title: Visions: The Coming Revolutions in Particle Physics

abstract:
  Wonderful opportunities await particle physics over the next decade, with the
coming of the Large Hadron Collider to explore the 1-TeV scale (extending
efforts at LEP and the Tevatron to unravel the nature of electroweak symmetry
breaking) and many initiatives to develop our understanding of the problem of
identity and the dimensionality of spacetime.


title: Thermodynamics of chiral symmetry at low densities

abstract:
  The phase diagram of two-color QCD as a function of temperature and baryon
chemical potential is considered. Using a low-energy chiral Lagrangian based on
the symmetries of the microscopic theory, we determine, at the one-loop level,
the temperature dependence of the critical chemical potential for diquark
condensation and the temperature dependence of the diquark condensate and
baryon density. The prediction for the temperature dependence of the critical
chemical potential is consistent with the one obtained for a dilute Bose gas.
The associated phase transition is shown to be of second order for low
temperatures and first order at higher temperatures. The tricritical point at
which the second order phase transition ends is determined. The results are
carried over to QCD with quarks in the adjoint representation and to ordinary
QCD at a non-zero chemical potential for isospin.


title: Can a CPT Violating Ether Solve ALL Electron (Anti)Neutrino Puzzles?

abstract:
  Assuming that CPT is violated in the neutrino sector seems to be a viable
alternative to sterile neutrinos when it comes to reconciling the LSND anomaly
with the remainder of the neutrino data. There are different (distinguishable)
ways of incorporating CPT violation into the standard model, including
postulating m different from \bar{m}. Here, I investigate the possibility of
introducing CPT violation via Lorentz-invariance violating effective operators
(``Ether'' potentials) which modify neutrino oscillation patterns like ordinary
matter effects. I argue that, within a simplified two-flavor like oscillation
analysis, one cannot solve the solar neutrino puzzle and LSND anomaly while
still respecting constraints imposed by other neutrino experiments, and comment
on whether significant improvements should be expected from a three-flavor
analysis. If one turns the picture upside down, some of the most severe
constrains on such CPT violating terms can already be obtained from the current
neutrino data, while much more severe constraints can arise from future
neutrino oscillation experiments.


title: Scenery from the Top: Study of the Third Generation Squarks at CERN LHC

abstract:
  In the minimal supersymmetric standard model (MSSM) properties of the third
generation sfermions are important from the viewpoint of discriminating the
SUSY breaking models and in the determination of the Higgs boson mass. If
gluinos are copiously produced at CERN LHC, gluino decays into tb through stop
and sbottom can be studied using hadronic decays of the top quark. The
kinematical endpoint of the gluino decays can be evaluated using a W sideband
method to estimate combinatorial backgrounds. This implies that fundamental
parameters related to the third generation squarks can be reliably measured.
The top-quark polarization dependence in the decay process may also be
extracted by looking at the b jet distribution near the kinematical endpoint.


title: The Crystallography of Color Superconductivity

abstract:
  We develop the Ginzburg-Landau approach to comparing different possible
crystal structures for the crystalline color superconducting phase of QCD, the
QCD incarnation of the Larkin-Ovchinnikov-Fulde-Ferrell phase. In this phase,
quarks of different flavor with differing Fermi momenta form Cooper pairs with
nonzero total momentum, yielding a condensate that varies in space like a sum
of plane waves. We work at zero temperature, as is relevant for compact star
physics. The Ginzburg-Landau approach predicts a strong first-order phase
transition (as a function of the chemical potential difference between quarks)
and for this reason is not under quantitative control. Nevertheless, by
organizing the comparison between different possible arrangements of plane
waves (i.e. different crystal structures) it provides considerable qualitative
insight into what makes a crystal structure favorable. Together, the
qualitative insights and the quantitative, but not controlled, calculations
make a compelling case that the favored pairing pattern yields a condensate
which is a sum of eight plane waves forming a face-centered cubic structure.
They also predict that the phase is quite robust, with gaps comparable in
magnitude to the BCS gap that would form if the Fermi momenta were degenerate.
These predictions may be tested in ultracold gases made of fermionic atoms. In
a QCD context, our results lay the foundation for a calculation of vortex
pinning in a crystalline color superconductor, and thus for the analysis of
pulsar glitches that may originate within the core of a compact star.

categories: hep-ph astro-ph cond-mat.soft cond-mat.stat-mech cond-mat.supr-con nucl-th


title:
Gauge Coupling Unification and Phenomenology of Selected Orbifold 5D N=1
  SUSY Models

abstract:
  We study gauge coupling unification and various phenomenological issues, such
as baryon number conservation, the $\mu $ problem and neutrino anomalies,
within SUSY 5D orbifold models. The 5D MSSM on an $S^{(1)}/Z_2$ orbifold with
'minimal' field content does not lead to low scale unification, while some of
its extensions can give unification near the multi TeV scale. Within the
orbifold SU(5) GUT, low scale unification can not be realized due to full SU(5)
multiplets participating in the renormalization above the compactification
scale. As alternative examples, we construct 5D N=1 SUSY Pati-Salam $SU(4)_c\tm
SU(2)_L\tm SU(2)_R\equiv G_{422}$ and flipped $SU(5)\tm U(1)\equiv G_{51}$ GUTs
[both maximal subgroups of SO(10)] on an $S^{(1)}/Z_2\tm Z_2'$ orbifold. New
examples of low scale unifications within $G_{422}$ are presented. For $G_{51}$
the unification scale is shown to be necessarily close to $\sim 10^{16}$ GeV.
The possible influence of brane couplings on the gauge coupling unification is
also outlined. For the resolution of the various phenomenological problems
extensions with a discrete ${\cal Z}$ symmetry turn out to be very effective.


title: Exploring Flavor Structure of Supersymmetry Breaking at B factories

abstract:
  We investigate quark flavor signals in three different supersymmetric models,
the minimal supergravity, the SU(5) SUSY GUT with right handed neutrinos, and
the minimal supersymmetric standard model with U(2) flavor symmetry, in order
to study physics potential of the present and future $B$ factories. We evaluate
CP asymmetries in various B decay modes, $\Delta m_{B_s}$, $\Delta m_{B_d}$,
and $\epsilon_K$. The allowed regions of the CP asymmetry in $B\to J/\psi K_S$
and $\Delta m_{B_s}/\Delta m_{B_d}$ are different for the three models so that
precise determinations of these observables in near future experiments are
useful to distinguish the three models. We also investigate possible deviations
from the standard model predictions of CP asymmetries in other B decay modes.
In particular, a large deviation is possible for the U(2) model. The
consistency check of the unitarity triangle including $B\to
\pi\pi,\rho\pi,D^{(*)}K^{(*)},D^{(*)}\pi,D^{*}\rho$, and so on, at future high
luminosity $e^+e^-$ $B$ factories and hadronic $B$ experiments is therefore
important to distinguish flavor structures of different supersymmetric models.


title: Axial vector form factor of nucleons in a light-cone diquark model

abstract:
  The nucleon axial vector form factor is investigated in a light-cone quark
spectator diquark model, in which Melosh rotations are applied to both the
quark and vector diquark. It is found that this model gives a very good
description of available experimental data and the results have very little
dependence on the parameters of the model. The relation between the nucleon
axial constant and the anomalous magnetic moment of nucleons is also discussed.


title: Why We Are Here

abstract:
  Opening talk at Snowmass 2001: a summer study on the future of particle
physics.


title: Next Steps

abstract:
  Closing talk at Snowmass 2001: a summer study on the future of particle
physics.


title: Flavour Mixing, Gauge Invariance and Wave-function Renormalisation

abstract:
  We clarify some aspects of the LSZ formalism and wave function
renormalisation for unstable particles in the presence of electroweak
interactions when mixing and CP violation are considered. We also analyse the
renormalisation of the CKM mixing matrix which is closely related to wave
function renormalisation. We critically review earlier attempts to define a set
of "on-shell" wave function renormalisation constants. With the aid of an
extensive use of the Nielsen identities complemented by explicit calculations
we corroborate that the counter term for the CKM mixing matrix must be
explicitly gauge independent and demonstrate that the commonly used
prescription for the wave function renormalisation constants leads to gauge
parameter dependent amplitudes, even if the CKM counter term is gauge invariant
as required. We show that a proper LSZ-compliant prescription leads to gauge
independent amplitudes. The resulting wave function renormalisation constants
necessarily possess absorptive parts, but we verify that they comply with the
expected requirements concerning CP and CPT. The results obtained using this
prescription are different (even at the level of the modulus squared of the
amplitude) from the ones neglecting the absorptive parts in the case of top
decay. The difference is numerically relevant.


title: Analytical and numerical properties of Affleck-Dine condensate formation

abstract:
  We present analytical and numerical properties of the coherently rotating
Affleck-Dine condensate formed along MSSM flat directions with the radiative
corrections to the mass terms included. We analyse the pressure $p$ of the
condensate, which is known to be negative if the potential grows slower than
the field squared. We show that ellipticity of the orbit of the rotating field
also affects the pressure. For circularly orbiting field the $p=0$ while the
smallest negative value, corresponding to the most unstable configuration, is
obtained for a coherently oscillating field. The AD condensate is known to
fragment into non-topological solitons called Q-balls. We also study
equilibration of Q-ball distribution resulting from the fragmentation of the
condensate analytically. We find that equilibration is dependent on the
energy-to-charge ratio $x$ of the condensate. We find the allowed range of $x$
numerically and deduce that equilibration is likely to happen.


title:
Physics potential and experimental challenges of the LHC luminosity
  upgrade

abstract:
  We discuss the physics potential and the experimental challenges of an
upgraded LHC running at an instantaneous luminosity of 10**35 cm-2s-1.
  The detector R&D needed to operate ATLAS and CMS in a very high radiation
environment and the expected detector performance are discussed.
  A few examples of the increased physics potential are given, ranging from
precise measurements within the Standard Model (in particular in the Higgs
sector) to the discovery reach for several New Physics processes


title: Light meson radial Regge trajectories

abstract:
  A new physical mechanism is suggested to explain the universal depletion of
high meson excitations. It takes into account the appearance of holes inside
the string world sheet due to $q\bar{q}$ pair creation when the length of the
string exceeds the critical value $R_1 \simeq 1.4$ fm. It is argued that a
delicate balance between large $N_c$ loop suppression and a favorable gain in
the action, produced by holes, creates a new metastable (predecay) stage with a
renormalized string tension which now depends on the separation r. This results
in smaller values of the slope of the radial Regge trajectories, in good
agreement with the analysis of experimental data in [Ref.3]


title:
Radiative M1-decays of heavy-light mesons in the relativistic quark
  model

abstract:
  Radiative magnetic dipole decays of heavy-light vector mesons into
pseudoscalar mesons V -> P\gamma are considered within the relativistic quark
model. The light quark is treated completely relativistically, while for the
heavy quark the 1/m_Q expansion is used. It is found that relativistic effects
result in a significant reduction of decay rates. Comparison with previous
predictions and recent experimental data is presented.


