title:
A realistic study of the nuclear transparency and the distorted momentum
  distributions in the semi-inclusive process 4He(e,e'p)X

abstract:
  The nuclear transparency and the distorted momentum distributions of 4He in
the semi-inclusive process 4He(e,e'p)X are calculated within the Glauber
multiple scattering approach using for the first time realistic four-body
variational wave functions embodying central and non-central nucleon-nucleon
(N-N) correlations. The contributions from N-N correlations and from Glauber
multiple scattering are taken into account exactly to all orders. It is shown
that non-central correlations significantly affect both the transparency and
the distorted momentum distributions; as a matter of fact: i) the small (approx
3%) value of the effect of correlations on the transparency results from an
appreciable cancellation between the short-range central repulsive correlations
and the intermediate-range attractive correlations, whose magnitude is
significantly affected by the non-central forces, and ii) the effect of Glauber
final state interactions on the momentum distribution is reduced by the
inclusion of tensor correlations.


title:
Transverse flow of nuclear matter in collisions of heavy nuclei at
  intermediate energies

abstract:
  The Quantum Molecular Dynamics Model (IQMD) is used to investigate the origin
of the collective transverse velocity observed in heavy ion experiments. We
find that there are three contributions to this effect: initial-final state
correlations, potential interactions and collisions. For a given nuclear
equation of state (eos) the increase of the transverse velocity with increasing
beam energy is caused by the potential part. For a given beam energy the
collective transverse velocity is independent of the nuclear eos but the
relative contributions of potential and collisions differ. In view of the
importance of the potential interactions between the nucleons it is not evident
that the similarity of the radial velocities measured for fragments at beam
energies below 1 AGeV and that for mesons at beam energies above 2 AGeV is more
than accidental.


title: Unversal Features of the Order-Parameter Fluctuations

abstract:
  We discuss the universal scaling laws of order parameter fluctuations in any
system in which the second-order critical behavior can be identified. These
scaling laws can be derived rigorously for equilibrium systems when combined
with the finite-size scaling analysis. The relation between order parameter,
criticality and scaling law of fluctuations has been established and the
connexion between the scaling function and the critical exponents has been
found.


title:
A linked cluster expansion for the calculation of the semi-inclusive
  A(e,e'p)X processes using correlated Glauber wave functions

abstract:
  The distorted one-body mixed density matrix, which is the basic nuclear
quantity appearing in the definition of the cross section for the
semi-inclusive A(e,e'p)X processes, is calculated within a linked-cluster
expansion based upon correlated wave functions and the Glauber multiple
scattering theory to take into account the final state interaction of the
ejected nucleon. The nuclear transparency for 16O and 40Ca is calculated using
realistic central and non-central correlations and the important role played by
the latter is illustrated.


title:
Microscopic Calculations of Weak Interaction Rates of Nuclei in Stellar
  Environment for A = 18 to 100

abstract:
  We report here the microscopic calculation of weak interaction rates in
stellar matter for 709 nuclei with A = 18 to 100 using a generalized form of
proton-neutron quasiparticle RPA model with separable Gamow-Teller forces. This
is the first ever extensive microscopic calculation of weak rates calculated
over a wide temperature-density grid which includes 10^7 \leq T(K) \leq 30
\times 10^9 and 10 \leq \rho Y_{e} (gcm^{-3}) \leq 10^{11}, and over a larger
mass range. Particle emission processes from excited states, previously
ignored, are taken into account, and are found to significantly affect some
$\beta$ decay rates. The calculated capture and decay rates take into
consideration the latest experimental energy levels and $ft$ value
compilations. Our calculation of electron capture and $\beta$-decay rates, in
the $fp$-shell, show considerable differences with a recently reported shell
model diagonalization approach calculation.


title: Dyson schwinger equations: Connecting small and large length-scales

abstract:
  I illustrate the phenomenological application of Dyson-Schwinger equations to
the calculation of meson properties observable at TJNAF. Particular emphasis is
given to this framework's ability to unify long-range effects constrained by
chiral symmetry with short-range effects prescribed by perturbation theory, and
interpolate between them.


title: Collapse and the Tritium Endpoint Pileup

abstract:
  The beta-decay of a tritium nucleus produces an entangled quantum system, a
beta electron, a helium nucleus, and an antineutrino. For finite collapse
times, the post-collapse beta electron energy can originate from a range of
pre-collapse energies due to the uncertainty principle. Long collapse times
give negligible uncertainty, so the pre-collapse spectrum must approach that of
isolated nuclei. We calculate the post-collapse electron spectrum which shows a
collapse-dependent pileup near the endpoint. Comparison with observation shows
that a collapse time of 1 x 10^-17 s explains the observed pileup. The collapse
of the entangled quantum system must be triggered by the environment: most
likely an atomic (molecular) electron initially bound to the atomic (molecular)
tritium source or perhaps ambient gas molecules. Coincidentally, the 40 eV
tritium atom-helium ion energy level shift is unobservably small for times
shorter than the system collapse time. We conclude that an atomic (molecular)
electron triggers the collapse once the 40 eV shift becomes detectible and the
electron detects the helium nucleus. Thus collapse may explain the tritium
endpoint pileup.


title: Period of the gamma-ray staggering in the 150Gd superdeformed region

abstract:
  It has been previously proposed to explain gamma-ray staggerings in the
deexcitation of some superdeformed bands in the $^{150}$Gd region in terms of a
coupling between global rotation and intrinsic vortical modes. The observed
4$\hbar$ period for the phenomenon is suggested from our microscopic Routhian
calculations using the Skyrme SkM* effective interaction.


title: Particle Interferometry for Relativistic Heavy-Ion Collisions

abstract:
  In this report we give a detailed account on Hanbury Brown/Twiss (HBT)
particle interferometric methods for relativistic heavy-ion collisions. These
exploit identical two-particle correlations to gain access to the space-time
geometry and dynamics of the final freeze-out stage. The connection between the
measured correlations in momentum space and the phase-space structure of the
particle emitter is established, both with and without final state
interactions. Suitable Gaussian parametrizations for the two-particle
correlation function are derived and the physical interpretation of their
parameters is explained. After reviewing various model studies, we show how a
combined analysis of single- and two-particle spectra allows to reconstruct the
final state of relativistic heavy-ion collisions.


title: Study of Omega, Eta, Eta-prime and D-minus mesic nuclei

abstract:
  Using the quark-meson coupling (QMC) model, we investigate whether $\omega,
\eta, \eta'$ and $D^-$ mesons form meson-nucleus bound states. Our results
suggest that one should expect to find $\eta$- and $\omega$-nucleus bound
states in all the nuclei considered. Furthermore, it is shown that the $D^-$
meson will form quite narrow bound states with $^{208}$Pb.


title:
Tests and applications of self-consistent cranking in the interacting
  boson model

abstract:
  The self-consistent cranking method is tested by comparing the cranking
calculations in the interacting boson model with the exact results obtained
from the SU(3) and O(6) dynamical symmetries and from numerical
diagonalization. The method is used to study the spin dependence of shape
variables in the $sd$ and $sdg$ boson models. When realistic sets of parameters
are used, both models lead to similar results: axial shape is retained with
increasing cranking frequency while fluctuations in the shape variable $\gamma$
are slightly reduced.


title:
The Landau-Migdal Parameters, g'_NN and g'_N\Delta and Pion
  Condensations

abstract:
  The Landau-Migdal parameters for nucleon-nucleon (g'_NN) and nucleon-\Delta
(g'_N\Delta) couplings are estimated from recent experimental data on the giant
Gamow-Teller state of 90Nb. The observed quenching of the GT strength by 10%
provides 0.16<g'_N\Delta<0.23 for g'_\Delta\Delta <1.0, while the excitation
energy g'_NN\sim 0.59. The critical density of pion condensations is much lower
than those previously discussed with the universality ansatz.


title:
Status and Future Prospects in Searches for New Interactions in Neutron
  and Nuclear Beta-decay, Muon- and Pion-decay

abstract:
  The interest, the status and the perspectives of various experiments in
neutron and nuclear beta-decay, muon-decay and pion-decays are discussed. The
talk is segmented into a discussion of the decay-rates and of the
energy-spectra and correlations. The impact on various scenarios of "new
physics" is briefly mentioned; left-right symmetric models are discussed in
more detail and the informations gained from the considered experiments is
compared to those from other sources.


title: Multifragmentation of non-spherical nuclei

abstract:
  The shape influence of decaying thermalized source on various characteristics
of multifragmentation as well as its interplay with effects of angular momentum
and collective expansion are first studied and the most pertinent variables are
proposed. The analysis is based on the extension of the statistical
microcanonical multifragmentation model.


title: Proton Single Particle Energy Shifts due to Coulomb Correlations

abstract:
  A theoretically consistent approach to the calculation of the Coulomb
correlation corrections to the single--particle energies is presented. New
contributions to the single--particle energies previously overlooked in the
literature are now identified and taken into account. We show that the
interplay between the Coulomb interaction and the strong interaction, which is
enhanced in the nuclear surface, leads to an upward shift of the proton
single--particle levels. This shift affects the position of the calculated
proton drip line, a shift towards decreasing $Z$. We describe briefly a similar
mechanism which is at work for neutron levels. The same mechanism is
responsible for significant corrections to the mass difference of the mirror
nuclei (Nolen--Schiffer anomaly) and to the effective proton mass.


title:
Recent progress on the chiral unitary approach to meson meson and meson
  baryon interactions

abstract:
  We report on recent progress on the chiral unitary approach, analogous to the
effective range expansion in Quantum Mechanics, which is shown to have a much
larger convergence radius than ordinary chiral perturbation theory, allowing
one to reproduce data for meson meson interaction up to 1.2 GeV. Applications
to physical processes so far unsuited for a standard chiral perturbative
approach are presented. Results for the extension of these ideas to the meson
baryon sector are discussed, together with applications to kaons in a nuclear
medium and $K^-$ atoms.


title: Chiral Transition in Nuclear Medium and Relevant Observables

abstract:
  We discuss how the possible changes of hadron properties can be tested,
associated with the chiral transition in nuclear medium; the hadrons discussed
are the vector mesons,the $\sigma$ meson and the chiral partner of the nucleon.
We emphasize that the proper quantity is the spectral function which describes
the nuclear medium having a hadron; the analysis of electro-quasielastic
reactions, for instance, has a relevance to the physics of CERES. The
similarity is indicated between the physics discussed here with that of giant
resonances. Experiments using nuclear targets are proposed to observe the
$\sigma$ meson and to explore how the partial chiral restoration in nuclear
medium manifests itself.


