title: The Search for Anomalous W^+ W^- t \bar{t} Couplings at the LC

abstract:
  We study production of t \bar{t} via W^+ W^--fusion, including the relevant
backgrounds at the proposed Linear Collider (an e^+ e^- collider with \sqrt{S}
= 1.5 TeV) in the context of a Higssless Standard Model (HSM), i.e. a nonlinear
SU(2)_L \times U(1)_Y chiral Lagrangian, including dimension five W^+ W^- t
\bar{t} interactions. Deviation from the HSM predictions can be used to
constrain the coefficients of these operators to an order of 10^-1 (divided by
the cut-off scale \Lambda = 3.1 TeV) with a 95% C.L..


title:
Theoretical Challenges for a Precision Measurement of the W Mass at
  Hadron Colliders

abstract:
  We summarize the status of calculations of the electroweak radiative
corrections to W and Z boson production via the Drell-Yan mechanism at hadron
colliders. To fully exploit the precision physics potential of the
high-luminosity environment of the Fermilab Tevatron p \bar p (Run II) and the
CERN LHC p p colliders, it is crucial that the theoretical predictions are well
under control. The envisioned precision physics program includes a precise
measurement of the W boson mass and the (leptonic) weak mixing angle, as well
as probing the Standard Model (SM) of electroweak interactions at the highest
accessible center-of-mass energies. Some numerical results are presented.


title:
Effective String Theory of Vortices and Regge Trajectories of Hybrid
  Mesons with Zero Mass Quarks

abstract:
  We show how a field theory containing classical vortex solutions can be
expressed as an effective string theory of long distance QCD describing the two
transverse oscillations of the string. We use the semiclassical expansion of
this effective string theory about a classical rotating string solution to
obtain Regge trajectories for mesons with zero mass quarks. The first
semiclassical correction adds the constant 1/12 to the classical Regge formula
for the angular momentum of mesons on the leading Regge trajectory. In D
spacetime dimensions, this additive constant is (D-2)/24. The excited states of
the rotating string give rise to daughter Regge trajectories determining the
spectrum of hybrid mesons.


title: Potential Models for Radiative Rare B Decays

abstract:
  We compute the branching ratios for the radiative rare decays of B into
K-Meson states and compare them to the experimentally determined branching
ratio for inclusive decay b -> s gamma using non relativistic quark model, and
form factor definitions consistent with HQET covariant trace formalism. Such
calculations necessarily involve a potential model. In order to test the
sensitivity of calculations to potential models we have used three different
potentials, namely linear potential, screening confining potential and heavy
quark potential as it stands in QCD.We find the branching ratios relative to
the inclusive b ->s gamma decay to be (16.07\pm 5.2)% for B -> K^* (892)gamma
and (7.25\pm 3.2)% for B -> K_2^* (1430)gamma for linear potential. In the case
of the screening confining potential these values are (19.75\pm 5.3)% and
(4.74\pm 1.2)% while those for the heavy quark potential are (11.18\pm 4.6)%
and (5.09\pm 2.7)% respectively. All these values are consistent with the
corresponding present CLEO experimental values: (16.25\pm 1.21)% and (5.93\pm
0.46)%.


title: Off-shell W-pair production - universal versus non-universal corrections

abstract:
  Electroweak radiative corrections to e+e- scattering processes typically
amount to O(10%) at LEP energies. Their logarithmic increase with energy
renders them even more important at future colliders. Although the bulk of
these corrections is due to universal process-independent effects, the
remaining non-universal corrections are nevertheless phenomenologically
important. We describe the structure of the universal corrections to e+e- -->
WW --> 4f in detail and discuss the numerical size of universal and
non-universal effects using the Monte Carlo generator RACOONWW.


title: Charge fluctuations in a final state with QGP

abstract:
  Charge fluctuations as a possible signal of quark - gluon plasma (QGP) were
recently suggested. A short summary of comments presented on this subject is
given and supplemented by a discussion of the coexistence of pions produced
"directly" and through a QGP phase. Such a coexistence may obscure the expected
plasma signal similarly to the effects considered in the comments mentioned
above.


title: CP violation, the CKM matrix and New Physics

abstract:
  Loop corrections for physics beyond the Standard Model are computed. DWe
discuss the influence of new physics on CP-violating observables. Assuming the
standard model gives a correct description of tree level processes, we show how
a consistent procedure can determine the parameters of the standard model and
check its validity also in loop induced processes. A method to include new
physics in a systematic way is sketched.


title: Two-loop electroweak contributions to $\Delta r$

abstract:
  A review is given on the quantum correction $\Delta r$ in the $W$--$Z$ mass
correlation at the electroweak two-loop level, as derived from the calculation
of the muon lifetime in the Standard Model. Exact results for $\Delta r$ and
the $W$-mass prediction including ${\mathcal{O}}(\alpha^2)$ corrections with
fermion loops are presented and compared with previous results of a
next-to-leading order expansion in the top-quark mass.


title:
Precision Predictions for (Un)Stable WW/4f Production in e +e-
  Annihilation: YFSWW3/KoralW-1.42/YFSZZ

abstract:
  We present precision calculations of the processes e+ e- -> 4-fermions in
which the double resonant W+ W- and ZZ intermediate states occur. Referring to
these latter intermediate states as the 'signal processes', we show that, by
using the YFS Monte Carlo event generators YFSWW3-1.14 and KoralW-1.42 in an
appropriate combination, we achieve a physical precision on the WW signal
process, as isolated with LEP2 MC Workshop cuts, below 0.5 per cent. We stress
the full gauge invariance of our calculations and we compare our results with
those of other authors where appropriate. In particular, sample Monte Carlo
data are explicitly illustrated and compared with the results of the program
RacoonWW of Denner et al. In this way, we cross check that the total (physical
oplus technical) precision tag for the WW signal process cross section is 0.4
per cent for 200 GeV, for example. Results are also given for 500 GeV with an
eye toward the LC. For the analogous ZZ case, we cross check that our YFSZZ
calculation yields a total precision tag of 2 per cent, when it is compared to
the results of ZZTO and GENTLE of Passarino and Bardin et al., respectively.


title: Testing Higgs Self-Couplings at High-Energy Linear Colliders

abstract:
  In order to verify the Higgs mechanism experimentally, the Higgs
self-couplings have to be probed. These couplings allow the reconstruction of
the characteristic Higgs potential responsible for the electroweak symmetry
breaking. The couplings are accessible in a variety of multiple Higgs
production processes. The theoretical analysis including the most relevant
channels for the production of neutral Higgs boson pairs at high-energy and
high-luminosity $e^+e^-$ linear colliders will be presented in this note.


title: Production of MSSM Higgs Bosons at Future $\gamma\gamma$ Colliders

abstract:
  Future $\gamma\gamma$ colliders allow the production of the heavy neutral
MSSM Higgs bosons $H$ and $A$ as single resonances. The prospects of finding
these particles in the $b\bar{b}$ and the neutralino-pair final states have
been analysed. The $H,A$ bosons can be discovered for medium values of
$\tan\beta$ with masses up to 70--80% of the initial $e^\pm e^-$ c.m. energy.
This production mode thus covers parts of the supersymmetric parameter space
that are not accessible at other colliders.


title: An introduction to CHPT

abstract:
  These lectures provide an elementary introduction to Chiral Perturbation
Theory, focused on the sector of pseudoscalar meson interactions. Basic
concepts and technical methods of this approach are discussed on general
grounds and with the help of a few specific examples.


title: Optimization of symbolic evaluation of helicity amplitudes

abstract:
  We present a method for symbolic evaluation of Feynman amplitudes. We
construct special polarization basis for spinor particles which produces
compact expressions for tensor products of basis spinors.


title: Light Charged Higgs Boson and Supersymmetry

abstract:
  A possible discovery of a relatively light charged Higgs boson H^+ in near
future experiments, with a mass M_{H+} ~< 110 GeV, together with the present
LEP2 direct limits on the chargino and neutral Higgs sectors, would disfavour
the minimal supersymmetric standard model as well as its frequently discussed
next-to-minimal supersymmetric extension. We show that a supersymmetric origin
can naturally be ascribed to the existence of such a light charged Higgs scalar
within the context of the recently introduced minimal nonminimal supersymmetric
standard model.


title: Effective field theory and the quark model

abstract:
  We analyze the connections between the quark model (QM) and the description
of hadrons in the low-momentum limit of heavy-baryon effective field theory in
QCD. By using a three-flavor-index representation for the effective baryon
fields, we show that the ``nonrelativistic'' constituent QM for baryon masses
and moments is completely equivalent through O(m_s) to a parametrization of the
relativistic field theory in a general spin--flavor basis. The flavor and spin
variables can be identified with those of effective valence quarks. Conversely,
the spin-flavor description clarifies the structure and dynamical
interpretation of the chiral expansion in effective field theory, and provides
a direct connection between the field theory and the semirelativistic models
for hadrons used in successful dynamical calculations. This allows dynamical
information to be incorporated directly into the chiral expansion. We find, for
example, that the striking success of the additive QM for baryon magnetic
moments is a consequence of the relative smallness of the non-additive
spin-dependent corrections.


title: Predictions for e+ e- -> WW -> 4f(gamma) at a future linear collider

abstract:
  We describe the salient features of precise predictions for the processes e+
e- -> WW -> 4f(gamma) as obtained with the Monte Carlo generator RacoonWW,
including the complete O(alpha) electroweak radiative corrections in the
double-pole approximation. Numerical results for some distributions are given
at the typical linear-collider energy \sqrt{s}=500 GeV. Moreover, we study the
impact of the non-universal electroweak corrections by comparing with results
of an improved Born approximation.


title:
The Instanton/Sphaleron Mechanism of Prompt Gluon Production in High
  Energy Heavy Ion Collisions at RHIC

abstract:
  We argue that if the growing part of hadron-hadron cross section (described
phenomenologically by the supercritical soft Pomeron) is due to
instanton/sphaleron mechanism, one should find certain qualitative features of
the produced cluster which differ from the usual string fragmentation.
Furthermore, we suggest that this mechanism should be even more important for
heavy ion collisions in the RHIC energy domain. Large number of parton-parton
collisions should result in hundreds of produced sphaleron-like gluomagnetic
clusters per unit rapidity. Unlike perturbative gluons (or mini-jets), these
{\em classically unstable} objects promptly decay into several gluons and
quarks in mini-explosions, leading to very rapid entropy generation. This may
help to explain why the QGP seem to be produced at RHIC so early. We further
argue that this mechanism cannot be important at higher energies (LHC), where
perturbative description should apply.


title: Lectures on Cosmic Topological Defects

abstract:
  These lectures review certain topological defects and aspects of their
cosmology. Unconventional material includes brief descriptions of electroweak
defects, the structure of domain walls in non-Abelian theories, and the
spectrum of magnetic monopoles in SU(5) Grand Unified theory.


