title: Plato's Fire and the Neutrino Mass Matrix

abstract:
  With the accumulation of many years of solar and atmospheric neutrino
oscillation data, the approximate form of the 3 X 3 neutrino mixing matrix is
now known. The theoretical challenge is to understand where this mixing matrix
comes from. Recently, a remarkable fact was discovered that for a specific
pattern of the neutrino mass matrix at a high scale, any flavor-changing
radiative correction will automatically lead to the desired mixing matrix. It
was also discovered that the required specific pattern at the high scale can be
maintained by the non-Abelian discrete symmetry A_4 which is also the symmetry
group of the regular tetrahedron, one of five perfect geometric solids known to
Plato who associated it with the element ``fire''. I discuss this recent
development and add to it a new and very simple mechanism for the
implementation of the flavor-changing radiative correction.


title: Manifest CP Violation from Majorana Phases

abstract:
  We hunt for and discuss manifestly CP-violating effects which are mediated by
Majorana phases. These phases are present if the Standard Model neutrinos are
Majorana particles. We argue that while Majorana phases do affect the strength
of neutrinoless double beta decay (a well known fact), they do so in a way that
involves no manifest violation of CP. The conditions for manifestly
CP-violating phenomena -- differences between the rates for CP-mirror-image
processes -- are presented, and three examples are discussed: (i)
neutrino-antineutrino oscillation; (ii) rare decays of K and B mesons and their
antiparticles and (iii) the lepton asymmetry generated by the decay of
hypothetical very heavy right-handed "see-saw" neutrinos. We also find that,
for the case of degenerate light neutrinos, manifestly CP-violating effects in
neutrino-antineutrino oscillation vanish, although flavor-changing transitions
do not. Finally, we comment on leptogenesis with degenerate right-handed
neutrinos, and contrast it to the neutrino-antineutrino oscillation case.


title: Graviton and Radion Production at LHC: From pp and PbPb Collisions

abstract:
  If the Planck scale is around a TeV in theories with large extra dimension,
then gravitons should be produced in high energy hadronic collisions at the
LHC. In this paper we compute the direct graviton production cross section in a
pp and PbPb collision at LHC at \sqrt s^{NN}= 14 TeV and 5.5 TeV respectively.
The graviton production cross section in a lead-lead collision is enhanced in
comparison to a pp collision at LHC depending upon the minimum transverse
energy of the jet E_{T,jet}^{min} above which the graviton production cross
section is computed. For two extra dimensions and above E_{T,jet}^{min} = 100,
500, 1000, 1500 GeV the ratio of graviton production cross sections in a PbPb
collision to that in a pp collision is found to be 2220, 400, 43, 2. For four
extra dimensions this ratio is found to be 470, 100, 10, 0.5. In the
Randall-Sundrum model the radion production cross section is also found to be
enhanced in a lead-lead collision over that in a pp collision at LHC. The ratio
of the radion production cross sections in a PbPb collision to that in a pp
collision at LHC is found to be 1650, 460, 180, 67, 23, 1 for radion of masses
100, 500, 1000, 1500, 2000, 3000 GeV respectively.


title:
Higgs Mass from Casimir Energy Induced Cosmological Constant in the
  Standard Model

abstract:
  Casimir vacuum energy is divergent. It needs to be regularized. The
regularization introduces a renormalization scale which may lead to a scale
dependent cosmological constant. We show that the requirement of physical
cosmological constant is renormalization scale independent provides important
constraints on possible particle contents and their masses in particle physics
models. In the Standard Model of strong and electroweak interactions, besides
the Casimir vacuum energy there is also vacuum energy induced from spontaneous
symmetry breaking. The requirement that the total vacuum energy to be scale
independent dictates the Higgs mass to be $m_H^4 = 8\sum_i N_i m^4_i - 12m^4_W
- 6 m^4_Z$, where the summation is over fermions and $N_i$ equals to 3 and 1
for quarks and leptons, respectively. The Higgs mass is predicted to be
approximately 382 GeV.


title:
An Accelerating Universe from Dark Matter Interactions with Negative
  Pressure

abstract:
  As an explanation for the acceleration of the universe, we propose dark
matter with self-interactions characterized by a negative pressure; there is no
vacuum energy whatsoever in this Cardassian model. These self-interactions may
arise due to a long-range "fifth force" which grows with the distance between
particles. We use the ordinary Friedmann equation, $H^2 = 8 \pi G \rho/3$, and
take the energy density to be the sum of two terms: $\rho = \rho_M + \rho_K$.
Here $\rho_M \equiv m n_M$ is the ordinary mass density and $\rho_K \equiv
\rho_K(\rho_M)$ is a new interaction term which depends only on the matter
density. For example, in the original version of the Cardassian model, $\rho_K
= b \rho_M^n$ with $n<2/3$; other examples are studied as well. We use the
ordinary four-dimensional Einstein's equations $G_{\mu\nu} = 8 \pi G T_{\mu\nu}
$ and assume a perfect fluid form for the energy momentum tensor. Given this
ansatz, we can compute the accompanying pressure, and use the conservation of
the energy-momentum tensor to obtain modified forms of the Euler's equation,
Poisson equation, and continuity equation. With this fully relativistic
description, one will then be able to compute growth of density perturbations,
effects on the Cosmic Background Radiation, and other effects with an eye to
observational tests of the model.


title: Diphoton production in gluon fusion at small transverse momentum

abstract:
  We discuss the production of photon pairs in gluon-gluon scattering in the
context of the position-space resummation formalism at small transverse
momentum. We derive the remaining unknown coefficients that arise at
$O(\alpha_S)$, as well as the remaining $O(\alpha_S^2)$ coefficient that occurs
in the Sudakov factor. We comment on the impact of these coefficients on the
normalization and shape of the resummed transverse momentum distribution of
photon pairs, which comprise an important background to Higgs boson production
at the LHC.


title: Axially symmetric B=2 solution in the chiral quark soliton model

abstract:
  The baryon-number-two (B=2) solution based on the SU(2) chiral quark soliton
model ($\chi$QSM) is solved numerically, including fully the sea quark degrees
of freedom. We confirm that the axially symmetric meson configurations yield
the energy minimum for the B=2 state in the $\chi$QSM when taking into account
quark dynamics. Due to the axially symmetric meson fields, six valence quarks
occupy the lowest energy level, consistent with the Pauli exclusion principle.
The minimal-energy of the entire system is obtained within the framework of a
symmetric ansatz. The fermion determinant with axially symmetric meson fields
is calculated by diagonalizing the corresponding Dirac hamiltonian in a
non-perterbative way, using a cylindrical Dirac basis. The baryon number
density, calculated with quark fields corresponding to a soliton, is toroidal
in shape. We also calculate the mean radius of the toroid from the quark
fields. These results are closely related to Skyrme model calculations based
upon pion degrees of freedom. Our model calculations clarify the underlying
dynamical structure of the baryons at the quark level.


title:
Single Transverse Spin Asymmetry in $p^\uparrow p \to \pi X$ and
  $ep^\uparrow \to \pi X$

abstract:
  Single transverse spin asymmetry for the pion production in pp and ep
collisions is studied in the framework of collinear factorization. The
soft-gluon pole contributions with twist-3 distribution and fragmentation
functions are identified and its characteristic features are discussed.


title:
A Flexible Parametrization of CKM matrix via
  Singular-Value-Decomposition Method

abstract:
  We investigate a flexible method in which we can test the unitarity of the
quark flavor mixing matrix step-by-step. Singular-Value-Decomposition (SVD)
techniques are used in analyzing the mixing matrix over a broader parameter
region than the unitarity region. Unitary constraints make us extract CP
violating properties without any specific parametrization when the magnitudes
of at least three mixing matrix elements in three generation quark mixing are
given. This method can also be applied to the analysis of lepton flavor mixing,
in which only a few moduli are presently measured.


title:
Perturbative and nonperturbative aspects of azimuthal asymmetries in
  polarized ep

abstract:
  We discuss the possibilities of testing of perturbative quantum
chromodynamics through azimuthal asymmetries in polarized ep in the context of
future collider and fixed target facilities, such as Electron Ion Collider and
TESLA-N.


title:
Search for the quark shell structure using the non-topological soliton
  model

abstract:
  We investigate higher baryon-number states in the Chiral Quark Soliton Model
using the rational map ansatz for the background chiral fields. The soliton
solutions are obtained self-consistently. We show that the baryon number
density has point-like symmetries and the corresponding valence quark spectrum
of the lowest energy exhibits approximate four-fold degenerate. Our results
indicate the possibility of existence of the shell-like structure in the
multi-baryonic system.


title:
Radiatively Generated $\nu_e$ Oscillations: General Analysis, Textures
  and Models

abstract:
  We study the consequences of assuming that the mass scale $\Delta_{odot}$
corresponding to the solar neutrino oscillations and mixing angle $U_{e3}$
corresponding to the electron neutrino oscillation at CHOOZ are radiatively
generated through the standard electroweak gauge interactions. All the leptonic
mass matrices having zero $\Delta_{odot}$ and $U_{e3}$ at a high scale lead to
a unique low energy value for the $\Delta_{odot}$ which is determined by the
(known) size of the radiative corrections, solar and the atmospheric mixing
angle and the Majorana mass of the neutrino observed in neutrinoless double
beta decay. This prediction leads to the following consequences: ($i$) The MSSM
radiative corrections generate only the dark side of the solar neutrino
solutions. ($ii$) The inverted mass hierarchy ($m,-m,0$) at the high scale
fails in generating the LMA solution but it can lead to the LOW or vacuum
solutions. ($iii$) The $\Delta_{odot}$ generated in models with maximal solar
mixing at a high scale is zero to the lowest order in the radiative parameter.
It tends to get suppressed as a result of this and lies in the vacuum region.
We discuss specific textures which can lead to the LMA solution in the present
framework and provide a gauge theoretical realization of this in the context of
the seesaw model.


title:
Two-photon Width and Phase Measurement from the SM Higgs Decays into WW
  and ZZ

abstract:
  Production of the Standard Model Higgs-boson at the photon collider at TESLA
is studied for the Higgs-boson masses above 170 GeV. By reconstructing WW and
ZZ final states, not only the h to gamma-gamma partial width but also the phase
of the scattering amplitude can be measured. This opens a new window onto the
precise determination of the Higgs-boson couplings.


