title:
Inclusive dileptonic rare B decays with an extra generation of
  vector-like quarks

abstract:
  We investigate the leading effects of extending the Standard Model of
electroweak interactions by an extra iso-singlet up- and down- type quark pair
on various distributions and total branching ratio of the inclusive B-> X_s l^+
l^- (l =e,\mu) rare B decays. The presence of the extra vector-like down quark
$D$ results in the non-unitarity of the extended quark mixing matrix V, which
in turn leads to b-> s FCNC at the tree level proportional to (V^\dagger
V)_{sb}. On the other hand, the effective penguin and box vertex functions are
sensitive to the mass of the extra iso-singlet up quark m_U. The experimental
upper bound on BR(B-> X_s \mu^+ \mu^-) is used to constrain the parameters of
the model. It is shown that the shapes of the differential branching ratio and
forward-backward asymmetry distribution are very sensitive to the value of the
model parameters. We also calculate the CP aymmetry distribution of the
dileptonic decay in the vector-like quark model. It is shown that, for a
typical choice of the model parameters, asymmetries up to around 10% can be
achieved for certain values of the dilepton invariant mass.


title:
A Grand Canonical Ensemble Approach to the Thermodynamic Properties of
  the Nucleon in the Quark-Gluon Coupling Model

abstract:
  In this paper, we put forward a way to study the nucleon's thermodynamic
properties such as its temperature, entropy and so on, without inputting any
free parameters by human hand, even the nucleon's mass and radius. First we use
the Lagrangian density of the quark gluon coupling fields to deduce the Dirac
Equation of the quarks confined in the gluon fields. By boundary conditions we
solve the wave functions and energy eigenvalues of the quarks, and thus get
energy-momentum tensor, nucleon mass, and density of states. Then we utilize a
hybrid grand canonical ensemble, to generate the temperature and chemical
potentials of quarks, antiquarks of three flovars by the four conservation laws
of the energy and the valence quark numbers, after which, all other
thermodynamic properties are known. The only seemed free paremeter, the nucleon
radius is finally determined by the grand potential minimal principle.


title:
Thermodynamic Properties of Non-Equilibrium States in Quantum Field
  Theory

abstract:
  Within the framework of relativistic quantum field theory, a novel method is
established which allows to distinguish non-equilibrium states admitting
locally a thermodynamic interpretation. The basic idea is to compare these
states with global equilibrium states (KMS states) by means of local thermal
observables. With the help of such observables, the states can be ordered into
classes of increasing local thermal stability. Moreover, it is possible to
identify states exhibiting certain specific thermal properties of interest,
such as a definite local temperature or entropy density. The method is
illustrated in a simple model describing the spatio-temporal evolution of a
``big heat bang''.


title:
Indirect detection of neutralino dark matter candidates in
  anomaly-mediated supersymmetry breaking scenarios

abstract:
  We consider a model for neutralino dark matter candidates arising in
anomaly-mediated supersymmetry breaking schemes, and examine its testability
through the search for exotic cosmic rays produced by neutralino pair
annihilations in the dark halo of the Galaxy. We find that the model is already
constrained by available antiprotons and positrons measurements and may be
further tested in upcoming measurements of these cosmic ray species. We show
also that the monochromatic gamma-ray flux from neutralino annihilations is
enhanced in this model up to two orders of magnitude with respect to
alternative scenarios. The gamma-ray flux detected by the Energetic Gamma Ray
Experiment Telescope in the direction of the Galactic center exceeds
significantly the theoretical expectation of standard emission models. We prove
that if at least 10% of this excess is due to gamma-ray radiation with
continuum energy spectrum from neutralino annihilations in the model under
investigation, the associated gamma-ray line will be detected by upcoming
gamma-ray experiments.


title:
Prospects for supersymmetric charged Higgs boson discovery at the
  Tevatron and the LHC

abstract:
  We investigate the prospects for heavy charged Higgs boson production through
the mechanisms pp-bar(pp)->tbH+ +X at the upgraded Fermilab Tevatron and at the
upcoming LHC collider at CERN respectively. We focus on the MSSM case at high
values of tan[beta]> m_top/m_bot and include the leading SUSY quantum
corrections. A detailed study is performed for all important production modes
and basic background processes for the "ttbb" signature. At the upgraded
Tevatron a charged Higgs signal is potentially viable in the 220-250 GeV range
or excluded at 95%CL up to 300 GeV. At the LHC, a H+ of mass up to 800 GeV can
be discovered at 5 sigma or else be excluded up to a mass of ~ 1.5 TeV. The
presence ofSUSY quantum effects may highly influence the discovery potential in
both machines and can typically shift these limits by 200 GeV at the LHC.


title: Affleck-Dine leptogenesis with triplet Higgs

abstract:
  We study an extension of the supersymmetric standard model including a pair
of electroweak triplet Higgs $\Delta$ and ${\bar \Delta}$. The neutrinos
acquire Majorana masses mediated by these triplet Higgs fields rather than the
right-handed neutrinos. The successful leptogenesis for baryogenesis can be
realized after the inflation through the Affleck-Dine mechanism on a flat
manifold consisting of $\Delta$, ${\bar \Delta}$, ${\tilde e}^c$
(anti-slepton), even if the triplet Higgs mass $M_\Delta$ is much larger than
the gravitino mass $m_{3/2} \sim 10^3 {\rm GeV}$. Specifically, due to the
effects of the potential terms provided with the superpotential terms $M_\Delta
{\bar \Delta} \Delta$, $(\lambda_{L /} / 2M) {\bar \Delta} {\bar \Delta} e^c
e^c$, $(\lambda_\Delta / 2M) {\bar \Delta} \Delta {\bar \Delta} \Delta$
($\lambda_{L /} / \lambda_\Delta \sim 0.3 - 3$), the phases of $\Delta$, ${\bar
\Delta}$, ${\tilde e}^c$ are rotated at the time with the Hubble parameter $H
\sim M_\Delta$, producing generally the asymmetry with fraction $\epsilon_L
\sim 0.1$. If $M_\Delta$ is large enough, this early leptogenesis can be
completed before the thermal effects take place.


title:
LSND effect as a Chooz-restricted "sterile" perturbation of
  three-neutrino texture

abstract:
  Considering the hypothesis of mixing of three active neutrinos with, at
least, one sterile neutrino, we report on a simple $4\times 4$ texture whose $
3 \times 3 $ part arises from the popular bimaximal texture for three active
neutrinos $ \nu_e, \nu_\mu, \nu_\tau $, where $ c_{12} = 1/\sqrt{2} = s_{12}$,
$ c_{23} = 1/\sqrt{2} = s_{23}$ and $ s_{13} = 0$. Such a $3\times 3 $
bimaximal texture is perturbed through a rotation in the 14 plane, where $\nu_4
$ is the extra neutrino mass state induced by the sterile neutrino $\nu_s $
which becomes responsible for the LSND effect. Then, with $m^2_1\simeq m^2_2$
we predict that $\sin^2 2\theta_{\rm atm} = {1/2}(1+ c^2_{14}) \sim 0.99$ and
$\sin^2 2\theta_{\rm LSND} = {1/2}s^4_{14} \sim 4.5\times10^{-4}$, and in
addition $ \Delta m^2_{\rm atm} = \Delta m^2_{32}$ and $ \Delta m^2_{\rm LSND}
= |\Delta m^2_{41}|$, where $c^2_{14} = \sin^2 2\theta_{\rm sol} \sim 0.97$ and
$\Delta m^2_{21} = \Delta m^2_{\rm sol} \sim 10^{-7} {\rm eV}^2$ if {\it e.g.}
the LOW solar solution is applied. In this four-neutrino texture with $m^2_1
\simeq m^2_2 $ the sum rule $\sin^2 2 \theta_{\rm sol} + {1/2}\sin^2 2
\theta_{\rm Chooz} + \sin^2 2 \theta_{\rm LSND} = 1$ holds in the two-flavor
approximation (for each of three cases), leaving room for the LSND effect,
depending on the magnitude of Chooz effect that, not observed so far, leads (at
present) to the upper bound $\sin^2 2\theta_{\rm LSND}\stackrel{<}{\sim}
1.3\times10^{-3}$ and the lower bound $\sin^2 2\theta_{\rm sol}
\stackrel{>}{\sim} 0.95$. At the end a four-neutrino seesaw mechanism is
sketched.


title: Status of the Hadronic Contribution to the Muon (g-2) Value

abstract:
  With the recent interest in the measured and standard model values of the
muon anomalous magnetic moment, a_mu, some confusion has arisen concerning our
knowledge of the hadronic contribution to a_mu. In the dispersion integral
approach to hadronic vacuum polarization effects, low energy contributions must
be evaluated from data or in a model-dependent approach tested by data. At
higher energies perturbative QCD has been used, sometimes in conjunction with
data. The history of such evaluations is reviewed, and the prospects for
further improvement are discussed. We conclude that not all published
evaluations are on an equal footing or up-to-date. One must critically examine
which, and how much information went into each analysis in order to determine
which are more complete, and reliable.


title: Can R-parity violation lower $\sin 2\beta$?

abstract:
  Recent time-dependent CP asymmetry measurements in the $B_d \to J/\psi K_S$
channel by the BaBar and Belle Collaborations yield somewhat lower values of
$\sin 2\beta$ compared to the one obtained from the standard model fit. If the
inconsistency between these numbers persists with more statistics, this will
signal new physics contaminating the $B_d \to J/\psi K_S$ channel, thus
disturbing the extraction of $\beta$. We show that the R-parity-violating
interactions in supersymmetric theories can provide extra new phases which play
a role in significantly reducing the above CP asymmetry, thus explaining why
BaBar and Belle report lower values of $\sin 2\beta$. The same couplings also
affect the $B_d \to \phi K_S$ decay rate and asymmetry, explain the $B \to
\eta' K$ anomaly, and predict nonzero CP asymmetry in dominant $B_s$ decays.
The scenario will be tested in the ongoing and upcoming B factories.


title: The exclusive B_s -> phi mu+ mu- process in a constituent quark model

abstract:
  We consider the exclusive B_s -> phi mu+ mu- process in the standard model
using a constituent quark loop model approach together with a simple
parameterization of the quark dynamics. The model allows to compute the decay
form factors and therefore can give predictions for the decay rates, the
invariant mass spectra and the asymmetries. This process is suppressed in the
standard model but can be enhanced if new physics beyond the standard model is
present, such as flavor-violating supersymmetric models. It constitutes
therefore an interesting precision test of the standard model at forthcoming
experiments.


title: Dynamical Chiral Symmetry Breaking on a Brane in Reduced QED

abstract:
  Reduced gauge theories are theories in which while gauge fields propagate in
a bulk, fermion fields are localized on a brane. We study dynamical chiral
symmetry breaking on a 2-brane and a 1-brane in reduced QED_{3+1}, and on a
1-brane in reduced QED_{2+1}. Since, unlike higher dimensional gauge theories,
QED_{3+1} and QED_{2+1} are well defined, their reduced versions can serve as a
laboratory for studying dynamics in a higher dimensional brane world. The
analysis of the Schwinger-Dyson (SD) equations in these theories reveals rich
and quite nontrivial dynamics in which the conformal symmetry and its breakdown
play a crucial role. Explicit solutions of the SD equations in the
near-critical regime are obtained and the character of the corresponding phase
transition is described.