title:
Bound q bar q systems in the framework of different versions of 3D
  reductions of the Bethe-Salpeter equation

abstract:
  Five different versions of the three-dimensional (3D) reduction of the
Bethe-Salpeter (BS) equation in the instantaneous approximation for kernel of
BS equation for the two-fermion systems are formulated. The normalization
condition for the bound-state wave function in all versions are derived.
Further, the 3D reduction of BS equation without instantaneous approximation
for the kernel of BS equation is formulated in the quasi-potential approach.
Except of the Salpeter version, other four versions have the correct one-body
limit (Dirac equation) when mass of one of constituent fermions tends to
infinity. Application of these versions for investigation of the different
properties of the q bar q bound systems are considered.


title:
Single superparticle production via $\gamma\gamma$ collision with
  explicit R-parity violation

abstract:
  We study the single production of scalar neutrinos or charginos via
$\gamma\gamma$ collision in an R-parity ($R_{p}$) violating supersymmetric
model. It may be possible to detect a sneutrino or a chargino at a Linear
Collider (LC) in $\gamma \gamma$ operation mode, as a test of supersymmetry and
$R_p$-violation. Because of the clean background in LC, stringent constraints
on $R_p$ violating parameters can be obtained even if the process cannot be
observed at the future Linear Collider.


title: MSW mediated neutrino decay and the solar neutrino problem

abstract:
  We investigate the solar neutrino problem assuming simultaneous presence of
MSW transitions in the sun and neutrino decay on the way from sun to earth. We
do a global $\chi^2$-analysis of the data on total rates in Cl, Ga and
Superkamiokande (SK) experiments and the SK day-night spectrum data and
determine the changes in the allowed region in the $\dm - \tan^2\theta$ plane
in presence of decay. We also discuss the implications for unstable neutrinos
in the SNO experiment.


title:
Gauge Invariant Classes of Feynman Diagrams and Applications for
  Calculations

abstract:
  In theories like SM or MSSM with a complex gauge group structure the complete
set of Feynman diagrams contributed to a particular physics process can be
splited to exact gauge invariant subsets. Arguments and examples given in the
review demonstrate that in many cases computations and analysis of the gauge
invariant subsets are important.


title: Nonlinear evolution and saturation for heavy nuclei in DIS

abstract:
  The nonlinear evolution equation for the scattering amplitude of colour
dipole off the heavy nucleus is solved in the double logarithmic approximation.
It is found that if the initial parton density in a nucleus is smaller then
some critical value, then the scattering amplitude is a function of one scaling
variable inside the saturation region, whereas if it is greater then the
critical value, then the scaling behaviour breaks down. Dependence of the
saturation scale on the number of nucleons is discussed as well.


title: General Analysis of New Physics in $B\to J/\psi K$

abstract:
  We present a model-independent parametrization of the $B^\pm\to J/\psi
K^\pm$, $B_d\to J/\psi K_S$ decay amplitudes by taking into account the
constraints that are implied by the isospin symmetry of strong interactions.
Employing estimates borrowed from effective field theory, we explore the impact
of physics beyond the Standard Model and introduce -- in addition to the usual
mixing-induced CP asymmetry $A_{CP}^{mix}$ in $B_d\to J/\psi K_S$ -- a set of
three observables, allowing a general analysis of possible new-physics effects
in the $B\to J/\psi K$ system. Imposing a dynamical hierarchy of amplitudes, we
argue that one of these observables may already be accessible at the
first-generation $B$-factories, whereas the remaining ones will probably be
left for second-generation $B$ experiments. However, in the presence of large
rescattering effects, all three new-physics observables may be sizeable. We
also emphasize that a small value of $A_{CP}^{mix}$ could be due to new-physics
effects arising at the $B\to J/\psi K$ decay-amplitude level. In order to
establish such a scenario, the observables introduced in this paper play a key
role.


title:
Transverse Spin Asymmetries in Drell-Yan Processes: $\mathbf
  p^{\uparrow} p \to \mu^+ \mu^- X$}

abstract:
  We consider two different spin asymmetries in Drell-Yan processes generated
by the collisions of an unpolarized proton beam on transversely polarized
protons: the muon helicity asymmetry and the left-right asymmetry. We calculate
the asymmetries in the framework of the QCD improved parton model, taking into
account the parton transverse momentum and considering the first order QCD
corrections. The muon helicity asymmetry is sensitive to the quark transversity
distribution and is nonvanishing even at zero order. On the contrary the
left-right asymmetry vanishes at zero order but not at first order in the QCD
coupling constant, as a result of gluon contribution.


title:
Cartography with Accelerators: Locating Fermions in Extra Dimensions at
  Future Lepton Colliders

abstract:
  In the model of Arkani-Hamed and Schmaltz the various chiral fermions of the
Standard Model(SM) are localized at different points on a thick wall which
forms an extra dimension. Such a scenario provides a way of understanding the
absence of proton decay and the fermion mass hierarchy in models with extra
dimensions. In this paper we explore the capability of future lepton colliders
to determine the location of these fermions in the extra dimension through
precision measurements of conventional scattering processes both below and on
top of the lowest lying Kaluza-Klein gauge boson resonance. We show that for
some classes of models the locations of these fermions can be very precisely
determined while in others only their relative positions can be well measured.


title: Soft pion theorem for hard near threshold pion production

abstract:
  We prove new soft pion theorem for the near threshold pion production by a
hard electromagnetic probe. This theorem relates various near threshold pion
production amplitudes to the nucleon distribution amplitudes. The new soft pion
theorem is in a good agreement with the SLAC data for F_2^p(W,Q^2) for W^2 <
1.4 GeV^2 and 7 < Q^2 < 30.7 GeV^2.


title: SPIN - Progress and Prospects

abstract:
  I review the progress in fundamental spin physics over the past several years
and the prospects for the future. The progress is striking and the prospects
are excellent.


title:
Gauge Fields Out-Of-Equilibrium: A Gauge Invariant Formulation and the
  Coulomb Gauge

abstract:
  We study the abelian Higgs model out-of-equilibrium in two different
approaches, a gauge invariant formulation, proposed by Boyanovsky et al.
\cite{Boyanovsky:1996dc} and in the Coulomb gauge. We show that both approaches
become equivalent in a consistent one loop approximation. Furthermore, we carry
out a proper renormalization for the model in order to prepare the equations
for a numerical implementation. The additional degrees of freedom, which arise
in gauge theories, influence the behavior of the system dramatically. A
comparison with results in the 't Hooft-Feynman background gauge found by us
recently, shows very good agreement.


title: Probing the Geometry of the Universe at the NLC

abstract:
  The hierarchy problem in particle physics has recently been approached from a
geometric point of view in different models. These approaches postulate the
existence of extra dimensions with various geometric properties, to explain how
the hierarchy between the apparent scale of gravity ${\bar M}_P \sim 10^{18}$
GeV and the weak scale $m_W \sim 100$ GeV can be generated. Generally, these
models predict that the effects of gravity mediated interactions become strong
at the weak scale. This fact makes the NLC a promising tool for testing such
extra dimensional models.


title:
The Fermion Boson Interaction Within the Linear Sigma Model at Finite
  Temperature

abstract:
  We reinvestigate the interaction of massless fermions with massless bosons at
finite temperature. Specifically, we calculate the self-energy of massless
fermions due the interaction with massless bosons at high temperature, which is
the region where thermal effects are maximal. The calculations are concentrated
in the limit of vanishing fermion three momentum and after considering the
effective fermion and boson dressed masses, we obtain the damping rate of the
fermion up to order $g^3$. It is shown that in the limit $k_0 \ll T$ the
fermion acquire a thermal mass of order $gT$ and the leading term of the
fermion damping rate is of order $g^2T+g^3T$.


title:
Gauge-boson propagator in out of equilibrium quantum-field system and
  the Boltzmann equation

abstract:
  We construct from first principles a perturbative framework for studying
nonequilibrium quantum-field systems that include gauge bosons. The system of
our concern is quasiuniform system near equilibrium or nonequilibrium
quasistationary system. We employ the closed-time-path formalism and use the
so-called gradient approximation. No further approximation is introduced. We
construct a gauge-boson propagator, with which a well-defined perturbative
framework is formulated. In the course of construction of the framework, we
obtain the generalized Boltzmann equation (GBE) that describes the evolution of
the number-density functions of gauge-bosonic quasiparticles. The framework
allows us to compute the reaction rate for any process taking place in the
system. Various processes, in turn, cause an evolution of the systems, which is
described by the GBE.


title:
Pseudoscalar production in electromagnetic fields by a Schwinger-like
  mechanism

abstract:
  In this talk I report on some recent calculations on the production of
pseudoscalars from intense electromagnetic fields.


title: Reentrant violation of special relativity in the low-energy corner

abstract:
  In the effective relativistic quantum field theories the energy region, where
the special relativity holds, can be sandwiched from both the high and low
energies sides by domains where the special relativity is violated. An example
is provided by 3He-A where the relativistic quantum field theory emerges as the
effective theory. The reentrant violation of the special relativity in the
ultralow energy corner is accompanied by the redistribution of the
momentum-space topological charges between the fermionic flavors. At this
ultralow energy an exotic massless fermion with the topological charge $N_3=2$
arises, whose energy spectrum mixes the classical and relativistic behavior.
This effect can lead to neutrino oscillations if neutrino flavors are still
massless at this energy scale.


title: Glueballs, hybrid and exotic mesons

abstract:
  We review lattice QCD results for glueballs (including a discussion of mixing
with scalar mesons), hybrid mesons and exotic mesons (such as $B_s B_s$
molecules).


title:
Thermal ratio of the disorder deviation and the space-time deconfined
  phase size

abstract:
  A systematic study of the strongly interacting matter under extreme
conditions via the form of the thermal ratio of the disorder deviation is
presented. The evolution of fermi- and bose- particles (quarks and gluons) is
studied in the framework of multi-particle correlation and distribution
functions to predict the size of the finite-temperature deconfined phase.


title:
Thermodynamics of the 3-flavor NJL model : chiral symmetry breaking and
  color superconductivity

abstract:
  Employing an extended three flavor version of the NJL model we discuss in
detail the phase diagram of quark matter. The presence of quark as well as of
diquark condensates gives raise to a rich structure of the phase diagram. We
study in detail the chiral phase transition and the color superconductivity as
well as color flavor locking as a function of the temperature and chemical
potentials of the system.


title:
Comment on "Subleading Corrections to Parity Violating Pion
  Photoproduction"

abstract:
  In a recent preprint, hep-ph/0012253, Zhu et al. calculated a part of the
next-to-leading order corrections to parity-violating pion photoproduction
(pol)gamma p-> pi^+ n in heavy-baryon chiral perturbation theory. They claim
they have found the contribution as large as the leading-order. If correct, the
process will not be a clean way to extract the longest range PV pion-nucleon
coupling constant h_{\pi NN}^(1), as was asserted in our previous publications
(hep-ph/0011230, nucl-th/0011100). In this comment we show that there is no
solid evidence to support Zhu et al.'s claim. Moreover, we show that the
subleading parity-violating coupling h_V cannot be extracted from observables
at the order of interest based on the formalism of effective field theory.


