title: Further study on 5q configuration states in the chiral SU(3) quark model

abstract:
  The structure of the $5q$ configuration states with strangeness
${\cal{S}}=+1$ is further studied in the chiral SU(3) quark model based on our
previous work. We calculate the energies of fifteen low configurations of the
$5q$ system, four lowest configurations of $J^{\pi}={1/2}^-$ with $4q$
partition $[4]_{orb}(0s^4)[31]^{\sigma f}$, four of $J^{\pi}={1/2}^+$ with $4q$
partition $[31]_{orb}(0s^30p)[4]^{\sigma f}$ and seven of $J^{\pi}={1/2}^+$
with $4q$ partition $[4]_{orb}(0s^30p)[31]^{\sigma f}$. Some modifications are
made in this further study, i.e., the orbital wave function is extended as an
expansion of 4 different size harmonic oscillator forms; three various forms
(quadratic, linear and error function form) of the color confinement potential
are considered; the states with $4q$ partition $[4]_{orb}(0s^30p)[31]^{\sigma
f}$ are added, which are unnegligible in the $J^{\pi}={1/2}^+$ case and were
not considered in our previous paper, further the mixing between configurations
$[31]_{orb}(0s^30p)[4]^{\sigma f}$ and $[4]_{orb}(0s^30p)[31]^{\sigma f}$ is
also investigated. The results show that the T=0 state is still always the
lowest one for both $J^{\pi}={1/2}^-$ and $J^{\pi}={1/2}^+$ states, and
$J^{\pi}={1/2}^-, T=0$ state is always lower than that of $J^{\pi}={1/2}^+$.
All of these modifications can only offer several tens to hundred MeV effect,
and the theoretical value of the lowest state is still about 245 MeV higher
than the experimental mass of $\Theta^+$. It seems to be difficult to get the
calculated mass close to the observed one with the reasonable parameters in the
framework of the chiral SU(3) quark model when the model space is chosen as a
$5q$ cluster.


title: Resonant Fermi gases with a large effective range

abstract:
  We calculate the equation of state of a Fermi gas with resonant interactions
when the effective range is appreciable. Using an effective field theory for
large scattering length and large effective range, we show how calculations in
this regime become tractable. Our results are model-independent, and as an
application, we study the neutron matter equation of state at low densities of
astrophysical interest 0.002 fm^{-3} < rho < 0.02 fm^{-3}, for which the
interparticle separation is comparable to the effective range. We compare our
simple results with those of conventional many-body calculations.


title: Random-phase approximation based on relativistic point-coupling models

abstract:
  The matrix equations of the random-phase approximation (RPA) are derived for
the point-coupling Lagrangian of the relativistic mean-field (RMF) model. Fully
consistent RMF plus (quasiparticle) RPA illustrative calculations of the
isoscalar monopole, isovector dipole and isoscalar quadrupole response of
spherical medium-heavy and heavy nuclei, test the phenomenological effective
interactions of the point-coupling RMF model. A comparison with experiment
shows that the best point-coupling effective interactions accurately reproduce
not only ground-state properties, but also data on excitation energies of giant
resonances.


title:
Centrality dependence of strangeness and (anti)hyperon production at BNL
  RHIC

abstract:
  We evaluate strangeness produced in Au--Au interactions at
  $\sqrt{s_{\rm NN}}=200$ GeV, as function of reaction participant number $A$,
and obtain the relative strange quark content at hadronization. Strange baryon
and antibaryon rapidity density yields are studied, relative to, and as
function of, participant number, and produced hadron yields.


title: Momentum spectra, anisotropic flow, and ideal fluids

abstract:
  If the matter produced in ultrarelativistic heavy-ion collisions reaches
thermal equilibrium, its subsequent evolution follows the laws of ideal fluid
dynamics. We show that general predictions can be made on this basis alone,
irrespective of the details of the hydrodynamical model. We derive several
scaling rules for momentum spectra and anisotropic flow (in particular the
elliptic flow, v2, and the hexadecupole flow, v4) of identified particles.
Comparison with existing data is briefly discussed, and qualitative predictions
are made for LHC.


title:
Neutrino nucleus cross sections for low energy neutrinos at SNS
  facilities

abstract:
  We calculate the neutrino nucleus cross sections for charged lepton
production relevant for the experiments proposed with the stopped muon
neutrinos using neutron spallation source facility. The calculations are done
in local density approximation taking into account Pauli blocking, Fermi motion
effects and renormalization of weak transition strengths in the nuclear medium.
The effect of Coulomb distortion of the lepton produced in charge current
reactions is taken into account by using the Fermi function as well as in a
model where an effective momentum has been used for the lepton moving in the
local Coulomb field of the final nucleus. The numerical results for the
neutrino nucleus total cross sections averaged over Michel spectrum are
presented for various nuclei.


title:
Renormalization of NN Interaction with Chiral Two Pion Exchange
  Potential. Central Phases and the Deuteron

abstract:
  We analyze the renormalization of the NN interaction at low energies and the
deuteron bound state through the Chiral Two Pion Exchange Potential assumed to
be valid from zero to infinity. The short distance Van der Waals singularity
structure of the potential as well as the requirement of orthogonality
conditions on the wave functions determines that, after renormalization, in the
1S0 singlet channel and in the 3S1-3D1 triplet channel one can use the deuteron
binding energy, the asymptotic D/S ratio and the S-wave scattering lengths as
well as the chiral potential parameters as independent variables. We use then
the asymptotic wave function normalization As of the deuteron and the singlet
and triplet effective ranges to determine the chiral constants yielding c1, c3
and c4. The role of finite cut-off corrections, the loss of predictive power
due to uncertainties in the input data and the connection to OPE distorted
waves perturbative approaches is also discussed.


title:
Single $\alpha$-particle orbits and Bose-Einstein condensation in
  $^{12}$C

abstract:
  The $\alpha$-bosonic properties such as single-$\alpha$ orbits and occupation
numbers in $J^\pi$=$0^+$, $2^+$, $1^-$ and $3^-$ states of $^{12}$C around the
$3\alpha$ threshold are investigated with the semi-microscopic $3\alpha$
cluster model. As in other studies, we found that the $0^+_2$ ($2^+_2$) state
has dilute-$3\alpha$-condensate-like structure in which the $\alpha$ particle
is occupied in the single $S$ ($D$) orbit with about 70% (80%) probability. The
radial behaviors of the single-$\alpha$ orbits as well as the occupation
numbers are discussed in detail in comparison with those for the $0^+_1$ and
$2^+_1$ states together with the $1^-_1$ and $3^-_1$ states.


title:
Perfect Fluidity of the Quark Gluon Plasma Core as Seen through its
  Dissipative Hadronic Corona

abstract:
  The agreement of hydrodynamic predictions of differential elliptic flow and
radial flow patterns with Au+Au data is one of the main lines of evidence
suggesting the nearly perfect fluid properties of the strongly coupled Quark
Gluon Plasma, sQGP, produced at RHIC. We study the sensitivity of this
conclusion to different hydrodynamic assumptions on chemical and thermal
freezeout after the sQGP hadronizes. We show that if chemical freezeout occurs
at the hadronization time, the differential elliptic flow for pions increase
with proper time in the late hadronic phase until thermal freezeout and leads
to a discrepancy with the data. In contrast, if both chemical and thermal
equilibrium are maintained past the hadronization, then the mean pT per pion
increases in a way that accidentally preserves v2(pT) from the sQGP phase in
agreement with the data, but at the cost of the agreement with the hadronic
yields. In order that all the data on hadronic ratios, radial flow, and
differential elliptic flow be reproduced, the sQGP must expand with a minimal
viscosity, \eta_Q, that is however even greater than the viscosity, \eta_H, of
its hadronic corona. However, because of the large entropy density difference
of the two phases of QCD matter, the larger viscosity in the sQGP phase leads
to nearly perfect fluid flow while the smaller entropy density of the hadronic
corona strongly hinders the applicability of Euler hydrodynamics. The ``perfect
fluid'' property of the sQGP is thus not due to a sudden reduction of the
viscosity at the critical temperature Tc, but to a sudden increase of the
entropy density of QCD matter and is therefore an important signature of
deconfinement.


title: Wave functions in the f_{7/2} shell, for educational purposes and ideas

abstract:
  We use the spectrum of {42}Sc as input to calculate wave functions and energy
levels of all nuclei in the single-j-shell model with j equal to f_{7/2}. The
value of these results for educational purposes is pointed out. Also new
insights emerge. For example, it is noted that for the (Z=4,N=4) nucleus
{48}Cr, a good quantum number comes out: (-1)^{(v_p+v_n)/2}, where v_p and v_n
are the seniority quantum numbers of the protons and neutrons, respectively.


title: Nuclear halo structure from quasielastic charge-exchange reactions

abstract:
  Neutron and proton densities in the nuclear periphery are investigated within
(p,n) charge-exchange isobar transitions. For this purpose we have developed
parameter-free optical potentials with a detailed treatment of the in-medium
$t_{\tau}$ part of the effective interaction. Non local coupled-channel Lane
equations are solved to obtain the scattering observables. The use of
conventional proton and neutron densities significantly underestimates Fermi
(forward-angle) cross-sections in agreement with findings by various other
groups. However, we have found model-independent densities which provide a
remarkable improvement in the description of the quasielastic scattering
data.The densities obtained are consistent with recent measurements at CERN in
studies of the neutron-to-proton halo factor f(r)=Z$\rho_n/N\rho_p$ with
antiprotons. These findings provide an alternative way to investigate the
nuclear periphery, and may also help to solve the long-standing puzzle of the
underestimated Fermi cross section in (p,n) charge-exchange phenomena.


title:
Effective mass and decay of $\Theta^+$ in nuclear matter in quark-meson
  coupling model

abstract:
  The in-medium mass of a $\thetaplus$, $\mtheta^*$, in cold symmetric nuclear
matter is calculated by using the quark-meson coupling model. The $\Theta^+$ is
treated as an MIT bag with the quark content $uudd\bar s$. Bag parameters for a
free $\thetaplus$ are fixed to reproduce the observed mass of the $\thetaplus$.
In doing so, we use three different values of the $s$-quark mass since the mass
of the $s$-quark is not well known. As usual, the strengths of the $u$ and $d$
quark couplings to $\sigma$- and $\omega$-meson fields are determined to fit
the nuclear saturation properties. However, the coupling constant $g_\sigma^s$
between the $s$-quark and the $\sigma$-meson cannot be fixed from the
saturation properties, and thus we treat $g_\sigma^s$ as a free parameter and
investigate how $\mtheta^*$ depends on $g_\sigma^s$. %$\mtheta^*$ is calculated
up to 2.5 times the nuclear saturation density, %and we find that We find that
$\mtheta^*$ depends significantly on the value of $g_\sigma^s$ but not on the
mass of the $s$-quark. Chemical potentials of the $\Theta^+$ and the $K+N$
system are calculated to discuss the decay of a $\Theta^+$ in nuclear matter.
We calculate the effective mass of a kaon in nuclear matter in two ways; using
the optical potential of $K^-$ in matter and using quark model. By comparing
the effective masses calculated from these two methods, we find the magnitude
of the real part of the optical potential that is consistent with the usual
quark model is about 100 MeV.


