title:
Failure of JoAnne's Global Fit to the Wilson Coefficients in Rare B
  Decays: A Left-Right Model Example

abstract:
  In the Standard Model and many of its extensions, it is well known that all
of the observables associated with the rare decays $b\to s\gamma$ and $b\to
s\ell^+\ell^-$ can be expressed in terms of the three Wilson coefficients,
$C_{7L,9L,10L}(\mu \sim m_b)$, together with several universal kinematic
functions. In particular it has been shown that the numerical values of these
coefficients can be uniquely extracted by a three parameter global fit to data
obtainable at future $B$-factories given sufficient integrated luminosity. In
this paper we examine if such global fits are also sensitive to new operators
beyond those which correspond to the above coefficients, i.e., whether is it
possible that new operators can be of sufficient importance for the three
parameter fit to fail and for this to be experimentally observable. Using the
Left-Right Symmetric Model as an example of a scenario with an extended
operator basis, we demonstrate via Monte Carlo techniques that such a
possibility can indeed be realized. In some sense this potential failure of the
global fit approach can actually be one of its greatest successes in
identifying the existence of new physics.


title:
Intrinsic Strange/Charmed Quarks Inside of a Strangeless/Charmless
  Hadron

abstract:
  We discuss few, apparently different, but actually tightly related problems:
a)Strangeness in the nucleon; b) B --> eta' decays; c)Intrinsic charm in the
proton spin problem. We argue that all these problems have a common origin and
related to the OZI rule violation in 0^{\pm} vacuum channels . It leads to a
noticeable role of a nonvalence component with 0^{\pm} quantum numbers in a
hadron.}


title: Backgound Gluon Effects on B -> X_s gamma gamma

abstract:
  We consider non-perturbative QCD effects on the energy spectrum of either one
of the photons in B -> X_s gamma gamma. These are due to the subprocesses in
which a charm quark loop interacts with a self-consistently produced background
static QCD field. The magnitude is estimated to be a few percents in B -> X_s
gamma gamma, but can be quite substantial in B_s -> gamma gamma. An extension
of the Euler-Heisenberg Lagrangian is given.


title:
The Schwinger Nonet Mass and Sakurai Mass-Mixing Angle Formulae
  Reexamined

abstract:
  We study the origins of the inaccuracies of Schwinger's nonet mass, and the
Sakurai mass-mixing angle, formulae for the pseudoscalar meson nonet, and
suggest new versions of them, modified by the inclusion of the pseudoscalar
decay constants. We use these new formulae to determine the pseudoscalar decay
constants and mixing angle. The results obtained, f_8/f_\pi =1.185\pm 0.040,
f_9/f_\pi =1.095\pm 0.020, f_\eta /f_\pi =1.085\pm 0.025, f_{\eta ^{'}}/f_\pi
=1.195\pm 0.035, \theta =(-21.4\pm 1.0)^o, are in excellent agreement with
experiment.


title: Estimating epsilon'/epsilon. A Review

abstract:
  The real part of epsilon'/epsilon measures direct CP violation in the decays
of the neutral kaons in two pions. It is a fundamental quantity which has
justly attracted a great deal of theoretical as well as experimental work. Its
determination may answer the question of whether CP violation is present only
in the mass matrix of neutral kaons (the superweak scenario) or also at work
directly in the decays. After a brief historical summary, we discuss the
present and expected experimental sensitivities. In the light of these, we come
to the problem of estimating epsilon'/epsilon in the standard model. We review
the present (circa 1998) status of the theoretical predictions of
epsilon'/epsilon. The short-distance part of the computation is now known to
the next-to-leading order in QCD and QED and therefore well under control. On
the other hand, the evaluation of the hadronic matrix element of the relevant
operators is where most of the theoretical uncertainty still resides. We
analyze the results of the currently most developed calculations. The values of
the B_i parameters in the various approaches are discussed, together with the
allowed range of the relevant combination of the Cabibbo-Kobayashi-Maskawa
entries Im V_{td}V^*_{ts}. We conclude by summarizing and comparing all
up-to-date predictions of epsilon'/epsilon. Because of the intrinsic
uncertainties of the long-distance computations, values ranging from 10^{-4} to
a few times 10^{-3} can be accounted for in the standard model. Since this
range covers most of the present experimental uncertainty, it is unlikely that
new physics effects can be disentangled from the standard model prediction. For
updates on the review and additional material see
http://www.he.sissa.it/review/.


title: On Orbital Angular Momentum in Deep Inelastic Scattering

abstract:
  In this work we address several issues associated with orbital angular
momentum relevant for leading twist polarized deep inelastic scattering. We
present a detailed analysis of the light-front helicity operator (generator of
rotations in the transverse plane) in QCD. We explicitly show that, the
operator constructed from the manifestly gauge invariant, symmetric energy
momentum tensor in QCD, in the gauge $A^+=0$, after the elimination of
constraint variables, is equal to the naive canonical form of the light-front
helicity operator plus surface terms. Restricting to topologically trivial
sector, we eliminate the residual gauge degrees of freedom and surface terms.
Having constructed the gauge fixed light-front helicity operator, we introduce
quark and gluon orbital helicity distribution functions relevant for polarized
deep inelastic scattering as Fourier transform of the forward hadron matrix
elements of appropriate bilocal operators. The utility of these definitions is
illustrated with the calculation of anomalous dimensions in perturbation
theory. We explicitly verify the helicity sum rule for dressed quark and gluon
targets in light-front perturbation theory. We also consider internal orbital
helicity of a composite system in an arbitrary reference frame and contrast the
results in the non-relativistic situation versus the light-front (relativistic)
case.


title: Bilinear R-Parity Violation

abstract:
  We review some of the main features of Bilinear R-Parity Violation (BRpV),
defined by a quadratic term in the superpotential which mixes lepton and Higgs
superfields and is proportional to a mass parameter epsilon. We show how large
values of epsilon can induce a small neutrino mass without fine-tunning. We
mention the effect on the mass of the lightest Higgs boson. Finally we report
on the effect of BRpV on gauge and Yukawa unification, showing that bottom-tau
unification can be achieved at any value of tan(beta).


title: Bounds on Higgs and Gauge--Boson Interactions from LEP2 Data

abstract:
  We derive bounds on Higgs and gauge--boson anomalous interactions using the
LEP2 data on the production of three photons and photon pairs in association
with hadrons. In the framework of $SU(2)_L \otimes U(1)_Y$ effective
Lagrangians, we examine all dimension--six operators that lead to anomalous
Higgs interactions involving $\gamma$ and $Z$. The search for Higgs boson
decaying to $\gamma\gamma$ pairs allow us to obtain constrains on these
anomalous couplings that are comparable with the ones originating from the
analyses of $p\bar{p}$ collisions at the Tevatron. Our results also show that
if the coefficients of all ``blind'' operators are assumed to have same
magnitude, the indirect constraints on the anomalous couplings obtained from
this analyses, for Higgs masses $M_H \lesssim$ 140 GeV, are more restrictive
than the ones coming from the $W^+W^-$ production.


title: Mixing and Decay Constants of Pseudoscalar Mesons

abstract:
  We propose a new eta-eta' mixing scheme where we start from the quark flavor
basis and assume that the decay constants in that basis follow the pattern of
particle state mixing. On exploiting the divergences of the axial vector
currents - which embody the axial vector anomaly - all basic parameters are
fixed to first order of flavor symmetry breaking. That approach naturally leads
to a mass matrix, quadratic in the masses, with specified elements. We also
test our mixing scheme against experiment and determine corrections to the
first order values of the basic parameters from phenomenology. Finally, we
generalize the mixing scheme to include the eta(c). Again the divergences of
the axial vector currents fix the mass matrix and, hence, mixing angles and the
charm content of the eta and eta'.


title:
Kaon Decay Form Factors and Atmospheric Neutrino Flavor Ratio at High
  Energies

abstract:
  The dependence of the semileptonic kaon decay form factors on the 4-momentum
transfer to the lepton pair causes certain changes in the differential decay
rates and, hence, it should affect the conventional atmospheric neutrino flux
and neutrino flavour ratio. As a case in point, we included these rates into
the calculation of the atmospheric neutrino flux at energies 1 to 100 TeV.
  The calculated neutrino spectra are between the earlier predictions while the
neutrino flavor ratio, R, is somewhat affected by the kaon form factors. The R
proves to be very sensitive to the contribution of neutrinos from decay of
charmed particles, providing an additional method to test the charm production
models in future experiments with large-volume neutrino telescopes.


title:
Next-to-leading order evolution of twist-two conformal operators: The
  abelian case

abstract:
  We present the method, based on the use of the broken conformal Ward
identities, for the calculation of the anomalous dimensions of conformal
operators beyond the leading order of perturbation theory. By means of this
technique we find the complete set of two-loop corrections to the off-diagonal
elements of the anomalous dimension matrix (the diagonal ones are known from
deep inelastic scattering calculations) of the parity odd and even singlet
local operators in the Abelian gauge theory. We reconstruct corresponding
exclusive two-loop evolution kernels and give the reduction formulae for the
restoration of the diagonal part of the ER-BL kernels from the DGLAP splitting
functions.


title: The Scalar $B\to \pi$ and $D \to \pi$ Form Factors in QCD

abstract:
  QCD sum rules on the light-cone are derived for the sum $f^+ + f^-$ of the
$B\to \pi$ and $D\to \pi$ form factors taking into account contributions up to
twist four. Combining the results with the corresponding $f^+$ form factors
calculated previously by the same method, we obtain the scalar form factors
$f^0$. Our sum rule predictions are compared with lattice results,
current-algebra constraints, and quark-model calculations. Furthermore, we
calculate decay distributions and the integrated width for the semileptonic
decay $B \to \pi \bar{\tau}\nu_\tau$ which is sensitive to $f^0$. Finally, the
dependence of the sum rules on the heavy quark mass and the asymptotic scaling
laws are discussed.


title: Vacuum engineering with DCC

abstract:
  Formation of a vacuum like domain of the strong-interaction chiral condensate
misaligned with respect to the electroweak symmetry breaking arguably modifies
the mass spectrum of electroweak gauge bosons and their interactions in that
domain in an observable manner. In particular,photon acquires the mass
$m_{\gamma}\sim{1/2}f_{\pi}\sin2\theta_{W}$.


title: Origin of the $k_T$ smearing in direct photon production

abstract:
  We show that the Sudakov factor from the resummation of double logarithms
$\ln(s/k_T^2)$ contained in the distribution functions is responsible for the
$k_T$ smearing mechanism employed in the next-to-leading-order QCD
($\alpha\alpha_s^2$) calculations of direct photon production. $s$ is the
center-of-mass energy, and $k_T$ the transverse momentum carried by a parton in
a colliding hadron. This factor exhibits the appropriate $s$-dependent Gaussian
width in $k_T$, such that our predictions are in good agreement with
experimental data.