title: NonQCD contributions to heavy quark masses and sensitivity to Higgs mass

abstract:
  We find that if the Higgs mass is close to its present experimental lower
limit (100 GeV),Yukawa interactions in the quark-Higgs sector can make
substantial contributions to the heavy quark MS masses.


title:
Charmless Hadronic Decays of B Mesons to a Pseudoscalar and a Tensor
  Meson

abstract:
  We study two-body charmless hadronic decays of $B$ mesons to a pseudoscalar
meson ($P$) and a tensor meson ($T$) in the frameworks of both flavor SU(3)
symmetry and generalized factorization. Certain ways to test validity of the
generalized factorization are proposed, based on the flavor SU(3) analysis. We
present a set of relations between a flavor SU(3) amplitude and a corresponding
amplitude in the generalized factorization which bridge both approaches in $B
\to PT$ decays. The branching ratios and CP asymmetries are calculated using
the \emph{full} effective Hamiltonian including all the \emph{penguin}
operators and the form factors obtained in the non-relativistic quark model of
Isgur, Scora, Grinstein and Wise. We identify the decay modes in which the
branching ratios and CP asymmetries are expected to be relatively large.


title:
A relation between the charge radii of \pi^{+},\K^{+},K^{o} derived by
  the general QCD parametrization

abstract:
  We derive,using the general QCD parametrization,the approximate relation
r^{2}(\pi^{+}) - r^{2}(K^(+)) approximately equal to -r^{2}(K^(o), where the
r's are the charge radii.The relation is satisfied but the experimental errors
are still sizeable.The derivation is similar to (but even simpler than) that
for r^{2}(p) -r^{2}(n) approximately equal to r^{2}({\Delta})[Phys.Lett.B
448,107 (1999)].


title: FCNC top quark decays beyond the Standard Model

abstract:
  Flavor Changing Neutral Current decays of the top quark within the strict
context of the Standard Model are known to be extremely rare. In fact, they are
hopelessly undetectable at the Tevatron, LHC and LC in any of their scheduled
upgradings. Therefore, if a few of these events eventually show up in the
future we will have certainly discovered new physics. We argue that this could
well be the case for the LHC and the LC both within the Minimal Supersymmetric
Standard Model (MSSM) and in a general two-Higgs-doublet model (2HDM),
especially if we look for FCNC top quark decays into Higgs bosons.


title: 12 Years of Precision Calculations for LEP. What's Next?

abstract:
  I shortly review time period of twelve years, 1989-2000, which was devoted to
a theoretical support of experiments at LEP and SLC at Z resonance and discuss
several directions of possible future work in the field of precision
theoretical calculations for experiments at future colliders.


title: A Systematic Approach to Anomalous Phenomena at High Energies

abstract:
  In one-dimensional case the search for presence of the anomalous phenomena in
multiplicity distributions is usually performed in frame of the horizontal,
vertical and mixed types of the analysis. We show that if the data involve a
d-dimensional phase space, there exists a convenient procedure, generalizing
the one-dimensional approach, which allows to introduce more non-trivial types
of the analysis; we formulate them in some detail in one-, two-, and partially
also in three-dimensions.


title:
Bilocal expansion of the Borel amplitude and the hadronic tau decay
  width

abstract:
  The singular part of Borel transform of a QCD amplitude near the infrared
renormalon can be expanded in terms of higher order Wilson coefficients of the
operators associated with the renormalon. In this paper we observe that this
expansion gives nontrivial constraints on the Borel amplitude that can be used
to improve the accuracy of the ordinary perturbative expansion of the Borel
amplitude. In particular, we consider the Borel transform of the Adler function
and its expansion around the first infrared renormalon due to the gluon
condensate. Using the next-to-leading order Wilson coefficient of the gluon
condensate operator, we obtain an exact constraint on the Borel amplitude at
the first IR renormalon. We then extrapolate, using judiciously chosen
conformal transformations and Pade approximants, the ordinary perturbative
expansion of the Borel amplitude in such a way that this constraint is
satisfied. This procedure allows us to predict the $O(\alpha_s^4)$ coefficient
of the Adler function, which gives a result consistent with the estimate by
Kataev and Starshenko using a completely different method. We then apply this
improved Borel amplitude to the tau decay width, and obtain the strong coupling
constant $\alpha_s(M_Z) =0.1193 \pm 0.0007_{exp.} \pm 0.0010_{EW+CKM} \pm
0.0009_{meth.} \pm 0.0003_{evol.}$. We then compare this result with those of
other resummation methods.


title: Further search for a neutral boson with a mass around 9 MeV/c2

abstract:
  Two dedicated experiments on internal pair conversion (IPC) of isoscalar M1
transitions were carried out in order to test a 9 MeV/c2 X-boson scenario. In
the 7Li(p,e+e-)8Be reaction at 1.1 MeV proton energy to the predominantly T=0
level at 18.15 MeV, a significant deviation from IPC was observed at large pair
correlation angles. In the 11B(d,n e+e-)12C reaction at 1.6 MeV, leading to the
12.71 MeV 1+ level with pure T=0 character, an anomaly was observed at 9
MeV/c2. The compatibility of the results with the scenario is discussed.


title: Precision Physics Near LEP Shutdown and Evolutionary Developments

abstract:
  The most celebrated aspects of precision physics are briefly summarized. New
ideas are also introduced that may lead to further developments in the field of
radiative corrections, with special emphasis to multi-loop numerical evaluation
and to a correct treatment of QED radiation for arbitrary processes.


title: Transversity distributions in the nucleon in the large-N_c limit

abstract:
  We compute the quark and antiquark transversity distributions in the nucleon
at a low normalization point of 600 MeV in the large-$N_c$ limit, where the
nucleon can be described as a soliton of an effective chiral theory (chiral
quark-soliton model). The flavor-nonsinglet distributions, $\delta u(x) -
\delta d(x)$ and $\delta\bar u(x) - \delta\bar d(x)$, appear in leading order
of the $1/N_c$-expansion, while the flavor-singlet distributions, $\delta u(x)
+ \delta d(x)$ and $\delta\bar u(x) + \delta\bar d(x)$, are non-zero only in
next-to-leading order. The transversity quark and antiquark distributions are
found to be significantly different from the longitudinally polarized
distributions $\Delta u (x) \pm \Delta d (x)$ and $\Delta\bar u (x) \pm
\Delta\bar d (x)$, respectively, in contrast to the prediction of the naive
non-relativistic quark model. We show that this affects the predictions for the
spin asymmetries in Drell-Yan pair production in transversely polarized pp and
ppbar collisions.


title: Exclusive weak B decays to excited meson states

abstract:
  Exclusive semileptonic B decays to radially excited charmed mesons and rare
radiative B decay to the orbitally excited tensor K_2^*(1430) meson are
investigated in the framework of the relativistic quark model based on the
quasipotential approach in quantum field theory. The heavy quark expansion is
applied for the semileptonic B\to D^{(*)}'e\nu decays. Both relativistic and
the 1/m_Q corrections are found to play an important role for these decays and
substantially modify results. For rare radiative B -> K_2^*(1430)\gamma decay
such an expansion is not used for the s quark. Instead we apply the expansion
in inverse powers of large recoil momentum of final K_2^*(1430) meson. The
calculated branching fraction BR(B -> K_2^*(1430)\gamma)=(1.7\pm 0.6)\times
10^{-5} as well as the ratio BR(B -> K_2^*(1430)\gamma)/BR(B ->
K^*(892)\gamma)=0.38\pm 0.08 are found to be in a good agreement with recent
experimental data from CLEO.


title: Testing Landau gauge OPE on the Lattice with a $<A^2>$ Condensate

abstract:
  Using the operator product expansion we show that the $O(1/p^2)$ correction
to the perturbative expressions for the gluon propagator and the strong
coupling constant resulting from lattice simulations in the Landau gauge are
due to a non-vanishing vacuum expectation value of the operator $A^\mu A_\mu$.
This is done using the recently published Wilson coefficients of the identity
operator computed to third order, and the subdominant Wilson coefficient
computed in this paper to the leading logarithm. As a test of the applicability
of OPE we compare the $<A^\mu A_\mu>$ estimated from the gluon propagator and
the one from the coupling constant in the flavourless case. Both agree within
the statistical uncertainty: $\sqrt{< A^\mu A_\mu >} \simeq 1.64(15)$ GeV.
Simultaneously we fit $\Lams = $ 233(28) MeV in perfect agreement with previous
lattice estimates. When the leading coefficients are only expanded to two
loops, the two estimates of the condensate differ drastically. As a consequence
we insist that OPE can be applied in predicting physical quantities only if the
Wilson coefficients are computed to a high enough perturbative order.


title: Use of Lambda_b Polarimetry in Top Quark Spin-Correlation Functions

abstract:
  Due to the absence of hadronization effects and the large top mass, top quark
decay will be uniquely sensitive to fundamental electroweak physics at the
Tevatron, at the LHC, and at a future linear collider. A complete measurement
of the four helicity amplitudes in top decay is possible by the combined use of
Lambda_b and W polarimetry in stage-two spin-correlation functions (S2SC). In
this paper, the most general Lorentz-invariant decay density matrix is obtained
for the decay sequence (t --> W b) where (b --> l nu c) and (W --> l nu), and
likewise for the CP-conjugate mode. These density matrices are expressed in
terms of b-polarimetry helicity parameters which enable a unique determination
of the relative phases among the helicity amplitudes. Thereby, S2SC
distributions and single-sided b-W-interference distributions are expressed in
terms of these parameters. The four b-polarimetry helicity parameters involving
the A(-1,-1/2) amplitude are considered in detail. Lambda_b polarimetry
signatures will not be suppressed in top quark analyses when the final
neutrino's angles-and-energy variables are used for (b --> l nu c).


title: Two-loop QCD corrections to massless quark-gluon scattering

abstract:
  We present the O(alphas^4) virtual QCD corrections to the scattering process
of massless quark qqbar -> gg due to the interference of tree and two-loop
amplitudes and to the self-interference of one-loop amplitudes. We work in
conventional dimensional regularisation and our results are renormalised in the
MSbar scheme. The structure of the infrared divergences agrees with that
predicted by Catani while expressions for the finite remainder are given for
the qqbar -> gg and the qg -> qg (gqbar -> gqbar) scattering processes in terms
of logarithms and polylogarithms that are real in the physical region. These
results, together with those previously obtained for quark-quark scattering,
are important ingredients in the next-to-next-to-leading order contribution to
inclusive jet production at hadron colliders.


title: Quarkonium Spectroscopy and Perturbative QCD: A New Perspective

abstract:
  We study the energy spectrum of bottomonium in perturbative QCD, taking
alpha_s(Mz)=0.1181 +/- 0.0020 as input and fixing m_b^{MSbar}(m_b^{MSbar}) on
the Upsilon(1S) mass. Contrary to wide beliefs, perturbative QCD reproduces
reasonably well the gross structure of the spectrum as long as the coupling
constant remains smaller than one. We perform a detailed analysis and discuss
the size of non-perturbative effects. A new qualitative picture on the
structure of the bottomonium spectrum is provided. The lowest-lying (c,cbar)
and (b,cbar) states are also examined.


