title: Critical Scaling at Zero Virtuality in QCD

abstract:
  We show that at the critical point of chiral random matrix models, novel
scaling laws for the inverse moments of the eigenvalues are expected. We
evaluate explicitly the pertinent microscopic spectral density, and found it in
agreement with numerical calculations. We suggest that similar sum rules are of
relevance to QCD at the critical temperature, and even above if the transition
is amenable to a Landau-Ginzburg description.


title: $e^- e^-$ Collisions Mediated by Composite Neutrinos

abstract:
  The lepton number violating process, $e^- e^- \to W^- W^-$ has been widely
discussed in the Majorana neutrino exchange mechanism. Here, we discuss this
process in a composite neutrino model where excited Majorana neutrinos are
exchanged. We found several qualitatively different features from the neutrino
exchange case: (1) The longitudinally polarized $W$'s are not produced, (2) the
neutrinoless double beta decay does not constrain much and a much larger cross
section is expected, and (3) CP violating phases may be explored because all
excited neutrinos are heavy so that large mixings among them are expected.


title:
Effective Two-loop Thermodynamic Potential with Fermions in the
  real-time formalism of thermal field theory

abstract:
  Within the real-time formalism (RTF) of thermal field theory,we apply the
hard thermal loop (HTL) resummation technique to calculating effective two-loop
thermodynamic potential in quark-gluon plasma (QGP) and its renormalization.
The result with collective effects is obtained, which is valid for an arbitrary
number of quark flavors with masses.


title:
$R$-Parity Violation and Scalar Leptons Production at Lepton- Antilepton
  Colliders

abstract:
  In the framework of models with R-parity violation, scalar neutrinos and
scalar leptons production in the processes $l_i^+l_j^-\to\tilde {\nu}_{k,L}
Z^0$ and $l^+_il^-_j\to \tilde{l}^{\mp}_{k,L}W^{\pm}$ is considered.We also
consider within the Minimal Supersymmetric Standard Model Higgs bosons
production in the processes $\mu^+\mu^-\toH_i^0Z^0$, $\mu^+\mu^-\to
H^{\pm}W^{\mp}$.


title: Hybrid Charmonium Production in B Decays

abstract:
  We study the production of charmonium hybrids in B decays. We use the
operator product expansion and nonrelativistic QCD to organize the various
contributions to this process. We express the decay rate in terms of a few
matrix elements which eventually will be fixed by experimental measurements or
calculated on the lattice. While the Fock state expansion is problematic for
hybrids, in that there is no perturbative large mass limit, the operator
product expansion still provides a model independent framework for
phenomenological calculations of hybrid production and decay. We then use a
simple flux tube model to estimate the branching ratio B -> psi_g + X, where
psi_g is a J^{PC}=0^{+-} hybrid, the large production of which could help
resolve the low charm multiplicity and semileptonic branching ratio observed in
B decays. We also investigate the possible contributions of tensor charmonium
production. We observe that it is unlikely for either effect to be large enough
to play a significant role in resolving these problems.


title:
Determinations of |V_ub| and |V_cb| from measurements of B ->
  X_u,c\ell\nu differential decay rates

abstract:
  Methods are described in the framework of light-cone expansion which allow
one to determine the Cabibbo-Kobayashi-Maskawa matrix elements |V_ub| and
|V_cb| from measurements of the differential decay rates as a function of the
scaling variables in the inclusive semileptonic decays of B mesons. By these
model-independent methods the dominant hadronic uncertainties can be avoided
and the B -> X_u\ell\nu decay can be very efficiently differentiated from the B
-> X_c\ell\nu decay, which may lead to precise determinations of |V_ub| and
|V_cb|.


title: Non-Perturbative effects from orbifold constructions

abstract:
  We indicate how consistent heterotic orbifold compactifications, including
non perturbative information, can be constructed. We first analyse the
situation in six dimensions, N=1, where strong coupling effects, implying the
presence of five branes, are better known. We show that anomaly free models can
be obtained even when usual modular invariance constraints are not satisfied.
The perturbative massless sector can be computed explicitly from the
perturbative mass formula subject to an extra shift in the vacuum energy.
Explicit examples in D=4, N=1 are presented. Generically, examples exhibit non
perturbative transitions leading to gauge enhancement and/or changing the
number of chiral generations.


title: The Soft R'egime in NRQCD

abstract:
  A Lagrangean and a set of Feynman rules are presented for Non-Relativistic
QCD with manifest power counting in the heavy quark velocity $v$. A r\'egime is
identified in which energies and momenta are of order $Mv$. It is neither
identical to the ultrasoft r\'egime corresponding to radiative processes with
energies and momenta of order $Mv^2$, nor to the potential r\'egime with on
shell quarks and gluons providing the Coulomb binding. In this soft r\'egime,
gluons are on shell, and the quark propagator becomes static. Examples show
that it contributes to one- and two-loop corrections of scattering and
production amplitudes near threshold. The results are readily generalised to
any effective field theory with more than one low energy scale.


title: Electroweak radiative corrections to b --> s gamma

abstract:
  Two loop electroweak corrections to b --> s gamma decays are computed.
Fermion and photonic loop effects are found to reduce R = BR(b --> s
gamma)/BR(b --> c e nu) by 8+-2% and lead to the standard model prediction BR(B
--> X_s gamma)=(3.28 +- 0.30)x10^-4 for inclusive B meson decays. Comparison of
R^{theory} =(3.04 +- 0.25)x10^-3(1+0.10rho), where rho is a Wolfenstein CKM
parameter, with the current experimental average R^{exp}=(2.52+-0.52)x10^-3
gives rho=-1.7+-1.9 which is consistent with -0.21<rho<0.27 obtained from other
B and K physics constraints.


title:
Extracting CKM Phases and $B_s - \bar{B}_s$ Mixing Parameters from
  Angular Distributions of Non-Leptonic B Decays

abstract:
  Suggestions for efficiently determining the lifetimes and mass difference of
the light and heavy $B_s$ mesons ($B_s^L, B_s^H$) from $B_s \to J/ \psi \phi,
D_s^{*+}D_s^{*-}$ decays are given. Using appropriate weighting functions for
the angular distributions of the decay products (moment analysis), one can
extract $(\Gamma_H, \Gamma_L, \Delta m)_{B_s}$. Such a moment analysis allows
the determination of the relative magnitudes and phases of the CP-odd and
CP-even decay amplitudes. Efficient determinations of CP-violating effects
occuring in $B_s \to J/\psi \phi, D_s^{*+} D_s^{*-}$ are discussed in the light
of a possible width difference $(\Delta \Gamma)_{B_s}$, and the utility of this
method for $B \to J/\psi K^*, D^{\ast +}_s \bar D^{\ast}$ decays is noted.
Since our approach is very general, it can in principle be applied to all kinds
of angular distributions and allows the determination of all relevant
observables, including fundamental CKM (Cabibbo-Kobayashi-Maskawa) parameters,
as well as tests of various aspects of the factorization hypothesis. Explicit
angular distributions and weighting functions are given, and the general method
that can be used for any angular distribution is indicated.


title:
Resolving a Discrete Ambiguity in the CKM Angle $\beta$ through $B_{u,d}
  \to J/\psi K^\ast$ and $B_s \to J/\psi \phi$ Decays

abstract:
  It is well known that $\sin(2\beta)$, where $\beta$ is one of the angles of
the unitarity triangle of the CKM matrix, can be determined in a theoretically
clean way by measuring mixing-induced CP violation in the decay $B_d \to J/\psi
K_S$. Another clean extraction of this CKM angle is provided by the
time-dependent angular distribution for the decay products of $B_d \to
J/\psi(\to l^+l^-) K^{\ast0}(\to \pi^0 K_S)$, where we have more observables at
our disposal than in the case of $B_d \to J/\psi K_S$, so that in addition to
$\sin(2\beta)$ also $\cos(2\beta)$ can be probed in a direct way. Unfortunately
a sign ambiguity remains in $\cos(2\beta)$. If it could be resolved, a discrete
ambiguity in the extraction of the CKM angle $\beta$ could be resolved as well,
which would allow a more incisive test of the CKM model of CP violation. This
note shows that detailed time-dependent studies of $B_{u,d} \to J/\psi
K^{\ast}$ and $B_s \to J/\psi \phi$ decay processes can determine the sign of
$\cos(2\beta)$, thereby removing the corresponding ambiguity in the extraction
of the CKM angle $\beta$.


title: A Strong Electroweak Phase Transition up to m_H ~ 105 GeV

abstract:
  Non-perturbative lattice simulations have shown that there is no electroweak
phase transition in the Standard Model for the allowed Higgs masses, m_H \gsim
75 GeV. In the Minimal Supersymmetric Standard Model, in contrast, it has been
proposed that the transition should exist and even be strong enough for
baryogenesis up to m_H ~ 105 GeV, provided that the lightest stop mass is in
the range 100...160 GeV. However, this prediction is based on perturbation
theory, and suffers from a noticeable gauge parameter and renormalization scale
dependence. We have performed large-scale lattice Monte Carlo simulations of
the MSSM electroweak phase transition. Extrapolating the results to the
infinite volume and continuum limits, we find that the transition is in fact
stronger than indicated by 2-loop perturbation theory. This guarantees that the
perturbative Higgs mass bound m_H ~ 105 GeV is a conservative one, allows
slightly larger stop masses (up to ~ 165 GeV), and provides a strong motivation
for further studies of MSSM electroweak baryogenesis.


title: Gauge theory of phase and scale

abstract:
  The old Weyl's idea of scale recalibration freedom and the Infeld and van der
Waerden (IW) ideas concerning geometrical interpretation of the natural spinor
phase gauge symmetry are discussed in the context of moderm models of
fundamental particle interactions. It is argued that IW gauge symmetry can be
naturaly identified with U(1) symmetry of Weinberg-Salam model. It is also
argued that there are no serious reasons to reject Weyl's gauge theory from the
considerations. Its inclusion enriches the original Weinberg-Salam theory and
leads to predictions of new phenomena that do not contradict experiments.


title:
Evidence for xi- and t-dependent damping of the Pomeron Flux in the
  proton

abstract:
  We show that a triple-Regge parametrization of inclusive single diffraction
agrees with the data in the following two domains: (a) xi > 0.03 at all t, (b)
|t| > 1 GeV^2 at all xi. Since the triple-Regge parametrization fails when
applied to the full xi-t range of the total single-diffractive cross section,
we conclude that damping occurs only at low-xi and low-|t|. We give a (``toy'')
parametrization of the damping factor, D(xi), valid at low-|t|, which describes
the diffractive differential cross-section (dsig/dt) data at the ISR and
roughly accounts for the observed s-dependence of diffractive total
cross-section up to Tevatron energies. However, an effective damping factor
calculated for the CDF fitted function for dsig/dxidt at sqrt(s} = 1800 GeV and
|t| = 0.05 GeV^2, suggests that, at fixed-xi, damping increases as s increases.
  We conjecture that, in the regions where the triple-Regge formalism describes
the data and there is no evidence of damping, factorization is valid and the
Pomeron-flux-factor may be universal. With the assumption that the observed
damping is due to multi-Pomeron exchange, our results imply that the recent UA8
demonstration that the effective Pomeron trajectory flattens for |t| > 1 GeV$^2
is evidence for the onset of the perturbative 2-gluon pomeron. Our damping
results may also shed some light on the self-consistency of recent measurements
of hard-diffractive jet production cross sections in the UA8, CDF and ZEUS
experiments.


