The quasielastic (QE) contribution of the nuclear inclusive electron scattering model developed by Gil, Nieves, and Oset [Nucl. Phys. A627, 543 (1997); A627, 599 (1997)] is extended to the study of electroweak charged current (CC) induced nuclear reactions, at intermediate energies of interest for future neutrino oscillation experiments. The model accounts for, among other nuclear effects, long range nuclear [random phase approximation (RPA)] correlations, final state interaction (FSI), and Coulomb corrections. Predictions for the inclusive muon capture in ${}^{12}\mathrm{C}$ and the reaction ${}^{12}\mathrm{C}$ $({\nu }_{\mu },{\mu }^{-})X$ near threshold are also given. RPA correlations are shown to play a crucial role and their inclusion leads to one of the best existing simultaneous description of both processes, with accuracies of the order of 10–15 % for the muon capture rate and even better for the Liquid Scintillating Neutrino Detector (LSND) measurement.

We study the predictive power of Skyrme forces with respect to low lying quadrupole spectra along the chains of Sn, Cd, and Te isotopes. Excitation energies and $B\left(E2\right)$ values for the lowest quadrupole states are computed from a collective Schrödinger equation which is deduced through a collective path generated by constraint Skyrme-Hartree-Fock (SHF) plus self-consistent cranking for the dynamical response. We compare the results from four different Skyrme forces, all treated with two different pairing forces (volume versus density-dependent pairing). The region around the neutron shell closure $N=82$ is very sensitive to changes in the Skyrme while the midshell isotopes in the region $N<82$ depend mainly on the adjustment of pairing. The neutron rich isotopes are most sensitive and depend on both aspects.

We present our results on properties of ground states for nucleonic systems in the presence of random two-body interactions. In particular, we calculate probability distributions for parity, seniority, spectroscopic (i.e., in the laboratory frame) quadrupole moments, and discuss $\alpha$ clustering in the ground states. We find that the probability distribution for the parity of the ground states obtained by a two-body random ensemble simulates that of realistic nuclei with $A⩾70$: positive parity is dominant in the ground states of even-even nuclei, while for odd-odd nuclei and odd-mass nuclei we obtain with almost equal probability ground states with positive and negative parity. In addition, assuming pure random interactions, we find that, for the ground states, low seniority is not favored, no dominance of positive values of spectroscopic quadrupole deformation is observed, and there is no sign of $\alpha$-clustering correlation, all in sharp contrast to realistic nuclei. Considering a mixture of a random and a realistic interaction, we observe a second-order phase transition for the $\alpha$-clustering correlation probability.

High-spin states in ${}^{43}\mathrm{Sc}$ have been investigated by using the in-beam $\gamma$-ray technique with the ${}^{27}\mathrm{Al}\left({}^{19}\mathrm{F},p2n\right)$ reaction at $50\mathrm{MeV}$. The $J^{\pi }=(17∕2^{-})$ level at $4382\mathrm{keV}$, the $J^{\pi }=(17∕2^{-},21∕2^{-})$ level at $4633\mathrm{keV}$, and some higher-lying levels were newly identified above the $J^{\pi }=19∕2^{-}$ high-spin isomer, while the quasirotational structure built on the $J^{\pi }=3∕2^{+}$ state has been extended up to the terminating $J^{\pi }=(27∕2^{+})$ state. The energy levels of the observed positive-parity quasirotational band were consistent with the prediction of the shell-model calculation in $\{0d_{3∕2},0f_{7∕2},1p_{3∕2}\}$ model space, while the $J^{\pi }=(17∕2^{-},21∕2^{-})$ level at $4633\mathrm{keV}$ could not be reproduced by the calculation in $\left\{0f1p\right\}$ model space.

Differential neutron elastic scattering cross sections for ${}^{12}\mathrm{C}$, ${}^{40}\mathrm{Ca}$, and ${}^{208}\mathrm{Pb}$ have been measured using the continuum neutron source at the Los Alamos Neutron Science Center. The mean incident neutron kinetic energies ranged from $65\text{to}225\mathrm{MeV}$. The large acceptance drift chamber based $(n,p)$ recoil detector telescope spanned a center-of-mass angular range of 7° to 23°. The measured cross sections are compared with calculations obtained with different optical model potentials, including predictions based on microscopic theory and phenomenology.

