title: Dark Matter Predictions With Non-Universal Soft Breaking Masses

abstract:
  The effect of non-universal SUSY soft breaking on predictions of dark matter
detector event rates are surveyed for supergravity models with gravity mediated
soft breaking. For universal soft breaking in the first two generations and
tan(beta)<=20, non-universal effects can be characterized by four parameters
(two for Higgs and two for third generation squarks) in addition to those of
the minimal model (MSGM). These can increase or decrease event rates by a
factor of 10-100 in the domain m_{\chi_1^0}<60 GeV (\chi_1^0= lightest
neutralino) but produce generally small effects at higher masses. The value of
the top mass and b->s+\gamma branching ratio eliminates most of the parameter
space for \mu<0, causing event rates for \mu<0 to be a factor approximately 100
smaller than for mu>0. A correlation between large (small) event rates and
small (large) b-> s+\gamma branching ratio is observed. The effect of future
satellite (MAP and PLANCK) precision determinations of cosmological parameters
on predicted event rates is examined for examples of the \Lambda CDM and \nu
CDM models. It is seen that these could sharpen the event rate predictions and
also restrict the allowed gaugino mass ranges, thus influencing predictions for
accelerator SUSY searches.


title: Two Component Theory of Neutrino Flavor Mixing

abstract:
  Neutrino flavor mixing is discussed in terms of two-component coupled
left-handed flavor fields. This is to take into account the fact that the weak
interaction couples only to left-handed fields. The flavor fields are written
through a rotation matrix, as a linear combination of left-handed free fields.
In order to obtain properly normalized wave functions directly from those free
fields, states of mixed helicity have to be considered. Neutrino flavor
oscillation amplitudes are also derived.


title: Broad Sub-Continuum Resonances and the Case for Finite-Energy Sum-Rules

abstract:
  There is a need to go beyond the narrow resonance approximation for QCD
sum-rule channels which are likely to exhibit sensitivity to broad resonance
structures. We first discuss how the first two Laplace sum rules are altered
when one goes beyond the narrow resonance approximation to include possible
subcontinuum resonances with nonzero widths. We then show that the
corresponding first two finite energy sum rules are insensitive to the widths
of such resonances, provided their peaks are symmetric and entirely below the
continuum threshold. We also discuss the reduced sensitivity of the first two
finite energy sum rules to higher dimensional condensates, and show these sum
rules to be insensitive to dimension > 6 condensates containing at least one
q-bar q pair. We extract the direct single-instanton contribution to the F_1
sum rule for the longitudinal component of the axial-vector correlation
function from the known single-instanton contribution to the lowest Laplace sum
rule for the pseudoscalar channel. Finally, we demonstrate how inclusion of
this instanton contribution to the finite-energy sum rule leads to both a
lighter quark mass and to more phenomenologically reasonable higher-mass
resonance contributions within the pseudoscalar channel.


title:
Solutions of a Dirac hydrogenlike mesons and scalar confinement in low
  orbital angular momentum states

abstract:
  Wavefunctions of a relativistic heavy quark-light quark $(Q,q)$ system
described by a Dirac hamiltonian are analyzed. By assuming that the confinement
potential is a Lorentz scalar (S), the slope of the Isgur-Wise function is
calculated at zero recoil point. The result obtained is $\xi^\prime(1)=-0.93\pm
0.05.$ This means that the solutions are perfectly consistent. If relativistic
corrections in the light quark wave functions are included the result is
$\xi^\prime(1)=-1.01\pm 0.04.$ From heavy-light data this suggest that if
relativistic effects are considered, scalar confinement is reliable in low
orbital angular momentum states.


title:
Algebraic algorithm for next-to-leading order calculations in the
  large-s/small-x regime

abstract:
  We present an algebraic algorithm for analytical calculation of arbitrary
dimensionally regulated massless two-loop forward-scattering diagrams that
constitute the most cumbersome part of next-to-leading order calculations in
the large-s/small-x regime.


title:
Double $Q^2$-rescaling model and the nuclear effect of the parton
  distribution functions

abstract:
  In order to overcome the shortcoming of nonconservation of nuclear momentum
existing in the original $Q^2$-rescaling model(O$Q^2$RM) and avoid introducing
nuclear shadowing factor, we proposed a double $Q^2$-rescaling model(D$Q^2$RM)
for the parton distributions of the bound nucleon. Using the experimental data
of lepton-nucleus deep inelastic scattering(DIS) and the condition of the
nuclear momentum conservation, the $Q^2$-rescaling parameters of various
partons for Sn, Fe, Ca and C nuclei are determined. The rescaling parameters of
valence quark distributions are larger than unity and graduauly increases with
atomic number A, on the contrary, the rescaling parameters of sea quark
distributions and gluon distributions are smaller than unity, and slowly
decreases with A. By using this model, the experimental data of the DIS
process, the nuclear Drell-Yan process and $J/\psi$ photoproduction process are
consistently and quite satisfactorily explained. Key words --- parton
distribution functions, Nuclear effect, Double $Q^2$-rescaling model.


title: DISASTER++ (Version 1.0)

abstract:
  DISASTER++ is a C++ class library for the calculation of (1+1) and
(2+1)-jet-like quantities in deeply inelastic lepton-nucleon scattering for
one-photon exchange in next-to-leading-order QCD perturbation theory. The
calculation is based on the subtraction formalism. The user has access to an
event record such that an arbitrary set of infrared-safe observables can be
calculated in a single run. Compared to other existing universal programs, the
full dependence on the number of flavours and on the renormalization and
factorization scales is made explicit. An interface class providing a simple
interface from C++ to existing FORTRAN programs is available. In a preliminary
study DISASTER++ is compared to two other programs for various bins of the
lepton variables $x_B$ and $y$, where a particular emphasis is put on different
behaviours for $\xi \to 1$ of the parton densities $f(\xi)$. We find good
agreement of DISASTER++ and DISENT (Version 0.1). The comparison of DISASTER++
and MEPJET (Version 2.0) leads to several discrepancies.


title:
Next--to--Leading Order QCD corrections for the $B^0 \bar{B^0}$--mixing
  with an extended Higgs sector

abstract:
  We present a calculation of the B0-B0--mixing including Next--to--Leading
Order (NLO) QCD corrections within the Two Higgs Doublet Model (2HDM). The QCD
corrections at NLO are contained in the factor denoted by eta_2 which modifies
the result obtained at the lowest order of perturbation theory. In the Standard
Model case, we confirm the results for eta_2 obtained by Buras, Jamin and
Weisz. The factor eta_2 is gauge and renormalization prescription invariant and
it does not depend on the infrared behaviour of the theory, which constitutes
an important test of the calculations. The NLO--calculations within the 2HDM
enhance the LO--result up to 18%, which affects the correlation between M_H and
V_{td}.


title:
Vanishing corrections on the intermediate scale and implications for
  unification of forces

abstract:
  In two-step breaking of a class of grand unified theories including SO(10),we
prove a theorem showing that the scale $M_I$ where the Pati-Salam gauge
symmetry with parity breaks down to the standard gauge group,has vanishing
corrections due to all sources emerging from higher scales $ \mu >M_I$ such as
the one-loop and all higher loop effects,the GUT-threshold,gravitational
smearing,and string threshold effects. Implications of such a scale for the
unification of gauge couplings with small Majorana neutrino masses are
discussed.In string inspired SO(10) we show that $M_I \simeq 5\times
10^{12}$,needed for neutrino masses,with the GUT scale $M_U \simeq M_{str}$ can
be realized provided certain particle states in the predicted spectum are
light.


title: The Quark Spin Distributions of the Nucleon

abstract:
  The quark helicity measured in polarized deep inelastic scattering is
different from the quark spin in the rest frame of the nucleon. We point out
that the quark spin distributions $\Delta q_{RF}(x)$ are connected with the
quark helicity distributions $\Delta q(x)$ and the quark transversity
distributions $\delta q(x)$ by an approximate relation: $\Delta q_{RF}(x) +
\Delta q(x)=2 \delta q(x)$. This relation will be useful in order to measure
the rest frame (or quark model) spin distributions of the nucleon once the
quark helicity distributions and quark transversity distributions are
themselves measured. We also calculate the $x$-dependent quark transversity
distributions $\delta q(x)$ and quark spin distributions $\Delta q_{RF}(x)$ in
a light-cone SU(6) quark-spectator model, and present discussions on possible
effect from the sea quark-antiquark pairs.


title: Testing exotic neutrino-neutrino interactions with AGN neutrinos

abstract:
  We propose a test for non-standard neutrino-neutrino interactions by using
ultrahigh energy AGN neutrinos. Such interactions would influence the AGN
neutrino flux due to collisions with cosmic background neutrinos. For typical
AGN neutrinos we obtain an upper limit for the coupling constant $g<6.4\cdot
10^{-3}$ if the mediator is light and $g/(M_X/MeV) <0.013$ if the mediator is
heavy. We compare our results with constraints from other phenomena previously
considered.


title: Hadronic Physics from the Lattice

abstract:
  Topics covered in this review are the lattice gauge theory approach to the
evaluation of non-perturbative hadronic interactions from first principles,
particularly applications to glueballs, inter-quark potentials, the running
coupling constant and hybrid mesons. Also discussed are the limitations of the
quenched approximation.


title: Regge Trajectories For All Flavors

abstract:
  Based on available data for mesonic resonances of light, medium and heavy
flavors, we have performed a global analysis to construct the corresponding
linear Regge trajectories. These have been supplemented by results from various
phenomenological models presented in the literature. A satisfactory formula is
found for the dependence of the intercept and the slope on quark masses. We
find reasonable agreement with data on production of charmed hadrons through
exchange of our charmed trajectories in the space-like region. When applied to
mesons containing the top quark, our results suggest the impossibility of their
formation as evidenced by other independent analyses.


title: Neutrinos: past, present, future

abstract:
  A general overview of neutrino physics is given. The history of the neutrino
starting from Pauli and Fermi is briefly presented. Two-component neutrinos,
the phenomenological V-A theory and the standard model are discussed. The
problem of neutrino masses and mixing is reviewed.


title: QCD relations between structure functions at small x

abstract:
  We present very simple non-integral relations between deep inelastic
structure functions $F_L$, $F_2$ and the gluon distribution at small $x$ based
on perturbative QCD which are useful for the phenomenological analysis of data
at low $x$. As an application we extract the deep inelastic scattering
cross-sections ratio $R= \sigma_L/\sigma_T$ in the range $10^{-4} \leq x \leq
10^{-2}$ from $F_2$ HERA data.


title: Polarized parton distributions and non-leading reggeons

abstract:
  The small $x$ behaviour of polarized parton distributions is related to
non-leading reggeons in the framework of the high-energy effective action.
Double-logarithmic contributions to the reggeon interaction beyond the ones
included in the GLAP equation are encountered in all polarized parton
distributions. The transversity distributions of quarks and gluons behave
similar at small $x$. Contribution to the spin workshop at DESY-Zeuthen,
September 1997.