title:
Comparative Regge analysis of $\Lambda, \Sigma^0, \Lambda(1520)$ and
  $\Theta^+$ production in $\gamma p$, $\pi p$ and $pp$ reactions

abstract:
  Using the Quark-Gluon Strings Model -- combined with Regge phenomenology --
we perform a comparative analysis of $\Lambda$, $\Sigma^0$, $\Lambda(1520)$ and
$\Theta^+$ production in binary reactions induced by photon, pion and proton
beams on the nucleon. We find that the existing experimental data on the
$\gamma p \to K^+ \Lambda$ differential and total cross sections can be
described very well by the model for photon energies $1 - 16$ GeV and $-t < 2$
GeV$^2$ assuming a dominant contribution of the $K^*$ Regge trajectory.
Moreover, using the same parameters we also reproduce the total $\gamma p \to
K^+ \Sigma^0$ and $\gamma p \to K^+ \Lambda(1520)$ cross sections suggesting a
'universality' of the Regge model. In order to check the consistency of the
approach we evaluate the differential and total cross sections for the reaction
$\pi^- p \to K^0 \Lambda$ which is also found to be dominated by the $K^*$
Regge trajectory. Using the apparent 'universality' of the Regge model we
extend our scheme to the analysis of the binary reactions $\gamma p \to
\bar{K}^0 \Theta^+$, $\pi^- p \to K^- \Theta^+$ and $pp \to \Sigma^+ \Theta^+$
as well as the exclusive and inclusive $\Theta^+$ production in the reactions
$pp \to p \bar{K}^0 \Theta^+$ and $pp \to \Theta^+ X$. Our detailed studies
demonstrate that $\Theta^+$ production does not follow the 'universality'
principle thus suggesting an essentially different internal structure of the
exotic baryon relative to conventional hyperons or hyperon resonances.


title:
Ground-state energies, densities and momentum distributions in
  closed-shell nuclei calculated within a cluster expansion approach and
  realistic interactions

abstract:
  A linked cluster expansion suitable for the treatment of ground-state
properties of complex nuclei, as well as of various particle-nucleus scattering
processes, has been used to calculate the ground-state energy, density and
momentum distribution of 16-O and 40-Ca using realistic interactions. First of
all, a benchmark calculation for the ground-state energy has been performed
using the truncated V8' potential, and consisting in the comparison of our
results with the ones obtained by the Fermi Hypernetted Chain approach,
adopting in both cases the same mean field wave functions and the same
correlation functions. The results exhibited a nice agreement between the two
methods. Therefore, the approach has been applied to the calculation of the
ground-state energy, density and momentum distributions of 16-O and 40-Ca using
the full V8' potential, finding again a satisfactory agreement with the results
based on more advanced approaches where higher order cluster contributions are
taken into account. It appears therefore that the cluster expansion approach
can provide accurate approximations for various diagonal and non diagonal
density matrices, so that it could be used for a reliable evaluation of nuclear
effects in various medium and high energy scattering processes off nuclear
targets. The developed approach can be readily generalized to the treatment of
Glauber type final state interaction effects in inclusive, semi-inclusive and
exclusive processes off nuclei at medium and high energies.


title:
Single particle calculations for a Woods-Saxon potential with triaxial
  deformations, and large Cartesian oscillator basis

abstract:
  We present a computer program which solves the Schrodinger equation of the
stationary states for an average nuclear potential of Woods-Saxon type. In this
work, we take specifically into account triaxial (i.e. ellipsoidal) nuclear
surfaces. The deformation is specified by the usual Bohr parameters. The
calculations are carried out in two stages. In the first, one calculates the
representative matrix of the Hamiltonian in the cartesian oscillator basis. In
the second stage one diagonalizes this matrix with the help of subroutines of
the EISPACK library. If it is wished, one can calculate all eigenvalues, or
only the part of the eigenvalues that are contained in a fixed interval defined
in advance. In this latter case the eigenvectors are given conjointly. The
program is very rapid, and the run-time is mainly used for the diagonalization.
Thus, it is possible to use a significant number of the basis states in order
to insure a best convergence of the results.


title:
Charge and matter distributions and form factors of light, medium and
  heavy neutron-rich nuclei

abstract:
  Results of charge form factors calculations for several unstable neutron-rich
isotopes of light, medium and heavy nuclei (He, Li, Ni, Kr, Sn) are presented
and compared to those of stable isotopes in the same isotopic chain. For the
lighter isotopes (He and Li) the proton and neutron densities are obtained
within a microscopic large-scale shell-model, while for heavier ones Ni, Kr and
Sn the densities are calculated in deformed self-consistent mean-field Skyrme
HF+BCS method. We also compare proton densities to matter densities together
with their rms radii and diffuseness parameter values. Whenever possible
comparison of form factors, densities and rms radii with available experimental
data is also performed. Calculations of form factors are carried out both in
plane wave Born approximation (PWBA) and in distorted wave Born approximation
(DWBA). These form factors are suggested as predictions for the future
experiments on the electron-radioactive beam colliders where the effect of the
neutron halo or skin on the proton distributions in exotic nuclei is planned to
be studied and thereby the various theoretical models of exotic nuclei will be
tested.


title: Charged Lepton Production from Iron Induced by Atmospheric Neutrinos

abstract:
  The charged current lepton production induced by neutrinos in $^{56}Fe$
nuclei has been studied. The calculations have been done for the quasielastic
as well as the inelastic reactions assuming $\Delta$ dominance and take into
account the effect of Pauli blocking, Fermi motion and the renormalization of
weak transition strengths in the nuclear medium. The quasielastic production
cross section for lepton production are found to be strongly reduced due to
nuclear effects while there is about 10% reduction in the inelastic cross
sections in the absence of the final state interactions of the pions. The
numerical results for the momentum and angular distributions of the leptons
averaged over the various atmospheric neutrino spectra at the Soudan and
Gransasso sites have been presented. The effect of nuclear model dependence and
the atmospheric flux dependence on the relative yield of ${\mu}$ to e has been
studied and discussed.


title:
Hadron-string cascade versus hydrodynamics in Cu+Cu collisions at
  $\sqrt{s_{NN}}=200$ GeV

abstract:
  Single particle spectra as well as elliptic flow in Cu+Cu collisions at
$\sqrt{s_{NN}}=200$ GeV are investigated within a hadronic cascade model and an
ideal hydrodynamic model. Pseudorapidity distribution and transverse momentum
spectra for charged hadrons are surprisingly comparable between these two
models. However, a large deviation is predicted for the elliptic flow. The
forthcoming experimental data will clarify the transport and thermalization
aspects of matter produced in Cu+Cu collisions.


title:
Shell-model test of the rotational-model relation between static
  quadrupole moments Q(2^+_1), B(E2)'s, and orbital M1 transitions

abstract:
  In this work, we examine critically the relation between orbital magnetic
dipole (scissors mode) strength and quadrupole deformation properties. Assuming
a simple K=0 ground state band in an even-even nucleus, the quantities Q(2^+_1)
(i.e., the static quadrupole moment) and B(E2)_{0_1 \to 2_1} both are described
by a single parameter--the intrinsic quadrupole moment Q_0. In the shell model,
we can operationally define Q_0(Static) and Q_0(BE2) and see if they are the
same. Following a brief excursion to the sd shell, we perform calculations in
the fp shell. The nuclei we consider ({44,46,48}Ti and {48,50}Cr) are far from
being perfect rotors, but we find that the calculated ratio
Q_0(Static)/Q_0(BE2) is in many cases surprisingly close to one. We also
discuss the collectivity of orbital magnetic dipole transitions. We find that
the large orbital B(M1) strength in {44}Ti relative to {46}Ti and {48}Ti cannot
be explained by simple deformation arguments.


title:
Liquid-gas Phase Transition in Strange Hadronic Matter with Weak Y-Y
  Interaction

abstract:
  The liquid-gas phase transition in strange hadronic matter is reexamined by
using the new parameters about the $\Lambda - \Lambda$ interaction deduced from
recent observation of $^{6}_{\Lambda\Lambda}He$ double hypernucleus. The
extended Furnstahl-Serot-Tang model with nucleons and hyperons is utilized. The
binodal surface, the limit pressure, the entropy, the specific heat capacity
and the Caloric curves are addressed. We find that the liquid-gas phase
transition can occur more easily in strange hadronic matter with weak Y-Y
interaction than that of the strong Y-Y interaction.


title:
Multifragmentation reactions and properties of hot stellar matter at
  subnuclear densities

abstract:
  We point out similarity of thermodynamic conditions reached in intermediate
energy nuclear collisions and in supernova explosions. We show that a
statistical approach, which has been previously applied for nuclear
multifragmentation reactions, can be very useful for description of
electro-neutral stellar matter. Then properties of hot unstable nuclei
extracted from analysis of multifragmentation data can be used for construction
of a realistic equation of state of supernova matter.


title: Relativistic Model of Triquark Structure

abstract:
  At this point it is still unclear whether pentaquarks exist. While they have
be seen in some experiments there are many experiments in which they are not
found. On the assumption that pentaquarks exist, several authors have studied
the properties of pentaquarks. One description considered is that of
pentaquarks which consist of a diquark coupled to a triquark. There is a quite
extensive literature concerning the properties of diquarks and their importance
in the description of the nucleon has been considered by several authors. On
the other hand, there is little work reported concerning the description of
triquarks. In the present work we study a model for the triquark in which it is
composed of a component which contains a quark coupled to a scalar diquark and
another two components in which there is a quark coupled to a kaon. We solve
for the wave function of the triquark and obtain a mass for the triquark of
0.81 GeV which is quite close to the value of 0.80 GeV obtained in a QCD sum
rule study of triquark properties.


title: New broad 8Be nuclear resonances

abstract:
  Energies, total and partial widths, and reduced width amplitudes of 8Be
resonances up to an excitation energy of 26 MeV are extracted from a coupled
channel analysis of experimental data. The presence of an extremely broad J^pi
= 2^+ ``intruder'' resonance is confirmed, while a new 1^+ and very broad 4^+
resonance are discovered. A previously known 22 MeV 2^+ resonance is likely
resolved into two resonances. The experimental J^pi T = 3^(+)? resonance at 22
MeV is determined to be 3^-0, and the experimental 1^-? (at 19 MeV) and 4^-?
resonances to be isospin 0.