title: Inflation

abstract:
  The shortcomings of the Standard Big Bang Cosmological Model as well as their
resolution in the context of inflationary cosmology are discussed. The
inflationary scenario and the subsequent oscillation and decay of the inflaton
field are then studied in some detail. The density perturbations produced
during inflation and their evolution during the matter dominated era are
presented. The temperature fluctuations of the cosmic background radiation are
summarized. The non-supersymmetric as well as the supersymmetric hybrid
inflationary model is introduced and the `reheating' of the universe is
analyzed in the context of the latter and a left-right symmetric gauge group.
The scenario of baryogenesis via a primordial leptogenesis is considered in
some detail. It is, finally, pointed out that, in the context of a
supersymmetric model based on a left-right symmetric gauge group, hybrid
inflation, baryogenesis via primordial leptogenesis and neutrino oscillations
are linked. This scheme, supplemented by a familiar ansatz for the neutrino
Dirac masses and mixing of the two heaviest families and with the MSW
resolution of the solar neutrino puzzle, implies that the tau-neutrino mass
lies approximately between 1 and 9 eV. The mu-tau mixing angle is predicted to
lie in a narrow range which will be partially tested by the Chorus/Nomad
experiment.


title: Renormalons as a Bridge between Perturbative and Nonperturbative Physics

abstract:
  In two lectures, we overview the renormalon and renormalon-related techniques
and their phenomenological applications. We begin with a single renormalon
chain which is a well defined and systematic way to specify the character of
corrections in inverse powers of the total energy to observables directly in
Minkowski space. Renormalons demonstrate also presence of nonperturbative
contributions. We proceed then to multirenormalon chains and argue that they
are in fact not suppressed compared to a single chain. On one hand, this
phenomenon might be a mechanism for enhancement of power corrections. On the
other hand, the derivation of relations between power corrections to various
observables becomes a formidable task and asks for introduction of models. In
the concluding, third part we consider dynamical models for nonperturbative
effects, both in infrared and ultraviolet regions, inspired by renormalons.


title:
Evidence for a Non-Zero Mass in the Dispersion Relation of Transverse
  Photons in the Stellar Core

abstract:
  The electromagnetic two-body interaction energy is modified in the thermal
environment of the solar core. The modifications are shown to imply a gross
violation of standard solar physics unless the dispersion relation \omega_t(k)
for the transverse modes of the photon is altered to include a transverse mass.
A non-zero transverse mass $m_t^2\simeq e^2 n_e/m_e$ is, of course,
theoretically predicted to exist; the discussion in this paper implies that
such a mass is required in order to maintain the success of the standard solar
model. In that sense one may claim observational evidence for a non-trivial
dispersion relation for transverse photon frequencies in the solar core.


title:
Investigation into O(N) Invariant Scalar Model Using Auxiliary-Mass
  Method at Finite Temperature

abstract:
  Using auxiliary-mass method, O(N) invariant scalar model is investigated at
finite temperature. This mass and an evolution equation allow us to calculate
an effective potential without an infrared divergence. Second order phase
transition is indicated by the effective potential. The critical exponents are
determined numerically.


title: Large N QCD

abstract:
  1. Introduction
  2. The Gross-Neveu Model
  3. QCD
  3.1 N-Counting Rules for Diagrams 3.1.1 U(1) Ghosts 3.2 The 't Hooft Model
3.3 $N$-Counting Rules for Correlation Functions 3.4 The Master Field
  4. Meson Phenomenology
  4.1 Zweig's Rule 4.2 Exotics 4.3 Chiral Perturbation Theory 4.4 Non-leptonic
K Decay 4.5 $K-\bar K$ mixing 4.6 Axial U(1) and the eta' Mass 4.7 Resonances
and 1/N
  5 Baryons 5.1 N-Counting Rules for Baryons 5.2 The Non-Relativistic Quark
Model
  6 Spin-Flavor Symmetry for Baryons
  6.1 Consistency Conditions 6.2 1/N Corrections 6.3 Solution of Consistency
Conditions
  7 Masses with SU(3) Breaking
  8 Other Results for Baryons
  9 Large N and Chiral Perturbation Theory


title: Neutrino Oscillations in the Dualized Standard Model

abstract:
  A method developed from the Dualized Standard Model for calculating the quark
CKM matrix and masses is applied to the parallel problem in neutrino
oscillations. Taking the parameters determined from quarks and the masses of
two neutrinos: $m_3^2 \sim 10^{-2} - 10^{-3} eV^2$ suggested by atmospheric
neutrino data, and $m_2^2 \sim 10^{-10} eV^2$ suggested by the long wave-length
oscillation (LWO) solution of the solar neutrino problem, one obtains from a
parameter-free calculation all the mixing angles in reasonable agreement with
existing experiment. However, the scheme is found not to accommodate
comfortably the mass values $m_2^2 \sim 10^{-5} eV^2$ suggested by the MSW
solution for solar neutrinos.


title: Inelastic Photoproduction at HERA: a Second Charmonium Crisis?

abstract:
  The measurement of the inelastic photoproduction of charmonium at HERA seems
to have ignited a new charmonium crisis. The (already discredited) color
singlet model fits the data for large charmonium energy fraction z, where the
NRQCD model qualitatively fails. We here point out that by the straightforward
inclusion of color singlet and octet processes in the soft color (color
evaporation) scheme, the HERA data can be accommodated for all z. We anticipate
that the color singlet model will fail at low z, as it does in hadroproduction.


title:
Direct Messenger-Matter Interactions in Gauge-Mediated Supersymmetry
  Breaking Models

abstract:
  We categorize general messenger and matter interactions in gauge-mediated
SUSY breaking models by an R-parity for the messengers and study their
phenomenological consequences. The new interactions may induce baryon- and
lepton-number violating processes as well as flavor-changing neutral currents.
Bounds on the couplings from low-energy data are generally weak due to the
large messenger mass suppression, except for the constraint from proton decay.
The soft masses for the scalar particles receive negative corrections from the
new interactions. Consequently, in certain region of SUSY parameter space the
\mu-parameter is greatly reduced. The pattern of radiative electroweak symmetry
breaking, SUSY particle mass spectrum and decay channels are also affected,
leading to observable experimental signature at the current and future
colliders.


title: On Random Bubble Lattices

abstract:
  We study random bubble lattices which can be produced by processes such as
first order phase transitions, and derive characteristics that are important
for understanding the percolation of distinct varieties of bubbles. The results
are relevant to the formation of topological defects as they show that infinite
domain walls and strings will be produced during appropriate first order
transitions, and that the most suitable regular lattice to study defect
formation in three dimensions is a face centered cubic lattice. Another
application of our work is to the distribution of voids in the large-scale
structure of the universe. We argue that the present universe is more akin to a
system undergoing a first-order phase transition than to one that is
crystallizing, as is implicit in the Voronoi foam description. Based on the
picture of a bubbly universe, we predict a mean coordination number for the
voids of 13.4. The mean coordination number may also be used as a tool to
distinguish between different scenarios for structure formation.


title:
Mass signature of supernova $\nu_\mu$ and $\nu_\tau$ neutrinos in
  SuperKamiokande

abstract:
  The $\nu_\mu$ and $\nu_\tau$ neutrinos (and their antiparticles) from a
Galactic core-collapse supernova can be observed in a water-\v{C}erenkov
detector by the neutral-current excitation of $^{16}$O. The number of events
expected is several times greater than from neutral-current scattering on
electrons. The observation of this signal would be a strong test that these
neutrinos are produced in core-collapse supernovae, and with the right
characteristics. In this paper, this signal is used as the basis for a
technique of neutrino mass determination from a future Galactic supernova. The
masses of the $\nu_\mu$ and $\nu_\tau$ neutrinos can either be measured or
limited by their delay relative to the $\bar{\nu}_e$ neutrinos. By comparing to
the high-statistics $\bar{\nu}_e$ data instead of the theoretical expectation,
much of the model dependence is canceled. Numerical results are presented for a
future supernova at 10 kpc as seen in the SuperKamiokande detector. Under
reasonable assumptions, and in the presence of the expected counting
statistics, $\nu_\mu$ and $\nu_\tau$ masses down to about 50 eV can be simply
and robustly determined. The signal used here is more sensitive to small
neutrino masses than the signal based on neutrino-electron scattering.


title: Is nucleon spin structure inconsistent with constituent quark model?

abstract:
  A qualitative QCD analysis and a quantitative model calculation are given to
show that the constituent quark model remains a good approximation even with
the nucleon spin structure revealed in polarized deep inelastic scattering
taking into account.


title:
Exotic mesons, locking states and their role in the formation of the
  confinement barrier

abstract:
  We discuss a mechanism by which a set of $q\bar q$-states mixes with an
exotic one, so that the exotic state accumulates the widths of the overlapping
$\bar qq$ resonances. The broad state created this way acts as a 'locking'
state for the others. Using results of a previous analysis of the
$(IJ^{PC}=00^{++})$-wave, we estimate the mean radius squared of the broad
state $f_0 (1530^{+90}_{-250})$; it appears to be distinctly larger than the
mean squared radii of the locked narrow states. This supports an idea about the
constructive role of broad states in forming the confinement barrier.


abstract:
  Photon and electron spectra in hot and dense QED are found in the high
temperature limit for all $|\q|$ using the Feynman gauge and the one-loop
self-energy. All spectra are split by the medium and their branches develop the
gap (the dynamical mass) at zero momentum. The photon spectrum has two branches
(longitudinal and transverse) with the common mass; but electron spectrum is
split on four branches which are well-separated for any $|\q|$ including their
$|\q|=0$ limits (their effective masses). These masses and the photon thermal
mass are calculated explicitly and the different limits of spectrum branches
are established in detail. The gauge invariance of the high-temperature spectra
is briefly discussed.


title:
Estimates of production rates of SUSY particles in ultra-relativistic
  heavy-ion collisions

abstract:
  We estimate the production rates of supersymmetric particles in central
heavy-ion collisions at LHC. The parton cascade model is used to seek for
possible collective phenomena which enlarge the production probability of very
heavy particles. Even if there is some indication of such cooperative effects,
higher energy and higher luminosity of proton beams at LHC disfavor heavy-ion
reactions in the search for supersymmetric particles.


title: Three-loop vacuum integrals in FORM and REDUCE

abstract:
  The implementation of an algorithm for three-loop massive vacuum integrals,
based on the explicit solution of the recurrence relations, in REDUCE and FORM
is described.


title: The Deflation of SU(3)_c at High Temperatures

abstract:
  The ideas of "local" and "global" colour-singletness are not well understood
within QCD. We use a group theoretical technique to project out the partition
function for a system of quarks, antiquarks and gluons to a particular
representation of the internal symmetry group $SU(3)_c$: colour-singlet,
colour-octet and colour 27-plet at finite temperature. For high temperatures
and large size it is shown that colour-singlet is degenerate with colour-octet,
colour 27-plet states etc. For the composite system it is shown that $SU(3)_c$
appears to be a good symmetry only at low temperatures and at higher
temperatures it gets submerged into a larger group $U(12)_q \otimes
U(12)_{\bar{q}}$ (2-flavour). At high enough temperatures this conclusion is
model independent. This means that a phase transition from the hadronic matter
to the quark-gluon phase implies a transition from the group $SU(3)_c$ to
$U(12)_q \otimes U(12)_{\bar q}$. Ideas of extensions beyond the standard model
would have to be reviewed in the light of this result.