title:
Constraints on non-Newtonian gravity from the Casimir force measurements
  between two crossed cylinders

abstract:
  Constraints on the Yukawa-type corrections to Newtonian gravitational law are
obtained resulting from the measurement of the Casimir force between two
crossed cylinders. The new constraints are stronger than those previously
derived in the interaction range between 1.5 nm and 11 nm. The maximal
strengthening in 300 times is achieved at 4.26 nm. Possible applications of the
obtained results to the elementary particle physics are discussed.


title: Baryogenesis via lepton number violation in Anti-GUT model

abstract:
  We study the baryogenesis via lepton number violation in the model of
Anti-GUT. The origin of the baryogenesis is the existence of right-handed
Majorana neutrinos which decay in a C, CP and lepton number violation way. The
baryon number asymmetry is calculated in the extended Anti-GUT model which is
only able to predict order of magnitude-wise. We predicted baryon number to
entropy ratio, Y_B=1.46{+5.87\atop-1.17}\times10^{-11}, and this result agrees
with experimental values very well.


title: Magnetic Field Induced Gap and Kink Behavior of Thermal Conductivity

abstract:
  The thermal conductivity of a quasiparticle (QP) system described by a
relativistic four-fermion interaction model in the presence of an external
magnetic field is calculated. It is shown that, for narrow width of
quasiparticles, the thermal conductivity, as a function of the applied magnetic
field, exhibits a kink behavior at a critical field $B_{c}\sim T^{2}$. The kink
is due to the opening of a gap in the QP spectrum at a critical magnetic field
$B_c$ and to the enhancement of the transitions between the zeroth and first
Landau levels. Possible applications of the results are discussed.


title:
High-temperature, classical, real-time dynamics of non-abelian gauge
  theories as seen by a computer

abstract:
  We test at the electroweak scale the recently proposed elaborate theoretical
scenario for real-time dynamics of non-abelian gauge theories at high
temperature. We see no sign of the predicted behavior. This indicates that
perturbative concepts like color conductivity and Landau damping might be
irrelevant at temperatures corresponding to the electroweak scale.


title: Charmed baryons in bootstrap quark model

abstract:
  In the framework of dispersion relation technique the relativistic
three-quark equations including heavy quarks are found. The approximate
solutions of the relativistic three-particles equations based on the extraction
of leading singularities of amplitudes are obtained. The mass values of S-wave
multiplets of charmed baryons are calculated.


title: Spin effects in tau-lepton pair production at LHC

abstract:
  Question of the proper incorporation of spin effects in tau lepton decays is
often of importance. In present work, case of the Z/gamma to tau+ tau-
production mechanism is studied in detail. As an example, the effects due to
the spin correlations on the potential for the Minimal Supersymmetric Standard
Model (MSSM) Higgs searches in the tau tau decay channel at the Large Hadron
Collider (LHC) are discussed. For these processes, the Standard Model Z/gamma
to tau tau -pair production is a dominant background.
  The spin effects in high energy physics reactions, can be implemented up to
certain approximation, independently of the algorithm and matrix elements used
by the production program. Information stored on every generated event can be
sufficient. The algorithm based on such approximation is documented. Question
of the theoretical uncertaintity is discussed only partly.


title: Remarks on photon-hadron interactions

abstract:
  Theoretical aspects of VMD and related approaches to real photon-hadron
interaction are discussed. The work relies on special relativity, properties of
linearly polarized photons, angular momentum conservation and relevant
experiments. It is explained why VMD and similar approaches should not be
regarded as part of a theory but, at most, as phenomenological models. A
further experiment pertaining to this issue is suggested.


title:
Photon-Neutrino Interactions in Magnetic Field through Neutrino Magnetic
  Moment

abstract:
  We study the neutrino-photon processes like $\gamma\gamma\to\nu\bar{\nu}$ in
the presence of uniform external magnetic field for the case when neutrinos can
couple to the electromagnetic field directly through their dipole magnetic
moment and obtain the stellar energy loss. The process would be of special
relevance in astrophysical situations where standard left-handed neutrinos are
trapped and the right handed neutrinos produced through the spin flip
interaction induced by neutrino magnetic moment alone can freely stream out.


title:
Higgs Radiation off Quarks in the Standard Model and supersymmetric
  Theories at e+e- Colliders

abstract:
  Yukawa couplings between Higgs bosons and quarks in the Standard Model (SM)
and supersymmetric theories can be measured in the processes e+e- -> Q\bar{Q} +
Higgs. The cross sections and Higgs energy distributions of these processes in
the SM and minimal supersymmetric model have been determined including the
complete set of next-to-leading order QCD corrections for all channels.


title: Dynamical CP Violation and Flavour-Changing Processes

abstract:
  We investigate the phenomenological constraints on a model where, besides the
standard model Higgs sector, there is an effective new strong interaction
acting on the third generation of quarks and characterized by a $\theta$-like
term. This $\theta$ term induces electroweak symmetry breaking and leads to
dynamical spontaneous CP violation. We show that the constraints coming from K
physics and the electric dipole moment of the neutron impose that the new
physics scale should be of the order of 35 TeV. Contrary to naive expectations,
the predictions of the model for B physics are very close to the standard model
ones. The main differences appear in processes involving the up quarks such as
$D^0-\bar{D}^0$ mixing and in the electric dipole moment of the neutron, which
should be close to the experimental limit. Possible deviations from the
standard model predictions for CP asymmetries in B decays are also considered.


title: QCD Signatures of Narrow Graviton Resonances in Hadron Colliders

abstract:
  We show that the characteristic p_\perp spectrum yields valuable information
for the test of models for the production of narrow graviton resonances in the
TeV range at LHC. Furthermore, it is demonstrated that in those scenarios the
parton showering formalism agrees with the prediction of NLO matrix element
calculations.


title: Magnetic charge of finite lifetime in SU(2) gluodynamics

abstract:
  A self-dual, localized solution to the classical SU(2) Yang-Mills equation in
Euclidean spacetime, which formally possesses infinite action, is investigated
in view of its U(1) charge content after Abelian projection. This is suggested
by noting that the solution satisfies 't Hooft's differential projection
condition away from the singularities. As a result the existence of dynamical,
magnetic charge of finite lifetime is established. A covariant cutoff for the
action is introduced by demanding the solution to be close to an instanton
topologically. This is in analogy to the \underline{calculation} of the mass of
a point charge in classical electrodynamics or the subtraction of diverging
self-energies of magnetic monopoles as discussed in the literature. The Wilson
loop is evaluated in the background of a dilute gas. Assuming identical
integrals over size distributions, the corresponding static quark/anti-quark
potential at infinite spatial separation can be seizably higher than the
potential in a dilute instanton gas.


title: Mesons on a transverse lattice

abstract:
  The meson eigenstates of the light-cone Hamiltonian in a coarse transverse
lattice gauge theory are investigated. Building upon previous work in pure
gauge theory, the Hamiltonian and its Fock space are expanded in powers of
dynamical fields. In the leading approximation, the couplings appearing in the
Hamiltonian are renormalised by demanding restoration of space-time symmetries
broken by the cut-off. Additional requirements from chiral symmetry are
discussed and difficulties in imposing them from first principles in the
leading approximation are noted. A phenomenological calculation is then
performed, in which chiral symmetry in spontaneously broken form is modelled by
imposing the physical pion-rho mass splitting as a constraint. The light-cone
wavefunctions of the resulting Hamiltonian are used to compute decay constants,
form factors and quark momentum and spin distributions for the pion and rho
mesons. Extensions beyond leading order, and the implications for first
principles calculations, are briefly discussed.


title: Mass and Transverse Mass Effects on the Hadron Emitter Size

abstract:
  We investigate the dependence of the longitudinal emitter dimension of
identical bosons, produced in the hadronic Z$^0$ decays, on their transverse
mass obtained from 2-dimensional Bose-Einstein correlations (BEC) analyses. We
show that this dependence is well described by the expression
$r_{||}=c\sqrt{\hbar\Delta t}/\sqrt{m_T}$, deduced from the uncertainty
relations, setting $\Delta t$ to be a constant of the order of $10^{-24}$ sec.
This equation is essentially identical to the one previously applied to the
1-dimensional BEC results for the emitter radius dependence on the boson mass
itself. It is further shown that a very similar behaviour exists also for the
dependence of the interatomic separation in Bose condensates on their atomic
masses when they are at the same very low temperature.


title: $\gamma \gamma$ cross-sections and $\gamma \gamma$ colliders

abstract:
  We summarize the predictions of different models for total $\gamma \gamma$
cross-sections. The experimentaly observed rise of $\sigma_{\gamma \gamma}$
with $\sqrt{s_{\gamma \gamma}}$, faster than that for $\sigma_{\bar p p}$,
$\sigma_{\gamma p}$ is in agreement with the predictions of the Eikonalized
Minijet Models as opposed to those of the Regge-Pomeron models. We then show
that a measurement of $\sigma_{\gamma \gamma}$ with an accuracy of $\lessapprox
8-9% (6-7%)$ is necessary to distinguish among different Regge-Pomeron type
models (among the different parametrisations of the EMM models) and a precision
of $\lessapprox$ 20% is required to distinguish among the predictions of the
EMMs and of those models which treat like 'photon like a proton', for the
energy range $300 < \sqrt{s_{\gamma \gamma}} < 500$ GeV. We further show that
the difference in model predictions for $\sigma_{\gamma \gamma}$ of about a
factor 2 at $\sqrt{s_{\gamma \gamma}} = 700 $ GeV reduces to $\sim$ 30% when
folded with bremsstrahlung $\gamma$ spectra to calculate $\sigma ({e^+e^- \to
e^+e^-\gamma \gamma \to e^+e^-X})$. We point out then the special role that
$\gamma \gamma$ colliders can play in shedding light on this


title: Total Photonic and Hadronic Cross-sections

abstract:
  We discuss total cross-sections within the context of the QCD calculable
mini-jet model, highlighting its successes and failures. In particular we show
its description of $\gamma \gamma \to hadrons$ and compare it with OPAL and L3
data. We extrapolate this result to $\gamma p$ total cross-sections and propose
a phenomenological ans\"atz for virtual photon cross-sections. We point out
that the good agreement with data obtained with the Eikonal Minijet Model
should not hide the many uncertainties buried in the impact parameter
distribution. A model obtained from Soft Gluon Summation is briefly discussed
and its application to hadronic cross-sections is shown.