title:
Magnetic dipole moment of the $\Delta^+$(1232) from the $\gamma p \to
  \gamma \pi^0 p$ reaction

abstract:
  The $\gamma p \to \gamma \pi^0 p$ reaction in the $\Delta(1232)$-resonance
region is investigated as a method to access the $\Delta^+(1232)$ magnetic
dipole moment. The calculations are performed within the context of an
effective Lagrangian model containing both the $\Delta$-resonant mechanism and
a background of non-resonant contributions to the $\gamma p \to \gamma \pi^0 p$
reaction. Results are shown both for existing and forthcoming $\gamma p \to
\gamma \pi^0 p$ experiments. In particular, the sensitivity of unpolarized
cross sections and photon asymmetries to the $\Delta^+$ magnetic dipole moment
is displayed for those forthcoming data.


title: Observability of the Lightest CMSSM Higgs Boson at Hadron Colliders

abstract:
  We discuss the observability of the lightest neutral Higgs boson in the
constrained MSSM (CMSSM), with universal soft supersymmetry-breaking
parameters, at hadron colliders such as the Tevatron and the LHC. We take
account of the constraints on parameter space provided by LEP, the measured
rate of b to s gamma decay, the cosmological relic density Omega h^2, and the
recent measurement of g_mu - 2. We normalize products of the expected CMSSM
Higgs production cross sections and decay branching ratios (sigma B)_CMSSM
relative to those expected for a Standard Model Higgs boson of the same mass.
In the h to gamma gamma channel, we find that (sigma B)_CMSSM > 0.85 (sigma
B)_SM. In the W/t tbar + h, h to b bbar channels, we find that (sigma B)_CMSSM
\~ 1.05 (sigma B)_SM. We conclude that the lightest CMSSM Higgs boson should be
almost as easy to see as the Standard Model Higgs boson: in particular, it
should be discoverable with about 15/fb of luminosity at the Tevatron or 10/fb
of luminosity at the LHC.


title: On the Angular Dependence of the Radiative Gluon Spectrum

abstract:
  The induced momentum spectrum of soft gluons radiated from a high energy
quark produced in and propagating through a QCD medium is reexamined in the
BDMPS formalism. A mistake in our published work (Physical Review C60 (1999)
064902) is corrected. The correct dependence of the fractional induced loss
$R(\theta_{{\rm cone}})$ as a universal function of the variable
$\theta^2_{{\rm cone}} L^3 \hat q$ where $L$ is the size of the medium and
$\hat q$ the transport coefficient is presented. We add the proof that the
radiated gluon momentum spectrum derived in our formalism is equivalent with
the one derived in the Zakharov-Wiedemann approach.


title:
Remarks on the determination of the Landau gauge OPE for the Asymmetric
  three gluon vertex

abstract:
  We compute a compact OPE formula describing power corrections to the
perturbative expression for the asymmetric $\widetilde{MOM}$-renormalized
running coupling constant up to the leading logarithm. By the use of the
phenomelogical hypothesis leading to the factorization of the condensates
through a perturbative vacuum insertion, the only relevant condensate in the
game is $<A^2>$. The validity of the OPE formula is tested by searching for a
good-quality coherent description of previous lattice evaluations of
$\widetilde{MOM}$-renormalized gluon propagator and running coupling.


title: Determination of absolute neutrino masses from Z-bursts

abstract:
  Ultrahigh energy neutrinos (UHE\nu) scatter on relic neutrinos (R\nu)
producing Z bosons, which can decay hadronically producing protons (Z-burst).
We compare the predicted proton spectrum with the observed ultrahigh energy
cosmic ray (UHECR) spectrum and determine the mass of the heaviest R\nu via a
maximum likelihood analysis. Our prediction depends on the origin of the
power-like part of the UHECR spectrum: m_\nu=2.75^{+1.28}_{-0.97} eV for
Galactic halo and 0.26^{+0.20}_{-0.14} eV for extragalactic (EG) origin. The
necessary UHE\nu flux should be detected in the near future.


title:
High-Energy Proton-Proton Forward Scattering and Derivative Analyticity
  Relations

abstract:
  We present the results of several parametrizations to two different ensemble
of data on $pp$ total cross sections $\sigma_{tot}^{pp}$ at the highest
center-of-mass energies (including cosmic-ray information). The results are
statistically consistent with two distinct scenarios at high energies. From one
ensemble the prediction for the LHC ($\sqrt s = 14$ TeV) is $\sigma_{tot}^{pp}
= 113 \pm 5$ mb and from the other, $\sigma_{tot}^{pp}=140 \pm 7$ mb. From each
parametrization, and making use of derivative analyticity relations (DAR), we
determine $\rho(s)$ (ratio between the forward real and imaginary parts of the
elastic scattering amplitude). A discussion on the optimization of the DAR in
terms of a free parameter is also presented.In all cases good descriptions of
the experimental data are obtained.


title: A Comment on the Extractions of V_{ub} from Radiative Decays

abstract:
  We present a model independent closed form expression for |V_{ub}|^2/|V_{tb}
V_{ts}^*|^2, which includes the resummation of large endpoint logarithms as
well as the interference effects from the operators $O_2$ and $O_8$. We
demonstrate that the method to extract |V_{ub}| presented by the authors in
hep-ph/9909404, and modified in this letter to include interference effects, is
not just a refinement of the method introduced in hep-ph/9312311. We also
discuss the model dependence of the latter proposal. Furthermore, we show that
the resummation is not negligible and that the Landau pole does not introduce
any significant uncertainties.


title: Observability of Earth-skimming Ultra-high Energy Neutrinos

abstract:
  Neutrinos with energies above 10^8 GeV are expected from cosmic ray
interactions with the microwave background and are predicted in many
speculative models. Such energetic neutrinos are difficult to detect, as they
are shadowed by the Earth, but rarely interact in the atmosphere. Here we
propose a novel detection strategy: Earth-skimming neutrinos convert to charged
leptons that escape the Earth, and these leptons are detected in ground level
fluorescence detectors. With the existing HiRes detector, neutrinos from some
proposed sources are marginally detectable, and improvements of two orders of
magnitude are possible at the proposed Telescope Array.


title:
Two loop radion correction to $K_L$ - $K_S$ mass difference in the
  stabilised Randall-Sundrum brane world scenario

abstract:
  In the stabilised Randall-Sundrum brane world scenario, the radion can have
phenomenologically testable effects, which can be measured against precisely
measured electroweak physics data. We investigate the effect of two loop radion
corrections to $K_L$ - $K_S$ mass difference to set a bound on the radion mass
and vacuum expectation value. It is found that the leading two loop corrections
are of the order $[Log(\frac{\Lambda^2}{m_\phi^2}) ]^2$ where $\Lambda$ is the
cut-off scale ${\cal O}(\sim$TeV) and $m_\phi$ is the radion mass.


title: Comment on an invisible Higgs boson and 50 GeV neutrino

abstract:
  It has been recently suggested in hep-ph/9911535 and hep-ph/0006324 that the
fourth generation of leptons and quarks is not excluded by the precision
Z-boson measurements, provided that the mass of the fourth neutrino is around
50 GeV and that its mixing with the neutrinos of the first three generations is
negligibly small. We would like to note that in this case the decay rate of the
Standard Model Higgs boson into the pair of such neutrinos would be about two
orders of magnitude higher than than the Higgs to b-bbar rate. Thus, the
predominant decay mode of the Higgs would be invisible, which would require a
special strategy for its searches.


title:
Resolved Photon Contributions to Higgs Boson Production in gamma gamma
  Collisions

abstract:
  We study single Higgs boson production in gamma gamma collisions proceeding
via the hadronic content of the photon. These processes complement previous
studies of pair and single Higgs production at e^+e^- colliders. For SM Higgs
masses of current theoretical interest, the resolved photon contributions are
non-negligible in precision cross section measurements. The charged Higgs cross
sections are not competitive with the gamma gamma -> H^+ H^- process and at
best might offer some information about quark-Higgs couplings. Finally,
resolved photon production of the heavier Higgs bosons, H^0 and A^0 of the
MSSM, can probe regions of the SUSY parameter space that will complement other
measurements. This last process shows some promise in SUSY Higgs searches and
warrants further study.


title:
Systematic Exploration of the Neutrino Factory Parameter Space including
  Errors and Correlations

abstract:
  We discuss in a systematic way the extraction of neutrino masses, mixing
angles and leptonic CP violation at neutrino factories. Compared to previous
studies we put a special emphasis on improved statistical methods and on the
multidimensional nature of the combined fits of the nu_e -> nu_mu, \bar nu_e ->
\bar nu_mu appearance and nu_mu -> nu_mu, \bar nu_mu -> \bar nu_mu
disappearance channels. Uncertainties of all involved parameters and
statistical errors are included. We find previously ignored correlations in the
multidimensional parameter space, leading to modifications in the physics
reach, which amount in some cases to one order of magnitude. Including proper
statistical errors we determine for all parameters the improved sensitivity
limits for various baselines, beam energies, neutrino fluxes and detector
masses. Our results allow a comparison of the physics potential for different
choices of baseline and beam energy with regard to all involved parameters. In
addition we discuss in more detail the problem of parameter degeneracies in
measurements of delta_CP.


title:
Quark mass dependence of the one-loop three-gluon vertex in arbitrary
  dimension

abstract:
  The one-loop off-shell massive quark contribution to the three-gluon vertex
is calculated in an arbitrary space-time dimension. The results for all
relevant on-shell and symmetric limits are obtained directly from the general
off-shell results. The analytic structure of the results for the relevant
massive scalar integrals is also discussed.


title: B -> K(*) Kbar(*) Decays: A New Method for Measuring the CP Phase \alpha

abstract:
  We present a new method for measuring the CP phase \alpha. It requires the
measurement of the pure penguin decays Bd(t) -> K(*) Kbar(*) and B_s -> K(*)
Kbar(*). The method is quite clean: we estimate the theoretical uncertainty to
be at most 5%. By applying the method to several K(*) Kbar(*) final states,
\alpha can be extracted with a fourfold ambiguity. An additional assumption
reduces this ambiguity to twofold: {\alpha, \alpha + \pi}. Since no \pi0
detection is needed, this method can be used at hadron colliders.


title:
On propagation of high-energy photon in a medium in presence of an
  external field

abstract:
  The polarization tensor is calculated which originates from interaction of a
photon with the electron-positron field. The effects of multiple scattering of
electrons and positrons in a medium side by side with an external field are
included. The corresponding general representation of polarization tensor is
found in the form of two-dimentional integral. The both effects may be
essential for propagation of high-energy photons in oriented single crystals.