title: Summary of the Very Large Hadron Collider Physics and Detector Workshop

abstract:
  One of the options for an accelerator beyond the LHC is a hadron collider
with higher energy. Work is going on to explore accelerator technologies that
would make such a machine feasible. This workshop concentrated on the physics
and detector issues associated with a hadron collider with an energy in the
center of mass of the order of 100 to 200 TeV.


title: Double Unresolved Approximations to Multiparton Scattering Amplitudes

abstract:
  We present approximations to tree level multiparton scattering amplitudes
which are appropriate when two partons are unresolved. These approximations are
required for the analytic isolation of infrared singularities of n+2 parton
scattering processes contributing to the next-to-next-to-leading order
corrections to n jet cross sections. In each case the colour ordered matrix
elements factorise and yield a function containing the singular factors
multiplying the n parton amplitudes. When the unresolved particles are not
colour connected, the approximations are simple products of the familar eikonal
and Altarelli-Parisi splitting functions used to describe single unresolved
emission. However, when the unresolved particles are colour connected the
factorisation is more complicated and we introduce new and general functions to
describe the triple collinear and soft/collinear limits in addition to the
known double soft gluon limits of Berends and Giele. As expected the triple
collinear splitting functions obey an N=1 SUSY identity. To illustrate the use
of these double unresolved approximations, we have examined the singular limits
of the tree level matrix elements for e+e- to 5 partons when only three partons
are resolved. When integrated over the unresolved regions of phase space, these
expressions will be of use in evaluating the O(alpha_s^3) corrections to the
three jet rate in electron positron annihilation.


title: Effective QCD coupling and power corrections to photon-photon scattering

abstract:
  The scattering of two off-shell photons is an infrared-safe process in QCD.
For photon virtualities in the range of a few GeV, accessible at LEPII,
power-behaved contributions to the total cross section may become
non-negligible. Based on a dispersion relation for the running coupling, we
discuss these contributions and calculate the coefficients of the leading power
correction for transversely polarized and longitudinally polarized virtual
photons.


title: The Physics of the Ultraviolet Renormalon

abstract:
  We review the physics of the ultraviolet renormalon. This mini-review is
intended to be a sequel to the review by the same authors at the "QCD '96"
conference last year (hep-ph/9610492).


title:
Bounds on the lightest Higgs boson mass with three and four fermion
  generations

abstract:
  We present lower bounds on the Higgs boson mass in the Standard Model with
three and four fermion generations SM(3,4), as well as upper bounds on the
lightest Higgs boson mass in the minimal supersymmetric extension of the SM
with three and four generations MSSM(3,4). Our analysis utilizes the SM(3,4)
renormalization-group-improved one-loop effective potential of the Higgs boson
to find the upper bounds on the Higgs mass in the MSSM(3,4) while the lower
bounds in the SM(3,4) are derived from considerations of vacuum stability. All
the bounds increase as the degenerate fourth generation mass increases,
providing more room in theory space that respects the increasing experimental
lower limit of the Higgs mass.


title:
Primordial Black Hole Formation in a Double Inflation Model in
  Supergravity

abstract:
  It has been recently pointed out that the initial value problem in new
inflation models is naturally solved by supergravity effects if there exists a
pre-inflation before the new inflation. We study this double inflation model in
details and find that density fluctuations on small cosmological scales are
much larger than those on large scales due to peculiar property of the new
inflation. We show that this results in production of primordial black holes
which have $\sim 1 M_{\odot}$ masses in a certain parameter region of the
double inflation model. We stress that these black holes may be identified with
MACHOs observed in the halo of our galaxy.


title:
Damping rate of plasmons and photons in a degenerate nonrelativistic
  plasma

abstract:
  A calculation is presented of the plasmon and photon damping rates in a dense
nonrelativistic plasma at zero temperature, following the resummation program
of Braaten-Pisarski. At small soft momentum $k$, the damping is dominated by $3
\to 2$ scattering processes corresponding to double longitudinal Landau
damping. The dampings are proportional to $(\alpha/v_{F})^{3/2} k^2/m$, where
$v_{F}$ is the Fermi velocity.


title:
The elastic contribution to the Burkhardt -- Cottingham and Generalized
  Gerasimov--Drell-Hearn Sum Rules

abstract:
  The elastic contribution to the first moment of $g_2(x,Q^2)$ is analysed
using a Drell-Yan-West type of relation and is shown to be negative. For a
qualitative estimate the one-loop contributions to the polarized DIS sum rules
in QED are studied. The behaviour of the generalized Gerasimov-Drell-Hearn sum
rule is sensitive to infrared regularization. With a lower threshold for the
gluon virtuality the relation of the generalized GDH sum rule to the
Burkhardt-Cottingham sum rule is studied. We conclude that the elastic part has
to be included for long range interactions but can be consistently discarded
for short range interactions.


title: Comment on ''Cerenkov radiation by neutrinos in a supernova core"

abstract:
  The helicity changing Cerenkov radiation in a supernova core was used earlier
to put a restrictive bound on the neutrino magnetic moment. Subsequently it was
pointed out, that this result was based on a numerical error in the
calculationn of the refractive index of the SN core and using the correct
numbers it was shown that the photons in a SN core do not have a space-like
dispersion relation, so the Cerenkov process would not occur. Here we show that
the earlier estimate of refractive index was based on the thermodynamic formula
for susceptibility which is inapplicable for real photons or plasmons. However
in an ultrarelativistic plasma the plasmon has a space-like branch in the
dispersion relation hence the Cerenkov radiation of a plasmon is kinematically
allowed. We show that the observations of neutrino flux from SN1987A put a
constraint on the neutrino magnetic moment $\mu_{\nu} < 0.6\times
10^{-11}\mu_B$.


title: The N - Jet Inclusive Cross-Section in the Hard Pomeron Model

abstract:
  The inclusive production of several jets is studied in the framework of the
hard pomeron model. The average jet momenta are found to be strongly ordered
and growing towards the central c.m. rapidity, as expected. Strong positive
correlations are found for pairs of jets neighbouring in rapidity, both in the
forward-backward and forward-forward directions.


title: Theoretical and phenomenological aspects of G$\chi$PT

abstract:
  Consequences of the alternative mechanism of spontaneous breaking of chiral
symmetry without formation of a large quark antiquark condensate is reviewed.
Emphasis is put on the resulting picture of light quark masses.


title: Vector Boson Scattering in the Standard Model - an Overview of Formulae

abstract:
  Tree-level scattering amplitudes of longitudinally polarized electroweak
vector bosons in the Standard Model are calculated using Mathematica package
Feyncalc. The modifications of low-energy theorems for longitudinally polarized
W and Z in the Standard Model are discussed.


title:
Gluon polarization from correlated high-pT hadron pairs in polarized
  electro-production

abstract:
  We propose to measure the gluon distribution function Delta G(eta) at eta <
0.2 via pseudo jet production in polarized fixed target lepton nucleon
scattering at typical lepton beam energies of 200 GeV. The measurement of the
spin-asymmetry for the production of correlated charge conjugated hadrons of
opposite transverse momentum can be directly related to Delta G(eta) through
the photo-gluon fusion process. Wa also present a numerical analysis of the
accuracy which can be obtained for different flavors and kinematics of the
observed hadron pair.


title: FCNC top decays into Higgs bosons in the MSSM

abstract:
  We compute the partial width of the FCNC top quark decay t->c h in the
framework of the Minimal Supersymmetric Standard Model, where h = h0, H0, A0 is
any of the neutral Higgs of the MSSM. We include the SUSY electroweak, Higgs,
and SUSY-QCD contributions. Our results substantially improve previous
estimations on the subject, and we find that there is a possibility that they
can be measured at LHC.


title: eta-eta' mixing from U_L(3) x U_R(3) Chiral Perturbation Theory

abstract:
  We obtain explicit expressions for the \eta and \eta' masses and decay
constants using U_L(3) x U_R(3) chiral perturbation theory at next-to-leading
order in a combined expansion in p^2 and 1/Nc. A numerical fit of the
parameters appearing to this order of the expansion is also discussed.


title: Deuteron Disintegration in Quark-Parton Model

abstract:
  The deuteron disintegration process with the emission of fast proton in the
vicinity of the kinematical boundary of the reaction, when Feynman variable
$x\to 2$, is studied. The consideration is fulfilled in the framework of the
quark-parton model of cumulative phenomena based on perturbative QCD
calculations of the corresponding quark diagrams near the thresholds, at which
some quarks ("donors") in the nuclear flucton transfer all their longitudinal
momenta to the distinguished active quarks and become soft. The presence of the
multi-quark $6q$-configuration in a deuteron is essentially exploited in the
consideration. The different versions of hadronization mechanisms of the
produced cumulative quarks into cumulative particles are analyzed. It is shown
that in the case of the production of cumulative protons from deuteron the
hadronization through the coalescence of three cumulative quarks is favorable
and leads to the $(2-x)^5$ cross section threshold behavior whereas the usual
hadronization through one cumulative quark fragmentation into proton the same
as the calculations predicts for the deuteron structure function $F^d_2(x)$ at
$x\to 2$ in DIS processes. The results of the calculations are compared with
the available experimental data.


title: Off-forward quark distributions of the nucleon in the large N_c limit

abstract:
  We study the off-forward quark distributions (OFQD's) in the chiral
quark-soliton model of the nucleon. This model is based on the large-N_c
picture of the nucleon as a soliton of the effective chiral lagrangian and
allows to calculate the leading twist quark- and antiquark distributions at a
low normalization point. We demonstrate the consistency of the approach by
checking various sum rules for the OFQD's. We present numerical estimates of
the isosinglet distribution H(x,\xi,\Delta^2). In contrast to other approaches
we find a strong qualitative dependence on the longitudinal momentum transfer,
\xi. In particular, H(x,\xi,\Delta^2) as a function of x exhibits fast
crossovers at |x| = \xi/2. Such behaviour could lead to a considerable
enhancement of the deeply-virtual Compton scattering cross section.


title:
On the Phase Structure of the 3D SU(2)--Higgs Model and the Electroweak
  Phase Transition

abstract:
  The phase structure of the 3D SU(2)--Higgs model, the dimensionally reduced
effective theory for the electroweak model at finite temperature, is analysed
on the lattice using a variant of the linear $\de$--expansion. We develop a
systematic variational cumulant expansion for general application to the study
of gauge invariant operators in 3D gauge-Higgs models, with emphasis on the
symmetric phase. In particular, the technique is not restricted to finite
lattice volumes, and application to the fundamental 3D SU(2)--Higgs model
allows the discontinuity of certain observables across the first--order
transition to be observed directly for small 4D Higgs masses. The resulting
phase structure agrees well with Monte Carlo simulations for small Higgs
masses, but, at least to the order calculated, the technique is less sensitive
to the expected evolution of the transition to a crossover for Higgs masses
above 80 GeV.


title: Cut Vertices and Semi-Inclusive Deep Inelastic Processes

abstract:
  Cut vertices, a generalization of matrix elements of local operators, are
revisited, and an expansion in terms of minimally subtracted cut vertices is
formulated. An extension of the formalism to deal with semi-inclusive deep
inelastic processes in the target fragmentation region is explicitly
constructed. The problem of factorization is discussed in detail.