title: Detailed analysis of the decay spectrum of a super-heavy X particle

abstract:
  Decays of superheavy X particles with mass M_X ~ 10^12 - 10^16 GeV have been
proposed as origin of the observed ultra high energy cosmic rays (UHECR). We
describe in detail the physics involved in the different steps of the decay of
such a particle. In particular, we give for the first time the complete set of
splitting functions needed to model a parton shower in the minimal
supersymmetric extension of the Standard Model (MSSM). We present our results
in the form of fragmentation functions of any (s)particle of the MSSM into any
final stable particle (proton, photon, electron, three types of neutrino,
lightest superparticle LSP) at a virtuality Q = M_X, over a scaled energy range
x = 2E/M_X in [10^{-13}, 1]. Extending the coverage to such small fractional
energies is necessary since the energy region around 10^18 eV and below could
be of considerable interest in testing this kind of model for generating UHECR.
We explicitly demonstrate that our treatment conserves energy, and discuss the
dependence of the final result on SUSY parameters. We also show that our
results are essentially independent of the necessary extrapolation of the input
fragmentation functions, which are known only for x >= 0.1, towards small x.
Finally, we added a new treatment of the color coherence effects at very small
x, using the analytic ``MLLA'' solution. Our computer code will soon be made
available.


title: CP-odd phases at NLC: a project outline

abstract:
  Low-energy results from measurements of leptonic dipole operators are used to
derive constraints on phases of the MSSM. After rediscovering older bounds on
these phases, we try to investigate the impact of these possibly non-vanishing
CP-odd phases on the measurement of CP-even cross-sections at the next leptonic
collider.


title: From Parity Violation to Hadron Structure and more

abstract:
  New developments in physics associated with parity-violating interactions are
discussed in this PAVI 2002 workshop summary.


title:
Brane to bulk supersymmetry breaking and radion force at micron
  distances

abstract:
  We study mediation of supersymmetry breaking in the bulk, in models with
primordial supersymmetry breaking on D-branes at the string scale, in the TeV
region. We compute the gravitino and scalar masses up to one-loop level, as
well as the radion coupling to matter. We find that the latter mediates a model
independent force at submillimeter distances that can be tested in
micro-gravity experiments for any dimensionality of the bulk. In the case of
two large dimensions, our type I string framework provides an example which
allows to stabilize the radion potential and determine the desired hierarchy
between the string and Planck scales.


title: Nonperturbative mechanisms of strong decays in QCD

abstract:
  Three decay mechanisms are derived systematically from the QCD Lagrangian
using the field correlator method. Resulting operators contain no arbitrary
parameters and depend only on characteristics of field correlators known from
lattice and analytic calculations. When compared to existing phenomenological
models, parameters are in good agreement with the corresponding fitted values.


title: The light scalar mesons within quark models

abstract:
  Low-energy meson-meson scattering data are a powerful testing ground for
quark models. Here, we describe the behaviour at threshold of S-wave
scattering-matrix singularities.
  The majority of the full scattering-matrix mesonic poles stem from an
underlying confinement spectrum. However, the light scalar mesons K0*(830),
a0(980), f0(400-1200), and f0(980) do not, but instead originate in 3P0-barrier
semi-bound states. We show that the behaviour of the corresponding poles is
identical at threshold.
  In passing, the light-meson sector is given a firm basis.


title: Progress in NNLO calculations for scattering processes

abstract:
  The various motivations for improving the perturbative prediction to
next-to-next-to-leading order (NNLO) for basic scattering processes in
proton-(anti)proton, electron-proton and electron-positron scattering are
discussed in detail. Recent progress in the field of next-to-next-to-leading
order calculations is reviewed.


title: Final State Interactions in $D \to PP$ decays

abstract:
  The two-body nonleptonic charmed meson decays into two pseudoscalar mesons
are studied using one-particle-exchange method. The effects of the final state
interactions are analyzed through the strong phases extracted from the
experimental data.


title: Solar neutrino oscillations and indications of matter effects in the Sun

abstract:
  Assuming the current best-fit solutions to the solar neutrino problem at
large mixing angle, we briefly illustrate how prospective data from the Sudbury
Neutrino Observatory (SNO) and from the Kamioka Liquid scintillator
Anti-Neutrino Detector (KamLAND) can increase our confidence in the occurrence
of standard matter effects on active neutrino flavor oscillations in the Sun,
which are starting to emerge from current data.


title:
Double-logarithmic (Sudakov) asymptotics at the theory of electroweak
  interactions

abstract:
  Accounting for double-logarithmic contributions to high-energy (>> 100 GeV)
e^+ e^- annihilation into a quark or a lepton pair in the kinematics where the
final particles are colinear to the e^+e^- beams leading to a sizable
difference between the forward and backward scattering amplitudes, i.e. to the
forward-backward asymmetry. When the annihilation is accompanied by emission of
n electroweak bosons in the multi-Regge kinematics, it turns out that the cross
sections of the photon and Z production have the identical energy dependence
and asymptotically their ratio depends only on the Weinberg angle (is equal to
tan^{2n} theta_W) whereas the energy dependence of the cross section of the W
production is suppressed by factor s^{-0.4} compared to them.


title: Ward identity in noncommutative QED

abstract:
  Although noncommutative QED presents a nonabelian structure, it does not
present structure constants. In view of this we investigate how Ward identity
is satisfied in pair annihilation process and $\gamma \gamma \to \gamma \gamma$
scattering in noncommutative QED.


title: Dark Matter, Muon g - 2 And Other Accelerator Constraints

abstract:
  We review the current status of the Brookhaven muon g - 2 experiment, and
it's effects on the SUSY parameter space when combined with dark matter relic
density bounds, b->s\gamma and Higgs mass constraints. If the 3\sigma deviation
of g - 2 from the Standard Model value is correct, these data constrain the
mSUGRA parameter space strongly, i.e. 300 GeV <~m_{1/2}<~850 GeV, and m_0 (at
fixed \tan\beta, A_0) is tightly constrained (except at very large \tan\beta).
Dark matter detection cross sections lie within the range accessible to future
planned experiments. A non-universal gluino soft breaking mass however can
greatly reduce the lower bound on m_{1/2} (arising from the b->s\gamma
constraint) allowing for relatively light neutralinos, while non-universal
Higgs H_2 mass can lead to new regions of allowed relic density where the
detection cross sections can be increased by a factor of 10 or more.


title: Are supersymmetric models with large tan(beta) natural ?

abstract:
  We point out that, contrary to general belief, generic supersymmetric models
are not technically unnatural in the limit of very large values of the
parameter tan(beta) when radiative corrections are properly included. Rather,
an upper limit on tan(beta) only arises from the requirement that Yukawa
couplings remain perturbative up to some high scale. We quantify the relation
between this scale and the maximum value of tan(beta). Whereas tan(beta) is
limited to lie below 50-70 in the mSUGRA model, models with a much lower scale
of new physics (beyond supersymmetry) may have tan(beta) < 150-200.


title: Collider Implications of Models with Extra Dimensions

abstract:
  We discuss the collider signals of large extra dimensions in which gravity as
well as the SM particles propagate into the extra dimensions. These signals
arise either from the production of Kaluza-Klein excitations of the SM
particles and their subsequent decay, or from their off-shell exchanges.
Depending on the scenario, the dominant signals are two high p_T jets + missing
energy, two high p_T photons + missing energy and soft leptons, or a
combination of photon + jet and missing energy. For the scenario in which only
the gauge bosons propagate into the extra dimensions, Tevatron Run II (LHC) can
observe such signals up to a compactification scale of about 2 TeV (7 TeV),
while for the case of universal extra dimensions, the corresponding limits are
about 600 GeV (3 TeV) respectively.


title:
Improved Determination of the Electroweak Penguin Contribution to
  epsilon'/epsilon in the Chiral Limit

abstract:
  We perform a finite energy sum rule analysis of the flavor ud two-point V-A
current correlator, Delta Pi (Q^2). The analysis, which is performed using both
the ALEPH and OPAL databases for the V-A spectral function, Delta rho, allows
us to extract the dimension six V-A OPE coefficient, a_6, which is related to
the matrix element of the electroweak penguin operator, Q_8, by chiral
symmetry. The result for a_6 leads directly to the improved (chiral limit)
determination epsilon'/epsilon = (- 15.0 +- 2.7) 10^{-4}. Determination of
higher dimension OPE contributions also allows us to perform an independent
test using a low-scale constrained dispersive analysis, which provides a highly
nontrivial consistency check of the results.


title: Grand Unification and Time Variation of the Gauge Couplings

abstract:
  Astrophysical indications that the fine structure constant is time dependent
are discussed in the framework of grand unification models. A variation of the
electromagnetic coupling constant could either be generated by a corresponding
time variation of the unified coupling constant or by a time variation of the
unification scale, or by both. The case in which the time variation of the
electromagnetic coupling constant is caused by a time variation of the
unification scale is of special interest. It is supported in addition by recent
hints towards a time change of the proton-electron mass ratio. Possible
implications for baryogenesis are discussed.


title:
Relating parton model and color dipole formulation of heavy quark
  hadroproduction

abstract:
  At high center of mass energies, hadroproduction of heavy quarks can be
expressed in terms of the same color dipole cross section as low Bjorken-x deep
inelastic scattering. We show analytically that at leading order, the dipole
formulation is equivalent to the gluon-gluon fusion mechanism of the
conventional parton model. In phenomenological application, we employ a
parameterization of the dipole cross section which also includes higher order
and saturation effects, thereby going beyond the parton model. Numerical
calculations in the dipole approach agree well with experimental data on open
charm production over a wide range of energy. Dipole approach and next to
leading order parton model yield similar values for open charm production, but
for open bottom production, the dipole approach tends to predict somewhat
higher cross sections than the parton model.


title: Angular Distribution of Drell Yan Pairs in p+A at LHC

abstract:
  We discuss the angular distribution of dilepton pairs in p+A collisions at
LHC at low momentum transfer and transverse momentum. This includes helicity
amplitudes and angular coefficients as well as a look at the Lam-Tung sum rule.
We use leading twist NLO calculations and higher twist corrections by double
scattering in large nuclei.


title:
Recent measurements of proton electric form factor and antiproton-proton
  elastic scattering

abstract:
  The Chou-Yang model based on multiple diffraction theory has already been
used by us to predict the characteristics of antiproton-proton elastic
scattering at very high energies. But the recent precise data on proton elastic
form factor obtained at JLab essentially deviates from the dipole
approximation. We have parametrized the data for the form factor. The
computations have been made by using the new expression for the form factor.
The implications of the new form factor on the characteristics of
antiproton-proton elastic scattering at very high energy have been studied.


title:
Some Phenomenological Consequences of the Time-Ordered Perturbation
  Theory of QED on Noncommutative Spacetime

abstract:
  A framework was recently proposed for doing perturbation theory on
noncommutative (NC) spacetime. It preserves the unitarity of S matrix and
differs from the naive, popular approach already at the lowest order in
perturbation when time does not commute with space. In this work, we
investigate its phenomenological implications at linear colliders, especially
the TESLA at DESY, through the processes of e^+e^-\to\mu^+\mu^-,H^+H^-,H^0H^0.
The results are indeed found to be very different from the ones obtained in the
naive approach. The first two get corrected at tree level as opposed to the
null result in the naive approach, while the third one coincides with the naive
result only in the low energy limit. The impact of the Earth rotation is
incorporated. The NC signals are generally significant when the NC scale is
comparable to the collider energy. If this is not the case, the nontrivial
azimuthal angle distribution and day-night asymmetry of events due to Lorentz
violation and the Earth rotation will be useful in identifying signals. We also
comment briefly on the high energy behaviour of the cross section that grows up
linearly in the center of mass energy squared and argue that it does not
necessarily contradict some statements, e.g., the Froissart-Martin bound,
achieved in ordinary theory.