title: Equivalence Principle Tests and New Long-Range Forces

abstract:
  We discuss the possible existence of new long-range forces mediated by spin-1
or spin-0 particles. They would add their effects to those of gravity, and
could lead to apparent violations of the Equivalence Principle. Informations on
the (vector and axial) couplings of a new spin-1 U boson may be obtained from
spontaneously broken gauge invariance. The charge associated with the vector
coupling may be expressed as a linear combination of B and L. If the new force
has a finite range lambda, its intensity turns out to be proportional to
1/(lambda^2 F^2), F being the extra U(1) symmetry-breaking scale.
  Quite surprisingly, particle physics experiments can provide constraints on
such a force, even if the corresponding gauge coupling is extremely small (<<
10^-19 !). An "equivalence theorem" shows that a very light spin-1 U boson with
non-vanishing axial couplings does not in general decouple even when its gauge
coupling vanishes, but behaves as a quasimassless pseudoscalar. (This
equivalence theorem is similar to the one of supersymmetry/supergravity
theories, according to which a very light spin-3/2 gravitino might get
detectable as a quasi massless spin-1/2 goldstino, despite the extreme
smallness of Newton's gravitational constant G_N.) Searches for the radiative
production of such U bosons in psi and upsilon decays restrict the extra U(1)
symmetry-breaking scale F to be larger than the electroweak scale, providing
constraints on the intensity of the corresponding new force.


title: On the total cross section extrapolations to cosmic-ray energies

abstract:
  We analyze $pp$ total cross section data from accelerator to cosmic-ray
energies and show that the experimental information presently available
indicate two different scenarios at the highest energies. One of them
accommodates the predictions of the majority of models and the other one shows
agreement with a multiple diffraction model recently developed and improved. We
argue that these results may bring a kind of warning against some possible
precipitated attempts to constraint cosmic-ray estimations from analyzes of
accelerator data.


title: Probe of SUSY and Extra Dimensions by the Brookhaven g-2 Experiment

abstract:
  A brief review is given of $a_{\mu}=(g_{\mu}-2)/2$ as a probe of
supersymmetry and of extra dimensions. It is known since the early to mid
nineteen eightees that the supersymmetric electro-weak correction to $a_{\mu}$
can be as large or larger than the Standard Model electro-weak correction and
thus any experiment that proposes to test the Standard Model electro-weak
correction will also test the supersymmetric correction and constrain
supersymmetric models. The new physics effect seen in the Brookhaven (BNL)
experiment is consistent with these early expectations. Detailed analyses
within the well motivated supergravity unified model show that the size of the
observed difference ($a_{\mu}^{exp}-a_{\mu}^{SM}$) seen at Brookhaven implies
upper limits on sparticle masses in a mass range accessible to the direct
observation of these particles at the Large Hadron Collider. Further, analyses
also show that the BNL data is favorable for the detection of supersymmeteric
dark matter in direct dark matter searches. The effect of large extra
dimensions on $a_{\mu}$ is also discussed. It is shown that with the current
limits on the size of extra dimensions, which imply that the inverse size of
such dimensions lies in the TeV region, their effects on $a_{\mu}$ relative to
the supersymmetric contribution is small and thus extra dimensions do not
produce a serious background to the supersymmetric contribution. It is
concluded that the analysis of the additional data currently underway at
Brookhaven as well as a reduction of the hadronic error will help pin down the
scale of weak scale supersymmetry even more precisely.


title: The diquark model: New Physics effects for charm and kaon decays

abstract:
  Motivated by diquark exchange, we construct a class of extensions of the
standard model. These models can generate large CP conserving and CP violating
contributions to the doubly Cabbibo suppressed decays D^0\to K^+\pi^- without
affecting D^0-\overline{D^0} mixing, contrary to what is usually believed in
the literature. We find an interesting specific realization of these models,
which has the LR chiral structure and can induce novel density \times density
operators. It is new for non-leptonic kaon decays, and particularly, may
provide a possible solution to the \Delta I=1/2 rule and direct CP violation,
without inducing large flavour changing neutral currents.


title:
Self-consistent parametrization of the two-flavor isotropic
  color-superconducting ground state

abstract:
  Lack of Lorentz invariance of QCD at finite quark chemical potential in
general implies the need of Lorentz non-invariant condensates for the
self-consistent description of the color-superconducting ground state.
Moreover, the spontaneous breakdown of color SU(3) in this state naturally
leads to the existence of SU(3) non-invariant non-superconducting expectation
values. We illustrate these observations by analyzing the properties of an
effective 2-flavor Nambu-Jona-Lasinio type Lagrangian and discuss the
possibility of color-superconducting states with effectively gapless fermionic
excitations. It turns out that the effect of condensates so far neglected can
yield new interesting phenomena.


title: Quasi-energy-independent solar neutrino transitions

abstract:
  Current solar, atmospheric, and reactor neutrino data still allow oscillation
scenarios where the squared mass differences are all close to 10^-3 eV^2,
rather than being hierarchically separated. For solar neutrinos, this situation
(realized in the upper part of the so-called large-mixing angle solution)
implies adiabatic transitions which depend weakly on the neutrino energy and on
the matter density, as well as on the ``atmospheric'' squared mass difference.
In such a regime of ``quasi-energy-independent'' (QEI) transitions,
intermediate between the more familiar ``Mikheyev-Smirnov-Wolfenstein'' (MSW)
and energy-independent (EI) regimes, we first perform analytical calculations
of the solar nu_e survival probability at first order in the matter density,
beyond the usual hierarchical approximations. We then provide accurate,
generalized expressions for the solar neutrino mixing angles in matter, which
reduce to those valid in the MSW, QEI and EI regimes in appropriate limits.
Finally, a representative QEI scenario is discussed in some detail.


title: Observability of MSSM Higgs bosons decaying to sparticles at the LHC

abstract:
  The possibility is discussed to observe the sparticle decay modes of the
heavy MSSM Higgs bosons at the Large Hadron Collider. We focus on the heavy
neutral Higgses, and argue that their decay into neutralinos may access an
interesting region in the MSSM parameter space up to masses around 450 GeV for
low and intermediate values of tan beta. If neutralinos and sleptons are light
enough, this channel - leading to a four lepton final state topology - can
complement the reach of the SM channels.


title: Q Qbar g contribution to diffractive J/psi electroproduction

abstract:
  We study the diffractive electroproduction of quarkonia from
quark-antiquark-gluon states in the photon wave function. We show that these
states contribute to the leading-power and leading-logarithm level. We suggest
the measurement of J/psi production via inelastic diffraction to study
color-transparency and color-opacity effects in the diffractive gluon
distribution.


title: Astrophysical Constraints on Modifying Gravity at Large Distances

abstract:
  Recently, several interesting proposals were made modifying the law of
gravity on large scales, within a sensible relativistic formulation. This
allows a precise formulation of the idea that such a modification might account
for galaxy rotation curves, instead of the usual interpretation of these curves
as evidence for dark matter. We here summarize several observational
constraints which any such modification must satisfy, and which we believe make
more challenging any interpretation of galaxy rotation curves in terms of new
gravitational physics.


title: Universal Extra Dimensions and b -> s gamma

abstract:
  We analyze the effect of flat universal extra dimensions (i.e., extra
dimensions accessible to all SM fields) on the process b -> s gamma. With one
Higgs doublet, the dominant contribution at one-loop is from Kaluza-Klein (KK)
states of the charged would-be-Goldstone boson (WGB) and of the top quark. The
resulting constraint on the size of the extra dimension is comparable to the
constraint from T parameter. In two-Higgs doublet model II, the contribution of
zero-mode and KK states of physical charged Higgs can cancel the contribution
from WGB KK states. Therefore, in this model, there is no constraint on the
size of the extra dimensions from the process b -> s gamma and also the
constraint on the mass of the charged Higgs from this process is weakened
compared to 4D. In two Higgs doublet model I, the contribution of the zero-mode
and KK states of physical charged Higgs and that of the KK states of WGB are of
the same sign. Thus, in this model and for small tan beta, the constraint on
the size of the extra dimensions is stronger than in one Higgs doublet model
and also the constraint on the mass of the charged Higgs is stronger than in
4D.


title: In-medium pion weak decay constants

abstract:
  In nuclear matter, the pion weak decay constant is separated into the two
components $f_t, f_s$ corresponding to the time and space components of the
axial-vector current. Using QCD sum rules, we compute the two decay constants
from the pseudoscalar-axial vector correlation function in the matter $i \int
d^4x~ e^{ip\cdot x} < \rho| T[{\bar d}(x) i \gamma_5 u (x)~ {\bar u}(0)
\gamma_\mu \gamma_5 d (0)] | \rho>$. It is found that the sum rule for $f_t$
satisfies the in-medium Gell-Mann--Oakes--Renner (GOR) relation precisely while
the $f_s$ sum rule does not. The $f_s$ sum rule contains the non-negligible
contribution from the dimension 5 condensate $<{\bar q} i D_0 iD_0 q >_N +
{1\over 8} < {\bar q} g_s \sigma \cdot {\cal G} q >_N$ in addition to the
in-medium quark condensate. Using standard set of QCD parameters and ignoring
the in-medium change of the pion mass, we obtain $f_t =105$ MeV at the nuclear
saturation density. The prediction for $f_s$ depends on values of the dimension
5 condensate and on the Borel mass. However, the OPE constrains that $f_s/f_t
\ge 1 $, which does not agree with the prediction from the in-medium chiral
perturbation theory. Depending on the value of the dimension 5 condensate,
$f_s$ at the saturation density is found to be in the range $ 112 \sim 134$ MeV
at the Borel mass $M^2 \sim 1$ GeV$^2$.


title:
Nucleation versus Spinodal decomposition in a first order quark hadron
  phase transition

abstract:
  We investigate the scenario of homogeneous nucleation for a first order
quark-hadron phase transition in a rapidly expanding background of quark gluon
plasma. Using an improved preexponential factor for homogeneous nucleation
rate, we solve a set of coupled equations to study the hadronization and the
hydrodynamical evolution of the matter. It is found that significant
supercooling is possible before hadronization begins. This study also suggests
that spinodal decomposition competes with nucleation and may provide an
alternative mechanism for phase conversion particularly if the transition is
strong enough and the medium is nonviscous. For weak enough transition, the
phase conversion may still proceed via homogeneous nucleation.


title:
Correlations of errors in measurements of CP violation at neutrino
  factories

abstract:
  Using $\Delta\chi^2$ which is defined by the difference of the number of
events with the CP phase $\delta$ and the hypothetical one with $\delta=0$, we
discuss correlations of errors of the CP phase and other oscillation parameters
as well as the matter effect in measurements at neutrino factories. By varying
the oscillation parameters and the normalization of the matter effect, we
evaluated the data size required to reject a hypothesis with $\delta=0$ at
3$\sigma$CL. The optimum muon energy and the baseline depends on the magnitude
of $\theta_{13}$, the background fraction, the uncertainty of the normalization
of the matter effect, but in general lie in the ranges 20GeV $\lesssim
E_\mu\lesssim$ 50GeV, 1000km$\lesssim L\lesssim$3000km. If we assume that the
uncertainty of the matter effect is as large as 20% then the optimum values may
be modified to $E_\mu\lesssim$ 10GeV, $L\lesssim$1000km due to the strong
correlation of $\delta$ and the matter effect. We show analytically that
sensitivity to CP violation is lost for $E_\mu\ll$ 10GeV or for $E_\mu\gg$
50GeV. We also discuss the possibility of measuring CP violation at the
upgraded JHF experiment by taking all the error correlations into account, and
show that it is possible to demonstrate $\delta\ne0$ at 3$\sigma$CL for
$\theta_{13}\gtrsim 3^\circ$.