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

We present results on charged particle production at very low transverse momenta in the 15% most central $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrt{s_{NN}}=200\mathrm{GeV}$ obtained with the PHOBOS detector at the Relativistic Heavy Ion Collider. The invariant yields were measured at midrapidity in the transverse momentum ranges from $30\text{to}50\mathrm{MeV}∕c$ for charged pions, $90\text{to}130\mathrm{MeV}∕c$ for charged kaons and $140\text{to}210\mathrm{MeV}∕c$ for protons and antiprotons. No significant enhancement in low transverse momentum particle production is observed as compared to extrapolations of identified particle spectra measured at an intermediate $p_T$ range. The spectra tend to flatten at low $p_T$, consistent with the expectations of transverse expansion of the system.

The reaction cross section $\left({\sigma }_R\right)$ for the neutron-rich nucleus ${}^{17}\mathrm{B}$ on a carbon target has been measured at an energy of $77A\mathrm{MeV}$ by the transmission method. An enhancement of ${\sigma }_R$ at intermediate energy compared to that at high energy was observed. The density distribution of ${}^{17}\mathrm{B}$ was deduced through the energy dependence of ${\sigma }_R$ using a finite-range Glauber-type calculation under an optical-limit approximation as well as a few-body approach. The existence of a long neutron tail in ${}^{17}\mathrm{B}$ was demonstrated. The fraction of the wave function with the valence two-neutron configuration of ${\left(2s_{1∕2}\right)}_{J=0}^2$ or ${\left(1d_{5∕2}\right)}_{J=0}^2$ was found to be $50\pm 10\%$ based on a finite-range few-body Glauber-type calculation.

The contribution of rescattering to final state interactions in $(e,e^{\prime }p)$ cross sections is studied for medium and high missing energies using a semiclassical model. This approach considers two-step processes that lead to the emission of both nucleons. The effects of nuclear transparency are accounted for in a Glauber-inspired approach and the dispersion effects of the medium at low energies are included. It is found that rescattering is strongly reduced in parallel kinematics. At high missing energies and momenta, the distortion of the short-range correlated tail of the spectral function is dominated by a rearrangement of that strength itself. In perpendicular kinematics, a further enhancement of the experimental yield is due to strength that is originally in the mean field region. This contribution becomes negligible at large missing momenta.

The light scalar meson spectrum is studied using the improved ladder QCD with the $U_A\left(1\right)$ breaking Kobayashi-Maskawa-’t Hooft interaction by solving the Schwinger-Dyson and Bethe-Salpeter equations. The dynamically generated momentum-dependent quark mass is large enough in the low momentum region to give rise to the spontaneous breaking of chiral symmetry. Due to the large dynamical quark mass, the scalar mesons become the $q\overline{q}$ bound states. Since the parameters have been all fixed to reproduce the light pseudoscalar meson masses and the decay constant, there is no free parameter in the calculation of the scalar mesons. We obtain $M_{\sigma }=667\mathrm{MeV}$, $M_{a_0}=942\mathrm{MeV}$, and $M_{f_0}=1336\mathrm{MeV}$. They are in good agreement with the observed masses of $\sigma \left(600\right)$, $a_0\left(980\right)$, and $f_0\left(1370\right)$, respectively. We therefore conclude that these states are the members of the light scalar meson nonet. The mass of $K_0^{*}$ is obtained between that of $a_0$ and $f_0$ and the corresponding state is not observed experimentally. We also find that the strangeness content in the $\sigma$ meson is about 5%.