title: Precise Ratios for Neutrino-Nucleon and Neutrino-Nucleus Interactions

abstract:
  It is shown that several ratios of neutral to charged current cross sections
are determined accurately, because the largest contribution is determined by
isospin symmetry and the smaller terms are estimated from data or theoretical
calculations. This way the theoretical uncertainty is very small. It is further
discussed that the ratios can be measured at various distances from the origin
of the neutrino beams, because an increase with distance will be indication for
neutrino oscillations and will allow a precise determination of the oscillation
parameters. Finally, coherent scattering is discussed as a useful reaction for
oscillations and as a means of searching for new light particles.


title:
Supernova neutrinos: difference of nu_mu - nu_tau fluxes and conversion
  effects

abstract:
  The formalism of flavor conversion of supernova neutrinos is generalized to
include possible differences in the fluxes of the muon and tau neutrinos
produced in the star. In this case the radiatively induced difference of the
nu_mu and nu_tau potentials in matter becomes important. The nu_mu and nu_tau
flux differences can manifest themselves in the effects of the Earth matter on
the observed nu_e (antinu_e) signal if: (i) the neutrino mass hierarchy is
normal (inverted); (ii) the solution of the solar neutrino problem is in the
LMA region; (iii) the mixing U_{e3} is relatively large: |U_{e3}|>10^{-3}. We
find that for differences in the nu_mu - nu_tau (antinu_mu - antinu_tau)
average energies and/or integrated luminosities < 20 %, the relative deviation
of the observed nu_e (antinu_e) energy spectrum at E > 50 MeV from that in the
case of the equal fluxes can reach 20 - 30 % (10 - 15 %) for neutrinos crossing
the Earth. It could be detected in future if large detectors sensitive to the
nu_e (antinu_e) energy spectrum become available. The study of this effect
would allow one to test the predictions of the nu_mu, nu_tau, antinu_mu,
antinu_tau fluxes from supernova models and therefore give an important insight
into the properties of matter at extreme conditions. It should be taken into
account in the reconstruction of the neutrino mass spectrum and mixing matrix
from the supernova neutrino observations. We show that even for unequal nu_mu
and nu_tau fluxes, effects of leptonic CP violation can not be studied in the
supernova neutrino experiments.


title:
Neutralino Exchange Corrections to the Higgs Boson Mixings with Explicit
  CP Violation

abstract:
  A calculus for the derivatives of the eigen values of the neutralino mass
matrix with respect to the CP violating background fields is developed and used
to compute the mixings among the CP even and the CP odd Higgs sectors arising
from the inclusion of the neutralino sector consisting of the neutralino, the Z
boson, and the neutral Higgs bosons ($\chi^0_i-Z-h^0-H^0$) exchange in the loop
contribution to the effective potential including the effects of large CP
violating phases. Along with the stop, sbottom, stau and chargino-W-charged
Higgs ($\chi^+-W-H^+$) contributions computed previously the present analysis
completes the one loop corrections to the Higgs boson mass matrix in the
presence of large phases. CP violation in the neutral Higgs sector is discussed
in the above framework with specific focus on the mixings of the CP even and
the CP odd sectors arising from the neutralino sector. It is shown that
numerically the effects of the neutralino exchange contribution on the mixings
of the CP even and the CP odd sectors are comparable to the effects of the stop
and of the chargino exchange contributions and thus the neutralino exchange
contribution must be included for a realistic analysis of mixings in the CP
even and the CP odd sectors. Phenomenological implications of these results are
discussed.


title: Higgs-Boson Production in Association with a Single Bottom Quark

abstract:
  Higgs bosons from an extended Higgs sector, such as a two-Higgs-doublet
model, can have greatly enhanced coupling to the bottom quark. Producing such a
Higgs boson in association with a single high-p_T bottom quark via g b -> h b
allows for the suppression of backgrounds. Previous studies have instead used g
g,qbar q -> bbar b h as the production mechanism, which is valid only if both b
quarks are at high p_T. We calculate g b -> h b at next-to-leading order in
QCD, and find that it is an order of magnitude larger than g g,qbar q -> bbar b
h at the Fermilab Tevatron and the CERN Large Hadron Collider. This production
mechanism improves the prospects for the discovery of a Higgs boson with
enhanced coupling to the b quark.


title: A Constraint on the x Dependence of the Light Antiquarks Ratio

abstract:
  We perform a careful study on the effect of the Pauli blocking to the light
antiquark structure of the proton sea. We develop the formal expressions for
the antiquark distributions, highlighting the role played by quark statistics
and the vacuum structure. Ratios involving the antiquarks are calculated. In
particular, it is found that $\Delta\bar{d}(x)/\Delta\bar{u}(x)$ should be
negative and x independent.


title: Parton model versus color dipole formulation of the Drell-Yan process

abstract:
  In the kinematical region where the center of mass energy is much larger than
all other scales, the Drell-Yan process can be formulated in the target rest
frame in terms of the same color dipole cross section as low Bjorken-x deep
inelastic scattering. Since the mechanisms for heavy dilepton production appear
very different in the dipole approach and in the conventional parton model, one
may wonder whether these two formulations really represent the same physics. We
perform a comparison of numerical calculations in the color dipole approach
with calculations in the next-to-leading order parton model. For proton-proton
scattering, the results are very similar at low x_2 from fixed target to RHIC
energies, confirming the close connection between these two very different
approaches. We also compare the transverse momentum distributions of Drell-Yan
dileptons predicted in both formulations. The range of applicability of the
dipole formulation and the impact of future Drell-Yan data from RHIC for
determining the color dipole cross section are discussed. A detailed derivation
of the dipole formulation of the Drell-Yan process is also included.


title: Nuclear effects in the Drell-Yan process

abstract:
  In the target rest frame and at high energies, Drell-Yan (DY) dilepton
production looks like bremsstrahlung of massive photons, rather than parton
annihilation. The projectile quark is decomposed into a series of Fock states.
Configurations with fixed transverse separations in impact parameter space are
interaction eigenstates for proton-proton (pp) scattering. The DY cross section
can then be expressed in terms of the same color dipole cross section as DIS.
We compare calculations in this dipole approach with E772 data and with
next-to-leading order parton model calculations. This approach is especially
suitable to describe nuclear effects, since it allows one to apply Glauber
multiple scattering theory. We go beyond the Glauber eikonal approximation by
taking into account transitions between states, which would be eigenstates for
a proton target. We calculate nuclear shadowing at large Feynman-x for DY in
proton-nucleus collisions and compare to E772 data. Nuclear effects on the
transverse momentum distribution are also investigated.


title: SO(10) a la Pati-Salam

abstract:
  We present rules for rewriting SO(10) tensor and spinor invariants in terms
of invariants of its ``Pati-Salam'' maximal subgroup (SU(4)$\times
\rm{SU(2)}_L\times \rm{SU(2)}_R)$ supplemented by the discrete symmetry called
D parity. Explicit decompositions of quadratic and cubic invariants relevant to
GUT model building are presented and the role of D parity in organizing the
terms explained. Our rules provide a complete and explicit method for obtaining
the "Clebsch-Gordon" Coefficients for $SO(10)\leftrightarrow G_{PS}$ in a
notation appropriate for field theory models. We illustrate the usefulness our
methods by calculating previously unavailable mass matrices and couplings of
the $SU(2)_L$ doublets and $SU(3)_c $ triplets in the minimal Susy SO(10) GUT
which are essential to specify the phenomenology of this model. We also present
the bare effective potential for Baryon number violation in this model and show
that it recives novel contributions from exchange of triplet Higgsinos
contained the in ``neutrino mass'' Higgs submultiplets
${\bf{\bar{\Sigma}}}_{126}(10,1,3)$. This further tightens the emerging
connection between neutrino mass and proton decay.


title: GUT Genealogies for Susy Seesaw Higgs

abstract:
  We discuss the embedding of R-Parity preserving Minimal Left Right
Supersymmetric models into Pati-Salam and SO(10) GUTs.


title: CP Violation in K-Meson Decays

abstract:
  This is a pedagogical review of some selected topics of CP and T violation in
the decays of K mesons. Diagonalization of the quark mass matrix and the
emergence of the complex phase in both the standard and the left--right
symmetric models is considered in great detail. Prominence is given to a
correct definition of the CP-violating quantities: $\epsilon, \epsilon'$ {\it
etc.} (with due regard for the Wu--Yang phase convention) and to formulation of
the time-reversal invariance criterion in the elementary particle physics. A
particular attention has been concentrated on theoretical evaluation of the
parameters $\epsilon$ and $\epsilon'$ and the CP- and T-violating asymmetries
in the decays $K \to \mu\nu\gamma$ and $K \to 3\pi$.


title: Probing physics beyond the standard model from lepton sector

abstract:
  In this review we discuss physics of the lepton sector, the anomalous dipole
moment of muon, the charged lepton-flavor violation, and the electric dipole
moments of charged leptons, from viewpoints of the minimal supersymmetric
standard model and the extensions.


title:
Exploring CP Violation through Correlations in B --> pi K, B_d -->
  pi^+pi^-, B_s --> K^+K^- Observable Space

abstract:
  We investigate allowed regions in observable space of B --> pi K, B_d -->
pi^+pi^- and B_s --> K^+K^- decays, characterizing these modes in the Standard
Model. After a discussion of a new kind of contour plots for the $B\to\pi K$
system, we focus on the mixing- induced and direct CP asymmetries of the decays
B_d --> pi^+pi^- and B_s--> K^+K^-. Using experimental information on the
CP-averaged B_d --> pi^{+/-}K^{+/-} and B_d --> pi^+pi^- branching ratios, the
relevant hadronic penguin parameters can be constrained,implying certain
allowed regions in observable space. In the case of B_d --> pi^+pi^-, an
interesting situation arises now in view of the recent B-factory measurements
of CP violation in this channel, allowing us to obtain new constraints on the
CKM angle gamma as a function of the B^0_d--\bar{B^0_d} mixing phase
phi_d=2beta, which is fixed through A_{CP}^{mix}(B_d --> J/psi K_S) up to a
twofold ambiguity. If we assume that A_{CP}^{mix}(B_d --> pi^+pi^-) is
positive, as indicated by recent Belle data, and that phi_d is in agreement
with the ``indirect'' fits of the unitarity triangle, also the corresponding
values for gamma around 60 degrees can be accommodated. On the other hand, for
the second solution of phi_d, we obtain a gap around gamma ~ 60 degrees. The
allowed region in the space of A_{CP}^{mix}(B_s --> K^+K^-) and
A_{CP}^{dir}(B_s --> K^+K^-) is very constrained in the Standard Model, thereby
providing a narrow target range for run II of the Tevatron and the experiments
of the LHC era.


