title: Di-neutron elastic transfer in the 4He(6He,6He)4He reaction

abstract:
  Elastic $^{6}$He+$^4$He data measured at $E_{\rm c.m.}=11.6,$ 15.9, and 60.3
MeV have been analyzed within the coupled reaction channels (CRC) formalism,
with the elastic-scattering and two-neutron ($2n$) transfer amplitudes
coherently included. Contributions from the direct (one-step) and sequential
(two-step) $2n$-transfers were treated explicitly based on a realistic
assumption for the $2n$-transfer form factor. The oscillatory pattern observed
in $^4$He($^6$He,$^6$He)$^4$He angular distribution at low energies was found
to be due to an interference between the elastic scattering and $2n$-transfer
amplitudes. Our CRC analysis shows consistently that the direct $2n$-transfer
strongly dominates over the sequential transfer and thus confirms the dominance
of 2$n-^4$He configuration over the $n-^5$He one in the $^6$He wave function.
This result suggests a strong clusterization of the two valence neutrons and
allows, therefore, a reliable estimate for the \emph{di-neutron} spectroscopic
amplitude.


title:
Statistical hadronization phenomenology in heavy ion collisions at SPS
  and RHIC energies

abstract:
  This dissertation examines the phenomenology of statistical hadronization at
ultrarelativistic energies. We start with an overview of current experimental
and theoretical issues in Relativistic heavy ion physics. We then introduce
statistical hadronization, and show how it gives a description of particle
abundances and spectra through covariance and entropy maximization. We argue
that a distinction can be made between equilibrated staged freeze-out in which
post-formation hadron interactions play an important role in determining
final-state observables, and non-equilibrium sudden freeze-out where spectra
and abundances get determined at the same time and further interactions are
negligible. We attempt to falsify sudden freeze-out by examining whether
particle abundances and spectra can be described using the same formation
temperature. This is done both in the equilibrium framework, and using a
chemical non-equilibrium ansatz. Our fits to experimental data suggest that the
sudden freeze-out model explains both the particle abundances and spectra. We
then try to extract the particle formation temperature, and quantify
post-freeze-out hadronic interactions using experimentally observable
resonances. We discuss observed resonances and suggest further measurements
that have the potential to distinguish between the possible freeze-out
scenarios experimentally. Finally, we infer from experimental data how particle
formation proceeds in spacetime, in particular whether freeze-out dynamics
agrees with the sudden freeze-out expectation. We examine particle spectra, and
show that they are not sensitive enough to pick the right freeze-out dynamics.
We suggest resonances and azimuthal anisotropy as experimental probes for this
task.


title:
Projected multicluster model with Jastrow and linear state dependent
  correlations for $12 \leq A \leq 16$ nuclei

abstract:
  Variational wave functions based on a Margenau-Brink cluster model with short
range and state dependent correlations, and angular momentum projection are
obtained for some nuclei with $12 \leq A \leq 16$. The calculations have been
carried out starting from the nucleon-nucleon interaction by using the
Variational Monte Carlo method. The configuration used consists of three alpha
clusters located at the apexes of an equilateral triangle, and an additional
cluster, not necessarily of alpha type, forming a tetrahedron. This cluster is
located at the top of its height. Short-range and state dependent correlations
are included by means of a central Jastrow factor and a linear operatorial
correlation factor respectively. Angular momentum projection is performed by
using the Peierls-Yoccoz operators. Optimal structures are obtained for all the
nuclei studied. Some aspects of our methodology have been tested by comparing
with previous calculations carried out without short range correlations. The
binding energy, the root mean square radius, and the one- and two-body
densities are reported. The effects of correlations on both the energy and the
nucleon distribution are analyzed systematically.


title:
Re-analysis of the nucleon space- and time-like electromagnetic form
  factors in a two-component model

abstract:
  Recent experimental data on space-like and time-like form factors of the
nucleon are analyzed in terms of a two-component model with a quark-like
intrinsic three-quark structure and quark-antiquark pairs.


title:
Energy Dependence of Jet Quenching and Life-time of the Dense Matter in
  High-energy Heavy-ion Collisions

abstract:
  Suppression of high $p_T$ hadron spectra in high-energy heavy-ion collisions
at different energies is studied within a pQCD parton model incorporating
medium induced parton energy loss. The $p_T$ dependence of the nuclear
modification factor $R_{AA}(p_T)$ is found to depend on both the energy
dependence of the parton energy loss and the power-law behavior of the initial
jet spectra. The high $p_T$ hadron suppression at $\sqrt{s}=62.4$ GeV and its
centrality dependence are studied in detail. The overall values of the
modification factor are found to provide strong constraints on the lifetime of
the dense matter.


title:
Spin structure of spin-1/2 baryon and spinless meson production
  amplitudes in photo and hadronic reactions

abstract:
  The most general spin structures of the spin-1/2 baryon and spinless meson
production operator for both photon and nucleon induced reactions are derived
from the partial-wave expansions of these reaction amplitudes. The present
method provides the coefficients multiplying each spin operator in terms of the
partial-wave matrix elements. The result should be useful in studies of these
reactions based on partial-wave analyses, especially, when spin observables are
considered.


title: New correlations induced by nuclear supersymmetry

abstract:
  We show that the nuclear supersymmetry model (n-susy) in its extended
version, predicts correlations in the nuclear structure matrix elements which
characterize transfer reactions between nuclei that belong to the same
supermultiplet. These correlations are related to the fermionic generators of
the superalgebra and if verified experimentally can provide a direct test of
the model.


title: Pairing transition of nuclei at finite temperature

abstract:
  Pairing transition at finite temperature was investigated by the shell model
and BCS calculations. The definitive signature of pairing transition is
identified by a "transition temperature" $T_t$ estimated from a "thermal"
odd-even mass difference, while there is no sharp phase transition because of
the finiteness of nucleus. It is found that $T_t$ is in good agreement with
predictions of critical temperature $T_c$ in the BCS approximation, and the
pairing correlations almost vanish at two points of the transition temperature
$T\approx 2T_{t}$. The BCS calculations show that the critical temperature
$T_c$ increases with increasing deformation.


title: Nuclear radius deduced from proton diffraction by a black nucleus

abstract:
  We find a new method to deduce nuclear radii from proton-nucleus elastic
scattering data. In this method a nucleus is viewed as a ``black'' sphere. A
diffraction pattern of protons by this sphere is equivalent to that of the
Fraunhofer diffraction by a circular hole of the same radius embedded in a
screen. We determine the black sphere radius in such a way as to reproduce the
empirical value of the angle of the observed first diffraction peak. It is
useful to identify this radius multiplied by $\sqrt{3/5}$ with the
root-mean-square matter radius of the target nucleus. For most of stable
isotopes of masses heavier than 50, it agrees, within the error bars, with the
values that were deduced in previous elaborate analyses from the data obtained
at proton incident energies higher than $\sim 800$ MeV.


title: Effective interactions and the nuclear shell-model

abstract:
  This review aims at a critical discussion of the interplay between effective
interactions derived from various many-body approaches and spectroscopic data
extracted from large scale shell-model studies. To achieve this, our many-body
scheme starts with the free nucleon-nucleon (NN) interaction, typically
modelled on various meson exchanges. The NN interaction is in turn renormalized
in order to derive an effective medium dependent interaction. The latter is in
turn used in shell-model calculations of selected nuclei. We also describe how
to sum up the parquet class of diagrams and present initial uses of the
effective interactions in coupled cluster many-body theory.


title: Calculation of Screening Masses in a Chiral Quark Model

abstract:
  We consider a simple model for the coordinate-space vacuum polarization
function which is often parametrized in terms of a screening mass. We discuss
the circumstances in which the standard result for the screening mass,
$m_{sc}=\pi T$, is obtained. In the model considered here, that result is
obtained when the momenta in the relevant vacuum polarization integral are
small with respect to the first Matsubara frequency.


title: Energy Systematics of Jet Tomography at RHIC: sqrt{s} = 62.4 vs 200 AGeV

abstract:
  The collision energy dependence of jet tomography is investigated within the
GLV formalism. The emphasis is on estimating systematic uncertainties resulting
from the interplay of energy loss fluctuations and the rapid increase of the
parton transverse momentum slopes as sqrt{s} decreases from 200 to 62 AGeV.


title: Seniority scenario for the 68-72Zn and 66-68Ni B(E2)^ difference

abstract:
  The very simple product of the number of particles by the number of holes
appearing in the expression of the reduced B(E2: 0+1 -> 2+1) (B(E2)^)
transition probability of even-even nuclei obtained from the extension of the
seniority scheme is used to analyze in a same time the experimental B(E2)^
values of 56-68 Ni and those of 62-72Zn. The evolution of these B(E2)^ values
with neutron number fits in with a scenario involving p-n interaction.


title:
Alpha-Particle Condensate in Nuclear Matter at Normal Density and
  Statistics of Composite Bosons

abstract:
  It is proved that alpha-particle states are well described by the Elliott
SU(3) model. This result is used to analyze the alpha-particle condensation
effect. It is shown that these states possess the basic attributes of the
alpha-condensate and, also, the normal nuclear density on frequent occasions.
The statistics of alpha-particles (and of arbitrary composite bosons) turns out
to be something other than the Bose-Einstein, Fermi-Dirac statistics, and
parastatistics.


title: Collective Path Connecting the Oblate and Prolate Local Minima in 68Se

abstract:
  By means of the adiabatic self-consistent collective coordinate method and
the pairing plus quadrupole interaction, we have obtained the selfconsistent
collective path connecting the oblate and prolate local minima in 68Se for the
first time. Along the collective path, the triaxial deformation parameter
(gamma) changes between 0 and 60 (degree) keeping the axially symmetric
deformation parameter (beta) approximately constant, indicating the importance
of triaxial deformation dynamics in the oblate-prolate shape coexistence
phenomena.


title: Hadronization via Coalescence

abstract:
  We review the quark coalescence model for hadronization in relativistic heavy
ion collisions and show how it can explain the observed large baryon to meson
ratio at intermediate transverse momentum and scaling of the elliptic flows of
identified hadrons. We also show its predictions on higher-order anisotropic
flows and discuss how quark coalescence applied to open- and hidden-charm
mesons can give insight to charm quark interactions in the quark-gluon plasma
and $J/\Psi$ production in heavy ion collisions.