title: Complete angular analysis of polarized top decay at O(alpha_s)

abstract:
  We calculate the O(alpha_s) radiative corrections to the three spin
independent and five spin dependent structure functions that describe the
angular decay distribution in the decay of a polarized top quark into a W-boson
(followed by the decay W^{+} -> l^{+} + nu_l or by W^{+} -> anti-q + q and a
bottom quark. The angular decay distribution is described in cascade fashion,
i.e. the decay t(uparrow) -> W^{+} + X_b is analyzed in the top rest system
while the subsequent decay W^{+} -> l^{+} + nu_l (or W^{+} -> anti-q + q) is
analyzed in the W rest frame. We present our results for the eight O(alpha_s)
integrated structure functions in analytical form keeping the mass of the
bottom quark finite. In the limit m_b -> 0 the structure function expressions
reduce to rather compact forms.


title: On the 1/Q correction to the C-parameter at two loops

abstract:
  We provide an analytical calculation at the two loop level of the real
non-abelian contribution to the leading (1/Q) correction to the mean value of
the C parameter in e+e- annihilation, to complement the existing calculation of
the abelian contribution; and we compare the result with the numerical `Milan
factor' obtained using the soft approximation. We find agreement with the
previous results. The use of the pinch technique to separate the various
contributions yields insights into the structure of renormalon-type diagrams in
a non-abelian theory.


title:
Dynamical SU(3) linear sigma model and the mixing of eta'-eta and
  sigma-f_0 mesons

abstract:
  The SU(3) linear sigma model is dynamically generated in loop-order using the
nonstrange-strange basis. Only self-consistent logarithmic divergent graphs are
needed, with quadratic divergent graphs replaced by SU(3) mass-shell equal
splitting laws. The latter lead to an eta'-eta mixing angle of 41.84 deg which
is consistent with phenomenology. Finally this above SU(3) linear sigma model
in turn predicts strong decay rates which are all compatible with data.


title:
Measurement of Lambda polarization in muon neutrino charged current
  interactions in NOMAD

abstract:
  The Lambda polarization in muon neutrino charged current interactions has
been measured in the NOMAD experiment. We observe negative polarization along
the W - boson direction which is enhanced in the target fragmentation region:
  Px (xF < 0) = -0.21 +/- 0.04(stat) +/- 0.02(sys). In the current
fragmentation region we find: Px (xF > 0) = -0.09 +/- 0.06(stat) +/- 0.03(sys).
These results provide a test of different models describing the nucleon spin
composition and the spin transfer mechanisms. A significant transverse
polarization (in the direction orthogonal to the Lambda production plane) has
been observed for the first time in a neutrino experiment: Py = -0.22 +/-
0.03(stat) +/- 0.01(sys). The dependence of the absolute value of Py on the
Lambda transverse momentum with respect to the hadronic jet direction is in
qualitative agreement with the results from unpolarized hadron-hadron
experiments.


title:
Effective Field Theory for the Crystalline Colour Superconductive Phase
  of QCD

abstract:
  We present an effective field theory for high density, low temperature QCD in
the crystalline colour superconductive phase (LOFF phase). This interesting
phase of QCD is characterized by a gap parameter with a crystalline pattern,
breaking traslational and rotational invariance, and could have astrophysical
applications. In the effective theory the fermions have a Majorana mass, which,
besides colour, breaks translation and rotation symmetries. Fermions couple to
the three phonons arising from the breaking of rotation and translation
invariance. Integrating out the fermions leads eventually to an effective
lagrangian in terms of the phonon fields only, which satisfies an anisotropic
dispersion relation.


title:
Relativistic instant-form approach to the structure of two-body
  composite systems

abstract:
  A new approach to the electroweak properties of two-particle composite
systems is developed. The approach is based on the use of the instant form of
relativistic Hamiltonian dynamics. The main novel feature of this approach is
the new method of construction of the matrix element of the electroweak current
operator. The electroweak current matrix element satisfies the relativistic
covariance conditions and in the case of the electromagnetic current also the
conservation law automatically. The properties of the system as well as the
approximations are formulated in terms of form factors. The approach makes it
possible to formulate relativistic impulse approximation in such a way that the
Lorentz-covariance of the current is ensured. In the electromagnetic case the
current conservation law is ensured, too. The results of the calculations are
unambiguous: they do not depend on the choice of the coordinate frame and on
the choice of "good" components of the current as it takes place in the
standard form of light--front dynamics. Our approach gives good results for the
pion electromagnetic form factor in the whole range of momentum transfers
available for experiments at present time, as well as for lepton decay constant
of pion.


title:
Determining $|V_{ub}|$ from the $\bar B\to X_u\ell\bar\nu$ dilepton
  invariant mass spectrum

abstract:
  The invariant mass spectrum of the lepton pair in inclusive semileptonic
$\bar B\to X_u \ell\bar\nu$ decay yields a model independent determination of
$|V_{ub}|$. Unlike the lepton energy and hadronic invariant mass spectra,
nonperturbative effects are only important in the resonance region, and play a
parametrically suppressed role when $d\Gamma / dq^2$ is integrated over $q^2 >
(m_B-m_D)^2$, which is required to eliminate the $\bar B\to X_c \ell\bar\nu$
background. We discuss these backgrounds for $q^2$ slightly below
$(m_B-m_D)^2$, and point out that instead of $q^2 > (m_B-m_D)^2 = 11.6 GeV^2$,
the cut can be lowered to $q^2 \gtrsim 10.5 GeV^2$. This is important
experimentally, particularly when effects of a finite neutrino reconstruction
resolution are included.


title: Anomaly, Charge Quantization and Family

abstract:
  We first review the three known chiral anomalies in four dimensions and then
use the anomaly free conditions to study the uniqueness of quark and lepton
representations and charge quantizations in the standard model. We also extend
our results to theory with an arbitrary number of color. Finally, we discuss
the family problem.


title: Determination of V_ub from semileptonic B decays

abstract:
  The hadronic mass distribution in semileptonic B-meson decays can be used for
extracting the charmless part and thus determining the |V_ub/V_cb| ratio. We
take into account first-order perturbative as well as non-perturbative QCD
corrections. The sensitivity to model assumptions is studied and an estimate of
the remaining uncertainties is performed.


title: Standard-Model-like scenarios in the 2HDM and Photon Collider potential

abstract:
  After operations at the LHC and e^+e^- Linear Colliders it may be found that
a Standard-Model-like scenario is realized. In this scenario no new particle
will be discovered, except a single Higgs boson having partial widths or
coupling constants with fundamental particles, whose squares are close, within
anticipated experimental uncertainty, to those of the SM. Experiments at a
Photon Collider can resolve whether the SM or e.g. the Two-Higgs-Doublet Model
is realized in Nature.
  For the SM-like realizations of the 2HDM (II) we study the loop couplings of
the Higgs boson with \gamma\gamma and Z \gamma, and also with gluons. The
deviation of the two-photon width from its SM value is generally higher than
the expected inaccuracy in the measurement of \Gamma_{\gamma \gamma} at a
Photon Collider. The deviation is sensitive to the parameters of the Higgs self
interaction.


title: Gluon-Photon mixing in dense QCD

abstract:
  At high baryonic density with the formation of a diquark condensate $\Delta
\neq 0$, the QCD color symmetry is spontaneously broken.
  Being massive by the Anderson-Higgs mechanism, gluon and photon should mix
together within two linear combinations due to the color non-conservation.
Consequently a gluon $\widetilde{G}$ could decay into an $e^- e^+$ pair via its
photon component. With a low invariant mass (about a few ten MeV) and an
extremely narrow width peaking above the continuum background, the purely
leptonic decay of a strongly-interacting gluon $\widetilde{G} \to e^- + e^+$
constitutes a very distinctive signature of the color superconductivity phase.
By a similar scenario of gluon-$Z$ mixing, another "missing-energy" decay into
invisible neutrinos $\widetilde{G} \to \nu +\bar{\nu}$ could arise, its
amplitude is however $(\Delta/M_Z)^2$ power-suppressed.


title: J/\psi production through resolved photon processes at e+ e- colliders

abstract:
  We consider J/psi photoproduction in e+ e- as well as linear photon
colliders. We find that the process is dominated by the resolved photon
channel. Both the once-resolved and twice-resolved cross-sections are sensitive
to (different combinations of) the colour octet matrix elements. Hence, this
may be a good testing ground for colour octet contributions in NRQCD. On the
other hand, the once-resolved J/psi production cross-section, particularly in a
linear photon collider, is sensitive to the gluon content of the photon. Hence
these cross-sections can be used to determine the parton distribution
functions, especially the gluon distribution, in a photon, if the colour octet
matrix elements are known.


title: Possible Flavor Mixing Structures of Lepton Mass Matrices

abstract:
  To search for possible textures of lepton mass matrices, we systematically
examine flavor mixing structures which can lead to large lepton mixing angles.
We find out 37 mixing patterns are consistent with experimental data, taking
into account phase factors in the mixing matrices. Only six of the patterns can
explain the observed data without any tuning of parameters, while the others
need particular choices for the phase values. It is found that these six mixing
patterns are those predicted by the models which have been proposed to account
for fermion mass hierarchies. On the other hand, the others may give new flavor
mixing structures of lepton mass matrices and therefore new possibilities of
model construction.


title: Generalized parton distributions with helicity flip

abstract:
  We show that for both quarks and gluons there are eight generalized parton
distributions in the proton: four which conserve parton helicity and four which
do not. We explain why time reversal invariance does not reduce this number
from eight to six, as previously assumed in the literature.


title: Flavour Dynamics: CP Violation and Rare Decays

abstract:
  These lectures give an up to date description of CP violation and rare decays
of K and B mesons and consist of ten chapters: i) Grand view of the field
including CKM matrix and the unitarity triangle, ii) General aspects of the
theoretical framework based on effective weak Hamiltonians, the operator
product expansion and the renormalization group, iii) Particle-antiparticle
mixing and various types of CP violation, iv) Standard analysis of the
unitarity triangle, v) The ratio epsilon'/epsilon, vi) Rare decays K^+ -> pi^+
nu barnu and K_L to pi^0 nu barnu, vii) Express review of other rare decays,
viii) CP violation in B decays, ix) A brief look beyond the Standard Model
discussing in particular the models with minimal flavour violation, x)
Perspectives for the coming years.


title: Instantons and the $\Delta I=1/2 $ Rule

abstract:
  The instanton induced interaction leads to a significant enhancement of the
$A_0$ weak amplitude determining the $\Delta I=1/2$ rule, through the
contribution of operators with dimension d=9, as we show in the weak $K\to
\pi\pi$ decay.


title: QCD on a transverse lattice

abstract:
  We present results from a transverse lattice study of low lying mesons.
Special emphasis is put on the issue of Lorentz invariant energy-momentum
dispersion relations for these mesons. The light-cone wave function for the
$\pi$ obtained in this framework is very close to its asymptotic shape.


title: Light Gauginos - a Solution to More than the EDMs?

abstract:
  In this talk I want to present questions that remained unclear to me in the
last years. These questions concern the Electric Dipole Moments of electron and
neutron and the way people exclude regions of parameter space.