title:
Next-to-Leading-Order Corrections to the Production of Heavy-Flavour
  Jets in e+e- Collisions

abstract:
  In this thesis we describe the calculation of the process e+ e- --> Z/gamma
-> Q Qbar + X, where Q is a heavy quark, X is anything else at order alpha_s^2.


title: Polarized Lambda-Baryon Production in pp Collisions

abstract:
  We study the production of longitudinally polarized Lambda-baryons in
single-spin pp collisions at RHIC and HERA-N as a means of determining the
spin-dependent Lambda fragmentation functions. It is shown that a measurement
of the rapidity distribution of the Lambda's would provide an excellent way of
clearly discriminating between various recently suggested sets of polarized
Lambda fragmentation functions that are all compatible with present e^+e^-
data. We also address the main theoretical uncertainties, which appear to be
well under control.


title:
Rescattering and Electroweak Penguin Effects in Strategies to Constrain
  and Determine the CKM Angle $\gamma$ from $B\to\pi K$ Decays

abstract:
  A general parametrization of the $B^+\to\pi^+ K^0$ and $B_d^0\to\pi^- K^+$
decay amplitudes is presented. It relies only on the isospin symmetry of strong
interactions and the phase structure of the Standard Model and involves no
approximations. In particular, this parametrization takes into account both
rescattering and electroweak penguin effects, which limit the theoretical
accuracy of bounds on $\gamma$ arising from the combined $B^\pm\to\pi^\pm K$,
$B_d\to\pi^\mp K^\pm$ branching ratios. Generalized bounds making also use of
the CP asymmetry in the latter decay are derived, and their sensitivity to
possible rescattering and electroweak penguin effects is investigated. It is
pointed out that experimental data on $B^\pm\to K^\pm K$ allow us to include
rescattering processes in these bounds completely, and an improved theoretical
treatment of electroweak penguins is presented. It is argued that rescattering
effects may enhance the combined $B^\pm\to K^\pm K$ branching ratio by a factor
of ${\cal O}(10)$ to the $10^{-5}$ level, and that they may be responsible for
the small present central value of the ratio of the combined $B_d\to\pi^\mp
K^\pm$ and $B^\pm\to\pi^\pm K$ branching ratios, which has recently been
reported by the CLEO collaboration and, if confirmed, would exclude values of
$\gamma$ within a large region around $90^\circ$.


title:
$B_s^0 \to D_s^-a_1^+(D_s^- \to \phi \pi^-, D_s^- \to K^{*0}K^-)$ decay
  channel in the ATLAS $B_s^0$-mixing studies

abstract:
  It is shown, using a track-level simulation, that the use of the $D_s^- \to
K^{*0}K^-$ decay channel for $D_s^-$ reconstruction, in additioon with the
previously studied $D_s^- \to \phi \pi^-$ mode, enables two fold gain in the
ATLAS $B_s^0$-mixing signal statistics through $B_s^0 \to D_s^-a_1$
$B_s^0$-decay channel. A new modification of the amplitude fit method is
suggested for the $x_s$ determination. Some general aspects of the
$B_s^0$-mixing phenomenon is illustrated by pictures of Casimir Malevich,
Maurits Cornelis Escher and Salvador Dali.


title: Spin effects in vector meson production at LEP

abstract:
  Spin observables may reveal much deeper properties of non perturbative
hadronic physics than unpolarized quantities. We discuss the polarization of
hadrons produced in $e^+e^-$ annihilation at LEP. We show how final state $q
\bar q$ interactions may give origin to non zero values of the off-diagonal
element $\rho^{\,}_{1,-1}$ of the helicity density matrix of vector mesons:
some predictions are given for $K^*, \phi, D^*$ and $B^*$ in agreement with
recent OPAL data. We also discuss the relative amount of vector and
pseudovector meson states and the probability of helicity zero vector states.
Similar measurements in other processes are suggested.


title:
Features of Quark and Lepton Mixing from Differential Geometry of Curves
  on Surfaces

abstract:
  It is noted that the CKM matrix elements for both quarks and leptons as
conceived in the Dualized Standard Model (DSM) can be interpreted as direction
cosines obtained by moving the Darboux trihedron (a 3-frame) along a trajectory
on a sphere traced out through changing energy scales by a 3-vector factorized
from the mass matrix. From the `Darboux' analogues of the well-known
Serret--Frenet formulae for space curves, it is seen that the corner elements
($V_{ub}, V_{td}$ for quarks, and $U_{e3}, U_{\tau 1}$ for leptons) are
associated with the (geodesic) torsion, while the other off-diagonal elements
($V_{us}, V_{cd}$ and $V_{cb}, V_{ts}$ for quarks, and $U_{e2}, U_{\mu 1}$ and
$U_{\mu 3}, U_{\tau 2}$ for leptons) with the (respectively geodesic and
normal) curvatures of the trajectory. From this it follows that (i) the corner
elements in both matrices are much smaller than the other elements, (ii) the
$U_{\mu 3}, U_{\tau 2}$ elements for the lepton CKM matrix are much larger than
their counterparts in the quark matrix. Both these conclusions are strongly
borne out by experiment, for quarks in hadron decays and for leptons in
neutrino oscillations, and by previous explicit calculations within the DSM
scheme.


title: A Modern Anatomy of Electron Mass

abstract:
  Motivated by the need to understand hadron masses, we reexamine an old
problem in QED - the composition of the electron mass - in a modern
perspective. We find that in the unrenormalized QED, the vacuum subtraction
plays an important role in understanding various sources of the electron mass.
The same issue is also discussed in the modified minimal subtraction scheme
with an emphasis on the scale and scheme dependence in the analysis.


title: Fracture Functions and Jet Calculus

abstract:
  By using Jet Calculus as a consistent framework to describe multiparton
dynamics we explain the peculiar evolution equation of fracture functions by
means of the recently introduced extended fracture functions.


title: The Singular Behaviour of QCD Amplitudes at Two-loop Order

abstract:
  We discuss the structure of infrared singularities in on-shell QCD amplitudes
at two-loop order. We present a general factorization formula that controls all
the $\ep$-poles of the dimensionally regularized amplitudes. The dependence on
the regularization scheme is considered and the coefficients of the $1/\ep^4,
1/\ep^3$ and $1/\ep^2$ poles are explicitly given in the most general case. The
remaining single-pole contributions are also explicitly evaluated in the case
of amplitudes with a $q{\bar q}$ pair.


title:
Gluon production in current-nucleus and nucleon-nucleus collisions in a
  quasi-classical approximation

abstract:
  We calculate gluon production in deep inelastic scattering of the current j=
- (1/4) F_{\mu\nu}^a F_{\mu\nu}^a off a large nucleus and in nucleon-nucleus
collisions. In a covariant gauge calculation the transverse momentum spectrum
of the gluon is determined by the final state interactions of the gluon with
the nucleons in the nucleus. In a light-cone gauge calculation final state
interactions are absent and these effects come from the light-cone wavefunction
of the nucleus. We work in an approximation which neglects QCD evolution of
gluons in the nucleon, that is in a quasi-classical approximation.


title: Supersymmetry Reach of Tevatron Upgrades: The Large $\tan\beta$ Case

abstract:
  The Yukawa couplings of the tau lepton and the bottom quark become comparable
to, or even exceed, electroweak gauge couplings for large values of the SUSY
parameter $\tan\beta$. As a result, the lightest tau slepton $\ttau_1$ and
bottom squark $\tb_1$ can be significantly lighter than corresponding sleptons
and squarks of the first two generations. Gluino, chargino and neutralino
decays to third generation particles are significantly enhanced when
$\tan\beta$ is large. This affects projections for collider experiment reach
for supersymmetric particles. In this paper, we evaluate the reach of the
Fermilab Tevatron $p\bar p$ collider for supersymmetric signals in the
framework of the mSUGRA model. We find that the reach via signatures with
multiple isolated leptons ($e$ and $\mu$) is considerably reduced. For very
large $\tan\beta$, the greatest reach is attained in the multi-jet$+\eslt$
signature. Some significant extra regions may be probed by requiring the
presence of an identified $b$-jet in jets$+\eslt$ events, or by requiring one
of the identified leptons in clean trilepton events to actually be a hadronic 1
or 3 charged prong tau. In an appendix, we present formulae for chargino,
neutralino and gluino three body decays which are valid at large $\tan\beta$.


title:
Suppression of Bremsstrahlung and Pair Production due to Environmental
  Factors

abstract:
  The environment in which bremsstrahlung and pair creation occurs can strongly
affect cross sections for these processes. Because ultra-relativistic
electromagnetic interactions involve very small longitudinal momentum
transfers, the reactions occur gradually, spread over long distances. During
this time, even relatively weak factors can accumulate enough to disrupt the
interaction.
  This review will discuss a variety of factors which can suppress
bremsstrahlung and pair production, as well as related effects involving
beamstrahlung and QCD processes. After surveying different theoretical
approaches, experimental measurements from the early cosmic ray studies to the
recent detailed measurements by the SLAC E-146 collaboration will be discussed.


title: A Signature of Inflation from Dynamical Supersymmetry Breaking

abstract:
  In models of cosmological inflation motivated by dynamical supersymmetry
breaking, the potential driving inflation may be characterized by inverse
powers of a scalar field. These models produce observables similar to those
typical of the hybrid inflation scenario: negligible production of tensor
(gravitational wave) modes, and a blue scalar spectral index. In this short
note, we show that, unlike standard hybrid inflation models, dynamical
supersymmetric inflation (DSI) predicts a measurable deviation from a power-law
spectrum of fluctuations, with a variation in the scalar spectral index $|dn /
d(\ln k)|$ may be as large as 0.05. DSI can be observationally distinguished
from other hybrid models with cosmic microwave background measurements of the
planned sensitivity of the ESA's Planck Surveyor.


title: Quark Mass Hierarchy and Flavor Mixing

abstract:
  In view of the observed strong hierarchy of the quark and lepton masses and
of the flavor mixing angles it is argued that the description of flavor mixing
must take this into account. One particular interesting way to describe the
flavor mixing, which, however, is not the one used today, emerges, which is
best suited for models of quark mass matrices based on flavor symmetries. We
conclude that the unitarity triangle important for $B$ physics should be close
to or identical to a rectangular triangle. CP violation is maximal in this
sense.


title: Neutrino Masses and Leptogenesis with Heavy Higgs Triplets

abstract:
  A simple and economical extension of the minimal standard electroweak gauge
model (without right-handed neutrinos) by the addition of two heavy Higgs
scalar triplets would have two significant advantages. \underline {Naturally}
small Majorana neutrino masses would become possible, as well as leptogenesis
in the early universe which gets converted at the electroweak phase transition
into the present observed baryon asymmetry.


title: Next-to-leading order corrections to gauge-mediated gaugino masses

abstract:
  We compute the next-to-leading order corrections to the gaugino masses $M_i$
in gauge-mediated models for generic values of the messenger masses M and
discuss the predictions of unified messenger models. If M<100 TeV there can be
up to 10% corrections to the leading order relations $M_i\propto \alpha_i$. If
the messengers are heavier there are only few % corrections. We also study the
messenger corrections to gauge coupling unification: as a result of
cancellations dictated by supersymmetry, the predicted value of the strong
coupling constant is typically only negligibly increased.