title:
Continuum corrections to the level density and its dependence on
  excitation energy, n-p asymmetry, and deformation

abstract:
  In the independent-particle model, the nuclear level density is determined
from the neutron and proton single-particle level densities. The
single-particle level density for the positive-energy continuum levels is
important at high excitation energies for stable nuclei and at all excitation
energies for nuclei near the drip lines. This single-particle level density is
subdivided into compound-nucleus and gas components. Two methods were
considered for this subdivision. First in the subtraction method, the
single-particle level density is determined from the scattering phase shifts.
In the Gamov method, only the narrow Gamov states or resonances are included.
The level densities calculated with these two methods are similar, both can be
approximated by the backshifted Fermi-gas expression with level-density
parameters that are dependent on A, but with very little dependence on the
neutron or proton richness of the nucleus. However, a small decrease in the
level-density parameter was predicted for some nuclei very close to the drip
lines. The largest difference between the calculations using the two methods
was the deformation dependence on the level density. The Gamov method predicts
a very strong peaking of the level density at sphericity for high excitation
energies. This leads to a suppression of deformed configurations and,
consequently, the fission rate predicted by the statistical model is reduced in
the Gamov method.


title:
Uniqueness of Fisher plots and their inferred (nuclear) liquid-vapor
  phase diagrams

abstract:
  A detailed study of the lattice gas (Ising) model shows that the correct
definition of cluster concentration in the vapor at coexistence with the liquid
leads to Fisher plots that are unique, independent of fixed particle number
density $\rho_{\text{fixed}}$, and completely reliable for the characterization
of the liquid-vapor phase diagram of any van der Waals systems including
nuclear matter.


title: Hidden evidence of non-exponential nuclear decay

abstract:
  The framework to describe natural phenomena at their basics being quantum
mechanics, there exist a large number of common global phenomena occurring in
different branches of natural sciences. One such global phenomenon is
spontaneous quantum decay. However, its long time behaviour is experimentally
poorly known. Here we show, that by combining two genuine quantum mechanical
results, it is possible to infer on this large time behaviour, directly from
data. Specifically, we find evidence for non-exponential behaviour of alpha
decay of 8Be at large times from experiments.


title: The Vector Analyzing Power in Elastic Electron-Proton Scattering

abstract:
  We compute the vector analyzing power (VAP) for the elastic scattering of
transversely polarized electrons from protons at low energies using an
effective theory of electrons, protons, and photons. We study all contributions
through second order in $E/M$, where $E$ and $M$ are the electron energy and
nucleon mass, respectively. The leading order VAP arises from the imaginary
part of the interference of one- and two-photon exchange amplitudes.
Sub-leading contributions are generated by the nucleon magnetic moment and
charge radius as well as recoil corrections to the leading-order amplitude.
Working to ${\cal O}(E/M)^2$, we obtain a prediction for $A_n$ that is free of
unknown parameters and that agrees with the recent measurement of the VAP in
backward angle $ep$ scattering.


title: Boson Dominance in nuclei

abstract:
  We present a new method of bosonization of fermion systems applicable when
the partition function is dominated by composite bosons. Restricting the
partition function to such states we get an euclidean bosonic action from which
we derive the Hamiltonian. Such a procedure respects all the fermion
symmetries, in particular fermion number conservation, and provides a boson
mapping of all fermion operators.


title: Cronin effect from backward to forward rapidity

abstract:
  I discuss recent experimental data on the Cronin effect in deuteron-gold
collisions at the top RHIC energy, in a pseudorapidity range [-2,3]. Two
theoretical approaches are compared and contrasted: the pQCD-based
Glauber-Eikonal model and Colour Glass Condensate models. Neither can describe
the Cronin effect over the whole pseudorapidity interval up to now explored
experimentally, its most mysterious and intriguing part being at negative
rapidity.


title: Description of rotating $N=Z$ nuclei in terms of isovector pairing

abstract:
  A systematic investigation of the rotating $N=Z$ even-even nuclei in the mass
$A=58-80$ region has been performed within the frameworks of the Cranked
Relativistic Mean field, Cranked Relativistic Hartree Bogoliubov theories and
cranked Nilsson-Strutinsky approach. Most of the experimental data is well
accounted for in the calculations. The present study suggests that there is
strong isovector $np$-pair field at low spin, the strength of which is defined
by the isospin symmetry. At high spin, the isovector pair field is destroyed
and the data are well described by the calculations assuming zero pairing. No
clear evidence for the existence of the isoscalar $t=0$ $np$-pairing has been
obtained in the present investigation.


title: The two-nucleon system at next-to-next-to-next-to-leading order

abstract:
  We consider the two-nucleon system at next-to-next-to-next-to-leading order
(N^3LO) in chiral effective field theory. The two-nucleon potential at N^3LO
consists of one-, two- and three-pion exchanges and a set of contact
interactions with zero, two and four derivatives. In addition, one has to take
into account various isospin-breaking and relativistic corrections. We employ
spectral function regularization for the multi-pion exchanges. Within this
framework, it is shown that the three-pion exchange contribution is negligibly
small. The low-energy constants (LECs) related to pion-nucleon vertices are
taken consistently from studies of pion-nucleon scattering in chiral
perturbation theory. The total of 26 four-nucleon LECs has been determined by a
combined fit to some np and pp phase shifts from the Nijmegen analysis together
with the nn scattering length. The description of nucleon-nucleon scattering
and the deuteron observables at N^3LO is improved compared to the one at NLO
and NNLO. The theoretical uncertainties in observables are estimated based on
the variation of the cut-offs in the spectral function representation of the
potential and in the regulator utilized in the Lippmann-Schwinger equation.


title: Wobbling excitations and tilted rotation in 163-Lu

abstract:
  Using a microscopic self-consistent model, we analyse wobbling excitations
built upon the rotational band in $^{163}$Lu, which is identified with a
rotation of a triaxial, strongly deformed shape. We find that the presence of
pairing correlations substantially affects the energy of the wobbling
excitations. Our calculations predict an onset of a tilted rotation at a
critical rotational frequency where the energy of the wobbling excitations
approaches zero.


title: Gaussian expansion approach to Coulomb breakup

abstract:
  An accurate treatment of Coulomb breakup reactions is presented by using both
the Gaussian expansion method and the method of continuum discretized coupled
channels. As $L^2$-type basis functions for describing bound- and
continuum-states of a projectile, we take complex-range Gaussian functions,
which form in good approximation a complete set in a large configuration space
being important for Coulomb-breakup processes. Accuracy of the method is tested
quantitatively for $^{8}{\rm B}+^{58}$Ni scattering at 25.8 MeV.


title: Nuclear structure of 178Hf related to the spin-16, 31-year isomer

abstract:
  The projected shell model is used to study the multi-quasiparticle and
collective excitations of 178Hf. With an axially symmetric basis, the spin-16
isomer at 2.4 MeV appears to be well separated in energy/spin space from other
configurations. However, projected energy surface calculations suggest that
178Hf has significant softness to axially asymmetric shapes, which can strongly
modify the level distribution. The implications for photodeexitation of the
isomer are discussed.


title: Modelling Pentaquark and Heptaquark States

abstract:
  A schematic model for hadronic states, based on constituent quarks and
antiquarks and gluon pairs, is discussed. The phenomenological interaction
between quarks and gluons is QCD motivated. The obtained hadronic spectrum
leads to the identification of nucleon and $\Delta$ resonances and to
pentaquark and heptaquark states. The predicted lowest pentaquark state
($J^{\pi} = {1/2}^-$) lies at the energy of 1.5 GeV and it is associated to the
observed $\Theta^+(1540)$ state. For heptaquarks ($J^{\pi} = {1/2}^+, {3/2}^+$)
the model predicts the lowest state at 2.5 GeV.


title: A schematic model for QCD. III : Hadronic states

abstract:
  The hadronic spectrum obtained in the framework of a QCD-inspired schematic
model, is presented. The model is the extension of a previous version, whose
basic degrees of freedom are constituent quarks and antiquarks, and gluons. The
interaction between quarks and gluons is a phenomenological interaction and its
parameters are fixed from data. The classification of the states, in terms of
quark and antiquark and gluon configurations is based on symmetry
considerations, and it is independent of the chosen interaction. Following this
procedure, nucleon and $\Delta$ resonances are identified, as well as various
penta- and hepta-quarks states. The lowest pentaquarks state is predicted at
1.5 GeV and it has negative parity, while the lowest hepta-quarks state has
positive parity and its energy is of the order of 2.5 GeV.


title: Phase Structure of 2-Flavor Quark Matter: Heterogeneous Superconductors

abstract:
  We analyze the free energy of charge and color neutral 2-flavor quark matter
within the BCS approximation. We consider both the homogeneous gapless
superconducting phase and the heterogeneous mixed phase where normal and BCS
superconducting phases coexist. We calculate the surface tension between normal
and superconducting phases and use it to compare the free energies of the
gapless and mixed phases. Our calculation, which retains only the leading order
gradient contribution to the free energy, indicates that the mixed phase is
energetically favored over an interesting range of densities of relevance to 2
flavor quark matter in neutron stars.


title:
Neutrino scattering off pair-breaking and collective excitations in
  superfluid neutron matter and in color-flavor locked quark matter

abstract:
  We calculate the correlation functions needed to describe the linear response
of superfluid matter, and go on to calculate the differential cross section for
neutral-current neutrino scattering in superfluid neutron matter and in
color-flavor locked quark matter (CFL). We report the first calculation of
scattering rates that includes neutrino interactions with both pair-breaking
excitations and low-lying collective excitations (Goldstone modes). Our results
apply both above and below the critical temperature, allowing use in
simulations of neutrino transport in supernovae and neutron stars.


title:
Faddeev calculation of 6 He Lambda Lambda using SU_6 quark-model
  baryon-baryon interactions

abstract:
  Quark-model hyperon-nucleon and hyperon-hyperon interactions by the
Kyoto-Niigata group are applied to the two-Lambda plus alpha system in a new
three-cluster Faddeev formalism using two-cluster resonating-group method
kernels. The model fss2 gives a reasonable two-Lambda separation energy Delta
B_{Lambda Lambda}=1.41 MeV, which is consistent with the recent empirical
value, Delta B^{exp}_{Lambda Lambda}=1.01 +/- 0.20 MeV, deduced from the Nagara
event. Some important effects that are not taken into account in the present
calculation are discussed.


title:
Renormalization of NN-Scattering with One Pion Exchange and Boundary
  Conditions

abstract:
  A non perturbative renormalization scheme for Nucleon-Nucleon interaction
based on boundary conditions at short distances is presented and applied to the
One Pion Exchange Potential. It is free of off-shell ambiguities and
ultraviolet divergences, provides finite results at any step of the calculation
and allows to remove the short distance cut-off in a suitable way. Low energy
constants and their non-perturbative evolution can directly be obtained from
experimental threshold parameters in a completely unique and model independent
way when the long range explicit pion effects are eliminated. This allows to
compute scattering phase shifts which are, by construction consistent with the
effective range expansion to a given order in the C.M. momentum $p$. In the
singlet $^1S_0$ and triplet $^3S_1- ^3D_1$ channels ultraviolet fixed points
and limit cycles are obtained respectively for the threshold parameters. Data
are described satisfactorily up to CM momenta of about $p \sim m_\pi$.