title:
Effects of Gauge Interactions on Fermion Masses in Models with Fermion
  Wavefunctions Separated in Higher Dimensions

abstract:
  We consider models that generate hierarchies via the separation of fermion
wavefunctions in higher-dimensional spaces. We calculate the effects of gauge
interactions between fermions and show that these are important and could help
to explain (i) why the heaviest known fermion is a charge 2/3 quark, rather
than a charge -1/3 quark or a lepton, (ii) why this fermion has a mass $m_t$
comparable to the electroweak symmetry breaking scale $M_{ew}$, (iii) the
patterns $m_t >> m_b > m_\tau$ and $m_c >> m_s > m_\mu$, and (iv) the smallness
of neutrino masses.


title:
Flavor symmetry breaking, baryons magnetic moments, and low energy
  phenomenology of hadrons

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 mixings that break
flavor and parity symmetries, is studied. Applications to non-leptonic and weak
radiative decays of hyperons are discussed. The results are very encouraging
but should be improved by eventually including the W and Z contributions,
assumed small (non-enhanced) in this work.


title:
How Can a Heavy Higgs Boson be Consistent with the Precision Electroweak
  Measurements?

abstract:
  The fit of precision electroweak data to the Minimal Standard Model currently
gives an upper limit on the Higgs boson mass of 170 GeV at 95% confidence.
Nevertheless, it is often said that the Higgs boson could be much heavier in
more general models. In this paper, we critically review models that have been
proposed in the literature that allow a heavy Higgs boson consistent with the
precision electroweak constraints. All have unusual features, and all can be
distinguished from the Minimal Standard Model either by improved precision
measurements or by other signatures accessible to next-generation colliders.


title:
Cosmic string induced sheet like baryon inhomogeneities at quark-hadron
  transition

abstract:
  Cosmic strings moving through matter produce wakes where density is higher
than the background density. We investigate the effects of such wakes occurring
at the time of a first order quark-hadron transition in the early universe and
show that they can lead to separation of quark-gluon plasma phase in the wake
region, while the region outside the wake converts to the hadronic phase.
Moving interfaces then trap large baryon densities in sheet like regions which
can extend across the entire horizon. Typical separation between such sheets,
at formation, is of the order of a km. Regions of baryon inhomogeneity of this
nature, i.e. having a planar geometry, and separated by such large distance
scales, appear to be well suited for the recent models of inhomogeneous
nucleosynthesis to reconcile with the large baryon to photon ratio implied by
the recent measurements of the cosmic microwave background power spectrum.


title: High density QCD at THERA

abstract:
  These notes are a summary of our predictions for the new THERA project,
related to deep inelastic scattering in the region of ultra low $x$ ($x \to
10^{-7}$). We collect here predictions that satisfy two criteria (i) they do
not depend on specific features of the model that we have to use to estimate a
possible effect; and (ii) they do not contradict the HERA data.


title:
On the Ambiguity of the Solution of the Muskhelishvili-Omnes Integral
  Equation

abstract:
  The solution of the Muskhelishvili-Omnes Integral Equation is ambiguous by a
real polynomial. The coefficients of this polynomial can be fixed either by the
knowledge of the low energy parameters or by the asymptotic behavior of the
form factor. The role of the contact terms of the low energy effective
Lagrangian is explicitly analysed.


title: Zero-dimensional field theory

abstract:
  A study of zero-dimensional theories, based on exact results, is presented.
First, relying on a simple diagrammatic representation of the theory, equations
involving the generating function of all connected Green's functions are
constructed. Second, exact solutions of these equations are obtained for
several theories. Finally, renormalization is carried out. Based on the
anticipated knowledge of the exact solutionsthe full dependence on the
renormalized coupling constant is studied.


title: $\mu \to e \gamma$ from Supersymmetry without R parity

abstract:
  Starting from the new sources of $LL$- and $LR$- scalar (slepton) mixings due
to R-parity violation, we discuss the structure of lepton-flavor violation
focusing on the radiative decay of muon into electron. Using an optimal
parametrization, we give the general formulae for the one-loop contributions.
from which we discuss all combinations of R-parity violating parameters having
possibly a substantial contribution to the $\mu \to e \gamma$ decay width. An
exact numerical study is performed to obtain explicit bounds on the parameters
under the present experimental limit. The most interesting one involves a
combination of bilinear and trilinear couplings.


title: Unintegrated parton distributions

abstract:
  We describe how to calculate the parton distributions $f_a(x, k_t^2, \mu^2)$,
unintegrated over the parton transverse momentum $k_t$, from auxiliary
functions $h_a(x, k_t^2)$, which satisfy single-scale evolution equations. The
formalism embodies both DGLAP and BFKL contributions, and accounts for the
angular ordering which comes from coherence effects in gluon emission. We check
that the unintegrated distributions give the measured values of the deep
inelastic structure function $F_2(x, Q^2)$.


title:
E_6 unification model building III. Clebsch-Gordan coefficients in E_6
  tensor products of the 27 with higher dimensional representations

abstract:
  $E_6$ is an attractive group for unification model building. However, the
complexity of a rank 6 group makes it non-trivial to write down the structure
of higher dimensional operators in an $E_6$ theory in terms of the states
labeled by quantum numbers of the Standard Model gauge group. In this paper, we
show the results of our computation of the Clebsch-Gordan coefficients for the
products of the {\bf 27} with irreducible representations of higher
dimensionality: ${\bf 78}$, ${\bf 351}$, ${\bf 351^\prime}$, ${\bf \ol{351}}$,
and ${\bf \ol{351^\prime}}$. Application of these results to $E_6$ model
building involving higher dimensional operators is straightforward.


title: Bi-maximal Neutrino Mixing And Anomalous Flavor ${\cal U}(1)$

abstract:
  We describe how bi-maximal neutrino mixing can be realized in realistic
models based on MSSM and SUSY GUTs such as SU(5) and SO(10). A crucial role is
played by an anomalous ${\cal U}(1)$ flavor symmetry, which also helps
understand the observed charged fermion mass hierarchies and the magnitudes of
the CKM matrix elements. While in MSSM a variety of solutions for the solar
neutrino puzzle are possible, SUSY SU(5) and SO(10) only permit the large
mixing angle MSW solution. Models in which the ${\cal U}(1)$ symmetry also
mediates SUSY breaking allow both the large mixing angle and the low MSW
solutions.
  We also present renormalization group studies for the neutrino mass matrix,
generated through the ${\cal U}(1)$ flavor symmetry. Our analysis shows that
renormalization does not change the desirable picture of bi-maximal mixing.


title: Optimal Charge and Color Breaking conditions in the MSSM

abstract:
  In the MSSM, we make a careful tree-level study of Charge and Color Breaking
conditions in the plane $(H_2, \tilde{u}_L, \tilde{u}_R)$, focusing on the top
quark scalar case. A simple and fast procedure to compute the VEVs of the
dangerous vacuum is presented and used to derive a model-independent optimal
CCB bound on $A_t$. This bound takes into account all possible deviations of
the CCB vacuum from the D-flat directions. For large $\tan \beta$, it provides
a CCB maximal mixing for the stop scalar fields $\tilde{t}_1,\tilde{t}_2$,
which automatically rules out the Higgs maximal mixing $|A_t|=\sqrt{6}
m_{\tilde{t}}$. As a result, strong limits on the stop mass spectrum and a
reduction, in some cases substantial, of the one-loop upper bound on the
CP-even lightest Higgs boson mass, $m_h$, are obtained. To incorporate one-loop
leading corrections, this tree-level CCB condition should be evaluated at an
appropriate renormalization scale which proves to be the SUSY scale.


title: Distributions of N=1 QCD

abstract:
  We describe the N=1 supersymmetric evolution of the parton distributions with
coupled gluinos and scalar quarks (Exact Supersymmetric Altarelli Parisi or
ESAP). Superymmetric distributions are generated radiatively and studied as a
function of both a matching scale (the match is to an intermediate AP
evolution), parameterized by a scalar quark mass, and a final evolution scale.
The analysis involves also a comparison with the regular AP evolution.
Predictions for all the distributions are presented.


title:
Probing the SUSY Higgs boson couplings to scalar leptons at high-energy
  $e^+e^-$ colliders

abstract:
  We discuss the production at $e^+e^-$ colliders of Higgs bosons in
association with both the scalar leptons and the lightest neutralinos in the
Minimal Supersymmetric extension of the Standard Model. While the rates for
associated Higgs production with neutralinos and first/second generation
sleptons are rather tiny, the cross section for the production of the lightest
Higgs boson $h$ with scalar $\tau$ lepton pairs can reach the femtobarn level
at c.m. energies at and above 500 GeV in favorable regions of the parameter
space, making this process potentially detectable at a high-luminosity $\ee$
collider, in particular in the $\gamma \gamma$ option. This would provide a
determination of the $h \tilde{\tau} \tilde{\tau}$ coupling and opens up the
possibility of measuring the parameter $\tan \beta$.


title: Single production of charged Higgs bosons at linear colliders

abstract:
  We discuss single charged Higgs boson production from $e^+e^-$ annihilation
at next generation linear colliders. They can be important to study the
phenomenology of charged Higgs bosons, especially when charged Higgs bosons are
too heavy to be produced by the pair production mechanism. Cross sections for
various single production processes are evaluated at the leading order. Our
analysis shows that in some parameter regions the phenomenology of charged
Higgs bosons can be explored even beyond the kinematic limit for pair
production by using single production processes.


title: Canceling Quadratic Divergences in a Class of Two-Higgs-Doublet Models

abstract:
  The Newton-Wu conditions for the cancellation of quadratic divergences in a
class of two-Higgs-doublet models are analyzed as to how they may be satisfied
with a typical extension of the Standard Model of particle interactions.


title: Bell inequalities for entangled kaons and their unitary time evolution

abstract:
  We investigate Bell inequalities for neutral kaon systems from Phi resonance
decay to test local realism versus quantum mechanics. We emphasize the unitary
time evolution of the states, that means we also include all decay product
states, in contrast to other authors. Only this guarantees the use of the
complete Hilbert space. We develop a general formalism for Bell inequalities
including both arbitrary "quasi spin" states and different times; finally we
analyze Wigner-type inequalities. They contain an additional term, a correction
function h, as compared to the spin 1/2 or photon case, which changes
considerably the possibility of quantum mechanics to violate the Bell
inequality. Examples for special "quasi spin" states are given, especially
those which are sensitive to the CP parameters epsilon and epsilon'.


title: Remarks on flavor-neutrino propagators and oscillation formulae

abstract:
  We examine the general structure of the formulae of neutrino oscillations
proposed by Blasone and Vitiello(BV). Reconstructing their formulae with the
retarded propagators of the flavor neutrino fields for the case of many
flavors, we can get easily the formulae which satisfy the suitable boundary
conditions and are independent of arbitrary mass parameters $\{\mu_{\rho}\}$,
as is obtained by BV for the case of two flavors. In this two flavor case, our
formulae reduce to those obtained by BV under $T$-invariance condition.
Furthermore, the reconstructed probabilities are shown to coincide with those
derived with recourse to the mass Hilbert space ${\cal H}_{m}$ which is
unitarily inequivalent to the flavor Hilbert space ${\cal H}_{f}$. Such a
situation is not found in the corresponding construction a la BV. Then the new
factors in the BV's formulae, which modify the usual oscill ation formulae, are
not the trace of the flavor Hilbert space construction, but come from
Bogolyubov transformation among the operators of spin-1/2 ne utrino with
different masses.