title: The importance of strange mesons in neutron star properties

abstract:
  In order to obtain the properties of compact stellar objects, appropriate
equations of state have to be used. In the literature, strange meson fields,
namely the scalar meson field ${\sigma}^*(975)$ and the vector meson field
$\phi(1020)$, had to be considered in order to reproduce the observed strongly
attractive $\Lambda\Lambda$ interaction. The introduction of these strange
mesons makes the equations of state harder (EOS) due to the repulsive effect of
the $\phi(1020)$ meson. In this work the inclusion of these mesons in the
equation of state and their influence on the properties of the neutron stars
are investigated.


title: Low-momentum Hyperon-Nucleon Interactions

abstract:
  We present a first exploratory study for hyperon-nucleon interactions using
renormalization group techniques. The effective two-body low-momentum potential
V_low-k is obtained by integrating out the high-momentum components from
realistic Nijmegen YN potentials. A T-matrix equivalence approach is employed,
so that the low-energy phase shifts are reproduced by V_low-k up to a momentum
scale Lambda ~ 500 MeV. Although the various bare Nijmegen models differ
somewhat from each other, the corresponding V_low-k interactions show
convergence in some channels, suggesting a possible unique YN interaction at
low momenta.


title: Protoneutron stars within the Brueckner-Bethe-Goldstone theory

abstract:
  We study the structure of newly born neutron stars (protoneutron stars)
within the finite temperature Brueckner-Bethe-Goldstone theoretical approach
including also hyperons. We find that for purely nucleonic stars both finite
temperature and neutrino trapping reduce the value of the maximum mass. For
hyperonic stars the effect is reversed, because neutrino trapping shifts the
appearance of hyperons to larger baryon density and stiffens considerably the
equation of state.


title: Extraction of scattering lengths from final-state interactions

abstract:
  A recently proposed method based on dispersion theory, that allows to extract
the scattering length of a hadronic two-body system from corresponding
final-state interactions, is generalized to the situation where the Coulomb
interaction is present. The steps required in a concrete practical application
are discussed in detail. In addition a thorough examination of the accuracy of
the proposed method is presented and a comparison is made with results achieved
with other methods like the Jost-function approach based on the effective-range
approximation. Deficiencies of the latter method are pointed out. The
reliability of the dispersion theory method for extracting also the effective
range is investigated.


title:
Evolving model-free scattering matrix via evolutionary algorithm:
  $^{16}$O-$^{16}$O elastic scattering at 350 MeV

abstract:
  We present a new procedure which enables to extract a scattering matrix
$S(l)$ as a complex function of angular momentum directly from the scattering
data, without any a priori model assumptions implied. The key ingredient of the
procedure is the evolutionary algorithm with diffused mutation which evolves
the population of the scattering matrices, via their smooth deformations, from
the primary arbitrary analytical $S(l)$ shapes to the final ones giving high
quality fits to the data. Due to the automatic monitoring of the scattering
matrix derivatives, the final $S(l)$ shapes are monotonic and do not have any
distortions. For the $^{16}$O-$^{16}$O elastic scattering data at 350 MeV, we
show the independence of the final results of the primary $S(l)$ shapes.
Contrary to the other approaches, our procedure provides an excellent fit by
the $S(l)$ shapes which support the ``rainbow'' interpretation of the data
under analysis.


title:
Bounding the ground-state energy of a many-body system with the
  differential method

abstract:
  This paper promotes the differential method as a new fruitful strategy for
estimating a ground-state energy of a many-body system. The case of an
arbitrary number of attractive Coulombian particles is specifically studied and
we make some favorable comparison of the differential method to the existing
approaches that rely on variational principles. A bird's-eye view of the
treatment of more general interactions is also given.


title: An exactly solvable limit of low energy QCD

abstract:
  Starting from the QCD Hamiltonian, we derive a schematic Hamiltonian for low
energy quark dynamics with quarks restricted to the lowest s-level. The
resulting eigenvalue problem can be solved analytically. Even though the
Hamiltonian exhibits explicit chiral symmetry the severe restriction of the
number of degrees of freedom breaks the pattern of chiral symmetry breaking for
finite quark masses.


title:
Strange-quark contribution to the ratio of neutral- to charged-current
  cross sections in neutrino-nucleus scattering

abstract:
  A formalism based on a relativistic plane wave impulse approximation is
developed to investigate the strange-quark content ($g_{A}^{s}$) of the
axial-vector form factor of the nucleon via neutrino-nucleus scattering.
Nuclear structure effects are incorporated via an accurately calibrated
relativistic mean-field model. The ratio of neutral- to charged-current cross
sections is used to examine the sensitivity of this observable to $g_{A}^{s}$.
For values of the incident neutrino energy in the range proposed by the FINeSSE
collaboration and by adopting a value of $g_{A}^{s}=-0.19$, a 30% enhancement
in the ratio is observed relative to the $g_{A}^{s}=0$ result.


title: Coherent Theta^+ and Lambda(1520) photoproduction off the deuteron

abstract:
  We analyze an effect of the coherent $\Theta^+\Lambda(1520)$ photoproduction
in $\gamma D$ interaction near the threshold. We demonstrate that the coherence
effect becomes manifest in a comparison of the $nK^+$ invariant mass
distribution when the $pK^-$ invariant equals the $\Lambda(1520)$ mass. Our
model calculations indicate a sizeable contribution of resonant and
non-resonant background processes in the $\gamma D\to np K^+K^-$ reaction which
generally exceed the contribution of the coherent resonant channel. However, we
find that the coherent $\Theta^+\Lambda(1520)$ photoproduction is enhanced
relative to the background processes in the forward hemisphere of the $pK^-$
pair photoproduction. Moreover, the coherence effect does not depend on the
$\Theta^+$ photoproduction amplitude and is defined by the probabilities of the
$\Lambda(1520)$ photoproduction and the $\Theta^+\to NK$ transition. Therefore,
this coherence effect may be used as an independent method for studying the
mechanism of $\Theta^+$ production and $\Theta^+$ properties.


title: Suppressed fusion cross section for neutron halo nuclei

abstract:
  Fusion reactions of neutron-halo nuclei are investigated theoretically with a
three-body model. The time-dependent wave-packet method is used to solve the
three-body Schrodinger equation. The halo neutron behaves as a spectator during
the Coulomb dissociation process of the projectile. The fusion cross sections
of 11Be-209Bi and 6He-238U are calculated and are compared with measurements.
Our calculation indicates that the fusion cross section is slightly hindered by
the presence of weakly bound neutrons.


title:
Polarization observables in the semiexclusive photoinduced three-body
  breakup of 3He

abstract:
  The photon and 3He analyzing powers as well as spin correlation coefficients
in the semiexclusive three-body photodisintegration of 3He are investigated for
incoming photon laboratory energies E=12, 40 and 120 MeV. The nuclear states
are obtained by solving three-body Faddeev equations with the AV18
nucleon-nucleon potential alone or supplemented with the UrbanaIX three-nucleon
force. Explicit pi- and rho-meson exchange currents are taken into account, but
we also compare to other models of the electromagnetic current. In some
kinematical conditions we have found strong effects of the three-nucleon force
for the 3He analyzing power and spin correlation coefficients, as well strong
sensitivities to the choice of the currents. This set of predictions should be
a useful guidance for the planning of measurements. In addition, we compare our
results for two-body 3He breakup induced by polarized photons with a few
existing data.


title: Initiative in Nuclear Theory at the Variable Energy Cyclotron Centre

abstract:
  We recall the path breaking contributions of the nuclear theory group of the
Variable Energy Cyclotron Centre, Kolkata. From a beginning of just one person
in 1970s, the group has steadily developed into a leading group in the country
today, with seminal contributions to almost the entire range of nuclear
physics, viz., low energy nuclear reactions, nuclear structure, deep inelastic
collisions, fission, liquid to gas phase transitions, nuclear matter, equation
of state, mass formulae, neutron stars, relativistic heavy ion collisions,
medium modification of hadron properties, quark gluon plasma, and cosmology of
early universe.


title:
Collective excitations in the Unitary Correlation Operator Method and
  relativistic QRPA studies of exotic nuclei

abstract:
  The collective excitation phenomena in atomic nuclei are studied in two
different formulations of the Random Phase Approximation (RPA): (i) RPA based
on correlated realistic nucleon-nucleon interactions constructed within the
Unitary Correlation Operator Method (UCOM), and (ii) relativistic RPA (RRPA)
derived from effective Lagrangians with density-dependent meson-exchange
interactions. The former includes the dominant interaction-induced short-range
central and tensor correlations by means of an unitary transformation. It is
shown that UCOM-RPA correlations induced by collective nuclear vibrations
recover a part of the residual long-range correlations that are not explicitly
included in the UCOM Hartree-Fock ground state. Both RPA models are employed in
studies of the isoscalar monopole resonance (ISGMR) in closed-shell nuclei
across the nuclide chart, with an emphasis on the sensitivity of its properties
on the constraints for the range of the UCOM correlation functions. Within the
Relativistic Quasiparticle RPA (RQRPA) based on Relativistic Hartree-Bogoliubov
model, the occurrence of pronounced low-lying dipole excitations is predicted
in nuclei towards the proton drip-line. From the analysis of the transition
densities and the structure of the RQRPA amplitudes, it is shown that these
states correspond to the proton pygmy dipole resonance.


title:
Microscopic description of elastic and inelastic proton scattering from
  208Pb

abstract:
  Information on the equation of state (EOS) of neutron matter may be gained
from studies of 208Pb. Descriptions of 208Pb require credible models of
structure, taking particular note also of the spectrum. Such may be tested by
analyses of scattering data. Herein, we report on such analyses using an RPA
model for 208Pb in a folding model of the scattering. No a posteriori
adjustment of parameters are needed to obtain excellent agreement with data.
  From those analyses, the skin thickness of 208Pb is constrained to lie in the
range 0.13-0.17 fm.


title: Isospin Transport at Fermi Energies

abstract:
  In this paper we investigate isospin transport mechanisms in semi-peripheral
collisions at Fermi energies. The effects of the formation of a low density
region (neck) between the two reaction partners and of pre-equilibrium emission
on the dynamics of isospin equilibration are carefully analyzed. We clearly
identify two main contributions to the isospin transport: isospin diffusion due
to the $N/Z$ ratio and isospin drift due to the density gradients. Both effects
are sensitive to the symmetry part of the nuclear Equation of State (EOS), in
particular to the value and slope around saturation density.


title: Semiclassical description of shell effects in finite fermion systems

abstract:
  A short survey of the semiclassical periodic orbit theory, initiated by M.
Gutzwiller and generalized by many other authors, is given. Via so-called
semiclassical trace formmulae, gross-shell effects in bound fermion systems can
be interpreted in terms of a few periodic orbits of the corresponding classical
systems. In integrable systems, these are usually the shortest members of the
most degenerate families or orbits, but in some systems also less degenerate
orbits can determine the gross-shell structure. Applications to nuclei, metal
clusters, semiconductor nanostructures, and trapped dilute atom gases are
discussed.