title: Cosmological implications of neutrinos

abstract:
  Massive neutrinos were the first proposed, and remain the most natural,
particle candidate for the dark matter. In the absence of firm laboratory
evidence for neutrino mass, considerations of the formation of large scale
structure in the universe provide a sensitive, albeit indirect, probe of this
possibility. Observations of galaxy clustering and large angle anisotropy in
the cosmic microwave background have been interpreted as requiring that
neutrinos provide about 20% of the critical density. However the need for such
`hot' dark matter is removed if the primordial spectrum of density fluctuations
is tilted below scale-invariance, as is often the case in physically realistic
inflationary models. This question will be resolved by forthcoming precision
measurements of microwave background anisotropy on small angular scales. This
data will also improve the nucleosynthesis bound on the number of neutrino
species and test whether decays of relic neutrinos could have ionized the
intergalactic medium.


title: Dynamical Supersymmetry Breaking---Why and How

abstract:
  This theoretical review is intended to give non-theorists a flavor of the
ideas driving the current efforts to experimentally find supersymmetry. We
discuss the main reasons behind the expectation that supersymmetry may be "just
around the corner" and may be discovered in the near future. We use simple
quantum-mechanical examples to illustrate the concept---and the power---of
supersymmetry, the possible ways to break supersymmetry, and the dynamical
generation of small scales. We then describe how this theoretical machinery
helps shape our perception of what physics beyond the electroweak scale might
be.


title:
Inelastic Final-State Interactions and Two-body Hadronic B decays into
  Single-Isospin channels

abstract:
  The role of inelastic final-state interactions in CP asymmetries and
branching ratios is investigated in certain chosen single isospin two-body
hadronic B decays. Treating final-state interactions through Pomeron and Regge
exchanges, we demonstrate that inelastic final state interactions could lead to
sizeable effects on the CP asymmetry.


title: Sneutrino Mixing

abstract:
  In supersymmetric models with nonvanishing Majorana neutrino masses, the
sneutrino and antisneutrino mix. The conditions under which this mixing is
experimentally observable are studied, and mass-splitting of the sneutrino mass
eigenstates and sneutrino oscillation phenomena are analyzed.


title: Status of Light Gaugino Scenarios

abstract:
  I summarize recent devlopments in supersymmetry scenarios which leave some or
all gauginos light. The emphasis is on experimental and phenomenological
progress in the past year.


title:
The Spin Structure of the qq Interaction and the Mass Spectra of Bound
  q\bar q Systems: Different Versions of the 3-Dimensional Reductions of the
  Bethe-Salpeter Equation

abstract:
  Bound q\bar q -systems are considered in the framework of three different
versions of the 3-dimensional reduction of the Bethe-Salpeter equation, all
having the correct one-body limit when one of the constituent quark masses
tends to infinity, and in the framework of the Salpeter equation. The spin
structure of confining qq interaction potential is taken in the form
x\gamma_{1}^{0}\gamma_{2}^{0}+(1-x)I_{1}I_{2}, with 0 \leq x \leq 1. The
problem of existence (nonexistence) of stable solutions of 3-dimensional
relativistic equations for bound q\bar q systems is studied for different
values of x from this interval. Some other aspects of this problem are
discussed.


title: Dimension-six Proton Decays in the Modified Missing Doublet SU(5) Model

abstract:
  Dimension-five operators for nucleon decays are suppressed in the modified
missing doublet (MMD) model in the supersymmetric SU(5) grand unification. We
show that nonrenormalizable interactions decrease the unification scale in the
MMD model which increases the nucleon decay rate of dimension-six operators by
a significant amount. We find that the theoretical lower bound on the proton
life time $\tau(p \to \e^+ \pi^0)$ is within the observable range at
SuperKamiokande.


title:
Simulation of Bose-Einstein effect using space-time aspects of Lund
  string fragmentation model

abstract:
  The experimentally observed enhancement of number of close boson pairs in
e+e- collisions is reproduced by local weighting according to the quantum
mechanical prescriptions for production of identical bosons. The space-time
picture of the process, inherently present in the Lund fragmentation model, is
explicitly used. The model is used to check systematic errors in the W mass
measurements due to the Bose-Einstein effect. The possibility of direct
implementation of the Bose-Einstein effect into string fragmentation is
discussed.


title: Masses, decays and mixings of gluonia in QCD

abstract:
  This is a review of the estimate of the gluonia masses, decay and mixings
from QCD spectral sum rules and low-energy theorems. Some phenomenological
maximal gluonium-quarkonium mixing shemes in the scalar sector are presented.
This talk is a compact version of the work in Ref.[1] (hep-ph/9612457) having
the same title.


title: Reconstruction and approximation effects on W mass distributions at LEP2

abstract:
  We analyze from a theoretical point of view the impact of various
approximations on W mass distributions. This is done both at parton level and
after a simulated W mass reconstruction using constrained fits. The results may
help to understand the origin of various shifts and the broadening of the peak
in direct reconstruction mass measurements.


title: The Two and Three Point One Loop Functions

abstract:
  In the present paper the two and three point functions which occur at the
study of the various physical processes are considered. The investigation has
dan in the framework of the perturbative theory at the one loop level. The
general and asymptotic expressions for these functions are obtained.


title:
Source lifetime dependence of neutrino oscillations - a simple
  wave-function derivation

abstract:
  When neutrinos are produced from long lived particles the life-time of the
source particle affects the flavour conversion probability formula. Due to this
source dependence experiments (like LSND) which use muon decay neutrinos are
two orders of magnitude more sensitive to lower values of mass square
difference compared to other experiments where the sources are pions or kaons.


title: Two body non-leptonic $\Lambda_b$ decays in the large $N_c$ limit

abstract:
  The two body non-leptonic $\Lambda_b$ decays are analyzed in the HQET with
factorization approximation and large $N_c$ limit. In this limit, $\Lambda_b$
and $\Lambda_c$ baryons can be treated as the bound states of chiral soliton
and heavy meson, and consequently the Isgur-Wise function comes out in a
straight forward manner. The results obtained remain well below their
previously predicted upper limit.


title: SUSY-QCD corrections to stop and sbottom decays into W and Z bosons

abstract:
  We calculate the supersymmetric ${\cal O}(\alpha_s)$ QCD corrections to stop
and sbottom decays into vector bosons within the Minimal Supersymmetric
Standard Model. We give analytic formulae and perform a numerical analysis of
these decays. We find that SUSY-QCD corrections to the decay widths are
typically -5% to -10% depending on the squark masses, squark mixing angles, and
the gluino mass.


title:
Probing the helicity structure of $b \to s \gamma$ in $\Lambda_b \to
  \Lambda \gamma$

abstract:
  We investigate the rare decay $\Lambda_b \to \Lambda \gamma$ which receives
both short and long distance contributions. We estimate the long distance
contributions and find them very small. The form factors are obtained from
$\Lambda_c \to \Lambda \ell \bar{\nu}_\ell$ using heavy quark symmetry and a
pole model. The short distance piece opens a window to new physics and we
discuss the sensitivity of $\Lambda_b \to \Lambda \gamma$ to such effects.


title: Light-Cone Quantized QCD and Novel Hadron Phenomenology

abstract:
  I review progress made in solving gauge theories such as collinear quantum
chromodynamics using light-cone Hamiltonian methods. I also show how the
light-cone Fock expansion for hadron wavefunctions can be used to compute
operator matrix elements such as decay amplitudes, form factors, distribution
amplitudes, and structure functions, and how it provides a tool for exploring
novel features of QCD. I also review commensurate scale relations,
leading-twist identities which relate physical observables to each other, thus
eliminating renormalization scale and scheme ambiguities in perturbative QCD
predictions.


title: Neutrino oscillations in a model with a source and detector

abstract:
  We study the oscillations of neutrinos in a model in which the neutrino is
coupled to a localized, idealized source and detector. By varying the spatial
and temporal resolution of the source and detector we are able to model the
full range of source and detector types ranging from coherent to incoherent. We
find that this approach is useful in understanding the interface between the
Quantum Mechanical nature of neutrino oscillations on the one hand and the
production and detection systems on the other hand. This method can easily be
extended to study the oscillations of other particles such as the neutral K and
B mesons. We find that this approach gives a reliable way to treat the various
ambiguities which arise when one examines the oscillations from a wave packet
point of view. We demonstrate that the conventional oscillation formula is
correct in the relativistic limit and that several recent claims of an extra
factor of 2 in the oscillation length are incorrect. We also demonstrate
explicitly that the oscillations of neutrinos which have separated spatially
may be "revived" by a long coherent measurement.


title: Lorentz Symmetry and the Internal Structure of the Nucleon

abstract:
  To investigate the internal structure of the nucleon, it is useful to
introduce quantities that do not transform properly under Lorentz symmetry,
such as the four-momentum of the quarks in the nucleon, the amount of the
nucleon spin contributed by quark spin, etc. In this paper, we discuss to what
extent these quantities do provide Lorentz-invariant descriptions of the
nucleon structure.


title: Comment Concerning Relativistic Corrections in NRQCD

abstract:
  We examine the subtle differences between two possible frameworks for the
calculation of quarkonium production. The differences between the two methods
are not a concern when one calculates only to leading order in the relativistic
expansion, but when relativistic corrections are included, the two formulations
seem at first to be at variance with one another. They can be reconciled
however via a relativistically corrected mass relation relating the boundstate
mass and the quark mass.


title: Formation of Topological Defects

abstract:
  In these lectures, I review cosmological phase transitions and the
topological aspects of spontaneous symmetry breaking. I then discuss the
formation of walls, strings and monopoles during phase transitions including
lattice based studies of defect formation and recent attempts to go beyond the
lattice. The close connection of defect formation with percolation is
described. Open problems and possible future directions are mentioned.


title: Spin Effects In Diffractive Processes at HERA

abstract:
  It is shown that the $A_{ll}$ asymmetry in diffractive $Q \bar Q$
leptoproduction is not small at HERA energies and dependent on the structure of
the pomeron couplings and on the masses of produced quarks. The connection of
this asymmetry with the non-forward gluon distribution in the proton is
discussed.


title: A Spectrometer to Study Elastic and Diffractive Physics at LHC

abstract:
  The possibility to study elastic and diffractive physics in pp collisions at
LHC is investigated. For this purpose we have considered detectors close to the
beam in conjunction with the magnetic elements of the accelerator to provide a
high precision spectrometer for very forward final state protons. The
geometrical acceptance is given and momentum resolution is calculated for
different spatial resolution detectors.


title:
Extending a previous analysis on a possible modulation effect in WIMP
  direct search

abstract:
  In this note we present an extension of our previous analysis of some
preliminary experimental results of the DAMA/NaI Collaboration which might be
indicative of a yearly modulation effect. Here we present a direct way for
obtaining from the experimental data the relevant cosmological implications for
relic neutralinos. We find that some of the configurations singled out by the
DAMA/NaI results would have cosmological properties compatible with a
neutralino as a dominant component of cold dark matter (on the average in the
Universe and in our galactic halo).