title: Causality in relativistic many body theory

abstract:
  The stability of the nuclear matter system with respect to density
fluctuations is examined exploring in detail the pole structure of the
electro-nuclear response functions. Making extensive use of the method of
dispersion integrals we calculate the full polarization propagator not only for
real energies in the spacelike and timelike regime but also in the whole
complex energy plane. The latter proved to be necessary in order to identify
unphysical causality violating poles which are the consequence of a neglection
of vacuum polarization. On the contrary it is shown that Dirac sea effects
stabilize the nuclear matter system shifting the unphysical pole from the upper
energy plane back to the real axis. The exchange of strength between these real
timelike collective excitations and the spacelike energy regime is shown to
lead to a reduction of the quasielastic peak as it is seen in electron
scattering experiments. Neglecting vacuum polarization one also obtains a
reduction of the quasielastic peak but in this case the strength is partly
shifted to the causality violating pole mentioned above which consequently
cannot be considered as a physical reliable result. Our investigation of the
response function in the energy region above the threshold of nucleon
anti-nucleon production leads to another remarkable result. Treating the
nucleons as point-like Dirac particles we show that for any isospin independent
NN-interaction RPA-correlations provide a reduction of the production amplitude
for $p\bar p$-pairs by a factor 2.


title: Thermodynamical characterization of heavy ion reactions

abstract:
  An detailed study of the thermodynamical state of nuclear matter in transport
calculations of heavy--ion reactions is presented. In particular we determine
temperatures from an analysis of the local momentum space distribution on one
hand, and from a fit to fragment energy spectra in terms of a blast model with
radial flow and temperature on the other. We apply this to spectator and
participant matter. In spectator we find regions of spinodal instability with
temperatures and densities which are consistent with experiments. In the
participant we find different temperatures for different fragment masses,
indicating that the fragments are not emitted from a source in thermal and
chemical equilibrium.


title: Halflife of 56Ni in cosmic rays

abstract:
  A measurement of the 56Ni cosmic ray abundance has been discussed as a
possible tool to determine the acceleration time scale of relativistic
particles in cosmic rays. This conjecture will depend on the halflife of
totally ionized 56Ni which can only decay by higher-order forbidden
transitions. We have calculated this halflife within large-scale shell model
calculations and find t_{1/2} \approx 4 \times 10^4 years, only slightly larger
than the currently available experimental lower limit, but too short for 56Ni
to serve as a cosmic ray chronometer.


title: Multifragmentation and the Renormalization Group

abstract:
  The possible usefulness of the renormalization group method in Nuclear
Physics is pointed out in this talk in the context of the nuclear
multifragmentation. The presentation is rather superficial and sketchy, to
indicate the main lines only. But I believe that the idea is warrant of
further, more careful studies.


title:
$g_{NK\Lambda}$ and $g_{NK\Sigma}$ from QCD Sum Rules in the $\gamma_5
  \sigma_{\mu \nu}$ structure

abstract:
  The NKY coupling constant for $Y = \Lambda$ and $\Sigma$ is evaluated in a
QCD sum rule calculation. We study the Borel sum rule for the three point
function of one pseudoscalar one nucleon and one hyperon current up to order
six in the operator product expansion. The Borel transform is performed with
respect to the nucleon and hyperon momenta, which are taken to be equal. We
discuss and extend the result of a previous analysis in the
$\rlap{/}{q}i\gamma_5$ structure and compare it with the result obtained with
the use of the $\gamma_5 \sigma_{\mu \nu}$ structure. We find that the effect
of pole-continuum transitions is very important in the $\rlap{/}{q}i\gamma_5$
structure and that it changes completely results obtained in previous analysis.


title: Simulation of Heavy Ion Reactions with Nonlocal Kinetic Equations

abstract:
  The incorporation of realistic trajectories of two-particle scattering into
existing BUU or QMD codes meets considerable difficulties. We propose a method
of replacing the scattering event by a tractable non-local scenario reproducing
the correct asymptotics. The first principle derivation justifies the use of
corresponding nonlocal kinetic equations. The nonlocal shifts are necessary if
the system should approach an equation of state with second quantum virial
coefficient. The modifications of QMD and BUU codes are discussed and
comparison are presented with resent data. We find a pre-equilibrium production
of particles leading to higher energetic distributions of protons.


title: A Schematic Model For Density-Dependent Vector Meson Masses

abstract:
  A schematic two-level model consisting of a "collective" bosonic state and an
"elementary" meson is constructed that provides interpolation from a hadronic
description (a la Rapp/Wambach) to B/R scaling for the description of
properties of vector mesons in dense medium. The development is based on a
close analogy to the degenerate schematic model of Brown for giant resonances
in nuclei.


title:
The Effects of Deformation on Isovector Electromagnetic and Weak
  Transition Strengths

abstract:
  The summed strength for transitions from the ground state of $^{12}C$ via the
operators $\vec{s}t, \vec{\ell}t, rY't, r[Y's]^{\lambda}t$ and
$r[Y'\ell]^{\lambda}t$ are calculated using the $\Delta N = 0$ rotational
model. If we choose the z component of the isospin operator $t_{z}$, the above
operators are relevant to electromagnetic transitions; if we choose $t_{+}$
they are relevant to weak transitions such as neutrino capture. In going from
the spherical limit to the asymptotic (oblate) limit the strength for the
operator $\vec{s} t$ decreases steadily to zero; the strength for the operator
$\vec{\ell}\tau$ (scissors mode) increases by a factor of three. For the last
three operators - isovector dipole, spin dipole and orbital dipole (including
the twist mode) it is shown that the summed strength is independant of
deformation. The main difference in the behavior is that for the first two
operators we have in-shell transitions whereas for the last three operators the
transitions are out of shell.


title: Shell correction energy for bubble nuclei

abstract:
  The positioning of a bubble inside a many fermion system does not affect the
volume, surface or curvature terms in the liquid drop expansion of the total
energy. Besides possible Coulomb effects, the only other contribution to the
ground state energy of such a system arises from shell effects. We show that
the potential energy surface is a rather shallow function of the displacement
of the bubble from the center and in most cases the preferential position of a
bubble is off center. Systems with bubbles are expected to have bands of
extremely low lying collective states, corresponding to various bubble
displacements.


title: Deuteron formation in nuclear matter within the Faddeev approach

abstract:
  We consider deuteron formation in heavy ion collisions at intermediate
energies. The elementary reaction rates (Nd -> NNN) in this context are
calculated using rigorous Faddeev methods. To this end an in-medium Faddeev
equation that consistently includes the energy shift and Pauli blocking effects
has been derived and solved numerically. As a first application we have
calculated the life-time of deuteron fluctuations for nuclear densities and
temperatures typical for the final stage of heavy ion collisions. We find
substantial differences between using the isolated and the in-medium rates.


title: Chiral corrections in hadron spectroscopy

abstract:
  We show that the implementation of chiral symmetry in recent studies of the
hadron spectrum in the context of the constituent quark model is inconsistent
with chiral perturbation theory. In particular, we show that the leading
nonanalytic (LNA) contributions to the hadron masses are incorrect in such
approaches. The failure to implement the correct chiral behaviour of QCD
results in incorrect systematics for the corrections to the masses.


title: Shell-Model Effective Operators for Muon Capture in ^{20}Ne

abstract:
  It has been proposed that the discrepancy between the partially-conserved
axial-current prediction and the nuclear shell-model calculations of the ratio
$C_P/C_A$ in the muon-capture reactions can be solved in the case of ^{28}Si by
introducing effective transition operators. Recently there has been
experimental interest in measuring the needed angular correlations also in
^{20}Ne. Inspired by this, we have performed a shell-model analysis employing
effective transition operators in the shell-model formalism for the transition
$^{20}Ne(0^+_{g.s.})+\mu^- \to ^{20}F(1^+; 1.057 MeV) + \nu_\mu$. Comparison of
the calculated capture rates with existing data supports the use of effective
transition operators. Based on our calculations, as soon as the experimental
anisotropy data becomes available, the limits for the ratio $C_P/ C_A$ can be
extracted.


title: Effective Field Theory of Nuclear Forces

abstract:
  The application of the effective field theory (EFT) method to nuclear systems
is reviewed. The roles of degrees of freedom, QCD symmetries, power counting,
renormalization, and potentials are discussed. EFTs are constructed for various
energy regimes of relevance in nuclear physics, and are used in systematic
expansions to derive nuclear forces in terms of a number of parameters that
embody information about QCD dynamics. Two-, three-, and many-nucleon systems,
including external probes, are considered.


title: Elliptic flow from a parton cascade

abstract:
  The dependence of elliptic flow at RHIC energies on the effective parton
scattering cross section is calculated using the ZPC parton cascade model. We
show that the v_2 measure of elliptic flow saturates early in the evolution
before the hadronization transition to a rather large value ~0.05-0.15 as
\sigma_g varies from 2-10 mb and thus is a sensitive probe of the dynamics in
the plasma phase.


title:
Study of effective interaction from single particle transfer reactions
  on f-p shell nuclei

abstract:
  The present study concentrates on the average effective two-body interaction
matrix elements being extracted, using sum-rule techniques, from transfer
reactions on target states having single orbital as well as two
orbitaloccupancy. This investigation deals with transfer reactions on f-p shell
nuclei involving (i) $1f_{7/2}$ and $2p_{3/2}$ transfer on target states using
$^{40}$Ca as inert core, and (ii) $2p_{3/2}$ and$1f_{5/2}$ transfer on states
using $^{56}$Ni as core.


title: Resonance propagation in heavy-ion scattering

abstract:
  The formalism developed by Jain and Kundu for the propagation of a resonance
in the nuclear medium has been modified to the case of heavy-ion collisions at
relativistic energies. The formalism includes coherently the contribution to
the observed di-lepton production from the decay of the resonance inside as
well as outside the nuclear medium. The calculated results are presented for
the $\rho $-meson production. It is observed that, in general, the shape,
magnitude and peak position of the coherently summed invariant mass
distribution is much different from that obtained by summing the inside and
outside contributions incoherently. Therefore, while inferring the modification
of hadron properties produced in heavy-ion collisions from experiments, it is
important that in theoretical calculations one includes the decay of the
propagating hadron from inside and outside the heavy-ion system coherently. We
also find that the mass distribution is sensitive to the amount of the medium
modification of the $\rho $-meson.


title: Superfluid nuclear matter calculations

abstract:
  We present a method to calculate nuclear matter properties in the superfluid
phase. The method is based on the use of self-consistent off-shell nucleon
propagators in the T-matrix equation. Such a complete treatment of the spectral
function, is required below and around $T_c$ due to a pseudogap formation in
the spectral function. In the superfluid phase we introduce the anomalous
self-energy in the fermion propagators and in the T-matrix equation,
consistently with the strong coupling BCS equations. The equations for the
nucleon spectral function include both a contribution of condensed and
scattering pairs. The method is illustrated by numerical calculations. Above
$T_c$ pseudogap formation is visible in the spectral function and below $T_c$ a
superfluid gap also appears.