title: Covariant Effective Field Theory for Nuclear Structure and Currents

abstract:
  Recent progress in Lorentz-covariant quantum field theories of the nuclear
many-body problem (quantum hadrodynamics or QHD) is discussed. The effective
field theory studied here contains nucleons, pions, isoscalar scalar (\sigma)
and vector (\omega) fields, and isovector vector (\rho) fields. The theory
exhibits a nonlinear realization of spontaneously broken SU(2) \times SU(2)
chiral symmetry and has three desirable features: it uses the same degrees of
freedom to describe the nuclear currents and the strong-interaction dynamics,
it satisfies the symmetries of the underlying theory of QCD, and its parameters
can be calibrated using strong-interaction phenomena, like hadron scattering or
the empirical properties of finite nuclei. Moreover, it has recently been
verified that for normal nuclear systems, it is possible to expand the
effective lagrangian systematically in powers of the meson fields (and their
derivatives) and to truncate the expansion reliably after the first few orders.
Using a mean-field version of the energy functional, accurate quantitative
results are obtained for the bulk and single-particle properties of medium- and
heavy-mass nuclei. The importance of modern perspectives in effective field
theory and density functional theory for understanding these successes of QHD
is emphasized. The inclusion of hadronic electromagnetic structure and of
nonanalytic terms in the energy functional is also considered briefly.
Weak-interaction currents are also studied in this QHD framework. Expressions
for the axial-vector current, evaluated through the first few orders in the
field expansion, satisfy both PCAC and the Goldberger--Treiman relation.
Moreover, the corresponding vector and axial-vector charges satisfy the
familiar chiral charge algebra to all orders in the pion field.


title: Relativistic quantum mechanics: A Dirac's point-form inspired approach

abstract:
  This paper describes a tentative relativistic quantum mechanics approach
inspired by Dirac's point-form, which is based on the physics description on a
hyperboloid surface. It is mainly characterized by a non-standard relation of
the constituent momenta of some system to its total momentum. Contrary to
instant- and front-form approaches, where it takes the form of a 3-dimensional
delta function, the relation is given here by a Lorentz-scalar constraint.
Thus, in the c.m. frame, the sum of the constituent momenta, which differs from
zero off-energy shell, has no fixed direction, in accordance with the absence
of preferred direction on a hyperboloid surface. To some extent, this gives
rise to an extra degree of freedom entering the description of the system of
interest. The development of a consistent formalism within this picture is
described. Comparison with other approaches is made.


title:
Form factors of hadronic systems in various forms of relativistic
  quantum mechanics

abstract:
  The form factor of hadronic systems in various forms of relativistic quantum
mechanics is considered. Motivated by the agreement of the nucleon
``point-form'' results with experiment, results for a toy model corresponding
to the simplest Feynman diagram are first presented. These ones include the
results for this diagram, which plays the role of an experiment, for the
front-form and instant-form in standard kinematics (q^+=0 and Breit frame), but
also in unconventional kinematics and finally a Dirac's point-form inspired
approach. Results for an earlier ``point-form'' approach are reminded. Results
are also presented for the pion charge form factor. Conclusions as for the
efficiency of various approaches are given.


title: Nuclei of Double-Charm Hyperons

abstract:
  The ground states of double-charm hyperons form a spin 1/2 isospin 1/2
multiplet analogous to that of nucleons. Their main strong interaction may be
inferred directly from the corresponding nucleon-nucleon interaction by
multiplication of the interaction components by the appropriate fractional
difference between interaction strengths for pairs of light flavor quarks and
pairs of triplets, e.g. nucleons, of light flavor quarks. By construction of
the interaction between the recently discovered double-charm hyperons by this
method from several realistic nucleon-nucleon interaction models it is shown
that double-charm hyperons are likely to form bound (or possibly meta-stable)
states akin to the deuteron in the spin triplet state. Double beauty baryons
would form corresponding deeply bound states. Nucleons and double charm
(beauty) hyperons will also form bound states. The existence of hypernuclei
with double-charm and double-beauty hyperons, which are stable against the
strong decay, is very likely.


title: Uncorrelated scattering approximation revisited

abstract:
  The formalism to describe the scattering of a weakly bound projectile nucleus
by a heavy target is investigated, using the Uncorrelated Scattering
Approximation. The main assumption involved is to neglect the correlation
between the fragments of the projectile in the region where the interaction
with the target is important. It is shown that the angular momentum of each
fragment with respect to the target is conserved. Moreover, when suitable
approximations are assumed, the kinetic energy of each fragment is also shown
to be conserved. The S-matrix for the scattering of the composite system can be
written as a combination of terms, each one being proportional to the product
of the S-matrices of the fragments.


title: Mesonic Content of the Nucleon and the Roper Resonance

abstract:
  We investigate colorless (mesonic)
  3q-q qbar components in the nucleon and the Roper resonance N*(1440).
  Starting from constituent quarks and gluons we estimate the excitation of
quark-antiquark pairs in a gluon exchange model with the strong coupling
constant extracted from a comparison with a non-perturbative resonating group
calculation of the pi, eta, rho and omega content of the nucleon. Applying the
same model to the Roper resonance, we find as the most striking result a very
strong scalar-isoscalar sigma content of the N*(1440) with a strength of the
3q-q qbar configurations comparable to the 3q component itself.


title: Can hadronic rescattering explain the "jet quenching" at RHIC?

abstract:
  Recent RHIC data have shown novel nuclear modifications of moderate to high
pt particle production in central Au+Au collisions, including a suppression of
hadron production and a disappearance of back-to-back hadron pairs. In this
paper, we investigate whether final-state hadronic interactions of the jet
fragments can reproduce the RHIC data. We find that hadronic rescattering can
account for the disappearance of back-to-back hadron pairs, but cannot
reproduce other features of the RHIC data.


title:
New results for the missing quantum numbers labeling the quadrupole and
  octupole boson basis

abstract:
  The many $2^k$-pole boson states, $|N_kv_k\alpha_k I_kM_k>$ with $k=2,3$,
realize the irreducible representation (IR) for the group reduction chains
$SU(2k+1)\supset R_{2k+1}\supset R_3\supset R_2$. They have been analytically
studied and widely used for the description of nuclear systems. However, no
analytical expression for the degeneracy $d_v(I)$ of the $R_{2k+1}$'s IR,
determined by the reduction $R_{2k+1}\supset R_3$, is available. Thus, the
number of distinct values taken by $\alpha_k$ has been so far obtained by
solving some complex equations. Here we derive analytical expressions for the
degeneracy $d_v(I)$ characterizing the octupole and quadrupole boson states,
respectively. The merit of this work consists of the fact that it completes the
analytical expressions for the $2^k$-pole boson basis.


title:
Two neutrino positron double beta decay of $^{106}$Cd for $0^+ \to 0^+$
  transition

abstract:
  The two neutrino positron double beta decay of $^{106}$Cd for 0$^{+} \to $
0$^{+}$ transition has been studied in the Hartree-Fock-Bogoliubov model in
conjunction with the summation method. In the first step, the reliability of
the intrinsic wave functions of $^{106}$Cd and $^{106}$Pd nuclei has been
tested by comparing the theoretically calculated results for yrast spectra,
reduced $B(E2$:$0^{+}\to 2^{+})$ transition probabilities, quadrupole moments
$Q(2^{+})$ and gyromagnetic factors $g(2^{+})$ with the available experimental
data. In the second step, the nuclear transition matrix element $M_{2\nu}$ and
the half-life $T_{1/2}^{2\nu}$ for 0$^{+}\to$ 0$^{+}$ transition have been
calculated with these wave functions. Moreover, we have studied the effect of
deformation on nuclear transition matrix element M$_{2\nu}.$


title:
Large transverse momentum suppression of $\pi^0$'s in Au+Au and d+Au
  collisions at $\sqrt{s}=200$ GeV

abstract:
  We propose a model of suppression of $\pi^0$'s based on two different
effects: at low $p_T$ we take into account the shadowing corrections, while at
large $p_T$ the suppression is produced due to the interaction of the large
$p_T$ pion with the dense medium created in the collision. The main features of
the data on $AuAu$ and $dAu$ collisions are reproduced both at mid and at
forward rapidities.


title: Centrality Dependence of Chemical Freeze-out in Au+Au Collisions at RHIC

abstract:
  We will report centrality dependence of chemical freeze-out temperature
($T_{ch}$), light quark chemical potential ($\mu_{q}$), strange quark chemical
potential ($\mu_{s}$), and strangeness saturation factor ($\gamma_{s}$) in
Au+Au collisions at $\sqrt{s_{NN}}$ = 130 and 200 GeV. A systematic study for
combination of ratios for chemical freeze-out fit is studied and we have found
small ombination dependences. The results show $\gamma_{s}$ increasing with
centrality but the other parameters have less sensitivity to the centralities.


title: $J$-pairing Interactions of Fermions in a Single-$j$ Shell

abstract:
  In this talk I shall introduce our recent works on general pairing
interactions and pair truncation approximations for fermions in a single-j
shell, including the spin zero dominance, features of eigenvalues of fermion
systems in a single-j shell interacting by a $J-$pairing interaction.


title: Relation between the density-matrix theory and the pairing theory

abstract:
  The time-dependent density-matrix theory (TDDM) gives a correlated ground
state as a stationary solution of the time-dependent equations for one-body and
two-body density matrices. The small amplitude limit of TDDM (STDDM) is a
version of extended RPA theories which include the effects of ground state
correlations. It is shown that the solutions of the Hartree-Fock Bogoliubov
theory and the quasi-particle RPA satisfy the TDDM and STDDM equations,
respectively, when only pairing-type correlations are taken into account in
TDDM and STDDM.


title:
Many-body systems in the presence of the random interaction and the $J$
  pairing interaction

abstract:
  In this talk I shall discuss some regularities of many-body systems in the
presence of random interactions and regularities of a single-$j$ shell for the
$J$ pairing interaction which works only when two particles are coupled to spin
$J$. I shall first explain an empirical rule to predict the spin $I$ ground
state probability.
  Then I shall present some interesting results of a single-$j$ shell under the
$J$ pairing interaction. Last I shall discuss some preliminary results of
binding energies in the presence of random two-body interactions.


title:
Ground state spin 0$^+$ dominance of many-body systems with random
  interactions and related topics

abstract:
  In this talk we shall show our recent results in understanding the spin$^{\rm
parity}$ 0$^+$ ground state (0 g.s.) dominance of many-body systems. We propose
a simple approach to predict the spin $I$ g.s. probabilities which does not
require the diagonalization of a Hamiltonian with random interactions. Some
findings related to the 0 g.s. dominance will also be discussed.