title: Signatures of the light gluino in the top quark production

abstract:
  If a light gluino, with a mass of the order of GeV, exists in the minimal
supersymmetric extension of the Standard Model, then it can contribute to the
production rate of the top quark pairs at hadron colliders via the process
gluino + gluino --> t + tbar. Because the top quark is heavy, the masses of the
superpartners of the left-handed and right-handed top quarks can be very
different such that a parity-violating observable can be induced at the tree
level. We discuss the phenomenology of this parity violating asymmetry at the
CERN Large Hadron Collider.


title: Constraints on background torsion field from K physics

abstract:
  We point out that a background torsion field will produce an effective
potential to the $K$ and $\bar{K}$ with opposite signs. This allows us to
constrain the background torsion field from the $K_L$ and $K_S$ mass
difference, CPT violating $K^\circ$ and $\bar{K^\circ}$ mass difference and the
CP violating quantities $\epsilon$ and $\eta_{+-}$. The most stringent bound on
the cosmological background torsion $< T^0 > < 10^{-25}$ GeV comes from the
direct measurement of the CPT violation.


title: Radial excitations of low--lying baryons and the $Z^+$ penta--quark

abstract:
  Within an extended Skyrme soliton model for baryons the interplay between the
collective radial motion and the SU(3)--flavor--rotations is investigated. The
coupling between these modes is mediated by flavor symmetry breaking.
Collective coordinates which describe the corresponding large amplitude
fluctuations are introduced and treated canonically. When diagonalizing the
resulting Hamiltonian flavor symmetry breaking is fully taken into
consideration. As eigenstates not only the low--lying ${1/2}^+$ and ${3/2}^+$
baryons but also their radial excitations are obtained and compared to the
empirical data. In particular the relevance of radial excitations for the
penta--quark baryon $Z^+$ (Y=2, I=0, $J^\pi={1/2}^+$) is discussed. In this
approach its mass is predicted to be $1.58{\rm GeV}$. Furthermore the widths
for various hadronic decays are estimated which, for example, yields
$\Gamma(Z^+\to NK)\sim 100{\rm MeV}$ for the only permissible decay process of
the $Z^+$.


title: Scale of Leptogenesis

abstract:
  We study the scale at which one can generate the lepton asymmetry of the
universe which could then get converted to a baryon asymmetry during the
electroweak phase transition. We consider the possibility that the Yukawa
couplings are small but sufficiently large to generate enough lepton asymmetry.
This forbids the possibility of the $(B-L)$ breaking scale being the
electroweak scale.


title:
Constraints of mixing angles from neutrino oscillation experiments and
  neutrinoless double beta decay

abstract:
  From the analyses of the recent data of neutrino oscillation experiments
(especially the CHOOZ and the Super KAMIOKANDE experiments), we discuss how
these data affect the neutrinoless double beta decay ($(\beta \beta)_{0\nu}$)
rate and vice versa assuming that neutrinos are Majorana particles. For the
case that $m_1 \sim m_2 \ll m_3$ ($m_i$ are neutrino masses), we obtain, from
the data of the CHOOZ and Super KAMIOKANDE, $0.28 \le \sin^2\theta_{23} \le
0.76$ and $\sin^2\theta_{13} \le 0.05$. Combining the latter constraint with
the analysis of the "averaged" neutrino mass (< m_\nu >) appeared in $(\beta
\beta)_{0\nu}$, we find that (\frac{< m_\nu >-m_2}{m_3-m_2}<\sin^2 \theta_{13}
\le 0.05), which leads to the constraint on (< m_\nu >) as (< m_\nu > \le 0.05
m_3+(1-0.05)m_2). For the case that $m_1 \ll m_2 \sim m_3$, we find that the
data of neutrino oscillation experiments and$(\beta \beta)_{0\nu}$ imply the
constraints of mixing angles.


title:
Renormalon chains contributions to the non-singlet evolutional kernels
  in QCD

abstract:
  Contributions to QCD non-singlet evolution kernels $P(z)$ for the DGLAP
equation and $V(x,y)$ for the Brodsky-Lepage evolution equation are calculated
for a certain class of diagrams which include renormalon chains. Closed
expressions are presented for the sums of these contributions that dominate for
a large number of flavors $N_f \gg 1$. Calculations are performed in covariant
$\xi$-gauge, in the \MSbar scheme. The assumption of "naive nonabelianization"
approximation for kernel calculations is discussed. The partial solution to the
Brodsky-Lepage evolution equation is obtained.


title:
Production of relativistic positronium in collisions of photons and
  electrons with nuclei and atoms

abstract:
  We consider the production of ultrarelativistic positronium (Ps) in $\gamma A
\to Ps + A$ and $e A \to Ps + e A$ processes where $A$ is an atom or a nucleus
with charge $Ze$. For the photoproduction of para- and ortho-Ps and the
electroproduction of para-Ps we obtain the most complete description compared
with previous works. It includes high order $Z \alpha$ corrections and
polarization effects. The accuracy of the obtained cross sections is determined
by omitted terms of the order of the inverse Ps Lorentz factor squared. The
studied high order multi-photon electroproduction of ortho-Ps dominates for the
collision of electrons with heavy atoms over the bremsstrahlung production from
the electron via a virtual photon proposed by Holvik and Olsen. Our results
complete and correct the studies of those authors.


title: Bosonic decays of stop_2 and sbottom_2

abstract:
  We perform a detailed study of the decays of the heavier top and bottom
squarks (stop_2 and sbottom_2) in the Minimal Supersymmetric Standard Model
(MSSM). We show that the decays into Higgs or gauge bosons can be dominant in a
wide range of the model parameters due to the large Yukawa couplings and
mixings of stops and sbottoms. Compared to the conventional decays into
fermions these bosonic decay modes can have significantly different decay
structures and distributions. This could have an important impact on the search
for stop_2 and sbottom_2 and the determination of the MSSM parameters at future
colliders.


title:
Top quark production near threshold: on resummation of O(
  (\beta_0\alpha_s)^n) QCD corrections

abstract:
  We discuss the resummation of the potentially large O((\beta_0\alpha_s)^n)
QCD corrections to the total cross section of the process e^+e^- \to t \bar t
near the threshold. In this approximation, the cross section factorization into
the short- and long-distance parts is valid. The short-distance correction is
reduced to the production vertex renormalization. It amounts to -9.5% and is
well under control. The long distance corrections are accounted for as the
effect of the coupling's running in the QCD potential. We argue that the
accuracy of present predictions for the cross section in the scheme with the
running QCD coupling is about 10%.


title:
A parametrization of the CKM mixing matrix from a scheme of S3L x S3R
  symmetry breaking

abstract:
  Recent interest in flavour or horizontal symmetry building (mass textures)
has been spurred mainly by the large top mass and, hence, the strong hierarchy
in quark masses. Recently, various symmetry breaking schemes have been proposed
based on the discrete, non-Abelian group S3L x S3R, which is broken according
to S3L x S3R > S3_diag > S2_diag. The group S3 treats three objects
symmetrically, while the hierarchical nature of the Yukawa matrices is a
consequence of the representation structure, 1 + 2, of S3, which treats the
generations differently. Different ansaetze for the breaking of the sub-nuclear
democracy give different Hermitian mass matrices, M, of the same modified
Fritzsch type which differ in the numerical value of the ratio M_23/M_22. A fit
to the experimentally determined absolute values of the elements of the CKM
matrix gives bounds on the possible values of the CP violating phase and gives
a clear indication on the preferred symmetry breaking scheme. A parametrization
of the CKM mixing matrix in terms of four quark mass ratios and one CP
violating phase in very good agreement with the absolute value of the
experimentally determined values of the CKM matrix elements is obtained.


title:
CP Violation in the Cabbibo-suppressed Decay Tau->K Pi Nu_tau with
  Polarized Tau Leptons

abstract:
  CP violation from physics beyond the Standard Model (SM) is investigated in
the Cabbibo-suppressed decay $\tau\to K\pi\nu_{\tau}$ with polarized $\tau$
leptons, to which both the ${\rm J}^{P}=1^-$ resonance $K^*$ and the $
J^{P}=0^+$ resonance $K^*_0$ contribute. In addition to the CP-odd rate
asymmetry, $\tau$ polarization enables us to construct three additional CP-odd
polarization asymmetries that can be enhanced due to the interference between
the $K^*$ and $K^*_0$, and whose magnitudes depend crucially on the $K^*_0$
decay constant, $f_{K^*_0}$. Taking a QCD sum rule estimate of $f_{K^*_0}=45$
MeV and the present experimental constraints on the CP-odd parameters into
account, we estimate quantitatively the maximally-allowed values for the CP-odd
rate and polarization asymmetries in the multi-Higgs-doublet (MHD) model and
the scalar-leptoquark (SLQ) models consistent with the SM gauge symmetry where
neutrinos are massless and left-handed as in the SM. We find that the CP-odd
rate and polarization asymmetries are of a similar size for highly-polarized
$\tau$ leptons and, for their maximally-allowed values, CP violation in the MHD
model and two SLQ models may be detected with about $10^6$ and $10^7$ $\tau$'s
at the $1\sigma$ level.


title: The RNO framework to the $\sigma$-particle mass

abstract:
  The "standard" iso-singlet scalar particle $\sigma$ is reconsidered in the
reduced normal-ordering (RNO) framework to the effective SU(2) theory. Recent
reanalysis of the $\pi\pi$-phase shift [1] is used.


title: Total Widths And Slopes From Complex Regge Trajectories

abstract:
  Maximally complex Regge trajectories are introduced for which both Re
$\alpha(s)$ and Im $\alpha(s)$ grow as $s^{1-\epsilon}$ ($\epsilon$ small and
positive). Our expression reduces to the standard real linear form as the
imaginary part (proportional to $\epsilon$) goes to zero. A scaling formula for
the total widths emerges: $\Gamma_{TOT}/M\to$ constant for large M, in very
good agreement with data for mesons and baryons. The unitarity corrections also
enhance the space-like slopes from their time-like values, thereby resolving an
old problem with the $\rho$ trajectory in $\pi N$ charge exchange. Finally, the
unitarily enhanced intercept, $\alpha_{\rho}\approx 0.525$, \nolinebreak is in
good accord with the Donnachie-Landshoff total cross section analysis.


title:
Reanalysis of the Das et al. sum rule and application to chiral $O(p^4)$
  parameters

abstract:
  A sum rule due to Das et al. is reanalyzed using a euclidian space approach
and a Pad\'e resummation procedure. It is shown that the result is essentially
determined by the matrix elements of dimension six and dimension eight
operators which have recently been measured by the ALEPH collaboration. The
result is further improved by using the vector spectral function which must be
extrapolated to the chiral limit. This extrapolation is shown to be reliably
performed under the constraint of a set of sum rules. The sum rule is employed
not as an approximation to $M_{\pi^+}-M_{\pi^0}$ but as an exact result for a
chiral low-energy parameter. A sufficiently precise evaluation provides also an
estimate for a combination of subleading electromagnetic low-energy parameters.