title: Two-Particle Correlations in Relativistic Heavy-Ion Collisions

abstract:
  Two-particle momentum correlations between pairs of identical particles
produced in relativistic heavy-ion reactions can be analyzed to extract the
space-time structure of the collision fireball. We review recent progress in
the application of this method, based on newly developed theoretical tools and
new high-quality data from heavy-ion collision experiments. Implications for
our understanding of the collision dynamics and for the search for the
quark-gluon plasma are discussed.


title: Multi-step effects in subcoulomb breakup

abstract:
  Following earlier one-step calculations, we explore the contributions of
multi-step effects for the breakup of low energy $^8$B on $^{58}$Ni and
$^{208}$Pb within a coupled discretised continuum channels (CDCC) formalism.
The Coulomb multi-step differential cross section is significantly reduced for
all angles, the largest effect being the destructive interference of nuclear
couplings. The nuclear peak, at around $80^\circ$ in the one-step calculation
for $^{58}$Ni, virtually disappears.


title: Nucleosynhthesis in a Simmering Universe

abstract:
  Primordial nucleosynthesis is a success story of the standard big bang (SBB)
cosmology. We explore nucleosynthesis in possible models very different from
SBB in which the cosmological scale factor increases linearly with time right
through the period during which nucleosynthesis occurs till the present.It
turns out that weak interactions remain in thermal equilibrium upto
temperatures which are two orders of magnitude lower than the corresponding
(weak interaction decoupling) temperatures in SBB. Inverse beta decay of the
proton ensures adequate production of helium while producing primordial
metallicity much higher than that produced in SBB. Attractive features of such
models are the absence of the horizon, flatness and age problems and
consistency with classical cosmological tests.


title: Weak decays of medium and heavy Lambda-hypernuclei

abstract:
  We have made a new evaluation of the Lambda decay width in nuclear matter
within the Propagator Method. Through the Local Density Approximation it is
possible to obtain results in finite nuclei. We have also studied the
dependence of the widths on the N-N and Lambda-N short range correlations.
Using reasonable values for the parameters that control these correlations, as
well as realistic nuclear densities and Lambda wave functions, we reproduce,
for the first time, the experimental non-mesonic widths in a wide range of mass
numbers (from medium to heavy hypernuclei).


title:
Disoriented Chiral Condensates, Pion Probability Distributions and
  Parallels with Disordered System

abstract:
  A general expression is discussed for pion probability distributions coming
from relativistic heavy ion collisions. The general expression contains as
limits: 1) The disoriented chiral condensate (DCC), 2) the negative binomial
distribution and Pearson type III distribution, 3) a binomial or Gaussian
result, 4) and a Poisson distribution. This general expression approximates
other distributions such as a signal to noise laser distribution. Similarities
and differences of the DCC distribution with these other distribution are
studied. A connection with the theory of disordered systems will be discussed
which include spin-glasses, randomly broken objects, random and chaotic maps.


title:
Pre-critical Chiral Fluctuations in Nuclear Medium -- precursors of
  chiral restoration at $\rho_{B}\not=0 --

abstract:
  It is shown that an enhancement in the spectral function near 2$m_{\pi}$
threshold in the I=J=0 channel is a good signal of the partial restoration of
chiral symmetry in nuclear medium. Several experiments are discussed to detect
the enhancement, which uses hadron-nucleus and photo-nucleus reactions.


title: Effect of q-deformation in the NJL gap equation

abstract:
  We obtain a q-deformed algebra version of the Nambu-Jona-Lasinio model gap
equation. In this framework we discuss some hadronic properties such as the
dynamical mass generated for the quarks, the pion decay constant and the phase
transition present in this model.


title: Coulomb Effect: A Possible Probe for the Evolution of Hadronic Matter

abstract:
  Electromagnetic field produced in high-energy heavy-ion collisions contains
much useful information, because the field can be directly related to the
motion of the matter in the whole stage of the reaction. One can divide the
total electromagnetic field into three parts, i.e., the contributions from the
incident nuclei, non-participating nucleons and charged fluid, the latter
consisting of strongly interacting hadrons or quarks. Parametrizing the
space-time evolution of the charged fluid based on hydrodynamic model, we study
the development of the electromagnetic field which accompanies the high-energy
heavy-ion collisions. We found that the incident nuclei bring a rather strong
electromagnetic field to the interaction region of hadrons or quarks over a few
fm after the collision. On the other hand, the observed charged hadrons'
spectra are mostly affected (Coulomb effect) by the field of the charged fluid.
We compare the result of our model with experimental data and found that the
model reproduces them well. The pion yield ratio pi^-/pi+ at a RHIC energy,
Au+Au 100+100 GeV/nucleon, is also predicted.


title:
Analysis of resonance multipoles from polarization observables in eta
  photoproduction

abstract:
  A combined analysis of new eta photoproduction data for total and
differential cross sections, target asymmetry and photon asymmetry is
presented. Using a few reasonable assumptions we perform the first
model-independent analysis of the E0+, E2- and M2- eta photoproduction
multipoles. Making use of the well-known A3/2 helicity amplitude of the
D13(1520) state we extract its branching ratio to the eta-N channel,
Gamma(eta,N)/Gamma = (0.08 +- 0.01)%. At higher energies, we show that the
photon asymmetry is extremely sensitive to small multipoles that are excited by
photons in the helicity 3/2 state. The new GRAAL photon asymmetry data at
higher energy show a clear signal of the F15(1680) excitation which permits
extracting an F15(1680)->eta,N branching ratio of (0.15 +0.35 -0.10)%.


title:
Quasielastic Electron Scattering from Nuclei: Random-Phase vs. Ring
  Approximations

abstract:
  We investigate the extent to which the nuclear transverse response to
electron scattering in the quasielastic region, evaluated in the random-phase
approximation can be described by ring approximation calculations. Different
effective interactions based on a standard model of the type g'+V_pi+V_rho are
employed. For each momentum transfer, we have obtained the value of g'_0
permitting the ring response to match the position of the peak and/or the
non-energy weighted sum rule provided by the random-phase approach has been
obtained. It is found that, in general, it is not possible to reproduce both
magnitudes simultaneously for a given g'_0 value.


title:
Thomas-Ehrman shifts in nuclei around ^{16}O and role of residual
  nuclear interaction

abstract:
  The asymmetry in the energy spectra between mirror nuclei (the Thomas-Ehrman
shifts) around $^{16}$O is investigated from a phenomenological viewpoint. The
recent data on proton-rich nuclei indicates that the residual nuclear
interaction is reduced for the loosely bound s-orbit by as much as 30%, which
originates in the broad radial distribution of the proton single-particle wave
function.


title: QCD sum rules with two-point correlation function

abstract:
  We construct three different sum rules from the two-point correlation
function with pion, $i\int d^4x e^{iq\cdot x} <0| T J_N(x) {\bar
J}_N(0)|\pi(p)>$, beyond the soft-pion limit. The PS and PV coupling schemes in
the construction of the phenomenological side are carefully considered in each
sum rule. We discuss the dependence of the result on the specific Dirac
structure and identify the source of the dependence by making specific models
for higher resonances.


title: d\pi\pi decay of the d* dibaryon

abstract:
  The $d^* \to d \pi \pi$ partial decay width has been calculated in a
wave-function model for $d^*$ and $d$. It is found to be smaller than a
previous estimate by a factor of 7. A previously proposed dependence on
dibaryon sizes is confirmed. Additional dependence on the high-momentum
components of dibaryon wave functions is found.


title: Phases of dense matter in neutron stars

abstract:
  Recent equations of state for dense nuclear matter are discussed with
possible phase transitions arising in neutron stars such as pion, kaon and
hyperon kondensation, superfluidity and quark matter. Specifically, we treat
the nuclear to quark matter phase transition, the possible mixed phase and its
structure. A number of numerical calculations of rotating neutron stars with
and without phase transitions are given and compared to observed masses, radii,
temperatures and glitches.


title: Relativistic Treatment of Hypernuclear Decay

abstract:
  We compute for the first time the decay width of lambda-hypernuclei in a
relativistic mean-field approximation to the Walecka model. Due to the small
mass difference between the lambda-hyperon and its decay products---a nucleon
and a pion---the mesonic component of the decay is strongly Pauli blocked in
the nuclear medium. Thus, the in-medium decay becomes dominated by the
non-mesonic, or two-body, component of the decay. For this mode, the
lambda-hyperon decays into a nucleon and a spacelike nuclear excitation. In
this work we concentrate exclusively on the pion-like modes. By relying on the
analytic structure of the nucleon and pion propagators, we express the
non-mesonic component of the decay in terms of the spin-longitudinal response
function. This response has been constrained from precise quasielastic (p,n)
measurements done at LAMPF. We compute the spin-longitudinal response in a
relativistic random-phase-approximation model that reproduces accurately the
quasielastic data. By doing so, we obtain hypernuclear decay widths that are
considerably smaller---by factors of two or three---relative to existing
nonrelativistic calculations.


title: Analyzing power in nucleon-deuteron scattering and three-nucleon forces

abstract:
  Three-nucleon forces have been considered to be one possibility to resolve
the well known discrepancy between experimental values and theoretical
calculations of the nucleon analyzing power in low energy nucleon-deuteron
scattering. In this paper, we investigate possible effects of two-pion exchange
three-nucleon forces on the analyzing power and the differential cross section.
We found that the reason for different effects on the analyzing power by
different three-nucleon forces found in previous calculations is related to the
existence of the contact term. Effects of some variations of two-pion exchange
three-nucleon forces are investigated. Also, an expression for the measure of
the nucleon analyzing power with quartet P-wave phase shifts is presented.


title: Narrow deeply bound $K^-$ atomic states

abstract:
  Using optical potentials fitted to a comprehensive set of strong interaction
level shifts and widths in $K^-$ atoms, we predict that the $K^-$ atomic levels
which are inaccessible in the atomic cascade process are generally narrow,
spanning a range of widths about 50 - 1500 keV over the entire periodic table.
The mechanism for this narrowing is different from the mechanism for narrowing
of pionic atom levels. Examples of such `deeply bound' $K^-$ atomic states are
given, showing that in many cases these states should be reasonably well
resolved. Several reactions which could be used to form these `deeply bound'
states are mentioned. Narrow deeply bound states are expected also in $\bar{p}$
atoms.