title: Supersymmetry and Superpartners

abstract:
  A brief summary is given of studies on supersymmetry and the spectrum of
superparticles presented at the Linear Collider Workshop 2000.


title:
Quark Transversity Distribution in Perturbative QCD: Light-Front
  Hamiltonian Approach

abstract:
  To resolve the current ambiguity in the splitting function corresponding to
the quark transversity distribution $h_1(x)$, we calculate $h_1(x)$ for a
dressed quark in light-front Hamiltonian perturbation theory. Our result agrees
with the expected form of the splitting function found in the literature and
disagrees with the recent calculation in \cite{kuhn}. We emphasize the
importance of quark mass in $h_1(x)$ in perturbative QCD and show its
connection with a part of $g_T$.


title:
Direct Determination of the CKM Matrix from Decays of W Bosons and Top
  Quarks at High Energy e+e- Colliders

abstract:
  At proposed high energy linear e+e- colliders a large number of W bosons and
top quarks will be produced. We evaluate the potential precision to which the
decay branching ratios into the various quark species can be measured, implying
also the determination of the respective CKM matrix elements. Crucial is the
identification of the individual quark flavours, which can be achieved
independent of QCD models. For transitions involving up quarks the accuracy is
of the same order of magnitude as has been reached in hadron decays. We
estimate that for charm transitions a precision can be reached that is superior
to current and projected traditional kinds of measurements. The t->b
determination will be significantly improved, and for the first time a direct
measurement of the t->s transition can be made. In all cases such a
determination is complementary to the traditional way of extracting the CKM
matrix elements.


title: The Algebraic Method

abstract:
  Combining the effect of an intermediate renormalization prescription (zero
momentum subtraction) and the background field method (BFM), we show that the
algebraic renormalization procedure needed for the computation of radiative
corrections within non-invariant regularization schemes is drastically
simplified. The present technique is suitable for gauge models and, here, is
applied to the Standard Model. The use of the BFM allows a powerful
organization of the counterterms and avoids complicated Slavnov-Taylor
identities. Furthermore, the Becchi-Rouet-Stora-Tyutin (BRST) variation of
background fields plays a special role in disentangling Ward-Takahashi
identities (WTI) and Slavnov-Taylor identities (STI). Finally, the strategy to
be applied to physical processes is exemplified for the process $b\to s\gamma$.


title: Low-energy constraints from unification of matter multiplets

abstract:
  We study the low-energy consequences of the mass and mixing angle relations
in grand unified theories (GUT), which follow from an assumption that some
quarks and leptons are placed in the same GUT multiplets. This assumption is a
simple extension of that for the well-known bottom/tau mass ratio, which is one
of the most successful predictions of grand unification of matter multiplets.
We show that imposing the GUT relations leads naturally to a limited parameter
space from the large lepton mixing between the second and third generations.


title:
A priori mixed hadrons, hyperon non-leptonic decays, and the |\Delta
  I|=1/2 rule

abstract:
  The |\Delta I|=1/2 rule in non-leptonic decays of hyperons can be naturally
understood by postulating a priori mixed physical hadrons, along with the
isospin invariance of the responsible transition operator. It is shown that
this operator can be identified with the strong interaction Yukawa hamiltonian.


title: Making Neutrinos Massive with an Axion in Supersymmetry

abstract:
  The minimal supersymmetric standard model (MSSM) of particle interactions is
extended to include three singlet (right-handed) neutrino superfields together
with three other singlet superfields. The resulting theory is assumed to be
invariant under an anomalous global U(1) (Peccei-Quinn) symmetry with one
fundamental mass $m_2$. The soft breaking of supersymmetry at the TeV scale is
shown to generate an axion scale $f_a$ of order $m_2$. Neutrino masses are
generated by $f_a$ according to the usual seesaw mechanism.


title: The Renormalization Group Equation for the Color Glass Condensate

abstract:
  We present an explicit and simple form of the renormalization group equation
which governs the quantum evolution of the effective theory for the Color Glass
Condensate (CGC). This is a functional Fokker-Planck equation for the
probability density of the color field which describes the CGC in the covariant
gauge. It is equivalent to the Euclidean time evolution equation for a second
quantized current-current Hamiltonian in two spatial dimensions. The quantum
corrections are included in the leading log approximation, but the equation is
fully non-linear with respect to the generally strong background field. In the
weak field limit, it reduces to the BFKL equation, while in the general
non-linear case it generates the evolution equations for Wilson-line operators
previously derived by Balitsky and Kovchegov within perturbative QCD.


title: Number of Fermion Generations Derived from Anomaly Cancellation

abstract:
  We prove that global anomaly cancellation requires more than one generation
of quarks and leptons, provided that the standard model fields propagate in two
universal extra dimensions. Furthermore, if the fermions of different
generations have the same gauge charges and chiralities, then global anomaly
cancellation implies that there must be three generations.


title: Indirect Detection of Neutralino Dark Matter up to TeV Scale

abstract:
  In this paper, we will describe the results of SUSY parameter space searches
including minimal supergravity, non-universal supergravity and minimal
supersymmetry and the implications on the indirect detection of neutralino dark
matter. We give special attention to the effects of detector thresholds, solar
absorption of neutrinos and hadronization of neutralino annihilation products.
These effects are known to be important in calculating accurate event rates.


title: Factorization and hadronic B decays in the heavy quark limit

abstract:
  Recent theoretical investigations of two-body hadronic B decays have provided
justification for the use of the factorization ansatz to evaluate the B decay
matrix elements. Motivated by this, we present simplified formulae for a wide
range of B decays into the lowest mass pseudoscalar and vector mesons. These
formulae, valid in the heavy quark limit, involve a reduced set of soft QCD
parameters and, although resulting in some loss of accuracy, should still
provide an adequate and transparent tool with which to confront data for some
time to come. Finally, we confront these formulae with data on 19 channels.


title: Threshold resummation for exclusive B meson decays

abstract:
  We argue that double logarithmic corrections $\alpha_s\ln^2 x$ need to be
resumed in perturbative QCD factorization theorem for exclusive $B$ meson
decays, when the end-point region with a momentum fraction $x\to 0$ is
important. These double logarithms, being of the collinear origin, are absorbed
into a quark jet function, which is defined by a matrix element of a quark
field attached by a Wilson line. The factorization of the jet function from the
decay $B\to\gamma l\bar\nu$ is proved to all orders. Threshold resummation for
the jet function leads to a universal, {\it i.e.}, process-independent, Sudakov
factor, whose qualitative behavior is analyzed and found to smear the end-point
singularities in heavy-to-light transition form factors.


title: Spin-Dependent Structure Functions of the Photon

abstract:
  The implications of the positivity constraint on the presently unknown
polarized structure function of the photon, $g_1^{\gamma}(x,Q^2)$, are studied
in detail. In particular the non-trivial consequences of this constraint,
$|g_1^{\gamma}(x,Q^2)|\leq F_1^{\gamma}(x,Q^2)$, in the next-to-leading order
analysis of $g_1^{\gamma}$ are pointed out by employing appropriate (DIS)
factorization schemes related to $g_1^{\gamma}$ and $F_1^{\gamma}$ (rather than
to $F_2^{\gamma}$).


title: Future Measurements of Transversity

abstract: A review of envisaged future quark transversity measurements is presented.


title:
Prediction of LSND effect as a "sterile" perturbation of the bimaximal
  texture for three active neutrinos

abstract:
  As a contribution to the hypothesis of mixing of three active neutrinos with,
at least, one sterile neutrino, we report on a simple $4\times4$ texture whose
$3\times3$ part arises from the popular bimaximal texture for three active
neutrinos $\nu_e,\nu_\mu,\nu_\tau$, where $c_{12}=1/\sqrt{2} = s_{12}$, $c_{23}
= 1/\sqrt{2} = s_{23}$ and $s_{13} = 0$. Such a $3\times 3$ bimaximal texture
is perturbed through a rotation in the 14 plane, where $\nu_4$ is the extra
neutrino mass state induced by the sterile neutrino $\nu_s$ which becomes
responsible for the LSND effect. Then, with $m^2_1 \simeq m^2_2$ we predict
that $\sin^2 2\theta_{\rm atm} = {1/2}(1+ c^2_{14}) \sim 0.95$ and $\sin^2
2\theta_{\rm LSND} = {1/2}s^4_{14} \sim 5\times10^{-3}$, and in addition
$\Delta m^2_{\rm atm} = \Delta m^2_{32}$ and $\Delta m^2_{\rm LSND} = |\Delta
m^2_{41}|$, where $c^2_{14} = \sin^2 2\theta_{\rm sol} \sim 0.9$ and $\Delta
m^2_{21} = \Delta m^2_{\rm sol} \sim 10^{-7} {\rm eV}^2$ if e.g. the LOW solar
solution is applied.


title: A Critical Reassessment of Q7 and Q8 Matrix Elements

abstract:
  We compare recent theoretical determinations of weak matrix elements of the
electroweak penguin operators Q7 and Q8. We pay special attention to the
renormalization scheme dependence of these determinations as well as to the
influence of higher dimension operators in the different approaches.


title: Introduction to low x physics and diffraction

abstract:
  The basic concepts relevant for the theoretical description of deep inelastic
scattering within the QCD improved parton model are introduced. Recent
developments in low $x$ DIS and in deep inelastic diffraction are briefly
summarised. This includes discussion of the BFKL dynamics including the
subleading effects and of the saturation model. The dedicated measurements,
which probe the QCD pomeron are also discussed.


title: Chiral fermions and gauge-fixing in five-dimensional theories

abstract:
  We study in detail the issue of gauge-fixing in theories with one universal
extra dimension, i.e. theories where both bosons and fermions display
Kaluza-Klein (KK) excitations. The extra dimension is compactified using the
standard orbifold construction for a massless chiral fermion. We carry out the
gauge-fixing procedure at the level of the five-dimensional theory and
determine the tree-level propagators and interaction vertices needed for
performing perturbative calculations with the effective four-dimensional theory
resulting after the compactification. The gauge-independence of the tree-level
S-matrix involving massive KK modes is verified using specific examples. In
order to obtain massive fermionic zero modes one has to enlarge the theory by
introducing a set of mirror fermions, a construction which is carried out in
detail. Finally, the gauge-independence of the tree-level S-matrix involving
the resulting new mass-eigenstates is proved by resorting to generalized
current conservation equations.


title: Explosive Collisions at RHIC?

abstract:
  Motivated by experimental results from RHIC, we suggest how a condensate for
the Polyakov loop might produce explosive behavior at the QCD phase transition.
This is due to a rapid rollover of the condensate field below the transition
temperature.


