
fields, as previously suggested in the literature by some authors. In this
context, the potential sensitivity of the Lomb-Scargle method to radiochemical
71Ga data has also been explored with simulated data. This allowed to set an
exclusion plot in the frequency/amplitude plane from the Gallex-GNO dataset.


title:
Pairing in Many-Fermion Systems: An Exact Renormalisation Group
  Treatment

abstract:
  We study the application of the exact renormalisation group to a many-fermion
system with a short-range attractive force. We introduce a boson field to
describe pairing effects, and take a simple ansatz for the effective action. We
derive a set of approximate flow equations for the effective coupling including
boson and fermionic fluctuations. The initial conditions are obtained by
renormalising the interaction to fit the scattering length in vacuum. At some
critical value of the running scale, the numerical solutions show a phase
transition to a gapped phase. Standard results are recovered if we omit the
boson loops. When boson fluctuations are included, we find that their
contributions are significant only in the small-gap regime.


title: From chemical freezeout to critical conditions in heavy ion collisions

abstract:
  We compare the statistical thermodynamics of hadron resonance gas with recent
LGT results at finite chemical potential. We argue that for $T\leq T_c$ the
equation of state derived from
  Monte--Carlo simulations of two quark--flavor QCD at finite chemical
potential is consistent with that of a hadron resonance gas when applying the
same set of approximations as used in LGT calculations.
  We indicate the relation of chemical freezeout conditions obtained from a
detailed analysis of particle production in heavy ion collisions with the
critical conditions required for deconfinement. We argue that the position of a
hadron--quark gluon boundary line in temperature chemical potential plane can
be determined in terms of the resonance gas model by the condition of fixed
energy density.


title:
Pair production in a strong magnetic field: the effect of a strong
  background gravitational field

abstract:
  We present the calculation of the probability production of an
electron-positron pair in the presence of a strong magnetic field with
time-varying strength. The calculation takes into account the presence of a
strong, constant and uniform gravitational field in the same direction of the
magnetic field. The results show that the presence of the gravitational field
in general enhances the production of pairs. In particular, high-energy pairs
are more likely produced in the presence of the gravitational field than in
Minkowski spacetime.


title:
New experimental limits on violations of the Pauli exclusion principle
  obtained with the Borexino Counting Test Facility

abstract:
  The Pauli exclusion principle (PEP) has been tested for nucleons ($n,p$) in
$^{12}C$ and $^{16}O$ nuclei, using the results of background measurements with
the prototype of the Borexino detector, the Counting Test Facility (CTF). The
approach consisted of a search for $\gamma$, $n$, $p$ and/or $\alpha$'s emitted
in a non-Paulian transition of 1$P$- shell nucleons to the filled 1$S_{1/2}$
shell in nuclei. Similarly, the Pauli-forbidden $\beta^{\pm}$ decay processes
were searched for. Due to the extremely low background and the large mass (4.2
tons) of the CTF detector, the following most stringent up-to-date experimental
bounds on PEP violating transitions of nucleons have been established:
$\tau(^{12}C\to^{12}\widetilde{C}+\gamma) > 2.1\cdot10^{27}$ y,
$\tau(^{12}C\to^{11}\widetilde{B}+ p) > 5.0\cdot10^{26}$ y,
$\tau(^{12}C(^{16}O)\to^{11}\widetilde{C}(^{15}\widetilde{O})+ n) > 3.7 \cdot
10^{26}$ y, $\tau(^{12}C\to^{8}\widetilde{Be}+\alpha) > 6.1 \cdot 10^{23}$ y,
$\tau(^{12}C\to^{12}\widetilde{N}+ e^- + \widetilde{\nu_e})> 7.6 \cdot 10^{27}$
y and $\tau(^{12}C\to^{12}\widetilde{B}+ e^+ + \nu_e)> 7.7 \cdot 10^{27}$ y,
all at 90% C.L.


title:
Testing soft electroweak SUSY breaking from neutralino, chargino, and
  charged Higgs boson pairs production at linear colliders

abstract:
  We consider the production of neutralino, chargino, and charged Higgs boson
pairs in the MSSM framework at future $e^+e^-$ colliders. We show that, for
c.m. energies in the one TeV range and in a ``moderately'' light SUSY scenario,
a combined analysis of the slopes of these production cross sections could lead
to a strong consistency test involving the soft supersymmetric breaking
parameters $M_1$, $M_2$, the Higgsino parameter $\mu$, and $\tan\beta$.


title: Relation between bottom-quark MS-bar Yukawa coupling and pole mass

abstract:
  We calculate the O(alpha alpha_s) corrections to the relationships between
the MS-bar Yukawa couplings and the pole masses of the first five quark
flavours in the standard model. We also present the corresponding relationships
between the MS-bar and pole masses, which emerge as by-products of our main
analysis. The occurring self-energies are evaluated using the method of
asymptotic expansion.


