title: What simplified models say about unitarity and gravitational collapse

abstract:
  This paper is an extended version of a talk at the conference Constrained
Dynamics and Quantum Gravity QG99. It reviews some work on the quantum collapse
of the spherically symmetric gravitating thin shell of zero rest mass. Recent
results on Kucha\v{r} decomposition are applied. The constructed version of
quantum mechanics is unitary, although the shell falls under its Schwarzschild
radius if its energy is high enough. Rather that a permanent black hole,
something like a transient black and white hole pair seems to be created in
such a case.


title: Gravitational waves from the r-modes of rapidly rotating neutron stars

abstract:
  Since the last Amaldi meeting in 1997 we have learned that the r-modes of
rapidly rotating neutron stars are unstable to gravitational radiation reaction
in astrophysically realistic conditions. Newborn neutron stars rotating more
rapidly than about 100Hz may spin down to that frequency during up to one year
after the supernova that gives them birth, emitting gravitational waves which
might be detectable by the enhanced LIGO interferometers at a distance which
includes several supernovae per year. A cosmological background of these events
may be detectable by advanced LIGO. The spins (about 300Hz) of neutron stars in
low-mass x-ray binaries may also be due to the r-mode instability (under
different conditions), and some of these systems in our galaxy may also produce
detectable gravitational waves--see the review by G. Ushomirsky in this volume.
Much work is in progress on developing our understanding of r-mode astrophysics
to refine the early, optimistic estimates of the detectability of the
gravitational waves.


title: Gravitational Collapse with a Cosmological Constant

abstract:
  We consider the effect of a positive cosmological constant on spherical
gravitational collapse to a black hole for a few simple, analytic cases. We
construct the complete Oppenheimer-Snyder-deSitter (OSdS) spacetime, the
generalization of the Oppenheimer-Snyder solution for collapse from rest of a
homogeneous dust ball in an exterior vacuum. In OSdS collapse, the cosmological
constant may affect the onset of collapse and decelerate the implosion
initially, but it plays a diminishing role as the collapse proceeds. We also
construct spacetimes in which a collapsing dust ball can bounce, or hover in
unstable equilibrium, due to the repulsive force of the cosmological constant.
We explore the causal structure of the different spacetimes and identify any
cosmological and black hole event horizons which may be present.


title: Cohomogeneity-one Einstein-Weyl structures : a local approach

abstract:
  We analyse in a systematic way the (non-)compact n-dimensional Einstein Weyl
spaces equipped with a cohomogeneity-one metric. With no compactness
hypothesis, we prove that, as soon as the (n-1)-dimensional space is an
homogeneous reductive Riemannian space with an unimodular group of left-acting
isometries G
  1)a non-exact Einstein-Weyl stucture may exist only if the (n-1)-dimensional
homogeneous space G/H contains a non trivial subgroup H' that commutes with the
isotropy subgroup H,
  2) the extra isometry due to this Killing vector corresponds to the
right-action of one of the generators of the algebra of the subgroup H'.
  We also prove that the subclass with a one-dimensional subgroup H'
corresponds to n-dimensional Riemannian locally conformally K\"ahler metrics,
the (n-2)-dimensional space G/(HxH') being an arbitrary compact symmetric
K\"ahler coset space.


title:
Period-doubling bifurcation in strongly anisotropic Bianchi I quantum
  cosmology

abstract:
  We solve the Wheeler-DeWitt equation for the minisuperspace of a cosmological
model of Bianchi type I with a minimally coupled massive scalar field $\phi$ as
source by generalizing the calculation of Lukash and Schmidt [1]. Contrarily to
other approaches we allow strong anisotropy. Combining analytical and numerical
methods, we apply an adiabatic approximation for $\phi$, and as new feature we
find a period-doubling bifurcation. This bifurcation takes place near the
cosmological quantum boundary, i.e., the boundary of the quasiclassical region
with oscillating $\psi$-function where the WKB-approximation is good. The
numerical calculations suggest that such a notion of a ``cosmological quantum
boundary'' is well-defined, because sharply beyond that boundary, the
WKB-approximation is no more applicable at all. This result confirms the
adequateness of the introduction of a cosmological quantum boundary in quantum
cosmology.


title: Generalized Chen-Wu type cosmological model

abstract:
  Recent measurements require modifications in conventional cosmology by way of
introducing components other than ordinary matter into the total energy density
in the universe. On the basis of some dimensional considerations in line with
quantum cosmology, Chen and Wu [W. Chen and Y. Wu, Phys. Rev. D 41, 695 (1990)]
have argued that an additional component, which corresponds to an effective
cosmological constant $\Lambda$ must vary as a^{-2} in the classical era. Their
decaying-$\Lambda$ model assumes inflation and yields a value for q_{0}, which
is not compatible with observations. We generalize this model by arguing that
the Chen-Wu ansatz is applicable to the total energy density of the universe
and not to $\Lambda$ alone. The resulting model, which has a coasting evolution
(i.e., $a \propto t$), is devoid of the problems of horizon, flatness,
monopole, cosmological constant, size, age and generation of density
perturbations. However, to avoid serious contradictions with big bang
nucleosynthesis, the model has to make the predictions $\Omega_{m} = 4/3$ and
$\Omega_{\Lambda}=2/3$, which in turn are at variance with current
observational values.


title:
Weak-field approximation of a scalar theory of gravitation and some
  remarks on the propagation effects of gravity

abstract:
  A simple example is given of the implementation of the usual method of
asymptotic expansions for weak gravitational fields. A scalar, preferred-frame
theory of gravitation is considered, but the method is general. Two kinds of
asymptotic expansion are a priori possible: "post-Newtonian" (PN) or
"post-Minkowskian", the latter allowing to account directly for propagation
effects. However, it is shown that only the PN asymptotic expansion is
compatible with the Newtonian limit. It is also shown that, in the scalar
theory, there is no non-Newtonian effect (in particular, no propagation effect)
up to the second order, i.e., the order 1/c^2.


title:
Non-Singular Cosmological Models in String Gravity with Second Order
  Curvature Corrections

abstract:
  We investigate FRW cosmological solutions in the theory of modulus field
coupled to gravity through a Gauss-Bonnet term. The explicit analytical forms
of nonsingular asymptotics are presented for power-law and exponentially steep
modulus coupling functions. We study the influence of modulus field potential
on these asymptotical regimes and find some forms of the potential which do not
destroy the nonsingular behavior. In particular, we obtain that exponentially
steep coupling functions arising from the string theory do not allow
nonsingular past asymptotic unless modulus field potential tends to zero for
modulus field $\psi \to \pm \infty$. Finally, the modification of the chaotic
dynamics in the closed FRW universe due to presence of the Gauss-Bonnet term is
discussed.


title:
On de Sitter deflationary cosmology from the spin-torsion primordial
  fluctuations and COBE data

abstract:
  Fluctuations on de Sitter solution of Einstein-Cartan field equations are
obtained in terms of the matter density primordial density fluctuations and
spin-torsion density and matter density fluctuations obtained from COBE data.
Einstein-de Sitter solution is shown to be unstable even in the absence of
torsion.The spin-torsion density fluctuation to generate a deflationary phase
is computed from the COBE data.


title: Inflation, extra dimensions and Omega sub Lambda approximately = 1

abstract:
  An N + 1 dimensional quantum mechanical model for the origin of the universe
results in a 58 e-fold inflation and a cosmological constant/vacuum energy
density of the same order of magnitude as the critical density.


title:
Different approaches to the study of the gravitational radiation emitted
  by astrophysical sources

abstract:
  Stars and black holes are sources of gravitational radiation in many phases
of their life, and the signals they emit exhibit features that are
characteristic of the generating process. Emitted since the beginning of star
formation, these signals also contribute to create a stochastic background of
gravitational waves. We shall show how the spectral properties of this
background can be estimated in terms of the energy spectrum of each single
event and of the star formation rate history, which is now deducible from
astronomical observations. We shall further discuss the process of scattering
of masses by stars and black holes, showing that, unlike black holes, stars
emit signals that carry a clear signature of the nature of the source.


title:
Can the post-Newtonian gravitational waveform of an inspiraling binary
  be improved by solving the energy balance equation numerically?

abstract:
  The detection of gravitational waves from inspiraling compact binaries using
matched filtering depends crucially on the availability of accurate template
waveforms. We determine whether the accuracy of the templates' phasing can be
improved by solving the post-Newtonian energy balance equation numerically,
rather than (as is normally done) analytically within the post-Newtonian
perturbative expansion. By specializing to the limit of a small mass ratio, we
find evidence that there is no gain in accuracy.


title: Continuous Time in Consistent Histories

abstract:
  We discuss the case of histories labelled by a continuous time parameter in
the {\em History Projection Operator} consistent-histories quantum theory. We
describe how the appropriate representation of the history algebra may be
chosen by requiring the existence of projection operators that represent
propositions about time averages of the energy. We define the action operator
for the consistent histories formalism, as the quantum analogue of the
classical action functional, for the simple harmonic oscillator case. We show
that the action operator is the generator of two types of time transformations
that may be related to the two laws of time-evolution of the standard quantum
theory: the `state-vector reduction' and the unitary time-evolution. We
construct the corresponding classical histories and demonstrate the relevance
with the quantum histories; we demonstrate how the requirement of the temporal
logic structure of the theory is sufficient for the definition of classical
histories. Furthermore, we show the relation of the action operator to the
decoherence functional which describes the dynamics of the system. Finally, the
discussion is extended to give a preliminary account of quantum field theory in
this approach to the consistent histories formalism.


title:
Histories quantisation of parameterised systems: I. Development of a
  general algorithm

abstract:
  We develop a new algorithm for the quantisation of systems with first-class
constraints. Our approach lies within the (History Projection Operator)
continuous-time histories quantisation programme. In particular, the
Hamiltonian treatment (either classical or quantum) of parameterised systems is
characterised by the loss of the notion of time in the space of true degrees of
freedom (i.e. the `problem of time'). The novel temporal structure of the HPO
theory (two laws of time transformation that distinguish between the temporal
logical structure and the dynamics) persists after the imposition of the
constraints, hence the problem of time does not arise. We expound the algorithm
for both the classical and quantum cases and apply it to simple models.


title: Massless scalar fields and topological black holes

abstract:
  The exact static solutions in the higher dimensional Einstein-Maxwell-Klein-
Gordon theory are investigated. With the help of the methods developed for the
effective dilaton type gauge gravity models in two dimensions, we find new
spherically and hyperbolically symmetric solutions which generalize the four
dimensional configurations of Dereli-Eris. We show that, like in four
dimensions, the non-trivial scalar field yields, in general, a naked
singularity. The new solutions are compared with the higher dimensional
Brans-Dicke black hole type solutions.


title: 2+1-dimensional black holes with momentum and angular momentum

abstract:
  Exact solutions of Einstein's equations in 2+1-dimensional anti-de Sitter
space containing any number of black holes are described. In addition to the
black holes these spacetimes can possess ``internal'' structure. Accordingly
the generic spacetime of this type depends on a large number of parameters.
Half of these can be taken as mass parameters, and the rest as the conjugate
(angular) momenta. The time development and horizon structure of some of these
spacetimes are sketched.