title: New data and the hard pomeron

abstract:
  New structure-function data are in excellent agreement with the existence of
a hard pomeron, with intercept about 1.4. It gives a very economical
description of the data. Having fixed 2 parameters from the data for the
real-photon cross section $\sigma^{\gamma p}$, we need just 5 further
parameters to fit the data for $F_2(x,Q^2)$ with $x\leq 0.001$. The available
data range from $Q^2=0.045$ to 35 GeV$^2$. With guesses consistent with
dimensional counting for the $x$ dependences of our three separate terms, the
fit extends well to larger $x$ and to $Q^2=5000$ GeV$^2$. With no additional
parameters, it gives a good description of data for the charm structure
function $F_2^c(x,Q^2)$ from $Q^2=0$ to 130 GeV$^2$. The two pomerons also give
a good description of both the $W$ and the $t$ dependence of $\gamma p\to
J/\psi p$.


title: The 2+2 and 3+1 Four-Family Neutrino Mixing at the Neutrino Factory

abstract:
  We upgrade the study of the physical reach of a Neutrino Factory in the Four
Family Neutrino Mixing scenario taking into account the latest LSND results
that points out how the 3+1 scheme cannot be completely ruled out within the
present experimental data (although the 2+2 scheme is still the preferred
choice when four neutrinos are considered). A detailed comparison of the
physical reach of the $\nu$-factory in the two schemes is given, with similar
results for the sensitivity to the mixing angles. Huge CP-violating effects can
be observed in both schemes with a near, O(10) Km, detector of O(10) Kton size
in the $\nu_\mu \to \nu_\tau$ channel. A smaller detector of 1 Kton size can
still observe very large effects in this channel.


title:
Pair Production of Neutral Higgs Bosons through Noncommutative QED
  Interactions at Linear Colliders

abstract:
  We study the feasibility of detecting noncommutative (NC) QED through neutral
Higgs boson (H) pair production at linear colliders (LC). This is based on the
assumption that H interacts directly with photon in NCQED as suggested by
symmetry considerations and strongly hinted by our previous study on
\pi^0-photon interactions. We find the following striking features as compared
to the standard model (SM) result: (1) generally larger cross sections for an
NC scale of order 1 TeV; (2) completely different dependence on initial beam
polarizations; (3) distinct distributions in the polar and azimuthal angles;
and (4) day-night asymmetry due to the Earth's rotation. These will help to
separate NC signals from those in the SM or other new physics at LC. We
emphasize the importance of treating properly the Lorentz noninvariance problem
and show how the impact of the Earth's rotation can be used as an advantage for
our purpose of searching for NC signals.


title: Precision measurements at a muon collider

abstract:
  This contribution describes precision width measurements that could be done
at a muon collider for very narrow resonances as the Higgs or a possible
pseudogoldstone boson, or for almost degenerate resonances as the A0 and H0 in
the MSSM for large values of tan\beta.


title: Pade Estimate of QCD's Infrared Boundary

abstract:
  A mass scale $\mu_c$ representing the boundary between effective theories of
strong interactions and perturbative QCD (infrared and ultraviolet regimes)
exists when the $\beta$-function is characterized by a simple pole. This
behaviour, which is known to occur in N=1 supersymmetric Yang-Mills theories,
leads to an infrared attractor in the evolution of the coupling constant, with
the mass scale $\mu_c$ of the attractor providing a natural boundary between
the infrared and ultraviolet regimes. It is demonstrated that [2|2], [3|1] and
[1|3] Pade-approximant versions of the three-flavour QCD $\beta$-function each
contain a simple pole corresponding to such an infrared attractor. All three
approximants, separately considered, are seen to lead to nearly equivalent
estimates for the mass scale $\mu_c$.


title: Vacuum Saturation Hypothesis and QCD Sum Rules

abstract:
  The accuracy of the vacuum saturation hypothesis is discussed using the
examples of vacuum expectation values of four-quark operators and the parameter
$B$, which determines the short-distance contribution to the $K^0 - \bar K^0$
mixing. Note added: The approach based on sum rules in position (x-)space as
elaborated in the paper is relevant and useful tool for the current
phenomenology. In particular, it provides the unique possibility of direct
non-perturbative estimation of the VEV's of four-quark operators renormalized
in any scheme, including the MSbar one.


title:
Nonperturbative Vacuum Effect in the Quantum Field Theory of Meson
  Mixing

abstract:
  Replacing the perturbative vacuum by the nonperturbative vacuum, we extend a
recent development of a quantum field theoretic framework for scalar and
pseudoscalar meson mixing. The unitary inequivalence of the Fock space of base
(unmixed) eigenstates and the physical mixed eigenstates is investigated and
the flavor vacuum state structure is explicitly found. This is exploited to
develop formulas for two flavor boson oscillations in systems of arbitrary
boson occupation number. We apply these formulas to analyze the mixing of eta
with eta' and comment on the other meson-mixing systems. In addition, we
consider the mixing of boson coherent states, which may have future
applications in the construction of meson lasers.


title: Quantum collisions of finite-size ultrarelativistic nuclei

abstract:
  We show that the boost variable, the conjugate to the coordinate rapidity,
which is associated with the center-of-mass motion, encodes the information
about the finite size of colliding nuclei in a Lorentz-invariant way. The
quasi-elastic forward color-changing scattering between the quantum boost
states rapidly grows with the total energy of the collision and leads to an
active breakdown of the color coherence at the earliest moments of the
collision. The possible physical implications of this result are discussed.


title: On the neutral Higgs boson masses in the MSSM for arbitrary stop mixing

abstract:
  We compute the O(alpha_t alpha_s) two-loop corrections to the neutral Higgs
boson masses in the Minimal Supersymmetric extension of the Standard Model. An
appropriate use of the effective potential allows us to obtain simple
analytical formulae, valid for arbitrary values of mA and of the mass
parameters in the stop sector. We elucidate some subtleties of the effective
potential calculation, and find full agreement with the numerical output of the
existing diagrammatic calculation. We discuss in detail the limit of heavy
gluino.


title: SUSY-QCD decoupling properties in H+ -> t \bar b decay

abstract:
  The SUSY-QCD radiative corrections to the \Gamma (H+ -> t \bar b) partial
decay width are analyzed within the Minimal Supersymmetric Standard Model at
the one-loop level, {\mathcal O}(\alpha_s), and in the decoupling limit. We
present the analytical expressions of these corrections in the large SUSY
masses limit and study the decoupling behaviour of these corrections in various
limiting cases. We find that if the SUSY mass parameters are large and of the
same order, the one loop SUSY-QCD corrections {\it do not decouple}. The
non-decoupling contribution is enhanced by \tan \beta and therefore large
corrections are expected in the large \tan \beta limit. In contrast, we also
find that the SUSY-QCD corrections decouple if the masses of either the squarks
or the gluinos are separately taken large.


title:
A gauge-invariant subtraction technique for non-inclusive observables in
  QCD

abstract:
  Using the electromagnetic form factor of a quark as a working example, we
describe a subtraction technique to treat infrared sensitive regions in
non-inclusive processes.


title: The endpoint region in radiative quarkonia decays

abstract:
  We consider the inclusive radiative decays quarkonium -> gamma + hadrons and
examine the effects of soft QCD radiation on the photon energy spectrum near
the endpoint.


title: Selectron Studies at e-e- and e+e- Colliders

abstract:
  Selectrons may be studied in both e-e- and e+e- collisions at future linear
colliders. Relative to e+e-, the e-e- mode benefits from negligible backgrounds
and \beta threshold behavior for identical selectron pair production, but
suffers from luminosity degradation and increased initial state radiation and
beamstrahlung. We include all of these effects and compare the potential for
selectron mass measurements in the two modes. The virtues of the e-e- collider
far outweigh its disadvantages. In particular, the selectron mass may be
measured to 100 MeV with a total integrated luminosity of 1 fb^-1, while more
than 100 fb^-1 is required in e+e- collisions for similar precision.


title:
Solutions of the atmospheric, solar and LSND neutrino anomalies from TeV
  scale quark-lepton unification

abstract:
  There is a unique $SU(4) \otimes SU(2)_L \otimes SU(2)_R$ gauge model which
allows quarks and leptons to be unified at the TeV scale. It is already known
that the neutrino masses arise radiatively in the model and are naturally
light. We study the atmospheric, solar and LSND neutrino anomalies within the
framework of this model.


title: The bubbles of matter from multiskyrmions

abstract:
  The multiskyrmions with large baryon number B given by rational map (RM)
ansaetze can be described reasonably well within the domain wall approximation,
or as spherical bubbles with energy and baryon number density concentrated at
their boundary. A special class of profile functions is considered
approximating the true profile and domain wall behaviour at the same time. An
upper bound is obtained for the masses of RM multiskyrmions which is close to
the calculated masses, especially at large B. The gap between rigorous upper
and lower bounds for large B multiskyrmions is less than 4%. The basic
properties of such bubbles of matter are investigated, some of them being of
universal character, i.e. they do not depend on baryon number of configuration
and on the number of flavors. As a result, the lagrangian of the Skyrme type
models provides field theoretical realization of the bag model of special kind.


title: Model independent sum rules for B-> pi K decays

abstract:
  We provide a set of sum rules relating CP-averaged branching ratios and
CP-asymmetries of the $B \to \pi K$ modes. They prove to be useful as a
mechanism to `test' experimental data given our expectations of the size of
isospin breaking. A set of observables emerges providing a simpler
interpretation of data in terms of isospin breaking. Moreover, the derivation
is done in a completely model independent way, i.e., they can accommodate also
New Physics contributions.


abstract:
  Strangeness production in heavy ion collisions is discussed in a broad energy
range from SIS to RHIC. %We emphasize that in the In the whole energy range
particle yields are showing high level of chemical equilibration which can be
described by the unified freezeout conditions of fixed energy/particle $\simeq
1$GeV. The statistical model within the canonical formulation of strangeness
conservation provides a framework to describe the observed enhancement of
(multi)strange particles from p+A to A+A collisions measured at the SPS energy
and predicts that this enhancement should be larger for decreasing collision
energy. However, only at the SPS and RHIC chemical freezeout temperature is
consistent within error with the critical value required for deconfinement and
simultaneously strangeness is uncorrelated and distributed in the whole volume
of the fireball.


title: Neutrino Mass Spectrum and Future Beta Decay Experiments

abstract:
  We study the discovery potential of future beta decay experiments on searches
for the neutrino mass in the sub-eV range, and, in particular, KATRIN
experiment with sensitivity $m > 0.3$ eV. Effects of neutrino mass and mixing
on the beta decay spectrum in the neutrino schemes which explain the solar and
atmospheric neutrino data are discussed. The schemes which lead to observable
effects contain one or two sets of quasi-degenerate states. Future beta decay
measurements will allow to check the three neutrino scheme with mass
degeneracy, moreover, the possibility appears to measure the CP-violating
Majorana phase. Effects in the four neutrino schemes which can also explain the
LSND data are strongly restricted by the results of Bugey and CHOOZ oscillation
experiments: Apart from bending of the spectrum and the shift of the end point
one expects appearance of small kink of ($ < 2% $) size or suppressed tail
after bending of the spectrum with rate below 2 % of the expected rate for zero
neutrino mass. We consider possible implications of future beta decay
experiments for the neutrino mass spectrum, the determination of the absolute
scale of neutrino mass and for establishing the nature of neutrinos. We show
that beta decay measurements in combination with data from the oscillation and
double beta decay experiments will allow to establish the structure of the
scheme (hierarchical or non-hierarchical), the type of the hierarchy or
ordering of states (normal or inverted) and to measure the relative
CP-violating phase in the solar pair of states.