title:
Non-global logarithms in inter-jet energy flow with kt clustering
  requirement

abstract:
  Recent work in inter-jet energy flow has identified a class of leading
logarithms previously not considered in the literature. These so-called
non-global logarithms have been shown to have significant numerical impact on
gaps-between-jets calculations at the energies of current particle colliders.
Here we calculate, at fixed order and to all orders, the effect of applying
clustering to the gluonic final state responsible for these logarithms for a
trivial colour flow 2 jet system. Such a clustering algorithm has already been
used for experimental measurements at HERA. We find that the impact of the
non-global logarithms is reduced, but not removed, when clustering is demanded,
a result which is of considerable interest for energy flow observable
calculations.


title: F-flatness and universality in broken Supergravity

abstract:
  We show that in a broken supergravity theory any field that acquires a vacuum
expectation value obtains at the same time a non vanishing F-term whose natural
size is given by $<\theta> m_{3/2}$. These F-terms contribute unsuppressed to
the trilinear couplings and have observable effects in the low energy
phenomenology. We show that \mu --> e \gamma decays can receive large
contributions from this source at the level of current experimental bounds.
Therefore this decay may provide the first clue of the structure of the soft
breaking sector with the proposed experiments in the near future.


title: Status of Electroweak Corrections to Top Pair Production

abstract:
  We review the status of electroweak radiative corrections to top-pair
production at a Linear Collider well above the production threshold. We
describe the Fortran package topfit and present numerical results at sqrt(s) =
500 GeV, 1 TeV, and 3 TeV.


title:
Uses of Covariant Formalism for Analytical Computation of Feynman
  Diagrams with Massive Fermions

abstract:
  The bilinear combination of Dirac spinors $u(p_1,n_1)\bar u(p_2,n_2)$ is
expressed in terms of Lorentz vectors in an explicit covariant form. The fact
that the obtained expression involves only one auxiliary vector makes it very
convenient for analytical computations with REDUCE (or FORM) package in the
helicity formalism. The other advantage of the proposed formulas is that they
are applicable to massive fermions as well as to massless fermions. The
proposed approach is employed for the computation of one-loop Feynman diagrams
and it is demonstrated that it considerably reduces the time of computations.


title: Vector Meson Photoproduction in the Soft Dipole Pomeron Model Framework

abstract:
  Exclusive photoproduction of all vector mesons by real and virtual photons is
considered in the Soft Dipole Pomeron model. It is emphasized that being the
Pomeron in this model a double Regge pole with intercept equal to one, we are
led to rising cross-sections but the unitarity bounds are not violated. It is
shown that all available data for $\rho, \omega, \phi, J/\psi $ and $\Upsilon $
in the region of energies 1.7 $\leq W \leq $ 250 GeV and photon virtualities 0
$\leq Q^2 \leq $ 35 GeV$^2$, including the differential cross-sections in the
region of transfer momenta 0 $\leq |t| \leq$ 1.6 GeV$^2$, are well described by
the model.


title: A Note on the J/psi Strong Couplings

abstract:
  In this note we present an evaluation of the couplings JD(*)D(*) and
JD(*)D(*)pi in the Constituent Quark Model. These couplings are a crucial
ingredient in the calculation of cross sections for the processes pi J/psi ->
D(*)Dbar(*), an important background for the J/psi suppression signal in
quark-gluon plasma.


title: Prospects for the Bc Studies at LHCb

abstract:
  We discuss the motivations and perspectives for the studies of the mesons of
the (bc) family at LHCb. The description of production and decays at LHC
energies is given in details. The event yields, detection efficiencies, and
background conditions for several Bc decay modes at LHCb are estimated.


title:
Electromagnetic corrections to $\pi ^-$p scattering length from pionic
  hydrogen

abstract:
  We derive a closed, model space independent, expression for the
electromagnetic correction factor $\delta $ to the scattering length $a$
extracted from a hydrogenic atom with an extended charge to order $\alpha ^2$
and $a^3$ in the limit of a short ranged hadronic interaction.


title: QCD at high energy

abstract:
  I review recent results in QCD at high energy, emphasizing the role of
higher-order computations, power corrections, and Monte Carlo simulations in
the study of a few discrepancies between data and perturbative predictions, and
discussing future prospects.


title: Matching NLO computations and parton showers in QCD

abstract:
  I report on a formalism introduced recently to combine parton shower Monte
Carlo's and next-to-leading order QCD computations.


title: Relativistic quark model and pentaquark spectroscopy

abstract:
  The relativistic five-quark equations are found in the framework of the
dispersion relation technique. The solutions of these equations using the
method based on the extraction of leading singularities of the amplitudes are
obtained. The five-quark amplitudes for the low-lying pentaquarks are
calculated under the condition that flavor SU(3) symmetry holds. The poles of
five-quark amplitudes determine the masses of the lowest pentaquarks. The mass
spectra of pentaquarks which contain only light quarks are calculated. The
calculation of pentaquark amplitudes estimates the contributions of three
subamplitudes. The main contributions to the pentaquark amplitude are
determined by the subamplitudes, which include the meson states.


title:
One-Loop Electroweak Corrections to the Muon Anomalous Magnetic Moment
  Using the Pinch Technique

abstract:
  The definition of the physical properties of particles in perturbative gauge
theories must satisfy gauge invariance as a requisite. The Pinch Technique
provides a framework to define the electromagnetic form factors and the
electromagnetic static properties of fundamental particles in a consistent and
gauge-invariant form. We apply a simple prescription derived in this formalism
to check the calculation of the gauge-invariant one-loop bosonic electroweak
corrections to the muon anomalous magnetic moment.


title: Associated Top Quark-Higgs Boson Production at the LHC

abstract:
  We compute the O(alpha_s^3) inclusive cross section for the process pp ->
t-tbar-h in the Standard Model, at sqrt(s)=14 TeV. The next-to-leading order
corrections drastically reduce the renormalization and factorization scale
dependence of the Born cross section and increase the total cross section for
renormalization and factorization scales larger than m_t. These corrections
have important implications for models of new physics involving the top quark.


title:
Strange vector form factors in the context of the SAMPLE, A4, HAPPEX and
  G0 experiments

abstract:
  We present the recent results of the strange vector form factors of the
nucleon within the framework of the SU(3) chiral quark-soliton model. We
compare our results with the recent experimental data of the SAMPLE and HAPPEX
collaborations and find that they are in a good agreement with the data. We
also predict the future experiments of the A4, HAPPEX-II and G0 collaborations.


title: Two-loop Renormalization Group Equations in General Gauge Field Theories

abstract:
  The complete set of two-loop renormalization group equations in general gauge
field theories is presented. This includes the \beta functions of parameters
with and without a mass dimension.


title: Stop Lepton Associated Production at Hadron Colliders

abstract:
  At hadron colliders, the search for R-parity violating supersymmetry can
probe scalar masses beyond what is covered by pair production processes. We
evaluate the next-to-leading order SUSY-QCD corrections to the associated stop
or sbottom production with a lepton through R-parity violating interactions. We
show that higher order corrections render the theoretical predictions more
stable with respect to variations of the renormalization and factorization
scales and that the total cross section is enhanced by a factor up to 70% at
the Tevatron and 50% at the LHC. We investigate in detail how the heavy
supersymmetric states decouple from the next-to-leading order process, which
gives rise to a theory with an additional scalar leptoquark. In this scenario
the inclusion of higher order QCD corrections increases the Tevatron reach on
leptoquark masses by up to 40 GeV and the LHC reach by up to 200 GeV.


title: A Model for the Color Glass Condensate Versus Jet Quenching

abstract:
  A model for the Color Glass Condensate as opposed to jet quenching is
proposed for the explanation of the presently available RHIC data. Good fits to
these data are presented. A clear way to distinguish between the two possible
explanations is also given.


title: The Nucleon-Nucleon Problem in Quark Models

abstract:
  In the first part we summarize the status of the nucleon-nucleon (NN) problem
in the context of Hamiltonian based constituent quark models and present
results for the l=0 phase shifts obtained from the Goldstone-boson exchange
model by applying the resonationg group method. The second part deals with the
construction of local shallow and deep equivalent potentials based on a
Supersymmetric Quantum Mechanics approach.


title: Deeply Virtual Compton Scattering on Spin-1 Nuclei

abstract:
  We consider the Generalized Parton Distributions for spin-1 nuclei in general
and on the deuteron in particular. We use the impulse approximation to obtain a
convolution model for them. Sum rules are used to check the validity of the
approach and to estimate the importance of higher Fock-space states in the
deuteron. Numerical predictions for the Beam Spin Asymmetry in deeply virtual
Compton scattering are presented.


title:
Nuclear structure corrections in the energy spectra of electronic and
  muonic deuterium

abstract:
  The one-loop nuclear structure corrections of order (Z alpha)^5 to the Lamb
shift and hyperfine splitting of the deuterium are calculated. The contribution
of the deuteron structure effects to the isotope shift (ep)-(ed), (mu p)-(mu d)
in the interval (1S - 2S) is obtained on the basis of modern experimental data
on the deuteron electromagnetic form factors. The comparison with the similar
contributions to the Lamb shift for electronic and muonic hydrogen shows, that
the relative contribution due to the nucleus structure increases when passing
from the hydrogen to the deuterium.


title:
CP violation in decays of the lightest supersymmetric particle with
  bilinearly broken R parity

abstract:
  Supersymmetric models with broken R-parity induced by lepton number violating
terms provide a calculable framework for neutrino masses and mixings. Within
models with bilinear R-parity breaking six new physical phases appear which are
potential sources of novel CP-violating phenomena compared to the minimal
supersymmetric extension of the standard model. We consider CP-violating
observables in the decays of the lightest supersymmetric particle in this class
of models. We show that: (i) Neutrino physics requires a strong correlation
between three different pairs of phases, thus reducing the effective number of
new phases to three. (ii) CP-violating phenomena in decays of the lightest
supersymmetric particle due to new R-parity breaking phases turn out to be
small, once constraints from neutrino physics are taken into account. We
demonstrate that this feature does not depend on the nature of the lightest
supersymmetric particle.