title: Gauge Invariance and Factorisation in Exclusive Meson Production

abstract:
  The structure of the nonperturbative vector meson vertex function complicates
the proof of the factorisation theorem for the reaction $\gamma^*p\to Vp$. It
leads to additional contributions but, in a simple model for the vertex
function, gauge invariance ensures that they cancel and factorisation is
preserved.


title: Minimal SU(5) Resuscitated by Higgs Coupling Fixed Points

abstract:
  The issue of gauge unification in the (non-supersymmetric) Standard Model is
reinvestigated. It is found that with just an additional fourth generation of
quarks and leptons, $SU(3) \otimes SU(2) \otimes U(1)$ gauge couplings converge
to a common point $\sim 2.65 \times 10^{15}$ GeV ($\tau_p \sim 10^{34 \pm 1}$
years) provided the Higgs boson has a mass of at least 210 GeV. The presence of
ultraviolet fixed points for the Yukawa and Higgs quartic couplings is found to
be the origin of such unification.


title:
Decay constants in the heavy quark limit in models \`a la Bakamjian and
  Thomas

abstract:
  In quark models \`a la Bakamjian and Thomas, that yield covariance and
Isgur-Wise scaling of form factors in the heavy quark limit, we compute the
decay constants $f^{(n)}$ and $f^{(n)}_{1/2}$ of S-wave and P-wave mesons
composed of heavy and light quarks. Heavy quark limit scaling $\sqrt{M} f =
Cst$ is obtained, and it is shown that this class of models satisfies the sum
rules involving decay constants and Isgur-Wise functions recently formulated by
us in the heavy quark limit of QCD. Moreover, the model also satisfies the
selection rules of the type $f^{(n)}_{3/2} = 0$ that must hold in this limit.
We discuss different Ans\"atze for the dynamics of the mass operator at rest.
For non-relativistic kinetic energies ${p^2 \over 2m}$ the decay constants are
finite even if the potential $V(r)$ has a Coulomb part. For the relativistic
form $\sqrt{p^2 + m^2}$, the S-wave decay constants diverge if there is a
Coulomb singularity. Using phenomenological models of the spectrum with
relativistic kinetic energy and regularized short distance part (Godfrey-Isgur
model or Richardson potential of Colangelo et al.), that yield $\rho^2 \simeq
1$ for the elastic Isgur-Wise function, we compute the decay constants in the
heavy quark limit, and obtain $f_B \simeq$ 300 MeV, of the same order although
slightly smaller than in the static limit of lattice QCD. We find the decay
constants of $D^{**}$ with $j =1/2$ of the same order of magnitude. The
convergence of the heavy quark limit sum rules is also studied.


title: Single W Boson Production in High Energy e-gamma Collisions

abstract:
  We studied single $W$ boson production in high energy $e\gamma$ collisions
and the sensitivity of various observables to the $WW\gamma$ gauge boson
coupling by evaluating the helicity amplitudes of all Feynman diagrams which
contribute to the final state being studied, including the $W$ decay to final
state fermions. We examined $W$ production at 500 GeV and 1 TeV $e^+e^-$
colliders, comparing results for photon spectra obtained from a backscattered
laser and from beamstrahlung radiation. Here we found that the couplings could
best be measured using the backscattered laser photons with
$|\delta\kappa_\gamma|\leq 0.07$ and $|\lambda_\gamma| \leq 0.05$ at a 500 GeV
collider and $|\delta\kappa_\gamma|\leq 0.07$ and $|\lambda_\gamma| \leq 0.02$
at a 1 TeV collider, all at 95% C.L.. The measurement of $\kappa_\gamma$ is at
the threshold of being able to measure loop contributions to the trilinear
gauge boson vertex. For completeness we include the limits achievable using
single $W$ production at a 200 GeV $e^+e^-$ collider in the Weizacker-Williams
approximation. This process can measure $\kappa_\gamma$ to $\pm 0.15$ at 95%
C.L. which is comparable to the $W$ pair production process.


title:
Soffer's inequality and the transversely polarized Drell-Yan process at
  next-to-leading order

abstract:
  We check numerically if Soffer's inequality for quark distributions is
preserved by next-to-leading order QCD evolution. Assuming that the inequality
is saturated at a low hadronic scale we estimate the maximal transverse double
spin asymmetry for Drell-Yan muon pair production to next-to-leading order
accuracy.


title: Sweeping Away the Monopole Problem

abstract:
  We propose a new solution to the cosmological monopole problem in which
domain walls sweep away the magnetic monopoles and subsequently decay. The
solution does not require extensive fine tuning or model building - it works
for the prototype SU(5) Grand Unification model. More generally, it shows that
defect interactions can lead to ``defect erasure'' in phase transitions and
that this can be relevant to early universe physics.


title:
Asymptotic Pade Approximant Predictions: up to Five Loops in QCD and
  SQCD

abstract:
  We use Asymptotic Pade Approximants (APAP's) to predict the four- and
five-loop \beta-functions in QCD and N=1 supersymmetric QCD (SQCD), as well as
the quark mass anomalous dimensions in Abelian and non-Abelian gauge theories.
We show how the accuracy of our previous \beta-function predictions at the
four-loop level may be further improved by using estimators weighted over
negative numbers of flavours (WAPAP's). The accuracy of the improved four-loop
results encourages confidence in the new five-loop \beta-function predictions
that we present. However, the WAPAP approach does not provide improved results
for the anomalous mass dimension, or for Abelian theories.


title: Anomalous Higgs Couplings in Triple Gauge Boson Production at the NLC

abstract:
  We present the sensitivity limits on the coefficients of a dimension-6
effective operators that parametrizes the possible effects of new physics
beyond the Standard Model. Our results are based on the study of the processes
$e^+ e^- \to W^+ W^- \gamma$, $Z Z\gamma$, and $Z\gamma \gamma$ at NLC
energies. In our calculations, we include all the anomalous interactions
involving vector and Higgs bosons, and take into account the Standard Model
irreducible background. We analyse the impact of these new interactions on the
total cross section and on some kinematical distributions of the final state
particles.


title: Rare Radiative B -> tau^+ tau^- gamma Decay

abstract:
  The radiative B -> tau^+ tau^- gamma decay is investigated in the framework
of the Standard Model. When only short (short and long together) distance
contributions are taken into account, the Branching Ratio is found as
9.54x10^(-9) (1.52x10^(-8)), for the value of the cut delta = 0.01 imposed on
the photon energy.


title: Nucleon effects on the photon dispersion relations in matter

abstract:
  We calculate the nucleon contribution to the photon self-energy in a plasma,
including the effect of the anomalous magnetic moment of the nucleons. General
formulas for the transverse and longitudinal components of the self-energy are
obtained and we give explicit results in various limits of physical interest.
The formulas are relevant for the study of the photon dispersion relations and
the dynamical susceptibility in a nuclear medium such as the core of a
supernova, and has implications with regard to the recent suggestion that the
Cerenkov process $\nu \to \nu\gamma$ can take place in such a system.


title: On a Dual Standard Model

abstract:
  I describe various aspects of the construction of a dual standard model
including how it may be possible to obtain the charge spectrum, the family
structure and spin of the known matter particles. I summarize the encouraging
features of the model, the open problems and the predictions indicated at this
stage.


title: |V_{cb}| from semileptonic B decays with two-loop QCD accuracy

abstract:
  Recent progress in calculating O(alpha_s^2) corrections to inclusive and
exclusive semileptonic b-->c transitions is reviewed. The impact of these
corrections on the |V_cb| determination from both inclusive and exclusive B
decays is discussed.


title: Combining real and virtual Higgs boson mass constraints

abstract:
  Within the framework of the standard model we observe that there is a
significant discrepancy between the most precise $Z$ boson decay asymmetry
measurement and the limit from direct searches for Higgs boson production.
Using methods inspired by the Particle Data Group we explore the possible
effect on fits of the Higgs boson mass. In each case the central value and the
95% confidence level upper limit increase significantly relative to the
conventional fit. The results suggest caution in drawing conclusions about the
Higgs boson mass from the existing data.


title:
Asymmetry distributions and mass effects in dijet events at a polarized
  HERA

abstract:
  The asymmetry distributions for several kinematic variables are considered
for finding a systematic way to maximize the signal for the extraction of the
polarized gluon density. The relevance of mass effects for the corresponding
dijet cross section is discussed and the different approximations for including
mass effects are compared. We also compare via the programs Pepsi and Mepjet
two different Monte Carlo (MC) approaches for simulating the expected signal in
the dijet asymmetry at a polarized HERA.


title: Strangeness in Pb-Pb Collisions at 158 A GeV

abstract:
  We study relative strange particle abundances measured in Pb-Pb 158 A GeV
interactions. The thermal and chemical source parameters of these particles are
determined under reaction scenario hypothesis invoking confined and deconfined
hadronic matter.


title: Thermal Flavor Production and Signatures of Deconfinement

abstract:
  Using renormalization group methods we evaluate the thermal strangeness and
charm chemical equilibrium relaxation times in the deconfined quark-gluon
plasma. We present a reaction model and evaluate the total production rate of
strangeness in fixed target Pb-Pb collisions at 10--300 A GeV. We discuss the
relevance of our results to the diagnosis and understanding of the properties
of the deconfined state.


title: Two-loop QCD corrections to charged-Higgs-mediated $b\to s\gamma$ decay

abstract:
  The charged-Higgs-mediated contribution to the Wilson coefficient of the
$b\to s\gamma$ magnetic penguin is expected to be one of the more promising
candidates for a supersymmetric effect in B physics, probably the only one in
gauge-mediated models. We compute the two-loop QCD correction to it. With naive
dimensional regularization and MSbar subtraction, for reasonable values of the
charged Higgs mass and for mu-bar = m_top, we find a (10--20)% reduction of the
corresponding one-loop effect.


title: Decoupling of supersymmetric particles

abstract:
  The possibility of a heavy supersymmetric spectrum at the Minimal
Supersymmetric Standard Model is considered and the decoupling from the low
energy electroweak scale is analyzed in detail. The formal proof of decoupling
of supersymmetric particles from low energy physics is stated in terms of the
effective action for the particles of the Standard Model that results by
integrating out all the sparticles in the limit where their masses are larger
than the electroweak scale. The computation of the effective action for the
standard electroweak gauge bosons W^{+-}, Z and \gamma is performed by
integrating out all the squarks, sleptons, charginos and neutralinos to
one-loop. The Higgs sector is not considered in this paper. The large sparticle
masses limit is also analyzed in detail. Explicit analytical formulae for the
two-point functions of the electroweak gauge bosons to be valid in that limit
are presented. Finally, the decoupling of sparticles in the S, T and U
parameters is studied analitically. A discussion on how the decoupling takes
place in terms of both the physical sparticle masses and the non-physical mass
parameters as the \mu-parameter and the soft-breaking parameters is included.