title: Lorentz Violation and Short-Baseline Neutrino Experiments

abstract:
  A general discussion is given of signals for broken Lorentz symmetry in
short-baseline neutrino experiments. Among the effects that Lorentz violation
can introduce are a dependence on energy differing from that of the usual
massive-neutrino solution and a dependence on the direction of neutrino
propagation. Using the results of the LSND experiment, explicit analysis of the
effects of broken Lorentz symmetry yields a nonzero value (3+/-1) x 10^{-19}
GeV for a combination of coefficients for Lorentz violation. This lies in the
range expected for effects originating from the Planck scale in an underlying
unified theory.


title:
Associated production of a light Higgs boson and a chargino pair in the
  MSSM at linear colliders

abstract:
  In the Minimal Supersymmetric Standard Model (MSSM), we study the light
Higgs-boson radiation off a light-chargino pair in the process e+e- -> h chi^+
chi^- at linear colliders with \sqs=500 GeV. We analyze cross sections in the
regions of the MSSM parameter space where the process can not proceed via
on-shell production and subsequent decay of either heavier charginos or the
pseudoscalar Higgs boson A. Cross sections up to a few fb's are allowed,
according to present experimental limits on the Higgs-boson, chargino and
sneutrino masses. We also show how a measurement of the process production rate
could provide a determination of the Higgs-boson couplings to charginos.


title:
Unconventional fermions: The Price of Quark-Lepton Unification at TeV
  Scales

abstract:
  The early petite unification (PUT) of quarks and leptons at TeV scales with
sin^2 theta_W(M^2_Z) used as a constraint, necessitates the introduction of
extra quarks and leptons with unconventional electric charges (up to 4/3 for
the quarks and 2 for the leptons). This talk, in honor of Paul Frampton's 60th
birthday, will be devoted to the motivation and construction of models of early
unification and to their implications, including the issues of rare decays and
unconventional fermions.


title:
A study of the pion effective mass at finite temperature using the
  linear sigma model

abstract:
  We have used the Cornwall--Jackiw--Tomboulis method of composite operators
and its formulation at finite temperature by Amelino-Camelia and Pi, in order
to calculate the effective potential of the O(4) linear sigma model beyond the
Hartree approximation. We have obtained a system of gap equations for the
effective mass of sigma and the pions as well as for the condensate, the order
parameter of the chiral phase transition. We find that the thermal effective
mass of the pions at low temperatures remains lower than in the Hartree case,
nevertheless deviates from the chiral limit. Our observation is consistent with
other results which have been published previously.


title:
"Atmospheric Neutrino" and "Proton Decay" Data Exclude Some New Dark
  Matter Scenarios

abstract:
  Models in which the "dark" halo particles have mutual and potentially also
appreciable nuclear interactions have been considered by various authors. In
this note we briefly point out strategies for a most sensitive search for these
particles. We show that a particular matter/anti-matter symmetric variant due
to Farrar et al. is excluded by combining bounds on proton decay from various
experiments and from super-Kamiokande and atmospheric neutrino measurements at
super-Kamiokande.


title: Effect of a Magnetic Field on the Electroweak Symmetry

abstract:
  We discuss the effect of a strong magnetic field in the behavior of the
symmetry of an electrically neutral electroweak plasma. We analyze the case of
a strong field and low temperatures as compared with the W rest energy. If the
magnetic field is large enough, it is self-consistently maintained. Charged
vector bosons play the most important role, leading only to a decrease of the
symmetry breaking parameter, the symmetry restoration not being possible.


title: B->pi,K,eta Decay Formfactors from Light-Cone Sum Rules

abstract:
  We present an improved calculation of all B -> light pseudoscalar formfactors
from light-cone sum rules, including one-loop radiative corrections to twist-2
and twist-3 contributions, and leading order twist-4 corrections. The total
theoretical uncertainty of our results at zero momentum transfer is 10 to 13%.
The dependence of the formfactors on the momentum transfer q^2 is parametrized
in a simple way that is consistent with their analytical properties and is
valid for all physical q^2. The uncertainty of the extrapolation in q^2 on the
semileptonic decay rate Gamma(B -> pi e nu) is estimated to be 5%.


title:
Neutrino Masses and Mixings in a Predictive SO(10) Model with CKM CP
  Violation

abstract:
  It has recently been shown that a minimal SO(10) model with a single {\bf 10}
and single {\bf 126} Higgs field breaking B-L symmetry predicts large solar and
atmospheric mixings in agreement with observations if it is assumed that the
neutrino mass obeys the type II seesaw formula. No additional symmetries need
to be assumed for this purpose. Understanding CP violation in the
renormalizable version of the model however requires a significant non-CKM
source. In this paper we show that if we extend the model by the inclusion of a
heavy {\bf 120} dimensional Higgs field, then it can accomodate CKM CP
violation while remaining predictive in the neutrino sector. Among the
predictions are:(i) solar mixing angle in the observed range; (ii)\theta_{13}
in the range of 0.1 to 0.26; (iii) the Dirac phase close to maximal for the
central value of the solar mixing angle.