title:
Model independent analysis of 'Lambda' baryon polarizations in (Lambda_b
  -> Lambda l^+ l^-) decay

abstract:
  We present the model independent analysis of $\Lambda$ baryon polarizations
in the (Lambda_b -> Lambda l^+ l^-) decay. The sensitivity of the averaged
'Lambda' polarizations to the new Wilson coefficients is studied. It is
observed that there exist certain regions of the new Wilson coefficients where
the branching ratio coincides with the standard model prediction, while the
'Lambda' baryon polarizations deviate from the standard model results
remarkably.


title:
Consequences of t-channel unitarity for the interaction of real and
  virtual photons at high energies

abstract:
  We analyze the consequences of t-channel unitarity for photon cross sections
and show what assumptions are necessary to allow for the existence of new
singularities at $ Q^{2}=0 $ for the $ \gamma p $ and $ \gamma \gamma $ total
cross sections. For virtual photons, such singularities can in general be
present, but we show that, apart from the perturbative singularity associated
with $ \gamma ^{*}\gamma ^{*}\to q\bar q $, no new ingredient is needed to
reproduce the data from LEP and HERA, in the Regge region.


title:
Three-Body Forces in Multiparticle Dynamics: New Sites of Fundamental
  Dynamics

abstract:
  A manifestation of the three-body forces in multiparticle dynamics is
discussed. The minireview of our recent results has been presented.


title: Pion Structure Function and Violation of the Momentum Sum Rule

abstract:
  We present a method to evaluate the pion structure functions from a box
diagram calculation. Pion and constituent quark fields are coupled through the
simplest pseudoscalar coupling. The gamma^* pi -> q \bar q cross-section is
evaluated and related to the structure functions. We then show that the
introduction of non-perturbative effects, related to the pion size and
preserving gauge invariance, provides us with a straighforward relation with
the quark distribution. It is predicted that higher-twist terms become
negligible for Q^2 larger than about 2 GeV^2 and that quarks in the pion have a
momentum fraction smaller than in the proton. We enlarge the discussion
concerning this violation of the momentum sum rule, emphasizing that the sum
rule is recovered in the chiral limit and also when the finite size condition
is not imposed.


title:
The analytic value of a 3-loop sunrise graph in a particular kinematical
  configuration

abstract:
  We consider the scalar integral associated to the 3-loop sunrise graph with a
massless line, two massive lines of equal mass $M$, a fourth line of mass equal
to $Mx$, and the external invariant timelike and equal to the square of the
fourth mass. We write the differential equation in $x$ satisfied by the
integral, expand it in the continuous dimension $d$ around $d=4$ and solve the
system of the resulting chained differential equations in closed analytic form,
expressing the solutions in terms of Harmonic Polylogarithms. As a byproduct,
we give the limiting values of the coefficients of the $(d-4)$ expansion at
$x=1$ and $x=0$.


title: Analytic Properties of Thermal Corrected Boson Propagators

abstract:
  We investigate the analytic properties of finite-temperature self-energies of
bosons interacting with fermions at one-loop order. A simple boson-fermion
model was chosen due to its interesting features of having two distinct
couplings of bosons with fermions. This leads to a quite different analytic
behavior of the bosons self-energies as the external momentum
$K^{\mu}=(k^{0},\vec{k})$ approaches zero in the two possible limits. It is
shown that the plasmon and Debye masses are consistently obtained at the pole
of the corrected propagator even when the self-energy is analytic at the origin
in the frequency-momentum space.


title: CP violation in chargino decays in the MSSM

abstract:
  In the minimal supersymmetric standard model (MSSM) with complex parameters,
supersymmetric loop effects can lead to \emph{CP} violation. We calculate the
rate asymmetries of decays of charginos into the lightest neutralino and a $W$
boson on the basis of the most important loop contributions in the third
generation squark sectors. It turns out that the \emph{CP} violating
asymmetries can be a few per cent in typical regions of the parameter space of
the MSSM. These processes would provide very promising channels for probing
\emph{CP} violation in the MSSM at future high-energy colliders.


title:
Cross sections and single spin asymmetries in hadronic collisions with
  intrinsic transverse momentum effects

abstract:
  The role of intrinsic transverse momentum both in unpolarized and polarized
processes is discussed. We consider inclusive cross sections for pion
production in hadronic collisions and for Drell-Yan processes; the results are
compared with available experimental data in several different kinematical
situations. We reanalyze transverse single spin asymmetries (SSA) observed in
inclusive pion production, p(transv. polarized) p --> pion + X, in terms of
Sivers effect and show how it can be disentangled in polarized Drell-Yan
processes by suitably integrating over some final configurations. Estimates for
RHIC experiments are given.


title:
The SM Higgs-boson production in gamma gamma -> h -> bb at the Photon
  Collider at TESLA

abstract:
  Measuring the Gamma(h -> gamma gamma)Br(h -> bb) decay at the photon collider
at TESLA is studied for a Standard Model Higgs boson of mass m_h = 120 GeV. The
main background due to the process gamma gamma -> QQ(g), where Q = b,c, is
estimated using the NLO QCD program (G. Jikia); the results obtained are
compared with the LO estimate. Using a realistic luminosity spectrum and
performing a detector simulation, we find that Gamma(h -> gamma gamma)Br(h ->
bb) can be measured with an accuracy better than 2% after one year of photon
collider running.


title: QED Radiative Processes in Deep Inelastic Scattering at HERA

abstract:
  High energy scattering processes of charged particles are accompanied by
radiation of hard photons. Emission collinear to the incident particles, which
leads to a reduction of the effective beam energy, and the possibility to
directly measure these photons at the HERA electron-proton collider provides
important physics opportunities. For deep inelastic scattering, the measurement
of radiative processes extends the kinematic range accessible to the HERA
experiments to lower Q^2, as well as helps in separating the proton structure
functions without the need to run at different collider energies. QED
corrections to these radiative processes are discussed, and the calculation of
the model-independent leptonic corrections is described in some detail for the
complete one-loop contributions as well as for the higher order leading
logarithms.


title:
Covariant tensor formalism for partial wave analyses of psi decay to
  mesons

abstract:
  J/psi and psi' decay to mesons are a good place to look for glueballs,
hybrids and for extracting strange and nonstrange components in mesons.
Abundant J/psi and psi' events have been collected at the Beijing Electron
Positron Collider (BEPC). More data will be collected at upgraded BEPC and
CLEO-C. Here we provide explicit PWA formulae for many interesting channels in
the covariant tensor formalism.


title: Rare Z Decays

abstract:
  Motivated by the well known impact of rare decays of hadrons and leptons on
the evolution of the Standard Model and on limits for new physics, as well as
by the proposal for Giga-Z option at TESLA, we investigate the rare decay Z ->
b s-bar in various extensions of the Standard Model.


title: A model of composite structure of quarks and leptons

abstract:
  In the model every quark or lepton is identified with a quartet of four "more
elementary" particles. One particle in a quartet is a massive spin-0 boson and
other three particles are massless spin-1/2 fermions.


title:
Consistent relativistic Quantum Theory for systems/particles described
  by non-Hermitian Hamiltonians and Lagrangians

abstract:
  A causal, non-Hermitian, renormalizable, local, unitary and Lorentz
convariant formulation of Quantum Theory (QT) (= Quantum Mechanics (QM) and
Quantum Field Theory (QFT)) is developed which is free of formalistic problems
we face in the commonly used Hermitian formulation of QT. Side effects of the
new formulation of QT are the derivation of a consistent (anti)causal neutrino
Lagrangian, the enrichment of chiral symmetries, the removal of the Dirac sea,
the separation of positive and negative energy states including a reformulation
of the anti-particle concept and a critical analysis of the concept of
probability currents. In a first step we apply the new formulation of QT to
establish a relation between perturbative Quantum Chromodynamics (QCD) and the
(axial)vector meson extended Quark-Level Linear Sigma Model (QLLSM) at high
energies.


title: Charting the Higgs Boson Profile e+e- Linear Colliders

abstract:
  The problems of the origin of mass and of electro-weak symmetry breaking are
central to the programme of research in particle physics, at present and in the
coming decades. This paper reviews the potential of high energy, high
luminosity e+e- linear colliders in exploring the Higgs sector,to extend and
complement the data which will become available from hadron colliders. The
accuracy of measurements of the Higgs boson properties will not only probe the
validity of the Higgs mechanism but also provide sensitivity to New Physics
beyond the Standard Model.


title: Absolute Values of Neutrino Masses: Status and Prospects

abstract:
  Compelling evidences in favor of neutrino masses and mixing obtained in the
last years in Super-Kamiokande, SNO, KamLAND and other neutrino experiments
made the physics of massive and mixed neutrinos a frontier field of research in
particle physics and astrophysics. There are many open problems in this new
field. In this review we consider the problem of the absolute values of
neutrino masses, which apparently is the most difficult one from the
experimental point of view. We discuss the present limits and the future
prospects of beta-decay neutrino mass measurements and neutrinoless double-beta
decay. We consider the important problem of the calculation of nuclear matrix
elements of neutrinoless double-beta decay and discuss the possibility to check
the results of different model calculations of the nuclear matrix elements
through their comparison with the experimental data. We discuss the upper bound
of the total mass of neutrinos that was obtained recently from the data of the
2dF Galaxy Redshift Survey and other cosmological data and we discuss future
prospects of the cosmological measurements of the total mass of neutrinos. We
discuss also the possibility to obtain information on neutrino masses from the
observation of the ultra high-energy cosmic rays (beyond the GZK cutoff).
Finally, we review the main aspects of the physics of core-collapse supernovae,
the limits on the absolute values of neutrino masses from the observation of
SN1987A neutrinos and the future prospects of supernova neutrino detection.


title: Noncommutative QED and the Lifetimes of Ortho and Para Positronium

abstract:
  We examine the implications of including corrections associated with the
noncommutative extension of quantum electrodynamics - NCQED - to the decays of
the ortho and para positronium (\Trip and \Sing) ground states. In NCQED, the
well known charge conjugation argument restricting \Trip decays to an odd
number of photons and \Sing decays to an even number of photons no longer
obtains. Instead, the dominant two photon decay mode of \Sing is accompanied by
a three photon mode. The dominant three photon decay mode of \Trip receives a
NCQED correction, but there is no corresponding two photon decay mode in the
weak binding limit. These corrections to the $P_s$ three photon decay mode have
a different energy distribution, but their effect is too small to explain any
discrepancy between the observed and calculated values of the \Trip lifetime.


title: The Phenomenology of Glueball and Hybrid Mesons

abstract:
  The existence of non-q\bar{q} hadrons such as glueballs and hybrids is one of
the most important qualitative questions in QCD. The COMPASS experiment offers
the possibility to unambiguously identify such states and map out the glueball
and hybrid spectrum. In this review I discuss the expected properties of
glueballs and hybrids and how they might be produced and studied by the COMPASS
collaboration.