title: Physical region for three-neutrino mixing angles

abstract:
  We derive a set of symmetry relations for the three-neutrino mixing angles,
including the MSW matter effect. Though interesting in their own right, these
relations are used to choose the physical region of the mixing angles such that
oscillations are parameterized completely and uniquely. We propose that the
preferred way of setting the bounds on the mixing angles should be $\theta_{12}
\in [0,\pi/2]$, $\theta_{13} \in [-\pi/2,\pi/2]$, $\theta_{23}\in [0,\pi/2]$,
and $\delta \in [0,\pi)$. No CP violation then results simply from setting
$\delta=0$. In the presence of the MSW effect, this choice of bounds is a new
result. Since the size of the asymmetry about $\theta_{13} = 0$ is dependent on
the details of the data analysis and is a part of the results of the analysis,
we argue that the negative values of $\theta_{13}$ should not be ignored.


title:
Two neutrino double $\beta$ decay of 94v$\leq A\leq $110 nuclei for $0^+
  \to 0^+$ transition

abstract:
  The two neutrino double beta decay of $ ^{94,96}$Zr$,^{98,100}$Mo$,^{104}$%
Ru and $ ^{110}$Pd nuclei for $0^{+}\to 0^{+}$ transition is studied in the
PHFB model in conjunction with the summation method. In the first step, the
reliability of the intrinsic wave functions has been established by obtaining
an overall agreement between a number of theoretically calculated spectroscopic
properties and the available experimental data for $ ^{94,96}$%
Zr$,^{94,96,98,100}$Mo, $^{98,100,104}$Ru, $^{104,110}$Pd and $^{110}$Cd
isotopes. Subsequently, the PHFB wave functions of the above mentioned nuclei
are employed to calculate the nuclear transition matrix elements $M_{2\nu}$ as
well as half-lives $T{_{1/2}^{2\nu}}$. Further, we have studied the effects of
deformation on the $M_{2\nu}$.


title:
Calculations of K+, K- and phi Production in Near-Threshold
  Proton-Nucleus Collisions

abstract:
  K+, K- and \phi meson production in proton-nucleus (pA) collisions has been
calculated within a BUU transport model. It is shown that the nucleon-hyperon
strangeness transfer channel is essential. The role of three-body reactions has
been investigated within the medium. The targetmass dependence of $\phi$
production is predicted to give important information on the in-medium
properties of all three mesons.


title: Spin-one Color Superconductivity in Cold and Dense Quark Matter

abstract:
  In this thesis, several color-superconducting phases where quarks of the same
flavor form Cooper pairs are investigated. In these phases, a Cooper pair
carries total spin one. A systematic classification of theoretically possible
phases, discriminated by the color-spin structure of the order parameter and
the respective symmetry breaking pattern, is presented. In the weak-coupling
limit, i.e., for asymptotically high densities, a universal form of the QCD gap
equation is derived, applicable to arbitrary color-superconducting phases. It
is applied to several spin-one and spin-zero phases in order to determine their
energy gaps and critical temperatures. In some of the spin-one phases the
resulting gap function is anisotropic and has point or line nodes. It is shown
that the phases with two different gaps violate the well-known BCS relation
between the critical temperature and the zero-temperature gap. Moreover, the
screening properties of color superconductors regarding gluons and photons are
discussed. In particular, it turns out that, contrary to spin-zero color
superconductors, spin-one color superconductors exhibit an electromagnetic
Meissner effect. This property is proven by symmetry arguments as well as by an
explicit calculation of the gluon and photon Meissner masses.

categories: nucl-th astro-ph cond-mat.supr-con hep-ph


title:
Explicit Delta(1232) Degrees of Freedom in Compton Scattering off the
  Deuteron

abstract:
  We examine elastic Compton scattering off the deuteron for photon energies
between 50 MeV and 100 MeV in the framework of chiral effective field theories
to next-to-leading order. We compare one theoretical scheme with only pions and
nucleons as explicit degrees of freedom to another in which the Delta(1232)
resonance is treated as an explicit degree of freedom. Whereas pion degrees of
freedom suffice to describe the experimental data measured at about 70 MeV, the
explicit Delta(1232) gives important contributions that help to reproduce the
angular dependence at higher energies. The static isoscalar dipole
polarizabilities alpha_E^s and beta_M^s are fitted to the available data,
giving results for the neutron polarizabilities
alpha_E^n=(14.2+-2.0(stat)+-1.9(syst))*10^(-4)fm^3,
beta_M^n=(1.8+-2.2(stat)+-0.3(syst))*10^(-4)fm^3. These values are in good
agreement with previous experimental analyses. Comparing them to the well-known
proton values we conclude that there is currently no evidence for significant
differences between the proton and neutron electromagnetic dipole
polarizabilities.


title: Clustering aspects and the shell model

abstract:
  In this talk I shall discuss the clustering aspect and the shell model. I
shall first discuss the $\alpha$-cluster aspects based on the shell model
calculations. Then I shall discuss the spin zero ground state dominance in the
presence of random interactions and a new type of cluster structure for
fermions in a single-$j$ shell in the presence of only pairing interaction with
the largest multiplicity.


title: A General Effective Action for High-Density Quark Matter

abstract:
  We derive a general effective action for quark matter at nonzero temperature
and/or nonzero density. For this purpose, we distinguish irrelevant from
relevant quark modes, as well as hard from soft gluon modes by introducing two
separate cut-offs in momentum space, one for quarks, $\Lambda_q$, and one for
gluons, $\Lambda_g$. We exactly integrate out irrelevant quark modes and hard
gluon modes in the functional integral representation of the QCD partition
function. Depending on the specific choice for $\Lambda_q$ and $\Lambda_g$, the
resulting effective action contains well-known effective actions for hot and/or
dense quark matter, for instance the ``Hard Thermal Loop'' or the ``Hard Dense
Loop'' action, as well as the high-density effective theory proposed by Hong
and others. We then apply our effective action to review the calculation of the
color-superconducting gap parameter to subleading order in weak coupling, where
the strong coupling constant $g \ll 1$. In this situation, relevant quark modes
are those within a layer of thickness $2 \Lambda_q$ around the Fermi surface.
The non-perturbative nature of the gap equation invalidates naive attempts to
estimate the importance of the various contributions via power counting on the
level of the effective action. Nevertheless, once the gap equation has been
derived within a particular many-body approximation scheme, the cut-offs
$\Lambda_q, \Lambda_g$ provide the means to rigorously power count different
contributions to the gap equation. We recover the previous result for the QCD
gap parameter for the choice $\Lambda_q \alt g \mu \ll \Lambda_g \alt \mu$,
where $\mu$ is the quark chemical potential. We also point out how to improve
this result beyond subleading order in weak coupling.


title:
Modified Bethe-Weizsacker mass formula with isotonic shift and new
  driplines

abstract:
  Nuclear masses are calculated using the modified Bethe-Weizsacker mass
formula in which the isotonic shifts have been incorporated. The results are
compared with the improved liquid drop model with isotonic shift. Mass excesses
predicted by this method compares well with the microscopic-macroscopic model
while being much more simple. The neutron and proton drip lines have been
predicted using this modified Bethe-Weizsacker mass formula with isotonic
shifts.


title:
Calculation of the Momentum Dependence of Hadronic Current Correlation
  Functions at Finite Temperature

abstract:
  We have calculated spectral functions associated with hadronic current
correlation functions for vector currents at finite temperature. We made use of
a model with chiral symmetry, temperature-dependent coupling constants and
temperature-dependent momentum cutoff parameters. Our model has two parameters
which are used to fix the magnitude and position of the large peak seen in the
spectral functions. In our earlier work, good fits were obtained for the
spectral functions that were extracted from lattice data by means of the
maximum entropy method (MEM). In the present work we extend our calculations
and provide values for the three-momentum dependence of the vector correlation
function at T=1.5T_c. These results are used to obtain the correlation function
in coordinate space, which is usually parametrized in terms of a screening
mass. Our results for the three-momentum dependence of the spectral functions
are similar to those found in a recent lattice QCD calculation for charmonium
[S. Datta, F. Karsch, P. Petreczky and I. Wetzorke, hep-lat/0312037]. For a
limited range we find the exponential behavior in coordinate space that is
usually obtained for the spectral function for T>T_c and which allows for the
definition of a screening mass.


title: Charge Form Factors of Quark-Model Pions II

abstract:
  Experimental data of the pion charge form factor are well represented by
Poincar\'e invariant constituent-quark phenomenology depending on two
parameters, a confinement scale and an effective constituent--quark mass. Pion
states are represented by eigenfunctions of mass and spin operators and of the
light-front momenta. An effective current density is generated by the dynamics
from a null-plane impulse current density. A simple shape of the wave function
depending only on the confinement scale is sufficient.


title:
Multiplicity Distributions of Intermediate Mass Fragments in the
  Thermodynamic Model

abstract:
  Multiplicity distributions of intermediate mass fragments (IMF) seen in
intermediate energy heavy ion collisions have been of great interest in the
last ten years. The distributions of single intermediate sized element are
close to Poissonian and have been subjected to widely different physical
interpretations. We calculate the multiplicity distributions in a thermodynamic
model whose physical basis is equal population in phase space which implies
equilibrium statistics. We found distributions of single element are to a good
approximation Poissonian, and such result is attributed to the small emission
probability of a given IMF among all the possible channels. We also found
significant deviation from Poisson distribution for a range of IMFs, and
suggest strong correlations as an explanation. Systematics of the multiplicity
distributions are explored in both one component and two component models. In
one component model, sudden changes for the multiplicity distributions are
found at the phase transition region. In two component model, the multiplicity
distributions have more subtleties. Results from the current model are compared
with available data, and good agreements are found. New signals for the
multi-particle correlations are also suggested.


title: Generalized Richardson-Gaudin Nuclear Models

abstract:
  The exact solvability of several nuclear models with non-degenerate
single-particle energies is outlined and leads to a generalization of
integrable Richardson-Gaudin models, like the $su(2)$-based fermion pairing, to
any simple Lie algebra. As an example, the $so(5)\sim sp(4)$ model of T=1
pairing is discussed and illustrated for the case of $^{64}$Ge with
non-degenerate single-particle energies.