title: The low-lying quadrupole collective excitations of Ru and Pd isotopes

abstract:
  Quadrupole excitations of even-even Ru and Pd isotopes are described within
microscopic approach based on the general collective Bohr model which includes
the effect of coupling with the pairing vibrations. The excitation energies and
E2 transition probabilities observed in 104-114Ru and 106-110Pd are reproduced
in the frame of the calculation containing no free parameters.


title:
Precritical pair fluctuations and formation of a pseudogap in
  low-density nuclear matter

abstract:
  Low-density nuclear matter at finite temperature is considered representing
the strong coupling situation of a highly correlated fermion system.
One-particle se lf-energies and the density of states in the vicinity of the
pairing transition point are presented. Within the Green function approach
model calculations are p erformed using the thermodynamic $T$ matrix in ladder
approximation. As a main r esult the formation of a pseudogap in the level
density near the critical temper ature of the pairing phase transition has been
found. It is shown that compared to mean field, the picture of the onset of the
pairing transition is essentially changed if correlations are taken into
account.


title: Extended Thomas-Fermi approximation to the one-body density matrix

abstract:
  The one-body density matrix is derived within the Extended Thomas-Fermi
approximation. This has been done starting from the Wigner-Kirkwood
distribution function for a non-local single-particle potential. The links
between this new approach to the density matrix with former ones available in
the literature are widely discussed. The semiclassical Hartree-Fock energy at
Extended Thomas-Fermi level is also obtained in the case of a non-local
one-body Hamiltonian. Numerical applications are performed using the Gogny and
Brink-Boeker effective interactions. The semiclassical binding energies and
root mean square radii are compared with the fully quantal ones and with those
obtained using the Strutinsky averaged method.


title: Nuclear moments for the neutrinoless double beta decay II

abstract:
  The recently developed formalism for the evaluation of nuclear form factors
in neutrinoless double beta decay is applied to $^{48}Ca$, $^{76}Ge$,
$^{82}Se$, $^{100}Mo$, $^{128}Te$ and $^{130}Te$ nuclei. Explicit analytical
expressions that follows from this theoretical development, in the single mode
model for the decay of $^{48}Ca$, have been worked out. They are useful both
for testing the full numerical calculations, and for analytically checking the
consistency with other formalisms. Large configuration space calculations are
compared with previous studies, where alternative formulations were used. Yet,
besides using the G-matrix as residual interaction, we here use a simple
$\delta$-force. Attention is paid to the connected effects of the short range
nuclear correlations and the finite nucleon size. Constraints on lepton number
violating terms in the weak Hamiltonian (effective neutrino Majorana mass and
effective right-handed current coupling strengths) are deduced.


title: Decay of Hypernuclei

abstract:
  We present a nonrelativistic transition potential for the weak
strangeness-changing reaction $\Lambda N \to NN$. The potential is based on a
one meson exchange model (OME), where, in addition to the long-ranged pion, the
exchange of the pseudoscalar $K, \eta$, as well as the vector $\rho, \omega,
K^*$ mesons is considered. Results obtained for different hypernuclear decay
observables are compared to the available experimental data.


title:
Charge independence breaking and charge symmetry breaking in the
  nucleon-nucleon interaction from effective field theory

abstract:
  We discuss charge symmetry and charge independence breaking in an effective
field theory approach for few-nucleon systems. We systematically introduce
strong isospin-violating and electromagnetic operators in the theory. The
charge dependence observed in the nucleon-nucleon scattering lengths is due to
one-pion exchange and one electromagnetic four-nucleon contact term. This gives
a parameter free expression for the charge dependence of the corresponding
effective ranges, which is in agreement with the rather small and uncertain
empirical determinations. We also compare the low energy phase shifts of the
$nn$ and the $np$ system.


title: Nuclear Phase Transitions in Transport Theory

abstract:
  Questions concerning nuclear phase transitions are addressed within the
transport theory. The issue of thermal equilibrium in the region of the
liquid-gas phase transition is investigated. Signatures of the transition to
the quark-gluon plasma are looked for.


title: True parameters of He-4-Sigma hypernucleus

abstract:
  It is shown that the true parameters of He-4-Sigma differ from the observed
ones. The reason is that the amplitude of He-4-Sigma production in the reaction
He-4(K-,pi-) sharply varies just in the corresponding mass region. It leads to
the small, but noticeable shift of the binding energy and the width. Besides,
the data at the threshold of Sigma-0 production is found to give an additional
evidence that He-4-Sigma width cannot exceed 8.0 - 8.5 MeV.


title:
Space-time versus particle-hole symmetry of collisions in a non-local
  kinetic equation for dense Fermi systems

abstract:
  Binary collisions in Fermi systems obey two fundamental symmetries
corresponding to the space and time inversion and to the interchange of
particles and holes. We show that beyond the local and instant approximation of
scattering-in and -out integrals of a kinetic equation, only one of symmetries
can be explicit while the other has to be covered by a constraint. This
constraint, derived from the optical theorem, allows one to convert at need an
explicit particle-hole symmetric form to the space-time symmetric form and vice
versa. We implement this constraint to heavy ion reactions, where simulation
algorithms require the space-time symmetry while former theories offer kinetic
equations with the explicit particle-hole symmetry.


title: The Reaction $pp\to p \Lambda K^+$ Near Threshold

abstract:
  We analyze the recent total cross section data for $pp \to p\Lambda K^+$ near
threshold measured at COSY. Using an effective range approximation for the
on-shell $p\Lambda$ S-wave final state interaction we extract from these data
the combination ${\cal K} = \sqrt{2|K_s|^2+|K_t|^2} = 0.38$ fm$^4$ of the
singlet ($K_s$) and triplet ($K_t$) threshold transition amplitudes. We present
an exploratory calculation of various (tree-level) vector and pseudoscalar
meson exchange diagrams. Pointlike $\omega$-exchange alone and the combined
($\rho^0,\omega,K^{*+} $)-exchange can explain the experimental value of $\cal
K$. The pseudoscalar meson exchanges based on a SU(3) chiral Lagrangian turn
out to be too large. However, when adding $\pi^0$-exchange in combination with
the resonant $\pi N \to S_{11}(1650)\to K \Lambda$ transition and introducing
monopole form factors with a cut-off $\Lambda_c= 1.5$ GeV one is again able to
reproduce the experimental value of $\cal K$. More exclusive measurements are
necessary to reveal the details of the $pp\to p\Lambda K^+$ production
mechanism.


title: Uncertainties in extracting $S_{17}$ from transfers

abstract:
  The transfer reaction $^7{\rm Be(d,n)}^8{\rm B}$ is modelled for the recent
low experimental energies using the DWBA. Tests of the validity of the ANC
method for the extraction of the $S_{17}$ astrophysical factor are performed.
  We show that a peripheral assumption is no longer accurate for center of mass
energies greater than approximately 15 MeV. In all cases we found that core
deformation and/or excitation effects to be small as long as the optical
potential for the entrance channel is not strongly surface peaked. Multistep
corrections to the DWBA were found to be small.
  We also emphasize that the lack of knowledge of the optical potentials for
the entrance and outgoing channels induces severe uncertainties in the
extracted $S_{17}$ astrophysical factor.


title:
A next-to-next-to-leading-order $pp \to pp\pi^0$ transition operator in
  chiral perturbation theory

abstract:
  We present a systematic analysis of next-to-next-to-leading-order diagrams
that contribute to the $pp \to pp\pi^0$ production at threshold. Analytic
expressions are given for the effective transition operators, and the relative
importance of various types of diagrams is discussed. The
vertex-correction-type graphs are found to give only small corrections to lower
order graphs in conformity with expectations. By contrast, we find very large
contributions from the two-pion graphs which can be interpreted as a part of
effective $\sigma$-meson exchange diagrams. The recoil correction to the pion
rescattering diagram also turns out to be large.


title:
Realistic Interactions and Configuration Mixing in Fermionic Molecular
  Dynamics

abstract:
  In Fermionic Molecular Dynamics the occurrence of multifragmentation depends
strongly on the intrinsic structure of the many-body state. Slater determinants
with narrow single-particle states and a cluster substructure show
multifragmentation in heavy-ion collisions while those with broad wave
functions, which resemble more a shell-model picture, deexcite by particle
emission. Which of the two type of states occurs as the ground state minimum or
as a local minimum in the energy depends on the effective interaction. Both may
equally well reproduce binding energy and radii of nuclei. This ambiguity led
us to reinvestigate the derivation of the effective interaction from realistic
nucleon-nucleon potentials by means of a unitary correlation operator which is
much more suited for dynamical calculations than the G-matrix or the Jastrow
method. First results of mixing many Slater determinants are also presented.


title: On the Simulation of Extended TDHF Theory

abstract:
  A novel method is presented for implementation of the extended mean-field
theory incorporating two-body collisions. At a given time, stochastic imaginary
time propagation of occupied states are used to generate a convenient basis.
The quantal collision terms, including memory effects, is then computed by a
backward mean-field propagation of these single-particle states. The method is
illustrated in an exactly solvable model. Whereas the usual TDHF fails to
reproduce the long time evolution, a good agreement is found between the
extended TDHF and the exact solution.


title:
Multifragmentation of non-spherical nuclei : Analysis of central Xe + Sn
  collisions at 50 MeV/nucl

abstract:
  The influence of shape of expanding and rotating source on various
characteristics of the multifragmentation process is studied. The analysis is
based on the extension of the statistical microcanonical multifragmentation
model. The comparison with the data is done for central Xe+Sn collisions at 50
A MeV as measured by INDRA Collaboration.


title: Renormalization of the one-pion-exchange interaction

abstract:
  A renormalization scheme for the nucleon-nucleon (NN) interaction based on a
subtracted T-matrix equation is proposed and applied to the one-pion-exchange
potential supplemented by contact interactions. The singlet and triplet
scattering lengths are given to fix the renormalized strengths of the contact
interactions. With only one scaling parameter ($\mu$), the results show an
overall very good agreement with neutron-proton data, particularly for the
observables related to the triplet channel. The agreement is qualitative in the
$^1S_0$ channel. Between the low-energy NN observables we have examined, the
mixing parameter of the $^3S_1-^3D_1$ states is the most sensible to the scale.
The scheme is renormalization group invariant for $\mu\to\infty$.


title: Deuteron electromagnetic form factors in the Light-Front Dynamics

abstract:
  The deuteron form factors are calculated in the framework of the relativistic
nucleon-meson dynamics, by means of the explicitly covariant light-front
approach. The inflluence of the nucleon electromagnetic form factors is
discussed.
  At $Q^2\leq 3$ (GeV/c)$^2$ the prediction for the structure function $A(Q^2)$
and for the tensor polarization observable $t_{20}$ are in agreement with the
recent data of CEBAF/TJNAF.