title: Finite Energy Chiral Sum Rules and Tau Spectral Functions

abstract:
  A combination of finite energy sum rule techniques and Chiral Perturbation
Theory (ChPT) is used in order to exploit recent ALEPH data on the non-strange
tau vector (V) and axial-vector (A) spectral functions with respect to an
experimental determination of the ChPT quantity L_{10}. A constrained fit of
R_{\tau,V-A}^(k,l) inverse moments (l<0) and positive spectral moments (l>=0)
adjusts simultaneously L_{10} and the nonperturbative power terms of the
Operator Product Expansion. We give explicit formulae for the first k=0,1 and
l=-1,-2 strange and non-strange inverse moment chiral sum rules to one-loop
order generalized ChPT. Our final result reads L^r_{10}(M_\rho)=-(5.13 +/-
0.19)x10^{-3}, where the error includes experimental and theoretical
uncertainties.


title: An Introduction to Sum Rules in QCD

abstract:
  Contents: 1. Introduction. 2. Sum rules prior to QCD. 3. Dispersion
relations. 4. Types of two point function sum rules. 5. Non-perturbative power
corrections.
  6. Some examples of QCD sum rules.


title: Resolved Electron

abstract:
  Advantages of introducing the electron structure function in electron induced
processes are demonstrated. At present energies the same experiment gives more
precise description of the electron than photon structure. The momentum scales
entering the process are better controlled. At very high momenta probabilistic
(partonic) interpretation can be preserved despite strong \gamma -Z
interference. The ``virtual photon'' structure can also be reformulated in
terms of more physical (real) electron variables.


title: Prolonged Decay and CP-asymmetry

abstract:
  Time evolution of unstable particles that occur in the expanding universe is
investigated. The off-shell effect not included in the Boltzmann-like equation
is important for the decay process when the temperature becomes much below the
mass of unstable particle. When the off-shell effect is taken into account, the
thermal abundance of unstable particles at low temperatures has a power law
behavior of temperature $T$, $\frac{\Gamma}{M}(\frac{T}{M})^{\alpha + 1}$
unlike the Boltzmann suppressed $e^{-M/T}$, with the power $\alpha $ related to
the spectral rise near the threshold of the decay and with $\Gamma $ the decay
rate. Moreover, the relaxation time towards the thermal value is not governed
by the exponential law; instead, it is the power law of time. The evolution
equation for the occupation number and the number density of the unstable
particle is derived, when both of these effects, along with the cosmic
expansion, are included. We also critically examine how the scattering off
thermal particles may affect the off-shell effect to the unstable particle. As
an application showing the importance of the off-shell effect we compute the
time evolution of the baryon asymmetry generated by the heavy $X$ boson decay.
It is shown that the out-of equilibrium kinematics previously discussed is
considerably changed.


title: Gauge invariance of the resummation approach to evolution equations

abstract:
  We show that the Collins-Soper-Sterman resummation approach to the derivation
of the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi equation is gauge invariant.
The special gauge-dependent parton distribution function employed in the
resummation technique is expressed as the convolution of an infrared finite
function with the standard distribution function. By means of this convolution
relation, we explain how the technique works in summing large logarithmic
corrections, and how the gauge invariance of the special distribution function
is restored.


title: More Signatures of the Intermediate Mass Higgs Boson

abstract:
  We examine the potential signatures of the Higgs boson when it decays into a
tau-lepton pair. We show that with the proper identification of the tau-jet,
this decay mode can lead to the identification of the Higgs boson over most of
the intermediate mass range (\mW $<$ \mH $<$ 2 \mW).


title: Does the QGP fire ball really exist?

abstract:
  The strongly interacting matter under extreme conditions of temperature for
the conjectured deconfined phase of the quark-gluon plasma is investigated. A
systematic study of the form of the thermal ratio of the disorder deviation
(TRDD) is presented with the emphasis on the degree of deviation of the
TRDD-function from unity. The space-time evolution of quarks and gluons is
studied in the framework of two-particle correlation functions to predict the
space-time size of the closed deconfined phase.


title: Supersymmetric U(1) at the TeV Scale

abstract:
  If there exists an arbitrary supersymmetric U(1) gauge factor at the TeV
scale, under which the two Higgs superfields H_{1,2} of the standard model are
nontrivial, and if there is also a singlet superfield S such that the H_1 H_2 S
term is allowed in the superpotential, then the structure of the two-doublet
Higgs sector at the electroweak scale is more general than that of the MSSM
(Minimal Supersymmetric Standard Model). Under further assumptions of grand
unification and universal soft supersymmetry breaking terms, the scale of U(1)
breaking is related to the parameter tan(beta) = v_2/v_1.


title: Neutrino Masses and Anomalous Interactions

abstract:
  The interplay between neutrino masses and the interactions of neutrinos with
matter is discussed with an eye to extending the latter to include possible new
interactions. This conjecture may resolve the conundrum posed by the present
experimental data on neutrino oscillations which suggest the existence of four
neutrinos, whereas Z decay and Big Bang Nucleosynthesis allow only three. The
case of a possible sterile neutrino is also briefly discussed.


title: Models of Neutrino Mass and Interactions for Neutrino Oscillations

abstract:
  I review the various mechanisms for obtaining nonzero neutrino masses. I
focus on the possibility of adding one light singlet neutrino to the three
known doublet neutrinos nu_e, nu_mu, and nu_tau to accommodate the totality of
neutrino-oscillation experiments. I review the various theoretical suggestions
for this singlet. I discuss also a scenario in which there are only the three
doublet neutrinos but a large anomalous interaction is assumed for nu_tau as an
attempt to explain all present data.


title:
Symmetries of the Standard Model without and with a Right-Handed
  Neutrino

abstract:
  Given the particle content of the standard model without and with a
right-handed neutrino, the requirement that all anomalies cancel singles out a
set of possible global symmetries which can be gauged. I review this topic and
propose a new gauge symmetry B - 3L_tau in the context of the minimal standard
model consisting of the usual three families of quarks and leptons plus just
one nu_R. The many interesting phenomenological consequences of this hypothesis
are briefly discussed.


title: Confinement from a massive scalar in QCD

abstract:
  A model is introduced with a massive scalar coupling to the Yang--Mills term
in four--dimensional gauge theory. It is shown that the resulting potential of
colour sources consists of a short range Coulomb interaction and a long range
confining part. Far away from the source the scalar vanishes $\sim r^{-1}$
while the potential diverges linearly $\sim r$. Up to an $N_c$--dependent
factor of order 1 the tension parameter in the model is $gmf$, where $m$
denotes the mass of the scalar and $f$ is a coupling scale entering the
scalar--gluon coupling.


title: Radiative Corrections to a Supersymmetric Relation: A New Approach

abstract:
  Recently it has been realized that the production and decay processes of
charginos, neutralinos, and sleptons receive corrections which grow like log
m_squark for large m_squark. In this paper we calculate the chargino pair
production cross section at e+e- colliders with quark/squark loop corrections.
We introduce a novel formulation, where the one-loop amplitude is reorganized
into two parts. One part is expressed in terms of the ``effective'' chargino
coupling gbar and mixing matrices U^P, V^P, and includes all O(log m_squark)
corrections, while the other decouples for large m_squark. The form of the
one-loop cross section then becomes physically transparent. Our formulation can
be easily extended to other loops and processes. Numerically, we find
significant corrections due to the effective t-channel coupling gbar, for
gaugino-like charginos. In the mixed region, where the chargino has large
gaugino and Higgsino components, the corrections due to (U^P,V^P) are also
significant. Our numerical results disagree with a previous calculation. We
revisit previous studies of the determination of gbar through the measurement
of the chargino production cross section. We point out that a previous study,
which claimed that the measurement suffers large systematic errors, was
performed at a ``pessimistic'' point in MSSM parameter space. We provide
reasons why the systematic errors are not a limiting factor for generic
parameter choices.


title: O(\alpha^n\alpha_s^m) Corrections in e^+e^- Annihilation and \tau Decay

abstract:
  The results of evaluation of mixed QED X QCD corrections to R(s) in e^+e^-
annihilation and R_{\tau} in hadronic decay of the \tau lepton to
O(\alpha^n\alpha_s^m), m+n \leq 3, are presented. The net effect on
\alpha_s(M_Z) from the Z decay is only about 0.1% and in the \tau decay case
the net effect is negligible, as expected.


title:
Effects of Matter Density Fluctuation in Long Baseline Neutrino
  Oscillation Experiments

abstract:
  The effects of matter density fluctuation in long baseline neutrino
oscillation experiments are studied. Effects of short wavelength fluctuations
are in general irrelevant. Effects of long wavelength fluctuations must be
checked on a case-by-case basis. As an example we checked the fluctuation
effects and showed its irrelevance in a case of K2K experiments.


title:
Non-perturbative solutions of the SD equation for an Abelian gauge field
  theory

abstract:
  In this article we present a mechanism in which we find new non-perturbative
solutions of quantum electrodynamics in four dimensions. Two non-perturbative
solutions are found for approximate Schwinger-Dyson equations. The mass ratio
of the three solutions (one is ordinary solution) is approximately
$1:(8\pi/\alpha)^{2/3}:8\pi/\alpha$.


title: The phi --> gamma K0 bar(K0) Decay

abstract:
  The study of the process phi-->gamma K0 bar(K0) is calculated to be 5.10^(-8)
in a scheme which takes into account the different isospin channels involved,
I=0,1 with the resonant, f_0(980), a_0(980), and non resonant contributions.


title: Electroweak Phase Transitions in left-right symmetric models

abstract:
  We study the finite-temperature effective potential of minimal left-right
symmetric models containing a bidoublet and two triplets in the scalar sector.
We perform a numerical analysis of the parameter space compatible with the
requirement that baryon asymmetry is not washed out by sphaleron processes
after the electroweak phase transition. We find that the spectrum of scalar
particles for these acceptable cases is consistent with present experimental
bounds.


title: Quantum Corrections to the QED Vacuum Energy

abstract:
  At energies much less than the electron mass $m$ the effects of quantum
fluctuations in the vacuum due to virtual electron loops can be included by
extending the Maxwell Lagrangian by additional non-renormalizable terms
corresponding to the Uehling and Euler-Heisenberg interactions. This effective
field theory is used to calculate the properties of the QED vacuum at
temperatures $T << m$. By a redefinition of the electromagnetic field, the
Uehling term is shown not to contribute. The Stefan-Boltzmann energy density is
thus found to be modified by a term proportional with $T^8/m^4$ in agreement
with the semi-classical result of Barton. The speed of light in blackbody
radiation is smaller than one. Similarly, the correction to the energy density
of the vacuum between two metallic parallel plates diverges like $1/m^4z^8$ at
a distance from one of the plates $z \to 0$. While the integral of the
regularized energy density is thus divergent, the regularized integral is
finite and corresponds to a correction to the Casimir force which varies with
the separation $L$ between the plates as $1/m^4L^8$. This result is in
seemingly disagreement with a previous result for the radiative correction to
the Casimir force which gives a correction varying like $1/mL^5$ in a
calculation using full QED.