We have reinvestigated the structure of the ${}^{107}\mathrm{Tc}$ nucleus reported in other works. Excited states in ${}^{107}\mathrm{Tc}$, populated in spontaneous fission of ${}^{248}\mathrm{Cm}$, were studied by means of prompt-$\gamma$ spectroscopy, using the EUROGAM2 multidetector array. Parity assignments to the 45.6 and 65.6 keV levels were changed, based on conversion coefficient measurements. A new band found on top of the 45.6 keV level corresponds to the $\pi 5∕2^{-}\left[303\right]$ configuration. The positive-parity, yrast band in ${}^{107}\mathrm{Tc}$ is built on top of the 65.6 keV level and corresponds to the $\pi 5∕2^{+}\left[422\right]$ configuration. The configurations observed in ${}^{107}\mathrm{Tc}$ agree well with the scheme of single-proton excitations calculated for this nucleus.

The isotopes ${}^{54}\mathrm{Ni}$, ${}^{56}\mathrm{Ni}$, and ${}^{58}\mathrm{Ni}$ have been studied via intermediate-energy Coulomb excitation at the National Superconducting Cyclotron Laboratory. Absolute $B(E2;0_1^{+}\to 2_1^{+})$ excitation strengths have been determined for all three nuclei using a consistent experimental approach, and a measure of quadrupole collectivity has been established in the vicinity of the much discussed doubly magic shell closure at $N=Z=28$. The energy of and excitation strength to the first $2^{+}$ state of ${}^{54}\mathrm{Ni}$ have been observed for the first time. The results are compared to large-scale shell-model calculations that predict that the $E2$ strength in ${}^{54}\mathrm{Ni}$ should be divided between the first and second $2^{+}$ states.

Transverse energy $\left(E_T\right)$ distributions have been measured for $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrt{s_{NN}}=200\mathrm{GeV}$ by the STAR Collaboration at RHIC. $E_T$ is constructed from its hadronic and electromagnetic components, which have been measured separately. $E_T$ production for the most central collisions is well described by several theoretical models whose common feature is large energy density achieved early in the fireball evolution. The magnitude and centrality dependence of $E_T$ per charged particle agrees well with measurements at lower collision energy, indicating that the growth in $E_T$ for larger collision energy results from the growth in particle production. The electromagnetic fraction of the total $E_T$ is consistent with a final state dominated by mesons and independent of centrality.

We discuss recently measured event-by-event fluctuations of transverse momentum and of multiplicity in relativistic heavy-ion collisions. It is shown that the nonmonotonic behavior of the $p_T$ fluctuations as a function of collision centrality can be fully explained by the observed nonmonotonic multiplicity fluctuations. A possible mechanism responsible for the multiplicity fluctuations is also considered.

Effective Lagrangian models of charmonium have recently been used to estimate dissociation cross sections with light hadrons. Detailed study of the symmetry properties reveals possible shortcomings relative to chiral symmetry. We therefore propose a new Lagrangian and point out distinguishing features amongst the different approaches. Moreover, we test the models against Adler’s theorem, which requires, in the appropriate limit, the decoupling of pions from the theory for the normal parity sector. Using the newly proposed Lagrangian, which exhibits ${\mathrm{SU}}_L\left(N_f\right)\times {\mathrm{SU}}_R\left(N_f\right)$ symmetry and complies with Adler’s theorem, we find dissociation cross sections with pions that are reduced in an energy-dependent way, with respect to cases where the theorem is not fulfilled.

We apply the chiral SU(3) quark mean field model to study the properties of strange hadronic matter at finite temperature. The liquid-gas phase transition is studied as a function of the strangeness fraction. The pressure of the system cannot remain constant during the phase transition, since there are two independent conserved charges (baryon and strangeness number). In a range of temperatures around $15\mathrm{MeV}$ (precise values depending on the model used) the equation of state exhibits multiple bifurcates. The difference in the strangeness fraction $f_s$ between the liquid and gas phases is small when they coexist. The critical temperature of strange matter turns out to be a nontrivial function of the strangeness fraction.