title: On the chiral low-density theorem

abstract:
  We show how the linear "low-density theorem" of Drukarev and Levin can be
extended to arbitrary positive integer power of the baryon density $\rho$. The
n^th coefficient in the McLaurin expansion of the fermion condensate's $\rho$
dependence is the connected n-nucleon sigma term matrix element. We calculate
the $O(\rho^2)$ coefficient in lowest-order perturbative approximation to the
linear sigma model and then show how this and other terms can be iterated to
arbitrarily high order. Convergence radius of the result is discussed.


title:
Analysis of reaction dynamics at RHIC in a combined parton/hadron
  transport approach

abstract:
  We introduce a transport approach which combines partonic and hadronic
degrees of freedom on an equal footing and discuss the resulting reaction
dynamics. The initial parton dynamics is modeled in the framework of the parton
cascade model, hadronization is performed via a cluster hadronization model and
configuration space coalescence, and the hadronic phase is described by a
microscopic hadronic transport approach. The resulting reaction dynamics
indicates a strong influence of hadronic rescattering on the space-time pattern
of hadronic freeze-out and on the shape of transverse mass spectra. Freeze-out
times and transverse radii increase by factors of 2 - 3 depending on the hadron
species.


title: Nucleon-Nucleon Effective Field Theory Without Pions

abstract:
  Nuclear processes involving momenta much below the mass of the pion may be
described by an effective field theory in which the pions do not appear as
explicit degrees of freedom. The effects of the pion and all other virtual
hadrons are reproduced by the coefficients of gauge-invariant local operators
involving the nucleon field. Nucleon-nucleon scattering phase shift data
constrains many of the coefficients that appear in the effective Lagrangean but
at some order in the expansion coefficients enter that must be constrained by
other observables. We compute several observables in the two-nucleon sector up
to next-to-next-to leading order in the effective field theory without pions,
or to the order at which a counterterm involving four-nucleon field operators
is encountered. Effective range theory is recovered from the effective field
theory up to the order where relativistic corrections enter or where
four-nucleon-external current local operators arise. For the deuteron magnetic
moment, quadrupole moment and the $np\to d\gamma$ radiative capture cross
section a four-nucleon-one-photon counterterm exists at next-to-leading order.
The electric polarizability and electric charge form factor of the deuteron are
determined up to next-to-next-to-leading order, which includes the first
appearance of relativistic corrections.


title: On the Backbending Mechanism of $^{48}$Cr

abstract:
  The mechanism of backbending in $^{48}$Cr is investigated in terms of the
Projected Shell Model and the Generator Coordinate Method. It is shown that
both methods are reasonable shell model truncation schemes. These two quite
different quantum mechanical approaches lead to a similar conclusion that the
backbending is due to a band crossing involving an excited band which is built
on simultaneously broken neutron and proton pairs in the ``intruder'' subshell
$f_{7/2}$. It is pointed out that this type of band crossing is usually known
to cause the second backbending in rare-earth nuclei.


title: Potential energy surfaces of superheavy nuclei

abstract:
  We investigate the structure of the potential energy surfaces of the
superheavy nuclei 258Fm, 264Hs, (Z=112,N=166), (Z=114,N=184), and (Z=120,N=172)
within the framework of self-consistent nuclear models, i.e. the
Skyrme-Hartree-Fock approach and the relativistic mean-field model. We compare
results obtained with one representative parametrisation of each model which is
successful in describing superheavy nuclei. We find systematic changes as
compared to the potential energy surfaces of heavy nuclei in the uranium
region: there is no sufficiently stable fission isomer any more, the importance
of triaxial configurations to lower the first barrier fades away, and
asymmetric fission paths compete down to rather small deformation. Comparing
the two models, it turns out that the relativistic mean-field model gives
generally smaller fission barriers.


title:
Beta decay of r-process waiting-point nuclei in a self-consistent
  approach

abstract:
  Beta-decay rates for spherical neutron-rich r-process waiting-point nuclei
are calculated within a fully self-consistent Quasiparticle Random-Phase
Approximation, formulated in the Hartree-Fock-Bogolyubov canonical
single-particle basis. The same Skyrme force is used everywhere in the
calculation except in the proton-neutron particle-particle channel, where a
finite-range force is consistently employed. In all but the heaviest nuclei,
the resulting half-lives are usually shorter by factors of 2 to 5 than those of
calculations that ignore the proton-neutron particle-particle interaction. The
shorter half-lives alter predictions for the abundance distribution of
r-process elements and for the time it takes to synthesize them.


title:
$\rho$-mass Modification in $He^3$ - a Signal of Restoration of Chiral
  Symmetry or Test for Nuclear Matter Models ?

abstract:
  Two recent experiments have demonstrated that the effective $\rho$-mass in
nuclear medium, as extracted from the $^3He(\gamma, \pi^+ \pi^-)$ reaction, is
substantially reduced. This has been advocated as an indication of partial
restoration of chiral symmetry in nuclear matter. We show that even in the
absence of chiral symmetry, effective mean field nuclear matter models can
explain these findings quantitatively.


title: Heavy-Ion Collisions and Black Holes in Anti-de-Sitter Space

abstract:
  Recent developments linking non-perturbative quantum gauge theories in
Minkowski space to classical gravity theories in anti-de-Sitter space are
reviewed at a simple level. It is suggested how these spectacular advances may
be extended to discuss the quark-gluon phase transition in terms of black holes
in anti-de-Sitter space, with possible relevance to heavy-ion collisions.


title:
Hadronic freeze-out following a first order hadronization phase
  transition in ultrarelativistic heavy-ion collisions

abstract:
  We analyze the hadronic freeze-out in ultra-relativistic heavy ion collisions
at RHIC in a transport approach which combines hydrodynamics for the early,
dense, deconfined stage of the reaction with a microscopic non-equilibrium
model for the later hadronic stage at which the hydrodynamic equilibrium
assumptions are not valid. With this ansatz we are able to self-consistently
calculate the freeze-out of the system and determine space-time hypersurfaces
for individual hadron species. The space-time domains of the freeze-out for
several hadron species are found to be actually four-dimensional, and differ
drastically for the individual hadrons species. Freeze-out radii distributions
are similar in width for most hadron species, even though the Omega-baryon is
found to be emitted rather close to the phase boundary and shows the smallest
freeze-out radii and times among all baryon species. The total lifetime of the
system does not change by more than 10% when going from SPS to RHIC energies.


title: Event by Event fluctuations and Inclusive Distribution

abstract:
  Event-by-event observables are compared with conventional inclusive
measurements. We find that moments of event-by-event fluctuations are closely
related to inclusive correlation functions. Implications for upcomming heavy
ion experiments are discussed.


title: Proton-Proton Fusion in Leading Order of Effective Field Theory

abstract:
  Using a recently developed effective field theory for the interactions of
nucleons at non-relativistic energies, we calculate the rate for the fusion
process $p + p \ra d + e^+ + \nu_e$ to leading order in the momentum expansion.
Coulomb effects are included non-perturbatively in a systematic way. The
resulting rate is independent of specific models for the strong interactions at
short distances and is in agreement with the standard result in the zero-range
approximation.


title: Beyond the Parton Cascade Model: Klaus Kinder-Geiger and VNI

abstract:
  I review Klaus Kinder-Geiger's contributions to the physics of relativistic
heavy ion collisions, in particular, the Parton Cascade Model. Klaus developed
this model in order to provide a QCD-based description of nucleus-nucleus
reactions at high energies such as they will soon become available at the
Brookhaven Relativistic Heavy Ion Collider. The PCM describes the collision
dynamics within the early and dense phase of the reaction in terms of the
relativistic, probabilistic transport of perturbative excitations (partons) of
the QCD vacuum. I will present an overview of the current state of the
numerical implementations of this model, as well as its predictions for nuclear
collisions at RHIC and LHC.


title: Nucleon Resonance Effects in $pp\to pp\pi^0$ near Threshold

abstract:
  The role of the low lying nucleon resonances beyond the $\Delta(1232)$ in the
reaction $pp\to pp\pi^0$ near threshold is shown to be numerically significant
by a calculation, which takes into account the pion re-scattering contribution
described by chiral perturbation theory and the short-range mechanisms that are
implied by the nucleon-nucleon interaction model. The intermediate N(1440)
(P$_{11}$) resonance is excited by the short-range exchange mechanisms, while
the N(1535) ($S_{11}$) and N(1520) ($D_{13}$) resonances are excited by $\eta$
and $\rho$ meson exchange, respectively. The $P_{11}$ increases the calculated
cross section, whereas the $S_{11}$ and $D_{13}$ resonances decrease it. The
calculation takes full account of the initial and final state interactions.


title: Calculation of exciton densities in SMMC

abstract:
  We develop a shell-model Monte Carlo (SMMC) method to calculate densities of
states with varying exciton (particle-hole) number. We then apply this method
to the doubly closed-shell nucleus 40Ca in a full 0s-1d-0f-1p shell-model space
and compare our results to those found using approximate analytic expressions
for the partial densities. We find that the effective one-body level density is
reduced by approximately 22% when a residual two-body interaction is included
in the shell model calculation.


title: BB Intermeson Potentials in the Quark Model

abstract:
  In this paper we derive quark model results for scattering amplitudes and
equivalent low energy potentials for heavy meson pairs, in which each meson
contains a heavy quark. This "BB" system is an attractive theoretical
laboratory for the study of the nuclear force between color singlets; the
hadronic system is relatively simple, and there are lattice gauge theory (LGT)
results for V_BB(r) which may be compared to phenomenological models. We find
that the quark model potential (after lattice smearing) has qualitative
similarities to the LGT potential in the two B*B* channels in which direct
comparison is possible, although there is evidence of a difference in length
scales. The quark model prediction of equal magnitude but opposite sign for I=0
and I=1 potentials also appears similar to LGT results at intermediate r. There
may however be a discrepancy between the LGT and quark model I=1 BB potentials.
A numerical study of the two-meson Schrodinger equations in the (bqbar)(bqbar)
and (cqbar)(cqbar) sectors with the quark model potentials finds a single
"molecule", in the I=0 BB* sector. Binding in other channels might occur if the
quark model forces are augmented by pion exchange.


title: Symmetry background of the stability of the second 0^+ state of 4^He

abstract:
  It was found in this paper that the dominant component of the wave function
of the second 0^+ state of 4^He and the corresponding component of the 3^H+p
channel have different spatial permutation symmetries. This fact will hinder
the wave function to extend from the interior region to the outgoing channel
and will lead to a narrower width.