title: Gauge-Yukawa-Finite Unified Theories and their Predictions

abstract:
  Gauge-Yukawa unified theories, and in particular those which are finite
beyond the unification scale, have been extended to include a soft
supersymmetry breaking (SSB) sector. In the case of the Finite Unified Theories
a new solution to the condition of two-loop finiteness of the SSB parameters is
found, which requires a sum rule for the relevant scalar masses. The sum rule
permits violations of the universality of the scalar masses which is found to
lead to phenomenological problems. The minimal supersymmetric SU(5)
Gauge-Yukawa model and two Finite-Gauge-Yukawa models have been examined using
the sum rule. The characteristic features of these models are: a) the old
agreement of the top quark mass prediction persists using the new data, b) the
lightest Higgs boson is predicted to be around 120 GeV, c) the s-spectrum
starts above 200 GeV.


title: On Metastability in Supersymmetric Models

abstract:
  We make a critical reappraisal of `unbounded-from-below' (UFB) constraints in
the MSSM and R-parity violating models. We explain why the `traditional' UFB
bounds are neither necessary nor sufficient and propose, instead, a sufficient
condition which ensures that there are no local minima along the flat
directions. This conservative (but meaningful) condition divides the parameter
space into regions which are allowed, regardless of cosmology, and regions in
which cosmology is expected to play a major role. We study both conditions at
low tan-beta and obtain analytic approximations to the UFB bounds for all low
tan-beta (<15). Finally we show that R-parity violation just below current
experimental limits avoids UFB problems by lifting the dangerous flat
directions.


title: Models of Electroweak Symmetry Breaking

abstract:
  Discovering the dynamics responsible for electroweak symmetry breaking is the
outstanding question facing particle physics today, and the answer will be
found in the next decade. In these lectures I discuss the range of models which
have been proposed to explain electroweak symmetry breaking. I begin with an
overview of Higgs models, with emphasis on the naturalness/hierarchy and
triviality problems, and then consider general lessons which can be drawn about
the symmetry breaking sector in arbitrary scalar models. Subsequently, I
discuss the symmetry breaking sector in supersymmetric models and then consider
models of dynamical electroweak symmetry breaking. I conclude with a brief
review of the open questions.


title:
Energy Dependence of Solar Neutrino Suppression and Bounds on the
  Neutrino Magnetic Moment

abstract:
  An analysis of neutrino electron scattering as applied to the SuperKamiokande
solar neutrino experiment with the data from the Homestake experiment leads to
an upper bound on the neutrino magnetic moment in the range
$\mu_{\nu_e}\leq(2.9-3.7)\times 10^{-10}\mu_{B}$. This range is determined by
the spread in the flux predictions from six different standard solar models. We
assume equal magnetic moments for all neutrino flavours. This limit is obtained
when neutrinos do not undergo any "disappearance" mechanism other than the
magnetic moment conversion due to the solar magnetic field and for a total or
nearly total suppression of the intermediate energy neutrinos. We also point
out that the limit may be further reduced if the threshold energy of the
SuperKamiokande detector is decreased.


title: K^* Mesons and Nucleon Strangeness

abstract:
  We study contributions to the nucleon strange quark vector current form
factors from intermediate states containing K^* mesons. We show how these
contributions may be comparable in magnitude to those made by K mesons, using
methods complementary to those employed in quark model studies. We also analyze
the degree of theoretical uncertainty associated with K^* contributions.


title: Probing Exotic Higgs Sectors in $\ell^-\ell^-$ Collisions

abstract:
  I review extended Higgs sectors and constraints thereon arising from
$\rho=1$, gauge-coupling unification and $b\to s\gam$. The couplings and decays
of the Higgs boson eigenstates are outlined for triplet representations. Direct
experimental probes of exotic Higgs bosons are reviewed with a focus on the
important role that would be played by an $e^-e^-$ or $\mu^-\mu^-$ collider.


title:
Cosmic Topological Defects, Highest Energy Cosmic Rays, and the Baryon
  Asymmetry of the Universe

abstract:
  It is pointed out that the observed extremely high energy cosmic rays (EHECR)
above $10^{11}$ GeV and the observed baryon asymmetry of the Universe (BAU),
both may have a common origin in baryon number violating decays of supermassive
``X'' particles released from cosmic topological defects (TDs) such as cosmic
strings and monopoles. The X particles produced by TDs in the recent epochs
produce the EHECR, while the BAU is created by X particles released from TDs
mainly in the very early Universe. In this scenario the EHECR is predicted to
contain baryons as well as antibaryons with a small asymmetry between the two.


title: Nonleptonic decays: Amplitude analysis and supermultiplet schemes

abstract:
  We give best covariant amplitude decompositions for two-body decay processes
involving ground state hadrons ($0^-, 1^-, {1/2}^+, {3/2}^+$) and show how
these are simply related to helicity amplitudes. After discussing how
electromagnetic interactions are incorporated via meson dominance in a
relativistic supermultiplet scheme, we extend the analysis to weak flavour
changing nonleptonic processes. Such weak interactions are described by three
generic amplitudes, which we estimate according to the rules of calculation
within covariant SU(2N$_f$).


title:
Spin content of Lambda and its longitudinal polarization in $e^+e^-$
  annihilation at high energies

abstract:
  Longitudinal polarization of Lambda produced in $e^+e^-$ annihilation at LEP
energies is calculated in a picture for the spin content of Lambda which is
consistent with the polarized deep inelastic lepton-nucleon scattering data and
SU(3) flavor symmetry for hyperon decay so that the spin of Lambda is not
completely carried by its $s$-valence quark. A comparison with the recent ALEPH
data and the results of earlier calculations based on the static quark model in
which the spin of Lambda is completely determined by the $s$-quark is given.
The result shows that further measurements of such polarization should provide
useful information to the question of which picture is more suitable in
describing the spin effects in the fragmentation processes.


title: Optimized Perturbation Theory at Finite Temperature

abstract:
  An optimized perturbation theory (OPT) at finite temperature T, which resums
higher order terms in the naive perturbation, is developed in O(N) phi^4
theory. It is proved that (i) the renormalization of the ultra-violet
divergences can be carried out systematically in any given order of OPT, and
(ii) the Nambu-Goldstone theorem is fulfilled for arbitrary N and for any given
order of OPT.
  The method is applied for the O(4) sigma model to study the soft modes
associated with the chiral transition in quantum chromodynamics. Threshold
enhancement of the spectral functions at finite T in the scalar and
pseudo-scalar channels is shown to be a typical signal of the chiral
transition.


title: Extraction of the D^*D\pi coupling from D^* decays

abstract:
  The decays D^* -> D\pi and D^* -> D\gamma are well described by heavy meson
chiral perturbation theory. With the recent measurement of Br(D^{*+} -> D^+
\gamma), the D^{*0}, D^{*+}, and D_s^* branching fractions can be used to
extract the D^*D\pi and D^*D\gamma couplings $g$ and $\beta$. The D^* ->
D\gamma decays receive important corrections at order $\sqrt{m_q}$ and, from
the heavy quark magnetic moment, at order $1/m_c$. Here all the decay rates are
computed to one-loop, to first order in $m_q$ and $1/m_c$, including the effect
of heavy meson mass splittings, and the counterterms at order $m_q$. A fit to
the experimental data gives two possible solutions,
g=0.27^{+.04}_{-.02}^{+.05}_{-.02}, \beta=0.85^{+.2}_{-.1}^{+.3}_{-.1} GeV^{-1}
or g=0.76^{+.03}_{-.03}^{+.2}_{-.1}, \beta=4.90^{+.3}_{-.3}^{+5.0}_{-.7}
GeV^{-1}. The first errors are experimental, while the second are estimates of
the uncertainty induced by the counterterms. (The experimental limit
\Gamma_{D^{*+}} < 0.13 MeV excludes the $g=0.76$ solution.) Predictions for the
D^* and B^* widths are given.


title:
Limits on tan beta in SU(5) GUTs with Gauge-Mediated Supersymmetry
  Breaking

abstract:
  By considering the constraints from nucleon decay we obtain upper limits on
tan beta in generalized supersymmetric SU(5) grand unified theories with
gauge-mediated supersymmetry breaking. We find that the predicted values of tan
beta in these models are mostly inconsistent with the constraints from nucleon
decay.


title: Polarized Quarks, Gluons and Sea in Nucleon Structure Functions

abstract:
  We perform a NLO analysis of polarized deep inelastic scattering data to test
two different solutions to the so called spin crisis: one of them based on the
axial gluon anomaly and consistent with the Bjorken sum rule and another one,
where the defects in the spin sum rules and in the Gottfried sum rule are
related. In this case a defect is also expected for the Bjorken sum rule. The
first solution is slightly favoured by the SLAC E154 results, but both options
seem to be consistent with the CERN SMC data.


title: Single spin asymmetries in semi-inclusive deep inelastic scattering

abstract:
  In this talk I want to illustrate the many possibilities for studying the
structure of hadrons in hard scattering processes by giving a number of
examples involving increasing complexity in the demands for particle
polarization, particle identification or polarimetry. In particular the single
spin asymmetries will be discussed. The measurements discussed in this talk are
restricted to lepton-hadron scattering, but can be found in various other hard
processes such as Drell-Yan scattering or $e^+e^-$-annihilation.


title:
The next to leading order effective potential in the 2+1 dimensional
  Nambu-Jona-Lasinio model at finite temperature

abstract:
  The finite temperature effective potential in the 2+1 dimensional
Nambu-Jona-Lasinio model is constructed up to the next to leading order in the
large $N$ expansion, where $N$ is the number of flavors in the model. The
distinctive feature of the analysis is an inclusion of an additional scalar
field, which allows us to circumvent the well known, and otherwise unavoidable
problem with the imaginary contribution to the effective potential. In
accordance with the Mermin-Wagner-Coleman theorem, applied to the dimensionally
reduced subsystem of the zero Matsubara modes of the composite boson fields,
the finite temperature effective potential reveals a global minimum at the zero
of the composite order parameter. This allows us to conclude that the
continuous global symmetry of the NJL model is not broken for any arbitrarily
small, finite temperature.


title: The Extended Chiral Quark Model and QCD

abstract:
  We consider the low energy effective action of QCD below the chiral symmetry
breaking scale, including, in Wilson's spirit, all operators of dimensionality
less or equal to 6 which can be built with quark and chiral fields. The effect
of the residual gluon interactions is contained in a number of coupling
constants, whose running is studied. The resulting model is an extension of
both the chiral quark model and the Nambu-Jona-Lasinio one. Constraints on the
coefficients of the effective lagrangian are derived from the requirement of
chiral symmetry restoration at energies above the chiral symmetry breaking
scale, from matching to QCD at intermediate scales, and by fitting some
hadronic observables. In this model two types of pseudoscalar states (massless
pions and massive \Pi-mesons), as well as one scalar one arise as a consequence
of dynamical chiral symmetry breaking. Their masses and coupling constants are
studied. We also predict a number of low energy structural constants. We find
out that QCD favours a low-energy effective theory which is largely dominated
by the simplest chiral quark model, whereas higher dimensional operators (such
as those of the Nambu-Jona-Lasinio type) can be assumed to be small.


