title: Global event properties in proton-proton physics with ALICE

abstract:
  ALICE is a unique opportunity for studying low Pt physics and minimum bias
events, and consequently for hunting substructures in strong interactions. The
general question concerning global event properties in pp and ppbar physics is
indeed whether substructures can be seen in the data in a model-independent
way. In other terms, can we identify the interface between perturbative and
non-perturbative regimes?


title: Correlations in proton-proton collisions with ALICE

abstract:
  Particle correlations and particle multiplicity distributions cannot be
approached independently: a unified description of correlations and
multiplicity distributions is always needed in order to understand the
underlying dynamics in high energy collisions. In this light, we review the
most recent and interesting results on rapidity and momentum correlations,
emphasising the possibilities of measurements with the ALICE detector.


title:
Spin polarization and the Einstein--Podolsky--Rosen paradox in the Monte
  Carlo event records

abstract:
  In the future high energy physics experiments, the question of properly
matching the phenomenological programs that describe different parts of the
physics processes (such as hard scattering, hadronization, decay of resonances,
detector response, etc.) is very important. In the past, FORTAN common blocks
filled with lists of objects (particles, strings, clusters, etc.) of defined
properties, origins and descendants were in use. Similar structures are now
envisaged, for future programs, to be written in languages such as C++ or Java.
  From the physics point of view such an approach is not correct, since this
kind of data structures impose certain approximations on the physics content.
In the present paper, we will explore their limits, using examples from the
physics of W's, tau's and the Higgs boson, still to be discovered.


title:
Non-perturbative gluon evolution, squeezing, correlations and chaos in
  jets

abstract:
  We study evolution of colour gluon states in isolated QCD jet at the
non-perturbative stage. Fluctuations of gluons are less than those for coherent
states under specific conditions. This fact suggests that there gluon squeezed
states can arise. The angular and rapidity dependencies of the normalized
second-order correlation function for present gluon states are studied at this
stage of jet evolution. It is shown that these new gluon states can have both
sub-Poissonian and super-Poissonian statistics corresponding to, respectively,
antibunching and bunching of gluons by analogy with squeezed photon states.
  We investigate the possibility of coexisting both squeezing and chaos using
Toda criterion and temporal correlator analysis. It is shown that these effects
may coexist under some conditions.


title: Studies in Topics Going beyond the Standard Electroweak Model

abstract:
  Supersymmetric Standard Model has been built to solve the hierarchy problem
which is encountered whenever Standard Model is incorporated into a theory with
a larger mass scale. Experimentally, one of the first signals of physics beyond
Standard Model is provided by the atmospheric neutrino experiments which
indicate the existence of at least one non-zero neutrino mass. An
interpretation of both solar and atmospheric neutrino anomalies in terms of
neutrino oscillations would lead to specific patterns for neutrino masses and
mixing. In this thesis, we studied the possibilities of generating the required
neutrino mass patterns in the context of supersymmetric standard models with
lepton number (L) violation. After an introduction to supersymmetric standard
models in Chapter 1, we give an overview of neutrino phenomenology in chapter
2. Chapter 3 discusses analytical and semi-analytical solutions to
Renormalisation Group Equations (RGE) with lepton number violating couplings in
the superpotential. Neutrino masses with bilinear L violation in the context of
gauge mediated supersymmetric models (GMSB) are discussed in Chapter 4, where
2-loop RGE for the parameter $\Delta B_i$ are presented. Chapter 5 discusses
neutrino mass structure when L violation is through trilinear lepton number
violating terms. Chapter 6 discusses RG enhancement of neutrino masses and
neutrino mass bounds on trilinear lepton number violating couplings in the
context of mSUGRA. Chapter 7 summarises general features of neutrino masses
within these models and contains overall conclusions based on the work
presented in the thesis.


title:
One-loop corrections to the process e+ e- -> t tbar including hard
  bremsstrahlung

abstract:
  Radiative corrections to the process e+ e- to t tbar are calculated in
one-loop approximation of the Standard Model. There exist results from several
groups. This talk provides further comparisons of the complete elektroweak
contributions, including hard bremsstrahlung. The excellent final agreement of
the different groups allows to continue by working on a code for an event
generator for TESLA and an extension to e+ e- to 6 fermions.


title: On Axion Thermalization in the Early Universe

abstract:
  We reanalyze the conditions under which we have a primordial thermal
population of axions. Compared with previous studies, we find other processes,
involving gluons and quarks, that dominate at high temperatures. We conclude
that if the Peccei-Quinn scale fulfills $F_a < 1.2 \times 10^{12} \GeV$ there
is thermal axion production. In this case, a period in the early universe
exists where axions interact with the QCD plasma and we point out that
non-thermal axions produced before the end of this period will thermalize. This
could lead to a reduction of the expected density of axions from string decay
in models with $F_a < 1.2 \times 10^{12} \GeV$.


title: Stable Bimaximal neutrino mixing pattern

abstract:
  The neutrino oscillation experiments increasingly point towards a mixing
pattern that can be parametrised with two near maximal and one small mixing
angle. We investigate whether such a mixing pattern can be generated as a fixed
point of renormalisation group evolution.


title: Calculable Corrections to Brane Black Hole Decay I: The Scalar Case

abstract:
  In the context of brane-world theories, the production cross-section for
black holes may be greatly enhanced. Such black holes can in principle lead to
detectable signals via their Hawking evaporation to brane-localized modes. We
calculate, in the semiclassical approximation, the leading corrections to the
energy spectrum (the greybody factors) for decay into scalar fields, as a
function of the number of toroidally compactified extra dimensions, and partial
wave number.


title:
Simple Formulae for Sin^2 theta_eff^lept, M_W, Gamma_l, and their
  Physical Applications

abstract:
  The calculation of the partial widths of the Z boson in the effective scheme
is discussed. Simple formulae for Sin^2 theta_eff^lept, M_W, and Gamma_l in the
on-shell, MS, and effective renormalization schemes are presented. Their domain
of validity extends to low M_H values probed by current experiments, and to the
range of Delta alpha_hadr results from recent calculations. Physical
applications of these formulae are illustrated. A comparative analysis of the
above mentioned schemes is presented. The paper includes a discussion of the
discrepancy of the Sin^2 theta_eff^lept values derived from the leptonic and
hadronic sectors and of the shortcomings of theoretical error estimates of
Sin^2 theta_eff^lept based solely on those affecting M_W.


title: Semileptonic D decay into scalar mesons: a QCD sum rule approach

abstract:
  Semileptonic decays of D-mesons into scalar hadronic states are investigated.
Two extreme cases are considered: a) the meson decays directly into an
uncorrelated scalar state of two two mesons and b) the decay proceeds via
resonance formation. QCD sum rules including instanton contributions are used
to calculate total and differential decay rates under the two assumptions.


title:
Constraints of mixing matrix elements in the sequential fourthgeneration
  model

abstract:
  We review our works on the sequential fourth generation model and focus on
the constriants of $4\times 4$ quark mixing matrix elements. We investigate the
quark mixing matrix elements from the rare $K,B$ meson decays. We talk about
the $ hierarchy$ of the $4\times 4$ matrix and the existence of fourth
generation.


title: Polarized triplet production by circularly polarized photons

abstract:
  A process of the pair production by a circularly polarized photon in the
field of unpolarized atomic electron has been considered in the
Weizaecker-Williams approximation. The degree of longitudinal polarization of
positron and electron has been calculated. An exclusive cross-section as well
as a spectral distribution are obtained. We estimate the accuracy of our
calculations at the level of a few percent. We show the identity of the
positron polarization for considered process and for process of pair production
in the screened Coulomb field of nucleus.


title: Quantum Instability for Mixed States

abstract:
  The analysis of the time evolution of unstable states which are linear
superposition of other, observable, states can, in principle, be carried out in
two distinct, non-equivalent ways. One of the methods, usually employed for the
neutral kaon system, combines the mixing and instability into one single step
which then results into unconventional properties of the mass-eigenstates. An
alternative method is to remain within the framework of a Lagrangian formalism
and to perform the mixing prior to the instability analysis. Staying close to
the $K^0-\bar{K^0}$ system, we compare both methods pointing out some of their
shortcomings and advantages.


title:
Executive Summary of the Snowmass 2001 Working Group (P1) ``Electroweak
  Symmetry Breaking''

abstract:
  In this summary report of the 2001 Snowmass Electroweak Symmetry Breaking
Working Group, the main candidates for theories of electroweak symmetry
breaking are surveyed, and the criteria for distinguishing among the different
approaches are discussed. The potential for observing electroweak symmetry
breaking phenomena at the upgraded Tevatron and the LHC is described. We
emphasize the importance of a high-luminosity $e^+e^-$ linear collider for
precision measurements to clarify the underlying electroweak symmetry breaking
dynamics. Finally, we note the possible roles of the $\mu^+\mu^-$ collider and
VLHC for further elucidating the physics of electroweak symmetry breaking.


title:
Radiation defects in silicon due to hadrons and leptons, their annealing
  and influence on detector performance

abstract:
  A phenomenological model was developed to explain quantitatively, without
free parameters, the production of primary defects in silicon after particle
irradiation, the kinetics of their evolution toward equilibrium and their
influence on detector parameters. The type of the projectile particle and its
energy is considered in the evaluation of the concentration of primary defects.
Vacancy-interstitial annihilation, interstitial migration to sinks, vacancy -
impurity complexes (VP, VO, V2O), and divacancy (V2) formation are taken into
account in different irradiation conditions, for different concentrations of
impurities in the semiconductor material, for 20 and 0 degrees C. The model can
be extended to include other vacancy and interstitial complexes. The density of
the reverse current in the detector after irradiation is estimated. Comparison
with experimental measurements is performed. A special application considered
in the paper is the modelled case of the behaviour of silicon detectors
operating in the pion field estimated for the LHC accelerator, under continuum
generation and annealing.


title: Summary of Photon 2001

abstract:
  This article summarizes the experimental and theoretical results presented
and discussed at the International Conference on the Structure and Interactions
of the Photon, PHOTON 2001, in Ascona.


title: Measurement of the branching fraction for the decay KS --> pi e nu

abstract:
  We present a measurement of the branching ratio BR(KS --> pi e nu) performed
using the KLOE detector. KS mesons are produced in the reaction e+ e- --> phi
--> KS KL at the DAFNE collider. In a sample of about 5 million KS-tagged
events we find 624 +- 30 semileptonic KS decays. Normalizing to the KS --> pi+
pi- count in the same data sample, we obtain BR(KS --> pi e nu) = (6.91 +-
0.37) 10^-4, in agreement with the Standard Model expectation.


title: Neutrino Mass Matrix Running for Non-Degenerate See-Saw Scales

abstract:
  We consider the running of the neutrino mass matrix in the Standard Model and
the Minimal Supersymmetric Standard Model, extended by heavy singlet Majorana
neutrinos. Unlike previous studies, we do not assume that all of the heavy mass
eigenvalues are degenerate. This leads to various effective theories when the
heavy degrees of freedom are integrated out successively. We calculate the
Renormalization Group Equations that govern the evolution of the neutrino mass
matrix in these effective theories. We show that an appropriate treatment of
the singlet mass scales can yield a substantially different result compared to
integrating out the singlets at a common intermediate scale.