title: Arithmetic and the standard electroweak theory

abstract:
  We propose the relations 1/e - e =3 and tan(2theta_W)=3/2, where e is the
positron charge and theta_W is the weak angle. Present experimental data
support these relations to a very high accuracy. We suggest that some duality
relates the weak isospin and hypercharge gauge groups of the standard
electroweak theory.


title: Evidence for a scalar kappa(900) resonance in pi-K scattering

abstract:
  Motivated by the $1/N_c$ expansion, we study a simple model in which the pi-K
scattering amplitude is the sum of a current-algebra contact term and resonance
pole exchanges. This phenomenological model is crossing symmetric and, when a
putative light strange scalar meson, kappa, is included, satisfies the
unitarity bounds to well above 1 GeV. The model also features chiral dynamics,
vector meson dominance and appropriate interference between the established
scalar K*(1430) resonance and its predicted background. We briefly discuss the
physical significance of the results and directions for further work.


title: Two-loop heavy top corrections to the b --> s gamma decay

abstract:
  We compute the two-loop corrections to the coefficient of the b --> s gamma
magnetic penguin present in the limits of heavy top and/or heavy higgs. This
kind of corrections affects in a significant way the observables measured at
LEP. On the contrary we find that, due to a numerical accident, the correction
to BR(B --> X_s gamma) is negligible (below the 1% level for any possible value
of the higgs mass) when the leading order result is expressed in the usual way
in terms of the semileptonic BR(B --> X_c \bar{e}\nu).


title: Heavy quark expansion in beauty and its decays

abstract:
  I give an introduction to the QCD-based theory of the heavy flavor hadrons
and their weak decays. Trying to remain at the next-to-elementary level and
skip technicalities, I concentrate on the qualitative description of the most
important applications and physical meaning of the theoretical statements. The
numerical results of the dedicated theoretical analyses of extracting V_cb are
given and the possibilities to determine V_ub in future are discussed. At the
same time I describe in simple language subtle peculiarities distinguishing
actual QCD of heavy quarks from naive quantum mechanical treatment often
applied to heavy flavor hadrons. These subtleties are often mistreated.
Particular attention is paid to the concept of the heavy quark mass and its
evaluation, to the kinetic operator and the question of the 1/m_Q corrections
to inclusive widths of heavy flavor hadrons. I argue that the properly defined
b quark mass is known with a good accuracy from the \bar{b} b threshold cross
section.


title:
Renormalization of Schr\"odinger Equation and Wave Functional for
  Rapidly Oscillating Fields in QCD

abstract:
  Background field method is used to perform renormalization group
transformations for Schr\"odinger equation in QCD. The dependence of the ground
state wave functional on rapidly oscillating fields is found.


title:
Phenomenology of light remnant doubly charged Higgs fields in the
  supersymmetric left-right model

abstract:
  It has recently shown that in supersymmetric left-right models with automatic
R-parity conservation, the theory below the $W_R$ scale is given by MSSM with
massive neutrinos and a pair of doubly charged superfields with masses in the
100 GeV range (with or without an extra pair of heavy Higgs doublets (M \geq 10
TeV) depending on the model). In this paper we study the unification prospects
for such theories and their phenomenological implications for collider
experiments. We study two versions of the theory, one with supersymmetry
breaking transmitted via the gauge and another where the same occurs via
gravitational forces. We point out that looking at multi $\tau$ final states
can considerably constrain the parameter space of the model.


title:
Analytic reduction of transition amplitudes in radiative electroweak
  processes

abstract:
  It is shown that the transition amplitudes of radiative electroweak processes
like $e^-e^+ \to \nu_e \ol{\nu}_e \ga$, $\ga e^- \to \nu_e \ol{\nu}_e e^-$, and
$\nu_e e^- \to \nu_e e^- \ga$ can be reduced and factorized into simpler forms
in the Standard Model. This method can be used in reducing many calculations of
complicated radiative electroweak processes in general.


title: The Sliding Singlet Mechanism with Gauge Mediated Supersymmetry Breaking

abstract:
  The sliding singlet mechanism is one of the most interesting solutions of the
triplet-doublet splitting problem. We analyze this mechanism in the gauge
mediated supersymmetry breaking scenario. We show that the sliding singlet
mechanism does not work in the naive gauge mediation scenario because of the
singlet linear terms derived from the gravity, although $F$ term is much
smaller than the one in the gravity mediation scenario. We also consider the
extension in order for the sliding singlet mechanism to work.


title: Dimensional Reduction of the Two-Higgs Doublet Model at High temperature

abstract:
  Dimensional reduction and effective field theory methods are applied to the
Two Higgs Doublet Model at finite temperature. A sequence of two effective
three-dimensional field theories which are valid on successively longer
distance scales is constructed. The resulting Lagrangian can be used to study
different aspects of the phase transition in this model as well as the
sphaleron rate immediately after the phase transition.


title: SU(3) Baryon Chiral Perturbation Theory and Long Distance Regularization

abstract:
  The use of SU(3) chiral perturbation theory in the analysis of low energy
meson-baryon interactions is discussed. It is emphasized that short distance
effects, arising from propagation of Goldstone bosons over distances smaller
than a typical hadronic size, are model-dependent and can lead to a lack of
convergence in the SU(3) chiral expansion if they are included in loop
diagrams. In this paper we demonstrate how to remove such effects in a chirally
consistent fashion by use of a cutoff and demonstrate that such removal
ameliorates problems which have arisen in previous calculations due to large
loop effects.


title:
A Simple Phenomenological Parametrization of Supersymmetry without
  R-Parity

abstract:
  We present a parametrization of the supersymmetric standard model without
R-parity that permits efficient phenomenological analyses of the full model
without a priori assumptions. Under the parametrization, which is characterized
by a single vacuum expectation value for the scalar components of the Y=-1/2
superfields, the expressions for tree-level mass matrices are quite simple.
They do not involve the trilinear R-parity violating couplings; however, the
bilinear {\mu}_i terms do enter and cannot be set to zero without additional
assumptions. We set up a framework for doing phenomenology and show some
illustrative results for fermion mass matrices and related bounds on
parameters. We find in particular that large values of tan(beta) can suppress
R-parity violating effects, substantially weakening experimental constraints.


title: Lepton Flavour Violation in String-Inspired Models

abstract:
  Lepton flavour violation has been proposed as a significant test of
supersymmetric unification. Here we show that such signals are also a generic
feature of supersymmetric string unified models in which there is no simple
unified gauge group. In realistic models of this kind which involve third
family Yukawa unification and large values of $\tan \beta$, there are generally
heavy right-handed (singlet) neutrinos of intermediate mass $M_{\nu}$, whose
couplings violate lepton flavour. To illustrate these effects we calculate the
rates for $\mu \to e \gamma$ and $\tau \to \mu gamma$ in the minimal
supersymmetric $SU(4)\times SU(2)\times SU(2)$ model. Including only the
minimum irreducible contributions, we find that both rates are enhanced
relative to similar models with low $\tan \beta$, with $\tau \to \mu gamma$
providing a decisive test of such models in the near future.


title: Positivity Constraints for off-Forward Parton Distributions

abstract:
  Off-Forward Parton Distributions (OFPD's) are new hadronic objects which may
be measured in various exclusive reactions. We derive non-trivial positivity
constraints for them that should allow to get extra restrictions for model
inputs.


title: Extremely high energy cosmic rays from relic particle decays

abstract:
  The expected proton and neutrino fluxes from decays of massive metastable
relic particles is calculated using the HERWIG QCD event generator. The
predicted proton spectrum can account for the observed flux of extremely high
energy cosmic rays beyond the Greisen-Zatsepin-Kuzmin cutoff, for a decaying
particle mass of O(10^{12}) GeV. The lifetime required is of O(10^{20}) yr if
such particles constitute all of the dark matter (with a proportionally shorter
lifetime for a smaller contribution). Such values are plausible if the
metastable particles are hadron-like bound states from the hidden sector of
supersymmetry breaking which decay through non-renormalizable interactions. The
expected ratio of the proton to neutrino flux is given as a diagonistic of the
decaying particle model for the forthcoming Pierre Auger project.


title:
$\pi$-$K$ scattering lengths at finite temperature in the
  Nambu--Jona-Lasinio model

abstract:
  The transition amplitude for $\pi K$ scattering is evaluated within the SU(3)
Nambu--Jona-Lasinio model. Ordering terms according to the expansion in $1/N_c$
leads to a box-like diagram, $t$ channel diagrams that admit scalar isoscalar
$(\sigma,\sigma')$ exchanges, and a $u$ channel exchange of a scalar isodoublet
$\sigma_K$ that has quantum numbers corresponding to the $K_0^*(1430)$. Both
the Pauli-Villars and O(3) regularization procedures are used to evaluate the
T=0 values of the $l=0$ scattering lengths $a_0^{3/2}$ and $a_0^{1/2}$. The
finite temperature dependence is studied. We find that the variation in the $t$
channel in the calculation of $a_0^{3/2}$ leads to a change in $a_0^{3/2}$ of a
factor of about two over the temperature range of T=150 MeV.


title:
Theoretical Uncertainties Associated with the Extraction of M_W at
  Hadron Colliders

abstract:
  In this contribution I briefly summarize several topics related to the
measurement of the W-boson mass, M_W, at hadron colliders.


title: dbar/ubar Asymmetry and the Origin of the Nucleon Sea

abstract:
  The Drell-Yan cross section ratios, $\sigma(p+d)/\sigma(p+p)$, measured in
Fermilab E866, have led to the first determination of $\bar d(x) / \bar u(x)$,
$\bar d(x) - \bar u(x)$, and the integral of $\bar d(x) - \bar u(x)$ for the
proton over the range $0.02 \le x \le 0.345$. The E866 results are compared
with predictions based on parton distribution functions and various theoretical
models. The relationship between the E866 results and the NMC measurement of
the Gottfried integral is discussed. The agreement between the E866 results and
models employing virtual mesons indicates these non-perturbative processes play
an important role in the origin of the $\bar d$, $\bar u$ asymmetry in the
nucleon sea.


title: Hadronic flux-tubes in the Dual Ginzburg-Landau Theory

abstract:
  We study the flux-tube solution in the dual Ginzburg-Landau (DGL) theory and
apply it to the understanding of quark-gluon-plasma (QGP) formation in the
ultra-relativistic heavy ion collision as the multi-flux-tube system. It is
concluded that the annihilation process of two flux-tubes can contribute to the
QGP formation with the energy deposition $\sim 4 GeV/fm^3$. Furthermore, we
study the glueball as the flux-tube ring by combining the DGL theory with the
string theory, and find the mass and the size as $\sim 1.2 GeV$ and $\sim 0.22
fm$, respectively.


title: On the Phase Diagram of QCD

abstract:
  We analyze the phase diagram of QCD with two massless quark flavors in the
space of temperature, T, and chemical potential of the baryon charge, mu, using
available experimental knowledge of QCD, insights gained from various models,
as well as general and model independent arguments including continuity,
universality, and thermodynamic relations. A random matrix model is used to
describe the chiral symmetry restoration phase transition at finite T and mu.
In agreement with general arguments, this model predicts a tricritical point in
the T mu plane. Certain critical properties at such a point are universal and
can be relevant to heavy ion collision experiments.