title:
Non-extensive statistics, fluctuations and correlations in high energy
  nuclear collisions

abstract:
  Starting from the experimental evidence that high-energy nucleus-nucleus
collisions cannot be described in terms of superpositions of elementary
nucleon-nucleon interactions, we analyze the possibility that memory effects
and long-range forces imply a nonextensive statistical regime during high
energy heavy ion collisions. The relevance of these statistical effects and
their compatibility with the available experimental data are discussed. In
particular we show that theoretical estimates, obtained in the framework of the
generalized nonextensive thermostatistics, can reproduce the shape of the pion
transverse mass spectrum and explain the different physical origin of the
transverse momentum correlation function of the pions emitted during the
central Pb+Pb and during the p+p collisions at 158 A GeV.


title:
Radiative production of the Lambda(1405) resonance in K collisions on
  protons and nuclei

abstract:
  We have carried a theoretical study of the K^- p\to M B \gamma reaction with
M B = K^-p, \bar{K}^0 n, \pi^- \Sigma^+, \pi^+ \Sigma^-, \pi^0 \Sigma^0, \pi^0
\Lambda, for K^- lab. momenta between 200 and 500 MeV/c, using a chiral unitary
approach for the strong K^-p interaction with its coupled channels. The
\Lambda(1405) resonance, which is generated dynamically in this approach, shows
up clearly in the d\sigma/dM_I spectrum, providing new tests for chiral
symmetry and the unitary approach, as well as information regarding the nature
of the resonance. The photon detection alone, summing all channels, is shown to
reproduce quite accurately the strength and shape of the \Lambda(1405)
resonance. Analogous reactions in nuclei can provide much information on the
properties of this resonance in a nuclear medium.


title:
Mean field description of electron induced quasi-elastic excitation in
  nuclei

abstract:
  The validity of the approximations done in the mean field description of the
quasi-elastic excitation of medium-heavy nuclei is discussed. A test of the
reliability of the plane wave Born approximation is presented. The uncertainty
related to the choice of the electromagnetic nucleon form factors is discussed.
The effects produced by the meson exchange currents generated by the exchange
of a single pion are studied, as well as the need of including relativistic
corrections to the one-body currents. The results of the continuum shell model
and those of the Fermi gas model are compared and the need of treating the
emitted nucleon within a relativistic framework is studied. We analyze the
results of Random Phase Approximation calculations not only in terms of their
effects on the mean field responses, but also in terms of the theoretical
consistency in the choice of the effective residual interaction. The role of
the final state interaction is investigated. A microscopic justification of the
use of complex optical potential to describe the final state interaction is
provided. The effects of the final state interaction on the mean field
responses are studied with a sum rule conserving model. A comparison with the
experimental data measured in the C12 and Ca40 nuclei is shown.


title: Integral representation of the RPA correlation energy

abstract:
  Using the spectral function F'(z)/F(z) the RPA correlation energy and other
properties of a finite system can be written as a contour integral in a compact
way. This yields a transparent expression and reduces drastically the numerical
efforts for obtaining reliable values. The method applied to pairing vibrations
in rotating nuclei as an illustrative example.


title: Three-body properties in hot and dense nuclear matter

abstract:
  We derive three-body equations valid at finite densities and temperatures.
These are based on the cluster mean field approach consistently including
proper self energy corrections and the Pauli blocking. As an application we
investigate the binding energies of triton and determine the Mott densities and
momenta relevant for a many particle description of nuclear matter in a
generalized Beth-Uhlenbeck approach. The method, however is not restricted to
nuclear physics problems but may also be relevant, e.g., to treat
three-particle correlations in weekly doped semiconducters or strongly coupled
dense plasmas.


title: Electron scattering on two-neutron halo nuclei: The case of $^6$He

abstract:
  The formalism to describe electron scattering reactions on two-neutron halo
nuclei is developed. The halo nucleus is described as a three-body system
(core+n+n), and the wave function is obtained by solving the Faddeev equations
in coordinate space. We discuss elastic and quasielastic scattering using the
impulse approximation to describe the reaction mechanism. We apply the method
to investigate the case of electron scattering on $^6$He. Spectral functions,
response functions, and differential cross sections are calculated for both
neutron knockout and $\alpha$ knockout by the electron.


title: Resonances, Gamow Vectors and Time Asymmetric Quantum Theory

abstract:
  Decaying states can be represented by Gamow vectors with an exponential,
asymmetric time evolution. This asymmetric evolution is a manifestation of
irreversibility on the microphysical level. The Rigged Hilbert Space provides a
mathematical theory.


title:
NNLO Calculation of Two-Nucleon Scattering in EFT for a Two Yukawa Toy
  Model

abstract:
  The effective field theory (EFT) for a toy model of nucleons interacting via
a short range and a long range Yukawa potential is presented. The scattering
amplitude in the 1S0 channel is calculated up to NNLO using KSW power counting
scheme. A particular expansion of the amplitude about the pole at low
(imaginary) momentum is used to derive matching conditions for the EFT
couplings. In addition, after imposing constraints from a Renormalization Group
analysis, there are no new free parameters in the amplitude at NNLO. Comparing
the NNLO phase shifts to the full model we show that the EFT expansion is
converging.


title: Alpha Chain Structures of ^{12}C

abstract:
  N-\alpha structures of light nuclei with axial symmetry are studied using
relativistic Hartree approximation. Metastable excited states are searched in a
configuration space which allows linear alpha chain structures. As a result, it
is shown that ^{12}C has ^8Be + \alpha resonance state at about 1 MeV above
^8Be-\alpha threshold as an asymmetric 3-\alpha linear-chain structure, which
plays an important role in stellar nucleosynthesis.


title:
Coherent Photoproduction of Dileptons on Light Nuclei - a New Means to
  Learn about Vector Mesons

abstract:
  In the last years much work has been done to learn about the properties of
the $\rho$-meson in nuclear matter. In a calculation of the in-medium
spectralfunction of the $\rho$ we find that it is strongly modified by baryonic
resonances, especially the $D_{13}(1520)$, through its coupling to
resonance-hole states. In order to test the predictions of a model for the
in-medium properties of the $\rho$-meson so far mostly heavy-ion collision have
been used. We argue that the coherent photoproduction of $\rho$-mesons yields
additional information about the nature of the medium modification. It can be
shown that the production amplitude is sensitive on the momentum dependence of
the $\rho$-selfenergy. This can be used to distinguish experimentally between
various models for the $\rho$ in matter.


title: Renormalization Group Flow and Equation of State of Quarks and Mesons

abstract:
  Nonperturbative flow equations within an effective linear sigma model coupled
to constituent quarks for two quark flavors are derived and solved. A heat
kernel regularization is employed for a renormalization group improved
effective potential. We determine the initial values of the coupling constants
in the effective potential at zero temperature. Solving the evolution equations
with the same initial values at finite temperature in the chiral limit, we find
a second order phase transition at T_c \approx 150 MeV. Due to the smooth
decoupling of massive modes, we can directly link the low-temperature
four-dimensional theory to the three-dimensional high-temperature theory. We
calculate the equation of state in the chiral limit and for finite pion masses
and determine universal critical exponents.


title: Phase equivalent potentials for three-body halos

abstract:
  We compare the properties of three-body systems obtained with two-body
potentials with Pauli forbidden states and with the corresponding phase
equivalent two-body potentials. In the first case the forbidden states are
explicitly excluded in the calculation. Differences arise due to the off-shell
properties of these on-shell equivalent potentials. We use the adiabatic
hyperspherical method to formulate a practical prescription to exclude Pauli
forbidden states in three-body calculations. Schematic as well as realistic
potentials are used. Almost indistinguishable results are obtained.


title:
Hard Photons Beyond Proton-Neutron Bremsstrahlung in Heavy-Ion
  Collisions

abstract:
  We report on the study of extremely high energy photons, pions and etas,
produced in intermediate energy heavy-ion collisions. Possibility of imaging
the final-state phase space in these collisions by the Bose-Einstein
correlations for photons is critically examined.


title: Statistical Models of Nuclear Fragmentation

abstract:
  A method is presented that allows exact calculations of fragment multiplicity
distributions for a canonical ensemble of non-interacting clusters.
Fragmentation properties are shown to depend on only a few parameters.
Fragments are shown to be copiously produced above the transition temperature.
At this transition temperature, the calculated multiplicity distributions
broaden and become strongly super-Poissonian. This behavior is compared to
predictions from a percolation model. A corresponding microcanonical formalism
is also presented.


title: A soluble statistical model for nuclear fragmentation

abstract:
  The statistical model of Chase and Mekjian, which offers an analytic solution
for the canonical ensemble of non-interacting fragments, is investigated for
it's thermodynamic behavior. Various properties of the model, which exhibits a
first-order phase transition, are studied. The effects of finite particle
number are investigated. Three extensions of the model are considered, excluded
volume, Coulomb effects and inclusion of isospin degrees of freedom. A
formulation of a microcanonical version of the model is also presented.


title: Production of Dileptons in Heavy Ion Collisions at SPS-Energies

abstract:
  In this contribution we will discuss the production of low mass dileptons in
SPS-energy heavy ion collisions. We briefly review the current theoretical
situation before we turn to the analysis of the recent data for Pb+Au. We also
will discuss the role of baryons as a source for dileptons.


title: e^+e^- production from pp reactions at BEVALAC energies

abstract:
  We have performed a detailed study of dilepton production from pp collisions
including the subthreshold $\rho$ production via baryonic resonances (N(1520),
N(1700)) in addition to the conventional dilepton sources as $\pi^0, \eta,
\omega$ and $\Delta$ Dalitz decays and direct decays of vector mesons ($\rho,
\omega$). The role of baryonic resonances in $\rho$ production from
nucleon-nucleon collisions is studied in comparison to the DLS data which are
well described.


title: Chemical Equilibration in Pb+Pb Collisions at the SPS

abstract:
  An improved statistical model with excluded volume corrections and resonance
decays is introduced and applied to the complete presently available set of
particle ratios as measured by the various experiments at the SPS in Pb+Pb
collisions. The results imply that a high degree of hadrochemical equilibration
is reached at chemical freeze-out in Pb+Pb collisions.


title: Dispersion relations in quantum hadrodynamics with a finite cutoff

abstract:
  The dispersion relations in the real and imaginary parts of the meson
self-energies are studied to check the consistency of the "renormalization" in
cutoff field theory. It is shown that the dispersion relations are preserved by
the "renormalization"even if the finite cutoff and regulator are introduced in
the calculation by hand.


title: Saturating Cronin effect in ultrarelativistic proton-nucleus collisions

abstract:
  Pion and photon production cross sections are analyzed in proton-proton and
proton-nucleus collisions at energies 20 GeV < s^1/2 < 60 GeV. We separate the
proton-proton and nuclear contributions to transverse-momentum broadening and
suggest a new mechanism for the nuclear enhancement in the high
transverse-momentum region.