title: Modeling Nuclear Properties with Support Vector Machines

abstract:
  We have made initial studies of the potential of support vector machines
(SVM) for providing statistical models of nuclear systematics with demonstrable
predictive power. Using SVM regression and classification procedures, we have
created global models of atomic masses, beta-decay halflives, and ground-state
spins and parities. These models exhibit performance in both data-fitting and
prediction that is comparable to that of the best global models from nuclear
phenomenology and microscopic theory, as well as the best statistical models
based on multilayer feedforward neural networks.


title: Nucleon-nucleon cross sections in neutron-rich matter

abstract:
  We calculate nucleon-nucleon cross sections in the nuclear medium with
unequal densities of protons and neutrons. We use the
Dirac-Brueckner-Hartree-Fock approach together with realistic nucleon-nucleon
potentials. We examine the effect of neutron/proton asymmetry and find that,
although generally mild, it can be significant in specific regions of the phase
space under consideration.


title: Electroweak quasielastic response functions in nuclear matter

abstract:
  Quasielastic electromagnetic and parity-violating electron scattering
response functions of relativistic nuclear matter are reviewed. The roles
played by the Hartree-Fock field and by nuclear correlations in the Random
Phase Approximation (treated within the continued fraction scheme) are
illustrated. The parity-violating responses of nuclei to polarized electrons
are also revisited, stressing in particular the crucial role played by the pion
in the nuclear dynamics. Finally, some issues surrounding scaling and sum rules
are addressed.


title:
Statistical production of antikaon nuclear bound states in heavy ion
  collisions

abstract:
  Recently it was conjectured that the strongly attractive antikaon--nucleon
potential can result in the formation of antikaon nuclear bound states. We
discuss the formation of such states as possible residues in heavy ion
collisions. In this context, we calculate the excitation functions of single-
and double-$K^-$ clusters in terms of the statistical thermal model. We show
that, if such objects indeed exist, then, in heavy ion collisions, the
single-$K^-$ clusters are most abundantly produced at present SIS energies,
while the double-$K^-$ clusters show a pronounced maximum yield in the energy
domain of the future accelerator at GSI. This is a direct consequence of: i)
the baryonic dominance in low energy heavy ion collisions and the large
baryonic content of the antikaonic bound states; ii) the strong energy
dependence of strangeness production at low energies.
  The production yields of double-strange clusters is compared with that of
double strange baryons. It is shown that at SIS energy there is a linear
scaling relation of the $\Xi^-/K^+$ with $K^+/p$ yields ratio.


title:
Lorentz contraction, geometry and range in antiproton-proton
  annihilation into two pions

abstract:
  We present a geometric interpretation of the so-called annihilation range in
reactions of the type $\bar pp \to$ {\em two light mesons} based upon Lorentz
effects in the highly relativistic final states
($\gamma=E_{\mathrm{cm}}/2mc^2\simeq 6.8-8.0$). Lorentz-boosted meson wave
functions, within the framework of the constituent quark model, result in a
richer angular dependence of the annihilation amplitudes and thus in higher
partial wave contributions ($J>1$) than usually obtained. This approach sheds
some light on what could be a "{\em short}" annihilation range and how it is
influenced by the angular distribution of the final states.


title: Bosonization of the Pairing Hamiltonian

abstract:
  We address the problem of the bosonization of finite fermionic systems with
two different approaches.
  First we work in the path integral formalism, showing how a truly bosonic
effective action can be derived from a generic fermionic one with a quartic
interaction. We then apply our scheme to the pairing hamiltonian in the
degenerate case proving that, in this instance, several of the features
characterizing the spontaneous breaking of the global gauge symmetry U(1)
occurring in the infinite system persist in the finite system as well.
  Accordingly we interpret the excitations associated with the addition and
removal of pairs of fermions as a quasi-Goldstone boson and the excitations
corresponding to the breaking of a pair (seniority one states in the language
of the pairing hamiltonian) as Higgs modes.
  Second, we face the more involved problem of a non-degenerate single particle
spectrum, where one more kind of excitations arises, corresponding to the
promotion of pairs to higher levels. This we do by solving directly the
Richardson equations. From this analysis the existence emerges of critical
values of the coupling constant, which signal the transition between two
regimes, one dominated by the mean field physics, the other by the pairing
interaction.


title: Influence of Chaos on the fusion enhancement by electron screening

abstract:
  We study the effect of screening by bound electrons in low energy nuclear
reactions. We use molecular dynamics to simulate the reactions involving many
electrons: D+$d$, D+D, $^3$He+$d$, $^3$He+D, $^6$Li+$d$, $^6$Li+D, $^7$Li+$p$,
$^7$Li+H. Quantum effects corresponding to the Pauli and Heisenberg principles
are enforced by constraints in terms of the phase space occupancy. In addition
to the well known adiabatic and sudden limits, we propose a new "dissipative
limit" which is expected to be important not only at high energies but in the
extremely low energy region. The dissipative limit is associated with the
chaotic behavior of the electronic motion. It affects also the magnitude of the
enhancement factor. We discuss also numerical experiments using polarized
targets. The derived enhancement factors in our simulation are in agreement
with those extracted within the $R$-matrix approach.


title: Hadronic Matter is Soft

abstract:
  The stiffness of the hadronic equation of state has been extracted from the
production rate of $K^+$ mesons in heavy ion collisions around 1 $A$ GeV
incident energy. The data are best described with a compressibility coefficient
$\kappa$ around 200 MeV, a value which is usually called ``soft''. This is
concluded from a detailed comparison of the results of transport theories with
the experimental data using two different procedures: (i) the energy dependence
of the ratio of $K^+$ from Au+Au and C+C collisions and (ii) the centrality
dependence of the $K^+$ multiplicities. It is demonstrated that input
quantities of these transport theories which are not precisely known, like the
kaon-nucleon potential, the $\Delta N \to N K^+ \Lambda$ cross section or the
life time of the $\Delta$ in matter do not modify this conclusion.


title:
Multiplicity distribution and source deformation in full-overlap U+U
  collisions

abstract:
  We present a full Monte Carlo simulation of the multiplicity and eccentricity
distributions in U+U collisions at sqrt(s) = 200 A GeV. While unavoidable
trigger inefficiencies in selecting full-overlap U+U collisions cause
significant modifications of the multiplicity distribution shown in PRL94,
132301 (2005), a selection of source eccentricities by cutting the multiplicity
distribution is still possible.


title:
Testing of various parametrizations of effective nucleon-nucleon
  interaction in elastic and inelastic scattering of polarized protons from
  $^{12}$C

abstract:
  The parametrization schemes of the effective nucleon-nucleon interaction
proposed by Geramb and by Nakayama and Love are compared in their ability to
reproduce the inelastic scattering observables of polarized protons from
$^{12}$C with the excitation of the $1^+$ level with T=1. The off-shell
behavior of the effective $t$ matrix is shown to be important. Density
dependence of the effective interaction is also analyzed.


title: Dynamics of $K^+$ Production in Heavy Ion Collisions close to Threshold

abstract:
  In this article the production of $K^+$ at energies close to the threshold is
studied in detail. The production mechanisms, the influence of in-medium
effects, cross sections, the nuclear equation of state and the dynamics of the
nucleons on the kaon dynamics are discussed. A special regard will be taken on
the collision of Au+Au at 1.5 GeV, a reaction that has recently been analyzed
in detail by experiments performed by the KaoS and FOPI collaborations at the
SIS accelerator at GSI.


title:
Partial-wave decomposition of the Faddeev amplitude of a
  Poincar\'e-invariant three-fermion bound state

abstract:
  A partial-wave decomposition of the Faddeev amplitude of a Poincare-invariant
three-fermion bound state is presented. Some implications for the properties of
the nucleon as relativistic three-quark bound state are discussed. E.g. it is
demonstrated that the nucleon is not spherically symmetric.


title:
Polishing the Lens: I Pionic Final State Interactions and HBT
  Correlations- Distorted Wave Emission Function (DWEF) Formalism and Examples

abstract:
  The emission of pions produced within a dense, strongly-interacting system of
matter in the presence of strong radial flow and absorption is described using
a relativistic optical model formalism, replacing the attenuated or
unattenuated plane waves of earlier emission function approaches with
``distorted wave'' solutions to a relativistic wave equation including a
complex optical potential. The resulting distorted-wave emission function model
(DWEF) is used in numerical calculations to fit HBT correlations and the
resonance-corrected pion spectrum from central-collision STAR Au+Au pion data
at $\sqrt{s}= 200$ GeV. The parameters of the emission function are constrained
by adopting a pion formation temperature taken from lattice gauge calculations
and a chemical potential equal to the pion mass suggested by chiral symmetry
restoration. Excellent agreement with the STAR data are obtained. The
applications are extended by applying linear participant scaling to the
space-time parameters of the model while keeping all other parameters fixed.
This allows us to predict HBT radii over a range of centralities for both Au+Au
and Cu+Cu collisions. Good agreement is found with STAR HBT data for all but
the most peripheral collisions.


title: Density Dependent Parametrization Models: Formalism and Applications

abstract:
  In this work we derive a formalism to incorporate asymmetry and temperature
effects in the Brown-Rho (BR) scaled lagrangian model in a mean field theory.
The lagrangian density discussed in this work requires less parameters than the
usual models with density dependent couplings. We also present the formalism
with the inclusion of the eight lightest baryons, two lightest leptons, beta
equilibrium and charge neutrality in order to apply the BR scaled model to the
study of neutron stars. The results are again compared with the ones obtained
from another density dependent parametrization model. The role played by the
rearrangement term at T=0 for nuclear or neutron star matter and at finite
temperature is investigated. The BR scaled model is shown to be a good tool in
studies involving density dependent effective masses and in astrophysics
applications.


title: Spectroscopy of Medium to Heavy Single $\Lambda$-Hypernuclei

abstract:
  We develop a method for calculating the doublet splittings of select
ground-state single $\Lambda$-hypernuclei. This hypernuclear spectroscopy is
conducted by supplementing the self-consistent single-particle equations with
an effective interaction, which follows directly from the underlying
lagrangian,to simulate the residual particle-hole interaction. Our previous
investigation, performed using only the leading-order contributions to the
particle-hole interaction, was inadequate. In the present work, this method is
improved upon by increasing the level of truncation in the residual interaction
to include gradient coupling to the neutral vector meson, and thereby
incorporating the tensor force into the calculation (which is known to play a
crucial role in these systems). As a result, we obtain a realistic description
of the effect of the tensor coupling on the doublet orderings and splittings.