title: Quantum Corrections to Newton's Law

abstract:
  We present a new approach to quantum gravity starting from Feynman's
formulation for the simplest example, that of a scalar field as the
representative matter. We show that we extend his treatment to a calculable
framework using resummation techniques already well-tested in other problems.
Phenomenological consequences for Newton's law are described.


title:
Stable quark stars beyond neutran stars : can they account for the
  missing matter ?

abstract:
  The structure of a spherically symmetric stable dark 'star' is discussed, at
zero temperature, containing 1) a core of quarks in the deconfined phase and
antileptons 2) a shell of hadrons in particular $n$, $p$, $\Lambda$ and
$\Sigma^-$ and leptons or antileptons and 3) a shell of hydrogen in the
superfluid phase. If the superfluid hydrogen phase goes over into the
electromagnetic plasma phase at densities well below one atom / $(10 fm)^{3}$,
as is usually assumed, the hydrogen shell is insignificant for the mass and the
radius of the 'star'. These quantities are then determined approximatively :
mass = 1.8 solar masses and radius = 9.2 km. On the contrary if densities of
the order of one atom / $(10 fm)^{3}$ do form a stable hydrogen superfluid
phase, we find a large range of possible masses from 1.8 to 375 solar masses.
The radii vary accordingly from 9 to 1200 km.


title: The Electroweak Theory

abstract:
  After a short essay on the current state of particle physics, I review the
antecedents of the modern picture of the weak and electromagnetic interactions
and then undertake a brief survey of the $SU(2)_{L}\otimes U(1)_{Y}$
electroweak theory. I review the features of electroweak phenomenology at tree
level and beyond, present an introduction to the Higgs boson and the 1-TeV
scale, and examine arguments for enlarging the electroweak theory. I conclude
with a brief look at low-scale gravity.


title: Family replicated calculation of baryogenesis

abstract:
  In our model with a Standard Model gauge group extended with a baryon number
minus lepton number charge for each family of quarks and leptons, we calculate
the baryon number relative to entropy produced in early Big Bang by the
Fukugita-Yanagida mechanism. With the parameters, i.e., the Higgs VEVs already
fitted in a very successful way to quark and lepton masses and mixing angles we
obtain the order of magnitude pure prediction Y_B=2.59{+17.0\atop-2.25}\times
10^{-11} which according to a theoretical estimate should mean in this case an
uncertainty of the order of a factor 7 up or down (to be compared to
Y_B=(1.7-8.1)\times 10^{-11}) using a relatively crude approximation for the
dilution factor, while using another estimate based on Buchm\"uller and
Pl\"umacher a factor 500 less, but this should rather be considered a lower
limit. With a realistic uncertainty due to wash-out of a factor 100 up or down
we even with the low estimate only deviate by 1.5\sigma.


title: A connection between gravity and the Higgs field

abstract:
  Several arguments suggest that an effective curved space-time structure (of
the type as in General Relativity) can actually find its dynamical origin in an
underlying condensed medium of spinless quanta. For this reason, we exploit the
recent idea of density fluctuations in a `Higgs condensate' with the conclusion
that such long-wavelength effects might represent the natural dynamical agent
of gravity.


title: Nucleon-Nucleon Scattering in the 1/N Expansion

abstract:
  The nucleon-nucleon 3S1-3D1 coupled-channel problem is solved analytically to
leading order in a joint expansion in the quark masses and in 1/N. An
approximate expression is derived for the 3S1 scattering length in the large-N
limit, and the large-N behavior of the deuteron is discussed.


title: Viable models with non-universal gaugino mediated supersymmetry breaking

abstract:
  Recently, extra dimensional SUSY GUT models have been proposed in which
compactification of the extra dimension(s) leads to a breakdown of the gauge
symmetry and/or supersymmetry. We examine a particular class of
higher-dimensional models exhibiting supersymmetry and SU(5) or SO(10) GUT
symmetry. SUSY breaking occurs on a hidden brane, and is communicated to the
visible brane via gaugino mediation. Non-universal gaugino masses are developed
at the compactification scale as a consequence of a restricted gauge symmetry
on the hidden brane. In this case, the compactification scale is at or slightly
below the GUT scale. We examine the parameter space of such models where
gaugino masses are related due to a Pati-Salam symmetry on the hidden brane. We
find limited but significant regions of model parameter space where a viable
spectra of SUSY matter is generated. Our results are extended to the more
general case of three independent gaugino masses; here we find that large
parameter space regions open up for large values of the U(1) gaugino mass M_1.
We also find the relic density of neutralinos for these models to be generally
below expectations from cosmological observations, thus leaving room for hidden
sector states to make up the bulk of cold dark matter. Finally, we evaluate the
branching fraction BF(b -> s gamma) and muon anomalous magnetic moment a_\mu.


title: Constraints on the SU(3) Electroweak Model

abstract:
  We consider a recent proposal by Dimopoulos and Kaplan to embed the
electroweak SU(2)_L X U(1)_Y into a larger group SU(3)_W X SU(2) X U(1) at a
scale above a TeV. This idea is motivated by the prediction for the weak mixing
angle sin^2 theta_W = 1/4, which naturally appears in these models so long as
the gauge couplings of the high energy SU(2) and U(1) groups are moderately
large. The extended gauge dynamics results in new effective operators that
contribute to four-fermion interactions and Z pole observables. We calculate
the corrections to these electroweak precision observables and carry out a
global fit of the new physics to the data. For SU(2) and U(1) gauge couplings
larger than 1, we find that the 95% C.L. lower bound on the matching (heavy
gauge boson mass) scale is 11 TeV. We comment on the fine-tuning of the high
energy gauge couplings needed to allow matching scales above our bounds. The
remnants of SU(3)_W breaking include multi-TeV SU(2)_L doublets with electric
charge (+-2,+-1). The lightest charged gauge boson is stable, leading to
cosmological difficulties.


title:
Classical sum rules and spin correlations in photoabsorption and
  photoproduction processes

abstract:
  In this paper we study the possibility of generalizing the classical
photoabsorption ($\gamma a \to b c$) sum rules, to processes $b c \to \gamma a$
and crossed helicity amplitudes. In the first case, using detailed balance, the
sum rule is written as $\int_{\nu_{th}}^\infty {\frac{{d\nu}}{\nu}} K\Delta
\sigma_{Born} (\nu)=0$ where $K$ is a kinematical constant which depends only
on the mass of the particles and the center of mass energy. For other crossed
helicity amplitudes, we show that there is a range of values of $s$ and $t$ for
which the differential cross section for the process $\gamma b \to a c$ or $a c
\to \gamma b$ in which the helicities of the photon and particle $a$ have
specific values, is equal to the differential cross section for the process in
which one of these two helicities is reversed (parallel-antiparallel spin
correlation).


title: Do solar neutrinos decay?

abstract:
  Despite the fact that the solar neutrino flux is now well-understood in the
context of matter-affected neutrino mixing, we find that it is not yet possible
to set a strong and model-independent bound on solar neutrino decays. If
neutrinos decay into truly invisible particles, the Earth-Sun baseline defines
a lifetime limit of $\tau/m \agt 10^{-4}$ s/eV. However, there are many
possibilities which must be excluded before such a bound can be established.
There is an obvious degeneracy between the neutrino lifetime and the mixing
parameters. More generally, one must also allow the possibility of active
daughter neutrinos and/or antineutrinos, which may partially conceal the
characteristic features of decay. Many of the most exotic possibilities that
presently complicate the extraction of a decay bound will be removed if the
KamLAND reactor antineutrino experiment confirms the large-mixing angle
solution to the solar neutrino problem and measures the mixing parameters
precisely. Better experimental and theoretical constraints on the $^8$B
neutrino flux will also play a key role, as will tighter bounds on absolute
neutrino masses. Though the lifetime limit set by the solar flux is weak, it is
still the strongest direct limit on non-radiative neutrino decay. Even so,
there is no guarantee (by about eight orders of magnitude) that neutrinos from
astrophysical sources such as a Galactic supernova or distant Active Galactic
Nuclei will not decay.


title: TeV String State Excitation via High Energy Cosmic Neutrinos

abstract:
  We construct the open-string scattering amplitudes for neutrino-gluon
collisions and evaluate the high energy neutrino-nucleon scattering cross
section via string state excitations in the TeV string-scale scenario. We find
that the neutrino-gluon scattering is the dominant contribution, 5-10 times
larger than neutrino-quark processes, though black hole production may be
larger than the string contribution at higher energies. We illustrate the
observability of the string signal at the Auger Observatory and the IceCube
neutrino telescope for a string scale about 1 TeV.


title: Next-to-leading order numerical calculations in Coulomb gauge

abstract:
  Calculations of observables in quantum chromodynamics can be performed using
a method in which all of the integrations, including integrations over virtual
loop momenta, are performed numerically. We use the flexibility inherent in
this method in order to perform next-to-leading order calculations for event
shape variables in electron-positron annihilation in Coulomb gauge. The use of
Coulomb gauge provides the potential to go beyond a purely order alpha_s^2
calculation by including, for instance, renormalon or parton showering effects.
We expect that the approximations needed to include such effects at all orders
in alpha_s will be simplest in a gauge in which unphysically polarized gluons
do not propagate over long distances.


title:
The Canonical Transformation and Duality in the 1+1 dimensional $\phi^4$
  and $\phi^6$ theory

abstract:
  We investigate the self-organizing nature of relativistic quantum field
theory in terms of canonical transformation and duality presenting simple but
explicit examples of $(\phi^4)_{1+1}$ and $(\phi^6)_{1+1}$ theories. Our
purpose is fulfilled by applying the oscillator representation (OR) method
which allows us to convert the original strong interaction theory into a weekly
interacting quasiparticle theory that is equivalent to the original theory. We
discuss advantages of the OR method and compare the results with what was
already obtained by the method of Gaussian effective potential (GEP) and the
Hartree approximation (HA). While we confirm that the GEP results are identical
to the Hartree results for the ground state energy, we found that the OR method
gives the quasiparticle mass different from the GEP and HA results. In our
examples, the self-organizing nature is revealed by the vacuum energy density
that gets lowered when the quasiparticles are formed. In the $(\phi^6)_{1+1}$
theory, we found two physically meaningful duality-related quasiparticle
solutions which have different symmetry properties under the transition of
quasiparticle field $\Phi \to -\Phi$. However, these two quasiparticle
solutions yield the identical effective potential in the strong coupling limit
of the original theory.