title:
Modern nucleon-nucleon interactions and charge-symmetry breaking in
  nuclei

abstract:
  Coulomb displacement energies, i.e., the differences between the energies of
corresponding nuclear states in mirror nuclei, are evaluated using recent
models for the nucleon-nucleon (NN) interaction. These modern NN potentials
account for breaking of isospin symmetry and reproduce $pp$ and $pn$ phase
shifts accurately. The predictions by these new potentials for the binding of
$^{16}O$ are calculated. A particular focus of our study are effects due to
nuclear correlations and charge-symmetry breaking (CSB). We find that the CSB
terms in the modern NN interactions substantially reduce the discrepancy
between theory and experiment for the Coulomb displacement energies; however,
our calculations do not completely explain the Nolen-Schiffer anomaly.
Potential sources for the remaining discrepancies are discussed.


title: Beyond collinearity in the N(e,e'q) process

abstract:
  We discuss a few examples of structure functions for polarized,
semi-inclusive scattering processes to show the richness of structure. Then we
indicate how polarization and particle production can be used to study the
quark and gluon structure of hadrons going further than the well-known parton
densities and fragmentation functions. We also emphasize how single spin
asymmetries in leptoproduction may shed light on explanations for single spin
asymmetries in pion production in pp collissions.


title: Instabilities of a hot expanded nuclear droplet

abstract:
  The stability of hot expanded nuclear droplets against small bulk and surface
oscillations is examined and possible consequences for multifragmentation are
discussed.


title: Bremsstrahlung Spectrum in alpha Decay

abstract:
  Using our previous approach to electromagnetic emission during tunneling, an
explicit, essentially classical, formula describing the bremsstrahlung spectrum
in alpha decay is derived. The role of tunneling motion in photon emission is
discussed. The shape of the spectrum is a universal function of the ratio Eg/Eo
, where Eg is the photon energy and Eo is a characteristic energy depending
only on the nuclear charge and the energy of the alpha particle.

categories: nucl-th nucl-ex physics.atom-ph quant-ph


title: Moments of event observable distributions and many-body correlations

abstract:
  We investigate event-by-event fluctuations for ensembles with non-fixed
multiplicity. Moments of event observable distributions, like total energy
distribution, total transverse momentum distribution, etc, are shown to be
related to the multi-body correlations present in the system. For classical
systems, these moments reduce in the absence of any correlations to the moments
of particle inclusive momentum distribution. As a consequence, a zero value for
the recently introduced $\Phi$-variable is shown to indicate the vanishing of
two-body correlations from one part, and of correlations between multiplicity
and momentum distributions from the other part. It is often misunderstood as a
measure of the degree of equilibration in the system.


title: Hadron production in Pb-Pb collisions at 158A GeV

abstract:
  A Fermi statistical model analysis of hadron abundances and spectra obtained
in several relativistic heavy ion collision experiments is utilized to
characterize a particle source. Properties consistent with a disintegrating,
hadron evaporating, deconfined quark-gluon plasma phase fireball are obtained,
with a baryochemical potential \mu_B=200-210MeV, and a temperature T_f\simeq
140-150MeV, significantly below previous expectations.


title:
Bremsstrahlung from Electrons and Positrons in Peripheral Relativistic
  Heavy Ion Collisions

abstract:
  We study the spectrum of the bremsstrahlung photons coming from the electrons
and positrons, which are produced in the strong electromagnetic fields present
in peripheral relativistic heavy ion collisions. We compare different
approaches, making use of the exact pair production cross section in heavy ion
collisions as well as the double equivalent photon approximation.


title:
Three-Body Scattering Below Breakup Threshold: An Approach without using
  Partial Waves

abstract:
  The Faddeev equation for three-body scattering below the three-body breakup
threshold is directly solved without employing a partial wave decomposition. In
the simplest form it is a three-dimensional integral equation in four
variables. From its solution the scattering amplitude is obtained as function
of vector Jacobi momenta. Based on Malfliet-Tjon type potentials differential
and total cross sections are calculated. The numerical stability of the
algorithm is demonstrated and the properties of the scattering amplitude
discussed.


title:
Can We Extract Lambda-Lambda Interaction from Two-Particle Momentum
  Correlation ?

abstract:
  We analyze the invariant mass spectrum of Lambda-Lambda in $^{12}C(K^-,K^+
Lambda Lambda)$ reaction at P(K^+)=1.65 GeV/c by using a combined framework of
IntraNuclear Cascade (INC) model and the correlation function technique. The
observed enhancement at low-invariant masses can be well reproduced with
attractive Lambda-Lambda interactions with the scattering length either in the
range a = -6 \sim -4 fm (no bound state) or a = 7 \sim 12 fm (with bound
state). We also discuss Lambda-Lambda correlation functions in central
relativistic heavy-ion collisions as a possible way to eliminate this discrete
ambiguity.


title:
Weak reactions on 12C within the Continuum Random Phase Approximation
  with partial occupancies

abstract:
  We extend our previous studies of the neutrino-induced reactions on 12C and
muon capture to include partial occupation of nuclear subshells in the
framework of the continuum random phase approximation. We find, in contrast to
the work by Auerbach et al., that a partial occupation of the p1/2 subshell
reduces the inclusive cross sections only slightly. The extended model
describes the muon capture rate and the 12C(nu_e,e-)12N cross section very
well. The recently updated flux and the improved model bring the calculated
12C(nu_mu,mu^-)12N cross section (~ 17.5 10^{-40} cm^2) and the data (12.4 +/-
0.3(stat.) +/- 1.8(syst.) 10^{-40} cm^2) closer together, but does not remove
the discrepancy fully.


title: Superfluidity in a Model of Massless Fermions Coupled to Scalar Bosons

abstract:
  We study superfluidity in a model of massless fermions coupled to a massive
scalar field through a Yukawa interaction. Gap equations for a condensate with
total spin J=0 are solved in the mean-field approximation. For the Yukawa
interaction, the gaps for right- and left-handed fermions are equal in
magnitude and opposite in sign, so that condensation occurs in the J^P = 0^+
channel. At finite scalar mass, there are two different gaps for fermions of a
given chirality, corresponding to condensation of particle pairs or of
antiparticle pairs. These gaps become degenerate in the limit of infinite
scalar mass.


title: Method of integral transforms for few-body reactions

abstract:
  The method of integral transforms is reviewed. In the framework of this
method reaction observables are obtained with the bound--state calculation
techniques. New developments are reported.


title: A basis of cranking operators for the pairing-plus-quadrupole model

abstract:
  We investigate the RPA normal-mode coordinates in the pairing-plus-quadrupole
model, with an eye on simplifying the application of large amplitude collective
motion techniques. At the Hartree-Bogoliubov minimum, the RPA modes are exactly
the cranking operators of the collective coordinate approach. We examine the
possibility of representing the self-consistent cranking operator by linear
combinations of a limited number of one-body operators. We study the Sm nuclei
as an example, and find that such representations exist in terms of operators
that are state-dependent in a characteristic manner.


title: e^+e^- Pair Production from $\gamma$ A Reactions

abstract:
  We present a calculation of e^+e^- production in $\gamma A$ reactions at MAMI
and TJNAF energies within a semi-classical BUU transport model. Dilepton
invariant mass spectra for $\gamma$C, $\gamma$Ca and $\gamma$Pb are calculated
at 0.8, 1.5 and 2.2 GeV. We focus on observable effects of medium modifications
of the $\rho$ and $\omega$ mesons. The in-medium widths of these mesons are
taken into account in a dynamical, consistent way. We discuss the transport
theoretical treatment of broad resonances.


title:
Systematic study of the effect of short range correlations on the form
  factors and densities of s-p and s-d shell nuclei

abstract:
  Analytical expressions of the one- and two-body terms in the cluster
expansion of the charge form factors and densities of the s-p and s-d shell
nuclei with N=Z are derived. They depend on the harmonic oscillator parameter b
and the parameter $\beta$ which originates from the Jastrow correlation
function. These expressions are used for the systematic study of the effect of
short range correlations on the form factors and densities and of the mass
dependence of the parameters b and $\beta$. These parameters have been
determined by fit to the experimental charge form factors. The inclusion of the
correlations reproduces the experimental charge form factors at the high
momentum transfers ($q\geq 2 1/fm$). It is found that while the parameter
$\beta$ is almost constant for the closed shell nuclei, $^4$He, $^{16}$O and
$^{40}$Ca, its values are larger (less correlated systems) for the open shell
nuclei, indicating a shell effect in the closed shell nuclei.


title: Three-pion exchange: a gap in the nucleon-nucleon potential

abstract:
  The leading contribution to the three-pion exchange nucleon-nucleon potential
is calculated in the framework of chiral symmetry. It has pseudoscalar and
axial components and is dominated by the former, which has a range of about 1.5
fm and tends to enhance the OPEP. The strength of this force does not depend on
the pion mass and hence it survives in the chiral limit.


title: Signatures of Disoriented Chiral Condensates from Charged Pions

abstract:
  We show that the variance in the number of charged pions (in a suitable range
of momentum space) provides a signature for the observation of a disoriented
chiral condensate (D$\chi$C). The signal should be observable even if multiple
domains of D$\chi$C form provided the average number of pions per domain is
significantly large than unity. The variance of the number charged pions alone
provides a signal which can be used even if the number of neutral pions cannot
be measured in a given detector. If the neutrals can be measured, however, the
fluctuations in the total number of pions provides a signature which
distinguishes disoriented chiral condensates from other hypothetical sources of
coherent states of pions.


title: Three-Body System with Short-Range Interactions

abstract:
  Within the framework of non-relativistic scalar effective field theory it is
shown that the problem of the cutoff dependence of the leading order amplitude
for a particle scattering off a two-body bound state can be solved without
introducing three-body forces.


title: Electromagnetic Modes in Deformed Nuclei

abstract:
  A strength function method is adopted to describe a coupling between electric
and magnetic modes of different multipolarity. The collective vibrations are
analysed for a separable residual interaction in the framework of the
random-phase approximation. The coupling between $M2$ and $E1$ giant resonances
is considered as an illustrative example.


title: Core-Polarization Contribution to the Nuclear Anapole Moment

abstract:
  The importance of core contributions to the anapole moment in nuclei is
examined. A model of the core-polarization correction is presented. The model
is based on the coupling of the valence particles to the spin-dipole $J=1^{-}$
giant resonances of the core. A shell-model calculation of this correction is
presented. The single-particle moments are calculated with Woods-Saxon and
Skyrme Hartree Fock radial wave functions, and the general issues associated
with nuclear configuration mixing are discussed.