title: Wolfenstein-like Parametrization of the Neutrino Mixing Matrix

abstract:
  We show that the $3\times 3$ lepton flavor mixing matrix $V$ can be expanded
in powers of a Wolfenstein-like parameter $\Lambda \equiv |V_{\mu 3}| \sim
1/\sqrt{2}$, which measures the strength of flavor conversion in atmospheric
neutrino oscillations. The term of ${\cal O}(\Lambda^2)$ is associated with the
large mixing angle in solar neutrino oscillations. The Dirac phase of CP
violation enters at or below ${\cal O}(\Lambda^8)$, and the Majorana phases of
CP violation are not subject to the $\Lambda$-expansion. Terrestrial matter
effects on this new parametrization in realistic long-baseline neutrino
oscillation experiments are briefly discussed. Some comments are also given on
the possible relation between $\Lambda$ and a relatively weak hierarchy of
neutrino masses.


title:
Threshold configurations in the presence of Lorentz violating dispersion
  relations

abstract:
  A general characterization of lower and upper threshold configurations for
two particle reactions is determined under the assumptions that the single
particle dispersion relations E(p) are rotationally invariant and monotonic in
p, and that energy and momentum are conserved and additive for multiple
particles. It is found that at a threshold the final particle momenta are
always parallel and the initial momenta are always anti-parallel. The
occurrence of new phenomena not occurring in a Lorentz invariant setting, such
as upper thresholds and asymmetric pair production thresholds, is explained,
and an illustrative example is given.


title: Collider Probes of the MSSM Higgs Sector with Explicit CP Violation

abstract:
  We investigate the hadron collider phenomenology of the Minimal
Supersymmetric Standard Model (MSSM) with explicit CP violation for Higgs
bosons that can be observed in Standard Model search channels: W/ZH(->b-bbar)
at the Tevatron, and gg->H(->gamma-gamma), t-tbar-H(->b-bbar) and
WW->H(->tau+tau-) at the LHC. Our numerical analysis is based on a benchmark
scenario proposed earlier called CPX, which has been designed to showcase the
effects of CP violation in the MSSM, and on several variant benchmarks. In most
of the CPX parameter space, these hadron colliders will find one of the neutral
MSSM Higgs bosons. However, there are small regions of parameter space in which
none of the neutral Higgs bosons can be detected in the standard channels at
the Tevatron and the LHC. This occurs because the neutral Higgs boson with the
largest coupling to W and Z bosons decays predominantly into either two lighter
Higgs bosons or a Higgs boson and a gauge boson, whilst the lighter Higgs boson
has only small couplings to the W and Z bosons and the top quark. For other
choices of CP-violating parameters, all three neutral Higgs bosons can have
significant couplings to W and Z bosons, producing overlapping signatures:
these may or may not be distinguishable from backgrounds. The existence of
these regions of parameters provides a strong motivation for a detailed
experimental simulation of these channels.


title: Nuclear modification of transverse-longitudinal structure function ratio

abstract:
  We investigate the nuclear effects on the transverse and longitudinal
responses in the deep inelastic region due to the nuclear binding and nucleon
Fermi motion. We display the role of the transverse-longitudinal admixture due
to the transverse nucleon momentum. The mixing effect is appreciable at small
Q^2 values, and gradually disappears at large Q^2 values. The nuclear
modification is then dominated by the binding and Fermi-motion effects which
are contained in the spectral function.


title:
Recent Muon g-2 Result in Deflected Anomaly-Mediated Supersymmetry
  Breaking

abstract:
  We study the deflected anomaly-mediated supersymmetry breaking (AMSB)
scenario in the light of the recent result of the muon g-2 from Brookhaven E821
experiment. The E821 result suggests the deviation from the SM prediction,
though there remain unsettled uncertainties. We find that the supersymmetric
contribution to the muon g-2 can be \mathcal{O}(10^{-9}), large enough to fill
the deviation, with other experimental constraints satisfied. In particular,
the Higgs mass and b \to s \gamma put severe constraints on the model and large
\tan\beta is favored to enhance the muon g-2.


title: Full two-loop electroweak corrections to the pole masses of gauge bosons

abstract:
  We discuss progress in SM two-loop calculations of the pole position of the
massive gauge-boson propagators.


title:
FIRCLA, one-loop correction to e+ e- to nu anti-nu H and basis of
  Feynman integrals in higher dimensions

abstract:
  An approach for an effective computer evaluation of one-loop multi-leg
diagrams is proposed. It's main feature is the combined use of several systems
- DIANA, FORM and MAPLE. As an application we consider the one-loop correction
to Higgs production in e+ e- to nu anti-nu H, which is important for future e+
e- colliders. To improve the stability of numerical evaluations a non-standard
basis of integrals is introduced by transforming integrals to higher
dimensions.


title: The curvaton scenario in supersymmetric theories

abstract:
  We analyze the curvaton scenario in the context of supersymmety.
Supersymmetric theories contain many scalars, and therefore many curvaton
candidates. To obtain a scale invariant perturbation spectrum, the curvaton
mass should be small during inflation $m \ll H$. This can be achieved by
invoking symmetries, which suppress the soft masses and non-renormalizable
terms in the potential. Other constraints on the curvaton model come from
nucleosynthesis, gravitino overproduction, and thermal evaporation. The
curvaton coupling to matter should be very small to satisfy these constraints
({\it e.g.} $h \lesssim 10^{-8}$ for typical soft masses $m \sim \TeV$).


title: Production and Decay of Excited Electrons at the LHC

abstract:
  We study single production of excited electrons at the CERN LHC through
contact interactions of fermions. Subsequent decays of excited electrons to
ordinary electrons and light fermions via gauge and contact interactions are
examined. The mass range accessible with the ATLAS detector is obtained.


title:
$B \to X_s \gamma$ in minimal supersymmetric standard model with general
  flavor mixing

abstract:
  We present the results of our analysis on $b \to s \gamma$ in the minimal
supersymmetric standard model with a general flavor mixing in the squark
sector. We identify the next--to--leading order focusing effect, which
considerably reduces the gluino contribution to $b \to s \gamma$ relative to
the leading order calculation. We illustrate that $BR(B \to X_s \gamma)$ is
still very sensitive to the flavor mixing parameters, $\delta^d_{ll}$ and
$\delta^d_{lr}$ so that the lower bound for $m_{1/2}$ obtained in the minimal
flavor violation can be easily removed even at $\mu<0$, while it is rather
stable against $\delta^d_{rr}$ and $\delta^d_{rl}$.


title:
Rare decay $B \to X_{s} \nu \bar \nu$ in the two-Higgs-doublet model of
  type-III

abstract:
  In this paper, we calculated the new physics contribution to theoretically
very clean rare decay $B\to X_{s} \nu \bar{\nu}$ in the general
two-Higgs-doublet model (model III). Within the considered parameter space, we
found that (a) the new physics contribution can provide one to two orders of
enhancement to the branching ratio $\calb(B\to X_s \nu \bar{\nu})$ and can
saturate the experimental bound on $\calb(B \to X_s \nu \bar{\nu})$ in some
regions of the parameter space; (b) besides the CLEO data of $B \to X_s
\gamma$, the ALEPH upper limit on $\calb (B \to X_s \nu \bar{\nu})$ also lead
to further constraint on the size of the Yukawa coupling $\lambda_{tt}$:
$\lambda_{tt}< 6.4$ for $\lambda_{bb}=2.7$ and $\mhp=200$ GeV.


title:
Time-Evolution of Collective Meson Fields and Amplification of Quantum
  Meson Modes in Chiral Phase Transition

abstract:
  The time evolution of quantum meson fields in the O(4) linear sigma model is
investigated in a context of the dynamical chiral phase transition. It is shown
that amplitudes of quantum pion modes are amplified due to both mechanisms of a
parametric resonance and a resonance by the forced oscillation according to the
small oscillation of the chiral condensate in the late time of chiral phase
transition.


title: Decoupling and the radiatively-corrected MSSM Higgs sector

abstract:
  In the decoupling limit of a non-minimal Higgs sector, the lightest CP-even
Higgs boson (h) is indistinguishable from the Standard Model (SM) Higgs boson.
In the two-Higgs-doublet sector of the MSSM, the approach to the decoupling
limit (for m_A>>m_Z) persists, even in the presence of potentially large
(tan(beta)-enhanced) radiative corrections to the hbb coupling. Radiative
corrections can also generate an accidental cancellation between tree-level and
one-loop terms, resulting in a SM-like Higgs boson for moderate m_A outside the
decoupling regime.


title: Looking into the Future of Spin and QCD

abstract:
  Several stimulating open questions in high energy spin physics will be
described together with the striking progress recently achieved in this field.
In view of the new experimental facilities and the new tools, soon available, I
will try to anticipate what we will learn next. The prospects for the future
are excellent and clearly, some exciting times are ahead of us.


title:
Electrostatic corrections to the Mikheyev-Smirnov-Wolfenstein potential
  of a neutrino in the sun

abstract:
  This paper is being withdrawn. The electic filed effects should be
interpreted as a correction to the electron density. Therefore the original MSW
potential calculated in terms of the full electron density is correct.


title: Jet physics at hadron colliders

abstract:
  I give a short summary of jet definition algorithms and recent progress in
the quantitative description of jet production.


title: $C^{12}$ shape isomers in the chiral field solitons approach

abstract:
  The variational approach to the problem of seeking axially symmetric solitons
with B=12 is presented. The numerically obtained local minima of the skyrmion
mass functional and baryon charge distributions are pointing to the possible
existence of shape isomers in $C^{12}$ spectra in the the framework of the
original Skyrme model. Theoretical analysis reveals the exclusiveness of each
individual state manifested in the structure of the solitons from the given
topological sector B=12.


title: Lattice QCD for RHIC

abstract:
  I briefly introduce the methods by which lattice QCD predictions for RHIC are
obtained. Next I deal with lattice determinations of strangeness production and
event-to-event fluctuations of conserved quantities. I also present a new
diagrammatic method for computing derivatives with respect to chemical
potentials, and conclude with discussions of some tests of thermal perturbation
theory which follow.


title:
Dispersion relations and Omn\`es representations for $K \to \pi\pi$
  decay amplitudes

abstract:
  We derive dispersion relations for $K\to\pi\pi$ decay, using the
Lehmann-Symanzik-Zimmermann formalism, which allows the analytic continuation
of the amplitudes with respect to the momenta of the external particles. No
off-shell extrapolation of the field operators is assumed. We obtain
generalized Omn\`es representations, which incorporate the $\pi\pi$ and $\pi K$
$S$-wave phase shifts in the elastic region of the direct and crossed channels,
according to Watson theorem. The contribution of the inelastic final-state and
initial-state interactions is parametrized by the technique of conformal
mappings. We compare our results with previous dispersive treatments and
indicate how the formalism can be combined with lattice calculations to yield
physical predictions.