title: Small x Phenomenology: Summary and Status

abstract:
  The aim of this paper is to summarize the general status of our understanding
of small x physics. It is based on presentations and discussions at an informal
meeting on this topic held in Lund, Sweden, in March 2001. This document also
marks the founding of an informal collaboration between experimentalists and
theoreticians with a special interest in small x physics.
  This paper is dedicated to the memory of Bo Andersson, who died unexpectedly
from a heart attack on March 4th, 2002.


title: Inclusive Spectra and Quantum Stochastic Processes

abstract:
  We try to explain the apparently "thermal" shape of the inclusive transverse
momentum spectrum. We conjecture that prior to the collision, parton-parton
interactions generate a kind of a stochastic process driving the one-particle
spectrum within a hadron towards the thermal shape it would have in a classical
gas. We illustrate this idea, which might have a more general relevance, with a
simple, exactly solvable model.


title:
Discrete energy spectrum of Hawking radiation from Schwarzschild
  surfaces

abstract:
  We analyze the allowed energy levels of Hawking radiation from Schwarzschild
surfaces in space-times with large extra dimensions. From the requirement that
the wave functions associated with these particles be single-valued and obey
radial boundary conditions, we derive an upper bound of their discrete energy
spectrum as a function of the number of large extra dimensions and the mass of
the black hole. Furthermore, we investigate the spacing of the energy levels.


title:
Possibility of the LBL experiment with the high intensity proton
  accelerator

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


title:
The Forward-Backward Asymmetry of B to (pi,K) l^+ l^-: Supersymmetry at
  Work

abstract:
  We analyze the forward-backward asymmetry of the decays B to (pi,K) l^+ l^-
with l = mu or tau in the framework of the constrained minimal supersymmetric
standard model. We find that, the asymmetry is enhanced at large tan beta and
depends strongly on the sign of the mu parameter. For mu > 0, the asymmetry is
typically large and observable whereas for mu < 0, it changes the sign and is
suppressed by an order of magnitude. Including cosmological constraints we find
that the asymmetry has a maximal value of about 30 %, produced when Higgs- and
gauge- induced flavor violations are of comparable size, at a value of tan beta
simeq 35. The present constraints from the B-factories are too weak to
constrain parameter space, and the regions excluded by them are already
disfavoured by at least one of B to X_s gamma, g-2, and/or cosmology. The size
of the asymmetry is mainly determined by the flavor of the final state lepton
rather than the flavor of the pseudoscalar.


title: QCD vacuum structure in strong magnetic fields

abstract:
  We study the response of the QCD vacuum to strong magnetic fields, using a
potential model for the quark-antiquark interaction. We find that production of
spin-polarized u-ubar pairs is energetically favorable for fields B > B_crit
\sim 10 GeV^2. We contrast the resulting u-ubar condensate with the quark
condensate which is present at zero magnetic field, and we estimate the
corresponding magnetization as a function of B.


title: Realistic extremely flat scalar potential in 3-3-1 models

abstract:
  We show that in 3-3-1 models it is possible to implement an extremely flat
scalar potential, i.e., a zero contribution to the cosmological constant, and
still having realistic values for the masses of the scalar Higgs fields.
Besides, when loop corrections are considered they impose constraints over
heavy particles masses (exotic quarks and extra vector bosons) which are
present in the model. A crucial ingredient in 3-3-1 models is the existence of
trilinear terms in the scalar potential. We also consider the two-Higgs
doublets extension of the standard model with and without supersymmetry.


title: Purely Four-dimensional Viable Anomaly Mediation

abstract:
  Anomaly mediation of supersymmetry breaking solves the supersymmetric flavor
problem thanks to its ultraviolet-insensitivity. However, it suffers from two
problems: sleptons have negative masses-squared, and there are likely bulk
moduli that spoil the framework. Here, we present the first fully
ultraviolet-insensitive model of anomaly mediation with positive slepton
masses-squared in a purely four-dimensional framework. Our model is based on
the additional D-term contributions to the sparticle masses, and the conformal
sequestering mechanism.


title: Implementation of supersymmetric processes in the HERWIG event generator

abstract:
  We describe the implementation of supersymmetric processes in the HERWIG
Monte Carlo event generator. We define relevant parameter and mixing
conventions and list the hard scattering matrix elements. Our implementation is
based on the Minimum Supersymmetric Standard Model, with the option of R-parity
violation. The sparticle spectrum is completely general. Both hadron-hadron and
lepton-lepton collisions are covered. This article supplements a separate
publication in which the general features of HERWIG 6.2 are described, and
updates the treatment of supersymmetry to version 6.4.


title: Superfluid phases of quark matter. III. Supercurrents and vortices

abstract:
  We study, within Ginzburg-Landau theory, the responses of three-flavor
superfluid quark-gluon plasmas to external magnetic fields and rotation, in
both the color-flavor locked and isoscalar color-antitriplet diquark phases
near the critical temperature. Fields are incorporated in the gradient energy
arising from long wavelength distortions of the condensate, via covariant
derivatives to satisfy local gauge symmetries associated with color and
electric charge. Magnetic vortex formation, in response to external magnetic
fields, is possible only in the isoscalar phase; in the color-flavor locked
phase, external magnetic fields are incompletely screened by the Meissner
effect. On the other hand, rotation of the superfluid produces vortices in the
color-flavor locked phase; in the isoscalar phase, it produces a London
gluon-photon mixed field. We estimate the coherence and Meissner lengths and
critical magnetic fields for the two phases.


title: Approximate NNLO Threshold Resummation in Heavy Flavour Decays

abstract:
  We present an approximate NNLO evaluation of the QCD form factor resumming
large logarithmic perturbative contributions in semi-inclusive heavy flavour
decays.


title: Hypermagnetic Field Effects in the Thermal Bath of Chiral Fermions

abstract:
  The dispersion relations for leptons in the symmetric phase of the
electroweak model in the presence of a constant hypermagnetic field are
investigated. The one-loop fermion self-energies are calculated in the lowest
Landau level approximation and used to show that the hypermagnetic field
forbids the generation of the ''effective mass'' found as a pole of the
fermions' propagators at high temperature and zero fields. In the considered
approximation leptons behave as massless particles propagating only along the
direction of the external field. The reported results can be of interest for
the cosmological implications of primordial hypermagnetic fields.


title: Parton Distribution Functions suitable for Monte-Carlo event generators

abstract:
  In the usual factorization theorems, which give predictions only for
inclusive cross sections, there is considerable freedom in the choice of the
scheme to define the parton distribution functions. These theorems do not
directly apply to Monte-Carlo event generators, and more general factorization
theorems which give predictions for fully exclusive cross sections are needed.
It has been shown that appropriate parton distribution functions are uniquely
defined by the showering algorithm. In this paper, we present results of
calculations of the Monte-Carlo parton distribution functions in terms of the
commonly used MSbar parton distribution functions. At small x the differences
are large, which demonstrates the importance of using the correct parton
distribution functions in an event generator rather than MSbar parton
distribution functions. We present some simple approximations that enable an
understanding of the sizes of the results to be obtained.


title: Pinch Technique and the Batalin-Vilkovisky formalism

abstract:
  In this paper we take the first step towards a non-diagrammatic formulation
of the Pinch Technique. In particular we proceed into a systematic
identification of the parts of the one-loop and two-loop Feynman diagrams that
are exchanged during the pinching process in terms of unphysical ghost Green's
functions; the latter appear in the standard Slavnov-Taylor identity satisfied
by the tree-level and one-loop three-gluon vertex. This identification allows
for the consistent generalization of the intrinsic pinch technique to two
loops, through the collective treatment of entire sets of diagrams, instead of
the laborious algebraic manipulation of individual graphs, and sets up the
stage for the generalization of the method to all orders. We show that the task
of comparing the effective Green's functions obtained by the Pinch Technique
with those computed in the background field method Feynman gauge is
significantly facilitated when employing the powerful quantization framework of
Batalin and Vilkovisky. This formalism allows for the derivation of a set of
useful non-linear identities, which express the Background Field Method Green's
functions in terms of the conventional (quantum) ones and auxiliary Green's
functions involving the background source and the gluonic anti-field; these
latter Green's functions are subsequently related by means of a Schwinger-Dyson
type of equation to the ghost Green's functions appearing in the aforementioned
Slavnov-Taylor identity.


title: The inclusive b -> s \gamma decay in the noncommutative standard model

abstract:
  We study the new structures appearing due to noncommutative effects in the
inclusive decay b -> s \gamma^*, in the standard model. We present the
corresponding coefficients which carries the space-space and space-time
noncommutativity.


title: Left-right asymmetries, the weak mixing angle, and new physics

abstract:
  The goal of this article is to outline the advantages of the measurement of
left-right asymmetries in lepton-lepton ($l^{-}l^{-}\to l^{-}l^{-}$) scattering
for performing precision measurements of $\sin^2 \theta_W$ and the discovery of
``new physics''.


title: Hadro-Chemistry and Evolution of (Anti-) Baryon Densities at RHIC

abstract:
  The consequences of hadro-chemical freezeout for the subsequent hadron gas
evolution in central heavy-ion collisions at RHIC and LHC energies are
discussed with special emphasis on effects due to antibaryons. Contrary to
naive expectations, their individual conservation, as implied by experimental
data, has significant impact on the chemical off-equilibrium composition of
hadronic matter at collider energies. This may reflect on a variety of
observables including source sizes and dilepton spectra.


title: Thermal conductivity of dense quark matter and cooling of stars

abstract:
  The thermal conductivity of the color-flavor locked phase of dense quark
matter is calculated. The dominant contribution to the conductivity comes from
photons and Nambu-Goldstone bosons associated with breaking of baryon number
which are trapped in the quark core. Because of their very large mean free path
the conductivity is also very large. The cooling of the quark core arises
mostly from the heat flux across the surface of direct contact with the nuclear
matter. As the thermal conductivity of the neighboring layer is also high, the
whole interior of the star should be nearly isothermal. Our results imply that
the cooling time of compact stars with color-flavor locked quark cores is
similar to that of ordinary neutron stars.


title: Lepton-Flavour Violation in SUSY with and without R-parity

abstract:
  We study whether the individual violation of the lepton numbers L_{e,mu,tau}
in the charged sector can lead to measurable rates for BR(mu->e gamma) and
BR(tau->mu gamma). We consider three different scenarios, the fist one
corresponds to the Minimal Supersymmetric Standard Model with non-universal
soft terms. In the other two cases the violation of flavor in the leptonic
charged sector is associated to the neutrino problem in models with a see-saw
mechanism and with R-parity violation respectively.


title:
Precise calculation of parity nonconservation in cesium and test of the
  standard model

abstract:
  We have calculated the 6s-7s parity nonconserving (PNC) E1 transition
amplitude, E_{PNC}, in cesium. We have used an improved all-order technique in
the calculation of the correlations and have included all significant
contributions to E_{PNC}. Our final value E_{PNC} = 0.904 (1 +/- 0.5 %) \times
10^{-11}iea_{B}(-Q_{W}/N) has half the uncertainty claimed in old calculations
used for the interpretation of Cs PNC experiments. The resulting nuclear weak
charge Q_{W} for Cs deviates by about 2 standard deviations from the value
predicted by the standard model.