title: Photon Scattering by Negative Energy Electrons

abstract: This paper has been withdrawn due to an error in section 3.


title: Status of Spin Physics - Experimental Summary

abstract:
  The current status of spin physics experiments, based on talks presented at
the Third Circum-Pan-Pacific Symposium on High Energy Spin Physics held in
Beijing, 2001, is summarized in this article. Highlights of recent experimental
results at SLAC, JLab, and DESY, as well as future plans at these facilities
and at RHIC-spin are discussed.


title: Perturbative QCD with Quark and Gluon Condensates

abstract:
  QCD perturbation theory using quark and gluon propagators that have an extra
term at zero four-momentum is equivalent to standard PQCD in the presence of
massless quark and gluon pairs in the perturbative vacuum. We verify at low
orders in perturbation theory that $<\bar\psi\psi> \neq 0$ and that quarks
acquire a constituent mass. Thus chiral symmetry is spontaneously broken, and
the conservation of the axial vector current ensures a massless pion. The gluon
pairs generate an $<F_{\mu\nu}F^{\mu\nu}>$ expectation value and a tachyonic
gluon mass. Lorentz and gauge symmetry is preserved, and the short-distance
structure of PQCD is unaffected. The modified perturbative expansion thus
contains relevant elements of QCD at both short and long distances.


title: Minimal Schemes for Large Neutrino Mixings with Inverted Hierarchy

abstract:
  Existing oscillation data point to nonzero neutrino masses with large
mixings. We analyze the generic features of the neutrino Majorana mass matrix
with inverted hierarchy and construct realistic {\it minimal schemes} for the
neutrino mass matrix that can explain the large (but not maximal) \nu_e -
\nu_mu mixing of MSW-LAM as well as the nearly maximal \nu_mu - \nu_tau mixing
and the small (or negligible) \nu_e --> \nu_tau transition. These minimal
schemes are quite unique and turn out to be extremely predictive. Implications
for neutrinoless double beta decay, tritium beta decay and cosmology are
analyzed.


title: Quark Mass Matrices in the A_4 Model

abstract:
  If the standard model of quark interactions is supplemented by a discrete A_4
symmetry (which may be relevant for the lepton sector), the spontaneous
breaking of the electroweak gauge symmetry allows arbitrary quark masses, but
all mixing angles are predicted to be zero. A pattern of the explicit breaking
of A_4 is proposed, which results in a realistic charged-current mixing matrix.


title:
Measuring High Energy Neutrino-Nucleon Cross Sections With Future
  Neutrino Telescopes

abstract:
  Next generation kilometer-scale neutrino telescopes, such as ICECUBE, can
test standard model predictions for neutrino-nucleon cross sections at energies
well beyond the reach of collider experiments. At energies near a PeV and
higher, the Earth becomes opaque to neutrinos. At these energies, the ratio of
upgoing and downgoing events can be used to measure the total neutrino-nucleon
cross section given the presence of an adequate high energy neutrino flux.


title: Signals for Noncommutative QED at Future $e^+e^-$ Colliders

abstract:
  The signatures for noncommutative QED at $e^+e^-$ colliders with center of
mass energies in the range of 0.5-5 TeV are examined. For integrated
luminosities of 0.5-1 ab$^{-1}$ or more, sensitivities to the associated mass
scales greater than $\sqrt s$ are possible.


title:
Constraints on possible phase transitions above the nuclear saturation
  density

abstract:
  We compare different models for hadronic and quark phases of cold baryon-rich
matter in an attempt to find a deconfinement phase transition between them. For
the hadronic phase we consider Walecka-type mean-field models which describe
well the nuclear saturation properties. We also use the variational chain model
which takes into account correlation effects. For the quark phase we consider
the MIT bag model, the Nambu-Jona-Lasinio and the massive quasiparticle models.
By comparing pressure as a function of baryon chemical potential we find that
crossings of hadronic and quark branches are possible only in some exceptional
cases while for most realistic parameter sets these branches do not cross at
all. Moreover, the chiral phase transition, often discussed within the
framework of QCD motivated models, lies in the region where the quark phases
are unstable with respect to the hadronic phase. We discuss possible physical
consequences of these findings.


title:
Effect of the galactic halo modeling on the DAMA/NaI annual modulation
  result: an extended analysis of the data for WIMPs with a purely
  spin-independent coupling

abstract:
  The DAMA/NaI Collaboration has observed a 4-sigma C.L. model independent
effect investigating the annual modulation signature in the counting rate of an
NaI(Tl) set-up (total exposure of 57986 kg day) and the implications of this
effect have been studied under different model-dependent assumptions. In this
paper we extend one of the previous analyses, the case of a WIMP with a purely
spin-independent coupling, by discussing in detail the implications on the
results of the uncertainties on the dark matter galactic velocity distribution.
We study in a systematic way possible departures from the isothermal sphere
model, which is the parameterization usually adopted to describe the halo. We
specifically consider modifications arising from various matter density
profiles, effects due to anisotropies of the velocity dispersion tensor and
rotation of the galactic halo. The hypothesis of WIMP annual modulation,
already favoured in the previous analysis using an isothermal sphere, is
confirmed in all the investigated scenarios, and the effects of the different
halo models on the determination of the allowed maximum-likelihood region in
the WIMP mass and WIMP-nucleon cross-section are derived and discussed.


title:
Hadronic light-by-light scattering contribution to the muon g-2 in
  large-N_C QCD

abstract:
  We present our recent semi-analytical evaluation of the pion-pole
contribution to hadronic light-by-light scattering, using a description of the
pion-photon-photon form factor based on large-N_C and short-distance properties
of QCD. Inclusion of all light pseudoscalar states leads to a_{mu}(LbyL;PS) = +
8.3 (1.2) x 10^{-10}. We also sketch an effective field theory approach to
hadronic light-by-light scattering. It yields the leading logarithmic terms
that are enhanced by a factor N_C and shows that the sign of a_{mu}(LbyL;had)
cannot be inferred from a constituent quark-loop. In view of several
problematic issues that still remain to be clarified, our estimate for the full
hadronic light-by-light scattering contribution is a_{mu}(LbyL;had) = + 8 (4) x
10^{-10}.


title: A Mini-Review of Constraints on Extra Dimensions

abstract:
  We present a mini-review of present constraints of the large extra dimension
scenario. We show many experiments and considerations that can constrain the
fundamental scale of the large extra dimension. We observe that constraints
come from collider experiments are much weaker than those of astrophysical and
cosmological considerations. When the number of extra dimension n is smaller
than 4, the constraint is so strong that the large extra dimension scenario
cannot solve hierarchy problem. But when n >= 4 there is still possibility that
it can solve the hierarchy problem.


title: Mystery of Vacuum Energy or Rise and Fall of Cosmological Constant

abstract:
  Two sides of cosmological constant problem are discussed: a mysterious
compensation of all contributions to vacuum energy with the accuracy of 100-50
orders of magnitude and a surprising equality of a constant vacuum energy
density to the present-day value of time dependent cosmological energy density.


title:
Heavy Baryons: A Combined Large N_c and Heavy Quark Expansion for
  Electroweak Currents

abstract:
  The combined large N_c and heavy quark limit for baryons containing a single
heavy quark is discussed. The combined large N_c and heavy quark expansion of
the heavy quark bilinear operators is obtained. In the combined expansion the
corrections proportional to m_N/m_Q are summed to all orders. In particular,
the combined expansion can be used to determine semileptonic form factors of
heavy baryons in the combined limit.


title: The Three-Neutrino Mixing and Oscillations

abstract:
  The basics of neutrino oscillations is presented. Existing evidences of
neutrino oscillations, obtained in the atmospheric and solar neutrino
experiments, are considered. The new CHOOZ bound on the element $|U_{e3}|^{2}$,
obtained from the three-neutrino analysis of the data, is discussed. Decoupling
of neutrino oscillations in the solar neutrino range of $\Delta m^{2}$ is
considered.


title: Magnetic moments of the Lambda(1405) and Lambda(1670) resonances

abstract:
  By using techniques of unitarized chiral perturbation theory, where the
$\Lambda(1405)$ and $\Lambda(1670)$ resonances are dynamically generated, we
evaluate the magnetic moments of these resonances and their transition magnetic
moment. The results obtained here differ appreciably from those obtained with
existing quark models. The width for the $\Lambda(1670) \to \Lambda(1405)
\gamma$ transition is also evaluated leading to a branching ratio of the order
of $2 \times 10^{-6}$.


title:
Hierarchical radiative fermion masses and flavor changing processes in
  an $U(1)_X$ horizontal symmetry model

abstract:
  In a model with a gauge group $G_{SM}\otimes U(1)_X$, where $G_{SM} \equiv
SU(3)_C \otimes SU(2)_L \otimes U(1)_Y$ is the standard model gauge group and
$U(1)_X$ is a horizontal local gauge symmetry, the spectrum of charged fermion
masses and mixing angles are obtained from radiative contributions with the aim
to reproduce the fermion masses and the Cabibbo-Kobayashi-Maskawa matrix with
no {\it a priori} texture assumption. The assignment of horizontal charges is
made such that at tree level only the third family becomes massive when
electroweak symmetry is broken. Using these tree level masses and introducing
exotic scalars, the light families of charged fermions acquire hierarchical
masses through radiative corrections. The rank three mass matrices obtained are
written in terms of a minimal set of free parameters in order to estimate their
values by a numerical fit performance.
  The resulting masses and CKM mixing angles turn out to be in good agreement
with the known values.
  The new exotic scalar fields mediate flavor changing processes and contribute
to the anomalous magnetic moments of fermions, additionaly branching ratios an$
magnetic moments contributions were evaluated for leptons.


title:
Evolution of Baryon Rich Quark-Gluon Plasma and radiation of Single
  Photons

abstract:
  The (3+1) dimensional expansion of the quark gluon plasma (QGP) produced at
finite baryon density has been studied using relativistic hydrodynamical
approach. The pressure functional of the equation of state (EoS) has been
determined for the interacting nuclear matter with mesons exchange. The EoS has
been used to solve hydrodynamical equations using RHLLE algorithm. The space
time expansion of the plasma has been studied for the cases of SPS energy and
RHIC energy both at finite baryon density and for a hypothetical case of SPS
energy at zero baryon density. The space-time evolution is slowed and the life
times of QGP and mixed phases are shortened in the presence of finite baryon
density. The space time integrated total photon yields have been estimated by
convoluting the static emission rates with the space time expansion of the
plasma. It has been shown that the total photon yield at zero rapidity is not
significantly affected by the baryon density for SPS energy. The total photon
yield is unaffected by the Landau-Pomeranchuk-Migdal effect at SPS energy at
zero baryon density, as the quark matter contribution to photon yield is less
compared to hadronic matter.