title: Demystifying generalized parton distributions

abstract:
  In this paper, I will explain in as simple and intuitive physical terms as
possible what generalized parton distributions are, what new information about
the structure of hadrons they convey and therefore what picture of the hadron
will emerge. To develop this picture, I will use the example of deeply virtual
Compton scattering (DVCS) and exclusive meson electroproduction processes.
Based on this picture, I will make some general predictions for these
processes.


title:
Baryon inhomogeneity generation via cosmic strings at QCD scale and its
  effects on nucleosynthesis

abstract:
  We have earlier shown that cosmic strings moving through the plasma at the
time of a first order quark-hadron transition in the early universe can
generate large scale baryon inhomogeneities. In this paper, we calculate
detailed structure of these inhomogeneities at the quark-hadron transition. Our
calculations show that the inhomogeneities generated by cosmic string wakes can
strongly affect nucleosynthesis calculations. A comparison with observational
data suggests that such baryon inhomogeneities should not have existed at the
nucleosynthesis epoch. If this disagreement holds with more accurate
observations, then it will lead to the conclusions that cosmic string formation
scales above $10^{14} - 10^{15}$ GeV may not be consistent with nucleosynthesis
and CMBR observations. Alternatively, some other input in our calculation
should be constrained, for example, if the average string velocity remains
sufficiently small so that significant density perturbations are never produced
at the QCD scale, or if strings move ultra-relativistically so that string
wakes are very thin, trapping negligible amount of baryons. Finally, if
quark-hadron transition is not of first order then our calculations do not
apply.


title:
Application of the Large-N_c limit to a Chiral Lagrangian with
  Resonances

abstract:
  It is shown that the implementation of the Large--$N_c$ approximation helps
to get insight into the structure of, in principle, any QCD-like theory. As an
example, we will compute the NLO corrections to $L_{10}$ in the chiral limit
with a Lagrangian with Resonances.


title: Towards High-Precision Predictions for the MSSM Higgs Sector

abstract:
  The status of the evaluation of the MSSM Higgs sector is reviewed. The
phenomenological impact of recently obtained corrections is discussed. In
particular it is shown that the upper bound on m_h within the MSSM is shifted
upwards. Consequently, lower limits on tan beta obtained by confronting the
upper bound as function of tan beta with the lower bound on m_h from Higgs
searches are significantly weakened. Furthermore, the region in the M_A-tan
beta-plane where the coupling of the lightest Higgs boson to down-type fermions
is suppressed is modified. The presently not calculated higher-order
corrections to the Higgs-boson mass matrix are estimated to shift the mass of
the lightest Higgs boson by up to 3 GeV.


title: Parton--Hadron Duality in B Meson Decays

abstract:
  We summarize the current view on Parton-Hadron duality as it applies to B
meson decays. It is emphasized that an OPE treatment is essential for properly
formulating duality and its limitations. Duality violations are unlikely to
become the limiting factor in describing semileptonic B width vis-a-vie higher
order corrections. The consistent extraction of the b quark mass from B
production and decays provides a striking example of the theoretical control
achieved.


title:
Unitarity and Higher-Order Corrections in Neutralino Dark Matter
  Annihilation into Two Photons

abstract:
  The neutralino pair annihilation into two photons in our galactic halo gives
a robust dark matter signal, since it would give a quasi-monotonic gamma ray.
This process is radiatively-induced, and the full-one loop calculation was done
previously. However, for the heavy wino-like or Higgsino-like neutralino, the
one-loop cross section violates unitarity, therefore the higher-order
corrections may be important. We construct a non-relativistic theory for
chargino and neutralino two-body states, and estimate all-order QED corrections
and two-loop corrections by $Z$ and/or $W$ exchange. We find that the critical
mass, above that the two-loop contribution is larger than one-loop one, is
about 8 TeV (O(10) TeV) in the limit where neutralino is wino (Higgsino)-like,
respectively. Around and above the critical mass, the all-order Z and/or W
exchange must be included to estimate the cross section. On the other hand, the
QED corrections depend on the mass difference between the neutralino and
chargino. In the wino-like limit where neutralino is highly degenerate with
chargino in mass, we find that QED corrections enhance the pair annihilation
cross section by 1.5-2.


title: On supersymmetric contributions to the CP asymmetry of the B -> phi K_S

abstract:
  We analyse the CP asymmetry of the B -> phi K_S process in general
supersymmetric models. In the framework of the mass insertion approximation, we
derive model independent limits for the mixing CP asymmetry. We show that
chromomagnetic type of operator may play an important role in accounting for
the deviation of the mixing CP asymmetry between B -> phi K_S and B -> J/psi
K_S processes observed by Belle and BaBar experiments. A possible correlation
between the direct and mixing CP asymmetry is also discussed. Finally, we apply
our result in minimal supergravity model and supersymmetric models with
non-universal soft terms.


title: Incompressibility of strange matter

abstract:
  Strange stars calculated from a realistic equation of state (EOS), that
incorporate chiral symmetry restoration as well as deconfinement at high
density show compact objects in the mass radius curve. We compare our
calculations of incompressibility for this EOS with that of nuclear matter. One
of the nuclear matter EOS has a continuous transition to ud-matter at about
five times normal density. Another nuclear matter EOS incorporates density
dependent coupling constants. From a look at the consequent velocity of sound,
it is found that the transition to ud-matter seems necessary.


title: Probing the transverse spin of quarks in deep inelastic scattering

abstract:
  To identify some way to measure the quark transversity, this thesis analyzes
one-particle and two-particle inclusive deep inelastic scattering, where one
and two of the outgoing hadrons are detected in coincidence with the electron.
It is shown that transversity can be measured in the above processes, in
connection with three different fragmentation functions: the first one requires
the observation of an unpolarized final state hadron with transverse momentum
(Collins function), the second requires the observation of the interference
between the s- and p-wave production of two hadrons, the third requires the
observation of pure p-wave two-hadron production, or equivalently of a spin-one
resonance. All these fragmentation functions fall in the category of T-odd
fragmentation functions: they require the presence of final state interactions,
or else they are forbidden by time-reversal invariance. The last part of the
thesis looks at the possibility of modeling this kind of fragmentation
functions and investigates whether they can be large enough to allow the
extraction of transversity.


title: Instantons at work

abstract:
  The aim of this review is to demonstrate that there exists a coherent picture
of strong interactions, based on instantons. Starting from the first principles
of QCD - via the microscopic mechanism of spontaneous chiral symmetry breaking
- one arrives to a quantitative description of light hadron properties, with no
fitting parameters. The discussion of the importance of instanton-induced
interactions in soft high-energy scattering is new.


title: T-odd quark distributions: QCD versus chiral models

abstract:
  The T-odd quark distrbutions are shown to vanish in the chiral sigma model in
contrast to the opposite widespread opinion. This failure of the chiral sigma
model is a feature of the model itself and has nothing to do with the recent
progress in the clarification of the status of the T-odd distributions in QCD.


title: Grand Unification in RS1

abstract:
  We study unification in the Randall-Sundrum scenario for solving the
hierarchy problem, with gauge fields and fermions in the bulk. We calculate the
one-loop corrected low-energy effective gauge couplings in a unified theory,
broken at the scale M_GUT in the bulk. We find that, although this scenario has
an extra dimension, there is a robust (calculable in the effective field
theory) logarithmic dependence on M_GUT, strongly suggestive of high-scale
unification, very much as in the (4D) Standard Model. Moreover, bulk threshold
effects are naturally small, but volume-enhanced, so that we can accommodate
the measured gauge couplings. We show in detail how excessive proton decay is
forbidden by an extra U(1) bulk gauge symmetry. This mechanism requires us to
further break the unified group using boundary conditions. A 4D dual
interpretation, in the sense of the AdS/CFT correspondence, is provided for all
our results. Our results show that an attractive unification mechanism can
combine with a non-supersymmetric solution to the hierarchy problem.


title: Gauge Model of Quark-Lepton Nonuniversality

abstract:
  We propose a gauge model where quark-lepton universality is an accidental
symmetry which is only approximate, in analogy to the well-accepted notion that
strong isospin is accidental and approximate. This is a natural framework for
explaining possible small deviations of quark-lepton universality which is
applicable to the recently reported apparent nonunitarity of the quark mixing
matrix. As a result, small departures from quark-lepton universality are
expected in Z decays as well as in the recent neutrino data of the NuTeV
collaboration and in future low-energy experiments. New physics is predicted at
the TeV scale.


title:
Generalized distribution amplitudes: new tools to study hadrons'
  structure and interactions

abstract:
  A non-perturbative approach to Generalized Parton Distributions, and to
Deeply Virtual Compton Scattering in particular, based on off mass shell
extension of dual amplitudes with Mandelstam analyticity (DAMA) is developed
with the spin and helicity structure as well as the threshold behavior
accounted for. The model is tested against the data on deep inelastic
electron-proton scattering from JLab.


title: $Z^0$ and W transverse momentum spectra at the LHC

abstract:
  We discuss the transverse momentum distribution of $Z^0$ and $W^\pm$ gauge
bosons at the LHC with $\sqrt s=14$ TeV for pp collisions and with $\sqrt
s=5.5$ TeV for Pb+Pb collisions. Effects of power corrections and shadowing are
also studied.


title: Hadron Colliders, the Standard Model, and Beyond

abstract:
  I argue that the Fermilab Tevatron will contribute to our knowledge of the
pieces of the standard model that we know the least about. I discuss five of
the most important areas in which the Tevatron can confront the standard model:
precision electroweak, CKM, top quark, Higgs, and QCD. I then review the
evidence, both direct and indirect, for physics beyond the standard model.


title: Spin structure of the nucleon at low energies

abstract:
  The spin structure of the nucleon is analyzed in the framework of a
Lorentz-invariant formulation of baryon chiral perturbation theory. The
structure functions of doubly virtual Compton scattering are calculated to
one-loop accuracy (fourth order in the chiral expansion). We discuss the
generalization of the Gerasimov-Drell-Hearn sum rule, the Burkhardt-Cottingham
sum rule and moments of these. We give predictions for the forward and the
longitudinal-transverse spin polarizabilities of the proton and the neutron at
zero and finite photon virtuality. A detailed comparison to results obtained in
heavy baryon chiral perturbation theory is also given.


title:
Direct resummation of the leading renormalons in inclusive semileptonic
  B decay

abstract:
  We present a Borel resummation method for the QCD corrections in inclusive,
charmless, semileptonic B meson decay. The renormalon contributions are
resummed to all orders by employing a bilocal expansion of the Borel transform
that accurately accounts for the first infrared renormalons in the Borel plane.
The renormalons in the pole mass and the QCD expansion are resummed separately,
and a precise relation is obtained between a properly defined pole mass and the
${\bar {\rm MS}}$ mass. The inclusive decay rate is calculated to three loop
order using an estimate of the yet unknown NNLO coefficient.