title: Neutrino Indirect Detection of Neutralino Dark Matter in the CMSSM

abstract:
  We study potential signals of neutralino dark matter indirect detection by
neutrino telescopes in a wide range of CMSSM parameters. We also compare with
direct detection potential signals taking into account in both cases present
and future experiment sensitivities. Only models with neutralino annihilation
into gauge bosons can satisfy cosmological constraints and current neutrino
indirect detection sensitivities. For both direct and indirect detection, only
next generation experiments will be able to really test this kind of models.


title: Supersymmetry and a rationale for small CP violating phases

abstract:
  We analyse the CP problem in the context of a supersymmetric extension of the
standard model with universal strength of Yukawa couplings. A salient feature
of these models is that the CP phases are constrained to be very small by the
hierarchy of the quark masses, and the pattern of CKM mixing angles. This leads
to a small amount of CP violation from the usual KM mechanism and a significant
contribution from supersymmetry is required. Due to the large generation mixing
in some of the supersymmetric interactions, the electric dipole moments impose
severe constraints on the parameter space, forcing the trilinear couplings to
be factorizable in matrix form. We find that the LL mass insertions give the
dominant gluino contribution to saturate epsilon_K. The chargino contributions
to epsilon'/epsilon are significant and can accommodate the experimental
results. In this framework, the standard model gives a negligible contribution
to the CP asymmetry in B-meson decay, a_{J/\psi K_s}. However, due to
supersymmetric contributions to B_d-\bar{B}_d mixing, the recent large value of
a_{J/\psi K_s} can be accommodated.


title: Leptogenesis with Majorana neutrinos

abstract:
  I review the origin of the lepton asymmetry which is converted to a baryon
excess at the electroweak scale. This scenario becomes more attractive if we
can relate it to other physical phenomena. For this reason I elaborate on the
conditions of the early universe which lead to a sizable lepton asymmetry. Then
I describe methods and models which relate the low energy parameters of
neutrinos to the high energy (cosmological) CP-violation and to neutrinoless
double beta-decay.


title: Neutrino Interactions at Low and Medium Energies

abstract:
  We discuss the calculations for several neutrino induced reactions from low
energies to the GeV region. Special attention is paid to nuclear corrections
when the targets are medium or heavy nuclei. Finally, we present several ratios
of neutral to charged current reactions whose values on isoscalar targets can
be estimated accurately. The ratios are useful for investigating neutrino
oscillations in Long Baseline experiments.


title:
Remarks on the f_0(400-1200) scalar meson as the dynamically generated
  chiral partner of the pion

abstract:
  The quark-level linear sigma model is revisited, in particular concerning the
identification of the f_0(400-1200) (or \sigma(600)) scalar meson as the chiral
partner of the pion. We demonstrate the predictive power of the linear sigma
model through the pi-pi and pi-N s-wave scattering lengths, as well as several
electromagnetic, weak, and strong decays of pseudoscalar and vector mesons. The
ease with which the data for these observables are reproduced in the linear
sigma model lends credit to the necessity to include the sigma as a fundamental
q\bar{q} degree of freedom, to be contrasted with approaches like chiral
perturbation theory or the confining NJL model of Shakin and Wang.


title: A new model-independent way of extracting |V_ub/V_cb|

abstract:
  The ratio between the photon spectrum in B -> X_s gamma and the differential
semileptonic rate wrt the hadronic variable M_X/E_X is a short-distance
quantity calculable in perturbation theory and independent of the Fermi motion
of the b quark in the B meson. We present a NLO analysis of this ratio and show
how it can be used to determine |V_ub/V_cb| independently of any model for the
shape function. We also discuss how this relation can be used to test the
validity of the shape-function theory on the data.


title: Neutrino Masses in Theories with Dynamical Electroweak Symmetry Breaking

abstract:
  We address the problem of accounting for light neutrino masses in theories
with dynamical electroweak symmetry breaking. We discuss this in the context of
a class of (extended) technicolor (ETC) models and analyze the full set of
Dirac and Majorana masses that arise in such theories. As a possible solution,
we propose a combination of suppressed Dirac masses and a seesaw involving
dynamically generated $|\Delta L|=2$ condensates of standard-model singlet,
ETC-nonsinglet fermions. We show how this can be realized in an explicit ETC
model. An important feature of this proposal is that, because of the
suppression of Dirac neutrino mass terms, a seesaw yielding realistic neutrino
masses does not require superheavy Majorana masses; indeed, these Majorana
masses are typically much smaller than the largest ETC scale.


title: Fine Structure Constant Variation from a Late Phase Transition

abstract:
  Recent experimental data indicates that the fine structure constant alpha may
be varying on cosmological time scales. We consider the possibility that such a
variation could be induced by a second order phase transition which occurs at
late times (z ~ 1 - 3) and involves a change in the vacuum expectation value
(vev) of a scalar with milli-eV mass. Such light scalars are natural in
supersymmetric theories with low SUSY breaking scale. If the vev of this scalar
contributes to masses of electrically charged fields, the low-energy value of
alpha changes during the phase transition. The observational predictions of
this scenario include isotope-dependent deviations from Newtonian gravity at
sub-millimeter distances, and (if the phase transition is a sharp event on
cosmological time scales) the presence of a well-defined step-like feature in
the alpha(z) plot. The relation between the fractional changes in alpha and the
QCD confinement scale is highly model dependent, and even in grand unified
theories the change in alpha does not need to be accompanied by a large shift
in nucleon masses.


title:
Phenomenological Study of Solar-Neutrino Induced Double Beta Decay of
  Mo100

abstract:
  The detection of solar-neutrinos of different origin via induced beta beta
process of Mo100 is investigated. The particular counting rates and energy
distributions of emitted electrons are presented. A discussion in respect to
solar-neutrino detector consisting of 10 tones of Mo100 is included. Both the
cases of the standard solar model and neutrino oscillation scenarios are
analyzed. Moreover, new beta^- beta^+ and beta^-/EC channels of the double-beta
process are introduced and possibilities of their experimental observation are
addressed.


title:
Particle-Antiparticle Metamorphosis of Massive Majorana Neutrinos and
  Gauginos

abstract:
  Recent results on neutrinoless double beta decay, as reported by
Klapdor-Kleingrothaus et al., take us for the first time into the realm of
Majorana spacetime structure. However, this structure has either been treated
as an afterthought to the Dirac construct; or, when it has been attended to in
its own right, its physical and mathematical content was never fully unearthed.
In this Letter,we undertake to remedy the existing situation. We present a
detailed formalism required for the description of the non-trivial spacetime
structure underlying the "nu-nubar" metamorphosis - where "nu" generically
represents a massive Majorana neutrino, or a massive gaugino.


title: Enhanced thermal production of hard dileptons by $3\to 2$ processes

abstract:
  In the framework of the Hard Thermal Loop effective theory, we calculate the
two-loop contributions to hard lepton pair production in a quark-gluon plasma.
We show that the result is free of any infrared and collinear singularity. We
also recover the known fact that perturbation theory leads to integrable
singularities at the location of the threshold for $q\bar{q}\to\gamma^*$. It
appears that the process calculated here significantly enhances the rate of low
mass hard dileptons.


title:
A simple sum rule for the thermal gluon spectral function and
  applications

abstract:
  In this paper, we derive a simple sum rule satisfied by the gluon spectral
function at finite temperature. This sum rule is useful in order to calculate
exactly some integrals that appear frequently in the photon or dilepton
production rate by a quark gluon plasma. Using this sum rule, we rederive
simply some known results and obtain some new results that would be extremely
difficult to justify otherwise. In particular, we derive an exact expression
for the collision integral that appears in the calculation of the
Landau-Pomeranchuk-Migdal effect.


title: Nonresonant Contributions in B->rho pi Decay

abstract:
  We consider nonresonant contributions in the Dalitz plot analysis of B->rho
pi->pi^+ pi^- pi^0 decay and their potential impact on the extraction of the
CKM parameter alpha. In particular, we examine the role of the heavy mesons B^*
and B_0, via the process B->pi (B^*, B_0)->pi^+ pi^- pi^0, and their
interference with resonant contributions in the rho-mass region. We discuss the
inherent uncertainties and suggest that the effects may be substantially
smaller than previously indicated.


title:
A Monte Carlo Study of the Levy Stability and Multifractal Spectrum in
  e+e- collisions

abstract:
  The Levy stability analysis is carried out for e+e- collisions at Z^0 mass
using Monte Carlo method. The Levy index \mu is found to be \mu=1.701 +- 0.043.
The self-similar generalized dimensions D(q) and multi-fractal spectrum
f(\alpha) are presented. The Renyi dimension D(q) decreases with increasing q.
The self-similar multi-fractal spectrum is a convex curve with a maximum at q =
0, \alpha = 1.169 +- 0.011. The right-side part of the spectrum, corresponding
to negative values of q is obtained through analytical continuation.


title: $U_A(1)$ Symmetry Breaking and the Scalar Sector of QCD

abstract:
  It is shown that most of the unusual properties of the lowest lying scalar
(and pseudoscalar) mesons can be understood, at the qualitative and
quantitative level, on the basis of the breakdown of the $U_A(1)$ symmetry
coupled to the vacuum expectation values of scalars by the spontaneous breaking
of chiral symmetry.


title: Estimating higher order perturbative coefficients using Borel transform

abstract:
  A new method of estimating higher order perturbative coefficients is
discussed. It exploits the rapid, asymptotic growth of perturbative
coefficients and the information on the singularities in the complex Borel
plane. A comparison with other methods is made in several Quantum
Chromodynamics (QCD) expansions.


title:
Pseudoscalar pole terms contributions to hadronic light-by-light
  corrections to the muonium hyperfine splitting

abstract:
  The contribution of pseudoscalar pole diagrams to the hadronic light-by-light
corrections of order alpha^3 E_F to the ground state hyperfine splitting in
hydrogenic atom is calculated in the pseudoscalar pole terms approximation. The
vector dominance model for the form factor of the transition of a pseudoscalar
meson into two photons is used. With the account of new experimental data on
the cross sections sigma (e^+e^-\to \rho, \omega \to \pi^0(\eta)\gamma) in the
SND and CMD-2 experiments some other hadronic corrections to the muonium
hyperfine splitting are calculated.