title: Axionic Hot Dark Matter in the Hadronic Axion Window

abstract:
  Mixed dark matter scenario can reconcile the COBE data and the observed large
scale structure. So far the massive neutrino with a mass of a few eV has been
the only discussed candidate for the hot dark matter component. We point out
that the hadronic axion in the so-called hadronic axion window, f_a \sim 10^6
GeV, is a perfect candidate as hot dark matter within the mixed dark matter
scenario. The current limits on the hadronic axion are summarized. The most
promising methods to verify the hadronic axion in this window are the resonant
absorption of almost-monochromatic solar axions from M1 transition of the
thermally excited $^{57}$Fe in the Sun, and the observation of the ``axion
burst'' in water \v{C}erenkov detectors from another supernova.


title:
Behavior of monopole trajectories in the instanton and anti-instanton
  system at finite temperature

abstract:
  We study the connection between monopoles and instantons in the Polyakov-like
gauge, and the behavior of the monopole trajectories generated by instantons at
finite temperature. The monopole trajectories become long and complicated at
the zero-temperature which can be regarded as monopole condensation. On the
other hand, they tend to become simple at finite temperature. It is suggested
that such a change is related to the confinement-deconfinement phase
transition.


title:
CP Violating Phase Difference between $B\to J/\psi K_S$ and $J/\psi K_S
  \pi^0$ from New Physics

abstract:
  The small P wave compoment of $B\to J/\psi K^*$ measured by CLEO makes it
practical to measure $\sin2\beta$ using $B^0\to J/\psi K^{*0}\to J/\psi K_S
\pi^0$, independent from $B^0\to J/\psi K_S$. Because these modes are color
suppressed, new physics enhanced color dipole $bsg$ coupling, as hinted from
the persistent ${\cal B}_{s.l.}$ and $n_C$ problems as well as the newly
observed large semi-inclusive $B\to \eta^\prime + X_s$ decay, may have
significant impact. We show that it may lead to a difference in the $\sin
2\beta$ measurements between $B^0\to J/\psi K_S$ and $J/\psi K_S \pi^0$
measureable at the B Factories in the near future.


title:
Flavor changing neutral current processes in $B$ and $K$ decays in the
  supergravity model

abstract:
  Flavor changing neutral current processes such as $b \to s \gamma$, $b \to s
l^+ l^-$, $b \to s \nu \bar{\nu}$, $\epsilon_K$, $\Delta m_B$, $K^+ \to \pi^+
\nu \bar{\nu}$ and $\K_L \to \pi^0 \nu \bar{\nu}$ are calculated in the
supersymmetric standard model based on supergravity. We consider two
assumptions for the soft supersymmetry breaking terms. In the minimal case soft
breaking terms for all scalar fields are taken to be universal at the GUT scale
whereas those terms are different for the squark/slepton sector and the Higgs
sector in the nonminimal case. In the calculation we have taken into account
the next-to-leading order QCD correction to the $b \to s \gamma$ branching
ratio, the results from the LEP II superparticles search, and the condition of
the radiative electroweak symmetry breaking. We show that $\Delta m_B$ and
$\epsilon_K$ can be enhanced up to 40% compared to the Standard Model values in
the nonminimal case. In the same parameter region the $b \to s \nu \bar{\nu}$,
$K^+ \to \pi^+ \nu \bar{\nu}$ and $\K_L \to \pi^0 \nu \bar{\nu}$ branching
ratios are reduced up to 10%. The corresponding deviation in the minimal case
is 20% for $\Delta m_B$ and $\epsilon_K$ and within 3% for the $b \to s \nu
\bar{\nu}$, $K^+ \to \pi^+ \nu \bar{\nu}$ and $\K_L \to \pi^0 \nu \bar{\nu}$.
For the $b \to s l^+ l^-$ process the significant deviation from the Standard
Model is realized only when the $b \to s \gamma$ amplitude has an opposite sign
to the Standard Model prediction. Significance on these results from possible
future improvements of the $b \to s \gamma$ branching ratio measurement and top
squark search is discussed.


title:
Diffractive $\jpsi$ production through Color-Octet mechanism at hadron
  colliders

abstract:
  We propose the color-octet mechanism combined with the two gluon exchange
model for the diffractive $J/\psi$ production in hadron collisions. In the
leading logarithmic approximation (LLA) in QCD, we find that the diffractive
$J/\psi$ production rate is related to the off-diagonal gluon density in the
proton and to the nonperturbative color-octet matrix element of $J/\psi$. The
rate is found to be very sensitive to the gluon density at very small values of
$x$ (down to $x=O(10^{-6})$). As a result, this process may provide a wide
window for testing the two-gluon exchange model, and may be particularly useful
in studying the small $x$ physics. And it may also be a golden place to test
the color-octet mechanism proposed by solving the $\psi'(J/\psi)$ surplus
problem at the Tevatron.


title: New and Old Jet Clustering Algorithms for Electron-Positron Events

abstract:
  Over the years, many jet clustering algorithms have been proposed for the
analysis of hadronic final states in $e^+e^-$ annihilations. These have
somewhat different emphasis and are therefore more or less suited for various
applications. We here review some of the most used and compare them from a
theoretical and experimental point of view.


title: Observing Doubly Charged Higgs Bosons in Photon-Photon Collisions

abstract:
  We discuss the possibility of observing doubly charged Higgs bosons in
$\gamma \gamma$ collisions. We find that one can increase the range of
observability close to the kinematic limit by a judicious choice of the
polarisations of the initial $e^-/ e^+$ beams as well as the initial laser beam
photons which are made to back-scatter from the former. We also note that, in a
large region of parameter space, the generally used lepton number violating
decay mode is dominated by the decay into a singly charged Higgs and a real or
virtual $W$-boson, giving rise to a large number of fermions in the final
state. This can qualitatively alter the strategy for discovering doubly-charged
scalars.


title:
Problems With Extracting $m_s$ from Flavor Breaking in Hadronic $\tau$
  Decays

abstract:
  A numerical error is pointed out in the existing expression for the order
$\alpha_s^2$ longitudinal component of the squared-mass (D=2) contribution to
the hadronic $\tau$ decay rate. The corrected version is found to be such that,
to order $\alpha_s^2$, each term in the resulting series is larger than the
previous one, ruling out the direct use of flavor breaking in hadronic $\tau$
decays as a means of extracting the strange quark mass. An alternate approach,
using model spectral functions previously developed for the
strangeness-changing scalar channel (and employed in alternate sum rule
analyses of $m_s$) as input to the $\tau$ decay analysis, is shown to provide
mutual consistency checks for the two different methods. The results for $m_s$
implied by $\tau$ decay data, and the existing model spectral function are also
presented.


title:
Isospin Breaking and the Extraction of $m_s$ from the $\tau$-Decay-Like
  Vector Current Sum Rule

abstract:
  Narison's $\tau$-decay-like sum rule for determining the strange quark mass
is re-investigated, taking into account isospin-breaking corrections in the
extraction of the input spectral functions from $e^+e^-\to hadrons$ data. The
corrections, estimated using experimental data on vector meson electromagnetic
decay constants and a QCD sum rule analysis of the 38 vector current
correlator, are shown to be especially large for the isoscalar case. The reason
such large corrections are natural is also explained. Due to the high degree of
cancellation in the original sum rule, the effect of these corrections on the
determination of $m_s$ is significant. A new central value $m_s=113-138 MeV$ is
found, in the $\bar{MS}$ scheme at 1 GeV$^2$, with significant (asymmetric)
errors associated with errors in the input experimental data.


title:
Estimates of Long-distance Contributions to the $B_s \to \gamma \gamma$
  Decay

abstract:
  We present first calculations of new long-distance contributions to $B_s \to
\gamma \gamma$ decay due to intermediate $D_s$ and $D_s^*$ meson states. The
relevant $\gamma$ vertices are estimated using charge couplings and transition
moment couplings. Within our uncertainties, we find that these long-distance
contributions could be comparable to the known short-distance contributions.
Since they have different Cabibbo-Kobayashi-Maskawa matrix-element factors,
there may be an interesting possibility of observing CP violation in this
decay.


title: Neutrino Propagation Through Matter

abstract:
  We discuss a simple approach to solve the transport equation for high-energy
neutrinos in media of any thickness. We present illustrative results obtained
with some specific models for the initial spectra of muon neutrinos and
antineutrinos propagating through a normal cold medium.


title: Polarized structure functions in a constituent quark scenario

abstract:
  Using a simple picture of the constituent quark as a composite system of
point-like partons, we construct the polarized parton distributions by a
convolution between constituent quark momentum distributions and constituent
quark structure functions. Using unpolarized data to fix the parameters we
achieve good agreement with the polarization experiments for the proton, while
not so for the neutron. By relaxing our assumptions for the sea distributions,
we define new quark functions for the polarized case, which reproduce well the
proton data and are in better agreement with the neutron data. When our results
are compared with similar calculations using non-composite constituent quarks
the accord with the experiments of the present scheme is impressive. We
conclude that, also in the polarized case, DIS data are consistent with a low
energy scenario dominated by composite constituents of the nucleon.


title: Light Propagation in Non-Trivial QED Vacua

abstract:
  Within the geometric optics approximation, we derive the light cone condition
for a class of homogeneous non-trivial QED vacua using the effective action
approach. Our result generalizes the ``unified formula'' suggested by Latorre,
Pascual and Tarrach which turns out to be a low-energy limit. We calculate the
velocity shifts induced by electromagnetic fields and finite temperature and
especially analyze the high-energy limit consistent with the loop
approximation.


title: Photoproduction of of l=1 Baryons: Quark Model versus Large N_c

abstract:
  We consider the electromagnetic decays of the orbitally-excited SU(6) 70-plet
baryons, to compare the predictions of the naive quark model with those of
large-N_c QCD. The helicity amplitudes measured in N^* photoproduction are
computed in a large-N_c effective field theory, based on a Hartree
approximation, and the amplitudes are fit to the current experimental data. Our
results indicate that the success of the naive quark model predictions cannot
be explained by large-N_c arguments alone. This is consistent with the
conclusions of an earlier study of the N^*\to N\pi decays, that utilized the
same approach.


title: Asymmetric neutrino Yukawa matrices and neutrino mixing

abstract:
  We study leptonic CKM mixing matrices when the neutrino Yukawa matrices are
antisymmetric which gives rise to mass patterns suitable to explain solar,
atmospheric and LSND neutrino oscillation experiments. Taking diagonal leptonic
matrices which can give rise to hierarchical lepton masses, we compute the
leptonic CKM matrix.


title: Spin Correlations in Production and Decay of Charginos

abstract:
  We study the production of charginos e^+ e^- -> chi^+_i chi^-_j, (i,j=1,2)
with polarized beams and the subsequent decays chi^+_i -> chi^0_k ell^+ nu and
chi^-_j -> chi^0_l ell^- nu, (k,l=1,...,4), including the complete spin
correlations between production and decay. Analytical formulae are presented
for the joint spin-density matrix of the charginos, for the chargino decay
matrix and for the differential cross section of the combined processes of
production and decays. We present numerical results for pair production of the
lighter chargino with unpolarized beams and the leptonic decay of chi^+_1 into
the lightest neutralino chi^0_1. The lepton angular distribution and the
forward-backward asymmetry are studied in four representative scenarios for
sqrt{s}=192 GeV and sqrt{s}=200 GeV.