title:
Isospin violation and meson-exchange models of the nucleon-nucleon
  interaction

abstract:
  Traditionally isospin violation (charge symmetry breaking and charge
dependence) has been modeled by the exchange of mesons between two nucleons.
Sources of isospin violation in these models include meson mass differences,
meson mixing (of pseudoscalar, vector, and axial-vector mesons) and isospin
violating couplings of mesons with nucleons. I will review the calculated
results of this theoretical approach and the NN data on isospin violation.


title: Particle Mixing and Charge Asymmetric $\Lambda N$ Forces

abstract:
  We calculate the contributions of a particular set of charge asymmetric
$\Lambda N$ interactions to the difference of the separation energies of
$^4_{\Lambda}$He and $^4_{\Lambda}$H. We use perturbation theory with four-body
variational Monte Carlo wave functions calculated from a Hamiltonian with two-
and three-hadron forces. We compare with the data and with an earlier
calculation made by one of us which employed a two-body wave function of the
$\Lambda$-nucleus type.


title: Interaction of Ultra-Cold Neutrons with Condensed Matter

abstract:
  General theory of neutron scattering (elastic and inelastic) is presented. It
is applicable for the whole domain of slow neutrons and includes as limiting
cases existing theories for thermal and cold neutrons and for elastic
scattering of UCN. New expression for inelastic scattering cross section for
UCN is proposed. It differs from the usually used by proper account of
re-scattering processes. Evidence for small heating and cooling of UCN is
given.


title: Model Calculations for the Two-Fragment Electro-Disintegration of $^4$He

abstract:
  Differential cross sections for the electro-disintegration process $e +
{^4He} \longrightarrow {^3H}+ p + e'$ are calculated, using a model in which
the final state interaction is included by means of a nucleon-nucleus (3+1)
potential constructed via Marchenko inversion. The required bound-state wave
functions are calculated within the integrodifferential equation approach
(IDEA). In our model the important condition that the initial bound state and
the final scattering state are orthogonal is fulfilled. The sensitivity of the
cross section to the input $p{^3H}$ interaction in certain kinematical regions
is investigated. The approach adopted could be useful in reactions involving
few cluster systems where effective interactions are not well known and exact
methods are presently unavailable. Although, our Plane-Wave Impulse
Approximation results exhibit, similarly to other calculations, a dip in the
five-fold differential cross-section around a missing momentum of $\sim 450
MeV/c$, it is argued that this is an artifact of the omission of re-scattering
four-nucleon processes.


title: Shape Coexistence and the Effective Nucleon-Nucleon Interaction

abstract:
  The phenomenon of shape coexistence is discussed within the self-consistent
Hartree-Fock method and the nuclear shell model. The occurrence of the
coexisting configurations with different intrinsic shapes is traced back to the
properties of the effective Hamiltonian.


title: Solar, Supernova, and Atmospheric Neutrinos

abstract:
  In these Canberra summer school lectures we treat a number of topical issues
in neutrino astrophysics: the solar neutrino problem, including the physics of
the standard solar model, helioseismology, and the possibility that the
solution involves new particle physics; atmospheric neutrinos; Dirac and
Majorana neutrino masses and their consequences for low-energy weak
interactions; red giant evolution as a test of new particle astrophysics; the
supernova mechanism; spin-flavor oscillations and oscillations into sterile
states, including the effects of density fluctuations; and neutrino-induced and
explosive nucleosynthesis.


title:
Neutron Star Vortex Dynamics and Magnetic Field Decay: Implications for
  High Density Nuclear Matter

abstract:
  We investigate the effect of the density-dependent proton and neutron gaps on
vortex dynamics in neutron stars. We argue that the persistence of neutron star
magnetic fields on timescales of $10^9$ y suggests a superconducting gap curve
with local maximum at intermediate density. We discuss the implications for
exotic core phenomena such as pion/kaon condensation or a transition to quark
matter.


title:
Comment on ``Determination of pion-baryon coupling constants from QCD
  sum rules''

abstract:
  In this comment, we propose possible errors in constructing the continuum
contribution in the sum rule studied by M. C. Birse and B. Krippa, Phys. Rev.
C. {\bf 54} (1996) 3240.


title:
Relativistic Hartree approach including both positive- and
  negative-energy bound states

abstract:
  We develop a relativistic model to describe the bound states of positive
energy and negative energy in finite nuclei at the same time. Instead of
searching for the negative-energy solution of the nucleon's Dirac equation, we
solve the Dirac equations for the nucleon and the anti-nucleon simultaneously.
The single-particle energies of negative-energy nucleons are obtained through
changing the sign of the single-particle energies of positive-energy
anti-nucleons. The contributions of the Dirac sea to the source terms of the
meson fields are evaluated by means of the derivative expansion up to the
leading derivative order for the one-meson loop and one-nucleon loop. After
refitting the parameters of the model to the properties of spherical nuclei,
the results of positive-energy sector are similar to that calculated within the
commonly used relativistic mean field theory under the no-sea approximation.
However, the bound levels of negative-energy nucleons vary drastically when the
vacuum contributions are taken into account. It implies that the
negative-energy spectra deserve a sensitive probe to the effective interactions
in addition to the positive-energy spectra.


title:
Shell model calculations of stellar weak interaction rates: I.
  Gamow-Teller distributions and spectra of nuclei in the mass range A=45-65

abstract:
  Electron capture and beta-decay rates on nuclei in the mass range A=45-65
play an important role in many astrophysical environments. The determination of
these rates by large-scale shell model calculations is desirable, but it
requires to reproduce the Gamow-Teller strength distributions and spectra of
the pf shell nuclei. We show in this paper that large-scale shell model
calculations, employing a slightly monopole-corrected version of the wellknown
KB3 interaction, fulfill these necessary requirements. In particular, our
calculations reproduce the experimentally available GT+ and GT- strength
distributions and the nuclear halflives, and describe the nuclear spectra
appropriately.


title: A Few Simple Observations on Pion-Condensation in Nuclei

abstract:
  We present a few simple observations on the occurrence of $\pi$-condensation
in Nuclei, aimed at clarifying the nature of the $\pi$-condensation implied by
the coherent nuclear $\pi$-N-$\Delta$ interaction, proposed in 1990 to explain
the puzzling emergence of the Shell-Model. We show that such condensation is
totally unrelated to the one proposed by A. B. Migdal at the beginning of '70,
which can easily be shown not to occur at the normal nucleon density
$\rho_{N}\simeq$ 0.17 fm${}^{-3}$.


title:
Is binary sequential decay compatible with the fragmentation of nuclei
  at high energy?

abstract:
  We use a binary sequential decay model in order to describe the fragmentation
of a nucleus induced by the high energy collisions of protons with Au nuclei.
Overall agreement between measured and calculated physical observables is
obtained. We evaluate and analyse the decay times obtained with two different
parametrisations of the decay rates and discuss the applicability of the model
to high energy fragmentation.


title: Kinetic freeze out

abstract:
  Freeze out of particles across a space-time hypersurface is discussed in
kinetic models. The calculation of final momentum distribution of emitted
particles is described for freeze out surfaces, with spacelike normals. The
resulting non-equilibrium distribution does not resemble, the previously
proposed, cut Juttner distribution, and shows non-exponential p_t-spectra
similar to the ones observed in experiments.


title: Isospin violation in the two-nucleon system

abstract:
  I discuss isospin violation in an effective field theory appraoch of the
nucleon-nucleon interaction. The observed leading order charge independence
breaking is explained in terms of one-pion exchange together with a
four-nucleon contact term. A general classification scheme of corrections to
this leading order results is presented and an explanation is offered why
charge-dependent pion-nucleon coupling constants can not play a role in the
observed isospin violation in the NN scattering lengths. Charge symmetry
breaking, the size of $\pi\gamma$-exchange graphs and the pionless theory are
also discussed.


title: Initial Conditions for Parton Cascades

abstract: I discuss the initial conditions for a parton cascade.


title:
The phase diagram and bulk thermodynamical quantities in the NJL model
  at finite temperature and density

abstract:
  We reexamine the recent instanton motivated studies of Alford, Rajagopal and
Wilczek, and Berges and Rajagopal in the framework of the standard SU(2)
Nambu-Jona-Lasinio model. The chiral phase diagram is calculated in the
temperature--density plane, and the pressure is evaluated as the function of
the density. Obtaining simple approximate relations describing the $T$-$\mu$
and $T$-$p_F$ phase transition lines we find that the results of the instanton
based model and that of the NJL model are identical. The diquark transition
line is also given.


title: Two-Step Contribution to Intermediate Energy (p,p') and (p,n) Reactions

abstract:
  We calculate the two-step contribution to (p,p') and (p,n) reactions at
intermediate energy. We describe the motion of the incident nucleon with plane
wave and compare the contribution from the two-step processes with that from
the one-step processes. To describe the two-step processes, we extende the
response functions into the nondiagonal ones with respect to the momentum
transfer q.
  We performed a numerical calculation for the cross sections of the $^{12}$C,
$^{40}$Ca(p,p') scatterings and the spin longitudinal and the spin transverse
cross sections of the $^{12}$C,$^{40}$Ca(p,n) reactions at 346 MeV and 494 MeV.
We found that the two-step contribution is appreciable in comparison with the
one-step processes in higher energy transfer region for the spin longitudinal
and the spin transverse (p,n) reactions. We also found that the two-step
processes give larger contribution to the spin transverse (p,n) reaction than
to the spin longitudinal reaction. This finding is very encouraging to
interpret the discrepancy between the DWIA calculation and the experimental
results of the spin longitudinal and the spin transverse cross sections.


title:
Real-Time Evolution of Soft Gluon Field Dynamics in Ultra-Relativistic
  Heavy-Ion Collisions

abstract:
  The dynamics of gluons and quarks in a relativistic nuclear collision are
described, within the framework of a classical mean-field transport theory, by
the coupled equations for the Yang-Mills field and a collection of colored
point particles. The particles are used to represent color source effects of
the valence quarks in the colliding nuclei. The possibilities of this approach
are studied to describe the real time evolution of small $x$ modes in the
classical effective theory in a non-perturbative coherent manner. The time
evolution of the color fields is explored in a numerical simulation of the
collision of two Lorentz-boosted clouds of color charged particles on a long
three-dimensional gauge lattice. We report results on soft gluon scattering and
coherent gluon radiation obtained in SU(2) gauge symmetry.


title: Relation of hard and total cross sections to centrality

abstract:
  We compare the fractions of the hard and geometric cross sections as a
function of impact parameter. For a given definition of central collisions, we
calculate the corresponding impact parameter and the fraction of the hard cross
section contained within this cut. We use charm quark production as a definite
example.