title: "Massive" vector field in de Sitter space

abstract:
  We present in this paper a covariant quantization of the ``massive'' vector
field on de Sitter (dS) space based on analyticity in the complexified
pseudo-Riemanian manifold. The correspondence between unitary irreducible
representations of the de Sitter group and the field theory on de Sitter
space-time is essential in our approach. We introduce the Wightman-G\"arding
axiomatic for vector field on dS space. The Hilbert space structure and the
unsmeared field operators $K_\alpha(x)$ are also defined. This work is in the
direct continuation of previous one concerning the scalar and the spinor cases.


title: Anisotropic 'hairs' in string cosmology

abstract:
  In this letter we investigate whether the isotropy problem is naturally
solved in inflationary cosmologies inspired by string theory, so called
pre-big-bang cosmologies. We find that, in contrast to what happens in the more
common 'potential inflation' models, initial anisotropies do not decay during
pre-big-bang inflation.


title: The spinor field in Rindler spacetime: an analysis of the Unruh effect

abstract:
  We analyse the quantization procedure of the spinor field in the Rindler
spacetime, showing the boundary conditions that should be imposed to the field,
in order to have a well posed theory. We then investigate the relationship
between this construction and the usual one in Minkowski spacetime. This leads
to the concept of "Unruh effect", that is the thermal nature of the Minkowski
vacuum state from the point of view of an accelerated observer. It is
demostrated that the two constructions are qualitatively different and can not
be compared and consequently the conventional interpretation of the Unruh
effect is questionable.


title: Selection Rules in Minisuperspace Quantum Cosmology

abstract:
  The existence of a Noether symmetry for a given minisuperspace cosmological
model is a sort of selection rule to recover classical behaviours in cosmic
evolution since oscillatory regimes for the wave function of the universe come
out. The so called Hartle criterion to select correlated regions in the
configuration space of dynamical variables can be directly connected to the
presence of a Noether symmetry and we show that such a statement works for
generic extended theories of gravity in the framework of minisuperspace
approximation. Examples and exact cosmological solutions are given for
nonminimally coupled and higher--order theories.


title:
Higher-Order Corrections to the Effective Gravitational Action from
  Noether Symmetry Approach

abstract:
  Higher-order corrections of Einstein-Hilbert action of general relativity can
be recovered by imposing the existence of a Noether symmetry to a class of
theories of gravity where Ricci scalar R and its d'Alembertian $\Box R$ are
present. In several cases, it is possible to get exact cosmological solutions
or, at least, to simplify dynamics by recovering constants of motion. The main
result is that a Noether vector seems to rule the presence of higher-order
corrections of gravitaty.


title:
Gauge group and reality conditions in Ashtekar's complex formulation of
  canonical gravity

abstract:
  We discuss reality conditions and the relation between spacetime
diffeomorphisms and gauge transformations in Ashtekar's complex formulation of
general relativity. We produce a general theoretical framework for the
stabilization algorithm for the reality conditions, which is different from
Dirac's method of stabilization of constraints. We solve the problem of the
projectability of the diffeomorphism transformations from
configuration-velocity space to phase space, linking them to the reality
conditions. We construct the complete set of canonical generators of the gauge
group in the phase space which includes all the gauge variables. This result
proves that the canonical formalism has all the gauge structure of the
Lagrangian theory, including the time diffeomorphisms.


title: Gauge Transformations in Einstein-Yang-Mills Theories

abstract:
  We discuss the relation between spacetime diffeomorphisms and gauge
transformations in theories of the Yang-Mills type coupled with Einstein's
General Relativity. We show that local symmetries of the Hamiltonian and
Lagrangian formalisms of these generally covariant gauge systems are equivalent
when gauge transformations are required to induce transformations which are
projectable under the Legendre map. Although pure Yang-Mills gauge
transformations are projectable by themselves, diffeomorphisms are not. Instead
the projectable symmetry group arises from infinitesimal
diffeomorphism-inducing transformations which must depend on the lapse function
and shift vector of the spacetime metric plus associated gauge transformations.
Our results are generalizations of earlier results by ourselves and by
Salisbury and Sundermeyer.


title: The gauge group in the real triad formulation of general relativity

abstract:
  We construct explicitly generators of projectable four-dimensional
diffeomorphisms and triad rotation gauge symmetries in a model of vacuum
gravity where the fundamental dynamical variables in a Palatini formulation are
taken to be a lapse, shift, densitized triad, extrinsic curvature, and the
time-like components of the Ricci rotation coefficient. Time-foliation-altering
diffeomorphisms are not by themselves projectable under the Legendre
transformations. They must be accompanied by a metric- and triad-dependent
triad rotation. The phase space on which these generators act includes all of
the gauge variables of the model.


title:
Curvature Inheritance Symmetry In Riemannian Spaces with Applications to
  String Cloud and String Fluids

abstract:
  We study, in this paper, curvature inheritance symmetry (CI),
$\pounds_{\xi}R_{bcd}^{a}=2\alpha R_{bcd}^{a}$, where $\alpha $ is a scalar
function, for string cloud and string fluid in the context of general
relativity. Also, we have obtained some result when a proper CI (i.e., $\alpha
\neq 0$) is also a conformal Killing vector.


title: Schwarzschild Field with Maximal Acceleration Corrections

abstract:
  We consider a model in which accelerated particles experience line--elements
with maximal acceleration corrections. When applied to the Schwarzschild
metric, the effective field experienced by accelerated test particles contains
corrections that vanish in the limit $\hbar\to 0$, but otherwise affect the
behaviour of matter greatly. A new effect appears in the form of a spherical
shell, external to the Schwarzschild sphere, impenetrable to classical
particles.


title: K-causality and degenerate spacetimes

abstract:
  The causal relation $K^+$ was introduced by Sorkin and Woolgar to extend the
standard causal analysis of $C^2$ spacetimes to those that are only $C^0$. Most
of their results also hold true in the case of spacetimes with degeneracies. In
this paper we seek to examine $K^+$ explicitly in the case of Lorentzian
topology changing Morse spacetimes containing isolated degeneracies. We first
demonstrate some interesting features of this relation in globally Lorentzian
spacetimes. In particular, we show that $K^+$ is robust and that it coincides
with the Seifert relation when the spacetime is stably causal. Moreover, the
Hawking and Sachs characterisation of causal continuity translates into a
natural expression in terms of $K^+$ for general spacetimes. We then examine
$K^+$ in topology changing Morse spacetimes both with and without the
degeneracies and find further characterisations of causal continuity.


title: Tetrad Gravity and Dirac's Observables

abstract:
  Talk given at the Conference ``Constrained Dynamics and Quantum Gravity 99'',
Villasimius (Sardinia, Italy), September 13-17, 1999


title:
Dynamical invariants for general relativistic two-body systems at the
  third post-Newtonian approximation

abstract:
  We extract all the invariants (i.e. all the functions which do not depend on
the choice of phase-space coordinates) of the dynamics of two point-masses, at
the third post-Newtonian (3PN) approximation of general relativity. We start by
showing how a contact transformation can be used to reduce the 3PN higher-order
Hamiltonian derived by Jaranowski and Sch\"afer to an ordinary Hamiltonian. The
dynamical invariants for general orbits (considered in the center-of-mass
frame) are then extracted by computing the radial action variable
$\oint{p_r}dr$ as a function of energy and angular momentum. The important case
of circular orbits is given special consideration. We discuss in detail the
plausible ranges of values of the two quantities $\oms$, $\omk$ which
parametrize the existence of ambiguities in the regularization of some of the
divergent integrals making up the Hamiltonian. The physical applications of the
invariant functions derived here (e.g. to the determination of the location of
the last stable circular orbit) are left to subsequent work.


title: Energy Distribution in Melvin's Magnetic Universe

abstract:
  We use the energy-momentum complexes of Landau and Lifshitz and Papapetrou to
obtain the energy distribution in Melvin's magnetic universe. For this
space-time we find that these definitions of energy give the same and
convincing results. The energy distribution obtained here is the same as we
obtained earlier for the same space-time using the energy-momentum complex of
Einstein. These results uphold the usefulness of the energy-momentum complexes.


title: Quantization of Gravity: Yet Another Way

abstract:
  Recently proposed quantization in field theory based on an analogue of
Hamiltonian formulation which treats space and time on equal footing (the
so-called De Donder-Weyl theory) is applied to General Relativity in metric
variables. We formulate a covariant analogue of the Schroedinger equation for
the wave function of space-time and metric variables and a supplementary
``bootstrap condition'' which enables us to incorporate classical metric
geometry as an approximate notion - a result of quantum averaging - in the
self-consistent with the underlying quantum dynamics way. In this sense an
independence of an arbitrarily chosen metric background is ensured.


title: Non-minimally coupled scalar fields in homogeneous universes

abstract:
  The equations governing the evolution of non-minimally coupled scalar matter
and the scale factor of a Robertson-Walker universe are derived from a
minisuperspace action. As for the minimally coupled case, it is shown that the
entire semiclassical dynamics can be retrieved from the Wheeler-DeWitt equation
via the Born-Oppenheimer reduction, which properly yields the (time-time
component of the) covariantly conserved energy-momentum tensor of the scalar
field as the source term for gravity. However, for a generic coupling, the
expectation value of the operator which evolves the matter state in time is not
equal to the source term in the semiclassical Einstein equation for the scale
factor of the universe and the difference between these two quantities is
related to the squeezing and quantum fluctuations of the matter state. We also
argue that matter quantum fluctuations become relevant in an intermediate
regime between quantum gravity and semiclassical gravity and study several
cases in detail.


title: False Vacuum Decay With Gravity in Non-Thin-Wall Limit

abstract:
  We consider a wave-function approach to the false vacuum decay with gravity
and present a new method to calculate the tunneling amplitude under the WKB
approximation. The result agrees with the one obtained by the Euclidean
path-integral method, but gives a much clearer interpretation of an instanton
(Euclidean bounce solution) that dominates the path integral. In particular,
our method is fully capable of dealing with the case of a thick wall with the
radius of the bubble comparable to the radius of the instanton, thus surpassing
the path-integral method whose use can be justified only in the thin-wall and
small bubble radius limit. The calculation is done by matching two WKB wave
functions, one with the final state and another with the initial state, with
the wave function in the region where the scale factor of the metric is
sufficiently small compared with the inverse of the typical energy scale of the
field potential at the tunneling. The relation of the boundary condition on our
wave function for the false vacuum decay with Hartle-Hawking's no-boundary
boundary condition and Vilenkin's tunneling boundary condition on the wave
function of the universe is also discussed.