In a new application of the algebraic interacting vector boson model (IVBM), we exploit the reduction of its $Sp(12,R)$ dynamical symmetry group to $Sp(4,R)\otimes SO\left(3\right)$, which defines basis states with fixed values of the angular momentum $L$. The relationship of the latter to $U\left(6\right)\subset U\left(3\right)\otimes U\left(2\right)$, which is the rotational limit of the model, means the energy distribution of collective states with fixed angular momentum can be studied. Results for low-lying spectra of rare-earth nuclei show that the energies of collective positive parity states with $L=0,2,4,6\dots$ lie on second-order curves with respect to the number of collective phonons $n$ or vector bosons $N=4n$ out of which the states are built. The analysis of this behavior leads to insight regarding the common nature of collective states, tracking vibrational as well as rotational features.

Microsecond isomers in the In and Cd isotopes, in the mass range $A=123\text{to}130$, were investigated at the ILL reactor, Grenoble, using the LOHENGRIN mass spectrometer, through thermal-neutron induced fission reactions of Pu targets. The level schemes of the odd-mass ${}^{123–129}\mathrm{In}$ and new measurements of the $\mu \mathrm{s}$ half-lives of the odd-odd ${}^{126–130}\mathrm{In}$ are reported. However, the expected $8^{+}$ isomers in the even-mass Cd isotopes were not observed. The comparisons between the experimental $B\left(M2\right)$ strengths for In and Sn isotopes are discussed. A shell-model study of the heaviest In and Cd nuclei was performed using a realistic interaction derived from the CD-Bonn nucleon-nucleon potential. The calculation predicts values of the half-lives of the first $8^{+}$ states in ${}^{126,128}\mathrm{Cd}$ of $\sim 10\mathrm{ns}$, which could explain the nonobservation of $\mu \mathrm{s}$ isomers. Comparison shows that the calculated levels of ${}^{130}\mathrm{In}$ and ${}^{129}\mathrm{In}$ are in good agreement with the experimental values while some discrepancies occur for the lighter In isotopes. The collectivity of ${}^{126,128}\mathrm{Cd}$ is discussed in the framework of the shell model and in comparison with ${}^{204}\mathrm{Hg}$.

Level densities and radiative strength functions in ${}^{171}\mathrm{Yb}$ and ${}^{170}\mathrm{Yb}$ nuclei have been measured using the ${}^{171}\mathrm{Yb}({}^3\mathrm{He},{}^3\mathrm{He}^{\prime }\gamma ){}^{171}\mathrm{Yb}$ and ${}^{171}\mathrm{Yb}({}^3\mathrm{He},\alpha \gamma ){}^{170}\mathrm{Yb}$ reactions. New data on ${}^{171}\mathrm{Yb}$ are compared to previous measurements for ${}^{171}\mathrm{Yb}$ from the ${}^{172}\mathrm{Yb}({}^3\mathrm{He},\alpha \gamma ){}^{171}\mathrm{Yb}$ reaction. The systematics of level densities and radiative strength functions in ${}^{170,171,172}\mathrm{Yb}$ are established. The entropy excess in ${}^{171}\mathrm{Yb}$ relative to the even-even nuclei ${}^{170,172}\mathrm{Yb}$ due to the unpaired neutron quasiparticle is found to be approximately $2k_B$. Results for the radiative strength function from the two reactions lead to consistent parameters characterizing the “pygmy” resonances. Pygmy resonances in the ${}^{170,172}\mathrm{Yb}$ populated by the $({}^3\mathrm{He},\alpha )$ reaction appear to be split into two components for both of which a complete set of resonance parameters is obtained.

The rapidity distribution of gluons produced in heavy ion collisions is studied by a numerical computation in $(2+1)$-dimensional classical Yang-Mills theory. By assuming that the classical source strength $g^2\mu$ depends on rapidity as $g^4{\mu }^2\sim e^{\pm \lambda y}$ and studying collisions of two nuclei with different $g^2\mu$, we find that the rapidity distribution of produced gluons at central rapidities is very broad. The transverse energy is seen to decrease even more slowly as a function of $y$ than the multiplicity. We discuss these results and the range in $y$ and $\sqrt{s}$ where they are applicable in the light of experimental results and other theoretical calculations.