title: Dynamical Rearrangement of Gauge Symmetry on the Orbifold S^1/Z_2

abstract:
  Gauge theory defined on the orbifold $M^4 \times (S^1/Z_2)$ is investigated
from the viewpoint of the Hosotani mechanism. Rearrangement of gauge symmetry
takes place due to the dynamics of Wilson line phases. The physical symmetry of
the theory, in general, differs from the symmetry of the boundary conditions.
Several sets of boundary conditions having distinct symmetry can be related by
gauge transformations, belonging to the same equivalence class. The Hosotani
mechanism guarantees the same physics in all theories in one equivalent class.
Examples are presented in the SU(5) theory. Zero modes of the extra-dimensional
components, $A_y$, of gauge fields acquire masses by radiative corrections. In
the nonsupersymmetric SU(5) model the presence of bulk fermions leads to the
spontaneous breaking of color SU(3). In the supersymmetric model with
Scherk-Schwarz SUSY breaking zero modes of $A_y$'s acquire masses of order of
the SUSY breaking.


title: An influence functional for ultrasoft QCD

abstract:
  A real-time path integral for ultrasoft QCD is formulated. It exhibits a
Feynman's influence functional. The statistical properties of the theory and
the gauge symmetry are explicit. The correspondence is established with the
alternative version, where a noise term enters a transport equation.


title:
The Higgs Boson Masses of the Complex MSSM: A Complete One-Loop
  Calculation

abstract:
  In the Minimal Supersymmetric Standard Model with complex parameters (cMSSM)
we perform a complete one-loop calculation for the Higgs boson masses
(including the momentum dependence) and the mixing angles. These corrections
are obtained in the Feynman-diagrammatic approach using the on-shell
renormalization scheme. The impact of the newly evaluated corrections is
analyzed numerically. The full one-loop result, supplemented by the leading
two-loop contributions taken over from the real MSSM are implemented into the
public Fortran code FeynHiggs2.0.


title:
Implications on neutrino oscillation plus decay from recent solar
  neutrino data

abstract:
  Recently the Sudbury Neutrino Observatory (SNO) has measured both the rates
as well as the day-night asymmetries in the flux of neutrinos from the Sun in
the charged-current (CC), neutral-current (NC) and elastic scattering (ES)
channels. Motivated by the small but negative day-night asymmetry in the NC
channel at SNO (1.2 standard deviations away from zero), we consider whether
such a non-zero asymmetry can be generated in a framework where active
neutrinos can both oscillate and decay, since the NC day-night asymmetry is
zero in a frame-work that includes pure oscillations of active flavours. We
find that the neutral current day-night asymmetry is strictly zero when we
include both oscillations and decay. The result holds for arbitrary number of
active neutrino species, with some reasonable assumptions on the decay
parameters. Hence, a non-zero asymmetry in the neutral current sector, if it
survives, can only come from oscillations/decay into sterile flavours. We also
examine the allowed region of parameter space coming from a combined analysis
of the total event rates in the charged-current, neutral current and elastic
scattering sectors in a two-flavour framework, and find that the neutral
current rates are most sensitive to (and hence restrict considerably) the
allowed values of the decay parameter involving the life-time of the heavier
mass eigenstate to $\tau_{2_0} > 10^{-4}$ s for eV mass neutrinos.


title: Polarization effects in e^+e^- annihilation processes

abstract:
  We present analytic results for first order radiative QCD corrections to
e^+e^- annihilation processes into quarks and gluons under the special aspect
of polarized final state particles. This aspect involves single-spin
polarization, gluon polarization, and the correlation between quark spins for
massive final state quarks.


title:
A closed analytical formula for two-loop massive tadpoles with arbitrary
  tensor numerators

abstract:
  Using the integration by parts method we derive a closed analytical
expression for the result of the integration of an arbitrary dimensionally
regulated tadpole diagram composed of a massless propagator and two massive
ones, each raised into an arbitrary power, and including an arbitrary tensor
numerator. We also briefly discuss the implementation of the formula in the
algebraic manipulation language of FORM.


title:
The electron-positron annihilation cross section used for high precision
  tests of the Standard Model

abstract:
  Quantities like the fine structure constant at the pole of the Z boson and
the anomalous magnetic moment of the muon are of profound importance for
testing the Standard Model of elementary particle physics. Because these
quantities are known with very high precision, deviations between experimental
measurements and theory predictions for these quantities open a window for
so-called "new physics", i.e. physics beyond the Standard Model. In this
seminar new calculation techniques for the most unreliable part of the theory
predictions, the hadronic contribution, are formulated, discussed and used for
a prediction of these quantities.


title:
Meson resonances from unitarized meson scattering at one loop in Chiral
  Perturbation Theory

abstract:
  We show the results for the scattering poles associated to the rho, f0, a0,
K*, sigma and kappa resonances in meson-meson scattering. Our amplitudes are
obtained from the complete one-loop meson-meson scattering amplitudes from
Chiral Perturbation Theory. Once unitarized with the Inverse Amplitude Method,
they describe remarkably well the data simultaneously in the low energy and
resonance regions up to 1.2 GeV, using low energy parameters compatible with
present determinations.


title: The F/D Ratio and Meson-Baryon Couplings from QCD Sum Rules

abstract:
  Coupling constants of the pseudoscalar mesons to the octet baryons are
computed in the QCD sum rule approach. The pi-NN, eta-NN, pi-XiXi, eta-XiXi,
pi-SigmaSigma, eta-SigmaSigma as well as pi-Lambda-Sigma couplings are studied.
Determining the pertinent Dirac structure in the correlation function, we
analyze the couplings in the SU(3) limit. We find the F/D ratio to be \sim
0.6-0.8 that is consistent with the SU(6) value. We also estimate the SU(3)
breaking effect using a projected correlation function method.


title: The chirally-odd twist-3 distribution e(x)

abstract:
  Properties of the nucleon twist-3 distribution function e(x) are reviewed. It
is emphasized that the QCD equations of motion imply the existence of a
delta-function at x=0 in e(x), which gives rise to the pion-nucleon sigma-term.
According to the resulting ``practical'' DIS sum rules the first and the second
moment of e(x) vanish, a situation analogue to that of the pure twist-3
distribution function $\bar{g}_2(x)$.


title:
Scalar and Tensor Force Contribution to the Nucleon-Nucleon Interaction
  Within a Chiral Constituent Quark Model

abstract:
  The nucleon-nucleon problem is studied as a six-quark system in a
nonrelativistic chiral constituent quark model where the Hamiltonian contains a
linear confinement and a pseudoscalar meson (Goldstone boson) exchange
interaction between the quarks. This hyperfine interaction has a long-range
Yukawa-type part, depending on the mass of the exchanged meson and a
short-range part, mainly responsible for the good description of the baryon
spectra.


title: Parton Percolation in Nuclear Collisions

abstract:
  An essential prerequisite for quark-gluon plasma production in nuclear
collisions is cross-talk between the partons from different nucleons in the
colliding nuclei. The initial density of partons is determined by the parton
distribution functions obtained from deep inelastic lepton-hadron scattering
and by the nuclear geometry; it increases with increasing $A$ and/or $\sqrt s$.
In the transverse collision plane, this results in clusters of overlapping
partons, and at some critical density, the cluster size suddenly reaches the
size of the system. The onset of large-scale cross-talk through color
connection thus occurs as geometric critical behavior. Percolation theory
specifies the details of this transition, which leads to the formation of a
condensate of deconfined partons. Given sufficient time, this condensate could
eventually thermalize. However, already the onset of parton condensation in the
initial state, without subsequent thermalization, leads to a number of
interesting observable consequences.


title: Effects of Universal Extra Dimensions on $B^0 - {\bar B^0}$ Mixing

abstract:
  We study contributions coming to $\Delta m_B$ from one or more universal
extra dimensions (UED) in which all the Standard Model fields can propagate. In
the model with a single UED, the box diagrams for mixing are convergent and
therefore insensitive to the cutoff scale of the theory. In the case of two
UEDs, the result is not very sensitive to the cut-off scale due to GIM
mechanism. Within the present range of the parameters at $1 \sigma$ level, the
lower bound on the compactification scale 1/R has been estimated to be 165 GeV
for one UED and 280 GeV for two UEDs. The bound increases drastically if one
can have a better determination of the $B$ meson decay constant $f_B$ and the
QCD correction parameter $B_B$. For example, it rises to 740 GeV (for one UED)
if the error (at $1\sigma$) in the determination of $f_B\sqrt{B_B}$ from
quenched lattice calculation is reduced to one-third from its present value.
The UED contributions to the $K$ system are strongly suppressed.


title: More about the Standard Model at Intersecting Branes

abstract:
  Intersecting D-brane models seem to be one of the most promising avenues to
embed the Standard Model physics within the string context. We review here
different aspects of these models. Topics include the question of SUSY and
quasi-SUSY in intersecting brane models, model-building, the brane
recombination interpretation of the SM Higgs mechanism, Yukawa couplings, the
lowering of the string scale and possible new Z's accessible to accelerators.


title: Solar neutrino oscillations with electrostatic corrections

abstract: This paper is being withdrawn.


title: CP violation in supersymmetric theories

abstract:
  We review the present status of CP violating problem in supersymmetric
extensions of the standard model. We analyze the constraints imposed by the
experimental limits of the electron, neutron, and mercury electric dipole
moments on the supersymmetric CP phases and show that only the scenarios with
flavour-off- diagonal CP violation remain attractive. These scenarios require
hermitian Yukawa matrices which naturally arise in models with left-right
symmetry or a SU(3) flavour symmetry. In this case, epsilon_K and
epsilon'/epsilon can be saturated by a small non-universality of the soft
scalar masses through the gluino and chargino contributions respectively. The
model also predicts a strong correlation between A_{CP}(b-> s gamma) and the
neutron electric dipole moment. In this framework, the standard model gives a
the leading contribution to the CP asymmetry in B ->psi K_S decay, while the
dominant chargino contribution to this asymmetry is < 0.2. Thus, no constraint
is set on the non-universality of this model by the recent BaBar and Belle
measureets.


title:
Possible improvements on the mass of the tau neutrino using leptonic
  $D^\pm_s$ decays

abstract:
  We show how a very accurate measurement of the branching ratios of the
leptonic decay modes of the $D^\pm_s$ mesons can lead to a significant
improvement in the mass limit for the tau neutrino.


title: Photon-jet correlation in heavy ion collisions at the LHC

abstract:
  Transverse momentum imbalance between a jet produced with a hard photon is
considered as a signal of medium-induced partonic energy loss in
ultrarelativistic heavy ion collisions. We analyze photon-jet correlation in
the context of a real experimental situation at the LHC, the problem of neutral
pion background being discussed.