title:
Post-Newtonian SPH calculations of binary neutron star coalescence. I.
  Method and first results

abstract:
  We present the first results from our Post-Newtonian (PN) Smoothed Particle
Hydrodynamics (SPH) code, which has been used to study the coalescence of
binary neutron star (NS) systems. The Lagrangian particle-based code
incorporates consistently all lowest-order (1PN) relativistic effects, as well
as gravitational radiation reaction, the lowest-order dissipative term in
general relativity. We test our code on sequences of single NS models of
varying compactness, and we discuss ways to make PN simulations more relevant
to realistic NS models. We also present a PN SPH relaxation procedure for
constructing equilibrium models of synchronized binaries, and we use these
equilibrium models as initial conditions for our dynamical calculations of
binary coalescence. Though unphysical, since tidal synchronization is not
expected in NS binaries, these initial conditions allow us to compare our PN
work with previous Newtonian results.
  We compare calculations with and without 1PN effects, for NS with stiff
equations of state, modeled as polytropes with $\Gamma=3$. We find that 1PN
effects can play a major role in the coalescence, accelerating the final
inspiral and causing a significant misalignment in the binary just prior to
final merging. In addition, the character of the gravitational wave signal is
altered dramatically, showing strong modulation of the exponentially decaying
waveform near the end of the merger. We also discuss briefly the implications
of our results for models of gamma-ray bursts at cosmological distances.


title:
Generation of the Scalar Field and Anisotropy at Quantum Creation of the
  Closed Universe

abstract:
  The behaviour of the wave function of the Universe under the barrier for
anisotropic cosmological Bianchi type IX model with account of influence of the
scalar field is explored. In view of known difficulties with interpretation of
multidimensional wave functions the method of reduction of such problems to
one-dimensional is offered. For this purpose in frameworks of semiclassical
approach the system of characteristics equations relative to one variable is
written out. This system describe a bundle of the characteristics along which
the multidimensional problem is reduced to one-dimensional one that allows to
utillize the standard interpretation of the wave function as well as for usual
Schrodinger equation. The obtained results for Bianchi type IX model are
reduced to the following statement: the Universe tunnels through the barrier
from an isotropic state with zero initial value of the scalar field and appear
in classically allowed region with small anisotropy that is necessary for
providing of long-lived inflation for deriving the Universe such as ours.


title: Deep Surveys of Massive Black Holes with LISA

abstract:
  Massive black hole binary systems are among the most interesting sources for
the Laser Interferometer Space Antenna (LISA); gravitational radiation emitted
during the last year of in-spiral could be detectable with a very large
signal-to-noise ratio for sources at cosmological distance. Here we discuss the
impact of LISA for astronomy and cosmology; we review our present understanding
of the relevant issues, and highlight open problems that deserve further
investigations.


title: Gravitational Global Monopoles with Horizons

abstract:
  We give arguments for the existence of ``radial excitations'' of
gravitational global monopoles with any number of zeros of the Higgs field and
present numerical results for solutions with up to two zeros. All these
solutions possess a de Sitter like cosmological horizon, outside of which they
become singular. In addition we study corresponding static ``hairy'' black hole
solutions, representing black holes sitting inside a global monopole core. In
particular, we determine their existence domains as a function of their horizon
radius rh.


title:
Small Perturbations in General Relativity: Tensor Harmonics of Arbitrary
  Symmetry

abstract:
  We develop a method for constructing of the basic functions with witch to
expand small perturbations of space-time in General Relativity. The method
allows to obtain the tensor harmonics for perturbations of the background
space-time admitting an arbitrary group of isometry, and to split the
linearized Einstein equations into the irreducible combinations. The essential
point of the work is the construction of the generalized Casimir operator for
the underlying group, which is defined not only on vector but also on tensor
fields. It is used to construct the basic functions for spaces of tensor
representations of the background metric's group of isometry. The method, being
general, is applied here to construction of the basic functions for the case of
the three-parameter group of isometry G_3 acting on the two-dimensional
non-isotropic surface of transitivity. As quick illustrations of the method we
consider the well-known particular cases: cylindrical harmonic for the flat
space-time, and Regge-Wheller spherical harmonics for the Schwarzschild metric.


title: Using binary stars to bound the mass of the graviton

abstract:
  Interacting white dwarf binary star systems, including helium cataclysmic
variable (HeCV) systems, are expected to be strong sources of gravitational
radiation, and should be detectable by proposed space-based laser
interferometer gravitational wave observatories such as LISA. Several HeCV star
systems are presently known and can be studied optically, which will allow
electromagnetic and gravitational wave observations to be correlated.
Comparisons of the phases of a gravitational wave signal and the orbital light
curve from an interacting binary white dwarf star system can be used to bound
the mass of the graviton. Observations of typical HeCV systems by LISA could
potentially yield an upper bound on the inverse mass of the graviton as strong
as $h/m_{g} = \lambda_{g} > 1 \times 10^{15}$ km ($m_{g} < 1 \times 10^{-24}$
eV), more than two orders of magnitude better than present solar system derived
bounds.


title: Aspects of black hole entropy

abstract:
  There have been many attempts to understand the statistical origin of
black-hole entropy. Among them, entanglement entropy and the brick wall model
are strong candidates. In this paper, first, we show that the entanglement
approach reduces to the brick wall model when we seek the maximal entanglement
entropy. After that, the stability of the brick wall model is analyzed in a
rotating background. It is shown that in the Kerr background without horizon
but with an inner boundary a scalar field has complex-frequency modes and that,
however, the imaginary part of the complex frequency can be small enough
compared with the Hawking temperature if the inner boundary is sufficiently
close to the horizon, say at a proper altitude of Planck scale. Hence, the
brick wall model is well defined even in a rotating background if the inner
boundary is sufficiently close to the horizon. These results strongly suggest
that the entanglement approach is also well defined in a rotating background.


title: On de Sitter gravitationally from the spin-torsion primordial density

abstract:
  Fluctuations on de Sitter solution of Einstein-Cartan field equations are
obtained in terms of the matter density primordial density fluctuations and
spin-torsion density and matter density fluctuations obtained from COBE data.
Einstein-de Sitter solution is shown to be unstable even in the absence of
torsion.The spin-torsion density fluctuation is simply computed from the
Einstein-Cartan equations and from COBE data.


title:
A study of the angular size-redshift relation for models in which
  $\Lambda$ decays as the energy density

abstract:
  By modifying the Chen and Wu ansatz, we have investigated some Friedmann
models in which $\Lambda$ varies as $\rho$. In order to test the consistency of
the models with observations, we study the angular size - redshift relation for
256 ultracompact radio sources selected by Jackson and Dodgson. The angular
sizes of these sources were determined by using very long-baseline
interferometry in order to avoid any evolutionary effects. The models fit the
data very well and require an accelerating universe with a positive
cosmological constant. Open, flat and closed models are almost equally
probable, though the open model provides a comparatively better fit to the
data. The models are found to have intermediate density and imply the existence
of dark matter, though not as much as in the canonical Einstein-de Sitter
model.


title: A dark energy model resulting from a Ricci symmetry revisited

abstract:
  Observations of supernovae of type Ia require dark energy (some unknown
exotic \emph{`matter'} of negative pressure) to explain their unexpected
faintness. Whereas the simplest and most favoured candidate of dark energy, the
Einsteinian cosmological constant, is about 120 orders of magnitude smaller
than the theoretically predicted value. Motivated by this problem, a number of
models of dynamically decaying dark energy have been proposed by considering
different phenomenological laws or potentials of the scalar field, which are
more or less ad-hoc. However, it is more advisable to consider the symmetry
properties of spacetime rather than the ad-hoc assumptions.
  In this view, we consider a model of Robertson-Walker cosmology emerging from
a Ricci symmetry which provides consistently an evolving dark energy. We test
the model for the recent supernovae Ia data, as well as, the ultracompact radio
sources data compiled by Jackson and Dodgson. The model fits the data very
well.


title: Partially locally rotationally symmetric perfect fluid cosmologies

abstract:
  We show that there are no new consistent cosmological perfect fluid solutions
when in an open neighbourhood ${\cal U}$ of an event the fluid kinematical
variables and the electric and magnetic Weyl curvature are all assumed
rotationally symmetric about a common spatial axis, specialising the Weyl
curvature tensor to algebraic Petrov type D. The consistent solutions of this
kind are either locally rotationally symmetric, or are subcases of the Szekeres
dust models. Parts of our results require the assumption of a barotropic
equation of state. Additionally we demonstrate that local rotational symmetry
of perfect fluid cosmologies follows from rotational symmetry of the Riemann
curvature tensor and of its covariant derivatives only up to second order, thus
strengthening a previous result.


title: Excitation of Kaluza-Klein gravitational mode

abstract:
  We investigate excitation of Kaluza-Klein modes due to the parametric
resonance caused by oscillation of radius of compactification. We consider a
gravitational perturbation around a D-dimensional spacetime, which we
compactify on a (D-4)-sphere to obtain a 4-dimensional theory. The perturbation
includes the so-called Kaluza-Klein modes, which are massive in 4-dimension, as
well as zero modes, which is massless in 4-dimension. These modes appear as
scalar, vector and second-rank symmetric tensor fields in the 4-dimensional
theory. Since Kaluza-Klein modes are troublesome in cosmology, quanta of these
Kaluza-Klein modes should not be excited abundantly. However, if radius of
compactification oscillates, then masses of Kaluza-Klein modes also oscillate
and, thus, parametric resonance of Kaluza-Klein modes may occur to excite their
quanta. In this paper we consider part of Kaluza-Klein modes which correspond
to massive scalar fields in 4-dimension and investigate whether quanta of these
modes are excited or not in the so called narrow resonance regime of the
parametric resonance. We conclude that at least in the narrow resonance regime
quanta of these modes are not excited so catastrophically.


title:
Monodromy transform approach to solution of the Ernst equations in
  General Relativity

abstract:
  The approach, referred to as "monodromy transform", provides some general
base for solution of all known integrable space - time symmetry reductions of
Einstein equations for the case of pure vacuum gravitational fields, in the
presence of gravitationally interacting massless fields, as well as for some
string theory induced gravity models. In this communication we present the key
points of this approach, applied to Einstein equations for vacuum and to
Einstein - Maxwell equations for electrovacuum fields in the cases, reducible
to the known Ernst equations. Definition of the monodromy data, formulation and
solution of the direct and inverse problems of the monodromy transform, a proof
of existence and uniqueness of their solutions, the structure of the basic
linear singular integral equations and their regularizations, which lead to the
equations of (quasi-)Fredholm type are also discussed. A construction of
general local solution of these equations is given in terms of homogeneously
convergent functional series.


title: Multi-centered Solutions with a (very special) Warped Compactification

abstract:
  We find an exact solution for multi-black strings in the brane world with
warped compactification.


title: Path integral in the simplest Regge calculus model

abstract:
  The simplest (3+1)D Regge calculus model (with three-dimensional discrete
space and continuous time) is considered which describes evolution of the
simplest closed two-tetrahedron piecewise flat manifold in the continuous time.
The measure in the path integral which describes canonical quantisation of the
model in terms of area bivectors and connections as independent variables is
found. It is shown that selfdual-antiselfdual splitting of the variables
simplifies the integral although does not admit complete separation of
(anti-)selfdual sector.