title: Test of Special Relativity and Equivalence principle from K Physics

abstract:
  A violation of Local Lorentz Invariance (VLI) and hence the special theory of
relativity or a violation of equivalence principle (VEP) in the Kaon system
can, in principle, induce oscillations between $K^0$ and $\bar{K}^0$. We
construct a general formulation in which simultaneous pairwise diagonalization
of mass, momemtum, weak or gravitational eigenstates is not assumed. %and the
maximum attainable %velocities of the velocity eigenstates are different. We
discuss this problem in a general way and point out that, as expected, the VEP
and VLI contributions are indistinguishable. We then insist on the fact that
VEP or VLI can occur even when CPT is conserved. A possible CP violation of the
superweak type induced by VEP or VLI is introduced and discussed. We show that
the general VEP mechanism (or the VLI mechanism, but not both simultaneously),
with or without conserved CPT, could be clearly tested experimentally through
the energy dependence of the $K_L-K_S$ mass difference and of $\eta_{+-}$,
$\eta_{00}$, $\delta$. Constraints imposed by present experiments are
calculated.


title: Tools for Tunneling

abstract:
  If the universe is trapped and cooled in a metastable false vacuum state,
that state will eventually decay by bubble nucleation and expansion. For
example, many extensions of the standard model incorporate new scalar fields
whose potential has a local minimum at the origin but a global minimum
elsewhere, to which the vacuum will eventually tunnel. I calculate the lifetime
of the false vacuum, and the field profile of the bubble after tunneling, for
any potential that is approximately a polynomial of degree <= 4 near the false
vacuum. Essentially exact results are given for a single field; for multiple
fields the given action is a strict upper bound.


title: Radiative Corrections to W and Quark Propagators in the Resonance Region

abstract:
  We discuss radiative corrections to W and quark propagators in the resonance
region, |s-M^2| \lsim M*Gamma. We show that conventional mass renormalization,
when applied to photonic or gluonic corrections, leads in next to leading order
(NLO) to contributions proportional to [M*Gamma/(s-M^2)]^n, (n=1,2...), i.e. to
a non-convergent series in the resonance region, a difficulty that affects all
unstable particles coupled to massless quanta. A solution of this problem,
based on the concepts of pole mass and width, is presented. It elucidates the
issue of renormalization of amplitudes involving unstable particles and
automatically circumvents the problem of apparent on-shell singularities. The
roles of the Fried-Yennie gauge and the Pinch Technique prescription are
discussed. Because of special properties of the photonic and gluonic
contributions, and in contrast with the Z case, the gauge dependence of the
conventional on-shell definition of mass is unbounded in NLO. The evaluations
of the width in the conventional and pole formulations are compared and shown
to agree in NLO but not beyond.


title: Maximal mixing neutrino models

abstract:
  We account for the solar and atmospheric neutrino problems by introducing
maximal mixing between conventional and sterile neutrino partners. We achieve
this by invoking a seesaw-like mechanism which not only provides us with
maximally mixed neutrino/sterile-neutrino mass eigenstates but also accounts
for the relative suppression of the neutrino masses compared to the charged
fermion masses. In obtaining such an extended seesaw mechanism we are required
to introduce a new U(1) global symmetry together with an extended Higgs sector.


title: Trouble for MAC

abstract:
  We show that the next-to-leading corrections to the kernel of the gap
equation can be large and of opposite sign to the lowest order kernel, in the
presence of a gauge boson mass. This calls into question the reliability of the
Most Attractive Channel hypothesis.


title: Mass and flavor from strong interactions

abstract:
  We provide an economical description of mass and flavor based on strong
interactions and some dynamical assumptions. We include a discussion of CP
violation in the quark sector and its relation to neutrino masses.


title: Renormalization Group Naturalness of GUT Higgs Potentials

abstract:
  We analyze the symmetry-breaking patterns of grand unified theories from the
point of view of a recently-proposed criterion of renormalization-group
naturalness. We perform the analysis on simple non-SUSY SU(5) and SO(10) and
SUSY SU(5) GUTs. We find that the naturalness criterion can favor
spontaneous-symmetry-breaking in the direction of the smallest of the maximal
little groups. Some differences between theories with and without supersymmetry
are also emphasized.


title: Production of Higgs with Z--boson by an electron in external fields

abstract:
  The rate of associative production of Higgs and $Z$--bosons by charged
leptons in the field of a plane electromagnetic wave of arbitrary intensity and
in the constant crossed field is obtained. The cross section is examined as a
function of particle energies and external field intensities for various values
of the Higgs boson mass. It is shown, that the photoproduction cross section
increases logarithmically at super high energies up to the values, that
essentially exceed the cross section of the reaction $e^+e^-\to ZH,$ which, at
present, is considered as the most probable channel of Higgs boson production.


title: Instantons and Monopoles for Nonperturbative QCD

abstract:
  We study the nonperturbative QCD in terms of topological objects, i.e.,
QCD-monopoles and instantons. In the 't Hooft abelian gauge, QCD is reduced
into an abelian gauge theory with QCD-monopoles, and the confinement mechanism
can be understood with the dual superconductor picture. Regarding the flux-tube
ring as the glueball, we study the glueball properties by combining the dual
Ginzburg-Landau theory and the Nambu-Goto action. We find the strong
correlations between instantons and monopole world-lines both in the continuum
theory and in the lattice QCD. The nonperturbative QCD vacuum is filled with
instantons and monopoles, and dense instantons generate a macroscopic network
of the monopole world-line, which would be responsible for the confinement
force in the infrared region.


title: Scale-Invariant Dynamical Fluctuations in Jet Physics

abstract:
  An interpretation of scale-invariant multiplicity fluctuations inside
hadronic jets is presented. It is based on the branching mechanism with the
angular ordering of soft partons in sequential branchings. A relationship with
fractal distributions is demonstrated. The model takes into account the
finiteness of the number of particles produced in jets (finite energy) and
leads to a good description of the multifractal fluctuations observed in E+E-
processes.


title: A matrix-element-based modification of the parton shower

abstract:
  The transverse momentum distribution of W+/- bosons at hadron colliders is
well described by a parton-shower model for small pT values, but not for large
ones. This article is an attempt to give a better description of the
distribution by using corrections derived from the matrix-element formalism.
The parton shower for qqbar->W+/- has been modified to resemble the matrix
elements of qqbar->gW and qg->q'W at large pT values. Comparisons between
different approaches are presented at sqrt{s}=1800 GeV. The results are also
compared with experimental data from the D0 collaboration at Fermilab.


title: Neutrino self-energy and dispersion in a medium with magnetic field

abstract:
  We calculate the one-loop thermal self-energy of a neutrino in a constant and
homogeneous magnetic field to all orders in the magnetic field strength using
Schwinger's proper time method. We obtain the dispersion relation under various
conditions.


title:
Controlling Rescattering Effects in Constraints on the CKM Angle
  $\gamma$ arising from $B\to\pi K$ Decays

abstract:
  It has recently been pointed out that the observables of the decay $B^+\to
K^+\bar{K^0}$ and its charge conjugate allow us to take into account
rescattering effects in constraints on the CKM angle $\gamma$ arising from
$B^\pm\to\pi^\pm K$ and $B_d\to\pi^\pm K^\pm$ modes, and that they play an
important role to obtain insights into final-state interactions. In this paper,
the formalism needed to accomplish this task is discussed in detail.
Furthermore, using a transparent model to describe the rescattering processes,
as well as electroweak penguins, we calculate the quantities parametrizing the
$B^+\to\pi^+ K^0$ and $B_d^0\to\pi^- K^+$ decay amplitudes for specific
examples, and illustrate the constraints on $\gamma$ arising from the
corresponding observables. Although this model is very crude, it shows nicely
the power of $B^\pm\to K^\pm K$ both to include the rescattering effects in the
bounds on $\gamma$ and to obtain insights into final-state interactions.
Moreover this model exhibits the interesting feature that the combined
branching ratio BR$(B^\pm\to K^\pm K)$ may be considerably enhanced through
rescattering processes, as was recently pointed out within a general framework.


title: Vector, Axial, Tensor and Pseudoscalar Vacuum Susceptibilities

abstract:
  Using a recently developed three-point formalism within the method of QCD Sum
Rules we determine the vacuum susceptibilities needed in the two-point
formalism for the coupling of axial, vector, tensor and pseudoscalar currents
to hadrons. All susceptibilities are determined by the space-time scale of
condensates, which is estimated from data for deep inelastic scattering on
nucleons.


title:
ISAJET 7.37: A Monte Carlo Event Generator for $pp$, $\bar pp$, and
  $e^+e^-$ Interactions

abstract:
  ISAJET is a Monte Carlo event generator for $pp$, $\bar pp$, and $e^+e^-$
interactions at high energies. This document summarizes the physics underlying
the program and describes how to use it.


title: Study of Trilinear Gauge Boson Couplings at the Tevatron Collider

abstract:
  We review studies of the trilinear gauge boson couplings at the Tevatron
proton-antiproton collider from data collected by the CDF and D0 collaborations
during the period 1992--1996. The gauge boson couplings are a fundamental
prediction of the standard model, resulting from the non-Abelian nature of the
theory. Therefore, experimental tests of the couplings are of foremost
importance. We introduce the experimental results by reviewing the effective
Lagrangian formalism, the indirect constraints on the couplings from low-energy
experiments, and the expected values of the couplings in theories beyond the
standard model. Finally, we consider the prospects for future measurements.


title: Quark Flavor Tagging in Polarized Hadronic Processes

abstract:
  We describe a general approach to quark flavor tagging in polarized hadronic
processes, with particular emphasis on semi-inclusive deep inelastic
scattering. A formalism is introduced that allows one to relate chosen quark
flavor polarizations to an arbitrary combination of final-state hadron spin
asymmetries. Within the context of the presented formalism, we quantify the
sensitivity of various semi-inclusive hadron asymmetries to the light quark
flavors. We show that unpolarized Lambda's may allow one to measure strange
quark and antiquark polarizations independently. We also highlight several
applications of our formalism, particularly to measurements intended to probe
further the spin structure of the nucleon.


title: Effective Field Theory of Heavy Mesons

abstract:
  In this paper we present a detailed formulation for a recently proposed
effective field theory to describe the nonperturbative QCD dynamics of heavy
mesons. This effective theory incorporates with heavy quark symmetry (HQS) and
the heavy quark effective theory (HQET). Heavy mesons in this theory are
constructed as composite particles of a heavy quark bounded with the light
degrees of freedom. The heavy meson properties in the heavy quark limit and the
$1/m_Q$ corrections can then be explicitly evaluated from this effective
theory. All the basic parameters of the HQET, namely, the heavy quark mass
$m_Q$, the heavy meson residual mass $\overline{\Lambda}$, and the HQS breaking
mass parameters $\lambda_1$ and $\lambda_2$, are consistently determined.
$\lambda_1$ is found to be small due to a large cancellation between the heavy
quark kinetic energy and the chromo-electric interaction between the heavy
quark and light degrees of freedom. We also evaluate the Isgur-Wise function,
the decay constant, and the axial-vector coupling constant of heavy mesons.