title: Neutral and charged pion production in the S-matrix approach

abstract:
  The S-matrix approach is applied to charged and neutral pion production in pp
collisions, in which the spin/isospin channels filter differently the
rescattering mechanism. The chiral perturbation theory rescattering amplitude
is employed. The contributions from the single-nucleon, Z-diagrams and
Delta-isobar mechanisms are also included. For the reactions investigated, the
convergence of the partial wave series is quite satisfactory and J=0 is enough
to describe the data close to threshold.


title: Five-quark components in $\Delta(1232)\to N\pi$ decay

abstract:
  Five-quark $qqqq\bar q$ components in the $\Delta(1232)$ are shown to
contribute significantly to $\Delta(1232)\to N\pi$ decay through
quark-antiquark annihilation transitions. These involve the overlap between the
$qqq$ and $qqqq\bar q$ components and may be triggered by the confining
interaction between the quarks. With a $\sim$ 10% admixture of five-quark
components in the $\Delta(1232)$ the decay width can be larger by factors 2 - 3
over that calculated in the quark model with 3 valence quarks, depending on the
details of the confining interaction. The effect of transitions between the
$qqqq\bar q$ components themselves on the calculated decay width is however
small. The large contribution of the quark-antiquark annihilation transitions
thus may compensate the underprediction of the width of the $\Delta(1232)$ by
the valence quark model, once the $\Delta(1232)$ contains $qqqq\bar q$
components with $\sim$ 10% probability.


title:
Non-locality in the nucleon-nucleon interaction and nuclear matter
  saturation

abstract:
  We study the possible relationship between the saturation properties of
nuclear matter and the inclusion of non-locality in the nucleon-nucleon
interaction. To this purpose we compute the saturation curve of nuclear matter
within the Bethe-Brueckner-Goldstone theory using a recently proposed realistic
non-local potential, and compare it with the corresponding curves obtained with
a purely local realistic interaction (Argonne v$_{18}$) and the most recent
version of the one-boson exchange potential (CD Bonn). We find that the
inclusion of non-locality in the two-nucleon bare interaction strongly affects
saturation, but it is unable to provide a consistent description of few-body
nuclear systems and nuclear matter.


title:
Novel Time-Independent Model for Determining the Critical Mass of a
  Fissile Nuclide

abstract:
  A straightforward, time-independent model for determining the critical mass
of a spherical sample of a fissile nuclide is developed from basic neutron
collision theory and elementary probability arguments. This model is suitable
for presentation to even undergraduate students and gives results in excellent
accord with published values.


title:
The Ideal Liquid Discovered by RHIC, Infrared Slavery Above and Hadronic
  Freedom Below $T_c$

abstract:
  We construct the nature of the matter found in RHIC when its temperature has
dropped down close to, and below, $T_c$. Just above $T_c$ it is composed of
extremely strongly bound quark-antiquark pairs forming chirally restored mesons
of the quantum numbers of the $\pi, S, \rho$ and $a_1$ with very small size and
zero energy and just below $T_c$, it is composed of mesons of the same quantum
numbers with zero mass. We invoke infrared slavery for the former and the
vector manifestation (VM) of hidden local symmetry for the latter. As the
temperature drops below $T_c$, the strongly bound quark-antiquark pairs are
ejected into what is basically a region of "hadronic freedom" in which the
interactions are zero. Experimental evidences for this are seen in the STAR
data.


title:
Improved quark mass density- dependent model with quark and non-linear
  scalar field coupling

abstract:
  The improved quark mass density- dependent model which includes the coupling
between the quarks and a non-linear scalar field is presented. Numerical
analysis of solutions of the model is performed over a wide range of
parameters. The wave functions of ground state and the lowest one-particle
excited states with even and odd parity are given. The root-mean squared
radius, the magnetic moment and the ratio between the axial-vector and the
vector beta-decay coupling constants of the nucleon are calculated. We found
that the present model is successful to describe the properties of nucleon.


title:
Complementary reaction analyses and the isospin mixing of the 4- states
  in 16O

abstract:
  Data from the inelastic scattering of electrons, and of intermediate energy
protons and pions leading to ``stretched'' configuration 4- states near 19 MeV
excitation in 16O as well as from charge exchange (p,n) scattering to an
isobaric analogue (4-) state in 16F have been analyzed to ascertain the degree
of isospin mixing contained within those states and of the amount of
d_{5/2}-p_{3/2}^{-1} particle-hole excitation strength they exhaust. The
electron and proton scattering data have been analyzed using microscopic models
of the structure and reactions, with details constrained by analyses of elastic
scattering data.


title: Relativistic Transport Approach to Collective Nuclear Dynamics

abstract:
  The isoscalar giant monopole resonance (ISGMR) and isovector giant dipole
resonance (IVGDR) in finite nuclei are studied in the framework of a
relativistic transport approach. The kinetic equations are derived within an
effective nucleon-meson field theory in the Relativistic Mean Field (RMF)
scheme, even extended to density dependent vertices. Small amplitude
oscillations are analysed using the Relativistic Vlasov (RV) approach, i.e.
neglecting nucleon collision terms. The time evolution of the isoscalar
monopole moment and isovector dipole moment and the corresponding Fourier power
spectra are discussed. In the case of ^{208}Pb we study in detail the
dependence of the monopole response on the effective mass and symmetry energy
at saturation given by the used covariant effective interaction. We show that a
reduced m^* and a larger a_4 can compensate the effect on the ISGMR energy
centroid of a much larger compressibility modulus K_{nm}. This result is
important in order to overcome the conflicting determination of the nuclear
compressibility between non-relativistic and relativistic effective
interactions. For the symmetry energy dynamical effects, we carefully analyze
the influence of the inclusion of an effective isovector scalar channel,
  \delta-meson field, with constant and density dependent couplings. We show
the relevance of the $slope$ (or pressure) of the symmetry energy at saturation
on the ISGMR and IVGDR modes for neutron-rich systems. Density dependent
vertices are not much affecting our conclusions. Following as a guidance some
extended dispersion relations in nuclear matter, we see two main reasons for
that, the smoothness of the density dependences around saturation and the
presence of compensation effects coming from rearrangement terms.


title:
Imaging Three Dimensional Two-particle Correlations for Heavy-Ion
  Reaction Studies

abstract:
  We report an extension of the source imaging method for analyzing
three-dimensional sources from three-dimensional correlations. Our technique
consists of expanding the correlation data and the underlying source function
in spherical harmonics and inverting the resulting system of one-dimensional
integral equations. With this strategy, we can image the source function
quickly, even with the finely binned data sets common in three-dimensional
analyses.


title: Weak Pion Production From Nuclei

abstract:
  The charged current pion production induced by neutrinos in $^{12}{C}$,
$^{16}{O}$ and $^{56}{Fe}$ nuclei has been studied. The calculations have been
done for the coherent as well as the incoherent processes assuming $\Delta$
dominance and take into account the effect of Pauli blocking, Fermi motion and
the renormalization of $\Delta$ in the nuclear medium. The pion absorption
effects have also been taken into account.


title: Kaon production in heavy ion reactions at intermediate energies

abstract:
  The article reviews the physics related to kaon and antikaon production in
heavy ion reactions at intermediate energies. Chiral dynamics predicts
substantial modifications of the kaon properties in a dense nuclear
environment. The status of the theoretical predictions as well as experimental
evidences for medium effects such as repulsive/attractive mass shifts for
$K^+/K^-$ are reviewed. In the vicinity of the thresholds, and even more
pronounced below threshold, the production of strangeness is a highly
collective process. Starting from elementary reaction channels the
phenomenology of $K^+$ and $K^-$ production, i.e. freeze-out densities, time
scales etc. as derived from experiment and theoretical transport calculations
is presented. Below threshold kaon production shows a high sensitivity on the
nuclear compression reached in heavy ion reactions. This allows to put
constraints on the nuclear equation-of-state which are finally discussed.


title:
Centrality Dependence of Direct Photons in Au+Au Collisions at
  sqrt(s_NN) = 200 GeV

abstract:
  We calculate the spectra of high energy photons emitted in relativistic Au+Au
collisions for various centralities and compare to data recently collected at
the Relativistic Heavy Ion Collider by the PHENIX collaboration. Our results
for photons from primary hard scatterings and photons from interactions of jets
with the medium are consistent with the measurements of neutral pion and direct
photon production in p+p collisions and give a good description of direct
photon spectra measured in Au+Au collisions. The contribution of photons from
jet-to-photon conversion in the medium can be as large as the photon yield from
hard scatterings in the momentum range p_T = 2...6 GeV/c. We show that this
novel mechanism is not ruled out by any existing data.


title:
Influence of Bottom Quark Jet Quenching on Single Electron Tomography of
  Au+Au

abstract:
  High transverse momentum single (non-photonic) electrons are shown to be
sensitive to the stopping power of both bottom, b, and charm, c, quarks in AA
collisions. We apply the DGLV theory of radiative energy loss to predict c and
b quark jet quenching and compare the FONLL and PYTHIA heavy flavor
fragmentation and decay schemes. We show that single electrons in the p_T=5-10
GeV range are dominated by the decay of b quarks rather than the more strongly
quenched c quarks in Au+Au collisions at sqrt{s}=200 AGeV. The {smaller} b
quark energy loss, even for extreme opacities with gluon rapidity densities up
to 3500, is predicted to limit the nuclear modification factor, R_{AA}, of
single electrons to the range R_{AA} ~ 0.5-0.6, in contrast to previous
predictions of R_{AA} ~ 0.2-0.3 based on taking only c quark jet fragmentation
into account.


title:
Comment on the article ``UCN anomalous losses and the UCN capture cross
  section on material defects'' by A. Serebrov et al

abstract:
  We present correct solution of the problem about a scattering of the neutron
on a point-like defect existing in a medium and show that this mechanism cannot
explain anomalous losses of UCN in storage bottles.


title: Interaction of K^- mesons with light nuclei

abstract:
  We calculate the scattering lenths A(K-,3He) and A(K-,4He) using the multiple
scattering approach and different parameters sets for the elementary a(Kbar,N).
Within the zero-range approximation, we find for both systems loosely bound
states with binding energies in the range 2-7 MeV and widths 11-18 MeV. It is
demonstrated that the existence of deeply bound K-,4He states, which have been
predicted in literature, can be tested by measuring the reaction dd -> 4He K-K+
at COSY.


title: Can realistic nuclear interactions tolerate a resonant tetraneutron ?

abstract:
  The possible existence of four-neutron resonances close to the physical
energy region is explored. Faddeev-Yakubovsky equations have been solved in
configuration space using realistic nucleon-nucleon interaction models. Complex
Scaling and Analytical Continuation in the Coupling Constant methods were used
to follow the resonance pole trajectories, which emerge out of artificially
bound tetraneutron states. The final pole positions for four-neutron states lie
in the third energy quadrant with negative real energy parts and should thus
not be physically observable.