title:
Mu Problem and Hybrid Inflation in Supersymmetric SU(2)_L x SU(2)_R x
  U(1)_B-L

abstract:
  We present a solution of the mu problem within a supersymmetric model based
on the SU(2)_L x SU(2)_R x U(1)_{B-L} gauge group. We show that this solution
implies a built-in hybrid inflationary scenario, which may result in a
successful baryogenesis via leptogenesis. Baryon number is essentially
conserved as a result of an R-symmetry. Neutrinos with mass in the eV range can
provide the `hot' dark matter component.


title: Neutrino Oscillations from Strings and Other Funny Things

abstract:
  I will discuss three related unconventional ways to generate neutrino
oscillations (1)Equivalence principle violation by the string dilaton field
(i2)Violation of Lorentz Invariance and (3) Equivalence principle violation
through a non-universal tensor neutrino-gravity coupling. These unorthodox
neutrino oscillation mechanisms are shown to be viable at the level of our
present experimental knowledge and demonstrate that neutrino oscillations can
probe very profound questions.


title:
Analytic Perturbation Theory: A New Approach to the Analytic
  Continuation of the Strong Coupling Constant $\alpha_S$ into the Timelike
  Region

abstract:
  The renormalization group applied to perturbation theory is ordinarily used
to define the running coupling constant in the spacelike region. However, to
describe processes with timelike momenta transfers, it is important to have a
self-consistent determination of the running coupling constant in the timelike
region. The technique called analytic perturbation theory (APT) allows a
consistent determination of this running coupling constant. The results are
found to disagree significantly with those obtained in the standard
perturbative approach. Comparison between the standard approach and APT is
carried out to two loops, and threshold matching in APT is applied in the
timelike region.


title: Scalar sigma meson via chiral and crossing dynamics

abstract:
  We show that the non-strange scalar $\sigma$ meson, as now reported in the
1996 PDG tables, is a natural consequence of crossing symmetry as well as
chiral dynamics for both strong interaction low energy $\pi\pi$ scattering and
also $K \to 2\pi$ weak decays.


title: Supersymmetric Strings and Fermionic Zero Modes

abstract:
  I review recent work concerning the microphysics of cosmic string solutions
of N=1 supersymmetric gauge field theories.


title:
The Systematical Uncertainties in Measurements of the Spin-Dependent
  Structure Function g1n with He-3 Target due to Radiative Correction Procedure

abstract:
  The sources of the systematical uncertainties due to radiative correction
procedure in measurements of the structure function $g_1^n$ with $^3$He target
are considered. Their numerical estimations are presented. The relative
systematical uncertainty does not exceed 5%.


title: Some Phenomenological Properties of the Chiral Transition in QCD

abstract:
  On the basis of the NJL model as an effective theory of QCD and analogies
with condensed matter physics, we extract simple physical pictures of the
chiral phase transition at finite temperature $T$ and/or chemical potential
$\mu$ and predict interesting phenomena associated with the phase transition
which may be seen in relativistic heavy-ion collisions to be performed in RHIC
or LHC. We indicate that the macroscopic equation describing non-equilibrium
phenomena of the chiral transition like DCC might be given by a diffusion-like
equation rather than a wave equation especially when the baryon density is
present.


title:
Charmed Hadron Production in \pi p and Kp Collisions and Leading
  Particle Effect by Constituent Quark-Diquark Cascade Model

abstract:
  We investigate the meson, baryon and anti-baryon productions in \pi p and Kp
collisions in terms of a constituent cascade model which includes charm
flavour. The constituent diquark in an incident baryon has a tendency to get a
large momentum fraction, resulting in considerable difference of subenergies
for particle productions from quark-diquark and quark-antiquark chains in a
meson-baryon collision. As a consequence, the leading particle effects on D
meson productions are expected to be quite different in \pi+ and \pi- beams at
present accelerator energies.


title:
Collective Excitations of Massive Dirac Particles in Hot and Dense
  Medium

abstract:
  The one-loop dispersion equation which defines the collective excitations of
the massive Dirac particles in hot and dense quark-gluon medium is obtained in
the high temperature limit for the case $m<<T$ and solved explicitly for all
$|\q|$ when $\mu=0$. Four well-separated spectrum branches (quasi-particle and
quasi-hole excitations) are found and their behaviors for the small and large
$|\q|$ are investigated. All calculations are performed using the temperature
Green function technique and fixing the Feynman gauge. The gauge dependency of
the spectra found are briefly discussed.


title: Radiative Leptonic B Decays in the Light Front Model

abstract:
  Within the light front framework, we calculate the form factors for
$B\to\gamma$ transitions directly in the entire physical range of momentum
transfer. Using these form factors, we study the radiative decays of $B\to
l\nu_l\gamma$ and $B_{s(d)}\to\nu\bar{\nu}\gamma$. We show that the decay rates
of $B\to l\nu_l\gamma (l=e,\mu)$ and $B\to\nu\bar{\nu}\gamma$ are larger than
that of the corresponding purely leptonic modes. Explicitly, in the standard
model, we find that the branching ratios of $B\to \mu\nu_{\mu}\gamma$ and
$B_s\to\nu\bar{\nu}\gamma$ are $3.7\times 10^{-6}$ and $5.0\times 10^{-8}$, in
contrast with $3\times 10^{-7}$ and 0 for $B\to\mu\nu_{\mu}$ and
$B\to\nu\bar{\nu}$, respectively.


title: Sum-rule for large-$N_c$ QCD and application to heavy quarkonia

abstract:
  We introduce a new sum-rule for large-$N_c$ QCD which relates the density of
heavy quarkonium states, the state-averaged square of the wavefunction at the
origin, and the heavy quark current-current correlator. Focusing on the region
of energy just above perturbative threshold, we calculate the correlator by
incorporating arbitrarily high orders in the QCD coupling $\alpha_s$. We use
the sum-rule to determine the bottomonium potential using experimentally
measured s-wave leptonic widths and compare the result with the potential
obtained by direct calculation from the measured s-wave spectrum. We discuss
the utility of the sum-rule method for accurate determination of the confining
potential.


title: Experimental search for DCCs using Robust Observables

abstract:
  We have analyzed the joint charged particle to photon density correlations in
WA98 experiment at CERN-SPS in order to study the formation of the chirally
disoriented vacuum in Pb + Pb collisions at 158 AGeV. The method of analysis is
based on the event-by-event estimation of a set of robust observables which are
the ratios of normalized bivariate factorial moments corrected for many
efficiency factors. This is found to be a very powerful technique in
identifying, within the limits of the detector resolution, the events with the
localized charged particle to photon density fluctuations.


title: Confinement, Monopoles and Wilsonian Effective Action

abstract:
  An effective low energy action for Yang-Mills theories is proposed, which
invokes an additional auxiliary field $H_{\mu \nu}$ for the field strength
$F_{\mu \nu}$. For a particular relation between the parameters of this action
a gluon propagator with a $1/p^4$ behaviour for $p^2 \to 0$ in the Landau gauge
is obtained. The abelian subsector of this action admits a duality
transformation, where the dual action contains a Goldstone boson $\varphi$ as
the dual of $H_{\mu \nu}$, and corresponds to an abelian Higgs model in the
broken phase describing the condensation of magnetic charges. The Wilsonian
renormalization group equations for the parameters of the original action are
integrated in some approximation, and we find that the relation among the
parameters associated with confinement appears as an infrared attractive fixed
point.


title: Theoretical Interpretations of the HERA High-Q2 Events

abstract:
  Theoretical interpretations of the high-Q^2 events recently observed in
deep-inelastic positron-proton scattering at HERA are reviewed. We discuss
leptoquarks, squarks with R-parity violating couplings, and contact
interactions. Bounds from and implications on other experiments are taken into
consideration.


title:
Low-energy formulas for neutrino masses with $\tan \beta$-dependent
  hierarchy

abstract:
  Using radiative correction and seesaw mechanism,we derive analytic formulas
for neutrino masses in SUSY unified theories exhibiting, for the first time, a
new hierarchial relation among them.The new hierarchy is found to be quite
significant especially for smaller values of $\tan\beta$.


title: D-Term Inflation: The Good, the Bad and the Ugly

abstract:
  An inflationary stage dominated by a D-term avoids the slow-roll problem of
inflation in supergravity and can naturally emerge in theories with a
non-anomalous or anomalous U(1) gauge symmetry. In this talk different aspects
of D-term inflation are discussed.


title:
Single spin asymmetries in $\ell p^\uparrow \to hX$ and $e^-e^+ \to
  q\bar q \to h^\uparrow X$

abstract:
  Spin observables may reveal much deeper properties of non perturbative
hadronic physics than unpolarized quantities. We discuss here possible origins
of single spin asymmetries in DIS, absent in the elementary lepton-quark
interactions, and suggest strategies to isolate and understand some non
perturbative spin dependence of distribution and fragmentation functions. We
also discuss the polarization of hadrons produced in $e^+e^-$ annihilation at
LEP and show how final state $\qq$ 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 $K^{*0}, \phi$ and $D^*$ in
agreement with recent OPAL data. Possible analogous effects in DIS and other
processes are suggested.


title:
Towards Extractions of the CKM Angle $\gamma$ from $B_{u,d}\to\pi K$ and
  Untagged $B_s\to K\bar{K}$ Decays

abstract:
  The decays $B_d\to\pi^\mp K^\pm$ and $B^\pm\to\pi^\pm K$ provide interesting
constraints on the angle $\gamma$ of the unitarity triangle of the CKM matrix.
It is shown that bounds on $\gamma$ can also be obtained from the time
evolution of untagged $B_s\to K^+K^-$ and $B_s\to K^0\bar{K^0}$ decays,
provided the $B_s$ system exhibits a sizeable width difference
$\Delta\Gamma_s$. A detailed discussion of rescattering processes and
electroweak penguin effects, which limit the theoretical accuracy of these
constraints, and of methods to control them through experimental data is given.
Moreover, strategies are pointed out to go beyond these bounds by relating the
$B_{u,d}\to\pi K$ and untagged $B_s\to K\bar{K}$ decays through the SU(3)
flavour symmetry of strong interactions. If a tagged, time-dependent
measurement of the $B_s\to K^+K^-$ and $B_s\to K^0\bar{K^0}$ modes should
become possible, $\gamma$ could be determined from the corresponding
observables in a way that makes use of only the SU(2) isospin symmetry and
takes into account rescattering effects ``automatically''. The impact of
new-physics contributions to $B^0_s - \bar{B^0_s}$ mixing is also analysed, and
interesting features arising in such a scenario of physics beyond the Standard
Model are pointed out.


title: Quantum Effects on Higgs Winding Configurations

abstract:
  We examine the quantum corrections to the static energy for Higgs winding
configurations. We evaluate the effective action for such configurations in
Weinberg-Salam theory without U(1)-gauge fields or fermions. For a
configuration whose size is much smaller than the inverse W-mass, quantum
contributions to the energy are comparable to the classical energy. Moreover,
it is insufficient to consider only one-loop corrections, even as hbar --> 0.
Indeed, all loop orders contribute equally to the static energy. Nevertheless,
quantum fluctuations do not stabilize winding configurations.