title: Sigma-fields x Chiral Scalars in Nuclear Three Body Potentials

abstract:
  The scalar-isoscalar field of an effective chiral Lagrangian transforms
differently in either linear or non-linear frameworks: in the former case it is
the counterpart of the pion whereas in the latter it is chiral invariant on its
own. We compare the predictions from these two models for nucleon interactions
and find results which are identical for two-body and rather different for
three-body potentials. Some qualitative features of three-body interactions are
discussed.


title: Thermal Phase Transition in Weakly Interacting Large N_C QCD

abstract:
  We consider thermal QCD in the large N_C limit, mainly in 1+1 dimensions.
  The gauge coupling is only taken into account to minimal order, by projection
onto colour singlets. An expression for the free energy, exact as N_C goes to
infinity, is then obtained. A third order phase transition will occur. The
critical temperature depends on the ratio N_C/L, where L is the (infinite)
spatial length. In the high temperature limit, the free energy will approach
the same value as in the free theory, whereas we have a mesonic like phase at
low temperature. Expressions for the quark condensate, <\bar\Psi \Psi >, are
also obtained.


title: When to carry out analytic continuation?

abstract:
  This paper discusses the analytic continuation in the thermal field theory by
using the theory of $\eta-\xi$ spacetime. Taking a simple model as example, the
$2\times 2$ matrix real-time propagator is solved from the equation obtained
through continuation of the equation for the imaginary-time propagator. The
geometry of the $\eta-\xi$ spacetime plays important role in the discussion.


title: Local duality and nonleptonic B decay

abstract:
  In the large $N_c$ limit, the nonleptonic width of the B meson is determined
by the lepton mass spectrum in semileptonic B decay and the hadron mass
spectrum in $\tau$ decay. This result can be compared with the nonleptonic
width computed using the operator product expansion and local duality, to
estimate the violation of local duality in B decay. In the absence of the
required data, we use experimental Monte Carlo predictions and find that the
difference is small, at the few percent level. We estimate the theoretical
uncertainty in our results from higher order corrections (including $1/N_c$
effects). We also identify a new contribution to the $\Lambda_b-B$ lifetime
difference.


title: Theoretical Analysis of Polarized Structure Functions

abstract:
  We review the analysis of polarized structure function data using
perturbative QCD at next-to-leading order. We use the most recent experimental
data to obtain updated results for polarized parton distributions, first
moments and the strong coupling. We also discuss several theoretical issues
involved in this analysis and in the interpretation of its results. Finally, we
compare our results with other similar analyses in the recent literature.


title: Positivity of NLO Spin-Dependent Parton Distributions

abstract:
  We discuss the positivity of the hadron density matrix in QCD. This basic
property is shown to be preserved by QCD evolution, provided the relation
$|\Delta P_{ij}(z)| \leq P_{ij}$ is valid for all kernels for $z < 1$, and the
usual "+" prescription is used. We comment on the positivity restrictions for
the choice of the NLO factorization scheme for the evolution of the
spin-dependent parton distributions.


title: Relativistic Transport Theory for Systems Containing Bound States

abstract:
  Using a Lagrangian which contains quarks as elementary degrees of freedom and
mesons as bound states, a transport formalism is developed, which allows for a
dynamical transition from a quark plasma to a state, where quarks are bound
into hadrons. Simultaneous transport equations for both particle species are
derived in a systematic and consistent fashion. For the mesons a formalism is
used which introduces off-shell corrections to the off-diagonal Green
functions. It is shown that these off-shell corrections lead to the appearance
of elastic quark scattering processes in the collision integral. The
interference of the processes $q\bar q\to\pi$ and $q\bar q\to\pi\to q\bar q$
leads to a modification of the $s$-channel amplitude of quark-antiquark
scattering.


title: Study of Fractality and Chaoticity in Central 4.5A GeV/c C-Cu Collisions

abstract:
  Multifractality of charged particle pseudorapidity distributions is analyzed
in central collisions of carbon and copper nuclei at 4.5 GeV/c per nucleon.
Within the method of normalized factorial moments, modified to remove the bias
of infinite statistics in the normalization, intermittency-like behavior
(scaling) is observed up to eight-particle fluctuations. The study indicates a
possible non-thermal phase transition inside cascading and two different
regimes presented in multiparticle production. Dynamics of fractal structure
formation is further studied using the chaoticity approach recently proposed.
The distributions of the horizontal factorial moments are considered and a
scaling behavior, referred to as erraticity, of the normalized moments of the
distributions is obtained. The corresponding entropy indices are calculated
indicating chaotic nature of multiparticle production with a specific
self-similar structure.


title: Evolution of Color Exchange in QCD Hard Scattering

abstract:
  In QCD hard scattering cross sections, the color content of the underlying
hard scattering evolves with a factorization scale. This evolution is
controlled by an anomalous dimension matrix, specific to each hard-scattering
reaction. Anomalous dimensions are determined from the renormalization of
products of ordered exponentials of the gauge field, which describe the
coherent radiation of gluons by incoming hadrons and the observed jets or
particles of the final state. The anomalous dimensions depend on the kinematics
of the underlying hard scattering, but are free of collinear singularities. A
number of these matrices are available in the literature. Here, we exhibit
one-loop mixing matrices for the full list of $2 \to 2$ reactions involving
light quarks and gluons. The eight-by-eight anomalous dimension matrix for
gluon-gluon scattering shows a simplified structure in the basis corresponding
to definite color exchange in the $t$-channel.


title:
Non-perturbative Approach to effective chiral Lagrangians and Meson
  Interactions

abstract:
  We develop a coupled channel unitary approach describing the behavior at
higher energies of systems whose low-energy dynamics is given by effective
O(p^2) and O(p^4) chiral Lagrangians. Our free parameters are those of the
O(p^4) Lagrangian. When applied to the meson-meson interaction, it yields a
remarkable agreement with data up to sqrt{s}=1.2 GeV, dynamically generating
the sigma, f_0, a_0,rho and K^* resonances. Further applications are also
proposed.


title: Isotopic splittings and OPE in B -> D semileptonic decays

abstract:
  It is shown that the kinematical difference in the decays B^- -> D^0 \ell
\tilde \nu and B^0 -> D^+ \ell \tilde \nu due to the isotopic mass splittings
of the B and D mesons is compensated in the total decay rate by an appropriate
difference in the lepton spectra.
  Thus there is no effect on the total decay rates in the linear order in the
isotopic mass splittings, as required by the general consideration based on the
operator product expansion. Although phenomenologically the isotopic difference
in the spectra amounts to at most about 1%, in the theoretical aspect this
effect can be viewed as an additional illustration of how the general OPE
results emerge from the properties of exclusive channels.


title:
A Study of the Day - Night Effect for the \SK Detector: III. The Case of
  Transitions into Sterile Neutrino

abstract:
  Using the results of a high precision calculation of the solar neutrino
survival probability for Earth crossing neutrinos in the case of MSW $\nu_e -->
\nu_s$ transition solution of the solar neutrino problem, we derive predictions
for the one-year averaged day-night (D-N) asymmetries in the deformed
recoil-$e^-$ spectrum and in the energy-integrated event rate due to the solar
neutrinos, to be measured with the Super - Kamiokande detector. The asymmetries
are calculated for three event samples, produced by solar $\nu_e$ crossing the
Earth mantle only, the core, and the mantle only + the core (the full night
sample). The effects of the uncertainties in the value of the bulk matter
density and in the chemical composition of the Earth core on the predictions
for the D-N asymmetries are investigated. The dependence of the D - N effect
related observables on the threshold recoil - e- kinetic energy, TeTh, is
studied. It is shown, in particular, that for $\sin^2 2\theta_V \leq 0.030$ the
one year average D-N - asymmetry in the sample of events due to the
core-crossing neutrinos is larger than the asymmetry in the full night sample
typically by a factor $\sim (2 - 4)$. We find, however, that at small mixing
angles $\sin^2 2 \theta_V \ltap 0.014$, the D-N asymmetry in the case of solar
$\nu_e --> \nu_s$ transitions is considerably smaller than if the transitions
were into an active neutrino, $\nu_e --> \nu_{\mu(\tau)}$. In particular, a
precision better than 1% in the measurement of any of the three one year
averaged D-N asymmetries considered by us would be required to test the small
mixing angle nonadiabatic $\nu_e --> \nu_s$ solution at $\sin^2 2\theta_V
~\ltap ~0.01$.


title:
Majoron emitting neutrinoless double beta decay in the electroweak
  chiral gauge extensions

abstract:
  Fundamental mechanisms for Majoron emitting neutrinoless double beta decay in
SU(3)_C x G_W x U(1) models, for electroweak flavor chiral extensions, G_W =
SU(3)_L and SU(4)_L are pointed out. Both kinds of known Majoron emitting
processes, charged Majoron emitting where the massless Nambu-Goldstone boson
itself carries lepton charge, $L=-2$, and the ordinary Majoron emitting where
the boson has a small mass are found possible. PACS numbers: 11.15.Ex,
12.60.Fr, 14.80.Cp


title: Charmed Baryon Strong Coupling Constants in a Light-Front Quark Model

abstract:
  Light-Front quark model spin wave functions are employed to calculate the
three independent couplings g_{\Sigma_c \Lambda_c \pi}, f_{\Lambda_{c1}
\Sigma_c \pi} and f_{\Lambda^{*}_{c1} \Sigma_c \pi} of S-wave to S-wave and
P-wave to S-wave one-pion transitions. It is found that g_{\Sigma_c \Lambda_c
\pi}=6.81 MeV^{-1}, f_{\Lambda_{c1} \Sigma_c \pi}=1.16 and f_{\Lambda^{*}_{c1}
\Sigma_c \pi}=0.96 . 10^{-4} MeV^{-2}. We also predict decay rates for specific
strong transitions of charmed baryons.


title: HQET and Exclusive B Decays

abstract:
  Exclusive semileptonic B decays are discussed. The emphasis is on using
semileptonic decays to determine |V_{ub}| and |V_{cb}|. Recent progress in our
understanding of B semileptonic decays to excited charmed mesons is also
reviewed.


title: B-\bar{B} Mixings and Rare B Decays in the Topflavour Model

abstract:
  We explore the impact of topflavour model to $B-\bar{B}$ mixings and rare
decays of $B$ mesons. By the flavour-changing neutral current interactions of
this model, the $B-\bar{B}$ mixing amplitudes are substantially affected while
it is hard to investigate the effects on rare decays. Violation of the
unitarity of the CKM matrix is also discussed. We find that the bound on
$|V_{td}|$ can be stronger in this model by combining the experimental bound of
the $B-\bar{B}$ mixing and the bound from violated unitarity.


title: New Electroweak Tests for the Topflavour Model

abstract:
  We explore phenomenologies of the topflavour model for the LEP experiment at
$m_{_Z}$ scale. Implications of the model on the $Z$ peak data are studied in
terms of the precision variables $\epsilon_i$'s.