title:
Gamma-rigid solution of the Bohr Hamiltonian for gamma = 30 degrees
  compared to the E(5) critical point symmetry

abstract:
  A gamma-rigid solution of the Bohr Hamiltonian for gamma = 30 degrees is
derived, its ground state band being related to the second order Casimir
operator of the Euclidean algebra E(4). Parameter-free (up to overall scale
factors) predictions for spectra and B(E2) transition rates are in close
agreement to the E(5) critical point symmetry, as well as to experimental data
in the Xe region around A=130.


title:
Low-energy etaN interactions: scattering lengths and resonance
  parameters

abstract:
  We consider the impact of two recent pi- p-->eta n measurements on the etaN
scattering length and etaN branching fractions for the N(1535) and N(1520)
resonances within a coupled-channel analysis of piN elastic scattering and etaN
production data. The sensitivity of these results to model input is also
explored.


title: Kaon-nucleon interaction in the extended chiral SU(3) quark model

abstract:
  The chiral SU(3) quark model is extended to include the coupling between the
quark and vector chiral fields. The one-gluon exchange (OGE) which dominantly
governs the short-range quark-quark interaction in the original chiral SU(3)
quark model is now nearly replaced by the vector-meson exchange. Using this
model, the isospin I=0 and I=1 kaon-nucleon S, P, D, F wave phase shifts are
dynamically studied by solving the resonating group method (RGM) equation.
Similar to those given by the original chiral SU(3) quark model, the calculated
results for many partial waves are consistent with the experiment, while there
is no improvement in this new approach for the P_{13} and D_{15} channels, of
which the theoretical phase shifts are too much repulsive and attractive
respectively when the laboratory momentum of the kaon meson is greater than 300
MeV.


title: Effect of nuclear periphery on nucleon transfer in peripheral collisions

abstract:
  A comparison of experimental heavy residue cross sections from the reactions
86Kr+64Ni,112,124Sn with the model of deep-inelastic transfer (DIT) is carried
out. A modified expression for nucleon transfer probabilities is used at
non-overlapping projectile-target configurations, introducing a dependence on
isospin asymmetry at the nuclear periphery. The experimental yields of
neutron-rich nuclei close to the projectile are reproduced better and the trend
deviating from the bulk isospin equilibration is explained. For the
neutron-rich products further from the projectile, originating from hot
quasiprojectiles, the statistical multifragmentation model reproduces the mass
distributions better than the model of sequential binary decay. In the reaction
with proton-rich target 112Sn the nucleon exchange appears to depend on isospin
asymmetry of nuclear periphery only when surface separation is larger than 0.8
fm due to the stronger Coulomb interaction at more compact di-nuclear
configuration.


title: Baseline Cold Matter Effects on J/psi Production in AA Collisions

abstract:
  We present baseline calculations of initial-state shadowing and final-state
absorption effects on J/psi production in nucleus-nucleus collisions at the
Relativistic Heavy Ion Collider. We show predictions for Au+Au and Cu+Cu
collisions at \sqrt{S_{NN}}=200 GeV and Cu+Cu collisions at \sqrt{S_{NN}} = 62
GeV as a function of the rapidity, y, and the number of binary nucleon-nucleon
collisions, N_{\rm coll}.


title:
Exact Analytical Solution of the Constrained Statistical
  Multifragmentation Model and Phase Transitions in Finite Systems

abstract:
  We discuss an exact 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 of this model is done for
finite volumes. It is shown that the real part of any simple pole of the
isobaric partition defines the free energy of the corresponding state, whereas
its imaginary part, depending on the sign, defines the inverse decay/formation
time of this state. The developed formalism allows us, for the first time, to
exactly define the finite volume analogs of gaseous, liquid and mixed phases of
this model from the first principles of statistical mechanics and demonstrate
the pitfalls of earlier works. The finite size effects for large fragments and
the role of metastable (unstable) states are discussed.


title: Interactions of the solar neutrinos with the deuterons

abstract:
  Starting from chiral Lagrangians, possessing the SU(2)_L x SU(2)_R local
chiral symmetry, we derive weak axial one-boson exchange currents in the
leading order in the 1/M expansion (M is the nucleon mass). We apply these
currents in calculations of the cross sections for the disintegration of the
deuterons by the low energy neutrinos. The nuclear wave functions are derived
from a variant of the OBEPQB potential and from the Nijmegen 93 and Nijmegen I
nucleon-nucleon interactions. The comparison of our cross sections with those
obtained within the pionless effective field theory and other potential model
calculations shows that the solar neutrino-deuteron cross sections can be
calculated within an accuracy of 3.3 %.


title:
Electromagnetic response and break-up of light weakly-bound nuclei in a
  dicluster model

abstract:
  The light weakly-bound nucleus $^7$Li is studied within a dicluster
$\alpha+t$ picture. Different observables obtained within our simple model are
compared with previous calculations and experiments showing good agreement. In
particular we calculate dipole and quadrupole electromagnetic response to the
continuum. The energy distribution of B(E$\lambda$) values are consistent with
the energy weighted molecular sum rule and display a sizable contribution of
non-resonant character arising from the weak binding property. The
corresponding form factors for excitations to the continuum are used in a
semiclassical coupled channel scheme to get estimates for the break-up cross
section in a heavy ion reaction. The nuclear contribution is found to play an
important role in the process for bombarding energies around the Coulomb
barrier. The masses and charges ratios of the two clusters are shown to lead to
features of the cluster halo that may significantly differ from the one usually
associated with one-nucleon haloes.


title: Time-Reversal-Violating Schiff Moment of 199Hg

abstract:
  We calculate the Schiff moment of the nucleus 199Hg, created by pi-N-N
vertices that are odd under parity (P) and time-reversal (T). Our approach,
formulated in diagrammatic perturbation theory with important core-polarization
diagrams summed to all orders, gives a close approximation to the expectation
value of the Schiff operator in the odd-A Hartree-Fock-Bogoliubov ground state
generated by a Skyrme interaction and a weak P- and T-odd pion-exchange
potential. To assess the uncertainty in the results, we carry out the
calculation with several Skyrme interactions (the quality of which we test by
checking predictions for the isoscalar-E1 strength distribution in 208Pb) and
estimate most of the important diagrams we omit.


title:
Correlations between $\theta_{13}$ and $\theta_{23}$ in a very long
  baseline neutrino oscillation experiment

abstract:
  A very long baseline experiment, with $L/E$ of $1.6 \times 10^4$ m/MeV, has
been proposed as the ideal means to measure $\theta_{13}$, including its sign,
for neutrino energies less than 50 MeV. Higher energies require consideration
of the earth MSW effect. Approximating a constant density mantle, we examine
the $\nu_e$--$\nu_\mu$ and $\nu_\mu$--$\nu_\mu$ oscillation channels at very
long baselines with particular focus upon the deviation of $\theta_{23}$ from
maximal mixing and the sign of $\theta_{13}$. It is demonstrated that
measurements of these oscillation channels in this region are sensitive to
$\theta_{13}$, including its sign, and to $\theta_{23}$, including its octant,
with a significant correlation between the value of $\theta_{13}$ and the
difference of $\theta_{23}$ from maximal mixing.


title:
Cluster Formation and The Virial Equation of State of Low-Density
  Nuclear Matter

abstract:
  We present the virial equation of state of low-density nuclear matter
composed of neutrons, protons and alpha particles. The virial equation of state
is model-independent, and therefore sets a benchmark for all nuclear equations
of state at low densities. We calculate the second virial coefficients for
nucleon-nucleon, nucleon-alpha and alpha-alpha interactions directly from the
relevant binding energies and scattering phase shifts. The virial approach
systematically takes into account contributions from bound nuclei and the
resonant continuum, and consequently provides a framework to include
strong-interaction corrections to nuclear statistical equilibrium models. The
virial coefficients are used to make model-independent predictions for a
variety of properties of nuclear matter over a range of densities, temperatures
and compositions. Our results provide constraints on the physics of the
neutrinosphere in supernovae. The resulting alpha particle concentration
differs from all equations of state currently used in supernova simulations.
Finally, the virial equation of state greatly improves our conceptual
understanding of low-density nuclear matter.


title: Study of isomers in neutron-rich magic $^{132}$Sn region

abstract:
  Shell model calculations have been done for interpreting two representative
isomeric states in neutron rich $^{132}Sn$ region using SMN and SMPN
Hamiltonians. They are, (i) 2.91 min isomer in $^{138}Cs$ and (ii) the 0.57
$\mu s$ isomer in $^{136}$Sb nuclei. The results are compared with those
obtained with KH5082 and CW5082 Hamiltonians. How the results clearly
distinguish the most appropriate interaction has been discussed.


title: Rescattering in Meson Photoproduction off Few Body Systems

abstract:
  Exclusive reactions induced at high momentum transfer in few body systems
provide us with an original way to study the production and propagation of
hadrons in cold nuclear matter. In very well defined parts of the phase space,
the reaction amplitude develops a logarithmic singularity. It is on solid
ground since it depends only on on-shell elementary amplitudes and on low
momentum components of the nuclear wave function. This is the best window to
study the propagation of exotic configurations of hadrons such as, for
instance, the onset of color transparency. It may appear earlier in meson
photo-production reactions, more particularly in the strange sector, than in
more classical quasi elastic scattering of electrons. More generally, those
reactions provide us with the best tool to determine the cross section of the
scattering of various hadrons (strange particles, vector mesons) from the
nucleon and to access the production of possible exotic states.


title: Symmetric Density Functionals

abstract:
  Variations in distinct restricted spaces of wave functions generate distinct
density functionals. In particular, angular momentum projected Slater
determinants define a new density functional, compatible simultaneously with
angular momentum quantum number and mean field descriptions.


title: Delta-33 medium mass modification and pion spectra

abstract:
  We study the pi+- spectra obtained in 2,4,6,8 A GeV Au-Au collisions within
the thermal model. We find that the main features of the data can be well
described after we include the pions from the decay of the Delta-resonance with
medium mass modification.


title:
The $\beta^4$ potential at the U(5)-O(6) critical point of the
  Interacting Boson Model

abstract:
  Exact numerical results of the interacting boson model Hamiltonian along the
integrable line from U(5) to O(6) are obtained by diagonalization within boson
seniority subspaces. The matrix Hamiltonian reduces to a block tridiagonal form
which can be diagonalized for large number of bosons. We present results for
the low energy spectrum and the transition probabilities for systems up to
10000 bosons, which confirm that at the critical point the system is equally
well described by the Bohr Hamiltonian with a $\beta^4$ potential.