title:
Infrared Safe but Infinite: Soft-Gluon Divergences Inside the Physical
  Region

abstract:
  We show that QCD observables defined as infrared- and collinear-safe,
according to the usual Sterman-Weinberg criteria, can nevertheless be infinite
at accessible points inside phase space, to any finite order of perturbation
theory. Infrared finiteness is restored after resummation of divergent terms to
all orders. The resulting characteristic structure, which we call a Sudakov
shoulder, represents an interesting new class of QCD predictions.


title: Transverse and Longitudinal Bose-Einstein Correlations

abstract:
  We show how a difference in the correlation length longitudinally and
transversely, with respect to the jet axis in e+e- annihilation, arises
naturally in a model for Bose-Einstein correlations based on the Lund string
model. In genuine three-particle correlations the difference is even more
apparent and they provide therefore a good probe for the longitudinal
stretching of the string field. The correlation length between pion pairs is
found to be rather independent of the pion multiplicity and the kaon content of
the final state.


title:
Next-to-Leading QCD Corrections to B -> X_s gamma: Standard Model and
  Two-Higgs Doublet Model

abstract:
  We present the QCD corrections to the matching conditions of the Delta B =1
magnetic and chromo-magnetic operators in the Standard Model and in two-Higgs
doublet models. We use an off-shell matching procedure which allows us to
perform the computation using Taylor series in the external momenta, instead of
asymptotic expansions. In the Standard Model case, we confirm previous results
derived on-shell and we obtain BR(B -> X_s gamma)=(3.62\pm 0.33) 10^{-4}. In
the case of the usual two-Higgs doublet model, we show that going from the
leading to the next-to-leading order result improves the CLEO bound on the
charged-Higgs mass from 260 GeV to 380 GeV. This limit is very sensitive to the
definition of errors and we carefully discuss the theoretical uncertainties.
Finally, in the case of the two-Higgs doublet model in which both up- and
down-type quarks couple to the same Higgs field, the theoretical prediction for
BR(B -> X_s gamma) can be reduced by at most 20% with respect to the Standard
Model value.


title:
Next-To-Leading-Order Matching for the Magnetic Photon-Penguin Operator
  in the $B \to X_s \gamma$ Decay

abstract:
  The initial condition at the matching scale $\mu_W = O(M_W)$ for the Wilson
coefficient of the magnetic photon-penguin operator in the decay $B\to X_s
\gamma$ is calculated in the next-to-leading-order approximation. The technical
details of the necessary two-loop calculation in the full theory are described
and the matching with the corresponding result in the effective theory is
discussed in detail. Our outcome for the initial condition confirms the final
results of Adel and Yao and Greub and Hurth. We show that --- contrary to the
claims in the second of these papers --- the matching procedure can be properly
performed for infrared divergent amplitudes, i.e. independently of
contributions from gluon bremsstrahlung.


title: Galactic Halo Models and Particle Dark-Matter Detection

abstract:
  Rates for detection of weakly-interacting massive-particle (WIMP) dark matter
are usually carried out assuming the Milky Way halo is an isothermal sphere.
However, it is possible that our halo is not precisely spherical; it may have
some bulk rotation; and the radial profile may differ from that of an
isothermal sphere. In this paper, we calculate detection rates in
observationally consistent alternative halo models that produce the same halo
contributions to the local and asymptotic rotation speeds to investigate the
effects of theoretical uncertainty of the WIMP spatial and velocity
distribution. We use self-consistent models to take into account the effects of
various mass distributions on the local velocity distribution. The local halo
density may be increased up to a factor of 2 by flattening or by an alternative
radial profile (which may also decrease the density slightly). However, changes
in the WIMP velocity distribution in these models produce only negligible
changes in the WIMP detection rate. Reasonable bulk rotations lead to only an
$O(10%)$ effect on event rates. We also show how the nuclear recoil spectrum in
a direct-detection experiment could provide information on the shape and
rotation of the halo.


title: Hadronic and Electromagnetic Interactions of Quarkonia

abstract:
  We examine the hadronic interactions of quarkonia, focusing on the decays
psi(2s)->psi pi pi and upsilon(2s)-> upsilon pi pi. The leading gluonic
operators in the multipole expansion are matched onto the chiral lagrangian
with the coefficients fit to available data, both at tree-level and loop-level
in the chiral expansion. A comparison is made with naive expectations loosely
based on the large-$N_c$ limit of QCD in an effort to determine the reliability
of this limit for other observables, such as the binding of $\ps$ to nuclei.
Crossing symmetry is used to estimate the cross-section for inelastic
$\pi\ps\to\pi\pss$ scattering, potentially relevant for heavy ion collisions.
The radiative decays psi(2s)->psi pi pi gamma and upsilon(2s)-> upsilon pi pi
gamma are determined at tree-level in the chiral lagrangian. Measurement of
such decays will provide a test of the multipole and chiral expansions. We
briefly discuss decays from the upsilon(3s) and also the contribution from
pions to the electromagnetic polarizability of quarkonia.


title: Doubly Charmed Baryon Production in Hadronic Experiments

abstract:
  In the leading order of perturbative QCD one calculates the total and
differential cross-sections for the hadronic production of doubly charmed
baryons $\Xi_{cc}$ and $\Xi_{cc}^*$ in different experiments. The experimental
evaluation of cross-sections for the $J/\Psi +D + \bar D$ production would
allow one to decrease the uncertainty in the determination of cross-sections
for the doubly charmed baryons due to the choice of $\alpha_s$ and $m_c$. One
shows that in the HERA-B and E781 experiments with fixed tagets the suppression
of the $\Xi_{cc}$ and $\Xi_{cc}^*$ production to the yield of $c \bar c$-pairs
is the value of the order of $10^{-6}-10^{-5}$, whereas at the TEVATRON and LHC
colliders it is about $10^{-4}-10^{-3}$. In the E781 experiment the observation
of $\Xi_{cc}$ and $\Xi_{cc}^*$ is practically unpossible. At the HERA-B and
TEVATRON facilities one can expect $10^5$ events with the double charm, and at
LHC one has about $10^9$ ones.


title: Hadronic Signatures of Deconfinement in relativistic nuclear collisions

abstract:
  We describe the remarkable accomplishments of the current heavy ion Pb--Pb
collision experiments involving strange particle production, carried out at
158A GeV at CERN--SPS. These experimental results, together with the earlier
200A GeV S-induced reactions, imply that, at central rapidity, a novel
mechanism of strangeness production arises, accompanied by excess entropy
formation. We argue that: These results are consistent with the formation of a
space-time localized, highly excited, dense state of matter; The freeze-out
properties of strange hadrons are suggestive of the formation of a
color-deconfined, thermally and nearly chemically equilibrated phase, which
provides at present the only comprehensive framework to describe all
experimental data; The matter fireball is undergoing a transverse expansion
with nearly the velocity of sound of relativistic matter; longitudinal
expansion is not in the scaling regime. We present a first analysis of the
recent Pb-Pb results and discuss several alternative reaction scenarios. We
evaluate quantitatively strangeness production in the deconfined quark-gluon
phase and obtain yields in agreement with the experimental observations made in
200A GeV S--W and 158A GeV Pb-Pb interactions. We also present a qualitative
discussion of J/Psi results consistent with our understanding of strange
particle results.


title: Goldstone Boson Production and Decay

abstract:
  Various topics in and around Goldstone Boson Production and Decay in CHPT are
discussed, in particular I describe some of the progress in $p^6$ Chiral
Perturbation Theory Calculations, the progress in calculating hadronic
contributions to the muon anomalous magnetic moment, here comparing the two
latest results of the light-by-light in some detail. I also present some
progress in various $\eta$ and $K$ decays and their relevance for CHPT.


title: Penguins, Trees and Final State Interactions in B Decays in Broken SU3

abstract:
  The availability of data on $B_s$ decays to strange quasi-two-body final
states, either with or without charmonium opens new possibilities for
understanding different contributions of weak diagrams and in particular the
relative contributions of tree and penguin diagrams. Corresponding $B_d$ and
$B_s$ decays to charge conjugate final states are equal in the SU(3) symmetry
limit and the dominant SU(3) breaking mechanism is given by ratios of CKM
matrix elements. Final State Interactions effects should be small, because
strong interactions conserve $C$ and should tend to cancel in ratios between
charge conjugate states. Particularly interesting implications of decays into
final states containing $\eta$ and $\eta'$ are discussed.


title: Electrically Charged Sphalerons

abstract:
  We investigate the possibility that the Higgs sector of the Weinberg-Salam
model admits the existence of electrically charged, sphaleron states. Evidence
is provided through an asymptotic and numerical perturbative analysis about the
uncharged sphaleron. By introducing a toy model in two dimensions we
demonstrate that such electrically charged, unstable states can exist.
Crucially, they can have a comparable mass to their uncharged counterparts and
so may also play a role in electroweak baryogenesis, by opening up new channels
for baryon number violating processes.


title: On Quark-Hadron Duality in the Heavy Quark Sector

abstract:
  I discuss the issue of quark-hadron duality in the system of heavy-light
quark mesons. As an example, I consider a correlator of two currents comprising
heavy quark operators, and I compare the OPE expression with the result
obtained by a complete insertion of hadronic states. After a smearing
procedure, OPE and hadronic spectral functions agree with each other. However,
the local behaviour of the two functions is different, and the difference
manifests itself in a term which is absent in the OPE.


title:
Parton Distributions from Photoproduction in Polarized ep Scattering at
  HERA

abstract:
  We study photoproduction of jets and single-inclusive hadrons in a polarized
ep collider mode of HERA at sqrt(s)=300 GeV, examining the sensitivity of the
cross sections and their asymmetries to the proton's polarized gluon
distribution and to the completely unknown parton distributions of polarized
photons. We also present for the first time the NLO corrections to the direct
part of polarized single-inclusive hadron photoproduction.


title:
Five-Loop Vacuum Energy Beta Function in phi^4 Theory with
  O(N)-Symmetric and Cubic Interactions

abstract:
  The beta function of the vacuum energy density is analytically computed at
the five-loop level in O(N)-symmetric phi^4 theory, using dimensional
regularization in conjunction with the MSbar scheme. The result for the case of
a cubic anisotropy is also given. It is pointed out how to also obtain the beta
function of the coupling and the gamma function of the mass from vacuum graphs.
This method may be easier than traditional approaches.


title: Non-renormalizable terms and M theory during inflation

abstract:
  Inflation is well known to be difficult in the context of supergravity, if
the potential is dominated by the $F$ term. Non-renormalizable terms
generically give $|V''|\sim V/M^2$, where $V(\phi)$ is the inflaton potential
and $M$ is the scale above which the effective field theory under consideration
is supposed to break down. This is equivalent to $|\eta|\sim (\mpl/M)^2 > 1$
where $\mpl=(8\pi G)^{-1/2}$, but inflation requires $|\eta|<0.1 $. I here
point out that all of the above applies also if the $D$ term dominates, with
the crucial difference that the generic result is now easily avoided by
imposing a discrete symmetry. I also point out that if extra spacetime
dimensions appear well below the Planck scale, as in a recent M-theory model,
one expects $M\ll \mpl$, which makes the problem worse than if $M\sim \mpl$.