title: The neutralino projector formalism for complex SUSY parameters

abstract:
  We present a new formalism describing the neutralino physics in the context
of the minimal supersymmetric model (MSSM), where CP violation induced by
complex $M_1$ and $\mu$ parameters is allowed. The formalism is based on the
construction of neutralino projectors, and can be directly generalized to
non-minimal SUSY models involving any number of neutralinos. It extends a
previous work applied to the real SUSY parameter case. In MSSM, the method
allows to describe all physical observables related to a specific neutralino,
in terms of its
  CP eigenphase and three complex numbers called its "reduced projector
elements".
  As the experimental knowledge on the neutralino-chargino sectors will be
being accumulated, the problem of extracting the various SUSY parameters will
arise. Motivated by this, we consider various scenarios concerning the
quantities that could be first measured. Analytical disentangled expressions
determining the related SUSY parameters from them, are then derived, which also
emphasize the efficiency of the formalism.


title:
Lepton flavor violating $Z\to l_il_j$ in flavor-universal
  topcolor-assisted technicolor

abstract:
  In the context of flavor-universal topcolor-assisted technicolor (TC2)
models, we calculate the lepton flavor violating (LFV) $Z\to l_il_j$ decays. We
find that the extra U(1) gauge boson $Z^{\prime}$ can give significant
contributions to these LFV processes. With reasonable values of the parameters,
the branching ratios of the processes $Z\to \tau\mu$ and $Z\to \tau e$ can
approach the experimental upper limits. The indirect bound on the process $Z\to
\mu e$ can give a severe constraint on the flavor-universal TC2 models.


title:
On the Influence of Einstein-Podolsky-Rosen Effect on the Domain Wall
  Formation during the Cosmological Phase Transitions

abstract:
  Search for the mechanisms suppressing formation of Higgs field defects (e.g.
domain walls) during the cosmological phase transitions is one of key problems
in explanation of the observed large-scale uniformity of the space-time. One of
the possible solutions can be based on accounting for Einstein-Podolsky-Rosen
(EPR) correlations. Namely, if a coherent quantum state of the Higgs field was
formed in the course of its previous evolution, then reduction to the state
with broken symmetry during the phase transition should be correlated even at
the scales exceeding the local cosmological horizons. Detailed consideration of
the simplest one-dimensional cosmological model with Z2 Higgs field
demonstrates that, at certain parameters of the Lagrangian, EPR-correlations
really result in a substantial suppression of spontaneous formation of the
domain walls.


title: Cosmological Effects of Radion Oscillations

abstract:
  We show that the redshift of pressureless matter density due to the expansion
of the universe generically induces small oscillations in the stabilized radius
of extra dimensions (the radion field). The frequency of these oscillations is
proportional to the mass of the radion and can have interesting cosmological
consequences. For very low radion masses $m_b$ ($m_b\sim10-100
H_0\simeq10^{-32} eV$) these low frequency oscillations lead to oscillations in
the expansion rate of the universe. The occurrence of acceleration periods
could naturally lead to a resolution of the coincidence problem, without need
of dark energy. Even though this scenario for low radion mass is consistent
with several observational tests it has difficulty to meet fifth force
constraints. If viewed as an effective Brans-Dicke theory it predicts
$\omega=-1+\frac{1}{D}$ ($D$ is the number of extra dimensions), while
experiments on scales larger than $1mm$ imply $\omega>2500$. By deriving the
generalized Newtonian potential corresponding to a massive toroidally compact
radion we demonstrate that Newtonian gravity is modified only on scales smaller
than $m_b^{-1}$. Thus, these constraints do not apply for $m_b>10^{-3} eV$
(high frequency oscillations) corresponding to scales less than the current
experiments ($0.3mm$). Even though these high frequency oscillations can not
resolve the coincidence problem they provide a natural mechanism for dark
matter generation. This type of dark matter has many similarities with the
axion.


title:
Recent experimental data and the size of the quark in the Constituent
  Quark Model

abstract:
  We use the Constituent Quark Model (CQM) to describe CDF data on double
parton cross section and HERA data on the $ J / \Psi$ ratio cross section of
elastic and inelastic diffractive productions. Our estimate shows that the
radius of the constituent quark turns out to be rather small, $R^2_{quark}
\approx 0.1 Gev^{-2}$, in accordance with the assumption on which CQM is based.


title: Calculation of some properties of the vacuum

abstract:
  In this article, we calculate the dressed quark propagator with the flat
bottom potential in the framework of the rain-bow Schwinger-Dyson equation,
which is determined by mean field approximation of the global colour model
lagrangian. The dressed quark propagator exhibits a dynamical symmetry breaking
phenomenon and gives a constituent quark mass about 392 MeV, which is close to
the value of commonly used constituent quark mass in the chiral quark model.
Then based on the dressed quark propagator, we calculate some properties of the
vacuum, such as quark condensate, mixed quark condensate $g_{s}<
0|\bar{q}G_{\mu\nu}\sigma^{\mu\nu}q|0>$, four quark condensate $<0|\bar{q}
\Gamma q\bar{q} \Gamma q |0>$, tensor, $\pi$ vacuum susceptibilities. The
numerical results are compatible with the values of other theoretical
approaches.


title: Dynamical symmetry breaking, confinement with flat-bottom potential

abstract:
  In this article, we calculate the dressed quark propagator with the flat
bottom potential in the framework of the rain-bow Schwinger-Dyson equation.
Then based on the nonperturbative dressed quark propagator, we calculate the
$\pi$ decay constant and the quark condensate. The $\pi$ decay constant is an
important parameter in describing the interplay between dynamical symmetry
breaking and confinement, while the quark condensate is an order parameter for
dynamical chiral symmetry breaking. To implement confinement, we prove that the
dressed quark propagator has no poles on the real timelike $p^2$ axial, the
absence of Kallen-Lehmann spectral representation obviously precludes the
existence of free quarks.


title: Pion Interferometry: Recent results from SPS

abstract:
  Recent results from the CERES experiment at the SPS are reviewed. Emphasis is
put on the centrality and beam energy dependence, and the results are put into
perspective with findings at lower and higher beam energies. The rather weak
beam energy dependence of the HBT radii maybe understood in terms of a
transition from baryon to pion dominated freeze-out. The observed short
lifetimes end emission durations are presently in contradiction to results from
model calculations.


title: Solar Magnetic Fields Profile: A Natural Consequence of RSFP Scenario

abstract:
  Assuming the solar neutrino deficit is resolved by the resonant interaction
of the neutrino magnetic moment with the solar magnetic field --in the
framework of Resonant Spin Flavour Precession (RSFP) scenario-- the solar
magnetic field profile function has been derived from the scenario in the light
of solar neutrino data. An approximate qualitative analysis has been done for
vanishing vacuum mixing and it has been found that the profile derived is quite
stable in nature. As because on changing the neutrino parameters ($\mu_{\nu},
\Delta{m^2}$) and the solar neutrino data the profile is just scaled along the
axes. In principle, the nature of the profile is strongly dependent on the
solar matter density distribution function. The current approach is quite
different from the usual one- in which the best field profile is discovered by
performing $\chi^{2}_{min.}$ calculations using solar neutrino data.
Furthermore, the profile derived in the present work --when tested by
$\chi^{2}_{min.}$ calculations-- was found to be the best suited one, for the
solar interior.


title: Probing large distance higher dimensional gravity from lensing data

abstract:
  The modifications induced in the standard weak-lensing formula if Newtonian
gravity differs from inverse square law at large distances are studied. The
possibility of putting bounds on the mass of gravitons from lensing data is
explored. A bound on graviton mass, esitmated to be about 100 Mpc$^{-1}$ is
obtained from analysis of some recent data on gravitational lensing.


title:
Do the pi N Total Cross Sections Increase Like log nu or log2 nu at High
  Energies ?

abstract:
  We propose to use rich informations on pi p total cross sections below N=10
GeV in order to investigate whether these cross sections increase like log nu
or log2 nu at high energies. A finite-energy sum rule (FESR) which is derived
in the spirit of the P' sum rule as well as the n=1 moment FESR have been
required to constrain the high-energy parameters. We then searched for the best
fit of pi p total cross sections above 70 GeV in terms of high-energy
parameters constrained by these two FESR. We can conclude that our analysis
strongly favours the log2 nu behaviors satisfying the Froissart unitarity
bound.


title:
Simultaneous Softening of sigma and rho Mesons associated with Chiral
  Restoration

abstract:
  Complex poles of the unitarized pi-pi scattering amplitude in nuclear matter
are studied. Partial restoration of chiral symmetry is modeled by the decrease
of in-medium pion decay constant f*_{pi}.
  For large chiral restoration (f*_{pi}/f_{pi} << 1),
  2nd sheet poles in the scalar (sigma) and the vector (rho) mesons are both
dictated by the Lambert W function and show universal softening as f*_{pi}
decreases.
  In-medium pi-pi cross section receives substantial contribution from the soft
mode and exhibits a large enhancement in low-energy region.
  Fate of this universality for small chiral restoration (f*_{pi}/f_{pi} ~ 1)
is also discussed.


title: Small Dirac neutrino masses in supersymmetric grand unified theories

abstract:
  A simple mechanism to generate Dirac masses for the neutrinos in SU(5)
supersymmetric grand unified theory is proposed. The tiny Dirac masses are
induced by the small mixing between the Higgs fields and another superheavy
fields. The mixing terms are obtained by the same mechanism as the mu-term
generation of the order of the supersymmetry breaking scale, so that the mixing
of order TeV / M_GUT \sim 10^{-13} is realized. We consider the lepton flavor
violating processes in this model. The branching ratios are directly related to
the neutrino oscillation parameters and we can predict the B(\tau -> \mu
\gamma) / B(\mu -> e \gamma) ratio once the neutrino oscillation parameters are
determined.


title: The proton's gluon distribution

abstract:
  The gluon distribution is dominated by the hard pomeron at small $x$ and all
$Q^2$, with no soft-pomeron contribution. This describes well not only the
DGLAP evolution of the hard-pomeron part of $F_2(x,Q^2)$, but also charm
photoproduction and electroproduction, and the longitudinal structure function,
all calculated in leading-order pQCD.


title: Perturbative QCD analysis of $B \to \phi K^* $ decays

abstract:
  We study the first observed charmless $B\to VV$ modes, the $B\to\phi K^*$
decays, in perturbative QCD formalism. The obtained branching ratios
$B(B\to\phi K^*)\sim 15 \times 10^{-6}$ are larger than $\sim 9\times 10^{-6}$
from QCD factorization. The comparison of the predicted magnitudes and phases
of the different helicity amplitudes, and branching ratios with experimental
data can test the power counting rules, the evaluation of annihilation
contributions, and the mechanism of dynamical penguin enhancement in
perturbative QCD, respectively.


title: Decay constants of heavy-light mesons in the relativistic quark model

abstract:
  The decay constants of pseudoscalar and vector heavy-light mesons are
calculated in the framework of the relativistic quark model with the completely
relativistic treatment of the light quark. It is argued that relativistic
effects play a significant role. Good agreement of the model predictions with
recent lattice and QCD sum rule calculations as well as available experimental
data is found.