title: The simplest Regge calculus model in the canonical form

abstract:
  Dynamics of a Regge three-dimensional (3D) manifold in a continuous time is
considered. The manifold is closed consisting of the two tetrahedrons with
identified corresponding vertices. The action of the model is that obtained via
limiting procedure from the general relativity (GR) action for the completely
discrete 4D Regge calculus. It closely resembles the continuous general
relativity action in the Hilbert-Palatini (HP) form but possesses finite number
of the degrees of freedom. The canonical structure of the theory is described.
Central point is appearance of the new relations with time derivatives not
following from the Lagrangian but serving to ensure completely discrete 4D
Regge calculus origin of the system. In particular, taking these into account
turns out to be necessary to obtain the true number of the degrees of freedom
being the number of linklengths of the 3D Regge manifold at a given moment of
time.


title: An approximate binary-black-hole metric

abstract:
  An approximate solution to Einstein's equations representing two
widely-separated non-rotating black holes in a circular orbit is constructed by
matching a post-Newtonian metric to two perturbed Schwarzschild metrics. The
spacetime metric is presented in a single coordinate system valid up to the
apparent horizons of the black holes. This metric could be useful in numerical
simulations of binary black holes. Initial data extracted from this metric have
the advantages of being linked to the early inspiral phase of the binary
system, and of not containing spurious gravitational waves.


title:
Entropy Production and Thermodynamic Arrow of Time in a Recollapsing
  Universe

abstract:
  We investigate the thermodynamic arrow of time in a time-symmetrically
recollapsing universe by calculating quantum mechanically the entropy
production of a massive scalar field. It is found that even though the
Hamiltonian has a time-reversal symmetry with respect to the maximum expansion
of the universe, the entropy production is generic and the total entropy of the
scalar field increases monotonically. We conclude that the thermodynamic arrow
of time is a universal phenomenon even in the expanding and subsequently
recollapsing universe due to the parametric interaction of matter field with
gravity.


title: Gravitational Collapse and Calogero Model

abstract:
  We study the analytic structure of the S-matrix which is obtained from the
reduced Wheeler-DeWitt wave function describing spherically symmetric
gravitational collapse of massless scalar fields. The simple poles in the
S-matrix occur in the Euclidean spacetime, and the Euclidean Wheeler-DeWitt
equation is a variant of the Calogero models, which is discussed in connection
with conformal mechanics and a quantum instanton.


title:
The algebraic structure of a cosmological term in spherically symmetric
  solutions

abstract:
  We propose to describe the dynamics of a cosmological term in the spherically
symmetric case by an r-dependent second rank symmetric tensor invariant under
boosts in the radial direction. This proposal is based on the Petrov
classification scheme and Einstein field equations in the spherically symmetric
case. The inflationary equation of state p=-\rho is satisfied by the radial
pressure. The tangential pressure is calculated from the conservation equation
(the contracted Bianchi identity).


title: Proposed astrophysical test of Lorentz invariance

abstract:
  Working in the context of a Lorentz-violating extension of the standard model
we show that estimates of Lorentz symmetry violation extracted from ultra-high
energy cosmic rays beyond the Greisen-Kuzmin-Zatsepin (GZK) cutoff allow for
setting bounds on parameters of that extension. Furthermore, we argue that a
correlated measurement of the difference in the arrival time of gamma-ray
photons and neutrinos emitted from active galactic nuclei or gamma-ray bursts
may provide a signature of possible violation of Lorentz symmetry. We have
found that this time delay is energy independent, however it has a dependence
on the chirality of the particles involved. We also briefly discuss the known
settings where the mechanism for spontaneous violation of Lorentz symmetry in
the context of string/M-theory may take place.


title: Black Hole Entropy from Horizon Conformal Field Theory

abstract:
  String theory and ``quantum geometry'' have recently offered independent
statistical mechanical explanations of black hole thermodynamics. But these
successes raise a new problem: why should models with such different
microscopic degrees of freedom yield identical results? I propose that the
asymptotic behavior of the density of states at a black hole horizon may be
determined by an underlying symmetry inherited from classical general
relativity, independent of the details of quantum gravity. I offer evidence
that a two-dimensional conformal symmetry at the horizon, with a classical
central extension, may provide the needed behavior.


title: The Thermodynamics of Black Holes

abstract:
  We review the present status of black hole thermodynamics. Our review
includes discussion of classical black hole thermodynamics, Hawking radiation
from black holes, the generalized second law, and the issue of entropy bounds.
A brief survey also is given of approaches to the calculation of black hole
entropy. We conclude with a discussion of some unresolved open issues.


title:
A Possible Theoretical Basis for Propulsive Force Generation by Both
  Conventional and Unconventional Means

abstract:
  A possible theoretical basis is given for propulsive force generation by both
conventional and unconventional means.


title: Topological Defect Inflation

abstract:
  We address some issues of topological defect inflation. (1) We clarify the
causal structure of an inflating magnetic monopole. The spacetime diagram shows
explicitly that this model is free from the ``graceful exit'' problem, while
the monopole itself undergoes ``eternal inflation''. (2) We extend the study of
inflating topological defects to Brans-Dicke gravity. Contrary to the case of
Einstein gravity, any inflating monopole eventually shrinks and takes a stable
configuration. (3) We reanalyze chaotic inflation with a non-minimally coupled
massive scalar field. We find a new solution of domain wall inflation, which
relaxes constraints on the coupling constant for successful inflation.


title:
Generalized asymptotic structure of the ultrarelativistic Schwarzschild
  black hole

abstract:
  We discuss the asymptotic structure of the ultrarelativistic Schwarzschild
black hole. An explicit construction for a conformal boundary both at spatial
and null infinity is given together with the corresponding expressions for the
ADM and Bondi four-momenta.


title:
A CsI(Tl) Scintillating Crystal Detector for the Studies of Low Energy
  Neutrino Interactions

abstract:
  Scintillating crystal detector may offer some potential advantages in the
low-energy, low-background experiments. A 500 kg CsI(Tl) detector to be placed
near the core of Nuclear Power Station II in Taiwan is being constructed for
the studies of electron-neutrino scatterings and other keV-MeV range neutrino
interactions. The motivations of this detector approach, the physics to be
addressed, the basic experimental design, and the characteristic performance of
prototype modules are described. The expected background channels and their
experimental handles are discussed.


title: Search for the Decay B0 -> D*0 gamma

abstract:
  We report results of a search for the rare radiative decay B0 -> D*0 gamma.
Using 9.7 million BB meson pairs collected with the CLEO detector at the
Cornell Electron Storage Ring, we limit Br(B0->D*0 gamma) < 5.0 * 10^-5 at 90%
CL. This provides evidence that anomalous enhancement is absent in W-exchange
processes and that weak radiative B decays are dominated by the short-distance
b -> s gamma mechanism in the Standard Model.


title: The E791 Parallel Architecture Data Acquisition System

abstract:
  To collect data for the study of charm particle decays, we built a high speed
data acquisition system for use with the E791 magnetic spectrometer at
Fermilab. The DA system read out 24000 channels in 50 uS. Events were accepted
at the rate of 9000 per second. Eight large FIFOs were used to buffer event
segments, which were then compressed and formatted by 54 processors housed in 6
VME crates. Data was written continuously to 42 Exabyte tape drives at the rate
of 9.6 Mb/s. During the 1991 fixed target run at Fermilab, 20 billion physics
events were recorded on 24000 8 mm tapes; this 50 Tb (Terabyte) data set is now
being analyzed.


title:
Observation of D-pi Production Correlations in 500 GeV pi- - N
  Interactions

abstract:
  We study the charge correlations between charm mesons produced in 500 GeV pi-
- N interactions and the charged pions produced closest to them in phase space.
With 110,000 fully reconstructed D mesons from experiment E791 at Fermilab, the
correlations are studied as functions of the Dpi - D mass difference and of
Feynman x. We observe significant correlations which appear to originate from a
combination of sources including fragmentation dynamics, resonant decays, and
charge of the beam.


title: Observation of the Decay $K_L\to \mu^+\mu^- \gamma \gamma$

abstract:
  We have observed the decay $K_L\to \mu^+\mu^- \gamma \gamma$ at the KTeV
experiment at Fermilab. This decay presents a formidable background to the
search for new physics in $K_L\to\pi^0\mu^+\mu^-$. The 1997 data yielded a
sample of 4 signal events, with an expected background of 0.155 $\pm$ 0.081
events. The branching ratio is ${\mathcal B}(K_L\to \mu^+\mu^- \gamma \gamma$)
$ = (10.4^{+7.5}_{-5.9} {\rm (stat)} \pm 0.7 {\rm (sys)})\times 10^{-9}$ with
$m_{\gamma\gamma} \geq 1 {\rm MeV/c}^2$, consistent with a QED calculation
which predicts $(9.1\pm 0.8)\times 10^{-9}$.


title: Search for the Decay $K_L \to \pi^0 \mu^+ \mu^-$

abstract:
  We report on a search for the decay \klpimumu carried out as a part of the
KTeV experiment at Fermilab. This decay is expected to have a significant $CP$
violating contribution and a direct measurement will either support the CKM
mechanism for CP violation or point to new physics. Two events were observed in
the 1997 data with an expected background of $0.87 \pm 0.15$ events, and we set
an upper limit \BR{\klpimumu} $ <3.8 \times 10^{-10}$ at the 90% confidence
level.


title: Discovering a Light Higgs Boson with Light

abstract:
  We evaluate the prospects for detecting a non-standard light Higgs boson with
a significant branching ratio to two photons, in Run II of the Fermilab
Tevatron. We derive the reach for several channels: $2\gamma$ inclusive,
$2\gamma+1$ jet and $2\gamma+2$ jets. We present the expected Run II limits on
the branching ratio of $h\to\gamma\gamma$ as a function of the Higgs mass, for
the case of ``bosonic'', as well as ``topcolor'' Higgs bosons.


title: Highlights in Neutrino and Astroparticle Physics

abstract:
  The main highlights from the papers presented at this workshop are briefly
reviewed and discussed in a general context.


title:
Measurement of Charge Asymmetries in Charmless Hadronic in B Meson
  Decays

abstract:
  We search for CP-violating asymmetries (Acp) in the B meson decays to K+-
pi-+, K+- pi0, Ks pi+-, K+- eta', and omega pi+-. Using 9.66 million
Upsilon(4S) decays collected with the CLEO detector, the statistical precision
on Acp is in the range of \pm 0.12 to \pm 0.25 depending on decay mode. While
CP-violating asymmetries of up to \pm 0.5 are possible within the Standard
Model, the measured asymmetries are consistent with zero in all five decay
modes studied.