title: Muon anomalous magnetic moment from effective supersymmetry

abstract:
  We present a detailed analysis on the possible maximal value of the muon
(g-2) (= 2 a_mu) within the context of effective SUSY models with R parity
conservation. First of all, the mixing among the second and the third family
sleptons can contribute at one loop level to the a_mu(SUSY) and tau -> mu gamma
simultaneously. One finds that the a_mu(SUSY) can be as large as (10-20)*10^-10
for any tan beta, imposing the upper limit on the tau -> mu gamma branching
ratio. Furthermore, the two-loop Barr-Zee type contributions to a_mu(SUSY) can
be significant for large tan beta, if a stop is light and mu and A_t are large
enough (O(1) TeV). In this case, it is possible to have a_mu(SUSY) upto
O(10)*10^-10 without conflicting with tau -> l gamma. We conclude that the
possible maximal value for a_mu(SUSY) is about 20*10^-10 for any tan beta.
Therefore the BNL experiment on the muon a_mu can exclude the effective SUSY
models only if the measured deviation is larger than \sim 30*10^-10.


title: The Cosmological Constant

abstract:
  Various contributions to the cosmological constant are discussed and
confronted with its recent measurement. We briefly review different scenarious
-- and their difficulties -- for a solution of the cosmological constant
problem.


title: Charmed and Bottom Baryons from Lattice NRQCD

abstract:
  The mass spectrum of charmed and bottom baryons has been computed on
anisotropic lattices using quenched lattice nonrelativistic QCD. Masses are
extracted by using mass splittings which are more accurate than masses obtained
directly by using the nonrelativistic mass-energy relation. Of particular
interest are the mass splittings between spin-1/2 and spin-3/2 heavy baryons,
and we find that these color hyperfine effects are not suppressed in the baryon
sector although they are known to be suppressed in the meson sector. Results
are compared with those obtained in a previous NRQCD calculation and with those
obtained from a Dirac-Wilson action of the D234 type.


title: Logarithmic Fingerprints of Virtual Supersymmetry

abstract:
  We consider the high energy behaviour of the amplitudes for production of
leptons, quarks, Higgs bosons, sleptons, squarks, gauge bosons, charginos,
neutralinos. We concentrate our discussion on the universal (process
independent) logarithmic terms which factorize the Born amplitude and which are
typically of the form [a ln(s/m^2)-ln^2(s/m^2)]. We perform a systematic
determination of the coefficient "a" for the various final states and we
emphasize the striking features which differentiate the SM and the MSSM cases.
We show that a comparison with experiments at future colliders should provide a
clean way to test the gauge and Higgs structures of the electroweak
interactions owing to the presence of sizeable (visible) virtual logarithmic
supersymmetric contributions.


title: Coupled channel study of a0 resonances

abstract:
  The coupled channel model of the a0(980) and a0(1450) resonances has been
constructed using the separable pion-eta and K-anti K interactions. We have
shown that two S-matrix poles corresponding to the a0(980) meson have
significantly different widths in the complex energy plane. The K-anti K to
pion-eta branching ratio, predicted in our model near the a0(1450) mass, is in
agreement with the result of the Crystal Barrel Collaboration. The K-anti K
interaction in the S-wave isovector state is not sufficiently attractive to
create a bound a0(980) meson.


title:
Numerical evaluation of the general massive 2-loop sunrise self-mass
  master integrals from differential equations

abstract:
  The system of 4 differential equations in the external invariant satisfied by
the 4 master integrals of the general massive 2-loop sunrise self-mass diagram
is solved by the Runge-Kutta method in the complex plane. The method, whose
features are discussed in details, offers a reliable and robust approach to the
direct and precise numerical evaluation of Feynman graph integrals.


title:
Consequences of the extra SM families on the Higgs boson production at
  Tevatron and LHC

abstract:
  The latest electroweak precission data allow the existence of additional
chiral generations in the standard model. We study the influence of extra
generations on the production of SM Higgs boson at hadron colliders. Due to the
enhancement of the gluon fusion channel, the ``golden mode'' becomes more
promising even at upgraded Tevatron. Furthermore, the formation of the fourth
family quarkonia with the subsequent $\eta_{4}\to ZH$ decay introduces
additional tool for the investigation of the Higgs boson properties.


title: A Modification of the Saturation Model: DGLAP evolution

abstract:
  We propose to modify the saturation model of Golec-Biernat and Wusthoff by
including DGLAP evolution. We find considerable improvement for the total deep
inelastic cross section, in particular in the large Q^2 region. The successful
description of DIS diffraction is preserved.


title:
Implementing initial state radiation for lepton induced processes in
  AMEGIC++

abstract:
  We have implemented the method of Yennie, Frautschi, and Suura up to first
order in alpha for the simulation of QED Initial State Radiation in lepton
induced processes in AMEGIC++. We consider s-channel processes via the exchange
of scalar or vector resonances at electron and muon colliders.


title: Self-similar Properties of the Proton Structure at low x

abstract:
  Self-similar properties of proton structure in the kinematic region of low
Bjorken x are introduced and studied numerically. A description of the proton
structure function F2(x,Q2) reflecting self-similarity is proposed with a few
parameters which are fitted to recent HERA data. The specific parameterisation
provides an excellent description of the data which cover a region of four
momentum transfer squared, 0.045 < Q2 < 120 GeV2, and of Bjorken x, 6.2E-7 < x
< 0.01.


title: CPT Violation and the Nature of Neutrinos

abstract:
  In order to accommodate the neutrino oscillation signals from the solar,
atmospheric, and LSND data, a sterile fourth neutrino is generally invoked,
though the fits to the data are becoming more and more constrained. However, it
has recently been shown that the data can be explained with only three
neutrinos, if one invokes CPT violation to allow different masses and mixing
angles for neutrinos and antineutrinos. We explore the nature of neutrinos in
such CPT-violating scenarios. Majorana neutrino masses are allowed, but in
general, there are no longer Majorana neutrinos in the conventional sense.
However, CPT-violating models still have interesting consequences for
neutrinoless double beta decay. Compared to the usual case, while the larger
mass scale (from LSND) may appear, a greater degree of suppression can also
occur.


title:
Scalar neutrino production in R-parity violating supersymmetric model at
  HERA

abstract:
  We investigate a single scalar neutrino production at the upgraded HERA with
high luminosity in the framework of an R-parityviolating supersymmetric model.
We find that the scalar neutrino with mass around 100GeV could be observed
through investigating the multilepton production process e- p -> mu-
sneutrino(tau) X -> mu- (e- mu+) X. The signal would be characterized by mu+
and e- with high transverse momentum as well as a sharp peak in the invariant
mass M(e-,mu+) distribution.


title: On the existence of Kalb-Ramond wormholes

abstract:
  Static spherically symmetric Kalb-Ramond (KR) traversable wormholes in
torsioned spacetime are shown not to exist globally since torsion vanishes not
only at the wormhole throat but in all spacetime points which means that all
components of the KR field vanish identically. With this result Hochberg-Visser
result on the non-violation of the weak energy (WEC) condition in the presence
of four-dimensional Einstein-Cartan-Kalb-Ramond (ECKR) geometry with totally
skew-symmetric Cartan torsion seems to be a trivial one.


title: One Loop Chiral Corrections to Hard Exclusive Processes:I. Pion Case

abstract:
  We computed the leading non-analytic chiral corrections to the generalized
parton distributions (GPDs) of the pion and to the two-pion distribution
amplitudes. This allows us to obtain the corresponding corrections for the hard
exclusive processes, such as gamma^* gamma -> pi pi, gamma^* N -> 2pi N' and
deeply virtual Compton scattering on the pion target.


title: On non hadronic origin of high energy neutrinos

abstract:
  Some of the non hadronic interactions, such as the \eta resonance formation
in the \gamma \gamma interactions and the muon pair production in the e\gamma
interactions, are identified as possible source interactions for generating
high energy neutrinos in the cosmos.


title: Probing Quintessence with Time Variation of Couplings

abstract:
  Many models of quintessence predict a time variation of the fundamental
constants as well as a composition-dependent gravity like long-range force
mediated by the cosmon. We present bounds for the cosmon coupling to matter and
radiation within a grand unified framework. The unification scale, the unified
gauge coupling and the Fermi scale are allowed to vary independently. We find
that the variation of the weak scale compared to the nucleon mass is severely
restricted. The violation of the equivalence principle turns out to be
substantially larger than in models where only the electromagnetic fine
structure constant varies with time. We also show that in contrast to gravity
the local cosmon field in a condensed object does not decouple from the
cosmological evolution. In consequence, the cosmon interaction constitutes a
possible quantitative link between cosmological observations and several areas
of high precision experiments concerning the local time or space variation of
couplings and tests of the equivalence principle.


title: Diffractive Higgs boson production at the Tevatron and LHC

abstract:
  Improved possibilities to find the Higgs boson in diffractive events, having
less hadronic activity, depend on whether the cross section is large enough.
Based on the soft color interaction models that successfully describe
diffractive hard scattering at HERA and the Tevatron, we find that only a few
diffractive Higgs events may be produced at the Tevatron, but we predict a
substantial rate at the LHC.


title: Positivity bounds on parton distributions at large N_c

abstract:
  Positivity bounds for twist-two parton distributions in multicolored QCD are
stronger than their analogs at finite $N_c$. They include the enhanced large
$N_{c}$ version of Soffer inequality. These bounds are compatible with the
DGLAP evolution to higher normalization points.


title: Photoproduction of W Bosons at HERA: QCD Corrections

abstract:
  W bosons can be produced in the channels e+- p -> W+- + X at HERA thus
allowing to probe for anomalous trilinear couplings among the gauge bosons. We
discuss the NLO QCD corrections to the photoproduction of W bosons with finite
transverse momentum at HERA. The higher-order QCD corrections reduce the
factorization scale dependence significantly and modify the leading order cross
sections by +-O(10%).


title:
Associated production of H^{\pm} and W^{\mp} in high-energy e+e-
  collisions in the Minimal Supersymmetric Standard Model

abstract:
  We study the associated production of the charged Higgs boson and W^{\pm}
gauge boson in high energy e+e- collisions in the Minimal Supersymmetric
Standard Model (MSSM). This associated production, which first arises at the
one loop level, offers the possibility of producing the charged Higgs boson at
the e+e- collider with mass more than half the center-of-mass energy, when the
charged Higgs pair production is kinematically forbidden. We present analytic
and numerical results for the cross section for e+e- --> W+ H- in the full
MSSM, taking into account the previously uncalculated contributions from
supersymmetric (SUSY) particles. We find that the contributions of the SUSY
particles enhance the cross section over most of SUSY parameter space,
especially when the SUSY particles are light, ~200 GeV. With favorable SUSY
parameters, at small tan beta, this process can yield more than ten
W^{\pm}H^{\mp} events for m_{H^{\pm}} <~ 350 GeV in 500 fb-1 at a 500 GeV e+e-
collider, or m_{H^{\pm}} <~ 600 GeV in 1000 fb-1 at a 1000 GeV collider. 80%
left-handed polarization of the e- beam improves these reaches to m_{H^{\pm}}
<~ 375 GeV and m_{H^{\pm}} <~ 670 GeV, respectively.