title: Electron mass operator in a strong magnetic field

abstract:
  The electron mass operator in a strong magnetic field is calculated by
summation of the leading log contributions in all orders of the perturbation
theory. An influence of the strong field on the virtual photon polarization
operator is taken into account. The contribution of higher Landau levels of
virtual electrons, along with the ground Landau level, is shown to be essential
in the leading log approximation.


title: An alternative approach to b->s\gamma in the unconstrained MSSM

abstract:
  The gluino contributions to the $C'_{7,8}$ Wilson coefficients for b->s\gamma
are calculated within the unconstrained MSSM. New stringent bounds on the
\dRLbs and \dRRbs mass insertion parameters are obtained in the limit in which
the SM and SUSY contributions to $C_{7,8}$ approximately cancel. Such a
cancellation can plausibly appear within several classes of SUSY breaking
models. Assuming this cancellation takes place, we perform an analysis of the
b->s\gamma decay. We show that, in the unconstrained MSSM such an alternative
is reasonable and it is possible to saturate the b->s\gamma branching ratio and
produce a CP asymmetry of up to 20%, from only the gluino contribution to
$C'_{7,8}$ coefficients. Using photon polarization a LR asymmetry can be
defined that in principle allows the $C_{7,8}$ and $C'_{7,8}$ contributions to
the b->s\gamma decay to be disentangled.


title: Scalar Mesons and Chiral Dynamics

abstract:
  We discuss scalar mesons properties on the light of chiral dynamics.
Considering them as the chiral partners of pseudo-scalar mesons we propose an
explanation to their unusual properties based on non-trivial vacuum effects
coming from the interplay between spontaneous breaking of chiral symmetry and
the violation of $U_A(1)$ symmetry by instantons. Including vector mesons as
external sources we work out predictions for radiative decays of vector mesons
and compare some of them with recent experimental results from high luminosity
$\Phi$ factories.


title:
CP and T Trajectory Diagrams for a Unified Graphical Representation of
  Neutrino Oscillations

abstract:
  Recently the CP trajectory diagram was introduced to demonstrate the
difference between the intrinsic CP violating effects to those induced by
matter for neutrino oscillation. In this paper we introduce the T trajectory
diagram. In these diagrams the probability for a given oscillation process is
plotted versus the probability for the CP- or the T-conjugate processes, which
forms an ellipse as the CP or T violating phase is varied. Since the CP and the
T conjugate processes are related by CPT symmetry, even in the presence of
matter, these two trajectory diagrams are closely related with each other and
form a unified description of neutrino oscillations in matter.


title: Instanton Contribution to the Quark Form Factor

abstract:
  The nonperturbative effects in the quark form factor are considered in the
Wilson loop formalism. The properties of the Wilson loops with cusp
singularities are studied taking into account the perturbative and
nonperturbative contributions, where the latter are considered within the
framework of the instanton liquid model. For the integration path corresponding
to this form factor -- the angle with infinite sides -- the explicit expression
for the vacuum expectation value of the Wilson operator is found to leading
order. The calculations are performed in the weak-field limit for the instanton
vacuum contribution and compared with the one- and two-loop order results for
the perturbative part. It is shown that the instantons produce the powerlike
corrections to the perturbative result, which are comparable in magnitude with
the perturbative part at the scale of order of the inverse average instanton
size. It is demonstrated that the instanton contributions to the quark form
factor are exponentiated to high orders in the small instanton density
parameter.


title: Neutrino decay confronts the SNO data

abstract:
  We investigate the status of the neutrino decay solution to the solar
neutrino problem in the context of the recent results from Sudbury Neutrino
Observatory (SNO). We present the results of global $\chi^2$-analysis for both
two and three generation cases with one of the mass states being allowed to
decay and include the effect of both decay and mixing. We find that the Large
Mixing Angle (LMA) region which is the currently favoured solution of the solar
neutrino problem is affected significantly by decay. We present the allowed
areas in the $\Delta m^2-\tan^2\theta$ plane for different allowed values of
$\alpha$ and examine how these areas change with the inclusion of decay. We
obtain bounds on the decay constant $\alpha$ in this region which implies a
rest frame life time $\tau_0/m_{2} > 8.7 \times 10^{-5}$ sec/eV for the
unstable neutrino state. We conclude that the arrival of the neutral current
results from SNO further disfavors the neutrino decay solution to the solar
neutrino problem leaving a very small window for the decay constant $\alpha$
which could still be allowed.


title: Polyakov Loops versus Hadronic States

abstract:
  The order parameter for the pure Yang-Mills phase transition is the Polyakov
loop which encodes the symmetries of the Z_N center of the SU(N) gauge group.
On the other side the physical degrees of freedom of any asymptotically free
gauge theory are hadronic states. Using the Yang-Mills trace anomaly and the
exact Z_N symmetry we construct a model able to communicate to the hadrons the
information carried by the order parameter.


title:
Signals for black body limit in coherent ultraperipheral heavy ion
  collisions

abstract:
  We argue that study of total cross section of photoabsorption and coherent
photoproduction of $\rho,\rho^{\prime}$-mesons in ultraperipheral heavy ion
collisions (UPC) is effective method to probe onset of black body limit(BBL) in
the soft and hard QCD interactions. We illustrate the expected features of the
onset of BBL using generalized vector dominance model. We show that this model
describes very well $\rho$-meson coherent photoproduction at $6 \leq E_{\gamma}
\leq 10 GeV$. In the case of $\rho$-meson production we find a UPC cross
section which is a factor $\sim 1.5 $ larger than the one found by Klein and
Nystrand. The advantages of the process of coherent dijet production to probe
onset of BBL in hard scattering regime where decomposition over the twists
becomes inapplicable are explained and relative importance of the $\gamma
+Pomeron$ and $\gamma +\gamma$ mechanisms is estimated.


title: SUSY dark matter with non-universal gaugino masses

abstract:
  In this talk we investigate the dark matter prospects for supersymmetric
models with non-universal gaugino masses. We motivate the use of non-universal
gaugino masses from several directions, including problems with the current
favorite scenario, the cMSSM. We then display new corridors of parameter space
that allow an acceptable dark matter relic density once gaugino mass
universality is relaxed. We finish with a specific string-derived model that
allows this universality relaxation and then use the dark matter constraint to
make specific statements about the hidden sector of the model.


title: Dissociation of a Boosted Quarkonium in Quark Gluon Plasma

abstract:
  I consider the dissociation of a boosted quarkonium in a quark-gluon plasma.
This dissociation is due to absorption of a thermal gluon. I discuss the
dissociation in terms of the velocity of the quarkonium and the temperature of
the quark-gluon plasma. I compare this dissociation rate to the one calculated
without including the velocity of the quarkonium.


title:
Nucleon form factors from a covariant quark core: limits in their
  description

abstract:
  In treating the relativistic three-quark problem, a dressed-quark propagator
parameterization is used which is compatible with recent lattice data and pion
observables. Furthermore two-quark correlations are modeled as a series of
quark loops in the scalar and axialvector channel. The resulting reduced
Faddeev equations are solved for nucleon and delta. Nucleon electromagnetic
form factors are calculated in a fully covariant and gauge--invariant scheme.
Whereas the proton electric form factor $G_E$ and the nucleon magnetic moments
are described correctly, the neutron electric form factor and the ratio
$G_E/G_M$ for the proton appear to be quenched. The influence of vector mesons
on the form factors is investigated which amounts to a 25 percent modification
of the electromagnetic proton radii within this framework.


title: A QCD Primer

abstract:
  1. Introduction 2. Massless QCD and Scale Invariance 3. The Renormalisation
Group and Asymptotic Freedom 4. More on the Running Coupling 5. Application to
Hard Processes 5.1 $R_{e^+e^-}$ and Related Processes 5.2 The Final State in
$e^+e^-$ Annihilation 5.3 Deep Inelastic Scattering 5.4 Factorisation and the
QCD Improved Parton Model 6. Measurements of $\alpha_s$ 6.1 $\alpha_s$ from
$e^+e^-$ Colliders 6.2 $\alpha_s$ from Deep Inelastic Scattering 7. Conclusion
8. Appendix: The Formalism of Gauge Theories


title:
The High E_T Drop of J/psi to Drell-Yan Ratio from the Statistical c
  anti-c Coalescence Model

abstract:
  The dependence of the J/psi yield on the transverse energy E_T in heavy ion
collisions is considered within the statistical c anti-c coalescence model. The
model fits the NA50 data for Pb+Pb collisions at the CERN SPS even in the
high-E_T region (E_T > 100 GeV). Here E_T-fluctuations and E_T-losses in the
dimuon event sample naturally create the celebrated drop in the J/psi to
Drell-Yan ratio.


title: Electroweak matrix elements at large Nc: matching quarks to mesons

abstract:
  I review some progress made on the problem of calculating electroweak
processes of mesons at low energy with the use of an approximation to large-Nc
QCD which we call the Minimal Hadronic Approximation. An update of results for
the matrix elements of the electroweak penguin operators Q7 and Q8 is also
given.


title:
Path integral bosonization of the 't Hooft determinant: fluctuations and
  multiple vacua

abstract:
  The 't Hooft six quark flavor mixing interaction (N_f=3) is bosonized by the
path integral method. The considered complete Lagrangian is constructed on the
basis of the combined 't Hooft and U(3)X U(3) extended chiral four fermion
Nambu-Jona-Lasinio interactions. The method of the steepest descents is used to
derive the effective mesonic Lagrangian. Additionally to the known lowest order
stationary phase (SP) result of Reinhardt and Alkofer we obtain the
contribution from the small quantum fluctuations of bosonic configurations
around their stationary phase trajectories. It affects the vacuum state of
hadrons at low energies: whereas without the inclusion of quantum fluctuations
the vacuum is uniquely defined for a fixed set of the model parameters,
fluctuations give rise to multivalued solutions of the gap equations, marked at
instances by drastic changes in the quark condensates. We derive the new gap
equations and analyse them in comparison with known results. We classify the
solutions according to the number of extrema they may accomodate. We find up to
four solutions in the 0<m_(u,s)<3$ GeV region.


title:
The rare radiative decay $B_s \to \nu \bar{\nu} \gamma$ in beyond
  Standard Model scenarios

abstract:
  In this paper, I study the branching ratio of the rare radiative decay $B_s
\to \nu \bar{\nu} \gamma$ in the framework of the Fourth-Generation Standard
Model and the Two-Higgs-Doublet Model. It is shown that this quantity is a very
effective tool for establishing new physics beyond the Standard Model. It is
observed that there is a region in the parameter space in both extensions of
the Standard Model for which the branching ratio show considerable departure
from the Standard Model.