title: Indirect CP Violation in the B-System

abstract:
  We show that, contrary to the flavour mixing amplitude q/p, both Re(epsilon)
and Im(epsilon) are observable quantities, where epsilon is the phase-
convention-independent CP mixing. We consider semileptonic B_d decays from a CP
tag and build appropriate time-dependent asymmetries to separate out
Re(epsilon) and Im(epsilon). "Indirect" CP violation would have in
Im(epsilon)/(1+|epsilon|^2) its most prominent manifestation in the B-system,
with expected values in the standard model ranging from -0.37 to -0.18. This
quantity is controlled by a new observable phase: the relative one between the
CP-violating and CP-conserving parts of the effective hamiltonian. For
time-integrated rates we point out a (Delta Gamma)--> (Sigma Gamma)
transmutation which operates in the perturbative CP mixing.


title: Jet observables and energy-momentum tensor

abstract:
  We clarify and extend the theorem of Sveshnikov and Tkachov [hep-ph/9512370],
which gives an explicit connection between jet observables and energy-momentum
tensor. We check the relation between jet observables and energy-momentum
tensor for non-scalar (spinor and vector) field, give a correct treatment of
the light-cone singularity for massless particles, and extend the theorem to
the massless case. We also discuss the issue of gauge invariance.


title: Leptoquarks at Future Lepton Colliders

abstract:
  In this talk I summarize the capability of future lepton colliders to
discover leptoquarks and to determine their electroweak quantum numbers. This
analysis is an updated discussion based on the results presented in the
Snowmass 1996 New Phenomena Working Group report as well as some more recent
work that has appeared in the literature as a result of the HERA high-$Q^2$
excess.


title: Top Quark, W-boson and Light Higgs

abstract:
  In this presentation I will concentrate on top quark physics, the W-boson
mass and the possibility of discovering a light Higgs boson via associated
production at the Fermilab Tevatron.


title: Direct Single Instanton Contributions to Finite Energy Sum Rules

abstract:
  Instanton contributions to pseudoscalar finite-energy sum rules are extracted
from the explicit single-instanton contribution to the pseudoscalar Laplace sum
rule in the instanton liquid model.


title: Relaxing Atomic Parity Violation Constraints on New Physics

abstract:
  The weak charge $Q_W$ measured in atomic parity violation experiments can
receive compensating contributions from more than one new physics source. We
show explicitly that the $\Delta Q_W$ contribution from the exchange of an
extra Z-boson can cancel that from the $s$-channel scalar top or scalar charm
exchange in R-parity violating SUSY models proposed to explain the HERA
high-$Q^2$ anomaly.


title: A Critical Study of B Decays to Light Pseudoscalar

abstract:
  Motivated by the large branching ratios observed for the process
$B\to\eta^{\prime}K$, we examine critically all the ingredients that go into
estimates of B decays into two light pseudoscalars. Within factorization
approximation, we examine several assumptions on the input parameters that
could have a strong bearing on the predictions. Among these are (i) the QCD
scale $\mu$ (ii) value of the form factors (iii) value of the light quark
masses, and in particular $m_s$ (iv) the value $\xi=1/N_c$, (v) charm content
of $\eta^{\prime}$. It is possible to account for all the data without invoking
new physics, though future experiments will provide tighter constraints on the
parameter space. We fin that CP violating asymmetries are in the observable
range for some modes.


title:
Probing New Higgs-Top Interactions at the Tree-Level in a Future e^+e^-
  Collider

abstract:
  The possibility of observing large signatures of new CP-violating and
flavor-changing Higgs-Top couplings in a future e^+e^- collider experiments
such as e^+e^- -> t bar-t h, t bar-t Z and e^+e^- -> t bar-c \nu_e bar-\nu_e, t
bar-c e^+ e^- is discussed. Such, beyond the Standard Model, couplings can
occur already at the tree-level within a class of Two Higgs Doublets Models.
Therefore, an extremely interesting feature of those reactions is that the
CP-violating and flavor-changing effects are governed by tree-level dynamics.
These reactions may therefore serve as unique avenues for searching for new
phenomena associated with Two Higgs Doublets Models and, as is shown here,
could yield statistically significant signals of new physics. We find that the
CP-asymmetries in e^+e^- -> t bar-t h, t bar-t Z can reach tens of percents,
and the flavor changing cross-section of e^+e^- -> t bar-c \nu_e bar-\nu_e is
typically a few fb's, for light Higgs mass around the electroweak scale.


title: Diffractive Exclusive Photon Production in DIS at HERA

abstract:
  We demonstrate that perturbative QCD allows one to calculate the absolute
cross section of diffractive exclusive production of photons at large $Q^2$ at
HERA, while the aligned jet model allows one to estimate the cross section for
intermediate $Q^2 \sim 2 GeV^2$.
  Furthermore, we find that the imaginary part of the amplitude for the
production of real photons is larger than the imaginary part of the
corresponding DIS amplitude by about a factor of 2, leading to the prediction
of a significant counting rate for the current generation of experiments at
HERA. We also find a large azimuthal angle asymmetry in $ep$ scattering for
HERA kinematics which allows one to directly measure the real part of the DVCS
amplitude and hence the nondiagonal parton distributions.


title: Renormalons in Electromagnetic Annihilation Decays of Quarkonium

abstract:
  We study the large-order asymptotic behavior of the perturbation series for
short-distance coefficients in the NRQCD factorization formulas for the decays
J/psi --> e^+e^- and eta_c --> gamma gamma. The short-distance coefficients of
the leading matrix elements are calculated to all orders in the large-N_f
limit. We find that there is a universal Borel resummable renormalon associated
with the cancellation of the Coulomb singularity in the short-distance
coefficients. We verify that the ambiguities in the short-distance coefficients
from the first infrared renormalon are canceled by ambiguities in the
nonperturbative NRQCD matrix elements that contribute through relative order
v^2. Our results are used to estimate the coefficients of higher order
radiative corrections in the decay rates for J/psi --> e^+ e^-, eta_c --> gamma
gamma, and J/\psi --> gamma gamma gamma.


title:
Effects of Non-Standard Interactions for the Energy Spectrum of
  Secondary Leptons in e^+e^- --> t t-bar

abstract:
  The process of top-quark pair production followed by semileptonic decays at
future high-energy e^+e^- linear colliders is investigated as a possible test
of physics beyond the Standard Model. Assuming the most general non-standard
forms for gamma t t-bar, Z t t-bar and Wtb couplings, the energy spectrum of
the single lepton l^{+-} and the energy correlation of l^+ and l^- emerging
from the process e^+e^- --> t t-bar --> l^{+-} ... /l^+l^- ... are calculated.
Expected precision of the non-standard-parameter determination is estimated
adopting the recently-proposed optimal method.


title: Domain Walls Out of Equilibrium

abstract:
  We study the non-equilibrium dynamics of domain walls in real time for
$\phi^4$ and Sine Gordon models in 1+1 dimensions in the dilute regime. The
equation of motion for the collective coordinate is obtained by integrating out
the meson excitations around the domain wall to one-loop order. The real-time
non-equilibrium relaxation is studied analytically and numerically to this
order. The constant friction coefficient vanishes but there is dynamical
friction and relaxation caused by off-shell non-Markovian effects. The validity
of a Markovian description is studied in detail. The proper Langevin equation
is obtained to this order, the noise is Gaussian and additive but colored. We
analyze the classical and hard thermal loop contributions to the self-energy
and noise kernels and show that at temperatures larger than the meson mass the
hard contributions are negligible and the finite temperature contribution to
the dynamics is governed by the classical soft modes of the meson bath. The
long time relaxational dynamics is completely dominated by classical Landau
damping resulting in that the corresponding time scales are not set by the
temperature but by the meson mass. The noise correlation function and the
dissipative kernel obey a generalized form of the Fluctuation-Dissipation
relation.


title:
Oscillations of Moments and Structure of Multiplicity Distributions in
  e+e- Annihilation

abstract:
  Starting from the recognized fact that oscillations of moments with rank and
shoulder structure in the multiplicity distribution have the same origin in the
full sample of events in e+e- annihilation, we push our investigation to the
2-jet sample level, and argue in favor of the use of the negative binomial
multiplicity distribution as the building block of multiparticle production in
e+e- annihilation events. It will be shown that this approach leads to definite
predictions for the correlation structure, e.g., that correlations are flavour
independent.


title:
Soft and Semi-Hard Components Structure in Multiparticle Production in
  High Energy Collisions

abstract:
  Superposition of jets of different flavors as well as superposition of jets
of different topologies describe well observed structures (shoulder, H_q
oscillations) in e+e- annihilation. The analysis of similar effects seen in
experimental data in hadron-hadron collision is performed successfully by
superimposing soft and semi-hard contributions at various energies. Negative
Binomial multiplicity distributions are chosen in all examined classes of
collisions as elementary substructures, i.e., as QCD inspired genuine
self-similar fractal processes. Predictions on final particle multiplicity
distributions in hadron-hadron collisions at 14 TeV are discussed.


title: Photons from the Universe - New Frontiers in Astronomy

abstract:
  This century has seen a dramatic increase in observational possibilities of
the physics of the universe. Several of the very recent new developments with
emphasis on the particle physics aspect and in particular Gamma-Gamma
interactions are briefly discussed in this talk.


title:
Secondary Decays in Atmospheric Charm Contributions to the Flux of Muons
  and Muon Neutrinos

abstract:
  We present a calculation of the fluxes of muons and muon neutrinos from the
decays of pions and kaons that are themselves the decay products of charmed
particles produced in the atmosphere by cosmic ray-air collisions. Using the
perturbative cross section for charm production, these lepton fluxes are two to
three orders of magnitude smaller than the fluxes from the decays of pions and
kaons directly produced in cosmic ray-air collisions. Intrinsic charm models do
not significantly alter our conclusions, nor do models with a charm cross
section enhanced in the region above an incident cosmic ray energy of 1 TeV.


title:
Determination of the anomalous dimension of gluonic operators in deep
  inelastic scattering at O(1/N_f)

abstract:
  Using large N_f methods we compute the anomalous dimension of the
predominantly gluonic flavour singlet twist-2 composite operator which arises
in the operator product expansion used in deep inelastic scattering. We obtain
a d-dimensional expression for it which depends on the operator moment n. Its
expansion in powers of epsilon = (4-d)/2 agrees with the explicit exact three
loop MSbar results available for n less than or equal to 8 and allows us to
determine some new information on the explicit n-dependence of the three and
higher order coefficients. In particular the n-dependence of the three loop
anomalous dimension gamma_{gg}(a) is determined in the C_2(G) sector at
O(1/N_f).


title:
Analyzing QCD Sum Rules for Heavy Baryons at Next-to-Leading Order in
  \alpha_S

abstract:
  In this talk I consider QCD sum rules for the ground state heavy baryons to
leading order in $1/m_Q$ and at next-to-leading order in $\alpha_S$ within the
context of Heavy Quark Symmetry. The analysis is done at a fixed scale $\mu=1
GeV$. The evolution behaviour of the residues is determined by the two-loop
anomalous dimension of the heavy baryon currents calculated earlier. I compare
the diagonal, non-diagonal and constituent type QCD sum rules and show that the
diagonal sum rules are the most reliable one. As central values for the bound
state energies I find $m(\Lambda_Q)-m_Q=760 MeV$ and $m(\Sigma_Q)-m_Q=940 MeV$.
The central values for the residues are given by $F(\Lambda_Q)=0.030 GeV^3$ and
$F(\Sigma_Q)=0.038 GeV^3$.