title: Notes on the Deconfining Phase Transition

abstract:
  I review the deconfining phase transition in an SU(N) gauge theory without
quarks. After computing the interface tension between Z(N) degenerate vacua
deep in the deconfined phase, I follow Giovannangeli and Korthals Altes, and
suggest a new model for (discrete) Polyakov loop spins. Effective theories for
(continuous) Polyakov loop spins are constructed, including those with Z(N)
charge greater than one, and compared with Lattice data. About the deconfining
transition, the expectation values of Z(N) singlet fields (``quarkless
baryons'') may change markedly. Speculations include: a possible duality
between Polyakov loop and ordinary spins in four dimensions, and how Z(N)
bubbles might be guaranteed to have positive pressure.


title: Flux of Atmospheric Neutrinos

abstract:
  Atmospheric neutrinos produced by cosmic-ray interactions in the atmosphere
are of interest for several reasons. As a beam for studies of neutrino
oscillations they cover a range of parameter space hitherto unexplored by
accelerator neutrino beams. The atmospheric neutrinos also constitute an
important background and calibration beam for neutrino astronomy and for the
search for proton decay and other rare processes. Here we review the literature
on calculations of atmospheric neutrinos over the full range of energy, but
with particular attention to the aspects important for neutrino oscillations.
Our goal is to assess how well the properties of atmospheric neutrinos are
known at present.


title: Physics potential and present status of neutrino factories

abstract:
  I briefly review the recent status of research on physics potential of
neutrino factories with emphasis on measurements of the CP phase.


title: Constraints on $\tan{\beta}$ in SUSY SU(5) GUT

abstract:
  On the evaluation of $\tan{\beta}$ is revisited by the method of the
renormalization group with the criteria of the bottom-tau unification in the
SUSY SU(5) GUT model. Among the conventional supersymmetric theories, an
energy-scale constant $M_{SUSY}$ is introduced by-hand to decouple the lower
energy-scale region from the effects of the supersymmetric particles. Provided
that $M_{SUSY}$ really exists, only small $\tan{\beta} \simeq 2$ is allowed
theoretically. While, medium value as $\tan{\beta} = 6 \sim 25$ is also
supported if $M_{SUSY}$ is vanished away from the model.


title:
Adiabatic perturbations in pre big bang models: matching conditions and
  scale invariance

abstract:
  At low energy, the four-dimensional effective action of the ekpyrotic model
of the universe is equivalent to a slightly modified version of the pre big
bang model. We discuss cosmological perturbations in these models. In
particular we address the issue of matching the perturbations from a collapsing
to an expanding phase in full generality. We show that, generically, one
obtains $n=0$ for the spectrum of scalar perturbations in the original pre big
model (with vanishing potential). When an exponential potential for the dilaton
is included, a scale invariant spectrum ($n=1$) of adiabatic scalar
perturbations is produced under very generic matching conditions, both in a
modified pre big bang and ekpyrotic scenario. We also derive general results
valid for power law scale factors matched to a radiation dominated era.


title: Chiral structure of nucleon gravitational form factors

abstract:
  We study the low momentum behavior of nucleon gravitational form factors in
the framework of the heavy baryon chiral perturbation theory. At zero recoil
they determine the momentum and spin apportion between nucleon constituents.
Our result provides an insight into the response of the nucleon's pion cloud to
an external weak gravitational field and establishes a theoretical framework
for extrapolation of experimental and lattice data on the nucleon form factors
to zero momentum transfer. We also discuss form factors corresponding to
higher-rank tensor currents related to the moments of generalized parton
distributions.


title: Absence of two-flavor color-superconductivity in compact stars

abstract:
  The simplest pattern of color superconductivity involves BCS pairing between
up and down quarks. We argue that this ``2SC'' phase will not arise within a
compact star. A macroscopic volume of quark matter must be electrically neutral
and must be a color singlet. Satisfying these requirements imposes a
significant free energy cost on the 2SC phase, but not on color-flavor locked
(CFL) quark matter, in which up, down and strange quarks all pair. As a
function of increasing density, therefore, one may see a single phase
transition from hadronic matter directly to CFL quark matter. Alternatively,
there may be an intervening phase in which the different flavors self-pair, or
pair with each other in a non-BCS pattern, such as in a crystalline color
superconductor.


title:
Top quark Kaluza-Klein mode mixing in the Randall-Sundrum bulk Standard
  Model and B -> X_s gamma

abstract:
  We study top quark Kaluza-Klein (KK) mode mixing in the Randall-Sundrum
scenario with all the SM fermions and gauge bosons in the bulk. Even though the
simple assumption of universal bulk fermion mass m_psi leads to the same KK
mass spectrum for all the SM fermions and thus suppresses new contributions to
the flavor changing neutral current and the rho parameter, large Yukawa
coupling of the top quark generates the mixing among its KK modes and breaks
the degeneracy: Unacceptably large contribution to rho occurs. In order to
satisfy the rho constraint, we relax the model by assigning a different bulk
fermion mass to SU(2) singlet bottom quark, and demonstrate that there exists
some limited parameter space where the $\Delta\rho$ constraint is satisfied. It
is also shown that the current measurement of Br(B -> X_s + gamma) can be
accommodated in this modified model, and one sigma level precision constrains
the effective weak scale k_{EW} such as k_{EW} ~ 3 TeV for m_psi/k=-0.4, where
k_{EW} is the warp-suppressed AdS_5 curvature.


title: On the Phase Space Partition in High Energy Collisions

abstract:
  In high energy hadron-hadron and e+e- collisions, to isolate a part of the
phase space in multi-hadron final states is necessary for exploring the
underlying dynamics. It is shown that the partition of phase space according to
the value of rapidity, popularly used in hadron-hadron collisions, is
inappropriate for the study of e+e- collisions. The proper way in the latter
case is to identify the visible jets and take them as objects for detailed
study, forming an extended phase space. The value y_cut^(0) of the
distance-measure for the identification of visible jets is determined. A new
variable $r$ is introduced to further partition the phase space inside jets,
which possesses a very good anomalous scaling property, showing that the
$r$-distribution inside jets is a self-similar fractal.


title:
Leading-twist Single-transverse-spin asymmetries: Drell-Yan and
  Deep-Inelastic Scattering

abstract:
  Recently, Brodsky, Hwang and Schmidt have proposed a new mechanism that gives
a transverse spin symmetry at leading twist in semi-inclusive deep-inelastic
scattering. I show that the new mechanism is compatible with factorization and
is due to an transverse-spin asymmetry in the k_T distribution of quarks in a
hadron (the "Sivers asymmetry"). An earlier proof that the Sivers asymmetry
vanishes because of time-reversal invariance is invalidated by the path-ordered
exponential of the gluon field in the operator definition of parton densities.
Instead, the time-reversal argument shows that the Sivers asymmetry is reversed
in sign in hadron-induced hard processes (e.g., Drell-Yan), thereby violating
naive universality of parton densities. Previous phenomenology with
time-reversal-odd parton densities is therefore validated.


title:
On the Large-$N_c$ Limit and Electroweak Interactions: Some Properties
  of the $N_c$-Extended Standard Model

abstract:
  We discuss properties of QCD with variable and large $N_c$, taking into
account electroweak interactions; i.e., we analyze the generalization of the
standard model based on the gauge group $G={\rm SU}(N_c) \times {\rm SU(2)}_L
\times {\rm U(1)}_Y$. General classes of solutions to anomaly constraints are
given, and it is shown that these allow a $T_3 = \pm 1/2$ quark or $T_3=-1/2$
lepton rather than the neutrino as an electrically neutral fermion. The issue
of grand unification is addressed, and it is shown that $G$ cannot be embedded
in the usual way in a simple SO($N$) or SU($N$) gauge group unless $N_c=3$. The
ratio of strengths of QCD and electroweak interactions is discussed.


title: Chiral symmetry restoration and the string picture of hadrons

abstract:
  QCD string picture of highly excited hadrons very naturally explains parity
doubling once the chiral symmetry is restored high in the spectrum. In
particular, the spin-orbit and tensor interactions of quarks at the ends of the
string, related to dynamics of the string, vanish. High in the spectrum there
appears higher degree of degeneracy, namely parity doublets with different
angular momentum cluster around energy of the string in the given quantum
state.


title:
Mesons of the $f_0$ family in processes $\pi\pi\to\pi\pi,K\bar{K}$ up to
  2 GeV and chiral symmetry

abstract:
  In a combined analysis of the experimental data on the coupled processes
$\pi\pi\to\pi\pi,K\bar{K}$ in the channel with $I^GJ^{PC}=0^+0^{++}$, the
various scenarios of these reactions (with different numbers of resonances) are
considered. In a model-independent approach, based only on analyticity and
unitarity, a resonance is represented by of a pole cluster (poles on the
Riemann surface) of the definite type that is defined by the state nature. The
best scenario contains the resonances $f_0(665)$ (with properties of the
$\sigma$-meson), ${f_0}(980)$ (with a dominant $s{\bar s}$ component),
$f_0(1500)$ (with a dominant flavour-singlet, {\it e.g.}, glueball component)
and the ${f_0}(1710)$ (with a considerable $s{\bar s}$ component). If the
${f_0}(1370)$ exists, it has a dominant $s{\bar s}$ component. The coupling
constants of observed states with the considered channels and the $\pi\pi$ and
$K\bar{K}$ scattering lengths are obtained. The conclusion on the linear
realization of chiral symmetry is drawn.


title:
Physics potential of future long baseline neutrino oscillation
  experiments with KEK-JAERI HIPA

abstract:
  We study physics potential of Very Long Base-Line (VLBL) Neutrino-Oscillation
Experiments with the High Intensity Proton Accelerator, which will be completed
by the year 2007 in Tokai-village, Japan. As a target, a 100 kton-level
water-$\check {\rm C}$erenkov detector is considered at 2,100 km away. Assuming
the pulsed narrow-band $\nu_\mu$ beams, we study sensitivity of such
experiments to the neutrino mass hierarchy, the mass-squared differences, one
CP phase and three angles of the lepton-flavor-mixing matrix. We find that
experiments at a distance 2,100 km can determine the neutrino mass hierarchy if
the mixing matrix element $|U_{e3}|$ is not too small. The CP phase and
$|U_{e3}|$ can be constrained if the large-mixing-angle solution of the
solar-neutrino deficit is realized.


title:
A Deduced Feynman Rule for Calculating Retarded and Advanced Green
  function in Closed Time Path Formalism

abstract:
  Based on the closed time path formalism, a new Feynman rule for directly
calculating the retarded and advanced Green functions is deduced. This Feynman
rule is used to calculate the two-point self-energy and three-point vertex
correction in $\phi^3$ theory. The generalized fluctuation-dissipation theorem
for three-point nonlinear response function is verified.


title: Charged Particle Fluctuation in Heavy Ion Collisions

abstract:
  Comparing quantities to analyze charged fluctuations in heavy ion experiments
the dispersion of the charges in a central rapidity box was found to be best
suited. Various energies and different nuclear sizes are considered in an
explicit Dual-Parton-Model calculation using the DPMJET code and a randomized
modification to simulated charge equilibrium. For large enough detection
regions charged particle fluctuations can provide a signal of the basic
dynamics of heavy ion processes.