title:
Study of Two-Body B Decays to Kaons and Pions: Observation of B->pi+pi-,
  B-> K+-pi0, and B-> K0pi0 Decays

abstract:
  We have studied charmless hadronic decays of B mesons into two-body final
states with kaons and pions and observe three new processes with the following
branching fractions: BR(B-> pi+ pi-) = (4.3^{+1.6}_{-1.4} \pm 0.5) \times
10^{-6}, BR(B-> K0 pi0) = (14.6^{+5.9+2.4}_{-5.1-3.3}) \times 10^{-6}, and
BR(B-> K+- pi0) = (11.6^{+3.0+1.4}_{-2.7-1.3}) \times 10^{-6}. We also update
our previous measurements for the decays B->K+- pi-+ and B-> K0 pi+-.


title: Studies of Avalanche Photodiode Performance in a High Magnetic Field

abstract:
  We report the results of exposing a Hamamatsu avalanche photodiode (APD) to a
7.9 Tesla magnetic field. The effect of the magnetic field on the gain of the
APD is shown and discussed. We find APD gain to be unaffected in the presence
of such a magnetic field.


title: Assessment and Outlook

abstract:
  My assignment at this conference is to assess where we are in high-energy
physics and speculate on where we might be going. This frees me from any
obligation to summarize all that went on here and allows me to talk just about
those topics that interest me the most at this time. I will let my prejudices
show and talk a bit about physics in general, CP violation, neutrinos,
accelerators, non-accelerator experiments, and even theory.


title:
Measurement of the B0 and B+ meson masses from B0 -> psi(') K_S and B+
  -> psi(') K+ decays

abstract:
  Using 9.6 million B meson pairs collected with the CLEO detector, we have
fully reconstructed 135 B0 -> psi(') K_S and 526 B+ -> psi(') K+ candidates
with very low background.
  We fitted the psi(')K invariant mass distributions of these B meson
candidates and measured the masses of the neutral and charged B mesons to be
M(B0)=5279.1+-0.7[stat]+-0.3[syst] MeV/c^2 and
M(B+)=5279.1+-0.4[stat]+-0.4[syst] MeV/c^2. The precision is a significant
improvement over previous measurements.


title: Recent Results from the L3 Experiment

abstract:
  A data sample corresponding to an integrated luminosity of 232pb^-1 was
collected in 1997 and 1998 by the L3 experiment at LEP in e+e- collisions at
centre-of-mass energies between 181.7GeV and 188.7GeV. Pair production of
fermions and bosons is studied and compared with the Standard Model
expectations. Events with a single detected photon or W boson are also
considered. The measurement of several Standard Model cross sections is
discussed. The presence and the magnitude of triple couplings of charged and
neutral electroweak gauge bosons is investigated. These processes are used to
probe New Physics beyond the Standard Model, including the existence of extra
spatial dimensions.


title:
Search for Nucleon Decay with Final States l+ eta, nubar eta, and nubar
  pi+,0 Using Soudan 2

abstract:
  We have searched for nucleon decay into five two-body final states using a
4.4 kiloton-year fiducial exposure of the Soudan 2 iron tracking calorimeter.
For proton decay into the fully visible final states mu+ eta and e+ eta, we
observe zero and one event, respectively, that satisfy our search criteria for
nucleon decay. The lifetime lower limits (tau/B) thus implied are 89 x 10^30
years and 81 x 10^30 years at 90% confidence level. For neutron decay into
nubar eta, we obtain the lifetime lower limit 71 x 10^30 years. Limits are also
reported for neutron decay into nubar pi0, and for proton decay into nubar pi+.


title: Direct Observation of Longitudinally Polarised W Bosons

abstract:
  The three different helicity states of W bosons, produced in the reaction
e+e- -> W+W- -> l nu q q~ are studied using leptonic and hadronic W decays at
sqrt{s}=183GeV and 189GeV. The W polarisation is also measured as a function of
the scattering angle between the W- and the direction of the e- beam. The
analysis demonstrates that W bosons are produced with all three helicities, the
longitudinal and the two transverse states. Combining the results from the two
center-of-mass energies and with leptonic and hadronic W decays, the fraction
of longitudinally polarised W bosons is measured to be 0.261 +/- 0.051(stat.)
+/- 0.016(syst.) in agreement with the expectation from the Standard Model.


title:
A study of the f0(1370), f0(1500), f0(2000) and f2(1950) observed in the
  centrally produced 4pi final states

abstract:
  The production and decay properties of the f0(1370), f0(1500), f0(2000) and
f2(1950) have been studied in central pp interactions at 450 GeV/c. The dPT,
phi and |t| distributions of these resonances are presented. For the J = 0
states, the f0(1370) and f0(2000) have similar dPT and phi dependences. These
are different to the dPT and phi dependences of the f0(980), f0(1500) and
f0(1710). For the J = 2 states the f2(1950) has different dependences to the
f2(1270) and f2'(1520). This shows that the dPT and phi dependences are not
just J phenomena.


title: Simulation of UHE muons propagation for GEANT3

abstract:
  A simulation package for the transport of high energy muons has been
developed. It has been conceived to replace the muon propagation software
modules implemented in the detector simulation program GEANT3. Here we discuss
the results achieved with our package and we check the agreement with numerical
calculations up to 10**8 GeV.


title: Brief Report from the Tevatron

abstract:
  We report on the B physics prospects from the Fermilab Tevatron, summarizing
the B physics goals of the CDF and DO experiments using their upgraded
detectors. We discuss the time schedule for completion of the detector upgrades
and summarize the current measurement of the CP violation parameter sin(2 beta)
at CDF.


title:
The Parameterized Simulation of Electromagnetic Showers in Homogeneous
  and Sampling Calorimeters

abstract:
  A general approach to a fast simulation of electromagnetic showers using
parameterizations of the longitudinal and radial profiles in homogeneous and
sampling calorimeters is described. The dependence of the shower development on
the materials used and the sampling geometry is taken into account explicitly.
Comparisons with detailed simulations of various calorimeters and with data
from the liquid argon calorimeter of the H1 experiment are made.


title:
The Transverse Momentum and Total Cross Section of E+ E- Pairs in the
  Z-Boson Region from P Anti-P Collisions at s**(1/2) = 1.8-Tev

abstract:
  The transverse momentum and total cross section of e^+e^- pairs in the
Z-boson region of 66<M_{ee}<116 GeV$/c^2$ from $p\bar{p}$ collisions at
$\sqrt{s}=1.8$ TeV are measured using 110 pb^{-1} of collisions taken by the
Collider Detector at Fermilab during 1992-1995. The total cross section is
measured to be $248 \pm 11$ pb. The differential transverse momentum cross
section is compared with calculations that match quantum chromodynamics
perturbation theory at high transverse momentum with the gluon resummation
formalism at low transverse momentum.


title: Recent Low x and Diffractive Collider Data

abstract:
  Selected recent data from collider experiments pertaining to the
understanding of QCD at low Bjorken-x are reviewed. The status of QCD and Regge
factorisation in hard diffractive interactions is discussed in terms of data
from HERA and the Tevatron. The possibility of anomalous behaviour in the
$\gamma \gamma$ total cross section is confronted with the most recent
measurements from LEP. Data from all three colliders that are sensitive to
possible BFKL effects are presented and different interpretations are
discussed.


title: Standard Model Physics at LEP

abstract:
  Selected topics on precision tests of the Standard Model of the Electroweak
and the Strong Interaction at the LEP $e^+e^-$ collider are presented,
including an update of the world summary of measurements of $\alpha_s$,
representing the state of knowledge of summer 1999. This write-up of lecture
notes consists of a reproduction of slides, pictures and tables, supplemented
by a short descriptive text and a list of relevant references.


title:
Quark Mixing Matrix Studies and Lepton Flavor Violation Searches Using
  Rare Decays of Kaons

abstract:
  I review recent results from experiments on rare decays of kaons,
concentrating on searches for lepton flavor violation (LFV) and on measurements
of quark mixing (CKM) matrix elements. The LFV results are the culmination of
15 years of experimentation at Brookhaven National Laboratory and are unlikely
to be improved upon soon. The CKM studies derive from measurements of decay
rates of charged and neutral kaons into lepton anti-lepton pairs, both with and
without a charged or neutral pion. I discuss recent results and prospects for
improved measurements that could provide an unambiguous test of the Standard
Model explanation for CP violation. This paper is the written version of a talk
presented at the Lepton-Photon Conference in August 1999.


title:
The Search for Fractional Charge Elementary Particles and Very Massive
  Particles in Bulk Matter

abstract:
  We describe our ongoing work on, and future plans for, searches in bulk
matter for fractional charge elementary particles and very massive elementary
particles. Our primary interest is in searching for such particles that may
have been produced in the early universe and may be found in the more primeval
matter available in the solar system: meteorites, material from the moon's
surface, and certain types of ancient terrestrial rocks. In the future we are
interested in examining material brought back by sample return probes from
asteroids. We will describe our experimental methods that are based on new
modifications of the Millikan liquid drop technique and modern technology:
micromachining, CCD cameras, and desktop computers. Extensions of our
experimental methods and technology allow searches for very massive charged
particles in primeval matter; particles with masses greater than 10**13 GeV. In
the first such searches carried out on earth there will be uncertainties in the
mass search range. Therefore we will also discuss the advantages of eventually
carrying out such searches directly on an asteroid.


title:
A New Method for Searching for Free Fractional Charge Particles in Bulk
  Matter

abstract:
  We present a new experimental method for searching for free fractional charge
in bulk matter; this new method derives from the traditional Millikan liquid
drop method, but allows the use of much larger drops, 20 to 100 mm in diameter,
compared to the traditional method that uses drops less than 15 mm in diameter.
These larger drops provide the substantial advantage that it is then much
easier to consistently generate drops containing liquid suspensions of powdered
meteorites and other special minerals. These materials are of great importance
in bulk searches for fractional charge particles that may have been produced in
the early universe.


title:
On the Parameterization of the Longitudinal Hadronic Shower Profiles in
  Combined Calorimetry

abstract:
  The extension of the longitudinal hadronic shower profile parameterization
which takes into account non-compensations of calorimeters and the algorithm of
the longitudinal hadronic shower profile curve making for a combined
calorimeter are suggested. The proposed algorithms can be used for data
analysis from modern combined calorimeters like in the ATLAS detector at the
LHC.


title: Laser cooling of electron beams at linear colliders

abstract:
  A method of electron beam cooling is considered which can be used for linear
colliders. The electron beam is cooled during collision with focused powerful
laser pulse. The ultimate transverse emittances are much below those achievable
by other methods. This method is especially useful for high energy gamma-gamma
colliders. In this paper we review and analyse limitations in this method, also
discuss a new method of obtaining very high laser powers required for the laser
cooling, radiation conditions and finaly present a possible scheme for the
laser cooling of electron beams.