title: Asymmetric Colliding Nuclear Matter Approach in Heavy Ion Collisions

abstract:
  The early stage of a heavy ion collision is governed by local non-equilibrium
momentum distributions which have been approximated by colliding nuclear matter
configurations, i.e. by two Lorentz elongated Fermi ellipsoids. This approach
has been extended from the previous assumption of symmetric systems to
asymmetric 2-Fermi sphere configurations, i.e. to different densities. This
provides a smoother transition from the limiting situation of two
interpenetrating currents to an equilibrated system. The model is applied to
the dynamical situations of heavy ion collisions at intermediate energies
within the framework of relativistic transport (RBUU) calculations. We find
that the extended colliding nuclear matter approach is more appropriate to
describe collective reaction dynamics in terms of flow observables, in
particular, for the elliptic flow at low energies.


title:
Two-pion production processes, chiral symmetry and NN interaction in the
  medium

abstract:
  We study the two-pion propagator in the nuclear medium. This quantity appears
in the $\pi-\pi$ T-matrix and we show that it also enters the QCD scalar
susceptibility. The medium effects on this propagator are due to the influence
of the individual nucleon response to a scalar field through their pion clouds.
This response is appreciably increased by the nuclear environment. It produces
an important convergence effect between the scalar and pseudoscalar
susceptibilities, reflecting the reshaping of the scalar strengh observed in
$2\pi$ production experiments. While a large modification of the $\sigma$
propagator follows, due to its coupling to two pion states, we show that the NN
potential remains instead unaffected.


title: Ultra-cold Neutron Production in Anti-ferromagnetic Oxygen Solid

abstract:
  Spin waves, or magnons, in the anti-ferromagnetic $\alpha$ phase of solid
oxygen provide a novel mechanism for ultra-cold neutron (UCN) production.
Magnons dominate the energy exchange mechanisms for cold neutrons and UCN in
solid $\alpha$-oxygen, much in the same way as do phonons in solid deuterium
superthermal UCN sources. We present calculations of UCN production and
upscattering rates in S-O$_2$. The results indicate that S-O$_2$ is potentially
a much more efficient UCN source material than solid deuterium.


title: W(5): Wobbling Mode in the Framework of the X(5) Model

abstract:
  Using in the Bohr Hamiltonian the approximations leading to the Bohr and
Mottelson description of wobbling motion in even nuclei, a W(5) model for
wobbling bands, coexisting with a X(5) ground state band, is obtained.
Separation of variables is achieved by assuming that the relevant potential has
a sharp minimum at gamma_0, which is the only parameter entering in the spectra
and B(E2) transition rates (up to overall scale factors). B(E2) transition
rates exhibit the features expected in the wobbling case, while the spectrum
for gamma_0=20 degrees is in good agreement with experimental data for Dy-156.


title:
On the Isovector Channels in Relativistic Point Coupling Models within
  the Hartree and Hartree-Fock Approximations

abstract:
  We investigate the consequences of Fierz transformations acting upon the
contact interactions for nucleon fields occurring in relativistic point
coupling models in Hartree approximation, which yield the same models but in
Hartree-Fock approximation instead. We find for four-fermion interactions
occurring in two existing relativistic point coupling phenomenologies that
whereas in Hartree the isovector-scalar strength, corresponding to delta-meson
exchange, is unnaturally small, indicating a possible new symmetry, in
Hartree-Fock it is instead comparable to the isovector-vector strength
corresponding to rho-meson exchange, but the sum of the two isovector coupling
constants appears to be preserved in both approaches. Furthermore, in
Hartree-Fock approximation, both QCD-scaled isovector coupling constants are
natural (dimensionless and of order 1) whereas in Hartree approximation only
that of the isovector-vector channel is natural. This indicates that it is not
necessary to search for a new symmetry and, moreover, that the role of the
delta-meson should be reexamined.


title:
Generalization of the $N_pN_n$ Scheme and the Structure of the Valence
  Space

abstract:
  The $N_pN_n$ scheme, which has been extensively applied to even-even nuclei,
is found to be a very good benchmark for odd-even, even-odd, and doubly-odd
nuclei as well. There are no apparent shifts in the correlations for these four
classes of nuclei. The compact correlations highlight the deviant behavior of
the Z=78 nuclei, are used to deduce effective valence proton numbers near Z=64,
and to study the evolution of the Z=64 subshell gap.


title:
Effective theories of scattering with an attractive inverse-square
  potential and the three-body problem

abstract:
  A distorted-wave version of the renormalisation group is applied to
scattering by an inverse-square potential and to three-body systems. In
attractive three-body systems, the short-distance wave function satisfies a
Schroedinger equation with an attractive inverse-square potential, as shown by
Efimov. The resulting oscillatory behaviour controls the renormalisation of the
three-body interactions, with the renormalisation-group flow tending to a limit
cycle as the cut-off is lowered. The approach used here leads to single-valued
potentials with discontinuities as the bound states are cut off. The
perturbations around the cycle start with a marginal term whose effect is
simply to change the phase of the short-distance oscillations, or the
self-adjoint extension of the singular Hamiltonian. The full power counting in
terms of the energy and two-body scattering length is constructed for
short-range three-body forces.


title:
Deformation Projected RMF Calculation for Cr and Fe nuclei in Hybrid
  Derivative Coupling Model

abstract:
  The ground state properties of even mass Cr and Fe isotopes are studied using
the generalized hybrid derivative coupling model. The energy surface of each
isotope is plotted as a function of the mass quadrupole moment. The neutron
numbers N=20 and N=40 are seen to remain magic numbers but N= 28 and 50 are
predicted to be non-magic. The neutron number N=70 turns out to be a magic
number according to the present calculation. In all the isotopes studied the
calculated binding energy values are less than those obtained from experiment
while the deformation is in better agreement.


title: Spectral function at high missing energies and momenta

abstract:
  The nuclear spectral function at high missing energies and momenta has been
determined from a self-consistent calculation of the Green's function in
nuclear matter using realistic nucleon-nucleon interactions. The results are
compared with recent experimental data derived from ($e,e'p$) reactions on
$^{12}C$. A rather good agreement is obtained if the Green's functions are
calculated in a non-perturbative way.


title: Determination of S17(0) from published data

abstract:
  The experimental landscape for the 7Be+p radiative capture reaction is
rapidly changing as new high precision data become available. We present an
evaluation of existing data, detailing the treatment of systematic errors and
discrepancies, and show how they constrain the astrophysical S factor (S17),
independent of any nuclear structure model. With theoretical models robustly
determining the behavior of the sub-threshold pole, the extrapolation error can
be reduced and a constraint placed on the slope of S17. Using only radiative
capture data, we find S17(0) = 20.7 +/- 0.6 (stat) +/- 1.0 (syst) eV b if data
sets are completely independent, while if data sets are completely correlated
we find S17(0) = 21.4 +/- 0.5 (stat) +/- 1.4 (syst) eV b. The truth likely lies
somewhere in between these two limits. Although we employ a formalism capable
of treating discrepant data, we note that the central value of the S factor is
dominated by the recent high precision data of Junghans et al., which imply a
substantially higher value than other radiative capture and indirect
measurements. Therefore we conclude that further progress will require new high
precision data with a detailed error budget.


title: Supernova Neutrino-Nucleus Physics and the r-process

abstract:
  This talk reviews three inputs important to neutrino-induced nucleosynthesis
in a supernova: 1) "standard" properties of the supernova neutrino flux, 2)
effects of phenomena like neutrino oscillations on that flux, and 3) nuclear
structure issues in estimating cross sections for neutrino-nucleus
interactions. The resulting possibilities for neutrino-induced nucleosynthesis
-- the neutrino-process -- in massive stars are discussed. This includes two
relatively recent extensions of neutrino-process calculations to heavier
nuclei, one focused on understanding the origin of 138La and 180Ta and the
second on the effects following r-process freezeout. From calculations of the
neutrino post-processing of the r-process distribution, limits can be placed on
the neutrino fluence after freezeout and thus on the dynamic timescale for the
expansion of the "hot bubble."


title:
Consequences of self-consistency violations in Hartree-Fock random-phase
  approximation calculations of the nuclear breathing mode energy

abstract:
  We provide for the first time accurate assessments of the consequences of
violations of self-consistency in the Hartree-Fock based random phase
approximation (RPA) as commonly used to calculate the energy $E_c$ of the
nuclear breathing mode. Using several Skyrme interactions we find that the
self-consistency violated by ignoring the spin-orbit interaction in the RPA
calculation causes a spurious enhancement of the breathing mode energy for spin
unsaturated systems. Contrarily, neglecting the Coulomb interaction in the RPA
or performing the RPA calculations in the TJ scheme underestimates the
breathing mode energy. Surprisingly, our results for the $^{90}$Zr and
$^{208}$Pb nuclei for several Skyrme type effective nucleon-nucleon
interactions having a wide range of nuclear matter incompressibility ($K_{nm}
\sim 215 - 275$ MeV) and symmetry energy ($J \sim 27 - 37$ MeV) indicate that
the net uncertainty ($\delta E_c \sim 0.3$ MeV) is comparable to the
experimental one.


title:
The dielectric function excited by $\rho NN$ tensor coupling in nuclear
  matter

abstract:
  The dielectric function of nuclear matter excited by $\rho NN$ tensor
coupling has been studied in the framework of Finite temperature field theory.
The induced current mechanism has been introduced to explain the three extrema
on the dielectric function curve, of which one is in the space-like region and
the other two are in the time-like region. It points out that the tensor
coupling contributes much more large amplitude than the vector coupling and
plays a more important role on the time-like region compared with its effect on
the space-like region.


title: Axial Transition Form Factors and Pion Decay of Baryon Resonances

abstract:
  The pion decay constants of the lowest orbitally excited states of the
nucleon and the $\Delta(1232)$ along with the corresponding axial transition
form factors are calculated with Poincar\'e covariant constituent-quark models
with instant, point and front forms of relativistic kinematics. The model wave
functions are chosen such that the calculated electromagnetic and axial form
factors of the nucleon represent the empirical values in all three forms of
kinematics, when calculated with single-constituent currents. The pion decay
widths calculated with the three forms of kinematics are smaller than the
empirical values. Front and instant form kinematics provide a similar
description, with a slight preference for front form, while the point form
values are significantly smaller in the case of the lowest positive parity
resonances.


title: Thermal Photons in Strong Interactions

abstract:
  A brief survey is given on the current status of evaluating thermal
production of photons from a strongly interacting medium. Emphasis is put on
recent progress in assessing equilibrium emission rates in both hadronic and
quark-gluon matter. We also give an update on the status of comparing
theoretical calculations with experimental data from heavy-ion collisions at
the SPS, as well as prospects for RHIC. Finally, applications of photon rate
calculations to colorsuperconducting quark matter are discussed.