title:
Negative strange quark-chemical potential. A necessary and sufficient
  observable of the deconfinement phase transition in a finite baryon
  equilibrated state

abstract:
  We consider the variation of the strange quark-chemical potential in the
phase diagramme of nuclear matter, employing the order parameters and
mass-scaled partition functions in each domain and enforcing flavour
conservation. Assuming the region beyond the hadronic phase to be described by
massive, correlated and interacting quarks, in the spirit of NJL and lattice
calculations, we find the strange quark-chemical potential to attain large
negative values in this domain. We propose that this change in the sign of the
strange quark-chemical potential from positive in the hadronic phase to
negative in the partonic, to be a unique, concise and well-defined indication
of the quark deconfinement phase transition in nuclear matter. We propose also
that, for a chemically equilibrated state in the deconfined region, which
follows an isentropic expansion to hadronization via a second order phase
transition, the fugacities of the equilibrated quark flavours, once fixed in
the primordial state, remain constant throughout the hadronization process.


title: Glueballs and AdS/CFT

abstract:
  I review the calculation of the glueball spectrum in non-supersymmetric
Yang-Mills theory (in 3 and 4 dimensions) using the conjectured duality between
supergravity and large N gauge theories. The glueball masses are obtained by
solving the supergravity wave equations in a black hole geometry. The masses
obtained this way are in unexpectedly good agreement with the available lattice
data, and are much better than strong-coupling expansion results. I also show
how to use a modified version of the duality to calculate the glueball mass
spectrum with some of the Kaluza-Klein states of the supergravity theory
decoupled from the spectrum.


title: Neutrino Mass from Triplet and Doublet Scalars at the TeV Scale

abstract:
  If the minimal standard model of particle interactions is extended to include
a scalar triplet with lepton number $L=-2$ and a scalar doublet with $L=-1$,
neutrino masses $m_\nu \sim \mu_{12}^4 v^2/M^5 \sim 10^{-2}$ eV is possible,
where $v \sim 10^2$ GeV is the electroweak symmetry breaking scale, $M \sim 1$
TeV is the typical mass of the new scalars, and $\mu_{12} \sim 1$ GeV is a soft
lepton-number-violating parameter.


title: Classical chromo-dynamics of relativistic heavy ion collisions

abstract:
  Relativistic heavy ion collisions produce thousands of particles, and it is
sometimes difficult to believe that these processes allow for a theoretical
description directly in terms of the underlying theory - QCD. However once the
parton densities are sufficiently large, an essential simplification occurs -
the dynamics becomes semi-classical. As a result, a simple ab initio approach
to the nucleus--nucleus collision dynamics may be justified. In these lectures,
we describe the application of these ideas to the description of
multi--particle production in relativistic heavy ion collisions. We also
discuss the role of semi-classical fields in the QCD vacuum in hadron
interactions at low and high energies.


title: An Approximate Light Cone Method to Investigate Meson Structure

abstract:
  To appear in the proceedings of The Phenomenology of Large N(c) QCD, Tempe,
Arizona, 9-11 Jan 2002.


title: Constraining Fourth Generation with $B\to X_s \gamma$

abstract:
  Using the theoretical and experimental results on $B \to X_s \gamma$, a
four-generation SM is analyzed to constrain the combination of the $4\times 4$
Cabibbo-Kobayashi-Maskawa factor $V_{t^\prime s}^* V_{t^\prime b}$ as a
function of the $t^\prime$--quark mass. It is observed that the results for the
above--mentioned physical quantities are essentially different from the
previous predictions for certain solutions of the CKM factor. Influences of the
new model is used to predict CP violation in $B \to X_s \gamma$ decay at the
order of $A_{CP}=5%$, stemming from the appearance of complex phases of
$V_{t^\prime s}^* V_{t^\prime b}$ and of Wilson coefficients $C_7$, $C_8$, in
the related process. The above mentioned physical quantities can serve as
efficient tools in search of the fourth generation.


title: CP Violation and Moduli Stabilization in Heterotic Models

abstract:
  The role of moduli stabilization in predictions for CP violation is examined
in the context of four-dimensional effective supergravity models obtained from
the weakly coupled heterotic string. We point out that while stabilization of
compactification moduli has been studied extensively, the determination of
background values for other scalars by dynamical means has not been subjected
to the same degree of scrutiny. These other complex scalars are important
potential sources of CP violation and we show in a simple model how their
background values (including complex phases) may be determined from the
minimization of the supergravity scalar potential, subject to the constraint of
vanishing cosmological constant.


title: QCD coherence effects in low-x DIS and Drell-Yan with nuclear targets

abstract:
  We investigate QCD coherence effects in deep inelastic scattering (DIS) off
nuclei and in Drell-Yan (DY) dilepton production in proton-nucleus collisions
within the light-cone color-dipole approach. The physical mechanisms underlying
the nuclear effects become very transparent in this approach and are explained
in some detail. We present numerical calculations of nuclear shadowing in DIS
and DY and compare to data. Nuclear effects in the DY transverse momentum
distribution are calculated as well. The dipole approach is the only known way
to calculate the Cronin effect without introducing additional parameters for
nuclear targets.


title: Bounds on the W-Boson Electric Dipole Moment -Revisited

abstract:
  Keeping in view the suggestion of Barr and Marciano [7] that the cut of
procedure involves a good deal of uncertainity in the prediction of E.D.M. of W
- boson, we have re-examined the earlier calculation by Marciano and Queijeiro
[2] by replacing the Cut-off regularization process by BPHZ regularization[8].
This works in a clean and unambiguous manner without involving any
approximation. We also examine apparently inapplicable approximations like
using m(f) = m(f')in [2]. The bounds on lambda(w) and d(w) are significantly
changed in all cases as compared with those reported in [2]. The necessary
caution that is to be excercised while using approximations is explicitly
pointed out. PACS number (s): 13.40. Em


title:
Revisit to Low Mass Scalar Mesons via Unitarized Chiral Perturbation
  Theory

abstract:
  We study how the scalar mesons below 1 GeV are generated through the
Oller-Oset-Pelaez version of the multichannel inverse amplitude method applied
to the chiral perturbation theory. We find out that the f0(980) state is
certainly generated as a bound state resonance below the K-Kbar threshold,
while the a0(980) state, generated through the channel coupling between the
pi-eta and K-Kbar channels, appears as a cusp at the K-Kbar threshold. The
so-called sigma(500) and kappa(900) need not be interpreted as the conventional
resonances.


title:
Degenerate and Inverted Hierarchical Models of Majorana Neutrinos from
  See-saw Mechanism

abstract:
  In order to explain the recently reported result on the double beta decay
$(0\nu\beta\beta)$ experiment, together with the earlier established data on
LMA MSW solar and atmospheric neutrino oscillations, we generate the textures
of the nearly degenerate as well as the inverted hierarchical models of the
left-handed Majorana neutrino mass matrices within the framework of the see-saw
mechanism in a model independent way.
  The leptonic mixings are generated from the texture of the right- handed
Majorana mass matrices while keeping the Dirac neutrino mass matrices in
diagonal forms.


title:
String model description of polarisation and angular distributions in
  pbar p -> Lambdabar Lambda at low energies

abstract:
  The observed polarisation of Lambda hyperons from the inclusive pA -> Lambda
X reaction at high energies has previously been well described within the Lund
string model through polarised ss quark pair production in the string breaking
hadronisation process. This model is here applied to the exclusive pbar p ->
Lambdabar Lambda reaction at low energies and compared to available data sets
down to an incident beam momentum of 1.835 GeV/c. This required an extension of
the diquark scattering model to involve three components: an isotropic part
relevant close to threshold, a spectator part and a forward scattering part as
in pA -> Lambda X at high energies. The observed angular distributions are then
reproduced and, for momentum transfers above |t'| = 0.2 GeV^2, agreement with
the measured polarisation is also obtained.


title: Cross section of isolated prompt photons in hadron-hadron collisions

abstract:
  We consider the production of isolated prompt photons in hadronic collisions.
We present a general discussion in QCD perturbation theory of the isolation
criterion used by hadron collider experiments. The isolation criterion is
implemented in a computer programme of the Monte Carlo type, which evaluates
the production cross section at next-to-leading order accuracy in perturbative
QCD. The calculation includes both the direct and the fragmentation components
of the cross section, without any approximation of the dependence on the radius
R of the isolation cone. We examine the scale dependence of the isolated cross
section, the sensitivity of the cross section to the values of the isolation
parameters, and we provide a quantitative comparison between the full R
dependence and its small-R approximation.


title: Electroweak form factors of non-strange baryons

abstract:
  We compute electroweak form factors of the nucleon and photon transition form
factors of non-strange baryon resonances up to the third resonance region in a
model with instanton-induced interaction. The calculation is based on the
Bethe-Salpeter equation for three light constituent quarks and is fully
relativistic (U. L\"oring {\it et al.}, Eur. Phys. J. {\bf A10}, 309 (2001)).
Static nucleon properties and photon resonance couplings are in good agreement
with experiment and the $Q^2$-behaviour of the experimentally known form
factors up to large momentum transfer is accounted for.


title: Is There a Significant Excess in Bottom Hadroproduction at the Tevatron?

abstract:
  We discuss the excess in the hadroproduction of B mesons at the Tevatron. We
show that an accurate use of up-to-date information on the B fragmentation
function reduces the observed excess to an acceptable level. Possible
implications for experimental results reporting bottom quark cross sections,
also showing an excess with respect to next-to-leading order theoretical
predictions, are discussed.


title: Instantons and the Large N_c Limit of QCD

abstract:
  We summarize our current understanding of instantons in the large N_c limit
of QCD. We also present some recent results from simulations of the instanton
liquid in QCD for N_c>3.


title:
Baryogenesis via Lepton Number Violation and Family Replicated Gauge
  Group

abstract:
  We developed a previous model fitting all quark and lepton -- including
neutrino quantities in the region of the Large Mixing Angle-MSW solar solution
-- order of magnitudewise by only six adjustable parameters (Higgs vacuum
expectation values) to also give an agreeing prediction for the amount of
baryogenesis produced in the early time of cosmology. We use Fukugita-Yanagida
scheme and take into account now also the effect of the remormalisation
equation for the Dirac neutrino sector from Planck scale to the see-saw scale.
The present version of our model with many approximately conserved (gauge)
charges distinguishing various left- and right-Weyl particles has the largest
matrix element of the mass matrix for the three flavour see-saw neutrinos being
the off-diagonal elements associated with the second- and third-proto-flavour
and gives the ratio of baryon number density to the entropy density to
2.59{+17.0\atop-2.25}\times 10^{-11} which agrees perfectly well as do also all
the fermion masses and their mixing angles order of magnitudewise.