title: High energy photon colliders

abstract:
  Using the laser backscattering method at future linear colliders one can
obtain gamma-gamma and gamma-electron colliding beams (photon colliders) with
energy and luminosity comparable to that in e^+e^- collisions. This option has
been included in the pre-conceptual designs of linear colliders and in work on
a Technical Design Report which is in progress. The physics motivation for
photon colliders is quite clear. The proof of its technical feasibility and the
search for the best solutions is of first priority now. A key element of a
photon collider is a laser with high peak power and repetition rate. One very
promising way to overcome this problem is the optical cavity approach which is
discussed in this paper. A very high gamma-gamma luminosity could be achieved
by further decreasing the beam emittances. This will be very challenging. One
possible way is laser cooling of electron beams. This method is discussed in my
second talk at this symposium. The solution to the first problem is vital for
photon colliders and provides an interesting physics program. Solution of the
second problem makes photon colliders a very powerful instrument for study of
matter, the best for study of many phenomena. How to achieve these goals is the
subject of this talk.

categories: hep-ex hep-ph physics.acc-ph physics.optics


title:
Problems and stoppers for gamma-gamma, gamma-mu, mu-p colliders using
  very high energy muons

abstract:
  It is well known that at linear e^+e^-(e^-e^-) colliders using laser
backscattering one can obtain colliding gamma-gamma, gamma-electron beams with
energy and luminosity comparable to those in e^+e^- collisions. In this paper,
it is explained why this can not be done at high energy muon colliders. Due to
several physics reasons the gamma-gamma luminosity is suppressed here by a
factor of 10^{14} ! Another option -- gamma's from a linear collider and muons
from a muon collider -- is also discussed (and has no sense either). Of course,
one can study gamma^*-muon and gamma^*-gamma^* interactions at muon colliders
in collisions with virtual photons as it is done now at e^+e^- storage rings.
Muon-proton colliders are attractive only if the proton beam is cooled and has
the same parameters as the muon beam, in which case
  L_{\mu p} \sim L_{\mu\mu}.


title: Coherent e^+e^- pair creation at high energy muon colliders

abstract:
  It is shown that at muon colliders with the energy in the region of 100 TeV
the process of coherent pair creation by the muon in the field of the opposing
beam becomes important and imposes some limitations on collider parameters.


title:
Limit on a horizontal emittance in high energy muon colliders due to
  synchrotron radiation

abstract:
  It is shown that at a 100 TeV muon collider the synchrotron radiation in the
ring will determine the minimum horizontal emittance.


title:
Some problems in plasma suppression of beam-beam interactions at muon
  colliders

abstract:
  The idea of plasma suppression of beam-beam effects at muon colliders is
discussed. It is shown that one should take into account collisions in the
plasma that were ignored before. Rough estimates show that this effect leads to
a fast ``recovery'' of the beam magnetic field. For beam parameters
characteristic for muon colliders the suppression of the magnetic component of
the beam field (1/2 of the total force) is almost absent. It is also shown that
the presence of the dense plasma (Li jet) at the interaction point leads to
enormous hadronic background (due to photo-nuclear reactions) in the detector,
about 10^{7} particles per crossing at large angles which creates serious
problems for experimentation.


title: Neutrino Mass and Oscillations

abstract:
  Current evidence for neutrino oscillation is reviewed, some areas for closer
investigation are suggested, and a plausible future experimental program is
summarized.


title:
Neutrino Oscillation Appearance Experiment using Nuclear Emulsion and
  Magnetized Iron

abstract:
  This report describes an apparatus that could be used to measure both the
identity and charge of an outgoing lepton in a charged current neutrino
interaction. This capability in a massive detector would allow the most
comprehensive set of neutrino oscillation physics measurements. By measuring
the six observable transitions between initial and final state neutrinos, one
would be able to measure all elements of the neutrino mixing matrix, as well as
search for CP violation, and matter effects. If the measured matrix is not
unitary, then one would also have an unambiguous determination of sterile
neutrinos. Emulsion is considered as the tracking medium, and different
techniques are discussed for the application of a magnetic field.


title: Confidence belts on bounded parameters

abstract:
  We show that the unified method recently proposed by Feldman and Cousins to
put confidence intervals on bounded parameters cannot avoid the possibility of
getting null results. A modified bayesian approach is also proposed (although
not advocated) which ensures no null results and proper coverage.


title: Higgs Searches at LEP2 with the ALEPH Detector

abstract:
  Data collected with the ALEPH detector at centre-of-mass energies between 130
and 189 GeV are used to search for Higgs bosons of the standard model and its
supersymmetric extensions. No evidence for a Higgs particle has been found in
256 pb^-1 of LEP2 data. Mass exclusion limits were set.


title:
A partial wave analysis of the $\pi ^0\pi ^0$ system produced in $\pi
  ^-p$ charge exchange collisions

abstract:
  A partial wave analysis of the of the $\pi ^0\pi ^0$ system produced in the
charge exchange reaction: $\pi ^-p\to \pi ^0\pi ^0n$ at an incident momentum of
$18.3 GeV/c$ is presented as a function of ${\pi ^0\pi ^0}$ invariant mass,
$m_{\pi^0\pi^0}$, and momentum transfer squared, $| {t} |$, from the incident
$\pi^-$ to the outgoing ${\pi ^0\pi ^0}$ system.


title: Physics Beyond the Standard Model

abstract:
  I briefly summarize the prospects for extending our understanding of physics
beyond the standard model within the next five years.


title:
High Precision Mass Measurements in $\Psi$ and $\Upsilon$ Families
  Revisited

abstract:
  High precision mass measurements in $\Psi$ and $\Upsilon$ families performed
in 1980-1984 at the VEPP-4 collider with OLYA and MD-1 detectors are revisited.
The corrections for the new value of the electron mass are presented. The
effect of the updated radiative corrections has been calculated for the
$J/\Psi(1S)$ and $\Psi(2S)$ mass measurements.


title:
On the possibility of radar echo detection of ultra-high energy cosmic
  ray- and neutrino-induced extensive air showers

abstract:
  We revisit and extend the analysis supporting a 60 year-old suggestion that
cosmic rays air showers resulting from primary particles with energies above
10^{18} eV should be straightforward to detect with radar ranging techniques,
where the radar echoes are produced by scattering from the column of ionized
air produced by the shower. The idea has remained curiously untested since it
was proposed, but if our analysis is correct, such techniques could provide a
significant alternative approach to air shower detection in a standalone array
with high duty cycle, and might provide highly complementary measurements of
air showers detected in existing and planned ground arrays such as the Fly's
Eye or the Auger Project. The method should be particularly sensitive to
showers that are transverse to and relatively distant from the detector, and is
thus effective in characterizing penetrating horizontal showers such as those
that might be induced by ultra-high energy neutrino primaries.

categories: hep-ex astro-ph physics.ins-det physics.space-ph


title: Epsilon-prime / epsilon Results from KTeV

abstract:
  The first measurement of epsilon-prime / epsilon from the KTeV experiment at
Fermilab is described.


title: High Rate Neutrino Detectors for Neutrino Factories

abstract:
  Three types of high rate neutrino detectors for neutrino interaction physics
at neutrino factories are discussed. High performance general-purpose detectors
might collect event samples on the order of a billion events or more. This
could greatly improve on existing analyses of neutrino interactions and also
lead to new and important analysis topics including, for example, precise
determinations of the CKM matrix elements |Vub| and |Vcb|. The potential of
such general purpose detectors is illustrated with reference to a detector,
presented previously in reference hep-ex/9907033, that is structured around a
novel and compact vertexing and tracking neutrino target comprising a stack of
CCD pixel devices. Design ideas and prospects are also discussed for two types
of specialized detectors: (i) polarized targets filled with polarized solid
protium-deuterium (HD), for unique and powerful studies of the nucleon's spin
structure, and (ii) Fully active liquid tracking targets with masses of several
tonnes for precise determinations of the weak mixing angle, from the total
cross-section for neutrino-electron scattering. All three detector types pose
severe technical challenges but their utilization could add significantly to
the physics motivation for neutrino factories.


title: Low energy atmospheric muon neutrinos in MACRO

abstract:
  We present the measurement of two event samples induced by atmospheric
$\nu_\mu$ of average energy $ \bar {E}_\nu \sim 4 GeV$. In the first sample,
the neutrino interacts inside the MACRO detector producing an upward-going muon
leaving the apparatus. The ratio of the number of observed to expected events
is $ 0.57 \pm0.05_{stat} \pm0.06_{syst} \pm0.14_{theor}$ with an angular
distribution similar to that expected from the Bartol atmospheric neutrino
flux. The second is a mixed sample of internally produced downward-going muons
and externally produced upward-going muons stopping inside the detector. These
two subsamples are selected by topological criteria; the lack of timing
information makes it impossible to distinguish stopping from downgoing muons.
The ratio of the number of observed to expected events is $0.71 \pm 0.05_{stat}
\pm0.07_{syst} \pm0.18_{theor}$ . Using the ratio of the two subsamples (for
which most theoretical uncertainties cancel) we can test the pathlength
dependence of the oscillation hypothesis. The probability of agreement with the
no-oscillation hypothesis is 5% .
  The deviations of our observations from the expectations has a preferred
interpretation in terms of $\nu_\mu$ oscillations with maximal mixing and
$\Delta m^2 \sim 10^{-3} \div 10^{-2} eV^2$. These parameters are in agreement
with our results from upward throughgoing muons, induced by $\nu_\mu$ of much
higher energies.


title:
Bose-Einstein correlations in charged kaon pairs from Z0 decays into two
  hadronic jets

abstract:
  Bose-Einstein correlations in pairs of charged kaons produced in a sample of
3.9 million hadronic Z0 decays have been measured with the OPAL experiment at
LEP. Charged kaons were identified in the central tracking detector using their
specific energy loss in the drift chamber gas. The correlation function was
studied in two-jet events using a double ratio, formed by the number of
like-sign pairs normalised by a reference sample in the data, divided by the
same ratio in a Monte Carlo simulation. The enhancement at small values of the
four-momentum difference of the pair was parametrised using a Gaussian
function. The parameters of the Bose-Einstein correlations were measured to be
lambda = 0.82+-0.22(+0.17,-0.12) for the strength and R0 =
0.56+-0.08(+0.08,-0.06) fm for the kaon source radius, where the first errors
are statistical and the second systematic. Corrections for final-state
interactions are discussed.


title: The H1 Forward Proton Spectrometer at HERA

abstract:
  The forward proton spectrometer is part of the H1 detector at the HERA
collider. Protons with energies above 500 GeV and polar angles below 1 mrad can
be detected by this spectrometer. The main detector components are
scintillating fiber detectors read out by position-sensitive photo-multipliers.
These detectors are housed in so-called Roman Pots which allow them to be moved
close to the circulating proton beam. Four Roman Pot stations are located at
distances between 60 m and 90 m from the interaction point.