title:
Indirect Signatures of CP Violation in the Processes $\gamma \gamma \to
  \gamma \gamma$, $\gamma Z$, and $ZZ$

abstract:
  This paper studies the utility of the processes $\gamma \gamma \to \gamma
\gamma$, $\gamma Z$, and $ZZ$ in searching for sources of CP violation arising
from energy scales beyond the production thresholds of planned future
colliders. In the context of an effective Lagrangian approach we consider the
most general set of CP odd SU(2) $\times$ U(1) operators that give rise to
genuinely quartic gauge boson couplings which can be probed in $2 \to 2$
scattering processes at a $\gamma \gamma $ collider. We study each process in
detail, emphasizing the complementary information that is obtained by varying
the initial beam polarizations. Finally, we compare our results to other
constraints in the literature on CP odd gauge boson interactions and quartic
gauge boson couplings; the search reaches obtained here are typically stronger
and nicely complement previous studies which have focused primarily on $W$
boson, top quark, or Higgs production.


title: Mixing among light scalar mesons and L=1 q\bar{q} scalar mesons

abstract:
  Following the re-establishment of the \sigma(600) and the \kappa(900), the
light scalar mesons a_0(980) and f_0(980) together with the \sigma(600) and the
\kappa(900) are considered as the chiral scalar partner of pseudoscalar nonet
in SU(3) chiral symmetry, and the high mass scalar mesons a_0(1450),
K^*_0(1430), f_0(1370) and f_0(1710) turned out to be considered as the L=1
q\bar{q} scalar mesons. We assume that the high mass of the L=1 q\bar{q} scalar
mesons is caused by the mixing with the light scalar mesons. For the structure
of the light scalar mesons, we adopted the qq\bar{q}\bar{q} model in order to
explain the "scalar meson puzzle". The inter-mixing between the light scalar
nonet and the high mass L=1 q\bar{q} nonet and the intra-mixing among each
nonet are analyzed by including the glueball into the high mass scalar nonet.


title:
Scalar top quarks at the Run II of the Tevatron in the high \tan\beta
  regime

abstract:
  We discuss the decays of the lightest scalar top quark $\tilde{t}_1$ in the
Minimal Supersymmetric extension of the Standard Model and show that the final
state $b\tau \nu_\tau \chi_1^0$, where $\chi_1^0$ is the lightest
supersymmetric particle, can be dominant in a significant area of the parameter
space, in particular in the high $\tan \beta$ regime. We then analyze the
prospects for discovering relatively light scalar top quarks accessible at the
Tevatron Run II in the $b\tau$ and missing energy channel.


title: A Study of Heavy-Light Mesons on the Transverse Lattice

abstract:
  We present results from a study of meson spectra and structure in the limit
where one quark is infinitely heavy. The calculations, based on the framework
of light-front QCD formulated on a transverse lattice, are the first
non-perturbative studies of B-mesons in light-front QCD. We calculate the
Isgur-Wise form factor, light-cone distribution amplitude, the heavy-quark
parton distribution function and the leptonic decay constant of B-mesons.


title: Long-Range Coulomb Forces in DIS: Missed Radiative Corrections?

abstract:
  The Born approximation, one photon exchange, used for DIS is subject to
virtual radiative corrections which are related to the long-range Coulomb
forces. They may be sizeable for heavy nuclei since Z\alpha is not a small
parameter. So far these corrections are known only for two processes, elastic
scattering and bremsstrahlung on the Coulomb field of a point-like target.
While the former amplitude acquires only a phase, in the latter case the cross
section is modified also. Although the problem of Coulomb corrections for DIS
on nuclei is extremely difficult, it should be challenged rather than 'swept
under the carpet'. The importance of these radiative corrections is questioned
in present paper. We show that in the simplest case of a constant hadronic
current the Coulomb corrections provide a phase to the Born amplitude,
therefore the cross section remains the same. Inclusion of more realistic
hadronic dynamics changes this conclusion. The example of coherent production
of vector mesons off nuclei reveals large effects. So far a little progress has
been made deriving exact lepton wave functions in the Coulomb field of an
extended target. Employing available results based on the first-order
approximation in Z\alpha, we conclude that the Coulomb corrections are still
important for heavy nuclei. We also consider an alternative approach for
extended nuclear targets, the eikonal approximation, which we demonstrate to
reproduce the known exact results for Coulomb corrections. Calculating
electroproduction of vector mesons we again arrive at a large deviation from
the Born approximation. We conclude that one should accept with caution the
experimental results for nuclear effects in DIS based on analyses done in the
Born approximation.


title:
Muon transverse polarization in the $K_{l2\gamma}$ process within the SM
  and three Higgs doublets Weinberg model

abstract:
  We consider two possible sources of the $T$-violating muon transverse
polarization in the process $K^+ \to \mu^+
  \nu \gamma$: electromagnetic final state interaction in the SM and
contribution due to charged-Higgs exchange diagrams in the framework of the
Weinberg three doublets model. It is shown that at the one-loop level of the SM
the muon transverse polarization, $P_T^{SM}$, varies within $(0.0 \div 1.1
\cdot 10^{-3})$ in the Dalitz plot region. Averaged value of the muon
polarization, $<P^{SM}_T>$, in the kinematic region of $E_\gamma \geq 20$ MeV
is equal to $4.76\cdot 10^{-4}$. In the case of the model with three Higgs
doublets the muon transverse polarization is calculated as a function of
charged Higgs masses, imaginary part of the Yukawa coupling constants product
and vacuum expectation values of the Higgs doublets. The averaged value of the
transverse polarization in the Weinberg model is $<P^{Higgs}_T > = - 6.62 \cdot
10^{-5}$. Perspectives to probe the effect caused by the charged Higgs exchange
diagrams in planned kaon experiments are discussed.


title: Symplectic vs pseudo-Euclidean space-time with extra dimensions

abstract:
  It is conjectured that the symplectic structure of space-time is superior to
the metric one. Instead of the commonly adopted pseudo-orthogonal groups
SO(1,d-1), d\ge4, the complex symplectic ones Sp(2l,C), l\ge1 are proposed as
the local structure groups of the extended space-time. A discrete series of the
metric space-times of the particular dimensionalities d=4l^2 and signatures,
with l(2l-1) time and l(2l+1) spatial directions, defined over the set of the
Hermitian second-rank spin-tensors is proposed as an alternative to the
pseudo-Euclidean space-times with extra dimensions. The one-dimensional
time-like direction remaining invariant under fixed boosts makes it possible
the non-relativistic causality description despite the presence of extra times.


title: Constrained Standard Model from Extra Dimension

abstract:
  A five dimensional supersymmetric model is constructed which reduces to the
one Higgs-doublet standard model at low energies. The radiative correction to
the Higgs potential is finite and calculable, allowing the Higgs mass
prediction of 127 \pm 8 GeV. The physical reasons for this finiteness are
discussed in detail. The masses of the superparticles and the Kaluza-Klein
excitations are also predicted. The lightest superparticle is a top squark of
mass 197 \pm 20 GeV.


title:
SUSY Dark Matter Detection, The Directional Rate and the Modulation
  effect

abstract:
  The detection of the theoretically expected dark matter is central to
particle physics and cosmology. Current fashionable supersymmetric models
provide a natural dark matter candidate which is the lightest supersymmetric
particle (LSP). Such models combined with fairly well understood physics like
the quark substructure of the nucleon and the nuclear structure (form factor
and/or spin response function), permit the evaluation of the event rate for
LSP-nucleus elastic scattering. The thus obtained event rates are, however,
very low or even undetectable. So it is imperative to exploit the modulation
effect, i.e. the dependence of the event rate on the earth's annual motion.
Also it is useful to consider the directional rate, i.e its dependence on the
direction of the recoiling nucleus. In this paper we study such a modulation
effect both in non directional and directional experiments. We calculate both
the differential and the total rates using both isothermal, symmetric as well
as only axially asymmetric, and non isothermal, due to caustic rings, velocity
distributions. We find that in the symmetric case the modulation amplitude is
small. The same is true for the case of caustic rings. The inclusion of
asymmetry, with a realistic enhanced velocity dispersion in the galactocentric
direction, yields an enhanced modulation effect, especially in directional
experiments.


title: SUSY Cold Dark Matter Detection at large tan\beta

abstract:
  We study the direct detection rate for SUSY cold dark m atter (CDM) predicted
by the minimal supersymmetric standard model with universal boundary conditions
and large values for tan\beta. The relic abundance of the lightest
supersymmetric particle (LSP), assumed to be approximately a bino, is obtained
by including its coannihilations with the next-to-lightest supersymmetric
particle (NLSP), which is the lightest s-tau. We find detectable rates in the
currently planned experiments for a sector of the parameter space consistent
with the cosmological constraint on the LSP relic abundance and the ones
imposed by b->s gamma and the Higgs searches.


title: Fourth generation effects on the rare $B\to K^{*}\nu\bar{\nu}$ decay

abstract:
  If the fourth generation fermions exist, the new quarks could influence the
branching ratio of the rare $B\to K^{*}\nu\bar{\nu}$ decay. Two possible
solutions of the fourth generation CKM factor
$(V^{*}_{\acute{t}s}V_{\acute{t}b})^(\pm)$ are obtained as a function of the
new $\acute{t}$-quark mass $(m_{\acute{t}})$ from the experimental results of
the $B\to X_{s}\gamma$ together with the semileptonic decay $B\to
X_{c}\ell\bar{\nu}$. The branching ratio of the decay $B\to K^{*}\nu\bar{\nu}$
in the two cases is estimated. In one case, a significant enhancement to the
branching ratio of the decay $B\to K^{*}\nu\bar{\nu}$ over the SM is recorded,
while results are almost same in another case. If a fourth generation should
exist in nature and nature chooses the former case, this B meson decay could be
a good probe to the existence of the fourth generation, or perhaps a signal for
a new physics.


title:
CP Violation via Top Quark Anomalous Interaction at the Fermilab
  Tevatron

abstract:
  Expecting the forthcoming experiment at the upgraded Fermilab Tevatron, we
calculated CP-violating polarization asymmetry of t t-bar,
  A_{CP}= [sigma(p p-bar --> t(-) t-bar(-) X) - sigma(p p-bar --> t(+) t-bar(+)
X)]/ sigma(p p-bar --> t t-bar X), due to possible anomalous chromomagnetic
(kappa) and chromoelectric (tilde{kappa}) couplings of the gluon to the top
quark. Since kappa and tilde{kappa} are sensitive to a contribution from new
physics beyond standard model, this observable is useful to search for a signal
of new physics. It was seen that the magnitude of A_{CP} depends only on
Im(tilde{kappa) and Im(kappa^* tilde{kappa}). Futhermore, we found that when
|Im(kappa^* tilde{kappa})|>0.5, one can possibly detect the CP-violation effect
as a signal of new physics even if the magnitude of Im(tilde{kappa) is zero.


title: Radiative corrections to bound-state properties in QED

abstract:
  This talk summarizes some results on bound-state properties obtained since
the previous (1998) RADCOR meeting. Recent results on radiative corrections to
positronium decay width and the $g$-factor of a bound electron are described. A
new approach to evaluating recoil corrections in systems consisting of
particles with different masses is discussed.