title: Friction in inflaton equations of motion

abstract:
  The possibility of a friction term in the equation of motion for a scalar
field is investigated in non-equilibrium field theory. The results obtained
differ greatly from existing estimates based on linear response theory, and
suggest that dissipation is not well represented by a term of the form
$\eta\dot{\phi}$.


title: Charmless Three-Body Baryonic B Decays

abstract:
  Motivated by recent data on B-> p pbar K decay, we study various charmless
three-body baryonic B decay modes, including Lambda pbar pi, Sigma0 pbar pi, p
pbar pi, p pbar Kbar0, in a factorization approach. These modes have rates of
order 10^{-6}. There are two mechanisms for the baryon pair production,
current-produced and transition. The behavior of decay spectra from these
baryon production mechanisms can be understood by using QCD counting rules.
Predictions on rates and decay spectra can be checked in the near future.


title:
Possible Hints and Search for Glueball Production in Charmless Rare B
  Decays

abstract:
  Recent data on B->p pbar K, K0 pi pi and K Kbar K hint at a $\sim 2.3$ GeV
object recoiling against a kaon. This could be the narrow state observed in
J/\psi -> gamma xi. Nonobservation in p pbar annihilation implies ${\cal B}(\xi
\to p\bar p) \sim$ few $\times 10^{-3}$, consistent with eta_c and J/\psi
decays, but there are actual hints in p pbar -> phi phi and p p-> p pi^+ pi^-
pi^+ pi^- p. Simple modeling shows ${\cal B}(B \to \xi K){\cal B}(\xi \to p\bar
p) \sim 1\times 10^{-6}$, appearing as a spike in the $p\bar p$ spectrum, with
$\sim$ 30 events per 100 fb$^{-1}$; modes such as K K_s K_s, K phi phi, K4 pi
(K f_2 pi pi) etc. should be explored. The underlying dynamics of g* -> g xi is
analogous to g* -> g etaprime or gluon fragmentation. Discovery of sizable B ->
xi K could be useful for CP violation studies.


title: Supersymmetry and Dark Matter

abstract:
  We examine supergravity models with grand unification at M_G possessing R
parity invariance. Current data has begun to significantly constrain the
parameter space. Thus for mSUGRA, accelerator data places a lower bound on
m_{1/2} of m_{1/2} >~300 GeV while astronomical data on the amount of relic
dark matter narrowly determines m_0 in terms of m_{1/2} (for fixed value of
tanbeta and A_0) due to co-annihilation effects. Additional new data could fix
the parameters further. Thus the parameter space is sensitive to the muon
magnetic moment anomaly, \delta a_\mu, and if \delta a_\mu lies 1 \sigma above
its current central value, it would exclude mSUGRA, while if it lies 1\sigma
below (but is still positive) it pushes the SUSY spectrum into the TeV domain.
The B_s ->\mu^+ \mu^- decay is seen to be accessible to the Tevatron RunII with
branching ratio sensitivity of Br[B_s ->\mu^+ \mu^-] > 6.5\times10^{-9} with 15
fb^{-1}/detector, and a value of 7(14)\times10^{-8} obtainable with 2 fb^{-1}
would be sufficient to exclude mSUGRA for tan beta < 50(55). Measurements of
B_s ->\mu^+ \mu^- can cover the full mSUGRA parameter space for tanbeta > 40 if
\delta a_\mu > 11\times10^{-10}, and combined measurements of B_s -> \mu^+
\mu^-, a_\mu and m_h (or alternately the gluino mass) would effectively
determine the mSUGRA parameters for \mu > 0. Detector cross sections are then
within the range of planned future dark matter experiments. Non-universal
models are also discussed, and it is seen that detector cross sections there
can be much larger, and can be in the DAMA data region.


title:
Search for cosmic ray sources using muons detected by the MACRO
  experiment

abstract:
  The MACRO underground detector at Gran Sasso Laboratory recorded 60 million
secondary cosmic ray muons from February 1989 until December 2000. Different
techniques were used to analyze this sample in search for density excesses from
astrophysical point-like sources. No evidence for DC excesses for any source in
an all-sky survey is reported. In addition, searches for muon excess correlated
with the known binary periods of Cygnus X-3 and Hercules X-1, and searches for
statistically significant bursting episodes from known gamma ray sources are
also proved negative.


title: Leptogenesis and Low Energy CP Violation

abstract:
  We discuss the possibility of relating the size and sign of the observed
baryon asymmetry of the universe to CP violation observable at low energies, in
a framework where the observed baryon asymmetry is produced by leptogenesis
through out of equilibrium decay of heavy Majorana neutrinos. We have shown
that although in general such a connection cannot be established, there are
specific frameworks where a link does exist. Furthermore, we identify the CP
violating phases relevant to leptogenesis and those relevant for low energy CP
violation and build weak basis invariant conditions for CP conservation.


title: Decoherence in Field Theory: General Couplings and Slow Quenches

abstract:
  We study the onset of a classical order parameter after a second-order phase
transition in quantum field theory. We consider a quantum scalar field theory
in which the system-field (long-wavelength modes), interacts with its
environment, represented both by a set of scalar fields and by its own
short-wavelength modes. We compute the decoherence times for the system-field
modes and compare them with the other time scales of the model. We analyze
different couplings between the system and the environment for slow quenches.
Within our approximations decoherence is in general a short time event.


title:
Towards the theory of coherent hard dijet production on hadrons and
  nuclei

abstract:
  We carry out a detailed calculation of the cross section of pion diffraction
dissociation into two jets with large transverse momenta, originating from a
hard gluon exchange between the pion constituents. Both the quark and the gluon
contribution are considered and in the latter case we present calculations both
in covariant and in axial gauges. We find that the standard collinear
factorization does not hold in this reaction. The structure of non-factorizable
contributions is discussed and the results are compared with the experimental
data. Our conclusion is that the existing theoretical uncertainties do not
allow, for the time being, for a quantitative extraction of the pion
distribution amplitude.


title: The MSSM Parameter Space with Non-Universal Higgs Masses

abstract:
  Without assuming that Higgs masses have the same values as other scalar
masses at the input GUT scale, we combine constraints on the minimal
supersymmetric extension of the Standard Model (MSSM) coming from the cold dark
matter density with the limits from direct searches at accelerators such as
LEP, indirect measurements such as b to s gamma decay and the anomalous
magnetic moment of the muon. The requirement that Higgs masses-squared be
positive at the GUT scale imposes important restrictions on the MSSM parameter
space, as does the requirement that the LSP be neutral. We analyze the
interplay of these constraints in the (mu, m_A), (mu, m_{1/2}), (m_{1/2}, m_0)
and (m_A, tan beta) planes. These exhibit new features not seen in the
corresponding planes in the constrained MSSM in which universality is extended
to Higgs masses.


title: Flavor Physics and Fine-Tuning in Theory Space

abstract:
  Recently a new class of composite Higgs models have been developed which give
rise to naturally light Higgs bosons without supersymmetry. Based on the chiral
symmetries of ``theory space,'' involving replicated gauge groups and
appropriate gauge symmetry breaking patterns, these models allow the scale of
the underlying strong dynamics giving rise to the composite particles to be as
large as of order 10 TeV, without any fine tuning to prevent large corrections
to Higgs boson mass(es) of order 100 GeV. In this note we show that the size of
flavor violating interactions arising generically from underlying flavor
dynamics constrain the scale of the Higgs boson compositeness to be greater
than of order 75 TeV, implying that significant fine-tuning is required.
Without fine-tuning, the low-energy structure of the composite Higgs model
alone is not sufficient to eliminate potential problems with flavor-changing
neutral currents or excessive CP violation; solving those problems requires
additional information or assumptions about the symmetries of the underlying
flavor or strong dynamics. We also consider the weaker, but more
model-independent, bounds which arise from limits on weak isospin violation.


title:
If sterile neutrinos exist, how can one determine the total solar
  neutrino fluxes?

abstract:
  The 8B solar neutrino flux inferred from a global analysis of solar neutrino
experiments is within 11% (1 sigma) of the predicted standard solar model value
if only active neutrinos exist, but could be as large as 1.7 times the standard
prediction if sterile neutrinos exist. We show that the total 8B neutrino flux
(active plus sterile neutrinos) can be determined experimentally to about 10%
(1 sigma) by combining charged current measurements made with the KamLAND
reactor experiment and with the SNO CC solar neutrino experiment, provided the
LMA neutrino oscillation solution is correct and the simulated performance of
KamLAND is valid. Including also SNO NC data, the sterile component of the 8B
neutrino flux can be measured by this method to an accuracy of about 12% (1
sigma) of the standard solar model flux. Combining Super-Kamiokande and KamLAND
measurements and assuming the oscillations occur only among active neutrinos,
the 8B neutrino flux can be measured to 6% (1 sigma); the total flux can be
measured to an accuracy of about 9%. The total 7Be solar neutrino flux can be
determined to an accuracy of about 28% (1 sigma) by combining measurements made
with the KamLAND, SNO, and gallium neutrino experiments. One can determine the
total 7Be neutrino flux to a one sigma accuracy of about 11% or better by
comparing data from the KamLAND experiment and the BOREXINO solar neutrino
experiment provided both detectors work as expected. The pp neutrino flux can
be determined to about 15% using data from the gallium, KamLAND, BOREXINO, and
SNO experiments.


title: Restrictions on dilatonic brane-world models

abstract:
  We consider dilatonic brane-world models with a non-minimal coupling between
a dilaton and usual matter on a brane. We demonstrate that variation of the
fundamental constants on the brane due to such interaction leads to strong
restrictions on parameters of models. In particular, the experimental bounds on
variation of the fine structure constant rule out non-minimal dilatonic models
with a Liouville-type coupling potential f(varphi) = exp (b varphi) where b is
order of 1.


title: Higgs boson mass limits in perturbative unification theories

abstract:
  Motivated in part by recent demonstrations that electroweak unification into
a simple group may occur at a low scale, we detail the requirements on the
Higgs mass if the unification is to be perturbative. We do this for the
Standard Model effective theory, minimal supersymmetry, and next-to-minimal
supersymmetry with an additional singlet field. Within the Standard Model
framework, we find that perturbative unification with sin2(thetaW)=1/4 occurs
at Lambda=3.8 TeV and requires mh<460 GeV, whereas perturbative unification
with sin2(thetaW)=3/8 requires mh<200 GeV. In supersymmetry, the presentation
of the Higgs mass predictions can be significantly simplified, yet remain
meaningful, by using a single supersymmetry breaking parameter Delta_S. We
present Higgs mass limits in terms of Delta_S for the minimal supersymmetric
model and the next-to-minimal supersymmetric model. We show that in
next-to-minimal supersymmetry, the Higgs mass upper limit can be as large as
500 GeV even for moderate supersymmetry masses if the perturbative unification
scale is low (e.g., Lambda=10 TeV).