title:
Performance of the NuTeV Fe-Scintillator Sampling Calorimeter and
  Implications for Thin Calorimeters

abstract:
  NuTeV is a neutrino-nucleon deep inelastic scattering experiment at Fermilab.
The NuTeV detector is a traditional heavy target neutrino detector which
consists of an iron/liquid scintillator sampling calorimeter followed by a muon
spectrometer. The calorimeter response to hadrons, muons and electrons has been
measured in an in situ calibration beam over the energy range from 4.5 to 190
GeV. The small non-linearity of the response to hadrons is compared to the
expectation from the measured ratio of responses between electrons and hadrons
combined with the energy dependence of the fractional electromagnetic energy
deposition in the form of neutral pions in hadronic showers
$f_{\pi^{0}}(E_{\pi})$. The predictions use $f_{\pi^{0}}(E_{\pi})$ from the
Monte Carlo simulations by GHEISHA, GFLUKA and GCALOR and also from the
parameterizations of Wigmans and Groom. In addition, a study based on the NuTeV
hadron calibration data of the effectiveness of a thin calorimeter is
presented. The results of this study have important consequences for the energy
resolution of calorimeters used in other applications; for example, measuring
the cosmic ray flux in space or with balloon-based experiments.


title: Decay phi->pi+pi-

abstract:
  The process e+e- ->pi+pi- has been studied with the SND detector at VEPP-2M
e+e- collider in the vicinity of phi(1020) resonance. From the analysis of the
energy dependence of measured cross section the branching ratio
B(phi->pi+pi-)=(7.1+-1.1+-0.9)*10^{-5} and the phase psi_pi=-(34+-4+-3)degrees
of interference with the non-resonant pi+pi- production amplitude were
obtained.


title: Status of Experiments and Recent Results from CMD-2 Detector at Vepp-2M

abstract:
  The Cryogenic Magnetic Detector (CMD-2) is shortly described. Preliminary
results for the cross sections of $e^+$ $e^-$ annihilation into hadrons and
leptons are presented in the c.m. energy range from 0.37 to 1.39 GeV. The total
integrated luminosity of about 26 ${pb}^{-1}$ has been collected. The new
results for the $\rho$ and $\omega$ meson parameters are reported. The major
decay modes of the $\phi$ meson as well as its rare decays have been observed.


title:
a_1\pi Contribution to e^+e^-\to 4\pi Annihilation and \tau\to
  4\pi\nu_{\tau} Decay

abstract:
  The results of the study of the process e^+e^- \to 4\pi by the CMD-2
collaboration at VEPP-2M are presented. Analysis of the differential
distributions demonstrates the dominance of the a_1\pi and \omega\pi
intermediate states. Simple model, based on the assumption of a_1(1260)\pi and
\omega\pi dominance as intermediate states, successfully describes also the
data of CLEOII and ALEPH obtained recently for the decay \tau\to
4\pi\nu_{\tau}.


title:
Partial-wave analysis of the eta pi+ pi- system produced in the reaction
  pi-p --> eta pi+ pi- n at 18 GeV/c

abstract:
  A partial-wave analysis of 9082 eta pi+ pi- n events produced in the reaction
pi- p --> eta pi+ pi- n at 18.3 GeV/c has been carried out using data from
experiment 852 at Brookhaven National Laboratory. The data are dominated by
J^{PC} = 0^{-+} partial waves consistent with observation of the eta(1295) and
the eta(1440). The mass and width of the eta(1295) were determined to be 1282
+- 5 MeV and 66 +- 13 Mev respectively while the eta(1440) was observed with a
mass of 1404 +- 6 MeV and width of 80 +- 21 MeV. Other partial waves of
importance include the 1++ and the 1+- waves. Results of the partial wave
analysis are combined with results of other experiments to estimate f1(1285)
branching fractions. These values are considerably different from current
values determined without the aid of amplitude analyses.


title: ICANOE - Imaging and Calorimetric Neutrino Oscillation Experiment

abstract:
  The main scientific goal of the ICANOE detector is the one of elucidating in
a comprehensive way the pattern of neutrino masses and mixings, following the
SuperKamiokande results and the observed solar neutrinos deficit. To achieve
these goals, the experimental method is based upon the complementary and
simultaneous detection of CERN beam (CNGS) and cosmic ray (CR) events. For the
currently allowed values of the SuperKamiokande results, both CNGS and cosmic
ray data will give independent measurements and provide a precise determination
of the oscillation parameters.


title:
A Prototype RICH Detector Using Multi-Anode Photo Multiplier Tubes and
  Hybrid Photo-Diodes

abstract:
  The performance of a prototype Ring Imaging Cherenkov Detector is studied
using a charged particle beam. The detector performance, using CF4 and air as
radiators, is described. Cherenkov angle precision and photoelectron yield
using hybrid photo-diodes and multi-anode PMTs agree with simulations and are
assessed in terms of the requirements of the LHCb experiment.


title: Leading Particle Production in Light Flavour Jets

abstract:
  The energy distribution and type of the particle with the highest momentum in
quark jets are determined for each of the five quark flavours making only
minimal model assumptions. The analysis is based on a large statistics sample
of hadronic Z0 decays collected with the OPAL detector at the LEP e+e-
collider. These results provide a basis for future studies of light flavour
production at other centre-of-mass energies. We use our results to study the
hadronisation mechanism in light flavour jets and compare the data to the QCD
models JETSET and HERWIG. Within the JETSET model we also directly determine
the suppression of strange quarks to be gamma_s=0.422+-0.049 (stat.)+-0.059
(syst.) by comparing the production of charged and neutral kaons in strange and
non-strange light quark events. Finally we study the features of baryon
production.


title:
QCD Analyses and determinations of alpha-s in e+e- Annihilation at
  energies between 35 and 189 GeV

abstract:
  We employ data taken by the JADE and OPAL experiments for an integrated QCD
study in hadronic e+e- annihilations at c.m.s. energies ranging from 35 GeV
through 189 GeV. The study is based on jet-multiplicity related observables.
The observables are obtained to high jet resolution scales with the JADE,
Durham, Cambridge and cone jet finders, and compared with the predictions of
various QCD and Monte Carlo models. The strong coupling strength, alpha_s, is
determined at each energy by fits of O(alpha_s^2) calculations, as well as
matched O(alpha_s^2) and NLLA predictions, to the data. Matching schemes are
compared, and the dependence of the results on the choice of the
renormalization scale is investigated. The combination of the results using
matched predictions gives alpha_s(MZ)=0.1187+{0.0034}-{0.0019}. The strong
coupling is also obtained, at lower precision, from O(alpha_s^2) fits of the
c.m.s. energy evolution of some of the observables. A qualitative comparison is
made between the data and a recent MLLA prediction for mean jet multiplicities.


title: Search for Unstable Heavy and Excited Leptons at LEP2

abstract:
  Searches for unstable neutral and charged heavy leptons, N and L+-, and for
excited states of neutral and charged leptons, nu*, e*, mu*, and tau*, have
been performed in e+e- collisions using data collected by the OPAL detector at
LEP. The data analysed correspond to an integrated luminosity of about 58pb-1
at a centre-of-mass energy of 183GeV, and about 10pb-1 each at 161GeV and
172GeV. No evidence for new particles was found. Lower limits on the masses of
unstable heavy and excited leptons are derived. From the analysis of
charged-current, neutral-current, and photonic decays of singly produced
excited leptons, upper limits are determined for the ratio of the coupling to
the compositeness scale, f/Lambda, for masses up to the kinematic limit. For
excited leptons, the limits are established independently of the relative
values of the coupling constants f and f'.


title: Test Result of Time-Of-Propagation Cherenkov Counter

abstract:
  A new concept concerning Cherenkov detector for particle identification by
means of measuring both the Time-of-Propagation (TOP) and horizontal emission
angle ($\Phi$) of Cherenkov photons is described here. Some R&D works are also
reported.


title: Atmospheric Neutrinos

abstract:
  The results of experiments on atmospheric neutrinos are summarized, with the
important exception of Superkamiokande. The main emphasis is given to the
Soudan-2 and MACRO experiments. Both experiments observe atmospheric neutrino
anomalies in agreement with nu_mu-->> nu_tau oscillations with maximum mixing.
The nu_mu-->> nu_sterile oscillation is disfavored by the MACRO experiment.


title: Structure Functions in Deep Inelastic Lepton-Nucleon Scattering

abstract:
  Latest results on structure functions, as available at the Lepton-Photon
Symposium 1999, are presented. This report focusses on three experimental
areas: new structure function measurements, in particular from HERA at low x
and high Q2; results on light and heavy flavour densities; determinations of
the gluon distribution and of alpha_s. As the talk was delivered at a historic
moment and place, a few remarks were added recalling the exciting past and
looking into the promising future of deep inelastic scattering.


title: Search for D0-D0B Mixing

abstract:
  We report on a search for D0-D0B mixing made by studying the `wrong-sign'
process D0->K^+pi^-. The data come from an integrated luminosity of 9.0 1/fb of
e^+e^- collisions at s^(1/2) of approximately 10 GeV recorded with the CLEO
II.V detector. We measure the time integrated rate of the `wrong-sign' process
D0->K^+pi^- relative to that of the Cabibbo-favored process D0B->K^+pi^- to be
R=(0.332^{+0.063}_{-0.065}+-0.040)%. We study D0->K^+pi^- as a function of
decay time to distinguish direct doubly Cabibbo-suppressed decay from D0-D0B
mixing. The amplitudes that describe D0-D0B mixing, x' and y', are consistent
with zero. At the 95% C.L. and without assumptions concerning charge-parity
(CP) violating parameters, we find (1/2)x'^2 < 0.041% and -5.8% < y' < 1.0%.


title: New particle searches

abstract:
  This review presents recent results on new particle searches achieved at
Tevatron, Hera and LEP. After a brief outline of the searches on exotic
particles, results on supersymmetric particles and Higgs bosons are detailed.
Near future prospects are also given.


title: Forward Jets, Dijets, and Subjets at the Tevatron

abstract:
  Recent new results on the determination of the rapidity dependence of the
differential inclusive jet cross section, $<d^{2}\sigma/d\et d\eta >$, as a
function of jet $E_{T}$ in \ppbar collisions at $\sqrt{s}=1800$ GeV, measured
by the D0 detector at the Tevatron, are presented along with the comparisons to
theoretical next-to-leading order (NLO) perturbative QCD predictions. Triple
differential dijet cross sections, $<d^{3}\sigma/d\et d\eta_{1} d\eta_{2}>$, at
$\sqrt{s}=1800$ GeV, as well as the new results on jet structure at
$\sqrt{s}=1800$ and 630 GeV, as measured by the CDF and D0 detectors, are also
discussed.


title:
Inclusive Jet Cross Sections in $\bar{p}p$ Collisions at $\sqrt{s}$= 630
  and 1800 GeV

abstract:
  We have made a precise measurement of the inclusive jet cross section at
$\sqrt{s}$=1800 GeV. The result is based on an integrated luminosity of 92
pb^{-1} collected at the Fermilab Tevatron $\bar{p}p$ Collider with the D\O
detector. The measurement is reported as a function of jet transverse energy
(60 GeV <= E_{T} < 550 GeV), and in the pseudorapidity intervals |\eta| <= 0.5
and 0.1 <= |\eta| <= 0.7. A preliminary measurement of the pseudorapidity
dependence of inclusive jet production (|\eta| <= 1.5) is also discussed. The
results are in good agreement with predictions from next-to-leading order (NLO)
quantum chromodynamics (QCD). D\O has also determined the ratio of jet cross
sections at $\sqrt{s}$=630 GeV and $\sqrt{s}$=1800 GeV (|\eta| <= 0.5). This
preliminary measurement differs from NLO QCD predictions.