title: Multiplicity fluctuations in the hadron gas with exact conservation laws

abstract:
  The study of fluctuations of particle multiplicities in relativistic
heavy-ion reactions has drawn much attention in recent years, because they have
been proposed as a probe for underlying dynamics and possible formation of
quark-gluon plasma. Thus, it is of uttermost importance to describe the
baseline of statistical fluctuations in the hadron gas phase in a correct way.
We have performed a comprehensive study of multiplicity distributions in the
full ideal hadron-resonance gas in different ensembles, namely grand-canonical,
canonical and microcanonical, using two different methods: asymptotic
expansions and full Monte Carlo simulations. The method based on asymptotic
expansion allows a quick numerical calculation of dispersions in the hadron gas
with three conserved charges at primary hadron level, while the Monte-Carlo
simulation is suitable to study the effect of resonance decays. Even though
mean multiplicities converge to the same values, major differences in
fluctuations for these ensembles persist in the thermodynamic limit, as pointed
out in recent studies. We observe that this difference is ultimately related to
the non-additivity of the variances in the ensembles with exact conservation of
extensive quantities.


title: Evolution of Observables in a Numerical Kinetic Model

abstract:
  The numerical solutions of the nonrelativistic and relativistic Boltzmann
equations have been studied at various initial conditions. Particularly, the
known analytical solution of the nonrelativistic Boltzmann equation at
spherically symmetric Gaussian initial conditions has been recovered and the
corresponding conservation of particle spectra and correlation functions has
been confirmed. Similar conservation properties have been found also for a more
general class of solutions describing the nonrelativistic and relativistic
systems at anisotropic initial conditions.


title:
Polarized Neutron $\beta$-Decay: the Proton Asymmetry and Recoil-Order
  Currents

abstract:
  We present an analytic, recoil-order calculation of the proton asymmetry from
polarized neutron $\beta$-decay. The differential decay rate in terms of
electron energy and proton direction follows, parametrized in terms of the most
general Lorentz-invariant hadron current coupled to a left-handed lepton
current. Implications for experimental efforts to measure recoil-order currents
are discussed.


title: $\Delta\Delta$ dibaryon structure in extended chiral SU(3) quark model

abstract:
  The structure of $\Delta\Delta$ dibaryon is studied in the extended chiral
SU(3) quark model in which vector meson exchanges are included. The effect from
the vector meson fields is very similar to that from the one-gluon exchange
(OGE) interaction. Both in the chiral SU(3) quark model and in the extended
chiral SU(3) quark model, the resultant mass of the $\Delta\Delta$ dibaryon is
lower than the threshold of the $\Delta\Delta$ channel but higher than that of
the $\Delta N\pi$ channel.


title: A Colorful Wake for Gerhard Soff

abstract:
  We calculate the wake induced in a hot QCD plasma by a fast parton in the
framework of linear response theory. We discuss two scenarios: ($i$) a weakly
coupled quark-gluon plasma described by hard-thermal loop perturbation theory
and ($ii$) a strongly coupled quark-gluon plasma which resembles a quantum
liquid. We show that a Mach cone can appear in the second scenario, but not in
the first one


title:
Analyzing eta' photoproduction data on the proton at energies of
  1.5--2.3 GeV

abstract:
  The recent high-precision data for the reaction $\gamma p\to p\eta'$ at
photon energies in the range 1.5--2.3 GeV obtained by the CLAS collaboration at
the Jefferson Laboratory have been analyzed within an extended version of the
photoproduction model developed previously by the authors based on a
relativistic meson-exchange model of hadronic interactions [Phys. Rev. C
\textbf{69}, 065212 (2004)]. The $\eta'$ photoproduction can be described quite
well over the entire energy range of available data by considering $S_{11}$,
$P_{11}$, $P_{13}$, and $D_{13}$ resonances, in addition to the $t$-channel
mesonic currents. The observed angular distribution is due to the interference
between the $t$-channel and the nucleon $s$- and $u$-channel resonance
contributions. The $j=3/2$ resonances are required to reproduce some of the
details of the measured angular distribution. For the resonances considered,
our analysis yields mass values compatible with those advocated by the Particle
Data Group. We emphasize, however, that cross-section data alone are unable to
pin down the resonance parameters and it is shown that the beam and/or target
asymmetries impose more stringent constraints on these parameter values. It is
found that the nucleonic current is relatively small and that the
$NN\eta^\prime$ coupling constant is not expected to be much larger than 2.


title:
Precession Mode on High-K Configurations: Non-Collective
  Axially-Symmetric Limit of Wobbling Motion

abstract:
  We have studied the precession mode, the rotational excitation built on the
high-$K$ isomeric state, in comparison with the recently identified wobbling
mode. The random-phase-approximation (RPA) formalism, which has been developed
for the nuclear wobbling motion, is invoked and the precession phonon is
obtained by the non-collective axially-symmetric limit of the formalism. The
excitation energies and the electromagnetic properties of the precession bands
in $^{178}$W are calculated, and it is found that the results of RPA
calculations well correspond to those of the rotor model; the correspondence
can be understood by an adiabatic approximation to the RPA phonon. As a
by-product, it is also found that the problem of too small out-of-band $B(E2)$
in our previous RPA wobbling calculations can be solved by a suitable choice of
the triaxial deformation which corresponds to the one used in the rotor model.


title: A Comment on Conical Flow Induced by Heavy-Quark Jets

abstract:
  The suppression of high transverse momentum particles, recently discovered at
RHIC, is commonly interpreted as due to parton energy loss. In high energy
nuclear collisions, QCD jets would deposit a large fraction of their energy and
into the produced matter. The question of how this energy is degraded and
whether we can use this phenomenon to probe the properties of the produced
matter is now under active discussion. It has been proposed that if this
matter, which is now being referred to as a {\em strongly coupled Quark-Gluon
Plasma} (sQGP), may behave as a liquid with a very small viscosity.
  In this case, a very specific collective excitation should be produced,
called the ``conical flow'', similar e.g. to the sonic booms generated by the
shock waves produced by supersonic planes. The RHIC experiments seem indeed to
be obtaining some indication that the production of particles emitted opposite
to a high-$p_t$ jet may actually be peaked away from the quenched jet
direction, at an angle roughly consistent with the direction expected in case a
shock wave is produced (i.e. orthogonal to the Mach cone). In this note we
speculate that for tagged heavy-quark jets one may observe a shrinkage of the
Mach cone at moderate $p_t$. The experimental observation of such an effect
would be a very good test for the validity of the whole picture currently
emerging from the study of partonic matter in nuclear collisions.


title:
Dynamic Pairing Effects on Low-Frequency Modes of Excitation in Deformed
  Mg Isotopes close to the Neutron Drip Line

abstract:
  Low-frequency quadrupole vibrations in deformed ${}^{36,38,40}$Mg are studied
by means of the deformed Quasiparticle-RPA based on the coordinate-space
Hartree-Fock-Bogoliubov formalism. Strongly collective $K^{\pi}=0^{+}$ and
$2^{+}$ excitation modes (carrying 10-20 W.u.) are obtained at about 3 MeV. It
is found that dynamical pairing effects play an essential role in generating
these modes. It implies that the lowest $K^{\pi}=0^{+}$ excitation modes are
particularly sensitive indicators of dynamical pairing correlations in deformed
nuclei near the neutron drip line.


title: Neutron-Neutron Fusion

abstract:
  The neutron-neutron fusion process, $nn\to de\nu$, at very low neutron
energies is studied in the framework of pionless effective field theory that
incorporates dibaryon fields. The cross section and electron energy spectrum
for this process are calculated up to next-to-leading order. We include the
radiative corrections of ${\cal O}(\alpha)$ calculated for the one-body
transition amplitude. The precision of our theoretical estimates is found to be
governed essentially by the accuracy with which the empirical values of the
neutron-neutron scattering length and effective range are currently known. Also
discussed is the precision of theoretical estimates of the transition rates of
related electroweak processes in few-nucleon systems.


title: Coupled-cluster calculations for valence systems around O-16

abstract:
  We study the ground and low-lying excited states of O-15, O-17, N-15, and
F-17 using modern two-body nucleon-nucleon interactions and the suitably
designed variants of the ab initio equation-of-motion coupled-cluster theory
aimed at an accurate description of systems with valence particles and holes. A
number of properties of O-15, O-17, N-15, and F-17, including ways the energies
of ground and excited states of valence systems around O-16 change as functions
of the number of nucleons, are correctly reproduced by the equation-of-motion
coupled-cluster calculations. Within a harmonic oscillator basis and large
effective model spaces, our results are converged for the chosen two-body
Hamiltonians. Thus, all disagreements with experiment are, most likely, due to
the degrees of freedom such as three-body interactions not accounted for in our
effective two-body Hamiltonians. In particular, the calculated binding energies
of O-15/N-15 and O-17/F-17 enable us to rationalize the discrepancy between the
experimental and recently published [Phys. Rev. Lett. 94, 212501 (2005)]
equation-of-motion coupled-cluster excitation energies for the Jpi=3- state of
O-16. The results demonstrate the feasibility of the equation-of-motion
coupled-cluster methods to deal with valence systems around closed-shell nuclei
and to provide precise results for systems beyond A=16.


title: Hadrons in Medium

abstract:
  After a short motivation I outline a consistent treatment of hadronic
spectral functions based on transport theory. As examples I discuss nucleon
spectral functions and the observable effects of changes of the properties of
vector mesons inside nuclei.


title: Wavelet Methods in the Relativistic Three-Body Problem

abstract:
  In this paper we discuss the use of wavelet bases to solve the relativistic
three-body problem. Wavelet bases can be used to transform momentum-space
scattering integral equations into an approximate system of linear equations
with a sparse matrix. This has the potential to reduce the size of realistic
three-body calculations with minimal loss of accuracy. The wavelet method leads
to a clean, interaction independent treatment of the scattering singularities
which does not require any subtractions.


title: Density distributions of superheavy nuclei

abstract:
  We employed the Skyrme-Hartree-Fock model to investigate the density
distributions and their dependence on nuclear shapes and isospins in the
superheavy mass region. Different Skyrme forces were used for the calculations
with a special comparison to the experimental data in $^{208}$Pb. The
ground-state deformations, nuclear radii, neutron skin thicknesses and
$\alpha$-decay energies were also calculated. Density distributions were
discussed with the calculations of single-particle wavefunctions and shell
fillings. Calculations show that deformations have considerable effects on the
density distributions, with a detailed discussion on the $^{292}$120 nucleus.
Earlier predictions of remarkably low central density are not supported when
deformation is allowed for.


title:
Nuclear response functions in homogeneous matter with finite range
  effective interactions

abstract:
  The question of nuclear response functions in a homogeneous medium is
examined. A general method for calculating response functions in the random
phase approximation (RPA) with exchange is presented. The method is applicable
for finite-range nuclear interactions. Examples are shown in the case of
symmetric nuclear matter described by a Gogny interaction. It is found that the
convergence of the results with respect to the multipole truncation is quite
fast. Various approximation schemes such as the Landau approximation, or the
Landau approximation for the exchange terms only, are discussed in comparison
with the exact results.