title: Forward Quark Jets from Protons Shattering the Colored Glass

abstract:
  We consider the single-inclusive minijet cross section in pA at forward
rapidity within the Color Glass Condensate model of high energy collisions. We
show that the nucleus appears black to the incident quarks except for very
large impact parameters. A markedly flatter p_t distribution as compared to QCD
in the dilute perturbative limit is predicted for transverse momenta about the
saturation scale, which could be as large as Q_s^2 ~ 10 GeV^2 for a gold
nucleus boosted to rapidity ~10 (as at the BNL-RHIC).


title:
Bayesian analysis of the constraints on gamma from B --> K pi rates and
  CP asymmetries in the flavour-SU(3) approach

abstract:
  The relation between the branching ratios and direct CP asymmetries of B -->
K pi decays and the angle gamma of the CKM unitarity triangle is studied
numerically in the general framework of the SU(3) approach, with minimal
assumptions about the parameters not fixed by flavour-symmetry arguments.
Experimental and theoretical uncertainties are subjected to a statistical
treatment according to the Bayesian method. In this context, the experimental
limits recently obtained by CLEO, BaBar and Belle for the direct CP asymmetries
are translated into the bound |gamma - 90 deg| > 21 deg at the 95% C.L.. A
detailed analysis is carried out to evaluate the conditions under which
measurements of the CP averaged branching ratios may place a significant
constraint on gamma. Predictions for the ratios of charged (R_c) and neutral
(R_n) B --> K pi decays are also presented.


title: Supersymmetric SU(3)^3 unification with Anomalous U(1)_A Gauge Symmetry

abstract:
  We consider supersymmetric unification based on the gauge symmetry
SU(3)_C\times SU(3)_L\times SU(3)_R supplemented by an anomalous U(1)_A gauge
symmetry. Realistic fermion masses and mixings are realized, including large
mixings in the neutrino sector. We also consider the supersymmetric flavor
problem, gauge coupling unification and proton decay. The dominant proton decay
mode is expected to be p-> e^+\pi^0 and the lifetime is estimated to be \sim
10^{34}-10^{35} years.


title: The Beyond the Standard Model Working Group: Summary Report

abstract:
  Report of the "Beyond the Standard Model" working group for the Workshop
`Physics at TeV Colliders', Les Houches, France, 21 May - 1 June 2001. It
consists of 18 separate parts:
  1. Preface;
  2. Theoretical Discussion;
  3. Numerical Calculation of the mSUGRA and Higgs Spectrum;
  4. Theoretical Uncertainties in Sparticle Mass Predictions;
  5. High Mass Supersymmetry with High Energy Hadron Colliders;
  6. SUSY with Heavy Scalars at LHC;
  7. Inclusive Study of MSSM in CMS;
  8. Establishing a No-Lose Theorem for NMSSM Higgs Boson Discovery at the LHC;
  9. Effects of Supersymmetric Phases on Higgs Production in Association with
Squark Pairs in the Minimal Supersymmetric Standard Model;
  10. Study of the Lepton Flavour Violating Decays of Charged Fermions in SUSY
GUTs;
  11. Interactions of the Goldstino Supermultiplet with Standard Model Fields;
  12. Attempts at Explaining the NuTeV Observation of Di-Muon Events;
  13. Kaluza-Klein States of the Standard Model Gauge Bosons: Constraints From
High Energy Experiments;
  14. Kaluza-Klein Excitations of Gauge Bosons in the ATLAS Detector;
  15. Search for the Randall Sundrum Radion Using the ATLAS Detector;
  16. Radion Mixing Effects on the Properties of the Standard Model Higgs
Boson;
  17. Probing Universal Extra Dimensions at Present and Future Colliders;
  18. Black Hole Production at Future Colliders.


title: Bulk Hadron Production at AGS and SPS

abstract:
  With new data available from the SPS, at 40 and 80 GeV/A, I review the
systematics of bulk hadron multiplicities, with prime focus on strangeness
production. The classical concept of strangeness enhancement in central AA
collisions is reviewed, in view of the statistical hadronization model which
suggests to understand strangeness enhancement to arise chiefly in the
transition from the canonical to the grand canonical version of that model. I.
e. enhancement results from the fading away of canonical suppression. The model
also captures the striking strangeness maximum observed in the vicinity of
$\sqrt{s} \approx $ 8 GeV. A puzzle remains in the understanding of apparent
grand canonical order at the lower SPS, and at AGS energies.


title:
Top quark associated production of the neutral top-pion at high energy
  $e^{+}e^{-}$ colliders

abstract:
  In the context of topcolor-assisted technicolor (TC2) models, we calculate
the associated production of the neutral top-pion $\pi_{t}^{0}$ with a pair of
top quarks via the process $e^{+}e^{-}\longrightarrow t\bar{t}\pi_{t}^{0}$. We
find that the production cross section is larger than that of the process $
e^{+}e^{-}\longrightarrow t\bar{t}H$ both in the standard model (SM) and in the
minimal supersymmetric SM. With reasonable values of the parameters in TC2
models, the cross section can reach $20fb$. The neutral top-pion $\pi_{t}^{0}$
may be direct observed via this process.


title:
Rapidity dependence of particle production in ultrarelativistic nuclear
  collisions

abstract:
  We compute the rapidity dependence of particle and transverse energy
production in ultrarelativistic heavy ion collisions at various beam energies
and atomic numbers using the perturbative QCD + saturation model. The
distribution is a broad gaussian near $y=0$ but the rapid increase of particle
production with the beam energy will via energy conservation strongly constrain
the rapidity distribution at large $y$.


title: Octet baryon magnetic moments in light cone QCD sum rules

abstract:
  Octet baryon magnetic moments are calculated in framework of the light cone
QCD sum rules. The analysis is carried for the general form of the
interpolating currents for octet baryons. A comparison of our results on the
magnetic moments of octet baryons with the predictions of other approaches and
experimental data is presented.


title: All-orders infra-red freezing of R(e+e-) in perturbative QCD

abstract:
  We consider the behaviour of the perturbative QCD corrections to the R(e+e-)
ratio in the limit that the c.m. energy sqrt(s) vanishes. We find that for
N(f)<9 flavours of massless quarks, the perturbative correction to the parton
model result freezes to the infra-red limit 2/b as s-->0. Here b=(33-2N(f))/6
is the first QCD beta-function coefficient. The freezing holds to all-orders in
perturbation theory. The s-dependence can be written analytically in closed
form in terms of the Lambert W function.


title: Proton Decay Signatures of Orbifold GUTs

abstract:
  In grand unified theories based on orbifold constructions in higher
dimensions, Higgsino-mediated proton decay is absent. However, proton decay
mediated by $X$ and $Y$ gauge bosons is typically enhanced to levels detectable
by current and future experiments. We analyse the phenomenology of proton decay
induced by the minimal coupling of $X,Y$ gauge bosons. In particular, we show
that the novel realization of matter in orbifold GUTs can lead to unusual final
state flavour structure, for example, the dominance of the $p\to K^0\mu^+$
mode. Furthermore, we discuss proton decay induced by higher-derivative brane
operators, finding potentially observable rates for natural values of the
operator coefficients.


title:
Signals of the Abelian Z' boson within the model independent analysis of
  the LEP data

abstract:
  The preliminary LEP data set on the total cross sections and the
forward-backward asymmetries of the $e^+e^-\to\bar{f}f$ processes are analysed
to establish a model-independent search for the signals of the virtual Abelian
Z' boson. The recently introduced observables giving possibility to pick up
uniquely the Z' signals in these processes are used. The mean values of the
observables are in accordance with the Z' detection at the $1\sigma$ accuracy.
The results of other model-independent fits and further prospects are
discussed.


title:
The analytical values of the sunrise master integrals for one of the
  masses equal to zero

abstract:
  The analytical values of the sunrise master amplitudes were found for one
mass equal to zero, two other arbitrary masses and an arbitrary external four
momentum. Differential equations in the square of the external four momentum
and masses were used to obtain the master integrals.


title: Effective Field Theoretical Approach to Black Hole Production

abstract:
  A field theoretical description of mini black hole production at TeV energies
is given taking into account the quantization of black holes in discrete
resonances. The unknown quantum gravitational effects are absorbed in effective
couplings, black hole masses and the Hawking temperature. The evaporation is
described in terms of thermal field theory.


title:
Non-universal Soft Parameters in Brane World and the Flavor Problem in
  Supergravity

abstract:
  We consider gravity mediated supersymmetry (SUSY) breaking in 5D spacetime
with two 4D branes B1 and B2 separated in the extra dimension. Using an
off-shell 5D supergravity (SUGRA) formalism, we argue that the SUSY breaking
scales could be non-universal even at the fundamental scale in a brane world
setting, since SUSY breaking effects could be effectively localized. As an
application, we suggest a model in which the two light chiral MSSM generations
reside on B1, while the third generation is located on B2, and the Higgs
multiplets as well as gravity and gauge multiplets reside in the bulk. For SUSY
breaking of the order of 10--20 TeV caused by a hidden sector localized at B1,
the scalars belonging to the first two generations can become sufficiently
heavy to overcome the SUSY flavor problem. SUSY breaking on B2 from a different
localized hidden sector gives rise to the third generation soft scalar masses
of the order of 1 TeV. Gaugino masses are also of the order of 1 TeV if the
size of the extra dimension is $\sim 10^{-16}$ ${\rm GeV}^{-1}$. As in 4D
effective supersymmetric theory, an adjustment of TeV scale parameters is
needed to realize the 100 GeV electroweak symmetry breaking scale.


title: Infrared Behaviour of The Gluon Propagator in Non-Equilibrium Situations

abstract:
  The infrared behaviour of the medium modified gluon propagator in
non-equilibrium situations is studied in the covariant gauge using the
Schwinger-Keldysh closed-time path formalism. It is shown that the magnetic
screening mass is non-zero at the one loop level whenever the initial gluon
distribution function is non isotropic with the assumption that the
distribution function of the gluon is not divergent at zero transverse
momentum. For isotropic gluon distribution functions, such as those describing
local equilibrium, the magnetic mass at one loop level is zero which is
consistent with finite temperature field theory results. Assuming that a
reasonable initial gluon distribution function can be obtained from a
perturbative QCD calculation of minijets, we determine these out of equilibrium
values for the initial magnetic and Debye screening masses at energy densities
appropriate to RHIC and LHC. We also compare the magnetic masses obtained here
with those obtained using finite temperature lattice QCD methods at similar
temperatures at RHIC and LHC.


title: Search of 1^P_1 charmonium in B decay

abstract:
  While experiment produced a candidate for the 1^P_1 chamonium in the past, it
still requires a confirmation. Given the recent progress in the exclusive B
decay into charmonia, we now have an opportunity to detect this charmonium
(h_c) by measuring the final state of the cascade decay B \to h_c K/K^* \to
\gamma \eta_c K/K^*. Confirmation of h_c may turn out to be much easier in the
B decay than at charm factories though one will have to work a little harder
for a high precision in mass determination.