title: Fermion Mass Hierarchy without Flavour Symmetry

abstract:
  We discuss a supersymmetric grand unified model which has gauge group SU(5)
$\times$ SU(5) $\times$ SU(5), with matter fields transforming asymmetrically
under different gauge SU(5) groups. We observe that the gauge structure of the
model leads to approximate texture zero structures in fermion mass matrices and
a natural hierarchy in the Yukawa couplings. The proton lifetime is estimated
to be larger than $10^{34}$ years in this model. As in more conventional
supersymmetric GUT models with product gauge groups, this model possesses no
tensor fields with rank higher than 2, so that it might arise from a level 1
string construction.


title: On the enhancement of the QCD running coupling

abstract:
  We show that the existence of the fundamental ultraviolet cut-off (minimal
scale) fixed by weak interactions enhances the QCD running coupling evaluated
at one quantum loop level, starting at the scale in the vicinity of the
cut-off. The enhancement of the QCD running coupling could completely explain
the observed anomalous TeVatron and HERA data. The QCD in the noncontractible
space is not an asymptotically free gauge theory.


title:
Impacts on searching for signatures of new physics from $K^+ \to \pi^+
  \nu \bar{\nu}$ decay

abstract:
  Impacts on new physics search from $\bbbar, \kkbar$ mixings and the rare
decay $\kplusdecay$ are discussed. We show that, in a certain class of new
physics models, the extra contributions to those processes can be parametrized
by its ratio to the standard model (SM) contribution with the common CKM
factors. We introduce two ratios to measure the new physics contributions,
$R_1$ for $\xd$ and $\ek$ parameters, and $R_2$ for $\kplusdecay$ decay. Then,
the experimentally allowed region for the new physics contributions can be
given in terms of $R_1, R_2$ and the CP violating phase $\delta$ of the CKM
matrix. We find constraints on $R_1$ and $\cosd$ by taking account of current
experimental data and theoretical uncertainties on $\bbbar$ and $\kkbar$
mixings. We also study impacts of future improved measurements on
($R_1,R_2,\cosd$) basis. As typical examples of new physics models, we examine
contributions to those processes in the minimal supersymmetric SM and the two
Higgs doublet model.


title: Single Top Quark and Light Higgs Boson at Tevatron

abstract:
  Search for single top quark and Higgs boson production is among the main
goals for the upgraded Tevatron. We study the feasibility of single top quark
and Higgs boson search at Tevatron both together since these processes have
very similar final state signatures and so backgrounds. Calculation of the
cross sections and a detailed analysis of various kinematic distributions for
signal and for main backgrounds has been performed.
  As a result of this study an opimized set of cuts has been worked out for
background suppression and for extraction of the signal. This study gives proof
to the possibility of testing the nature of the {\wtb} coupling and of a direct
measurement of the {\vtb} CKM parameter. The \bbbar -- pair effective mass
distribution study allows to extract the signal of Higgs with mass up to about
$100\gev$ at $\sqs = 2\tev$ and up to about $120\gev$ at $\sqs = 4\tev$ for
integrated luminosity $L= 1000\ipb$.


title: The CKM Matrix and Its Origin

abstract:
  In the context of the supersymmetric unification model in which the massless
sector contains extra particles beyond those in the minimal supersymmetric
standard model, we obtain mixings between quarks (leptons) and the extra
particles which are closely intertwined with Yukawa hierarchies. With the
assumption that the unification gauge group $G$ includes $SU(2)_R$, it is shown
that the non-trivial texture of the CKM matrix originates from the
extra-particle mixings. The CKM matrix of quarks emerges as a consequence of
the mixings between the down-type quarks and colored Higgses, both of which are
$SU(2)_L$-singlets. On the other hand, the CKM matrix of leptons is due to the
mixings stemming from the seesaw mechanism with the hierarchical Majorana mass
matrix of right-handed neutrinos.


title: CP violation with BaBar

abstract:
  The BABAR experiment is a new generation detector located at the SLAC B
factory PEP-II ring which should start taking data at the end of 1999. Its main
goal is the study of CP violation in the B0-B0b system. After explaining the
nature of this CP violation, I review the scientific program for achieving this
study in many different modes, in the light of the recent developments obtained
both on the experimental and theoretical side. Implications for the Standard
Model are then discussed.


title:
Top-quark pair production via polarized and unpolarized protons in the
  supersymmetric QCD

abstract:
  The QCD corrections to the top-quark pair production via both polarized and
unpolarized gluon fusion in $pp$ collisions are calculated in the Minimal
Supersymmetric Model(MSSM). We find the MSSM QCD corrections can reach 4% and
may be observable in future precise experiments. Furthermore, we studied the CP
violation in the MSSM, our results show that the CP violating parameter is
sensitive to the masses of SUSY particles (It becomes zero, when the c.m.
energy is less than twice the masses of both gluino and stop quarks.) and may
reach $10^{-3}$.


title:
The Effect of Higher Order Corrections to the BFKL Equation on the
  Perturbative Pomeron

abstract:
  We discuss the significance of the next-to-leading order term in the BFKL
equation on the energy dependence of diffractive processes controlled by the
perturbative QCD pomeron. It is shown that whereas the large negative
corrections do indeed reduce the rate of growth of diffractive amplitudes with
increasing energy, this reduction is considerably less than previously
expected.


title: First Results with a new Method for calculating 2-loop Box-Functions

abstract:
  We describe a first attempt to calculate scalar 2-loop box-functions with
arbitrary internal masses, applying a novel method proposed in hep-ph/9407234.
Four of the eight integrals are accessible to integration by means of the
residue theorem, leaving a rational function in the remaining variables. The
result of the procedure is a three- or sometimes two-dimensional integral
representation over a finite volume that can be further evaluated using
numerical methods.


title: The Bremsstrahlung Process Nu_Tau -> Nu_e E+ E- Gamma

abstract:
  The bremsstrahlung process Nu_Tau -> Nu_e E+ E- Gamma is the dominant
photon-producing decay of heavy Tau neutrinos with m_Nu_Tau > 2 m_e so that
this process is instrumental for supernova 1987A constraints on the properties
of these particles, notably on their mixing amplitude with Nu_e. We calculate
the rate of the bremsstrahlung process as well as the photon spectrum and the
angular distribution relative to the spin direction of the parent neutrino. We
carefully pay attention to the difference between Dirac and Majorana neutrinos.


title: Relativistic properties of the quark-antiquark potential

abstract:
  The relativistic transformation properties of the heavy quark-antiquark
interaction potential are considered in the framework of the relativistic quark
model. A special attention is paid to the long-range (confining) contribution
to the spin-independent part of qq bar interaction. The retardation effects are
consistently taken into account.


title:
Effect of strong magnetic field on the first-order electroweak phase
  transition

abstract:
  The broken-symmetry electroweak vacuum is destabilized in the presence of a
magnetic field stronger than a critical value. Such magnetic field may be
generated in the phase transition and restore the symmetry inside the bubbles.
A numerical calculation indicates that the first-order phase transition is
delayed but may be completed for a sufficient low value of the Higgs mass
unless the magnetic field is extremely high.


title: Quark Orbital-Angular-Momentum Distribution in the Nucleon

abstract:
  We introduce gauge-invariant quark and gluon angular momentum distributions
after making a generalization of the angular momentum density operators. From
the quark angular momentum distribution, we define the gauge-invariant and
leading-twist quark {\it orbital} angular momentum distribution $L_q(x)$. The
latter can be extracted from data on the polarized and unpolarized quark
distributions and the off-forward distribution $E(x)$ in the forward limit. We
comment upon the evolution equations obeyed by this as well as other orbital
distributions considered in the literature.


title: Chiral Fluid Dynamics and Collapse of Vacuum Bubbles

abstract:
  We study the expansion dynamics of a quark-antiquark plasma droplet from an
initial state with restored chiral symmetry. The calculations are made within
the linear $\sigma$ model scaled with an additional scalar field representing
the gluon condensate. We solve numerically the classical equations of motion
for the meson fields coupled to the fluid-dynamical equations for the plasma.
Strong space-time oscillations of the meson fields are observed in the course
of the chiral transition. A new phenomenon, the formation and collapse of
vacuum bubbles, is also predicted. The particle production due to the
bremsstrahlung of the meson fields is estimated.


title:
R-parity violation, sneutrino mixing phenomena and CP-violation in p
  \bar p -> sneutrino -> l^+ l^- + X

abstract:
  The sneutrino resonance reactions p \bar p -> sneutrino -> l^+ l^- +X, for
l=e,\mu,\tau, in the MSSM without R-parity are considered. We perform a
cross-section analysis and show that present limits on some products of
R-parity violating couplings in the sneutrino sector can be significantly
improved in future upgraded Fermilab Tevatron runs. Furthermore, we introduce
CP-violating and CP-conserving \tau-spin asymmetries which are generated
already at the TREE-LEVEL in the reaction p \bar p -> sneutrino -> \tau^+
\tau^- +X if there is muon-sneutrino - \bar muon-sneutrino mixing and that
vanish in the SM. We find, for example, that for muon-sneutrino masses in the
range 150 GeV < m_{muon-sneutrino} < 450 GeV, these spin asymmetries reach ~ 20
- 30% and ~ 10% for mass splitting between the muon-sneutrino CP-odd and
CP-even states at the level of \Delta m ~ \Gamma and \Delta m ~ \Gamma/4,
respectively, where \Gamma is the muon-sneutrino width. Both the CP-violating
and the CP-conserving spin asymmetries should be detectable in future Tevatron
runs even for a heavy sneutrino with a mass < 500 GeV. If detected, such
asymmetries - being proportional to the mass splitting between the CP-even and
CP-odd sneutrino states - may serve as a strong indication for the existence of
the sneutrino mixing phenomenon.


title:
A detailed determination of the a priori mixing angles in non-leptonic
  decays of hyperons

abstract:
  Non-leptonic Decays of Hyperons can provide a detailed determination of the a
priori mixing angles that appear in physical hadrons in the approach in which
non-perturbative flavor and parity violations are present in tiny pieces of the
hadron mass operator. The determination of such angles in these decays will
provide a bench mark to test their necessary universality-like property in
other types of decays. Our main result is that the magnitudes of the a priori
mixing angles can be determined quite accurately.


title:
A Priori Mixed Hadrons, Weak Radiative and Non-leptonic Decays of
  Hyperons

abstract:
  A priori mixings of eigenstates in physical states are quantum mechanical
effects well known in several realms of physics. The possibility that such
effects are also present in particle physics, in the form of flavor and parity
mixings, is studied. Applications to weak radiative and non-leptonic decays of
hyperons are discussed.


title:
Twopion decays of K mesons, K_L-K_S mass difference and the Dalitz
  decays of K_L

abstract:
  Two pion Decays of K mesons, K_L-K_S mass difference, two photon decay and
the Dalitz decays of K_L are studied systematically by assuming that their
amplitude can be described in terms of a sum of short distance and long
distance contributions. Dominance of the short distance effect on the K_L-K_S
mass difference will be checked by the Dalitz decays of K_L in a way consisten
with the two pion decays of K mesons and the two photon decay of K_L.


title: Probing anomalous top quark couplings at e\gamma colliders

abstract:
  We study in the effective Lagrangian approach the possibility of probing
anomalous top quark charged current couplings in the single top production at a
high energy e\gamma collider. We analyzed all possible dimension-six
CP-conserving operators which can give rise to an anomalous Wtb coupling which
represent new physics effect generated at a higher energy scale. For those
operators which also give rise to anomalous Zbb_bar or right-handed Wtb
couplings, we find that they are strongly constrained by the existing R_b and
b->s\gamma data. As a result, a collider with a luminosity of the order of 100
fb^{-1} is required to observe the anomalous effects. For other operators which
currently subject to no strong constraints, the high energy e\gamma collider
can probe their couplings effectively because of the clean environment of such
a collider.