title:
Sum Rules of Neutrino Masses and CP Violation in the Four-Neutrino
  Mixing Scheme

abstract:
  We show that the commutator of lepton mass matrices is invariant under
terrestial matter effects in the four-neutrino mixing scheme. A set of
model-independent sum rules for neutrino masses, which may be generalized to
hold for an arbitrary number of neutrino families, are for the first time
uncovered. Useful sum rules for the rephasing-invariant measures of leptonic CP
violation have also been found. Finally we present a generic formula of
T-violating asymmetries and expect it to be applicable to the future
long-baseline neutrino oscillation experiments.


title: 't Hooft and Wilson loop ratios in the QCD plasma

abstract:
  The spatial 't Hooft loop measuring the electric flux and the spatial
Wilsonloop measuring the magnetic flux are analyzed in hot SU(N) gauge theory.
Both display area laws. On one hand the tension of the 't Hooft loop is
perturbatively calculable, in the same sense as the pressure. We show that the
O(g^3) contribution is absent. The ratio of multi-charged 't Hooft loops have a
remarkably simple dependence on the charge, true up to, but not including,
O(g^4). This dependence follows also from a simple model of free screened
colour charges. On the other hand the surface tension of the Wilsonloop is
non-perturbative. But in a model of screened free monopoles at very high
temperature the known area law follows. The density of these monopoles starts
to contribute to O(g^6) to the pressure. The ratio of the multicharged Wilson
loops is calculable and identical to that of the 't Hooft loops.


title: Measuring the Spin of the Higgs Boson

abstract:
  By studying the threshold dependence of the excitation curve and the angular
distribution in Higgs-strahlung at e+e- colliders, e+e- -> HZ, the spin of the
Higgs boson in the Standard Model and related extensions can be determined
unambiguously in a model-independent way.


title: Relativistic quark model and scalar diquarks charge radii

abstract:
  In the framework of relativistic quark model the behaviour of electromagnetic
form factors of diquarks with $ J^{P} = 0^{+} $ at small and intermediate
momentum transfer are determined. The charge radii of nonstrange and strange
scalar diquarks are calculated.


title:
Twist-4 Gluon Recombination Corrections for Deep Inelastic Structure
  Functions

abstract:
  We calculate twist--4 coefficient functions for the deep inelastic structure
function $F_2(x,Q^2)$ associated to 4--gluon operator matrix elements for
general values of the Bjorken variable $x$ and study the numerical effect on
the slope $\partial F_2(x,Q^2)/\partial \log Q^2$. It is shown that these
contributions diminish the strongly rising twist--2 terms towards small values
of $x$.


title:
An Analysis of the Next-to-Leading Order Corrections to the
  g_T(=g_1+g_2) Scaling Function

abstract:
  We present a general method for obtaining the quantum chromodynamical
radiative corrections to the higher-twist (power-suppressed) contributions to
inclusive deep-inelastic scattering in terms of light-cone correlation
functions of the fundamental fields of quantum chromodynamics. Using this
procedure, we calculate the previously unknown ${\cal O}(\alpha_s)$ corrections
to the twist-three part of the spin scaling function $g_T(x_B,Q^2)
(=g_1(x_B,Q^2)+g_2(x_B,Q^2))$ and the corresponding forward Compton amplitude
$S_T(\nu,Q^2)$. Expanding our result about the unphysical point $x_B=\infty$,
we arrive at an operator product expansion of the nonlocal product of two
electromagnetic current operators involving twist-two and -three operators
valid to ${\cal O}(\alpha_s)$ for forward matrix elements. We find that the
Wandzura-Wilczek relation between $g_1(x_B,Q^2)$ and the twist-two part of
$g_T(x_B,Q^2)$ is respected in both the singlet and non-singlet sectors at this
order, and argue its validity to all orders. The large-$N_c$ limit does not
appreciably simplify the twist-three Wilson coefficients.


title: Top-Bottom Color and Weak Doublets Seesaw

abstract:
  A brief overview of some of the last decade's developments in the
Top-mode/Topcolor class of models is presented. In addition, a new Topcolor
type scenario, named Top-Bottom Color, is suggested. A seesaw mechanism with
new weak doublet quarks has been introduced to lower the previous theoretical
prediction for the large top quark mass; without a seesaw mechanism and with a
low scale of Nambu - Jona-Lasinio triggering interactions, the top quark mass
was predicted to be \textit{O}(500GeV). In Top-Bottom Color an effective,
composite two Higgs doublet model is obtained where the third generation
isospin splitting is introduced via tilting interactions related to the broken
non-abelian gauge groups (i.e. without strong, triviality-sensitive U(1)
groups). To complete discussion a few notes on the fine tuning related to the
bottom quark mass are appended in an \textit{addendum}. A generic problem
(\textit{Why does the top Yukawa coupling equal one?}) of the Top-mode/Topcolor
class of models is pointed out as well. Furthermore, previous work on the third
generation seesaw mechanism with weak doublet quarks and dynamical top mass
production in the Topcolor spirit is discussed.


title: Extrapolation of K to \pi\pi decay amplitude

abstract:
  We examine the uncertainties involved in the off-mass-shell extrapolation of
the $K\rightarrow \pi\pi$ decay amplitude with emphasis on those aspects that
have so far been overlooked or ignored. Among them are initial-state
interactions, choice of the extrapolated kaon field, and the relation between
the asymptotic behavior and the zeros of the decay amplitude. In the inelastic
region the phase of the decay amplitude cannot be determined by strong
interaction alone and even its asymptotic value cannot be deduced from
experiment. More a fundamental issue is intrinsic nonuniqueness of off-shell
values of hadronic matrix elements in general. Though we are hampered with
complexity of intermediate-energy meson interactions, we attempt to obtain a
quantitative idea of the uncertainties due to the inelastic region and find
that they can be much larger than more optimistic views portray.


title: Supersymmetric radiative corrections at large tan beta

abstract:
  In the minimal supersymmetric extension of the Standard Model (MSSM), fermion
masses and Yukawa couplings receive radiative corrections at one loop from
diagrams involving the supersymmetric particles. The corrections to the
relation between down-type fermion masses and Yukawa couplings are enhanced by
tan beta, which makes them potentially very significant at large tan beta.
These corrections affect a wide range of processes in the MSSM, including
neutral and charged Higgs phenomenology, rare B meson decays, and
renormalization of the CKM matrix. We give a pedagogical review of the sources
and phenomenological effects of these corrections.


title:
Higgs mass and b to s gamma constraints on SUSY models with no-scale
  boundary condition

abstract:
  No-scale structure of the Kahler potential is obtained in many types of
supersymmetric models. In this paper, phenomenological aspects of these models
are investigated with special attention to the current Higgs mass bound at LEP
and b \to s \gamma result at the CLEO. When the boundary condition is given at
the GUT scale and gaugino masses are universal at this scale, very narrow
parameter region is allowed only for positive Higgsino mass region if R-parity
is conserved. The negative Higgsino mass case is entirely excluded. On the
other hand, relatively large parameter region is allowed when the boundary
condition is given above the GUT scale, and Tevatron can discover SUSY signals
for the positive Higgs mass case. The no-scale models with Wino, Higgsino or
sneutrino LSP are also considered. We show that the Higgs mass constraint is
important for the Higgsino LSP case, which requires the LSP mass to be larger
than about 245 GeV.


title:
Letting Real-Virtual Cancellations Happen by Themselves in QCD
  Calculations

abstract:
  Calculations of observables in quantum chromodynamics are typically performed
using a method that combines numerical integrations over the momenta of final
state particles with analytical integrations over the momenta of virtual
particles. I review a method for performing all of the integrations
numerically. In this method, the real-virtual cancellations happen inside the
integrals -- simply because they are built into the Feynman rules. I indicate
promising topics for further research on this subject.


title: Calculation of master integrals by difference equations

abstract:
  In this paper we describe a new method of calculation of master integrals
based on the solution of systems of difference equations in one variable. An
explicit example is given, and the generalization to arbitrary diagrams is
described. As example of application of the method, we have calculated the
values of master integrals for single-scale massive three-loop vacuum diagrams,
three-loop self-energy diagrams, two-loop vertex diagrams and two-loop box
diagrams.


title:
High-precision calculation of multi-loop Feynman integrals by difference
  equations

abstract:
  We describe a new method of calculation of generic multi-loop master
integrals based on the numerical solution of systems of difference equations in
one variable. We show algorithms for the construction of the systems using
integration-by-parts identities and methods of solutions by means of expansions
in factorial series and Laplace's transformation. We also describe new
algorithms for the identification of master integrals and the reduction of
generic Feynman integrals to master integrals, and procedures for generating
and solving systems of differential equations in masses and momenta for master
integrals. We apply our method to the calculation of the master integrals of
massive vacuum and self-energy diagrams up to three loops and of massive vertex
and box diagrams up to two loops. Implementation in a computer program of our
approach is described. Important features of the implementation are: the
ability to deal with hundreds of master integrals and the ability to obtain
very high precision results expanded at will in the number of dimensions.


title:
Lax-Phillips Scattering Theory of a Relativistic Quantum Field
  Theoretical Lee-Friedrichs Model and Lee-Oehme-Yang-Wu Phenomenology

abstract:
  The one-channel Wigner-Weisskopf survival amplitude may be dominated by
exponential type decay in pole approximation at times not too short or too
long, but, in the two channel case, for example, the pole residues are not
orthogonal, and the pole approximation evolution does not correspond to a
semigroup (experiments on the decay of the neutral K-meson system support the
semigroup evolution postulated by Lee, Oehme and Yang, and Yang and Wu, to very
high accuracy). The scattering theory of Lax and Phillips, originally developed
for classical wave equations, has been recently extended to the description of
the evolution of resonant states in the framework of quantum theory. The
resulting evolution law of the unstable system is that of a semigroup, and the
resonant state is a well-defined funtion in the Lax-Phillips Hilbert space. In
this paper we apply this theory to relativistically covarant quantum field
theoretical form of the (soluble) Lee model. We show that this theory provides
a rigorous underlying basis for the Lee-Oehme-Yang-Wu construction.


title: Defect Formation Rates in Cosmological First-Order Phase Transitions

abstract:
  In cosmological first-order phase transitions, the progress of true-vacuum
bubbles is expected to be significantly retarded by the interaction between the
bubble wall and the hot plasma. It has been claimed that this leads to a
significant reduction in the number of topological defects formed per bubble,
as a result of phase equilibration between bubbles. This claim has been
verified for spontaneously-broken global symmetries. We perform a series of
simulations of complete phase transitions in the 2+1-dimensional U(1)-Abelian
Higgs model, for a range of bubble wall velocities, in order to obtain a
quantitative measure of the effect of bubble wall speed on the number density
of topological defects. We find that the number of defects formed is i)
significantly lower in the local than the global case and ii) decreases
exponentially as a function of wall velocity. Slow-moving bubbles also lead,
however, to the nucleation of more bubbles before the phase transition is
complete. Our simulations show that this is in fact the dominant effect, and so
we predict {\em more} defects per unit volume as a result of the sub-luminal
bubble wall terminal velocity.