title: Contact interaction in the nonrelativistic pion absorption operator

abstract:
  Chirally invariant Lagrangian containing nucleon, pion and chiral scalar
fields is considered. A consistent scheme is proposed for obtaining the
nonrelativistic operator of pion absorption by NN-pair taking into account the
chiral scalar exchange. An important role of the contact interaction is pointed
out.D


title: Collective Flow signals the Quark Gluon Plasma

abstract:
  A critical discussion of the present status of the CERN experiments on charm
dynamics and hadron collective flow is given. We emphasize the importance of
the flow excitation function from 1 to 50 A$\cdot$GeV: here the hydrodynamic
model has predicted the collapse of the $v_1$-flow and of the $v_2$-flow at
$\sim 10$ A$\cdot$GeV; at 40 A$\cdot$GeV it has been recently observed by the
NA49 collaboration. Since hadronic rescattering models predict much larger flow
than observed at this energy we interpret this observation as potential
evidence for a first order phase transition at high baryon density $\rho_B$. A
detailed discussion of the collective flow as a barometer for the equation of
state (EoS) of hot dense matter at RHIC follows. Additionally, detailed
transport studies show that the away-side jet suppression can only partially
($<$ 50%) be due to hadronic rescattering. We, finally, propose upgrades and
second generation experiments at RHIC which inspect the first order phase
transition in the fragmentation region, i.e. at $\mu_B \approx 400$ MeV ($y
\approx 4-5$), where the collapse of the proton flow should be seen in analogy
to the 40 A$\cdot$GeV data. The study of Jet-Wake-riding potentials and Bow
shocks -- caused by jets in the QGP formed at RHIC -- can give further
information on the equation of state (EoS) and transport coefficients of the
Quark Gluon Plasma (QGP).


title: Super-Radiance: From Nuclear Physics to Pentaquarks

abstract:
  The phenomenon of super-radiance in quantum optics predicted by Dicke 50
years ago and observed experimentally has its counterparts in many-body systems
on the borderline between discrete spectrum and continuum. The interaction of
overlapping resonances through the continuum leads to the redistribution of
widths and creation of broad super-radiant states and long-lived compound
states. We explain the physics of super-radiance and discuss applications to
weakly bound nuclei, giant resonances and widths of exotic baryons.


title:
Exclusive Electro-Disintegration of 3He at High Q2: I. Generalized
  Eikonal Approximation

abstract:
  We develop a theoretical framework for calculation of high $Q^2$ exclusive
electro-disintegration of A=3 systems. The main result of this work is the
calculation of the final state interaction of the struck energetic nucleon with
recoil nucleons within the generalized eikonal approximation (GEA) which allows
us to account for the finite and relatively large momenta of the bound nucleons
in the nucleus. The important advantage of this approach is the possibility to
study in a self-consistent way the short range correlations in nuclei. This is
due to the fact that GEA does not require a stationary condition for recoil
nucleons as conventional Glauber approximation does. As a result GEA treats
explicitly the Fermi motion of recoil nucleons in the nucleus.


title:
Nuclear Structure based on Correlated Realistic Nucleon-Nucleon
  Potentials

abstract:
  We present a novel scheme for nuclear structure calculations based on
realistic nucleon-nucleon potentials. The essential ingredient is the explicit
treatment of the dominant interaction-induced correlations by means of the
Unitary Correlation Operator Method (UCOM). Short-range central and tensor
correlations are imprinted into simple, uncorrelated many-body states through a
state-independent unitary transformation. Applying the unitary transformation
to the realistic Hamiltonian leads to a correlated, low-momentum interaction,
well suited for all kinds of many-body models, e.g., Hartree-Fock or
shell-model. We employ the correlated interaction, supplemented by a
phenomenological correction to account for genuine three-body forces, in the
framework of variational calculations with antisymmetrised Gaussian trial
states (Fermionic Molecular Dynamics). Ground state properties of nuclei up to
mass numbers A<~60 are discussed. Binding energies, charge radii, and charge
distributions are in good agreement with experimental data. We perform angular
momentum projections of the intrinsically deformed variational states to
extract rotational spectra.


title: Instabilities in asymmetric nuclear matter

abstract:
  The existence of phase transitions from liquid to gas phases in asymmetric
nuclear matter (ANM) is related with the instability regions which are limited
by the spinodals. In this work we investigate the instabilities in ANM
described within relativistic mean field hadron models, both with constant and
density dependent couplings at zero and finite temperatures. In calculating the
proton and neutron chemical potentials we have used an expansion in terms of
Bessel functions that is convenient at low densities. The role of the isovector
scalar $\delta$-meson is also investigated in the framework of relativistic
mean field models and density dependent hadronic models. It is shown that the
main differences occur at finite temperature and large isospin asymmetry close
to the boundary of the instability regions.


title: Hadron attenuation in deep inelastic lepton-nucleus scattering

abstract:
  We present a detailed theoretical investigation of hadron attenuation in deep
inelastic scattering (DIS) off complex nuclei in the kinematic regime of the
HERMES experiment. The analysis is carried out in the framework of a
probabilistic coupled-channel transport model based on the
Boltzmann-Uehling-Uhlenbeck (BUU) equation, which allows for a treatment of the
final-state interactions (FSI) beyond simple absorption mechanisms.
Furthermore, our event-by-event simulations account for the kinematic cuts of
the experiments as well as the geometrical acceptance of the detectors. We
calculate the multiplicity ratios of charged hadrons for various nuclear
targets relative to deuterium as a function of the photon energy nu, the hadron
energy fraction z_h=E_h/nu and the transverse momentum p_T. We also confront
our model results on double-hadron attenuation with recent experimental data.
Separately, we compare the attenuation of identified hadrons (pi^\pm, \pi^0,
K^\pm, p and pbar) on Ne and Kr targets with the data from the HERMES
Collaboration and make predictions for a Xe target. At the end we turn towards
hadron attenuation on Cu nuclei at EMC energies. Our studies demonstrate that
(pre-)hadronic final-state interactions play a dominant role in the kinematic
regime of the HERMES experiment while our present approach overestimates the
attenuation at EMC energies.


title: Field theory Lagrangian approach to nuclear structure

abstract:
  We show that in the search of a unified mean field description of finite
nuclei and of nuclear and neutron matter even at high densities, the
relativistic nuclear model derived from effective field theory and density
functional theory methods constitutes a competitive framework. The model
predicts a soft equation of state, owing to the additional meson interaction
terms, consistently with the results of the microscopic
Dirac-Brueckner-Hartree-Fock theory and recent experimental observations from
heavy ion collisions. In finite systems, after inclusion of the pairing
correlations, the model is able to describe both stable and exotic nuclei. We
address two examples at the limits of the nuclear landscape. On the one hand,
we analyze the giant halo effect and the isoscalar giant monopole resonance in
very neutron-rich Zr isotopes. On the other hand, we discuss the structure of
superheavy nuclei with double shell closures.


title:
Damped collective motion of isolated many body systems within a
  variational approach to functional integrals

abstract:
  Two improvements with respect to previous formulations are presented for the
calculation of the partition function $\mathcal{Z}$ of small, isolated and
interacting many body systems. By including anharmonicities and employing a
variational approach quantum effects can be treated even at very low
temperatures. A method is proposed of how to include collisional damping.
Finally, our approach is applied to the calculation of the decay rate of
metastable systems.


title:
The Nucleon-Mass Difference in Chiral Perturbation Theory and Nuclear
  Forces

abstract:
  A new method is developed for treating the effect of the neutron-proton mass
difference in isospin-violating nuclear forces. Previous treatments utilized an
awkward subtraction scheme to generate these forces. A field redefinition is
used to remove that mass difference from the Lagrangian (and hence from
asymptotic nucleon states) and replace its effect by effective interactions.
Previous calculations of static Class II charge-independence-breaking and Class
III charge-symmetry-breaking potentials are verified using the new scheme,
which is also used to calculate Class IV nuclear forces. Two-body forces of the
latter type are found to be identical to previously obtained results. A novel
three-body force is also found. Problems involving Galilean invariance with
Class IV one-pion-exchange forces are identified and resolved.


title: QCD Sum Rules Description of Nucleons in Asymmetric Nuclear Matter

abstract:
  We calculate the nucleon parameters in isospin asymmetric nuclear matter
using the QCD sum rules. The nucleon self-energies are expressed in terms of
the in-medium values of QCD condensates. The simple approximate expressions for
the self-energies are obtained in terms of these condensates. Relation between
successive inclusion of the condensates and the meson-exchange picture of the
nucleon interaction with medium is analyzed. The values of the self-energies
and of the symmetry energy agree with those obtained by the methods of nuclear
physics.


title: Oblate-prolate shape coexistence at finite angular momentum

abstract:
  We investigate shape coexistence in a rotating nucleus. We concentrate on the
interesting case of 72-Kr which exhibits an interesting interplay between
prolate and oblate states as a function of angular momentum. The calculation
uses the local harmonic version of the method of self-consistent adiabatic
large-amplitude collective motion. We find that the collective behaviour of the
system changes with angular momentum and we focus on the role of non-axial
shapes.


title:
Statistical nature of cluster emission in nuclear liquid-vapour phase
  coexistence

abstract:
  The emission of nuclear clusters is investigated within the framework of
isospin dependent lattice gas model and classical molecular dynamics model. It
is found that the emission of individual cluster which is heavier than proton
is almost Poissonian except near the transition temperature at which the system
is leaving the liquid-vapor phase coexistence and the thermal scaling is
observed by the linear Arrhenius plots which is made from the average
multiplicity of each cluster versus the inverse of temperature in the liquid
vapor phase coexistence. The slopes of the Arrhenius plots, {\it i.e.} the
"emission barriers", are extracted as a function of the mass or charge number
and fitted by the formula embodied with the contributions of the surface energy
and Coulomb interaction. The good agreements are obtained in comparison with
the data for low energy conditional barriers. In addition, the possible
influences of the source size, Coulomb interaction and "freeze-out" density and
related physical implications are discussed.


title: Pseudoscalar Meson Radial Excitations

abstract:
  Goldstone modes are the only pseudoscalar mesons to possess a nonzero
leptonic decay constant in the chiral limit when chiral symmetry is dynamically
broken. The decay constants of their radial excitations vanish. These features
and aspects of their impact on the meson spectrum are illustrated using a
manifestly covariant and symmetry preserving model of the kernels in the gap
and Bethe-Salpeter equations.


title:
Signals of spinodal phase decomposition in high-energy nuclear
  collisions

abstract:
  High-energy nuclear collisions produce quark-gluon plasmas that expand and
hadronize. If the associated phase transition is of first order then the
hadronization should proceed through a spinodal phase separation. We explore
here the possibility of identifying the associated clumping by analysis of
suitable N-particle momentum correlations.