title: $KN$ Sigma Terms, Strangeness in the Nucleon, and DA$\Phi$NE

abstract:
  Expanded and updated version of a talk originally presented at ``IVth Int.
Symp. on Pion--Nucleon Physics and the Structure of the Nucleon'', Bad Honnef,
9--13 September 1991, originally published in $\pi N$ Newletter 6 (1992)
21--32.
  Table of contents:
  1. Introduction.
  2. $\sigma$--terms and ``measurements'' of the strange--quark scalar density
of the nucleon.
  3. Methods of extrapolation to $q^2 = t = \omega^2 = 0$: a subjective review:
  3.1. The ``improved'' Altarelli--Cabibbo--Maiani method.
  3.2. The Fubini--Furlan analysis of meson-nucleus scattering lengths.
  3.2. The ``unitarized'' version of the Cheng--Dashen theorem.
  4. Capabilities for a $\bar{K}N$--scattering experiment at DA$\Phi$NE.
  5. ``Envoi''.


title:
Multi-pion Bose-Einstein Correlation effects on three-pion
  interferometry

abstract:
  Multi-pion correlations effect on three-pion interferometry is studied. It is
shown that multi-pion correlations decrease both the apparent radius of the
source and the coherent source parameter derived from three-pion
interferometry. The data of OPAL group are discussed.


title: R Parity Violation: Constraints and Implications

abstract:
  The constraints on trilinear R parity violating couplings $\lambda'_{ijk}$
following from ({\em i}) the neutrino mass resulting due to the induced vacuum
expectation value for the sneutrino and (ii) the charm squark interpretation
for the HERA anomalous events are discussed in this talk.}


title: Scalar mesons in the Nambu--Jona-Lasinio model with 't Hooft interaction

abstract:
  We calculate the mass spectra of the pseudoscalar and scalar meson nonets in
the Nambu--Jona-Lasinio model with the 't Hooft interaction. We obtain
satisfactory result for the pseudoscalar mesons. For the scalar mesons, the 't
Hooft interaction somewhat increases the values of the masses. However, it is
not sufficient to explain the whole scalar mass spectrum. The situation could
be improved for the $\sigma$ and $f_0$ mesons through mixing with the glueball
state. For the description of the masses of $a_0$ and $\kstar$ mesons, it is
necessary to involve the other models. The strong decay widths of the scalar
mesons are described.


title:
Photon-Photon Physics in Very Peripheral Collisions of Relativistic
  Heavy Ions

abstract:
  In central collisions at relativistic heavy ion colliders like the
Relativistic Heavy Ion Collider RHIC/Brookhaven and the Large Hadron Collider
LHC (in its heavy ion mode) at CERN/Geneva, one aims at detecting a new form of
hadronic matter - the Quark Gluon Plasma. It is the purpose of this review to
discuss a complementary aspect of these collisions, the very peripheral ones.
Due to coherence, there are strong electromagnetic fields of short duration in
such collisions. They give rise to photon-photon and photon-nucleus collisions
with high flux up to an invariant mass region hitherto unexplored
experimentally. After a general survey photon-photon luminosities in
relativistic heavy ion collisions are discussed. Special care is taken to
include the effects of strong interactions and nuclear size. Then photon-photon
physics at various gamma-gamma-invariant mass scales is discussed. The region
of several GeV, relevant for RHIC is dominated by QCD phenomena (meson and
vector meson pair production). Invariant masses of up to about 100 GeV can be
reached at LHC, and the potential for new physics is discussed. Photonuclear
reactions and other important background effects, especially diffractive
processes are also discussed. A special chapter is devoted to lepton-pair
production, especially electron-positron pair production; due to the strong
fields new phenomena, especially multiple e+-e- pair production, will occur
there.


title: Testing factorization of charmonium production

abstract:
  Within the NRQCD factorization approach the production of heavy quarkonia can
be calculated in perturbative QCD in terms of a few
production-process-independent NRQCD matrix elements. We test the universality
of these long-distance matrix elements by comparing their values as determined
from charmonium production at p pbar, e p, and e+ e- colliders, and in Z^0,
Upsilon, and B decays.


title: Conformal Mapping, Power Corrections, and the QCD Bound State Spectrum

abstract:
  We analyze the heavy quark bound state spectrum using an order-dependent
conformal mapping to re-sum the perturbative expansion for current correlators.
The procedure consists of two main steps. Firstly, the Borel plane structure of
the truncated perturbative expression is modified to ensure consistency with
the operator product expansion. This is analogous to a resummation of infrared
renormalon chains. Secondly, this perturbative expansion is conformally mapped
to a new series with improved convergence properties. This approach may be
shown to induce power corrections consistent with existing condensates, and the
resulting expansion may be ordered in powers of an infrared-analytic effective
coupling. The technique is then applied to $c\bar{c}$ and $b\bar{b}$ sum rules
without any explicit introduction of vacuum condensate parameters. Ground state
masses for the vector, axial--vector, and $A'$ channels are well reproduced,
while results for the scalar--pseudoscalar mass splitting are less impressive.


title: The Plasmon Damping Rate for T -> T_C

abstract:
  The plasmon damping rate in scalar field theory is computed close to the
critical temperature. It is shown that the divergent result obtained in
perturbation theory is a consequence of neglecting the thermal renormalization
of the coupling. Taking this effect into account, a vanishing damping rate is
obtained, leading to the critical slowing down of the equilibration process.


title: Low Q^2 Jet Production at HERA in Next-to-Leading Order QCD

abstract:
  We present next-to-leading order calculations of one- and two-jet production
in eP collisions at HERA for photon virtualities in the range 1<Q^2<100 GeV^2.
Soft and collinear singularities are extracted using the phase space slicing
method. Numerical results are presented for HERA conditions with the Snowmass
jet definition. The transition between photoproduction and deep-inelastic
scattering is investigated in detail. We compare two approaches, the usual
deep-inelastic theory, where the virtual photon couples only directly to quarks
and antiquarks, and the photoproduction approach, where the photon couples
either in the direct way or in the resolved way via the parton constituents of
the virtual photon with the proton constituents. Finally we compare with recent
H1 data of the dijet rate obtained for various photon virtualities Q^2 with
special attention to the region, in which two jets have equal transverse
momenta.


title:
Next-to-Leading Order QCD Corrections to the Polarized Photoproduction
  of Heavy Flavors

abstract:
  We present a calculation of the next-to-leading order (O(alpha_s^2 alpha))
QCD corrections to heavy flavor photoproduction with longitudinally polarized
beams. We apply our results to study the longitudinal spin asymmetry for the
total charm quark production cross section which will be utilized by the
forthcoming COMPASS experiment at CERN to obtain first direct information on
the polarized gluon density Delta g. We also briefly discuss the main
theoretical uncertainties inherent in this calculation. In particular we
demonstrate that the factorization scale dependence is considerably reduced in
next-to-leading order.


title: Tau Neutrino Appearance with a 1000 Megaparsec Baseline

abstract:
  A high-energy neutrino telescope, such as the operating AMANDA detector, may
detect neutrinos produced in sources, possibly active galactic nuclei or
gamma-ray bursts, distant by a thousand megaparsecs. These sources produce
mostly nu_e or nu_mu neutrinos. Above 1 PeV, nu_e and nu_mu are absorbed by
charged-current interactions in the Earth before reaching the opposite surface.
However, the Earth never becomes opaque to nu_tau since the tau^- produced in a
charged-current nu_tau interaction decays back into nu_tau before losing
significant energy. This preferential penetration of tau neutrinos through the
Earth above 10^14 eV provides an experimental signature for neutrino
oscillations. The appearance of a nu_tau component would be evident as a flat
zenith angle dependence of a source intensity at the highest neutrino energies.
Such an angular dependence would indicate nu_tau mixing with a sensitivity to
delta-m^2 as low as 10^-17 eV^2, for the farthest sources. In addition, the
presence of tau neutrino mixing would provide the opportunity for neutrino
astronomy well beyond the PeV cutoff, possibly out to the energies matching
those of the highest energy protons observed above 10^20 eV.


title: CP Violation, Higgs Couplings, and Supersymmetry

abstract:
  Supersymmetric extensions of the standard model generically contain
additional sources of CP violation. We discuss how at one loop a potentially
large CP violating coupling of the lightest Higgs, h^0, to leptons is induced
in the minimal supersymmetric standard model (MSSM). The CP violating couplings
of h^0 in extensions of the MSSM, such as the next-to-minimal supersymmetric
standard model (NMSSM) are also considered. We indicate how this CP violation
might be observed; in particular a polarization-dependent production asymmetry,
in the context of a muon collider, provides a means to access this coupling
cleanly. In the MSSM, existing limits on the electric dipole moment (EDM) of
the electron, coupled with standard universality assumptions, severly
constrains any such signal. Nevertheless, extensions of the MSSM, such as the
NMSSM, allow CP-violating signals as large as 100%.


title: Approach to Perturbative Results in the N-Delta Transition

abstract:
  We show that constraints from perturbative QCD calculations play a role in
the nucleon to Delta(1232) electromagnetic transition even at moderate momentum
transfer scales. The pQCD constraints, tied to real photoproduction data and
unseparated resonance response functions, lead to explicit forms for the
helicity amplitudes wherein the E2/M1 ratio remains small at moderately large
momentum transfer.


title:
Effect of Jet Quenching on High-$p_T$ Hadron Spectra in High-energy
  Nuclear Collisions

abstract:
  Since large $p_T$ particles in high-energy hadronic or nuclear collisions
come from jet fragmentation, jet quenching due to parton energy loss in dense
matter will cause the suppression of large $p_T$ hadron spectra in high-energy
heavy-ion collisions. Assuming an effective energy loss $dE/dx$ for the high
$E_T$ partons, effective jet fragmentation functions are constructed in which
leading hadrons will be suppressed. Using such effective fragmentation
functions, high $p_T$ hadron spectra and particle suppression factors relative
to $pp$ collisions are estimated in central high-energy nuclear collisions with
a given range of the assumed $dE/dx$. It is found that the suppression factors
are very sensitive to the value of the effective energy loss. Systematic
nuclear and flavor dependence of the hadron spectra are also studied.


title: Higgs and Technicolor Goldstone Bosons at a Muon Collider

abstract:
  I discuss the exciting prospects for Higgs and technicolor Goldstone boson
physics at a muon collider.


title: Massive Doublet Leptons

abstract:
  Massive vector-like electroweak doublets are generic in many extensions of
the standard model. Even though one member of the doublet is necessarily
electrically charged these particles are not easily detected in collider
experiments. The neutral and charged states within the doublet are split by
electroweak symmetry breaking. In the absence of mixing with other states, the
radiatively generated splitting is in the range 200 - 350 MeV for m > mZ/2. The
charged state decays to the neutral one with an O(cm) decay length,
predominantly by emission of a soft charged pion. The best possibility to
detect these massive charged particles is to trigger on hard initial state
radiation and search for two associated soft charged pions with displaced
vertices. The mass reach for this process at LEPII is limited by luminosity
rather than kinematics.