title: Diffraction in Two-Photon Collisions at TESLA

abstract:
  In this article we discuss the possibility to measure diffraction
dissociation in collisions of real and weakly virtual photons at a 500 GeV e+e-
linear collider.


title: The `Proton Spin' Effect - Theoretical Status '97

abstract:
  The theoretical status of the `proton spin' effect is reviewed. The
conventional QCD parton model analysis of polarised DIS is compared with a
complementary approach, the composite operator propagator-vertex (CPV) method,
each of which provides its own insight into the origin of the observed
suppression in the first moment of $g_1^p$. The current status of both
experiment and non-perturbative calculations is summarised. The future role of
semi-inclusive DIS experiments, in both the current and target fragmentation
regions, is described.


title: Trilepton Higgs signal at hadron colliders

abstract:
  Determining the origin of electroweak symmetry breaking will be one of the
primary functions of high energy colliders. We point out that most Higgs boson
searches pursued at hadron colliders require Yukawa interactions either in the
production or the decay of a Higgs boson. We propose a trilepton Higgs boson
search based only upon the gauge interactions of the Higgs. This strategy can
be utilized successfully for the standard model (SM) Higgs boson as well as
non-standard Higgs bosons which break electroweak symmetry but have little to
do with fermion mass generation. The trileptons come from Wh production
followed by Wh -> WWW^(*) -> 3l decays. A SM Higgs trilepton signal would be
difficult to detect at the Tevatron collider: with 100 fb^{-1} of data, only a
$3\sigma$ signal above background can be achieved after cuts if 140 GeV < mh <
175 GeV. Some discrimination of signal over background can be gained by
analyzing the opposite sign dilepton pT distributions. At the LHC with 30 (100)
fb^{-1} a clear discovery above the $5\sigma$ level is possible for a Higgs
mass in the range 140-185 (125-200) GeV. Prospects for a trilepton Higgs
discovery are greatly improved for models with non-standard Higgs sectors where
a Higgs boson couples preferentially to vector bosons rather than to fermions.


title: Deformed Skyrmions

abstract:
  The spherically symmetric hedgehog ansatz used in the description of the
skyrmion is believed to be inadequate for the rotational states such as the
nucleon (I=J=1/2) and the Delta (I=J=3/2) due to centrifugal forces. We study
here a simple alternative: an oblate spheroidal solution which leads to lower
masses for these baryons. As one might expect, the shape of the solution is
flatter as one increases I=J whether the size of the soliton is allowed to
change or not.


title: Nonabelian Debye screening, tsunami waves, and worldline fermions

abstract:
  I give a pedagogical review of the derivation for the effective lagrangian
for nonabelian Debye screening, or hard thermal loops. Following Kelly, Liu,
Lucchesi, and Manuel, I give the simplest derivation possible, using classical
kinetic theory.
  The result is valid not just for a thermal, but for an arbitrary initial
distributions. I use this to study the evolution, at short times, of a gluonic
``tsunami wave''.
  I also suggest how classical kinetic theory may arise at one loop order.
Using the wordline representation of the one loop effective action, I follow
D'Hoker and Gagn\'{e} to replace the Wilson line by an integral over worldline
fermions. A bilinear of these worldline fermions naturally defines a nonabelian
charge, whose equation of motion is Wong's equation.


title:
Unified explanation of the Solar and Atmospheric neutrino Puzzles in a
  minimal supersymmetric SO(10) model

abstract:
  It was recently suggested that in a class of supersymmetric SO(10) models
with Higgs multiplets in 10, and a single $126+\bar{126}$ representations, if
the $\bar{126}$ contributes both to the right handed neutrino masses as well as
to the charged fermion masses, one can have a complete prediction of the
neutrino masses and mixings. It turns out that if one chooses only one 10,
there are no regions in the parameter space where one can have a large
$\nu_{\mu}-\nu_{\tau}$ mixing angle necessary to solve the atmospheric neutrino
deficit while at the same time solving the solar neutrino puzzle via the $\nu_e
\leftrightarrow \nu_{\mu}$ oscillation. We show that this problem can be solved
in a particular class of SO(10) models with a pair of 10 multiplets if we
include the additional left-handed triplet contribution to the light neutrino
mass matrix. This model cannot reproduce the mass and mixing parameters
required to explain the LSND observations neither does it have have a neutrino
hot dark matter.


title:
The Phenomenology of Single Top Quark Production at the Fermilab
  Tevatron

abstract:
  Single top quark production at the Fermilab Tevatron Run II (a p \bar{p}
collider with \sqrt{S} = 2 TeV) proceeds dominantly via two sub-processes, a
t-channel W-gluon fusion process, and an s-channel W^* process. We show that
these two sub-processes have different sensitivities to new physics effects in
the top quark's electro-weak interactions. The W^* process is sensitive to new
heavy charged resonances, such as a W' boson, while the W-gluon fusion process
is more sensitive to modifications to the top's interaction, including
flavor-changing neutral currents involving the top quark. We examine the
implications of these results on our ability to measure V_{tb} with confidence,
and propose a quantity R = \sigma_{Wg} / \sigma_{W^*}, which may be studied in
order to characterize the confidence one may place upon a given measurement of
V_{tb} from single top production.


title: Baryogenesis and the Thermalization Rate of Stop

abstract:
  We take the first steps towards the complete computation of the
thermalization rate of the supersymmetric particles involved in electroweak
baryogenesis by computing the thermalization rate of the right-handed stop from
the imainary part of the two-point Green function. We use improved propagators
including resummation of hard thermal loops. The thermalization rate is
computed at the one-loop level in the high temperature approximation as a
function of $M_{\tilde t_R}(T)$. We also give an estimate for the magnitude of
the two-loop contributions which dominate the rate for small $M_{\tilde
t_R}(T)$. If the stop is non-relativistic with $M_{\tilde t_R}(T)\gg T$,
thermalization takes place by decay and is very fast.


title:
Drell-Yan forward-backward and spin asymmetries for arbitrary vector
  boson production at next-to-leading order

abstract:
  Longitudinally polarized, unpolarized and forward-backward mass differential
cross sections for Drell-Yan lepton-pair production by arbitrary vector bosons
are calculated in next-to-leading order (NLO) QCD. Analytical results are
presented in a form valid for all consistent $n$-dimensional regularization
schemes, with the mass factorization scheme kept general. NLO predictions for
all Drell-Yan type processes ($W^\pm$, $Z$ and $\gamma^*$) at BNL's
relativistic heavy ion collider (RHIC) are made using polarized parton
distributions which fit the recent deep-inelastic scattering data. These are
examined as tools in the determination of the polarized parton distributions
and the unpolarized $\bar{u}/\bar{d}$ ratio. NLO predictions for the
forward-backward lepton asymmetry at Fermilab are made and the precision
determination of $\sin^2 \theta_W$ from future runs is studied. In all the
above, the QCD corrections are found to be significant. An introductory
discussion is given of various theoretical issues, such as allowable
factorization and regularization schemes, and scale dependences.


title:
QCD corrections to $e^+ e^- \to u~\bar d~s~\bar c$ at Lep 2 and the Next
  Linear Collider: CC11 at O(\alpha_s)

abstract:
  QCD one-loop corrections to the full gauge invariant set of electroweak
diagrams describing the hadronic process $e^+ e^- \to u~\bar d~s~\bar c$ are
computed. Four-jet shape variables for $WW$ events are studied at
next-to-leading order and the effects of QCD corrections on the determination
of the $W$--mass in the hadronic channel at Lep 2 and NLC is discussed. We
compare the exact calculation with a ``naive''approach to strong radiative
corrections which has been widely used in the literature.


title: Large-Angle Bhabha Scattering at LEP 1

abstract:
  A critical assessment is given of the theoretical uncertainty in the
predicted cross-sections for large-angle Bhabha scattering at LEP 1, with or
without t-channel subtraction. To this end a detailed comparison is presented
of the results obtained with the programs ALIBABA and TOPAZ0. Differences in
the implementation of the radiative corrections and the effect of missing
higher-order terms are critically discussed.


title: Vacuum Polarization Contribution to Hydrogen and Positronium Energies

abstract:
  Relative order \alpha(Z\alpha)^3 shift of the energy levels induced by the
vacuum polarization is reexamined for a bound system of two particles with
masses m and M. Recent results for hydrogen and for positronium are shown to
contain an error due to the inadequate procedure of the infrared divergence
handling. Numerically, the correction to the ground state energy constitutes
0.647 kHz for hydrogen and 46.7 kHz for positronium.


title: Next to Leading Order Analysis of Semi-Inclusive DIS

abstract:
  We present a combined NLO analysis to data on both inclusive and
semi-inclusive polarized asymmetries. We present also the NLO corrections to
the direct part of the polarized photoproduction of charged hadrons.


title: Radiative Parton Model Analysis of Recent Polarized DIS Data

abstract:
  An updated next-to-leading order (NLO) QCD analysis of the spin asymmetries
A_1^N(x,Q^2) and parton distributions delta f(x,Q^2) in longitudinally
polarized deep-inelastic lepton-nucleon scattering is presented within the
framework of the radiative parton model taking into account recent experimental
results. The theoretical framework and the main features of the radiative
parton model analysis are briefly reviewed. The small-x behaviour of the
polarized structure function g_1^N(x,Q^2) as well as the shape of the polarized
gluon distribution delta g(x,Q^2) are shown to be still hardly constrained by
present fixed target data.


title: Effective Charge of the Higgs Boson

abstract:
  The Higgs-boson lineshape is studied within the pinch technique resummation
formalism. It is shown that any resonant Higgs-boson amplitude contains a
universal part which is gauge independent, renormalization-group invariant,
satisfies the optical and equivalence theorems, and constitutes the natural
extension of the QED effective charge to the case of the Higgs scalar.


title: Recent developments of PEPSI and SPHINX

abstract:
  Recent developments of the two MC-generators SPHINX and PEPSI are discussed.
In SPHINX the process of polarized photo production was included to simulate
the potential of a polarized HERA to measure the photon structure function. In
PEPSI the CC polarized cross sections on tree level have been added together
with the electroweak corrections to simulate their effect on CC signals
proposed for a polarized HERA.


title: Chiral Anomaly and Eta-Eta' Mixing

abstract:
  We determine the $\eta-\eta'$ mixing angle via a procedure relatively
independent of theoretical assumptions by simultaneously fitting $\eta- eta'$
reactions involving the anomaly--$\eta,\eta'\to\gamma\gamma, \pi^+\pi^-\gamma$.
We extract reasonably precise renormalized values of the octet and singlet
pseudoscalar decay constants $F_8,F_0$ as well as the mixing angle $\theta$.