title: Alpha decay half-lives of new superheavy elements

abstract:
  The lifetimes of $\alpha$ decays of the recently produced isotopes of the
elements 112, 114, 116 and the element $^{294}118$ and of some decay products
have been calculated theoretically within the WKB approximation using
microscopic $\alpha$-nucleus interaction potentials. These nuclear potentials
have been obtained by folding the densities of the $\alpha$ and the daughter
nuclei with the M3Y effective interaction, supplemented by a zero-range
pseudo-potential for exchange along with the density dependence. Spherical
charge distributions have been used for calculating the Coulomb interaction
potentials. These calculations provide reasonable estimates for the observed
$\alpha$ decay lifetimes and thus provide reliable predictions for other
superheavies.


title: The Strange Star Surface: A Crust with Nuggets

abstract:
  We reexamine the surface composition of strange stars. Strange quark stars
are hypothetical compact stars which could exist if strange quark matter was
absolutely stable. It is widely accepted that they are characterized by an
enormous density gradient ($~10^{26}$ g/cm$^4$) and large electric fields at
surface. By investigating the possibility of realizing a heterogeneous crust,
comprised of nuggets of strange quark matter embedded in an uniform electron
background, we find that the strange star surface has a much reduced density
gradient and negligible electric field. We comment on how our findings will
impact various proposed observable signatures for strange stars.


title:
Sum rules of single-particle spectral functions in hot asymmetric
  nuclear matter

abstract:
  The neutron and proton single-particle spectral functions in asymmetric
nuclear matter fulfill energy weighted sum rules. The validity of these sum
rules within the self-consistent Green's function approach is investigated. The
various contributions to these sum rules and their convergence as a function of
energy provide information about correlations induced by the realistic
interaction between the nucleons. These features are studied as a function of
the asymmetry of nuclear matter.


title:
Hydrodynamic source with continuous emission in Au+Au collisions at
  $\sqrt{s}=200$ GeV

abstract:
  We analyze single particle momentum spectra and interferometry radii in
central Au+Au collisions at RHIC within a hydro-inspired parametrization
accounting for continuous hadron emission through the whole lifetime of
hydrodynamically expanding fireball. We found that a satisfactory description
of the data is achieved for a physically reasonable set of parameters when the
emission from non space-like sectors of the enclosed freeze-out hypersurface is
fairly long: $ 9$ fm/c. This protracted surface emission is compensated in
outward interferometry radii by positive $r_{out} - t$ correlations that are
the result of an intensive transverse expansion. The main features of the
experimental data are reproduced: in particular, the obtained ratio of the
outward to sideward interferometry radii is less than unity and decreases with
increasing transverse momenta of pion pairs. The extracted value of the
temperature of emission from the surface of hydrodynamic tube approximately
coincides with one found at chemical freeze-out in RHIC Au+Au collisions.
  A significant contribution of the surface emission to the spectra and to the
correlation functions at relatively large transverse momenta should be taken
into account in advanced hydrodynamic models of ultrarelativistic
nucleus-nucleus collisions.


title: Deeply bound meson-nuclear states: concepts and strategies

abstract:
  This presentation reviews recent developments in the understanding of
low-energy pion- and kaon-nucleon interactions as they relate to deeply bound
pionic atoms and possible antikaon-nuclear bound states. A brief update is
given on 1s states of pionic atoms, summarizing their theoretical
interpretation based on in-medium chiral effective field theory. This is
followed by a state-of-the-art discussion of low-energy $\bar{K}N$
interactions, with special emphasis on the subthreshold region relevant to the
proposed kaon-nuclear systems.


title: Charm Production in $\bar pA$-Collisions at the Charmonium Threshhold

abstract:
  We discuss the production of charmonium states in antiproton-nucleus
collisions at the $\psi'$ threshold. It is explained that measurements in $\bar
p A$ collisions will allow to get new information about the strengths of the
inelastic $J/\psi N$ and $\psi'N$ interaction, on the production of $\Lambda_c$
and $\bar{D}$ in charmonium-nucleon interactions and for the first time about
the nondiagonal transitions $\psi' N\to J/\psi N$. The inelastic
$J/\psi$-nucleon cross section is extracted from the comparison of
hadron-nucleus collisions with hadron-nucleon collisions. Predictions for the
ratio of $J/\psi$ to $\psi'$ yields in antiproton-nucleus scatterings close to
the threshold of $\psi'$ production for different nuclear targets are
presented.


title: Few-body physics in effective field theory

abstract:
  Effective Field Theory (EFT) provides a powerful framework that exploits a
separation of scales in physical systems to perform systematically improvable,
model-independent calculations. Particularly interesting are few-body systems
with short-range interactions and large two-body scattering length. Such
systems display remarkable universal features. In systems with more than two
particles, a three-body force with limit cycle behavior is required for
consistent renormalization already at leading order. We will review this EFT
and some of its applications in the physics of cold atoms and nuclear physics.
In particular, we will discuss the possibility of an infrared limit cycle in
QCD. Recent extensions of the EFT approach to the four-body system and N-boson
droplets in two spatial dimensions will also be addressed.


title: Variational Monte Carlo study of pentaquark states

abstract:
  Accurate numerical solution of the five-body Schrodinger equation is effected
via variational Monte Carlo. The spectrum is assumed to exhibit a narrow
resonance with strangeness S=+1. A fully antisymmetrized and pair-correlated
five-quark wave function is obtained for the assumed non-relativistic
Hamiltonian which has spin, isospin, and color dependent pair interactions and
many-body confining terms which are fixed by the non-exotic spectra. Gauge
field dynamics are modeled via flux tube exchange factors. The energy
determined for the ground states with J=1/2 and negative (positive) parity is
2.22 GeV (2.50 GeV). A lower energy negative parity state is consistent with
recent lattice results. The short-range structure of the state is analyzed via
its diquark content.


title: LPM Interference and Cherenkov-like Gluon Bremsstrahlung in Dense Matter

abstract:
  Gluon bremsstrahlung induced by multiple parton scattering in a finite dense
medium has a unique angular distribution with respect to the initial parton
direction. A dead-cone structure with an opening angle $\theta^2_0 \approx
2(1-z)/(zLE)$ for gluons with fractional energy $z$ arises from the
Landau-Pomeranchuck-Migdal (LPM) interference. In a medium where the gluon's
dielectric constant is $\epsilon >1$, the LPM interference pattern is shown to
become Cherenkov-like with an increased opening angle determined by the
dielectric constant $\cos^2\theta_c=z+(1-z)/\epsilon$. For a large dielectric
constant $\epsilon \gg 1+2/z^2LE$, the corresponding total radiative parton
energy loss is about twice that from normal gluon bremsstrahlung. Implications
of this Cherenkov-like gluon bremsstrahlung to the jet correlation pattern in
high-energy heavy-ion collisions is discussed.


title: Cherenkov Radiation from Jets in Heavy-ion Collisions

abstract:
  The possibility of Cherenkov-like gluon bremsstrahlung in dense matter is
studied. We point out that the occurrence of Cherenkov radiation in dense
matter is sensitive to the presence of partonic bound states. This is
illustrated by a calculation of the dispersion relation of a massless particle
in a simple model in which it couples to two different massive resonance
states. We further argue that detailed spectroscopy of jet correlations can
directly probe the index of refraction of this matter, which in turn will
provide information about the mass scale of these partonic bound states.


title: The Virial Equation of State of Low-Density Neutron Matter

abstract:
  We present a model-independent description of low-density neutron matter
based on the virial expansion. The virial equation of state provides a
benchmark for all nuclear equations of state at densities and temperatures
where the interparticle separation is large compared to the thermal wavelength.
We calculate the second virial coefficient directly from the nucleon-nucleon
scattering phase shifts. Our results for the pressure, energy, entropy and the
free energy correctly include the physics of the large neutron-neutron
scattering length. We find that, as in the universal regime, thermodynamic
properties of neutron matter scale over a wide range of temperatures, but with
a significantly reduced interaction coefficient compared to the unitary limit.


title:
Retardation of Particle Evaporation from Excited Nuclear Systems Due to
  Thermal Expansion

abstract:
  Particle evaporation rates from excited nuclear systems at equilibrium matter
density are studied within the Harmonic-Interaction Fermi Gas Model (HIFGM)
combined with Weisskopf's detailed balance approach. It is found that thermal
expansion of a hot nucleus, as described quantitatively by HIFGM, leads to a
significant retardation of particle emission, greatly extending the validity of
Weisskopf's approach. The decay of such highly excited nuclei is strongly
influenced by surface instabilities.


title: Quenching of pairing gap at finite temperature in 184W

abstract:
  We extract pairing gap in $^{184}$W at finite temperature for the first time
from the experimental level densities of $^{183}$W, $^{184}$W, and $^{185}$W
using "thermal" odd-even mass difference. We found the quenching of pairing gap
near the critical temperature $T_c = 0.47$ MeV in the BCS calculations. It is
shown that the monopole pairing model with a deformed Woods-Saxon potential
explains the reduction of the pairing correlation using the partition function
with the number parity projection in the static path approximation plus
random-phase approximation.


title: Anisotropic flow in Cu+Au collisions at $\sqrt{s_{NN}}=200$ GeV

abstract:
  The anisotropic flow of charged hadrons in asymmetric Cu+Au collisions at the
Relativistic Heavy Ion Collider is studied in a multi-phase transport model.
Compared with previous results for symmetric Au+Au collisions, charged hadrons
produced around midrapidity in asymmetric collisions are found to have a
stronger directed flow $v_{1}$ and their elliptic flow $% v_{2} $ is also more
sensitive to the parton scattering cross section. While higher-order flows
$v_{3}$ and $v_{4}$ are small at all rapidities, both $% v_{1}$ and $v_{2}$ in
these collisions are appreciable and show an asymmetry in forward and backward
rapidities.


title:
Probing the density dependence of the symmetry potential in intermediate
  energy heavy ion collisions

abstract:
  Based on the ultrarelativistic quantum molecular dynamics (UrQMD) model, the
effects of the density-dependent symmetry potential for baryons and of the
Coulomb potential for produced mesons are investigated for neutron-rich heavy
ion collisions at intermediate energies. The calculated results of the
$\Delta^-/\Delta^{++}$ and $\pi ^{-}/\pi ^{+}$ production ratios show a clear
beam-energy dependence on the density-dependent symmetry potential, which is
stronger for the $\pi ^{-}/\pi ^{+}$ ratio close to the pion production
threshold. The Coulomb potential of the mesons changes the transverse momentum
distribution of the $\pi ^{-}/\pi ^{+}$ ratio significantly, though it alters
only slightly the $\pi^-$ and $\pi^+$ total yields. The $\pi^-$ yields,
especially at midrapidity or at low transverse momenta and the $\pi^-/\pi^+$
ratios at low transverse momenta, are shown to be sensitive probes of the
density-dependent symmetry potential in dense nuclear matter. The effect of the
density-dependent symmetry potential on the production of both, K$^0$ and K$^+$
mesons, is also investigated.