title:
A new three flavor oscillation solution of the solar neutrino deficit in
  R-parity violating supersymmetry

abstract:
  We present a solution of the solar neutrino deficit using three flavors of
neutrinos within the R-parity non-conserving supersymmetric model. In vacuum,
mass and mixing is restricted to the nu(mu)-nu(tau) sector only, which we
choose in consistency with the requirements of the atmospheric neutrino
anomaly. The nu(e) is massless and unmixed. The flavor changing and flavor
diagonal neutral currents present in the model and an energy-dependent
resonance-induced nu(e)-nu(mu) mixing in the sun result in the new solution to
the solar neutrino problem. The best fit to the solar neutrino rates and
spectrum (1258-day SK data) requires a mass square difference of 10^{-5} eV^2
in vacuum between the two lightest neutrinos. This solution cannot accommodate
a significant day-night effect for solar neutrinos.


title: Quartic anomalous couplings at LEP

abstract:
  The search for quartic anomalous gauge couplings at LEP requires appropriate
predictions for the radiative processes e+ e- \to \nu\bar\nu \gamma\gamma, e+
e- \to q\bar{q}\gamma\gamma and e+ e- \to 4 fermions+\gamma. Matrix elements
are exactly computed at the tree level, and the effects of anomalous couplings
and initial-state radiation are included. Comparisons with results and
approximations existing in the literature are shown and commented. Improved
versions of the event generators NUNUGPV and WRAP are made available for
experimental analysis.


title: Isolated prompt photon photoproduction at NLO

abstract:
  We present a full next-to-leading order code to calculate the photoproduction
of prompt photons. The code is a general purpose program of partonic event
generator type with large flexibility. We study the possibility to constrain
the photon structure functions and comment on isolation issues. A comparison to
ZEUS data is also shown.


title: Small-x Physics and Forward Jet Production at THERA

abstract:
  We discuss some aspects of forward jet production as a signature for small
$x$ physics at THERA energies.


title:
Study of $\gamma\pi \to \pi\pi$ below 1 GeV using Integral Equation
  Approach

abstract:
  The scattering of $\gamma \pi \to \pi \pi$ is studied using the axial
anomaly, elastic unitarity, analyticity and crossing symmetry. Using the
technique to derive the Roy's equation, an integral equation for the P-wave
amplitude is obtained in terms of the strong P-wave pion pion phase shifts. Its
solution is obtained numerically by an iteration procedure using the starting
point as the solution of the integral equation of the Muskelshsvilli-Omnes
type. It is, however, ambiguous and depends sensitively on the second
derivative of the P-wave amplitude at $s=m_\pi^2$ which cannot directly be
measured.


title: Fermion masses and mixings in gauge theories

abstract:
  The recent evidence for neutrino oscillations stimulate us to discuss again
the problem of fermion masses and mixings in gauge theories. In the standard
model, several forms for quark mass matrices are equivalent. They become
ansatze within most extensions of the standard model, where also relations
between quark and lepton sectors may hold. In a seesaw framework, these
relations can constrain the scale of heavy neutrino mass, which is often
related to the scale of intermediate or unification gauge symmetry. As a
consequence, two main scenarios arise. Hierarchies of masses and mixings may be
explained by broken horizontal symmetries.


title: Final reheating temperature on a single brane

abstract:
  We make a generic remark on thermal history of a single brane cosmology in
models with an infinitely large single extra dimension. We point out that the
reheat temperature of the Universe is bounded by an excess production of
gravitons from the thermal bath. The actual bound is given by the brane
tension. If the initial temperature of the Universe is larger than this bound,
then an efficient graviton production shall prevail. However, the brane cools
down gradually as the Kaluza-Klein gravitons take the energy in excess away
from the brane. The cooling continues until the radiation dominated phase is
restored, which occurs before the Big Bang Nucleosynthesis. We argue whatsoever
be the early evolution of the Universe, the final radiation dominated phase
always starts after the Universe transits from non-conventional era to the
standard cosmological era.


title: Heavy Quark Production Measurements at THERA

abstract:
  The total cross sections of charm and beauty production at a future
high-energy ep collider, THERA, are expected to increase by factors of three
and five, respectively, as compared to HERA. Heavy quarks can be measured at
THERA in wide ranges of transverse momenta and Q^2 values, thereby providing a
solid basis for testing the perturbative QCD calculations. The charm and beauty
contributions to the proton structure can be probed at THERA at ~1 order of
magnitude smaller Bjorken x values with respect to those at HERA. Charm
production in the process of photon-gluon fusion at THERA can serve for the
determination of the gluon structure of the proton in the as yet unexplored
kinematic range 10^{-5} < x_g < 10^{-4}. The cross section of charm production
in charged current at THERA is ~1 order of magnitude larger than that at HERA.


title: Some Uses of Neutrino Telescopes

abstract:
  We imagine that large neutrino telescopes will be built and that distant
neutrino sources of high energies and fluxes exist. Some possible, if
difficult, uses to which they might be put are described; including (i)
detecting neutrino mass-mixing possibly upto delta m^2 of 10^{-16}eV^2; (ii)
measuring neutrino cross-sections at PeV energies; (iii) detecting relic
neutrinos; (iv) doing cosmology with neutrinos and (v) SETI with neutrinos.


title: Higgs Sector Radiative Corrections and s-Channel Production

abstract:
  Higgs boson mass sum rules of supersymmetric models offer attractive targets
for precision tests at future muon colliders. These sum rules involve the gauge
boson masses as well as the masses of the Higgs boson states which can be
precisely measured in the $s$-channel production process at a muon collider.
These measurements can sensitively probe radiative corrections to the Higgs
boson masses as well as test for CP-violation and nonminimality of the Higgs
sector.


title: Higgs + 2 jets via gluon fusion

abstract:
  Real emission corrections to gg -> H, which lead to H+2 jet events, are
calculated at order alpha_s^4. Contributions include top-quark triangles, boxes
and pentagon diagrams and are evaluated analytically for arbitrary top mass
m_t. This new source of H+2 jet events is compared to the weak-boson fusion
cross section for a range of Higgs boson masses. The heavy top-mass
approximation appears to work well for intermediate Higgs-boson masses,
provided that the transverse momenta of the final-state partons are smaller
than the top-quark mass.


title:
Anomalous single top quark production at the THERA and LinacxLHC based
  gamma-p colliders

abstract:
  Single production of t-quarks at the THERA and LinacxLHC based gamma-p
colliders via anomalous gamma-u-t and gamma-c-t couplings have been studied. We
show that gamma-p colliders will be a powerful tool for searching for the
anomalous couplings.


title: Nonleptonic kaon decays: theory vs. experiment

abstract:
  A review of the present experimental status of the rates and the Dalitz-plot
slope parameters in CP conserving K->2\pi and K->3\pi decays is given. The
corresponding isospin amplitudes have been determined by a common fit to the
recent experimental data and have been used as an input to a consequent fit
based on the constraints from O(p^4) chiral lagrangian. It has been found that
the constraints of the chiral fit are well satisfied by the experimental data,
allowing to estimate the weak coupling constants and to predict the quadratic
amplitudes in K->3\pi decays and the one-loop strong rescattering phases. The
consistency of the obtained weak coupling constants with weak resonance models
has been also considered.


title: U(3) chiral perturbation theory with infrared regularization

abstract:
  We include the eta-prime in chiral perturbation theory without employing
1/N_c counting rules. The method is illustrated by calculating the masses and
decay constants of the Goldstone boson octet (pions, kaons, eta) and the
singlet eta-prime up to one-loop order. The effective Lagrangian describing the
interactions of the eta-prime with the Goldstone boson octet is presented up to
fourth chiral order and the loop integrals are evaluated using infrared
regularization, which preserves Lorentz and chiral symmetry.


title:
Neutrino asymmetry generation in the early Universe (from active-sterile
  neutrino oscillations)

abstract:
  Neutrino asymmetry generation from active-sterile neutrino oscillations in
the early Universe has different important cosmological effects. We discuss its
basic features and present recent results on the borders of the generation for
mixing angles $\sin^2 2\theta_0\leq 10^{-7}$.


title:
Adiabatic and isocurvature fluctuations of Affleck-Dine field in D-term
  inflation model

abstract:
  We reconsider fluctuations of Affleck-Dine (AD) field in a D-term inflation
model. Contrary to the previous analysis, we find that the spectrum of the
adiabatic fluctuations is almost scale invariant even if the AD field has a
large initial value. Furthermore, we study the isocurvature fluctuations of the
AD field and estimate the ratio of the isocurvature to adiabatic power
spectrum. The dynamics of the inflaton and AD fields sets the upper bound for
the value of the AD field, leading to a lower limit for isocurvature
perturbation. It is shown that the recent Cosmic Microwave Background data give
a constraint on the D-term inflation and the AD field.


title: Photoproduction of prompt photons at NLO

abstract:
  A numerical program to calculate the photoproduction of prompt photons is
presented. The code includes full next-to-leading order corrections to all
subprocesses. The results are compared to recent ZEUS data.


title:
Nonanomalous R-symmetry in supersymmetric unified theories of quarks and
  leptons

abstract:
  A discrete R-symmetry often appears as an exact gauge symmetry in the low
energy effective theory of superstring theories. We search for such discrete
R-symmetries from a phenomenological point of view and find that Z_{9R} and
Z_{18R} are candidates of the nonanomalous R-symmetry in the case of the
minimal supersymmetric standard model. We also find Z_{4R} and Z_{20R} in the
case that quarks and leptons are embedded in the SU(5) GUT multiplets.
Interesting is that in the latter case all the solutions predict some extra
matter multiplets and we find that the simplest choice is to take a pair of
{\bf 5} and {\bf 5}^* of SU(5)_{GUT} whose mass is of order the SUSY breaking
scale \sim 1 TeV. We emphasize that the presence of such extra matters is
testable in future collider experiments.


title: Signals of R-parity Violating Supersymmetry at a Muon Storage Ring

abstract:
  Neutrino oscillation signals at muon storage rings (MSR) can be mimicked by
Supersymmetric (SUSY) interactions in an R-parity violating scenario. We have
investigated the $\tau$-appearance signals for both long-baseline and near-site
experiments, and concluded that the latter is of great use in distinguishing
between oscillation and SUSY effects. On the other hand, SUSY can cause a
manifold increase in the event rate for wrong-sign muons at a long-baseline
setting, thereby providing us with signatures of new physics.


title: Rho meson form-factors in the null-plane phenomenology

abstract:
  The constituent quark rho meson electromagnetic form-factors are calculated,
with covariant and null-plane approaches with the same model. The null-plane
formalism produces the breakdown of the rotational symmetry for the one-body
current operador, wich is investigated by comparing the numerical results in
both approaches. This allows to choose the appropriate null-plane prescriptio,
among the several ones, to evaluate the rho meson form-factors.


title:
Super-Kamiokande atmospheric neutrinos: Status of subdominant
  oscillations

abstract:
  In the context of the recent (79.5 kTy) Super-Kamiokande atmospheric neutrino
data, we concisely review the status of muonic-tauonic flavor oscillations and
of the subdominant electron or sterile neutrino mixing, in schemes with three
or four families and one dominant mass scale. In the three-family case, where
we include the full CHOOZ spectral data, we also show, through a specific
example, that ``maximal'' violations of the one-dominant mass scale
approximation are not ruled out yet.