title: Quarkonium Mass Splitting Revisited: Effects of Closed Mesonic Channels

abstract:
  Modifications of the mass spectrum the quarkonium induced by its virtual
dissociation into a pair of heavy mesons is considered. Coupling between quark
and mesonic channels results in noticeable corrections to spin-dependent mass
splitting. In particular, the observable hierarchy of mass splittings in the
$\chi_c, \chi_b$ and $\chi'_b$ multiplets is reproduced.


title:
Radiative electroweak effects in deep inelastic scattering of polarized
  leptons by polarized nucleons

abstract:
  The one-loop electroweak radiative correction of the lowest order to lepton
current for deep inelastic scattering of longitudinally polarized leptons by
polarized nucleons is obtained in model independent way. The detailed numerical
analysis within kinematical requirements of future polarization collider
experiments is performed. The possibility to reduce radiative effects by
detection of hard photons is studied.


title:
Perturbative reliability of the Higgs-boson coupling in the standard
  electroweak model

abstract:
  We apply Pade summation to the \beta(\lambda) function for the quartic Higgs
coupling \lambda in the standard electroweak model. We use the \beta function
calculated to five loops in the minimal subtraction scheme to demonstrate the
improvement resulting from the summation, and then apply the method to the more
physical on-mass-shell renormalization scheme where \beta is known to three
loops. We conclude that the OMS \beta function and the running coupling
\lambda(\mu) are reliably known over the range of energies and Higgs-boson
masses of current interest.


title:
Experimental Tests of Factorization in Charmless Non-Leptonic Two-Body B
  Decays

abstract:
  Using a theoretical framework based on the next-to-leading order QCD-improved
effective Hamiltonian and a factorization Ansatz for the hadronic matrix
elements of the four-quark operators, we reassess branching fractions in
two-body non-leptonic decays $B \to PP, PV, VV$, involving the lowest lying
light pseudoscalar $(P)$ and vector $(V)$ mesons in the standard model. Using
the sensitivity of the decay rates on the effective number of colors, $N_c$, as
a criterion of theoretical predictivity, we classify all the current-current
(tree) and penguin transitions in five different classes. The recently measured
charmless two-body $B \to PP$ decays $(B^+ \to K^+ \eta^\prime, B^0 \to K^0
\eta^\prime, B^0 \to K^+\pi^-, B^+ \to \pi^+ K^0$ and charge conjugates) are
dominated by the $N_c$-stable QCD penguins (class-IV transitions) and their
estimates are consistent with data. The measured charmless $B \to PV$ $(B^+ \to
\omega K^+, ~B^+ \to \omega h^+)$ and $B\to VV$ transition $(B \to \phi K^*)$,
on the other hand, belong to the penguin (class-V) and tree (class-III)
transitions. The class-V penguin transitions are in general more difficult to
predict. We propose a number of tests of the factorization framework in terms
of the ratios of branching ratios for some selected $B \to h_1 h_2$ decays
involving light hadrons $h_1$ and $h_2$, which depend only moderately on the
form factors. We also propose a set of measurements to determine the effective
coefficients of the current-current and QCD penguin operators. The potential
impact of $B \to h_1 h_2$ decays on the CKM phenomenology is emphasized by
analyzing a number of decay rates in the factorization framework.


title: Exotic muon decays and the KARMEN anomaly

abstract:
  An anomaly in time distribution of neutrinos from the ISIS pulsed beam stop
source observed by the KARMEN collaboration is discussed. We show that the
anomaly can be interpreted as a superposition of two exponentials, both having
time constants consistent with the $\mu^{+}$ lifetime of 2.2 $\mu s$. % and,
therefore, It is assumed that they both originate from muon decays at rest.
  One of them describes the time distribution of the prompt neutrino events,
while the other describes the time distribution of events from delayed decays
of slowly moving ($\beta \simeq 0.02$) particles in the KARMEN calorimeter.
  We propose here that these particles are produced in exotic decays of
positive muons $\mu^{+}\to e^{+} + X$, resulting in the second exponential time
distribution shifted by the time of flight with respect to the time
distribution of neutrino events. This model gives an aceptable fit to the
KARMEN data if $X$ has a mass of 103.9 MeV.
  The possible decay modes of this new massive neutral particle are discussed.
This hypothesis can be experimentally tested in the near future by studying the
low energy part of the $e^{+}$ spectrum in the $\mu^{+}$ decays.


title:
The Supersymmetric Flavour and CP Problems From a Cosmological
  Perspective

abstract:
  The supersymmetric flavour and CP problems can be avoided if the first two
generations of sfermions are heavier than a few TeV and approximately
degenerate in mass. However using flavour and CP-violating constraints on the
third sfermion generation, together with the decoupling of the first two
generations, can dramatically affect cosmological predictions such as the relic
abundance of stable particles. In particular, we show that if the lightest
supersymmetric particle is essentially bino-like then requiring that all
flavour changing neutral current and CP-violating processes are adequately
suppressed, imposes severe limits on the bino mass, where typically
m_bino>(200-300) GeV. This leads to difficulties for models implementing the
scenario of heavy sfermion masses.


title:
A Direct Constraint on Dimension-Eight Operators from Z-->neutrino
  antinetrino gamma

abstract:
  We study the radiative decay Z-->neutrino antineutrino gamma whitin an
effective Lagrangian approach. Using the search for energetic single-photon
events in the data collected by the L3 collaboration, we get direct bounds on
the dimension-six and the dimension-eight operators associated with the
tau-neutrino magnetic moment and the anomalous electromagnetic properties of
the Z boson. As a by-product of our calculation, we reproduce the L3 result for
the bound on the tau-neutrino magnetic moment.


title: The Status of Neutrino Mass

abstract:
  New experimental results, if correct, require at least one light sterile
neutrino, in addition to the three active ones, to accommodate the mass
differences required to explain the solar $\nu_e$ deficit, the anomalous
$\nu/e$ ratio produced by atmospheric neutrinos, and either the candidate
events for $\nu_\mu\to\nu_e$ (or $\bar\nu_\mu\to\bar\nu_e$) from the LSND
experiment, or the possible need for a hot component of dark matter. This
neutrino mass pattern can not only accommodate all these four requirements, but
also provide a robust solution to a problem presently making heavy-element
synthesis by supernovae impossible and resolve a possible discrepancy between
big bang nucleosynthesis theory and observations.


title:
FCNC in leptonic and semileptonic decays of D mesons in a general
  two-Higgs doublet model

abstract:
  Large long-distance standard model effects in FCNC semileptonic D decays can
make observable these processes in future measurements. Eventual disagreements
in this sector and/or the observation of lepton family violating (LFV) D decays
would require an explanatio beyond the SM framework. In this paper we confront
present experimental data on leptonic and semileptonic FCNC and LFV D meson
decays with a version of the two-Higgs doublet model that allows these effects
to occur at tree- level. The stringent bounds on the parameters of the model
are obtained from D^0 --> l^+l'^- and D --> pi l^+l'^- decays. The consistency
of the model requires that the branching fractions of D --> V l^+l'^- decays
should be below the 10^{-9} level.


title:
Radiations from Oscillating Axionic Boson Stars in an External Magnetic
  Field

abstract:
  We solve numerically a field equation of axions coupled with gravity and show
solutions representing oscillating axionic boson stars with small mass $\sim
10^{-12}M_{\odot}$ and large radius $\sim 10^{8}$ cm. We present explicitly a
relation between the mass and the radius of the boson stars with such a small
mass. These axionic boson stars are shown to possess oscillating electric
currents in an external magnetic field and to radiate electromagnetic fields
with a frequency given by mass of the axions. We estimate the luminosity of the
radiation in a strong magnetic field $10^{12}$G of neutron stars, typically
$\sim 10^{24}$ erg/s with the axion mass being $10^{-5}$eV.


title:
Finite coherent length and multi-pion correlation effects on two-pion
  interferometry

abstract:
  The effects of multi-pion correlations and finite coherent length on two-pion
interferometry are studied. It was shown that as the pion multiplicity and
coherent length become larger, the apparent radius and the apparent coherent
parameters derived from two-pion interferometry become smaller. The influence
of the coherent length on the effective temperature is discussed.


title: Spontaneous R-Parity Violation and Electroweak Baryogenesis

abstract:
  The possibility of baryogenesis at the electroweak phase transition is
considered within the context of a minimal supersymmetric standard model with
spontaneous R-parity violation. Provided that at least one of the sneutrino
fields acquires a large enough vacuum expectation value, a sufficient baryon
asymmetry can be created. Compared to R-parity conserving models the choice of
soft supersymmetry breaking parameters is less restricted. The observed baryon
asymmetry, n_B/s ~ 10^(-10), can be explained by this scenario and the produced
baryon-to-entropy ratio may easily be as high as n_B/s ~ 10^(-9).


title:
Influence of the left-handed part of the neutrino mass matrix on the
  lepton number violating e-e- -> W-W- process

abstract:
  Influence of the neutrino mass submatrix $M_L$ on the e-e- -> W-W- process is
discussed. Taking into account various possible CP signatures of heavy
neutrinos it is shown that, in some cases, nonzero $M_L$ substantially changes
predictions for maximum possible values of the e-e- -> W-W- cross section. A
direct role of the $\omega^2$ parameter (coming from neutrinoless double beta
decay) is clarified. The consequences of doubly charged Higgs particles
$\delta^{--}$ with resonances even far away from energies of the future linear
lepton collider ($\sqrt{s}=0.5-1$ TeV) are studied.


title:
Transition from Photoproduction to Deep-Inelastic Scattering in
  Jetproduction at HERA in NLO QCD

abstract:
  We present results from NLO QCD calculations on the production of jets in ep
collisions at HERA in a continuous range of photon virtuality Q^2. Special
attention is given to the collinear singularities from the virtual photon and
the resolved virtual photon component of the cross sections. Comparisons with
dijet data from H1 are shown and the infrared sensitivity of dijet cross
sections is discussed.


title: Towards a superformula for neutrinoless double beta decay

abstract:
  A general Lorentz--invariant parameterization for the long-range part of the
$0\nu\beta\beta$ decay rate is derived. Combined with the short range part this
general parameterization in terms of effective $B-L$ violating couplings will
allow it to extract the $0\nu\beta\beta$ limits on arbitrary lepton number
violating theories. Several new nuclear matrix elements appear in the general
formalism compared to the standard neutrino mass mechanism. Some of these new
matrix elements have never been considered before and are calculated within
pn-QRPA. Using these, limits on lepton number violating parameters are derived
from experimental data on $^{76}$Ge.


title: Light propagation in non-trivial QED vacua

abstract:
  Within the framework of effective action QED, we derive the light cone
condition for homogeneous non-trivial QED vacua in the geometric optics
approximation. Our result generalizes the ``unified formula'' suggested by
Latorre, Pascual and Tarrach and allows for the calculation of velocity shifts
and refractive indices for soft photons travelling through these vacua.
Furthermore, we clarify the connection between the light velocity shift and the
scale anomaly. This study motivates the introduction of a so-called effective
action charge that characterizes the velocity modifying properties of the
vacuum. Several applications are given concerning vacuum modifications caused
by, e.g., strong fields, Casimir systems and high temperature.