title:
Helicity Amplitudes for ${\cal O}(\alpha_s)$ Production of $W^+ W^-,
  W^\pm Z, Z Z, W^\pm \gamma,$ or $Z \gamma$ Pairs at Hadron Colliders

abstract:
  We present the one-loop QCD corrections to the helicity amplitudes for the
processes $q\qb \to W^+ W^-, Z Z, W^\pm Z, W^\pm \gamma$, or $Z \gamma$,
including the subsequent decay of each massive vector boson into a pair of
leptons. We also give the corresponding tree-level amplitudes with an
additional gluon radiated off the quark line. Together, these amplitudes
provide all the necessary input for the calculation of the next-to-leading
order QCD corrections to the production of any electroweak vector boson pair at
hadron colliders, including the full spin and decay angle correlations.


title: Two--loop integrals in chiral perturbation theory

abstract:
  We consider chiral perturbation theory in the meson sector at order $E^6$. In
the terminology of the external field technique, the two--loop graphs so
generated are of the sunset type. We discuss the evaluation of several of these
in the case where the masses of the particles running in the loops are equal.
In particular, we present integral representations that are suitable for the
evaluation of diagrams in kinematical regions where branch points and cuts are
present.


title: Effects of Screening of the Instantons in Nonperturbative QCD

abstract:
  The gluon fields screening in the stochastic vacuum of gluodynamics is
studied. The effective action is derived for the instanton interacting with
nonperturbative fields. Quantum nonperturbative effects are shown to affect
greatly the shape of instanton. The power asymptotics x^{-2} of the classical
"instanton's profile function" at large distances is replaced due to yhese
effects by Airy function asymptotics x^{-1/4} exp(-const\cdot x^{3/2}).


title:
Pions in Nuclei and Manifestations of Supersymmetry in Neutrinoless
  Double Beta Decay

abstract:
  We examine the pion realization of the short ranged supersymmetric (SUSY)
mechanism of neutrinoless double beta decay. It originates from the R-parity
violating quark-lepton interactions of the SUSY extensions of the standard
model of the electroweak interactions. We argue that pions are dominant SUSY
mediators in neutrinoless double beta decay. The corresponding nuclear matrix
elements for various isotopes are calculated within the proton-neutron
renormalized quasiparticle random phase approximation. We define those isotopes
which are most sensitive to the SUSY signal and outlook the present
experimental situation with the double beta decay searches for the SUSY. Upper
limits on the R-parity violating 1st generation Yukawa coupling are derived
from various double beta decay experiments.


title:
Determination of Lambda_QCD from the measured energy dependence of
  <1-Thrust>

abstract:
  We directly fit the experimentally measured energy dependence of the average
value of 1-Thrust, <1-T>, over the e^+e^- centre-of-mass energy range Q=14 -
172 GeV to the QCD expectation obtained by integrating up the evolution
equation for d<1-T>/dlog Q in terms of <1-T>. We fit for Lambda_QCD,
uncalculated O(alpha_S^3) and higher perturbative corrections parameterized by
the scheme invariant rho_2, and the parameter lambda which characterizes the
magnitude of the leading 1/Q power corrections anticipated for <1-T>. A
3-parameter fit yields Lambda_QCD=245^{+20}_{-17} MeV, rho_2=-16\pm 11 and
lambda=0.27^{+0.12}_{-0.10} GeV, equivalent to alpha_S(M_Z)=0.1194 \pm 0.0014.
In this approach, there is no error associated with the choice of the
renormalization scale mu.


title: Baryogenesis via neutrino oscillations

abstract:
  We propose a new mechanism of leptogenesis in which the asymmetries in lepton
numbers are produced through the CP-violating oscillations of ``sterile''
(electroweak singlet) neutrinos. The asymmetry is communicated from singlet
neutrinos to ordinary leptons through their Yukawa couplings. The lepton
asymmetry is then reprocessed into baryon asymmetry by electroweak sphalerons.
We show that the observed value of baryon asymmetry can be generated in this
way, and the masses of ordinary neutrinos induced by the seesaw mechanism are
in the astrophysically and cosmologically interesting range. Except for singlet
neutrinos, no physics beyond the Standard Model is required.


title:
TEVATRON-HERA Colour-Octet Charmonium Anomaly Versus Higher-Order QCD
  Effects

abstract:
  Approximately taking into account the higher-order effects due to
multiple-gluon initial-state radiation, we extract from the latest Tevatron
data of prompt J/psi hadroproduction the leading colour-octet matrix elements
within the nonrelativistic-QCD (NRQCD) factorization formalism proposed by
Bodwin, Braaten, and Lepage. We find that the matrix elements which describe
the formation of J/psi mesons from colour-octet cc-bar pairs in the
angular-momentum states ^{2S+1}L_J = ^1S_0 and ^3P_J, with J = 0,1,2, which are
responsible for the excess of the predicted cross section of inelastic J/psi
photoproduction over the existing HERA data at high values of the inelasticity
variable z, are significantly reduced. We conclude that it is premature to
proclaim a discrepancy between the Tevatron and HERA measurements of inclusive
J/psi production in the NRQCD framework. We also consider J/psi mesons
originating from the radiative feed down of promptly produced chi_{cJ} mesons.


title: Electroweak Symmetry Breaking and Higgs Physics

abstract:
  An introduction to electroweak symmetry breaking and Higgs physics is
presented for the Standard Model and its supersymmetric extensions. A brief
overview will also be given on strong interactions of the electroweak gauge
bosons in alternative scenarios. In addition to the theoretical basis, the
present experimental status of Higgs physics and implications for future
experiments at the LHC and $e^+e^-$ linear colliders are discussed.


title: Implication of Exact SUSY Gauge Couplings for QCD

abstract:
  The phase structure of SUSY gauge theories can be very different from their
nonsupersymmetric counterparts. Nonetheless, there is interesting information
which might be gleaned from detailed investigation of these theories. In
particular, we study the precise meaning of the strong interaction scale
$\Lambda$. We ask whether one can meaningfully apply naive dimensional analysis
and also ask whether the study of supersymmetric theories can shed light on the
apparent discrepancy between the perturbative scale $\Lambda_{QCD}$ and the
``chiral lagrangian'' scale $\Lambda_\chi$. We show that in N=1 supersymmetric
Yang Mills theory, ``naive dimensional analysis'' seems to work well, with
$\Lambda_\chi$ consistently equal to the scale at which the perturbatively
evolved physical coupling becomes of order $4 \pi$. We turn to N=2 theories to
understand better the effect of instantons in accounting for the QCD
discrepancy between scales. In N=2 supersymmetric SU(2) the instanton
corrections are known to all orders from the Seiberg-Witten solution and give
rise to a finite scale ratio between the scale at which the perturbatively
evolved and ``nonperturbatively evolved'' couplings blow up. Correspondingly,
instanton effects are important even when the associated perturbatively evolved
gauge coupling only gives $\alpha$ of order 1 (rather than $4 \pi$). We compare
the N=2 result to instanton-induced corrections in QCD, evaluated using lattice
data and the instanton liquid model, and find a remarkably similar behavior.


title:
Disrupting the one-loop renormalization group invariant M/alpha in
  supersymmetry

abstract:
  It is well known that in low energy supersymmetry the ratio of the gaugino
mass to the gauge coupling squared, M/alpha, is renormalization group invariant
to one-loop. We present a systematic analysis of the corrections to this ratio,
including standard two-loop corrections from gauge and Yukawa couplings,
corrections due to an additional U(1)' gaugino, threshold corrections,
superoblique corrections, corrections due to extra matter, GUT and Planck scale
corrections, and ``corrections'' from messenger sectors with supersymmetry
breaking communicated via gauge-mediation. We show that many of these effects
induce corrections at the level of a few to tens of percent, but some could
give much larger corrections, drastically disrupting the renormalization group
extrapolation of the ratio to higher scales. Our analysis is essentially
model-independent, and therefore can be used to determine the ambiguities in
extrapolating the ratio in any given model between the weak scale and higher
scales.


title: Supersymmetric U(1) Gauge Field Theory With Massive Gauge Field

abstract:
  A supersymmetric model with U(1) gauge symmetry will be discussed in this
paper. The model has strict U(1) gauge symmetry and supersymmetry
simultaneously. Besides, there is a massive U(1) gauge field contained in the
model.


title: Neutrino masses in the SU(5)xSU(5)' mirror symmetric model

abstract:
  Motivated by the atmospheric and solar neutrino anomalies, we study neutrino
masses in a parity invariant SU(5)xSU(5)' grand unified model. Constraints from
photon-mirror photon kinetic mixing are discussed.


title:
Branching-ratio and CP violation in semi-inclusive flavor-changing top
  decays

abstract:
  Semi-inclusive top decays, $t \to q_i \v$, are examined in the framework of
the standard model, with $q_i = u {\rm or} c$, $\v$ : vector meson formed by
$q_j \qb_j$ ($q_j = d, s, b$). By using a simple model of hadronization, that
is $ 0 \l| \qb_j \gamma^\mu q_j \r| \v = \mv \fv \evj^\mu$, the total branching
ratio is expected to be $\br(\tivj) < ({\l| \vij^\ast \vtj \r|}/{\l| \vtb
\r|})^2 \times O({10}^{-3})$ depends on the size of the coupling constant
$\fv$. On the other hand, the CP asymmetry should be induced only by the
long-distance effects of intermediate state $q_k \qb_k$ ($q_k = d, s, b$) that
subsequent scatters into the vector meson. The analytical results including the
continuum contributions are given with keeping all masses. However, it yields
the CP asymmetry to be small, i.e. $\acp (\tivj) < {\im [(\vij^\ast \vtj)^\ast
(\vik^\ast \vtk)]}/{\l| \vij^\ast \vtj \r|^2} \times O({10}^{-2})$ for an
identified $q_k \qb_k$ intermediate state, and suppressed more again by a
factor of $\sim {({m_b}^2 - {m_s}^2)}/{\mv^2}$ for summing up all of them.
Particularly, $\acp (t \to u \Upsilon) \simeq \pm 1%$, induced by the
intermediate state $d\bar{d}$ or $s\bar{s}$.


title: Axion Cosmology with its Scalar Superpartner

abstract:
  In supersymmetric theories, the Peccei-Quinn symmetry has a complex extension
as a symmetry of the superpotential, so that the scalar potential always has an
almost flat direction, the dilaton. We discuss how coherent oscillation of the
dilaton affects axion cosmology. We stress that the dilaton decay, if its
dominant mode is not into axions, releases large entropy at a late epoch of the
Universe's evolution to dilute axion energy density and the upperbound of the
decay constant is raised up to about $10^{15}$ GeV. The case of the M-theory
axion is also discussed.


title: Aspects of the theory of deep inelastic scattering

abstract:
  The (electromagnetic or weak) current operator responsible for deep inelastic
scattering (DIS) should be local and satisfy the well-known commutation
relations with the representation operators of the Poincare group. The problem
whether these conditions are compatible with the factorization theorem and
operator product expansion is investigated in detail. We argue that the current
operator contains a nontrivial nonperturbative part which contributes to DIS
even in the Bjorken limit. Nevertheless there exists a possibility that many
results of the standard theory remain.