title: Realistic Supersymmetric SU(6)

abstract:
  We present an example of SUSY SU(6) GUT, which predicts an excellent value
for $\al_s(M_Z)(\simeq 0.119)$, in comparison with the value
$\al_s^0(M_Z)\simeq 0.126$ of minimal SUSY SU(5). A crucial role is played by
the vectorlike multiplets from the matter sector, whose masses lie below the
GUT scale. For a realistic pattern of fermion masses, the adjoint scalar of
SU(6) has VEV along the $SU(4)\times SU(2)\times U(1)$ direction. This also
offers a natural resolution of the doublet-triplet (DT) splitting through the
pseudo Goldstone Boson mechanism.


title: Nonperturbative corrections to the quark self-energy

abstract:
  Nonperturbative self-energy of a bound quark is computed gauge-invariantly in
the framework of background perturbation theory. The resulting Delta m^2_q is
negative and is a universal function of string tension and current quark mass.
The shift of hadron mass squared, M^2, due to Delta m^2_q is negative, large
for light quarks, and solves the long-standing problem of Regge intercepts in
relativistic quark models.


title: The Kugo-Ojima Confinement Criterion from Dyson-Schwinger Equations

abstract:
  Prerequisites of confinement in the covariant and local description of QCD
are reviewed. In particular, the Kugo-Ojima confinement criterion, the
positivity violations of transverse gluon and quark states, and the conditions
necessary to avoid the decomposition property for colored clusters are
discussed. In Landau gauge QCD, the Kugo-Ojima confinement criterion follows
from the ghost Dyson-Schwinger equation if the corresponding Green's functions
can be expanded in an asymptotic series. Furthermore, the infrared behaviour of
the propagators in Landau gauge QCD as extracted from solutions to truncated
Dyson-Schwinger equations and lattice simulations is discussed in the light of
these issues.


title:
O(n) Spin Systems- Some General Properties: A Generalized
  Mermin-Wagner-Coleman Theorem, Ground States, Peierls Bounds, and Dynamics

abstract:
  Here we examine O(n) systems with arbitrary two spin interactions (of
unspecified range) within a general framework. We shall focus on
translationally invariant interactions. In the this case, we determine the
ground states of the $O(n \ge 2)$ systems. We further illustrate how one may
establish Peierls bounds for many Ising systems with long range interactions.
We study the effect of thermal fluctuations on the ground states and derive the
corresponding fluctuation integrals. The study of the thermal fluctuation
spectra will lead us to discover a very interesting odd-even $n$
(coupling-decoupling) effect. We will prove a generalized Mermin-Wagner-Coleman
(integral divergence) theorem for all translationally invariant interactions in
two dimensions with an analytic kernel in momentum space. We will show that
many three dimensional systems have smectic like thermodynamics. We will
examine the topology of the ground state manifolds for both translationally
invariant and spin glass systems. We conclude with a discussion of O(n) spin
dynamics in the general case.


title: Neutrino Mass Spectra, CP-Violation and Neutrinoless Double Beta-Decay

abstract:
  Assuming 3-neutrino mixing and massive Majorana neutrinos, we present some
implications of the neutrino oscillation solutions of the solar and atmospheric
neutrino problems and the results of the CHOOZ experiment for the predictions
of the neutrinoless double-beta decay rate. If the present or upcoming searches
of neutrinoless double-beta decay give a positive result, the Majorana nature
of massive neutrinos will be established. From the determination of the value
of the effective Majorana mass, it would be possible to obtain information on
the neutrino mass spectrum. With additional information on the absolute value
of neutrino masses, it might be possible to infer if CP-parity is violated in
the lepton sector.


title: Probabilities of rapidity gaps in high energy interactions

abstract:
  We show that high energy hadronic reactions which contain a rapidity gap and
a hard subprocess have a specific dependence on the kinematic variables, which
results in a characteristic behaviour of the survival probability of the gap.
We incorporate this mechanism in a two-channel eikonal model to make an
essentially parameter-free estimate of diffractive dijet production at the
Tevatron, given the diffractive structure functions measured at HERA. The
estimates are in surprising agreement with the measurements of the CDF
collaboration. We briefly discuss the application of the model to other hard
processes with rapidity gaps.


title: W Boson Production with Associated Jets at Large Rapidities

abstract:
  We analyse W boson production at hadron colliders in association with one or
two jets, both with the exact kinematics and in the high-energy limit. We argue
that the configurations that are kinematically favoured tend to have the W
boson forward in rapidity. Thus W boson production in association with jets
lends itself naturally to extensions to the high-energy limit, which we examine
both at leading order and by resumming higher-order corrections through the
BFKL theory.


title: Upsilon Decay to a Pair of Bottom Squarks

abstract:
  We calculate the rate for $\Upsilon$ decay into a pair of bottom squarks as a
function of the masses of the bottom squark and the gluino. Data from decays of
the $\Upsilon$ states could provide significant new bounds on the existence and
masses of these supersymmetric particles.


title: Excited Heavy Baryons and Their Symmetries III: Phenomenology

abstract:
  Phenomenological applications of an effective theory of low-lying excited
states of charm and bottom isoscalar baryons are discussed at leading and
next-to-leading order in the combined heavy quark and large $N_c$ expansion.
The combined expansion is formulated in terms of the counting parameter
$\lambda\sim 1/m_Q, 1/N_c$; the combined expansion is in powers of
$\lambda^{1/2}$. We work up to next-to-leading order. We obtain
model-independent predictions for the excitation energies, the semileptonic
form factors and electromagnetic decay rates. The spin-averaged mass of the
doublet of the first orbitally excited sate of $\Lambda_b$ is predicted to be
approximately $5920 MeV$. It is shown that in the combined limit at leading and
next-to-leading order there is only one independent form factor describing
$\Lambda_b \to \Lambda_c \ell \bar{\nu}$; similarly, $\Lambda_b \to
\Lambda_{c}^{*} \ell \bar{\nu}$ and $\Lambda_b \to \Lambda_{c1} \ell \bar{\nu}$
decays are described by a single independent form factor. These form factors
are calculated at leading and next-to-leading order in the combined expansion.
The electromagnetic decay rates of the first excited states of $\Lambda_c$ and
$\Lambda_b$ are determined at leading and next-to leading order. The ratio of
radiative decay rates $\Gamma(\Lambda_{c}^{*} \to \Lambda_c \gamma) /
\Gamma(\Lambda_{b1} \to \Lambda_b \gamma)$ is predicted to be approximately
0.2, greatly different from the heavy quark effective theory value of unity.


title:
Next to leading order predictions for pi_0 gamma and pi_0 pi_0
  production at the LHC

abstract:
  The precise knowledge of photon pair production rates at the LHC is crucial
to estimate the sensitivity to a Higgs boson in the intermediate mass range.
This background consists not only of prompt photons but also of fake photons
stemming from pion decay. We present next to leading order predictions for the
invariant mass distributions of pion photon and pion pairs.


title: High Density Quark Matter under Stress

abstract:
  We study the effect of SU(3) flavor breaking on high density quark matter. We
discuss, in particular, the effect a non-zero electron chemical potential and a
finite strange quark mass. We argue that these perturbations trigger pion or
kaon condensation. The critical chemical potential behaves as $\mu_e\sim\sqrt{m
m_s} \Delta/p_F$ and the critical strange quark mass as $m_s \sim m^{1/3}
\Delta^{2/3}$, where $m$ is the light quark mass, $\Delta$ is the gap, and
$p_F$ is the Fermi momentum. We note that parametrically, both the critical
$\mu_e$ and $m_s^2/(2p_F)$ are much smaller than the gap.


title: LEP-wide combination of the search for the standard model Higgs boson

abstract:
  A search for the standard model Higgs boson at LEP is reported. The results
obtained by combining all standard model Higgs boson search channels of the
experiments (at the end of run in the year 2000) are discussed.


title:
A (re)interpretation of the QCD phase transition and of strangeness as
  QGP signature

abstract:
  The temperature at the chemical freeze-out and at zero baryochemical
potential has been extracted in a global analysis of $e^+e^-$, $p+p$, $p+
\overline{p}$ and $A+A$ collisions at $\sqrt{s}$=2-1800 GeV per N+N pair. We
demonstrate that the temperature at $\mu_B$=0, rises with the initial energy
density $\epsilon_i$, and saturates above $\epsilon_i$ $\sim$ 1 GeV/fm$^3$.
This behaviour is interpreted as mapping out the QCD phase transition
universally in particle and nuclear collisions. The critical energy density is
therefore identified to be $\epsilon_{crit}$ $\sim$ 1 $\pm$ 0.3 GeV/fm$^3$. We
show that strange particles at $\mu_B$=0, are not significantly enhanced in A+A
collisions as compared to $p+ \overline{p}$. The so called 'strangeness
suppression factor' ($\lambda_s = \frac{(2 \overline{s})} {(\overline{u} +
\overline{d})}$) as a function of $\epsilon_i$ is following the temperature,
rising and saturating universally above $\epsilon_{crit}$. This leads to a
reinterpretation of strangeness enhancement as QGP signature. Within this
interpretation the experimental puzzles with respect to strangeness production
can be naturally explained: e.g. the recent measured maximum of $K^+/\pi^+$ in
Pb+Pb collisions at 40 A GeV, is explained as due to $\mu_B$. We discuss under
which conditions 'strangeness enhancement' and '$J/\Psi$ suppresion' both set
in at $\epsilon_{crit}$ $\sim$ 1 GeV/fm$^3$.


title:
Oscillations of Faster than Light Majorana Neutrinos: A Causal Field
  Theory

abstract:
  In this paper, we carry out the canonical quantization of the field theory of
an interacting tachyonic Majorana neutrino. We show how micro-causality is
preserved in the physical scattering matrix elements between the in and out
vacua.
  The phenomenology of this radical proposal is nevertheless compatible with
normal timelike oscillations.


title: B --> pi l nu Decay and |V_{ub}|

abstract:
  B --> pi l nu decay is studied in the effective theory of heavy quark with
infinite mass limit. The leading order heavy flavor-spin independent universal
wave functions which parametrize the relevant matrix elements are evaluated via
light cone sum rule method in the effective theory. The important quark mixing
matrix element |V_{ub}| is then extracted via B --> pi l nu decay mode.


title: Physics at the front-end of a neutrino factory: a quantitative appraisal

abstract:
  We present a quantitative appraisal of the physics potential for neutrino
experiments at the front-end of a muon storage ring. We estimate the forseeable
accuracy in the determination of several interesting observables, and explore
the consequences of these measurements. We discuss the extraction of individual
quark and antiquark densities from polarized and unpolarized deep-inelastic
scattering. In particular we study the implications for the undertanding of the
nucleon spin structure. We assess the determination of alpha_s from scaling
violation of structure functions, and from sum rules, and the determination of
sin^2(theta_W) from elastic nu-e and deep-inelastic nu-p scattering. We then
consider the production of charmed hadrons, and the measurement of their
absolute branching ratios. We study the polarization of Lambda baryons produced
in the current and target fragmentation regions. Finally, we discuss the
sensitivity to physics beyond the Standard Model.