title: Isospin constraints from/on B->pipi

abstract:
  The Standard Model constraints on alpha which can be derived from the B->
pipi decays are revisited in some depth. As experimental inputs, the three
branching ratios, the two CP parameters Spipi and Cpipi and/or the value of
alpha as determined by the global CKM fit are used. The constraints discussed
here are model independent in the sense that they rely only on Isospin
symmetry, following the Gronau-London proposal. A new bound on B00 and the
function C00(B00) are introduced. The Grossman-Quinn bound is rediscussed. A
close form expression is given for alpha as a function of the measurements.
Various scenarii for the future of the isospin analysis are explored. To probe
the Standard Model the (B00,C00) plane is introduced.


title: Top flavour violating decays in general supersymmetric models

abstract:
  We analyse the top flavour violating decays in general supersymmetric model
using the mass insertion approximation. In particular, we discuss the impact of
a light right-handed top-squark and large mixing between the first or second
and third generation of up-squarks on processes as t -> q gamma,g . We also
take into account the relevant experimental constraints from B-physics and the
requirements for a successfull electroweak baryogenesis on squark mixings. We
show that for general large mixings in squarks mass matrix, the branching ratio
of the t -> q gamma, g (q=u,c) can be as large as 10^{-6}.


title:
Flavor changing neutral currents from lepton and B decays in the two
  Higgs doublet model

abstract:
  Constraints on the whole spectrum of lepton flavor violating vertices are
shown in the context of the standard two Higgs doublet model. The vertex
involving the $e-\tau $ mixing is much more constrained than the others, and
the decays proportional to such vertex are usually very supressed. On the other
hand, bounds on the quark sector are obtained from leptonic decays of the
$B_{d,s}^{0}$ mesons and from $\Delta M_{B_{d}^{0}}$. We emphasize that
although the $B_{d}^{0}-\bar{B}_{d}^{0}$ mixing restricts severely the $% d-b$
mixing vertex, the upper bound for this vertex could still give a sizeable
contribution to the decay $B_{d}^{0}\to \mu \bar{\mu}$ respect to the standard
model contribution, from which we see that such vertex could still play a role
in the phenomenology.


title:
Effective potential analysis for 5D SU(2) gauge theories at finite
  temperature and radius

abstract:
  We calculate the one loop effective potential for a 5D SU(2) gauge field
theory at finite temperature $T=1/\beta$ and radius R=1/M. This calculation is
performed, for the first time, in the case of background fields with two
constant components $A^{3}_{y}$ (directed towards the compact extra dimension
with radius R) and $A^{3}_{\tau}$ (directed towards the compact Euclidean time
with radius $\beta$). This model possesses two discrete symmetries known as
Z_{M}(2) and Z_{T}(2). The corresponding phase diagram is presented in Ref. 4.
However the arguments which lead to this diagram are mainly qualitative. We
present a detailed analysis, from our point of view, for this phase diagram,
and we support our arguments performing lattice simulations for a simple
phenomenological model with two scalar fields interacting through the
previously calculated potential.


title: Hadron pair photoproduction within the Veneziano model

abstract:
  We first suppose that low-energy hadron pair photoproduction reactions
gamma(*) gamma(*) -> h h-bar are dominated by s-channel resonance
contributions. Their normalization is then calculated by their correspondence
with the Reggeon term in the Regge parametrization of the gamma h total cross
sections. For the case of p p-bar, we make use of the measured gamma p total
cross section, and for the case of K+K-, we make use of the corresponding total
cross section that is estimated using Regge factorization. For hadrons that
have no such data, we can only provide rough estimation based on the additive
quark rule. As an effective approach that is convenient and parameter-free, we
adopt the Veneziano model in the simplest form. The model is only applicable to
the region of low centre-of-mass energy. When the transverse momentum is large,
perturbative QCD takes over, whereas in the Regge region, it is known that the
Regge pole picture fails in photoproduction. Despite the shortcomings of the
model, we find that the parameter-free amplitudes offer a sound description of
the data at hand.


title: Neutrino Mixing and Leptogenesis in Type II Seesaw Mechanism

abstract:
  In the framework of type II seesaw mechanism we propose two simple but
instructive ansatze for neutrino mixing and leptogenesis. In each ansatz, the
effective Majorana neutrino mass matrix is composed of two parts -- the part
with Z_2 symmetry arises from the ordinary type I seesaw mechanism and the part
with S_3 symmetry arises from an additional Higgs triplet vacuum expectation
value. The two ansatze can simultaneously account for the current neutrino
oscillation data and the cosmological baryon number asymmetry via leptogenesis.