title: Orbitally Excited Baryon Spectroscopy in the 1/Nc Expansion

abstract:
  The discussion of the 70-plet of negative parity baryons illustrates the
large Nc QCD approach to orbitally excited baryons. In the case of the l=1
baryons the existing data allows to make numerous predictions to first order in
the SU(3) symmetry breaking. New relations between splittings are found that
follow from the spin-flavor symmetry breaking. The Lambda(1405) is well
described as a three-quark state and a spin-orbit partner of the Lambda(1520).
Singlet states with higher orbital angular momentum are briefly discussed.


title: Bulk Majorons at Colliders

abstract:
  Lepton number violation may arise via the spontaneous breakdown of a global
symmetry. In extra dimensions, spontaneous lepton number violation in the bulk
implies the existence of a Goldstone boson, the majoron J^(0), as well as an
accompanying tower of Kaluza-Klein (KK) excitations, J^(n). Even if the
zero-mode majoron is very weakly interacting, so that detection in low-energy
processes is difficult, the sum over the tower of KK modes may partially
compensate in processes of relevance at high-energy colliders. Here we consider
the inclusive differential and total cross sections for e^- e^- --> W^- W^- J,
where J represents a sum over KK modes. We show that allowed parameter choices
exist for which this process may be accessible to a TeV-scale electron
collider.


title:
Multiple Parton Scattering in Nuclei: Twist-Four Nuclear Matrix Elements
  and Off-Forward Parton Distributions

abstract:
  Multiple parton scatterings inside a large nucleus generally involve
higher-twist nuclear parton matrix elements. The gluon bremsstrahlung induced
by multiple scattering depends not only on direct parton matrix elements but
also on momentum-crossed ones, due to the Landau-Pomeranchuk-Migdal
interference effect. We show that both types of twist-four nuclear parton
matrix elements can be factorized approximately into the product of twist-two
nucleon matrix elements in the limit of extremely large nuclei, $A\to \infty$,
as assumed in previous studies. Due to the correlative nature of the twist-four
matrix elements under consideration, it is actually the off-forward parton
distributions that appear naturally in this decomposition, rather than the
ordinary diagonal distributions probed in deeply-inelastic scattering. However,
we argue that the difference between these two distribution classes is small in
certain kinematic regimes. In these regions, the twist-four nuclear parton
matrix elements are evaluated numerically and compared to the factorized form
for different nuclear sizes within a schematic model of the two-nucleon
correlation function. The nuclear size dependence is found to be $A^{4/3}$ in
the limit of large $A$, as expected. We find that the factorization is
reasonably good when the momentum fraction carried by the gluon field is
moderate. The deviation can be more than a factor of 2, however, for small
gluon momentum fractions, where the gluon distribution is very large.


title: QCD evolution equations

abstract:
  We discuss QCD evolution equations for two and three particle correlation
functions of quarks and gluon fields in a hadron which describe development of
the momentum distribution of a parton system with a change of the wave length
of a probe which resolves it. We show in a general case of two-particle
correlators how the four-dimensional conformal algebra and the known pattern of
conformal symmetry breaking in QCD can be used to solve the complicated mixing
problem of local operators under renormalization and compute economically
anomalous dimensions of quark and gluon composite operators. An extension of
QCD to N = 1 super Yang-Mills theory and use of superconformal anomalies
arising after quantization allows to derive non-trivial relations between the
anomalous dimensions. For three-parton systems the conformal symmetry alone is
not enough to solve the three-particle problem. We show that in milticolor
limit of QCD there arises an extra conserved charge describing the solitonic
motion of the system of particles. The problem admits a one-to-one
correspondence with certain spin chain models which are exactly solvable.


title: Forward Compton Scattering, using Real Analytic Amplitudes

abstract:
  We analyze forward Compton scattering, using real analytic amplitudes. By
fitting the total \gamma p scattering cross section data in the high energy
region 5 GeV < \sqrt s < 20 GeV, using a cross section rising as \ln^2 s, we
calculate \rho_{\gamma p}, the ratio of the real to the imaginary portion of
the the forward Compton scattering amplitude, and compare this to \rho_{nn},
the ratio of the even portions of the pp and p-bar p forward scattering
amplitudes. We find that the two \rho-values are, within errors, the same in
the c.m.s. energy region 5 GeV < \sqrt s < 200 GeV, as predicted by a
factorization theorem of Block and Kadailov.


title: Nearly Tri-Bimaximal Neutrino Mixing and CP Violation

abstract:
  We point out two simple but instructive possibilities to modify the
tri-bimaximal neutrino mixing ansatz, such that leptonic CP violation can
naturally be incorporated into the resultant scenarios of nearly tri-bimaximal
flavor mixing. The consequences of two new ansaetze on solar, atmospheric and
reactor neutrino oscillations are analyzed. We also discuss an interesting
approach to construct lepton mass matrices under permutation symmetry, from
which one may derive another nearly tri-bimaximal neutrino mixing scenario with
no intrinsic CP violation in neutrino oscillations.


title: Can the Lepton Flavor Mixing Matrix Be Symmetric?

abstract:
  Current neutrino oscillation data indicate that the 3x3 lepton flavor mixing
matrix V is likely to be symmetric about its V_{e3}-V_{\mu 2}-V_{\tau 1} axis.
This off-diagonal symmetry corresponds to three pairs of {\it congruent}
unitarity triangles in the complex plane. Terrestrial matter effects can
substantially modify the genuine CP-violating parameter and off-diagonal
asymmetries of V in realistic long-baseline experiments of neutrino
oscillations.


title: The Problem of Large Leptonic Mixing

abstract:
  Unlike in the quark sector where simple $S_3$ permutation symmetries can
generate the general features of quark masses and mixings, we find it
impossible (under conditions of hierarchy for the charged leptons and without
considering the see-saw mechanism or a more elaborate extension of the SM) to
guarantee large leptonic mixing angles with any general symmetry or
transformation of only known particles. If such symmetries exist, they must be
realized in more extended scenarios.


title:
WPHACT 2.0: A fully massive Monte Carlo generator for four fermion
  physics at e^+ e^- colliders

abstract:
  WPHACT 2.0 is the new fully massive version of a MC program and unweighted
event generator which computes all Standard Model processes with four fermions
in the final state at e^+ e^- colliders. The program can now generate
unweighted events for any subset of all four fermion final states in a single
run, by making use of dedicated pre-samples which can cover the entire phase
space. Improvements with respect to WPHACT 1.0 include the Imaginary Fermion
Loop gauge restoring scheme, new phase space mappings, a new input system, the
possibility to compute subsets of Feynman diagrams and options for including
ISR via QEDPS, running alpha_{QED}, CKM mixing, resonances in q bar(q)
channels.


title:
Relativistic instant-form approach to the structure of two-body
  composite systems (short version)

abstract:
  A new approach to the electroweak properties of two--particle composite
systems is developed. The approach is based on the use of the instant form of
relativistic Hamiltonian dynamics. The main novel feature of this approach is
the new method of construction of the matrix element of the electroweak current
operator. The electroweak current matrix element satisfies the relativistic
covariance conditions and in the case of the electromagnetic current also the
conservation law automatically. The properties of the system as well as the
approximations are formulated in terms of form factors. The approach makes it
possible to formulate relativistic impulse approximation in such a way that the
Lorentz--covariance of the current is ensured. In the electromagnetic case the
current conservation law is also ensured. Our approach gives good results for
the pion electromagnetic form factor in the whole range of momentum transfers
available for experiments at present time, as well as for lepton decay constant
of pion.


title:
An Adiabatic Approximation to the Path Integral for Relativistic
  Fermionic Fields

abstract:
  A new approach to the path integral over fermionic fields, based on the
extension of a reformulation of the adiabatic approximation to some quantum
mechanical systems, is presented. A novel non-analytic contribution to the
efective fermionic action for a fermion field coupled to a non-Abelian vector
field is identified. The possible interpretation of this contribution as a
violation of the decoupling theorem in Quantum Field Theory (QFT) is discussed.
The generalization of the approach to the case of finite temperature and
density suggests the possibility to apply it to the understanding of
non-perturbative properties in QFT and their dependence on temperature and
density.


title: A hierarchical phase space generator for QCD antenna structures

abstract:
  We present a ``hierarchical'' strategy for phase space generation in order to
efficiently map the antenna momentum structures, typically occurring in QCD
amplitudes.


title:
Erratum to "Azimuthal asymmetry in electro-production of neutral pions
  in semi-inclusive DIS" published in Phys. Lett. B522 (2001) 37

abstract:
  We correct our analysis of the HERMES experiment for the azimuthal
sin(phi)-spin asymmetry in semi-inclusive hadroproduction in DIS on
longitudinally (with respect to the lepton momentum) polarized target because
of discovered misprint in sign in the paper P.J.Mulders and R.D.Tangerman,
Nucl. Phys. B 461 (1996) 197.


title: The dynamical models and the $Z \to b \bar{b}$ asymmetry}

abstract:
  Motivated by the $3.2\sigma(1.4\sigma)$ deviations between the recent
experimental value for $A_{FB}^{b}(R_{b})$ and the standard model(SM)
prediction, we examine the effect of new physics(NP) on the $Zb \bar{b}$
couplings $g_L^b$ and $g_R^b$. First we focus our attention on the dynamical
models. Then, using effective lagrangean techniques, we discuss the corrections
of NP to $g_L^b$ and $g_R^b$. We find some kinds of NP might explain the
recently experimental data about $R_b$ and $A_{FB}^b$. However, the free
parameters of these kinds of NP must be severely constrained.


title: Accessing Transversity in Double-Spin Asymmetries at the BNL-RHIC

abstract:
  We give upper bounds for transverse double-spin asymmetries in polarized
proton-proton collisions by saturating the positivity constraint for the
transversity densities at a low hadronic resolution scale. We consider prompt
photon, jet, pion, and heavy flavor production at the BNL Relativistic Heavy
Ion Collider (RHIC). Estimates of the expected statistical accuracy for such
measurements are presented, taking into account the acceptance of the RHIC
detectors.


title: New Perspective on Fermion Mass Matrices

abstract:
  It is shown that any $n \times n$ Dirac fermion mass matrix may be written as
the sum of $n$ states of equal ``mass''. However, these states are in general
not orthogonal. Thus the texture of any such fermion mass matrix may be
understood as the nonzero overlap among these states.


title: Polarized antiquark flavor asymmetry: Pauli blocking vs. the pion cloud

abstract:
  The flavor asymmetry of the unpolarized antiquark distributions in the
proton, dbar(x) - ubar(x) > 0, can qualitatively be explained either by Pauli
blocking by the valence quarks, or as an effect of the pion cloud of the
nucleon. In contrast, predictions for the polarized asymmetry Delta_ubar(x) -
Delta_dbar(x) based on rho meson contributions disagree even in sign with the
Pauli blocking picture. We show that in the meson cloud picture a large
positive Delta_ubar(x) - Delta_dbar(x) is obtained from pi-N - sigma-N
interference-type contributions, as suggested by chiral symmetry. This effect
restores the equivalence of the 'quark' and 'meson' descriptions also in the
polarized case.