title: Baryon Spectroscopy in Lattice QCD

abstract:
  We review recent developments in the study of excited baryon spectroscopy in
lattice QCD. After introducing the basic methods used to extract masses from
correlation functions, we discuss various interpolating fields and lattice
actions commonly used in the literature. We present a survey of results of
recent calculations of excited baryons in quenched QCD, and outline possible
future directions in the study of baryon spectra.


title:
Exact Analytical Solution of the Constrained Statistical
  Multifragmentation Model

abstract:
  A novel powerful mathematical method is presented, which allows us to find an
analytical solution of a simplified version of the statistical
multifragmentation model with the restriction that the largest fragment size
cannot exceed the finite volume of the system. A complete analysis of the
isobaric partition singularities is done for finite system volumes. The finite
size effects for large fragments and the role of metastable (unstable) states
are discussed.


title: Surface Partition of Large Fragments

abstract:
  The surface partition of large fragments is derived analytically within a
simple statistical model by the Laplace-Fourier transformation method. In the
limit of small amplitude deformations, a suggested Hills and Dales Model
reproduces the leading term of the famous Fisher result for the surface entropy
with an accuracy of a few percent. The surface partition of finite fragments is
discussed as well.


title:
Method of multiple internal reflections in description of tunneling
  evolution through barriers

abstract:
  A method of a non-stationary description of tunneling of a particle through
the one-dimensional and spherically symmetric rectangular barriers on the basis
of analisis of multiple internal reflections of wave packets in relation on the
barrier boundaries, named as the Method of multiple internal reflections, is
presented at the first time. For the one-dimensional problem the applicability
of this method is proved, its specific features are analyzed. For the
spherically symmetric problem the amplitudes of the transmitted and reflected
wave packets, times of tunneling and reflection in relation to the barrier are
calculated using this method. The effect of Hartman-Fletcher is analyzed.


title: Multi-quark states

abstract:
  The pentaquark state recently discovered has been discussed based on various
quark model calculations. Odd parity for the state can not be ruled out
theoretically because contributions related to non-trivial color structures
have not been studied completely. Other multiquark states, especially
dibaryons, have been discussed also. A strangeness -3 N$\Omega$ dibaryon has
been shown to have a width as small as 12-22 keV and should be detectable in
$\Omega$ high productivity reactions such as at RHIC, COMPAS and the planned
JHF and FAIR projects.


title: Origin of Borromean systems

abstract:
  The complex energies of the three-body resonances for one infinitely heavy
particle and two non-interacting light particles are the sum of the two
contributing two-body complex resonance energies. The bound state of a
Borromean system originates from a resonance when the third interaction is
introduced, a finite mass is allowed and proper angular momentum coupling is
included. The relative importance of these contributions are investigated and
the resulting structure of Borromean systems are traced back to the two-body
continuum properties. The $0^+$ and $2^+$ states in $^{6}$He result from
neutron-core p-states and the ground and first excited state of $^{11}$Li
originate from neutron-core $s^2$ and $sp$-states.


title:
Chiral approach to nuclear matter: Role of two-pion exchange with
  virtual delta-isobar excitation

abstract:
  We extend a recent three-loop calculation of nuclear matter in chiral
perturbation theory by including the effects from two-pion exchange with single
and double virtual $\Delta(1232)$-isobar excitation. Regularization dependent
short-range contributions from pion-loops are encoded in a few NN-contact
coupling constants. The empirical saturation point of isospin-symmetric nuclear
matter, $\bar E_0 = -16 $MeV, $\rho_0 = 0.16 $fm$^{-3}$, can be well reproduced
by adjusting the strength of a two-body term linear in density (and weakening
an emerging three-body term quadratic in density). The nuclear matter
compressibility comes out as $K = 304 $MeV. The real single-particle potential
$U(p,k_{f0})$ is substantially improved by the inclusion of the chiral $\pi
N\Delta$-dynamics: it grows now monotonically with the nucleon momentum $p$.
The effective nucleon mass at the Fermi surface takes on a realistic value of
$M^*(k_{f0})=0.88M$. As a consequence of these features, the critical
temperature of the liquid-gas phase transition gets lowered to the value $T_c
\simeq 15 $MeV. In this work we continue the complex-valued single-particle
potential $U(p,k_f)+i W(p,k_f)$ into the region above the Fermi surface
$p>k_f$. The effects of $2\pi$-exchange with virtual $\Delta$-excitation on the
nuclear energy density functional are also investigated. The effective nucleon
mass associated with the kinetic energy density is $\widetilde M^*(\rho_0)=
0.64M$. Furthermore, we find that the isospin properties of nuclear matter get
significantly improved by including the chiral $\pi N\Delta$-dynamics.


title: Single j Shell Observations

abstract:
  In this report we examine topics relating to previous single j shell model
results. A common thread in the two problems is that they both involve the
isospin variable in an important way.


title: Entrance-channel dependence of fission transients

abstract:
  Fission transients describe the fission rate as it evolves towards the
quasistationary value given by Kramers' formula. The nature of fission
transients is dependent on the assumed initial distribution of the compound
nuclei along the fission coordinate. Although the standard initial assumption
of a near-spherical object leads to a transient suppression of the fission rate
(fission delay), a moderate initial fissionlike deformation can reduce the
magnitude of this suppression. For still larger initial deformations, transient
fission enhancements are possible. Examples of this behavior are illustrated
via a one-dimensional Langevin simulation. It is argued that the initial
conditions are determined by the fusion dynamics and thus are entrance-channel
dependent. Transient fission may be considered intermediate between statistical
fission and quasifission as the rapid time scale of transient fission may not
lead to an equilibrium of the angular and mass-asymmetry coordinates. The
relationship between the mean first passage time and the transients are
discussed. For temperatures much smaller than the fission barrier, the mean
first passage time is independent of the nature of the fission transients if
there is no strong competition from evaporation. Thus, fission transients are
most important when the evaporation time scale is smaller than, or of the order
of, the transient time.


title: Comment on "Unmasking the nuclear equation of state"

abstract:
  Referring to a recently published paper [J. Piekarewicz, Phys. Rev. C 69,
041301 (2004)], we point out that Dirac-Brueckner-Hartree-Fock calculations of
the symmetry energy predict values of the neutron skin of heavy nuclei which
are remarkably consistent with those from a recent ``best-fit'' analysis.


title: Pointlike constituent quarks and scattering equivalences

abstract:
  In this paper scattering equivalences are used to simplify current operators
in constituent quark models. The simplicity of the method is illustrated by
applying it to a relativistic constituent quark model that fits the meson mass
spectrum. This model requires a non-trivial constituent quark current operator
to fit the pion form factor data. A model with a different confining
interaction, that has the identical spectrum and can reproduce the measured
pion form factor using only point-like constituent quark impulse currents is
constructed. Both the original and transformed models are relativistic
direct-interaction models with a light-front kinematic subgroup.


title: Soft triaxial roto-vibrational motion in the vicinity of $\gamma=\pi/6$

abstract:
  A solution of the Bohr collective hamiltonian for the $\beta-$soft,
$\gamma-$soft triaxial rotor with $\gamma \sim \pi/6$ is presented making use
of a harmonic potential in $\gamma$ and Coulomb-like and Kratzer-like
potentials in $\beta$. It is shown that, while the $\gamma-$angular part in the
present case gives rise to a straightforward extension of the rigid triaxial
rotor energy in which an additive harmonic term appears, the inclusion of the
$\beta$ part results instead in a non-trivial expression for the spectrum. The
negative anharmonicities of the energy levels with respect to a simple rigid
model are in qualitative agreement with general trends in the experimental
data.


title: Covariant propagator of the Rarita-Schwinger field in the nuclear medium

abstract:
  A formalism for representing the fully relativistic propagator of the
Rarita-Schwinger field in the nuclear medium is developed. Using a convenient
basis for expanding the propagator, or the self energy, it is shown that they
can be represented by 40 energy and momentum dependent quantities which can be
combined into a 2x2 and a 6x6 matrix. In this way calculations reduce to matrix
multiplication. Using the presented formalism the full relativistically
covariant contribution of the pion-nucleon loop to the isobar self energy and
propagator in isospin-symmetric spin-saturated nuclear medium is computed.
Utilizing this propagator the photoabsorption cross-section on in-medium
nucleons in the isobar region is calculated and the result compared with
experimental data.


title: The Single Particle Sum Rules in the Deep-Inelastic Region

abstract:
  We have modelled parton distribution in nuclei using a suitably modified
nuclear Fermi motion. The modifications concern the nucleon rest energy which
changes the Bj\"orken x in nuclear medium. We also introduce final state
interactions between the scattered nucleon and the rest of the nucleus. The
energy-momentum sum rule is saturated. Good agreement with experimental data of
the EMC effect for $x> 0.15$ and nuclear lepton pair production data has been
obtained.


title:
Resonating group method study of kaon-nucleon elastic scattering in the
  chiral SU(3) quark model

abstract:
  The chiral SU(3) quark model is extended to include an antiquark in order to
study the kaon-nucleon system. The model input parameters $b_u$, $m_u$, $m_s$
are taken to be the same as in our previous work which focused on the
nucleon-nucleon and nucleon-hyperon interactions. The mass of the scalar meson
$\sigma$ is chosen to be 675 MeV and the mixing of $\sigma_0$ and $\sigma_8$ is
considered. Using this model the kaon-nucleon $S$ and $P$ partial waves phase
shifts of isospin I=0 and I=1 have been studied by solving a resonating group
method (RGM) equation. The numerical results of $S_{01}$, $S_{11}$, $P_{01}$,
$P_{03}$, and $P_{11}$ partial waves are in good agreement with the
experimental data while the phase shifts of $P_{13}$ partial wave are a little
bit too repulsive when the laboratory momentum of the kaon meson is greater
than 500 MeV in this present calculation.


title: Chiral dynamics of the two Lambda(1405) states

abstract:
  The Lambda(1405) resonance is studied by a chiral unitary approach, in which
the resonance is dynamically generated in coupled-channel meson-baryon
scattering. Investigating the analytic structure of the scattering amplitudes
obtained by the chiral unitary approach, we find two poles around the energies
of the Lambda(1405) coupling differently to the meson-baryon states. We reach
the conclusion that the Lambda(1405) resonance seen in experiments is not just
one single resonance, but a superposition of these two states.


title: Variational Monte Carlo for Microscopic Cluster Models

abstract:
  We examine the application of the Variational Monte Carlo (VMC) method to a
cluster model for halo nuclei. Particular attention is paid to the error
estimate in the presence of correlations in the underlying random walk. We
analyse the required steps for a reliable application of the VMC in the case of
a complicated many-body problem such as the direct solution of the nuclear
hamiltonian with realistic interactions. We also examine the possibility of
variance reduction through the `zero variance principle', paying particular
attention to the complexity of the many-body problem.