title:
Direct CP violation in semi-inclusive flavor-changing neutral current
  decays in the MSSM without $R-$parity

abstract:
  Semi-inclusive decays, $\hlx$, are studied in the framework of the minimal
supersymmetric standard model without $R-$parity, where $\qh$ ($\ql$) are the
second or third (first or second) generation quarks with the same charge and
$\xi$ is a vector meson formed by $q_j \qb_j$. The study is focused on the
contributions of sfermions with $m_{\sf} < m_{\rm top}$. In this mass region,
CP asymmetries in top decays can be induced by taking into account the
decay-widths of the exchanged-bosons, while in light-quark decays it can be
generated due to the long-distance effects. The contributions of sfermions also
alter the branching-ratios destructively or constructively depend on the phases
of complex couplings of the $R-$parity violation interactions.


title:
Pion-nucleon scattering in chiral perturbation theory I:
  Isospin-symmetric case

abstract:
  We construct the complete effective chiral pion-nucleon Lagrangian to third
order in small momenta based on relativistic chiral perturbation theory. We
then perform the so-called heavy baryon limit and construct all terms
up-to-and-including order $1/m^2$ with fixed and free coefficients. As an
application, we discuss in detail pion-nucleon scattering. In particular, we
show that the $1/m$ expansion of the Born graphs calculated relativistically
can be recovered exactly in the heavy baryon approach without any additional
momentum-dependent wave function renormalization. We fit various empirical
phase shifts for pion laboratory momenta between 50 and 100 MeV. This leads to
a satisfactory description of the phase shifts up to momenta of about 200 MeV.
We also predict the threshold parameters, which turn out to be in good
agreement with the dispersive analysis. In particular, we can sharpen the
prediction for the isovector S-wave scattering length, $0.083 M_\pi^{-1} \leq
a_{0+}^- \leq 0.093 M_\pi^{-1}$. We also consider the subthreshold parameters
and give a short comparison to other calculations of $\pi N$ scattering in
chiral perturbation theory or modifications thereof.


title: Erratum: Jet Cluster Algorithms in $e^+e^-$ Annihilation

abstract:
  We correct an important misprint in the journal version of our earlier work
on "New Jet Cluster Algorithms: Next-to-leading Order QCD...", published in
Nucl. Phys. B 370 (1992) 310, which may have lead to an incorrect
parametrisation of the leading order QCD coefficients for the JADE type jet
cluster algorithms.


title: Study of Multiparticle Spikes in Central 4.5A GeV/c C-Cu Collisions

abstract:
  An analysis of local fluctuations, or spikes, is performed for charged
particles produced in central C-Cu collisions at 4.5 GeV/$c$/nucleon. The
distributions of spike-centers and the maximum density distributions are
investigated for different narrow pseudorapidity windows to search for
multiparticle dynamical correlations. Two peaks over statistical background are
observed in the spike-center distributions with the structure similar to that
expected from the coherent gluon radiation model and recently found in hadronic
interactions. The dynamical contribution to maximum density fluctuations are
obtained to be hidden by statistical correlations, though behavior of the
distributions shows qualitative agreement with that from the one-dimensional
intermittency model. The observed features of the two different approaches,
coherent vs. stochastic, to the formation of the local dynamical fluctuations
are discussed.


title: Right-handed currents in rare exclusive B -> (K, K*) nu bar{nu} decays

abstract:
  The effects of possible right-handed weak hadronic currents in rare exclusive
semileptonic decays B -> (K, K*) nu bar{nu} are investigated using a
lattice-constrained dispersion quark model for the calculation of the relevant
mesonic form factors. The results obtained for the branching ratios and the
missing energy spectra are presented and the sensitivity of various observables
to long-distance physics is investigated. It is shown that the asymmetry of
transversely polarized K*(T) mesons as well as the K / K*(T) production ratio
are only slightly sensitive to long-distance contributions and mostly governed
by the relative strength and phase of right-handed currents. In particular,
within the Standard Model the production of right-handed K*(T) mesons turns out
to be largely suppressed with respect to left-handed ones, thanks to the
smallness of the final to initial meson mass ratio. Therefore, the measurement
of produced right-handed K*(T) mesons in rare B -> K* nu bar{nu} decays offers
a very interesting tool to investigate right-handed weak hadronic currents.


title: Single-bubble Open Inflation: An Overview

abstract:
  The idea that the universe might be open is an old one, and the possibility
of having an open universe arise form inflation is not new either. However, a
concrete realization of a consistent single-bubble open inflation model is
known only recently. There has been great progress in the last two years in the
development of models of inflation consistent with observations in such an open
universe. In this overview I will describe the basic features and the
phenomenological consequences of such models, making emphasis in the
predictions of the CMB temperature anisotropies that differ from ordinary
inflation.


title: Minimal Supersymmetric Scenarios for Spontaneous CP Violation

abstract:
  We study the possibility of spontaneous CP violation (SCPV) at the tree level
in models with an extended Higgs sector. We show that the minimum equations for
the complex phases of the vacuum expectation values (VEVs) have always a
geometrical interpretation in terms of triangles. To illustrate our method we
analyze the minimal supersymmetric (SUSY) model with R-parity violating
couplings and sneutrino VEVs, where there is no SCPV. Then we study SUSY models
with extra Higgs doublets and/or gauge singlets, and find that the simplest
scenario with SCPV must include at least two singlet fields.


title:
b -> s \gamma decay in the two Higgs doublet model with flavor changing
  neutral currents

abstract:
  We study the b --> s\gamma decay including the next to leading QCD
corrections in the two Higgs doublet model with flavor changing neutral
currents at the tree level. We find the constraints to the flavor changing
parameters of the model, using the experimental results on the branching ratio
of B --> X_s \gamma decay, provided by the CLEO Collaboration, the restrictions
coming from the \Delta F=2 (F=K,D,B) mixing and the \rho parameter.


title:
A Simple Charged Higgs Model of Soft CP Violation without Flavor
  Changing Neutral Currents

abstract:
  We propose a model of soft CP violation in which the CP violating mechanism
naturally lies only in the charged Higgs sector. The charged Higgs mechanism
not only accounts for the measured value of the CP-violating parameter
$\epsilon$ but also accommodates the current limits on $\epsilon'/\epsilon$.
Our model naturally prevents tree-level Flavor-Changing Neutral Currents
(FCNCs) of any kind. Unlike the Weinberg-Branco Three-Higgs Doublet Model, the
deviation from the Standard Model rate for $b\to s\gamma$ is small.
Furthermore, leading contributions to the electron (neutron) electric dipole
moment are non-zero beginning at the three (two) loop level. Surprisingly
similar to the Standard Kobayashi-Maskawa Model, our model is of milliweak
character but with seemingly superweak phenomenology.


title: Sparticle Spectrum and Dark Matter in M-Theory

abstract:
  The phenomenological implications of the eleven dimensional limit of
$M$-theory (strongly coupled $E_8\times E_8$) are investigated. In particular
we calculate the supersymmetric spectrum subject to constraints of correct
electroweak symmetry breaking and the requirement that the lighest
supersymmetric particle provides the dark matter of the universe. The $B$-soft
term associated with the generation of a $\mu$ term in the superpotential is
calculated and its phenomenology is discussed.


title: Interplay Between Strong and Weak CP Phases

abstract:
  We discuss the subtle interplay between strong and weak CP phases that has
often been ignored in the literature. We also point out the potentially
important role that it plays in various models.


title: The Decays of Glueballs to two light mesons

abstract:
  We solve the B.S. equation of glueballs under instantaneous approximation.
With the B.S wave function obtained we calculate the decay width of glueballs
to two pseudoscalar mesons, $\Gamma(\pi\pi)$, $\Gamma(kk)$ and
$\Gamma(\eta\eta)$. $\Gamma(\eta\eta^\prime)$ from QCD anomaly is also
estimated.


title:
QCD Corrections to the Masses of the neutral CP-even Higgs Bosons in the
  MSSM

abstract:
  We perform a diagrammatic calculation of the leading two-loop QCD corrections
to the masses of the neutral CP-even Higgs bosons in the Minimal Supersymmetric
Standard Model (MSSM). The results are valid for arbitrary values of the
parameters of the Higgs and scalar top sector of the MSSM. The two-loop
corrections are found to reduce the mass of the lightest Higgs boson
considerably compared to its one-loop value. The numerical results are analyzed
in the GUT favored regions of small and large \tan \beta. Their impact on a
precise prediction for the mass of the lightest Higgs boson is briefly
discussed.


title: A screening mechanism for extra W and Z gauge bosons

abstract:
  We generalize a previous construction of a fermiophobic model to the case of
more than one extra $W$ and $Z$ gauge bosons. We focus in particular on the
existence of screening configurations and their implication on the gauge boson
mass spectrum. One of these configurations allows for the existence of a set of
relatively light new gauge bosons, without violation of the quite restrictive
bounds coming from the $\rho_{\rm NC}$ parameter. The links with Bess and
degenerate Bess models are also discussed. Also the signal given here by this
more traditional gauge extension of the SM could help to disentangle it from
the towers of Kaluza-Klein states over $W$ and $Z$ gauge bosons in extra
dimensions.


title: Systematics of Slepton Production in e+e- and e-e- Collisions

abstract:
  I present the basic formulae for slepton production in e+e- and e-e-
collisions in an especially simple form, using a helicity basis. This
parametrization introduces the useful `neutralino functions' to connect the
neutralino eigenstates to observable cross sections. [to appear in the
proceedings of the 2nd International Workshop on Electron-Electron Interactions
at TeV Energies (e-e-97), Santa Cruz, CA]


title:
Drell-Yan Non-Singlet Spin Cross Sections and Spin Asymmetry to
  $O(\alpha_s^2)$ (II)

abstract:
  We present predictions for the non-singlet Drell-Yan longitudinal spin cross
sections and spin asymmetry, $A_{LL}$, in proton-proton collisions at large
$p_T$ at the RHIC energy of $200\gev$ at next-to-leading order QCD. The higher
order corrections to the non-singlet polarized cross section,
$\sigma_{NS}^{LL}$, are sizeable and similar to those found for the unpolarized
cross section. The non-singlet asymmetry parameter, $A^{NS}_{LL}$, is very
stable against higher order corrections and is a direct measurement of the
non-singlet (i.e. valence) polarized quark distributions within the proton.


title: Emission of Axions in strongly magnetized star

abstract:
  We show that the axion decay constant does not get any correction at any
order by external magnetic fields. On the other hand, in the context of the
Wilsonian effective action under external magnetic fields, the axial currents
get a finite correction. We then calculate the effect of strong magnetic fields
$B>10^{18}G$ on the axion-nucleon coupling and find that if $B\gtrsim
10^{20}~G$ in strongly magnetized neutron and white dwarf stars, the emission
rate of axions is enhanced by several orders of magnitude.


title:
Spin Structure Function g_2(x,Q^2) and Twist-3 Operators in large-N_C
  QCD

abstract:
  It is shown in the framework of the operator product expansion and the
renormalization group method that the twist-3 part of flavour nonsinglet spin
structure function g_2(x,Q^2) obeys a simple Dokshitzer-Gribov-
Lipatov-Altarelli-Parisi (DGLAP) equation in the large N_C limit even in the
case of massive quarks (N_C is the number of colours). There are four different
types of twist-3 operators which contribute to g_2, including
quark-mass-dependent operators and the ones proportional to the equation of
motion. They are not all independent but are constrained by one relation. A new
choice of the independent operator bases leads to a simple form of the
evolution equation for g_2 at large N_C.