title: Two RHIC puzzles: Early thermalization and the HBT problem

abstract:
  Hadron spectra from the first year RHIC run are shown to be excellently
reproduced by hydrodynamic calculations. We argue that in particular the
elliptic flow data provide strong evidence for early thermalization at RHIC, at
energy densities well above deconfinement, but that the phenomenologically
extracted short thermalization time scale of less than 1 fm/c provides a
serious challenge for theory. The HBT radii from the hydrodynamic calculations
agree only qualitatively with the data, showing significant quantitative
discrepancies. It is argued that this points to a still incomplete
understanding of the freeze-out process at RHIC.


title: R Symmetry and the Mu Problem

abstract:
  A natural origin for the mu and B parameters of weak scale supersymmetric
theories is proposed, applicable to any supersymmetry breaking messenger scale
between the weak and Planck scales. Although quite general, it requires
supersymmetric interactions to respect an R symmetry with definite quantum
numbers, and it requires some new scale of symmetry breaking. The required R
symmetry distinguishes the Higgs boson from the sneutrino, preserves baryon
number in operators of dimension four and five, and contains R parity so that
the lightest superpartner is stable. This origin for mu works for a variety of
mediation mechanisms, including gauge mediation, gaugino mediation, and
boundary condition breaking of supersymmetry. In any of these mediation
schemes, our mechanism leads to a real B parameter, and the supersymmetric CP
problem is solved. This R symmetry may naturally arise from supersymmetric
theories in higher dimensions.


title:
Supersymmetric Extra Dimensions: Gravitino Effects in Selectron Pair
  Production

abstract:
  We examine the phenomenological consequences of a supersymmetric bulk in the
scenario of large extra dimensions. We assume supersymmetry is realized in the
bulk and study the interactions of the resulting bulk gravitino Kaluza-Klein
(KK) tower of states, with supersymmetry breaking on the brane inducing a light
mass for the zero-mode gravitino. We derive the 4-d effective theory, including
the couplings of the bulk gravitino KK states to fermions and their scalar
superpartners. The virtual exchange of the gravitino KK states in selectron
pair production in polarized \epem collisions is then examined. We find that
the leading order operator for this exchange is dimension six, in contrast to
that of bulk graviton KK exchange which induces a dimension eight operator at
lowest order. The resulting kinematic distributions for selectron production
are dramatically altered from those in D=4 supersymmetric scenarios, and can
lead to a enormous sensitivity to the fundamental higher dimensional Planck
scale, of order $20-25\times \sqrt s$.


title: Superconducting K strings in high density QCD

abstract:
  Recently it has been argued that the ground state of high density QCD is
likely be a combination of the CFL-phase along with condensation of the K^0
field. This state spontaneously breaks a global U(1)_Y symmetry, therefore one
would expect the formation of U(1)_Y global strings. We discuss the core
structure of these strings and demonstrate that under some conditions the
global U(1)_Y symmetry may not be restored inside the string, in contrast with
the standard expectations. Instead, K^+ condensation occurs inside the core of
the string if a relevant parameter \cos\theta_K = \mkzero^2/\mu_eff^2 is larger
than some critical value \theta_K > \theta_crit. If this phenomenon happens,
the U(1)_Y strings become superconducting and may considerably influence the
magnetic properties of dense quark matter, in particular in neutron stars.


title: Polarization and Distribution Function of $\Lambda_b$ Baryon

abstract:
  The polarization of $\Lambda_b$ baryon has been measured in ALEPH, OPAL and
DELPHI experiments. A significant loss on the transfer of the $b$ quark
polarization to the $\Lambda_b$ baryon polarization has been noticed. This
implies that the hadronization effects can not be neglected. Therefore, we may
make use of the polarization measurements to look for suitable model for the
$\Lambda_b$ distribution function. To investigate nonperturbative effects
implied in the $\Lambda_b$ polarization, we construct four models based on a
perturbative QCD factorization formula. The models are the quark model (QM),
the modified quark model (MQM), the parton model (PM), and the modified parton
model (MPM). The modified models mean the models having transverse degrees of
freedom and the associated soft radiative corrections having been resummed. The
quark and parton models can not describe all experiments in the same time. On
the other hand, the modified models can have the power to explain all data in
the same formalism.


title:
Contributions of leptoquark interactions into the tensor and scalar form
  factors of K to pi l nu_l decay

abstract:
  In the framework of scalar-vector dominance we calculate the hadronic matrix
elements of scalar and tensor effective quark currents induced by virtual
leptoquark interactions. Combined bounds on the product of couplings and
leptoquark masses are obtained from experimental data.


title: Kaluza-Klein Effects on Higgs Physics in Universal Extra Dimensions

abstract:
  We examine the virtual effects of Kaluza-Klein (KK) states on Higgs physics
in universal extra dimension models. We study the partial widths $\Gamma_{h \to
gg}$, $\Gamma_{h \to \gamma \gamma}$, and $\Gamma_{h \to \gamma Z}$, which are
relevant for Higgs production and detection in future collider experiments.
These interactions occur at one loop in the Standard Model, as do the KK
contributions. We find that the deviations induced by the KK exchanges can be
significant; for one extra dimension, the $gg \to h$ production rate is
increased by $10% - 85%$ for the mass of the first KK state in the range $500
\gsim m_1 \gsim 1500$ GeV, a region untested by current direct search and
precision measurement constraints. The $h \to \gamma \gamma$ decay width is
decreased by $\lsim 20%$ in the same mass range. For two or more universal
extra dimensions the results are cutoff dependent, and can only be
qualitatively estimated. We comment on the detectability of these shifts at the
LHC and at future $e^+ e^-$ and $\gamma \gamma$ colliders.


title: QCD and Weak Interactions of Light Quarks

abstract:
  This review contains an overview of strong interaction effects in weak decays
starting with a historical introduction. It contains a short overview of
semileptonic decays and their relevance for measuring CKM matrix elements. The
main part is devoted to the theoretical calculation on nonleptonic matrix
elements relevant for $K^0$-$\bar{K^0}$ mixing and $K\to\pi\pi$ decays. It
concludes with a short summary of rare kaon decays.


title: (S)fermion Masses in Fat Brane Scenario

abstract:
  We discuss the fermion mass hierarchy and the flavor mixings in the fat brane
scenario of a five dimensional SUSY theory. Assuming that the matter fields
lives in the bulk, their zero mode wave functions are Gaussians, and Higgs
fields are localized on the brane, we find simple various types of the matter
configurations generating the mass matrices consistent with experimental data.
Sfermion mass spectrum is also discussed using the matter configurations found
above. Which type of squark mass spectra (the degeneracy, the decoupling and
the alignment) is realized depends on the relative locations of SUSY breaking
brane and the brane where Higgs fields are localized.


title: Soft lepton-flavor violation in a multi-Higgs-doublet seesaw model

abstract:
  We consider the Standard Model with an arbitrary number n_H of Higgs doublets
and enlarge the lepton sector by adding to each lepton family \ell a
right-handed neutrino singlet \nu_{\ell R}. We assume that all Yukawa-coupling
matrices are diagonal, but the Majorana mass matrix M_R of the right-handed
neutrino singlets is an arbitrary symmetric matrix, thereby introducing an
explicit but soft violation of all lepton numbers. We investigate
lepton-flavor-violating processes within this model. We pay particular
attention to the large-m_R behavior of the amplitudes for these processes,
where m_R is the order of magnitude of the matrix elements of M_R. While the
amplitudes for processes like tau^- --> mu^- gamma and Z --> tau^+ mu^- drop as
1/m_R^2 for arbitrary n_H, processes like tau^- --> mu^- e^+ e^- and mu^- -->
e^- e^+ e^- obey this power law only for n_H = 1. For n_H \geq 2, on the
contrary, those amplitudes do not fall off when m_R increases, rather they
converge towards constants. This non-decoupling of the right-handed scale
occurs because of the sub-process ell^- --> ell'^- {S_b^0}^*, where S_b^0 is a
neutral scalar which subsequently decays to e^+ e^-. That sub-process has a
contribution from charged-scalar exchange which, for n_H \geq 2, does not
decrease when m_R tends to infinity. We also perform a general study of the
non-decoupling and argue that, after performing the limit m_R --> \infty and
removing the \nu_R from the Lagrangian, our model becomes a multi-Higgs-doublet
Standard Model with suppressed flavor-changing Yukawa couplings. Finally, we
show that, with the usual assumptions about the mass scales in the seesaw
mechanism, the branching ratios of all lepton-flavor-changing processes are
several orders of magnitude smaller than present experimental limits.


title: Impact of CP phases on the search for sleptons tau and nu_tau

abstract:
  We study the decays of the tau-sleptons (stau_{1,2}) and tau-sneutrino
(snu_tau) in the Minimal Supersymmetric Standard Model (MSSM) with complex
parameters A_tau, mu and M_1 (U(1) gaugino mass). We show that the effect of
the CP phases of these parameters on the branching ratios of stau_{1,2} and
snu_tau decays can be quite strong in a large region of the MSSM parameter
space. This could have an important impact on the search for stau_{1,2} and
snu_tau and the determination of the MSSM parameters at future colliders.


title:
On Distinguishing Non-Standard Interactions from Radiative Corrections
  in Neutrino-Electron Scattering

abstract:
  We present a contribution of higher order to neutrino-electron scattering
that is a charged-current counterpart of both the anomalous axial-vector
triangle and possible non-standard interaction contributions. It arises in the
standard model with massive neutrinos, and renormalizes the nondiagonal
axial-vector form-factor at low energies. We show that, due to the small size
of radiative corrections, the neutrino-electron scattering still provides a
discovery potential for some of the non-standard neutrino interactions proposed
in the literature.


title: A minimal three generation seesaw scenario for LSND

abstract:
  We show that in the minimal three generation seesaw models for neutrinos, the
presence of leptonic $(L_e+L_{\mu}-L_{\tau})\times S_2$ symmetry leads to one
of the right handed neutrinos remaining massless. This state can then be
identified with the sterile neutrino required for a simultaneous understanding
of solar, atmospheric and LSND observations. We present a gauge model where the
presence of higher dimensional operators originating from Planck scale physics
lead to a realistic 2+2 mixed scenario that fits all oscillation data. The
model predicts a range for the mixing angle $U_{e3}$ and an effective mass for
neutrinos emitted in tritium decay, which can be used to test this model.


title:
Sufficiently Small $\bar{\theta}$ in $SU(3)^3 \times S_3$ Unification
  Model

abstract:
  Since CP violation in weak decays is successfully described by the KM
mechanism, the strong CP problem cannot easily be accommodated. This leads us
to reconsider the issue. If the axion and massless up quark are abandoned, we
must extend the standard model. Extension to $SU(3)^3 \times S_3$ unification
leads to the following situation: {\it if} CP is a high-energy symmetry and the
appropriate symmetry-breaking hierarchy of scales is in place, then the
$\bar{\theta}$ parameter of the QCD sub-theory is guaranteed to be sufficiently
small. We find $\bar{\theta} < 10^{-11}$ while the empirical limit from the
neutron electric dipole moment requires only that $\bar{\theta} < 1.3 \times
10^{-10}$.