title: Cluster models of Lambda-Lambda-6He and Lambda-9Be hypernuclei

abstract:
  Configuration space Faddeev calculations are performed for the binding energy
of Lambda-Lambda-6He and Lambda-9Be bound states, here considered as
alpha-Lambda-Lambda and alpha-alpha-Lambda clusters respectively, in order to
study the dependence of the calculated binding energy on the alpha-Lambda
potential input. For Lambda-Lambda-6He, using realistic interactions, the
uncertainty in extracting the Lambda-Lambda S=L=0 interaction strength does not
exceed 0.1 MeV, which is a fraction of the order of magnitude derived for other
theoretical uncertainties. For Lambda-9Be, the dependence of the calculated
binding energy on the alpha-Lambda potential is considerably larger, of order 1
MeV. Our results for Lambda-9Be suggest that the odd-state alpha-Lambda
interaction is substantially reduced with respect to the even-state component.


title: Models of Meson-Baryon Reactions in the Nucleon Resonance Region

abstract:
  It is shown that most of the models for analyzing meson-baryon reactions in
the nucleon resonance region can be derived from a Hamiltonian formulation of
the problem. An extension of the coupled-channel approach to include $\pi\pi N$
channel is briefly described and some preliminary results for the $N^*(1535)$
excitation are presented.


title: Does \Sigma -\Sigma -\alpha Form a Quasi-Bound State?

abstract:
  We have investigated the possible existence of a quasi-bound state for the
\Sigma -\Sigma -\alpha system in the framework of Faddeev calculations. We are
particularly interested in the state of total iso-spin T=2, since for an inert
\alpha particle there is no strong conversion to \Xi -N-\alpha or \Lambda
-\Lambda -\alpha possible. A \Sigma -\alpha optical potential based on Nijmegen
model D and original \Sigma -\Sigma interactions of the series of Nijmegen
potentials NSC97 as well a simulated Gaussian type versions thereof are used.
Our investigation of the \Sigma -\Sigma -\alpha system leads to a quasi bound
state where, depending on the potential parameters, the energy ranges between
-1.4 and -2.4 MeV and the level width is about 0.2MeV.


title:
Analytical description of classical trajectories and deflection function
  in scattering

abstract:
  Analytical expressions are derived for classical trajectories in repulsive
Coulomb plus multi-step attractive potentials. Thereafter the closed form
expressions are obtained for classical deflection functions. The expressions
are expected to be of use in heavy ion interactions in nuclear physics.


title:
On kaonic deuterium. Quantum field theoretic and relativistic covariant
  approach

abstract:
  We study kaonic deuterium, the bound K^-d state A_(K d). Within a quantum
field theoretic and relativistic covariant approach we derive the energy level
displacement of the ground state of kaonic deuterium in terms of the amplitude
of K^-d scattering for arbitrary relative momenta. Near threshold our formula
reduces to the well-known DGBT formula. The S-wave amplitude of K^-d scattering
near threshold is defined by the resonances Lambda(1405), Sigma(1750) and a
smooth elastic background, and the inelastic channels K^- d -> NY and K^- d ->
NY pion, with Y = Sigma^(+/-), Sigma^0 and Lambda^0, where the final-state
interactions play an important role. The Ericson-Weise formula for the S-wave
scattering length of K^-d scattering is derived. The total width of the energy
level of the ground state of kaonic deuterium is estimated using the
theoretical predictions of the partial widths of the two-body decays A_(Kd) ->
NY and experimental data on the rates of the NY-pair production in the
reactions K^-d -> NY. We obtain Gamma_{1s} = (630 +/-100) eV. For the shift of
the energy level of the ground state of kaonic deuterium we predict
epsilon_(1s) = (353 +/-60)eV.


title:
Convergence of Particle-Hole Expansions for the Description of Nuclear
  Correlations

abstract:
  The convergence properties of a multiparticle-multihole (mp-mh) configuration
mixing approach whose purpose is to describe ground state correlations in
nuclei without particle number and Pauli violations is investigated in the case
of an exactly solvable pairing hamiltonian. Two different truncation schemes
are tested by looking at quantities as correlation energies and single-particle
occupation probabilities. Results show that pairing correlations present in
usual superfluid nuclei can be accurately described using up to 6 particle-6
hole excitations, a convergence fast enought for envisaging extensions to fully
microscopic calculations.


title:
The N(1710)P11 state is confirmed in the re-analysis of the pi N --> K
  Lambda production; it is a good candidate for a non-strange pentaquark

abstract:
  Re-analyzing the old pi N --> K Lambda data, the additional proof is given
for the existence of the N(1710) P11 state, critically needed in light of
reported observations of exotic Theta(1539) and Xi(1862) pentaquarks. An
existing single-resonance model with S11, P11 and P13 Breit-Wiegner resonances
in the s-channel has been applied. It has been shown that the standard set of
resonant parameters fails to reproduce the shape of the differential cross
section. The new resonance parameter determination has been performed keeping
in mind the most recent knowledge about nucleon resonances. The extracted set
of parameters has confirmed the need for the strong contribution of a N(1710)
P11 resonance. The need for any significant contribution of the P13 resonance
has been eliminated. To reproduce the total cross section at the same time with
the linear dependence of the differential cross sections with the cos(theta) in
the energy range 1650 MeV < W < 1800 MeV the P11 resonance can not but be quite
narrow.


title: Partial energies fluctuations and negative heat capacities

abstract:
  We proceed to a critical examination of the method used in nuclear
fragmentation to exhibit signals of negative heat capacity. We show that this
method leads to unsatisfactory results when applied to a simple and well
controlled model. Discrepancies are due to incomplete evaluation of potential
energies.


title: Nucleon resonances and processes involving strange particles

abstract:
  An existing single resonance model with S11, P11 and P13 Breit-Wiegner
resonances in the s-channel has been re-applied to the old pi N --> K Lambda
data. It has been shown that the standard set of resonant parameters fails to
reproduce the shape of the differential cross section. The resonance parameter
determination has been repeated retaining the most recent knowledge about the
nucleon resonances. The extracted set of parameters has confirmed the need for
the strong contribution of a P11(1710) resonance. The need for any significant
contribution of the P13 resonance has been eliminated. Assuming that the Baker.
et al data set\cite{Bak78} is a most reliable one, the P11 resonance can not
but be quite narrow. It emerges as a good candidate for the non-strange counter
partner of the established pentaquark anti-decuplet.


title: Presence of Extra P11 Resonances in Zagreb Analysis Since 1995

abstract:
  The partial wave T-matrices for the pi N, eta N and pi2 N channels have been
obtained within the framework of the coupled channel model using the pi N
elastic and pi N --> eta N data base as input. It has been shown that for the
P11 partial wave an equally good representation of the experimental data
(namely the T(pi N,pi N) and T(pi N,eta N) T-matrices) can be obtained using
either three, or four poles for the Green function propagator. However, the
three Green function pole solution is not acceptable due to the structure of
the extracted resonances. The two out of four P11 resonances, those lying in
the energy range 1700 MeV < MR < 1800 MeV, are poorly determined, but they seem
to be strongly inelastic. The inclusion of other inelastic channels is needed
to determine masses and widths of missing resonances with greater precision.


title: The Gerasimov-Drell-Hearn Sum Rule and the Spin Structure of the Nucleon

abstract:
  The Gerasimov-Drell-Hearn sum rule is one of several dispersive sum rules
that connect the Compton scattering amplitudes to the inclusive photoproduction
cross sections of the target under investigation. Being based on such universal
principles as causality, unitarity, and gauge invariance, these sum rules
provide a unique testing ground to study the internal degrees of freedom that
hold the system together. The present article reviews these sum rules for the
spin-dependent cross sections of the nucleon by presenting an overview of
recent experiments and theoretical approaches. The generalization from real to
virtual photons provides a microscope of variable resolution: At small
virtuality of the photon, the data sample information about the long range
phenomena, which are described by effective degrees of freedom (Goldstone
bosons and collective resonances), whereas the primary degrees of freedom
(quarks and gluons) become visible at the larger virtualities. Through a rich
body of new data and several theoretical developments, a unified picture of
virtual Compton scattering emerges, which ranges from coherent to incoherent
processes, and from the generalized spin polarizabilities on the low-energy
side to higher twist effects in deep inelastic lepton scattering.


title: Thermodynamic analogy for quantum phase transitions at zero temperature

abstract:
  We propose a relationship between thermodynamic phase transitions and
ground-state quantum phase transitions in systems with variable Hamiltonian
parameters. It is based on a link between zeros of the canonical partition
function at complex temperatures and exceptional points of a quantum
Hamiltonian in the complex-extended parameter space. This approach is applied
in the interacting boson model, where it is shown to properly distinguish the
first- and second-order phase transitions.


title:
Determination of the \bar K^0 d scattering length from the reaction pp
  \to d \bar K^0 K^+

abstract:
  The real and imaginary parts of the \bar K^0 d scattering length are
extracted from the \bar K^0 d mass spectrum obtained from the reaction pp \to d
\bar K^0 K^+ measured recently at the Cooler Synchrotron COSY at J\"ulich. We
extract a new limit on the K^- d scattering length, namely Im a \le 1.3 fm and
|Re a| \le 1.3 fm. The limit for the imaginary part of the K^- d scattering
length is supported by data on the total K^- d cross sections.


title: Gamow-Teller GT+ distributions in nuclei with mass A=90-97

abstract:
  We investigate the Gamow-Teller strength distributions in the
electron-capture direction in nuclei having mass A=90-97, assuming a 88Sr core
and using a realistic interaction that reasonably reproduces nuclear
spectroscopy for a wide range of nuclei in the region as well as experimental
data on Gamow-Teller strength distributions. We discuss the systematics of the
distributions and their centroids. We also predict the strength distributions
for several nuclei involving stable isotopes that should be experimentally
accessible for one-particle exchange reactions in the near future.


title:
$\Lambda N$ space-exchange correlation effects in $_\Lambda ^5$He
  hypernucleus

abstract:
  A complete realistic study of $_\Lambda ^5$He hypernucleus is presented using
a realistic Hamiltonian and wave function. This study takes into account all
relevant dynamical correlations along with $\Lambda N$ space-exchange
correlation (SEC). We also compute $\Lambda NN$ force and the corelation
induced by this force. The SEC affects the central repulsive $\lambda N$
correlation significantly at $r \le 2.0$ fm, specially at its peak and in its
vicinity. SEC significantly affects energy breakdown of the hypernucleus,
$\Lambda$-seperation energy, nuclear core (NC) polarization and density
profiles. A lage NC polarization is found with and without SEC, respectively.
The SEC effect is relatively large in two-pion exchange component of $\Lambda
NN$ force. Therefore, any attempt to pin down the strength of this force with
no SEC would be flawed.