title:
Rapidity and Transverse Momentum Distributions of DIS 1-jet Inclusive
  Cross Section -- A Next-to-Leading Order Monte-Carlo Prediction

abstract:
  We have implemented in the RAPGAP program a previously derived subtraction
method for next-to-leading order (NLO) corrections in Monte-Carlo event
generators, and we show results for jet production in deep inelastic
scattering. At small x_{bj}, NLO corrections are comparable to the LO cross
section, because of the large gluon density. We devise a jet observable that is
particularly sensitive to the treatment of parton kinematics, which our method
is intended to treat correctly. We compare the results of the calculation with
LO calculations and with the previously existing treatment of NLO processes in
RAPGAP. Substantial corrections to the event distribution are found.


title:
Super-Kamiokande hep neutrino best fit: a possible signal of
  nonmaxwellian solar plasma

abstract:
  The Super-Kamiokande best global fit, which includes data from SNO, Gallium
and Chlorine experiments, results in a hep neutrino contribution to the signals
that, even after oscillation, is greater than the SSM prediction. The solar hep
neutrino flux that would yield this contribution is four times larger than the
one predicted by the SSM. Recent detailed calculations exclude that the
astrophysical factor S_{hep}(0) could be wrong by such a large factor. Given
the reliability of the temperature and densities profiles inside the Sun, this
experimental result indicates that plasma effects are important for this
reaction. We show that a slight enhancement of the high-energy tail,
enhancement that is of the order of the deviations from the Maxwell-Boltzmann
distribution expected in the solar core plasma, produces an increment of the
hep rate of the magnitude required. We verified that the other neutrino fluxes
remain compatible with experimental signals and SSM predictions. Better
measurements of the high-energy tail of the neutrino spectrum would improve our
understanding of reaction rates in the solar plasma.


title: Rapidity distribution of jet quenching: effects on global observables

abstract:
  We discuss modification in the rapidity distribution of the transverse energy
flow as a signal of medium-induced partonic energy loss in ultrarelativistic
heavy ion collisions. A scan of the global energy flow and jet rates in the
wide rapidity region might provide the important information about the
pseudo-rapidity size of a dense medium created in heavy ion collisions at the
LHC.


title: Meson model for f_0(980) production in peripheral pion-nucleon reactions

abstract:
  The Juelich model for pion-pion-scattering, based on an effective meson-meson
Lagrangian is applied to the analysis of the S-wave production amplitudes
derived from the BNL E852 experiment pi^- p -> pi^0 pi^0 n for a pion momentum
of 18.3 GeV. The unexpected strong dependence of the S-wave partial wave
amplitude on the momentum transfer between the proton and neutron in the
vicinity of the f_0(980) resonance is explained in our analysis as interference
effect between the correlated and uncorrelated pi^0 pi^0 pairs.


title: Hierarchy plus anarchy in quark masses and mixings

abstract:
  We introduce a new parameterisation of the effect of unknown corrections from
new physics on quark and lepton mass matrices. This parameterisation is used in
order to study how the hierarchies of quark masses and mixing angles are
modified by random perturbations of the Yukawa matrices. We discuss several
examples of flavour relations predicted by different textures, analysing how
these relations are influenced by the random perturbations. We also comment on
the unlikely possibility that unknown corrections contribute significantly to
the hierarchy of masses and mixings.


title: Two-loop Neutrino Mass Generation and its Experimental Consequences

abstract:
  If neutrino masses have a radiative origin, their smallness can be naturally
understood even when lepton number violation occurs near the weak scale. We
analyze a specific model of this type wherein the neutrino masses arise as
two--loop radiative corrections. We show that the model admits the near
bimaximal mixing pattern suggested by the current neutrino oscillation data.
Unlike the conventional seesaw models, these two--loop models can be directly
tested in lepton flavor violating decays tau -> 3 mu and mu -> e + gamma as
well as at colliders by the direct observation of charged scalars needed for
the mass generation. It is shown that consistency with the neutrino oscillation
data requires that the leptonic rare decays should be within reach of
forthcoming experiments and that the charged scalars are likely to be within
reach of the LHC.


title: R-Parity violation in B --> pi+ pi- decay

abstract:
  We consider the impact of R-parity violating suprsymmetry in the nonleptonic
decay B --> pi+ pi-. This is one of the rare instances where new physics
contributes to both B-Bbar mixing and B --> pi+ pi- decay. We do a numerical
analysis to capture the interplay between these two effects and place
constraints on the relevant parameter space.


title: The Form Factors of omega pi0 and pi+ pi- at psi(2S)

abstract:
  The measurements of psi(2S) -> omega pi0 and psi(2S) -> pi+ pi- in e+e-
experiments are examined. It is found that the non-resonance virtual photon
annihilation gives large contributions to the observed cross sections of these
two processes. By including this contribution, the form factors and branching
fractions of these two decay modes are revised.


title: Jet quenching and high-pt azimuthal asymmetry

abstract:
  The azimuthal anisotropy of high-pt particle production in non-central heavy
ion collisions is among the most promising observables of partonic energy loss
in an azimuthally non-symmetric volume of quark-gluon plasma. We discuss the
implications of nuclear geometry for the models of partonic energy loss in the
context of recent RHIC data and consequences for observation of jet quenching
at the LHC.


title:
Influence of the Sommerfeld Corrections to the Electric Polarizability
  of the Pion

abstract:
  The valence-quark contribution to the electric polarizability of the pion in
a semirelativistic description is shown to be smaller than its nonrelativistic
limit.


title:
Hadronic production of light color-triplet Higgs bosons: an alternative
  signature for GUT

abstract:
  The conventional signature for grand unified theories (GUT) is the proton
decay. Recently, some models in extra dimensions or with specific discrete
symmetries, which aim at solving the doublet-triplet problem, allow the
color-triplet in the TeV mass region by suppressing the Yukawa couplings of the
triplets to matter fermions. We study the hadronic production and detection of
these TeV colored Higgs bosons as an alternative signature for GUT, which would
behave like massive stable charged particles in particle detectors producing a
striking signature of a charged track in the central tracking system and being
ionized in the outer muon chamber. We found that the LHC is sensitive to a
colored Higgs boson up to about 1.5 TeV. If the color-triplets are stable in
cosmological time scale, they may constitute an interesting fraction of the
dark matter.


title: Towards a theory of quark masses, mixings and CP-violation

abstract:
  We discuss the structure of Yukawa couplings in D-brane models in which the
SM fermion spectrum appears at the intersections of D-branes wrapping a compact
space. In simple toroidal realistic examples one can explicitly compute the
Yukawa couplings as a function of the geometrical data summing over world-sheet
instanton contributions. A particular simple model with a N = 1 SUSY spectrum
and three quark-lepton generations is studied in some detail. Remarkably, one
can reproduce the observed spectrum of quark masses and mixings for particular
choices of the compact radii and brane locations. In order to reproduce the
smallness of up- and down-quark masses branes should be located in simple
geometric configurations leading to some accidental global symmetries. We also
find that the brane configurations able to reproduce the observed data may be
considered as a deformation (by brane translation) of a configuration with
Pati-Salam gauge symmetry. The origin of CP-violation in this formalism is
quite elegant. It appears as a consequence of the generic presence of U(1)
Wilson line backgrounds in the compact dimensions. One can reproduce the
observed results for the CP-violation Jarlskog invariant J as long as the
compact radii are of order of the string scale.
  DISCLAIMER: This paper is going to be substantially revised. Althought the
physics and general concepts are still valid, the Yukawa couplings of the
particular model presented in this paper have a simpler form than discussed
here, as we recently pointed out in hep-th/0302105. A properly revised version
will be eventually sent as the paper is appropriately corrected.


title: Broken unitarity of the SM and a new theory of EW interactions

abstract:
  It shows that because of the axial-vector coupling and the coupling with
fermions of different masses the untarity of the SM is broken at the scale of
10^{14}GeV. A new theory of EW interactions without Higgs is proposed. We
obtain M^2_W=g^2 m^2_t/2, M^2_Z=(g^2+g'^2)m^2_t/2, and G_F=1/(2\sqrt{2}m^2_t}.


title: Hard Exclusive Baryon-Antibaryon Production in Two-Photon Collisions

abstract:
  We study baryon pair production in two-photon collisions, gamma gamma -> B
Bbar, within perturbative quantum chromodynamics, treating baryons as
quark-diquark systems. We extend previous work within the same approach by
treating constituent-mass effects systematically by means of an expansion in
the small parameter (mass/photon energy). Our approach enables us to give a
consistent description of the cross sections for all octet baryon channels.
Adopting the model parameters from foregoing work, we are able to reproduce the
most recent large-momentum-transfer data from LEP for the p pbar, Lambda
Lambdabar, and Sigma^0 Sigma^0bar channels in a quite satisfactory way. We also
briefly address the crossed process for the proton channel, gamma p -> gamma p.


title:
Diffractive \eta_c and \eta_b productions by neutrinos via neutral
  currents

abstract:
  We report a first theoretical study for neutrino-induced diffractive
productions of heavy pseudoscalar mesons, \eta_c and \eta_b, off a nucleon.
Based on factorization formalism for exclusive processes, we evaluate the
forward diffractive production cross section in perturbative QCD in terms of
the light-cone Q\bar{Q} wave functions (WFs) of \eta_{c,b} mesons and the gluon
distribution of the nucleon. The light-cone WFs of the \eta_c (\eta_b) meson
are constructed to satisfy the spin symmetry relations with those of the J/\psi
(\Upsilon) meson. The diffractive \eta_c production is governed by the
axial-vector coupling of the longitudinally polarized Z boson to Q\bar{Q} pair,
and the resulting \eta_c production rate is larger than the J/\psi one by one
order of magnitude. We also discuss the production of bottomonium \eta_b, which
shows up for higher beam energy.


title: Two-Loop Results for M_W in the Standard Model and the MSSM

abstract:
  Recent higher-order results for the prediction of the W-boson mass, M_W,
within the Standard Model are reviewed and an estimate of the remaining
theoretical uncertainties of the electroweak precision observables is given. An
updated version of a simple numerical parameterisation of the result for M_W is
presented. Furthermore, leading electroweak two-loop contributions to the
precision observables within the MSSM are discussed.


title: The Accelerated Universe and the Moon

abstract:
  Cosmologically motivated theories that explain small acceleration rate of the
Universe via modification of gravity at very large, horizon or super-horizon
distances, can be tested by precision gravitational measurements at much
shorter scales, such as the Earth-Moon distance. Contrary to the naive
expectation the predicted corrections to the Einsteinian metric near
gravitating sources are so significant that fall within sensitivity of the
proposed Lunar Ranging experiments. The key reason for such corrections is the
van Dam-Veltman-Zakharov discontinuity present in linearized versions of all
such theories, and its subsequent absence at the non-linear level ala
Vainshtein.