title: The DELPHI Silicon Tracker in the global pattern recognition

abstract:
  ALEPH and DELPHI were the first experiments operating a silicon vertex
detector at LEP. During the past 10 years of data taking the DELPHI Silicon
Tracker was upgraded three times to follow the different tracking requirements
for LEP 1 and LEP 2 as well as to improve the tracking performance. Several
steps in the development of the pattern recognition software were done in order
to understand and fully exploit the silicon tracker information. This article
gives an overview of the final algorithms and concepts of the track
reconstruction using the Silicon Tracker in DELPHI.


title: From Accelerators To Asteroids

abstract:
  In this talk I discuss the reach of traditional methods of elementary
particle physics in five broad experimental areas. For each of these areas I
inquire how that reach is, or might be, extended by experimental and
observational astrophysics and astronomy. The five areas are: searches for
particles with very large masses and measuring those masses, searches for
particles with very small masses and measuring those masses, searches for new
types of particles, searches for unexpected behavior of the known forces or for
new forces and searches for new phenomena at very high energies.


title: Observation of coasting beam at the HERA Proton--Ring

abstract:
  We present data collected with the HERA-B wire target which prove the
existence of coasting beam at the HERA proton storage ring. The coasting beam
is inherently produced by the proton machine operation and is not dominated by
target effects.


title:
Detection of very small neutrino masses in double-beta decay using laser
  tagging

abstract:
  We describe an approach to the study of neutrino masses that combines quantum
optics techniques with radiation detectors to obtain unprecedented sensitivity.
With it the search for Majorana neutrino masses down to $\sim$10 meV will
become accessible. The experimental technique uses the possibility of
individually detecting $\rm Ba^+$-ions in the final state of $\rm ^{136}Xe$
double-beta decay via resonant excitation with a set of lasers aimed at a
specific location in a large Time Projection Chamber. The specificity of the
atomic levels provides tagging and, together with more traditional event
recognition parameters, greatly suppresses radioactive backgrounds.


title: Three generation neutrino mixing is compatible with all experiments

abstract:
  We consider the minimal extension of the Standard Model with three
generations of massive neutrinos that mix. We then determine the parameters of
the model that satisfy all experimental constraints.


title: Status of the Muon (g-2) Experiment

abstract:
  The status of the muon (g-2) experiment, E821 at the Brookhaven AGS, is
given. A new result with a precision of 5 parts per million has been obtained
with direct muon injection into the ring and is presented. The theoretical
motivation for the experiment, and a discussion of the sensitivity to
non-standard model physics is also discussed.


title: A Measurement of the Mass and Full-Width of the $\eta_c$ Meson

abstract:
  In a sample of 7.8 million $J/\psi$ decays collected in the Beijing
Spectrometer, the process J/$\psi\to\gamma\eta_c$ is observed for five
different $\eta_c$ decay channels: $K^+K^-\pi^+\pi^-$, $\pi^+\pi^-\pi^+\pi^-$,
$K^\pm K^0_S \pi^\mp$ (with $K^0_S\to\pi^+\pi^-$), $\phi\phi$ (with $\phi\to
K^+K^-$) and $K^+K^-\pi^0$. From these signals, we determine the mass of
$\eta_c$ to be $2976.6\pm2.9\pm1.3$ MeV. Combining this result with a
previously reported result from a similar study using $\psi(2S)\to\gamma\eta_c$
detected in the same spectrometer gives $m_{\eta_c} = 2976.3\pm2.3\pm1.2$ MeV.
For the combined samples, we obtain $\Gamma_{\eta_c} = 11.0\pm 8.1\pm 4.1$ MeV.


title: Partial Wave Analysis of $J/\psi \to \gamma (K^{\pm}K_S^0\pi^{\mp})$

abstract:
  BES data on $J/\psi \to \gamma (K^{\pm} K_S^0 \pi^{\mp})$ are presented.
There is a strong peak due to $\eta(1440)/\iota$, which is fitted with a
Breit-Wigner amplitude with $s$-dependent widths for decays to $K^*K$, $\kappa
K$, $\eta \pi\pi$ and $\rho\rho$; $\kappa$ refers to the $K\pi$ S-wave. At a
$K\bar{K}\pi$ mass of $\sim 2040$ MeV, there is a second peak with width $\sim
400$ MeV; $J^P = 0^-$ is preferred over $1^+$ and $2^-$ respectively by 5.2 and
6.8 standard deviations. It is a possible candidate for a $0^-$ $s\bar sg$
hybrid partner of $\pi(1800)$.


title: Search for new Physics in rare B Decays

abstract:
  A search for the decay B+- to K+-K+-pi-+ was performed using data collected
by the OPAL detector at LEP. These decays are strongly suppressed in the
Standard Model but could occur with a higher branching ratio in supersymmetric
models, especially in those with R-parity violating couplings. No evidence for
a signal was observed and a 90% confidence level upper limit of 1.29x10^-4 was
set for the branching ratio.


title: Eperimental Results on Radiative Kaon Decays

abstract:
  This paper reviews the current status of experimental measurements of
radiative kaon decays. Several experiments at BNL, CERN and FNAL have recently
or will soon complete data collection; as a result, several new results are
available.


title:
The Q^2 Dependence of Dijet Cross Sections in gamma p Interactions at
  HERA

abstract:
  The dependence of the photon structure on the photon virtuality, Q^2, is
studied by measuring the reaction e^+p\to e^+ + {\rm jet} + {\rm jet} + {\rm X}
at photon-proton centre-of-mass energies 134 < W < 223 GeV. Events have been
selected in the Q^2 ranges \approx 0 GeV^2, 0.1-0.55 GeV^2, and 1.5-4.5 GeV^2,
having two jets with transverse energy E_T^{jet} > 5.5 GeV in the final state.
The dijet cross section has been measured as a function of the fractional
momentum of the photon participating in the hard process, x_gamma. The ratio of
the dijet cross section with x_gamma < 0.75 to that with x_gamma > 0.75
decreases as Q^2 increases. The data are compared with the predictions of NLO
pQCD and leading-order Monte Carlo programs using various parton distribution
functions of the photon. The measurements can be interpreted in terms of a
resolved photon component that falls with Q^2 but remains present at values of
Q^2 up to 4.5 GeV^2. However, none of the models considered gives a good
description of the data.


title: Rare Kaon Decays

abstract:
  The current status of rare kaon decay experiments is reviewed. New limits in
the search for Lepton Flavor Violation are discussed, as are new measurements
of the CKM matrix.


title: QCD studies with e+e- annihilation data at 172-189 GeV

abstract:
  We have studied hadronic events from e+e- annihilation data at centre-of-mass
energies of sqrt{s}=172, 183 and 189 GeV. The total integrated luminosity of
the three samples, measured with the OPAL detector, corresponds to 250 pb^-1.
  We present distributions of event shape variables, charged particle
multiplicity and momentum, measured separately in the three data samples. From
these we extract measurements of the strong coupling alpha_s, the mean charged
particle multiplicity <nch> and the peak position xi_0 in the xi_p=ln(1/x_p)
distribution.
  In general the data are described well by analytic QCD calculations and Monte
Carlo models. Our measured values of alpha_s, <nch> and xi_0 are consistent
with previous determinations at sqrt{s}=MZ.


title: Q-balls in Underground Experiments

abstract:
  In this paper we present some features of Q-balls and we discuss their
interactions with matter, and their energy losses in the Earth, for a large
range of velocities. These calculations are used to compute the fractional
geometrical acceptance of the MACRO detector. Furthermore a systematic analysis
of the energy losses of Q-balls in three types of detectors is investigated.
More specifically we have computed the light yield in liquid scintillators, the
ionization in streamer tubes and the Restricted Energy Loss in the CR39 nuclear
track detectors.


title: The Cleo III Upgrade

abstract:
  The CLEO detector at the Cornell Electron Storage Ring (CESR) is completing a
major upgrade that significantly extends its physics reach in the study of
heavy quarks and leptons. The major elements of this detector upgrade are the
installation of a ``fast'' ring imaging Cherenkov detector, a new central drift
chamber and a new barrel-style silicon strip vertex detector. Trigger and data
acquisition systems are also upgraded. We summarize the status of these
detector subsystems as well as the parallel CESR upgrade.


title: Further Search for the Decay K^+ --> pi^+ nu nubar

abstract:
  A search for additional evidence for the rare kaon decay K^+ --> pi^+ nu
nubar has been made with a new data set comparable in sensitivity to the
previous exposure that produced a single event.


title:
Measurement of Angular Distributions and R= sigma_L/sigma_T in
  Diffractive Electroproduction of rho^0 Mesons

abstract:
  Production and decay angular distributions were extracted from measurements
of exclusive electroproduction of the rho^0(770) meson over a range in the
virtual photon negative four-momentum squared 0.5< Q^2 <4 GeV^2 and the
photon-nucleon invariant mass range 3.8< W <6.5 GeV. The experiment was
performed with the HERMES spectrometer, using a longitudinally polarized
positron beam and a ^3He gas target internal to the HERA e^{+-} storage ring.
The event sample combines rho^0 mesons produced incoherently off individual
nucleons and coherently off the nucleus as a whole. The distributions in one
production angle and two angles describing the rho^0 -> pi+ pi- decay yielded
measurements of eight elements of the spin-density matrix, including one that
had not been measured before. The results are consistent with the dominance of
helicity-conserving amplitudes and natural parity exchange. The improved
precision achieved at 4< W <7 GeV, in combination with other data at W>7 GeV,
reveals evidence for an energy dependence in the ratio R of the longitudinal to
transverse cross sections at constant Q^2.


title:
Measurement of omega meson parameters in pi^+pi^-pi^0 decay mode with
  CMD-2

abstract:
  About 11 200 e^+e^- -> omega -> pi^+pi^-pi^0 events selected in the center of
mass energy range from 760 to 810 MeV were used for the measurement of the
\omega meson parameters. The following results have been obtained: sigma
_{0}=(1457 \pm 23 \pm 19)nb, m_{\omega}=(782.71 \pm 0.07 \pm 0.04) MeV/c^{2},
  \Gamma_{\omega}=(8.68 \pm 0.23 \pm 0.10) MeV,
  \Gamma_{e^+e^-}\cdot Br (\omega -> pi^+pi^-pi^0)=
  (0.528 \pm 0.012 \pm 0.007) \cdot 10^{-3} MeV.


title: Solar Neutrinos: What Next?

abstract:
  I summarize the current state of solar neutrino research and then give my
answer to the question: What should we do next?