title:
Nonperturbative hyperfine contribution to the $b_1$ and $h_1$ meson
  masses

abstract:
  Due to the nonperturbative contribution to the hyperfine splitting the mass
of the $n^1P_1$ state is strongly correlated with the center of gravity $M_{\rm
cog}(n^3P_J)$ of the $n^3P_J$ multiplet: $M(n^1P_1)$ is less than $M_{\rm
cog}(n^3P_J)$ by about 40 MeV (20 MeV) for the 1P (2P) state. For $b_1(1235)$
the agreement with experiment is reached only if $a_0(980)$ belongs to the
$1^3P_J$ multiplet. The predicted mass of $b_1(2^1P_1)$ is $\approx 1620$ MeV.
For the isoscalar meson a correlation between the mass of $h_1$(1170)
$(h_1(1380))$ and $M_{cog}(1^3P_J)$ composed from light (strange) quarks also
takes place.


title:
CP Violation, Sneutrino Oscillation and Neutrino Masses in R-parity
  Violating Supersymmetric Standard Model

abstract:
  In supersymmetric theories, sneutrino--anti-sneutrino mixing can occur with
the oscillation time $\sim 0.01$ ps corresponding the atmospheric neutrino mass
scale $\sim 0.05$ eV. We explore the possibility of observing sneutrino
oscillation phenomena and CP violation when R-parity violation explains the
observed neutrino masses and mixing. It is shown for some parameter region in
the bilinear model of R-parity violation that the tiny sneutrino mass splitting
and time-dependent CP violating asymmetries could be measured in the future
experiments if the tau sneutrino is the lightest supersymmetric particle.


title: Probing Quark Matter In Neutron Stars

abstract:
  The presence of quark matter in neutron star interiors may have distinctive
signatures in basic observables such as (i) masses and radii [1], (ii) surface
temperatures versus age [2], (iii) spin-down rates of milli-second pulsars [3],
and (iv) neutrino luminosities from future galactic core collapse supernovae
[4]. I highlight recent developments in some of these areas with a view towards
assessing how theory may be confirmed by $\nu-$signals from future galactic
supernovae in detectors like SuperK, SNO and others under consideration,
including UNO [5], and by multi-wavelength photon observations with new
generation satellites such as the HST, Chandra, and XMM.


title: New CP Violation in Neutrino Oscillations

abstract:
  Measurements of CP--violating observables in neutrino oscillation experiments
have been studied in the literature as a way to determine the CP--violating
phase in the mixing matrix for leptons. Here we show that such observables also
probe new neutrino interactions in the production or detection processes.
Genuine CP violation and fake CP violation due to matter effects are sensitive
to the imaginary and real parts of new couplings. The dependence of the CP
asymmetry on source--detector distance is different from the standard one and,
in particular, enhanced at short distances. We estimate that future neutrino
factories will be able to probe in this way new interactions that are up to
four orders of magnitude weaker than the weak interactions. We discuss the
possible implications for models of new physics.


title:
Two-Loop Matrix Element of the Current-Current Operator in the Decay B
  -> X_s gamma

abstract:
  We evaluate the important two-loop matrix element <s gamma| Q_2 | b> of the
operator (cbar gamma^mu P_L b) (sbar gamma_mu P_L b) contributing to the
inclusive radiative decay B -> X_s gamma. The calculation is performed in the
NDR scheme, by means of asymptotic expansions method. The result is given as a
series in z = m_c^2/m_b^2 up to O(z^6). We confirm the result of Greub, Hurth
and Wyler obtained by a different method up to 0(z^3). Higher-order terms are
found to be numerically insignificant.


title: Exclusive Decay Amplitudes from Light-Cone Sum Rules

abstract:
  We review recent developments in QCD sum rule applications to semileptonic
B->pi and D->pi transitions.


title: Signatures for Majorana neutrinos in $e^- \gamma$ collider

abstract:
  We study the possibilities to detect Majorana neutrinos in $e^- \gamma$
colliders for different center of mass energies.
  We study the $W^- W^- l_j^{+}(l_j^+\equiv e^+ ,\mu^+ ,\tau^+)$ final state
which are, due to leptonic number violation, a clear signature for intermediate
Majorana neutrino contribution. Such a signal (final lepton have the opposite
charge of the initial lepton) is not possible if the heavy neutrinos are Dirac
particles. In our calculation we use the helicity formalism to obtain analytic
expressions for the amplitude and we have considered that the intermediate
neutrinos can be either on shell or off shell. Finally we present our results
for the total cross-section and for the angular distribution of the final
lepton. We also include a discussion on the expected events number as a
function of the input parameters.


title: Four Neutrino Mass Spectra at the Neutrino Factory

abstract:
  We study the physical reach of a Neutrino Factory in the 2+2 and 3+1 Four
Neutrino mixing scenarios, with similar results for the sensitivity to the
mixing angles. Huge CP-violating effects can be observed in both schemes with a
near, O(10) Km, detector of O(10) Kton size in the $\nu_\mu \to \nu_\tau$
channel. A smaller detector of 1 Kton size can still observe very large effects
in this channel.


title: A supersymmetric solution to the bottom-quark cross section anomaly

abstract:
  In this talk, I describe a supersymmetric solution to the long-standing
discrepancy between the bottom-quark production cross section and predictions
of perturbative quantum chromodynamics. Pair production of light gluinos, of
mass 12-16 GeV, with two-body decays into bottom quarks and bottom squarks, of
mass 2-5.5 GeV, yields the correct normalizations and shapes of the measured
bottom-quark distributions. One prediction of this scenario is that like-sign B
mesons, B+B+ and B-B-, should be produced with a measurable rate at the next
run of the Fermilab Tevatron Collider.


title: Photon Self-Energy in a Color Superconductor

abstract:
  In a color superconductor the diquark condensates break spontaneously both
the color and ordinary electromagnetism, leaving a remanining rotated U(1)
symmetry unbroken. The gauge interactions associated to this rotated symmetry
may be considered as the in-medium electromagnetism. We compute the in-medium
photon self-energy in the presence of diquark condensates at high baryonic
density and weak coupling. This is done to one-loop order for the cases of two
and three quark flavors. For vanishing temperature, a detailed discussion is
given of the low momentum behavior of the photon polarization tensor. A simple
physical picture for the propagation of light in color superconducting media is
obtained. The main new effect is due to the diquark condensates, which lead to
a strong dielectric constant of the medium. The magnetic permeability remains
unchanged, because the primary condensates have vanishing spin and angular
momentum. In the two flavor case, an additional contribution arises due to
gapless quarks and electrons, which is responsible for Debye screening effects.
We also discuss the low energy effective theory for the three flavor case in
the presence of electromagnetic interactions.


title: Photoproduction of the isolated photon at HERA in NLO QCD

abstract:
  The NLO QCD calculation for the photoproduction of the isolated photon with a
large pT at the HERA ep collider is presented. The single resolved photon
contribution and the QCD corrections of order alpha_s to the Born term are
consistently included. The NNLO contributions, the box and the double resolved
photon subprocesses, are sizeable and are taken into account in addition. The
importance of the isolation cut, as well as the influence of other experimental
cuts on pT and final photon rapidity distributions are discussed in detail. The
investigation of the renormalization scale dependence is performed in order to
estimate the size of missing higher order QCD corrections. Results are compared
with experimental data and with the prediction of a different NLO calculation.


title:
Theory and phenomenology of generalized parton distributions: a brief
  overview

abstract:
  The generalized parton distributions are non-perturbative objects, which
encode information on long distance dynamics in a number of exclusive
processes. They are hybrids of conventional parton densities, distribution
amplitudes and hadron form factors. We give a brief review of theoretical
developments in understanding of their properties, higher order perturbative
effects, power corrections, and experimental observables where they are
accessible.


title: A new sum rule to determine Vub/Vcb

abstract:
  We present a new sum rule which does not contain any Landau-pole effect and
allows a determination of Vub/Vcb with a theoretical error of O(5%).


title: Discriminating between effective theories of U_{A}(1) symmetry breaking

abstract:
  We address the question if one can empirically distinguish between the two
proposed solutions to the ``$U_A (1)$ problem'': the 't Hooft, and the
Veneziano-Witten $U_{A}(1)$ symmetry breaking effective interactions. Two
hadronic observables are offered as discriminants: (1) The scalar ($0^{+}$)
meson spectrum; (2) Weinberg's second spectral sum rule. Their present
experimental status is discussed.


title:
Color superconductivity at finite density and temperature with flavor
  asymmetry

abstract:
  Color superconductivity of QCD at finite density, temperature and flavor
asymmetry is studied within an approximation which the interaction is modeled
upon four--fermion interactions. We calculate the thermodynamic potential in
the so-called NJL-type model and study the phase structure at finite density,
temperature and flavor asymmetry. We find that a mixed phase appears at
sufficiently large flavor asymmetry and low temperature. A tricritical point in
the $T$-$\mu_B$-$\mu_I$ plane is also found.


title: A New Formulation for HQET

abstract:
  We proposed a new formulation for heavy quark effective theory (HQET), whose
Lagrangian is hermitian and has a manifest reparameterization invariance. As an
application, we calculated the semileptonic and nonleptonic inclusive heavy
hadron decay rates up to second order mass corrections and found that there are
no kinetic energy correction terms.


title:
Analytic Derivation of the Quark Distribution Functions Near x=1 by
  Statistical Methods

abstract:
  In this paper, we made a statistical approach on the thermodynamic structure
of the nucleon and its quark distributions. We assume that the nucleon is a
thermodynamic system of quarks and gluons. After we derived the quark density
of states from the Dirac Equation, we calculated each quark's chemical
potential, associating it with the quark's spin distribution. By using the sum
rule of the longitudinal momentum, we obtain a function showing the relation
between the temperature, radius and mass of the nucleon. The nucleon's radius
is determined by the total energy minimal principle, and thus the temperature
is also known. Finally, we deduced the quark distribution functions near x=1,
and the results are in agreement with the experimental data.


title:
Spin-dependent twist-4 matrix elements from the instanton vacuum:
  Flavor-singlet and nonsinglet

abstract:
  We estimate the twist-4 spin-1 nucleon matrix element f_2 in an
instanton-based description of the QCD vacuum. In addition to the
flavor-nonsinglet we compute also the flavor-singlet matrix element, which
appears in next-to-leading order of the (1/N_c)-expansion. The corresponding
twist-3 spin-2 matrix elements d_2 are suppressed in the packing fraction of
the instanton medium, (\bar \rho)/(\bar R) << 1. We use our results to estimate
the leading (1/Q^2) power corrections to the first moment of the proton and
neutron spin structure functions G_1, as well as the intrinsic charm
contribution to the nucleon spin.


title:
Impact of Higher Order and Soft Gluon Corrections on the Extraction of
  Higher Twist Effects in DIS

abstract:
  The impact of recently calculated next-to-next-to-leading order QCD
corrections and soft gluon resummations on the extraction of higher twist
contributions to the deep-inelastic structure function F_2 is studied using the
BCDMS and SLAC data. It is demonstrated to which extent the need for higher
twist terms is diminishing due to these higher order effects in the kinematical
region, 0.35 \le x \le 0.85 and Q^2>1.2 GeV^2, investigated. In addition,
theoretical uncertainties in the extraction of higher twist contributions are
discussed, and comparisons to results obtained previously are made.