Hauser-Feshbach calculations are frequently done in deformed nuclei. Although modifications are made in the level density to reflect the rotational bands for deformed nuclei, these calculations are in error if a conventional Hauser-Feshbach code is used. A modification to the Hauser-Feshbach formalism is proposed. The new version of the formalism was tried, both with $K$ conserved and $K$ mixed. It is found that even in the limit of $K$ mixing the results do not agree completely with the calculations using a spherical (conventional) Hauser-Feshbach code with the same input. A formula frequently used to calculate the $J$ dependence of level densities in deformed nuclei is found to be in error.

The transverse momentum ($p_T$) spectra and ratios of identified charged hadrons (${\pi }^{\pm }$, $K^{\pm }$, $p$, $\overline{p}$) produced in $\sqrt{s_{{}_{NN}}}=200$ GeV $\mathrm{Au}+\mathrm{Au}$ and $d+\text{Au}$ collisions are reported in five different centrality classes for each collision species. The measurements of pions and protons are reported up to $p_T=6$ GeV/$c$ (5 GeV/$c$), and the measurements of kaons are reported up to $p_T=4$ GeV/$c$ (3.5 GeV/$c$) in $\mathrm{Au}+\mathrm{Au}$ ($d+\text{Au}$) collisions. In the intermediate $p_T$ region, between 2 and 5 GeV/$c$, a significant enhancement of baryon-to-meson ratios compared to those measured in $p+p$ collisions is observed. This enhancement is present in both $\mathrm{Au}+\mathrm{Au}$ and $d+\text{Au}$ collisions and increases as the collisions become more central. We compare a class of peripheral $\mathrm{Au}+\mathrm{Au}$ collisions with a class of central $d+\text{Au}$ collisions which have a comparable number of participating nucleons and binary nucleon-nucleon collisions. The $p_T$-dependent particle ratios for these classes display a remarkable similarity, which is then discussed.

The surface tension of quark matter plays a crucial role for the possibility of quark matter nucleation during the formation of compact stellar objects and also for the existence of a mixed phase within hybrid stars. However, despite its importance, this quantity does not have a well-established numerical value. Some early estimates have predicted that, at zero temperature, the value falls within the wide range ${\gamma }_0\approx 10$–300 MeV/fm${}^2$ but, very recently, different model applications have reduced these numerical values to fall within the range ${\gamma }_0\approx 5$–30 MeV/fm${}^2$, which would favor the phase conversion process as well as the appearance of a mixed phase in hybrid stars. In magnetars one should also account for the presence of very high magnetic fields which may reach up to about $eB\approx 3$–30 $m_{\pi }^2$ ($B\approx {10}^{19}$–10${}^{20}$ $G$) at the core of the star so it may also be important to analyze how the presence of a magnetic field affects the surface tension. With this aim we here consider magnetized two-flavor quark matter, described by the Nambu–Jona-Lasinio model. We show that although the surface tension oscillates around its $B=0$ value, when $0<eB\lesssim 10m_{\pi }^2$, it only reaches values which are still relatively small. For $eB\approx 5.5m_{\pi }^2$ the $B=0$ surface tension value drops by about $30\%$ while for $eB\gtrsim 10m_{\pi }^2$ it quickly raises with the field intensity so the phase conversion and the presence of a mixed phase should be suppressed if extremely high fields are present. We also investigate how thermal effects influence the surface tension for magnetized quark matter.

We study linear and nonlinear wave propagation in a dense and cold hadron gas and also in a cold quark-gluon plasma, taking viscosity into account and using the Navier-Stokes equation. The equation of state of the hadronic phase is derived from the nonlinear Walecka model in the mean-field approximation. The quark-gluon plasma phase is described by the MIT equation of state. We show that in a hadron gas viscosity strongly damps wave propagation and also hinders shock-wave formation. This marked difference between the two phases may have phenomenological consequences and lead to new quark-gluon plasma signatures.

The scattering lengths and effective ranges that describe low-energy nucleon-nucleon scattering are calculated in the limit of SU(3)-flavor symmetry at the physical strange-quark mass with lattice quantum chromodynamics. The calculations are performed with an isotropic clover discretization of the quark action in three volumes with spatial extents of $L\sim 3.4\mathrm{fm}$, $4.5\mathrm{fm}$, and $6.7\mathrm{fm}$, and with a lattice spacing of $b\sim 0.145\mathrm{fm}$. With determinations of the energies of the two-nucleon systems (both of which contain bound states at these up and down quark masses) at rest and moving in the lattice volume, Lüscher's method is used to determine the low-energy phase shifts in each channel, from which the scattering length and effective range are obtained. The scattering parameters, in the ${}^1{S}_0$ channel are found to be $m_{\pi }{a}^{{(}^1{S}_0)}=9.{50}_{-0.69}^{+0.78}{}_{-0.80}^{+1.10}$ and $m_{\pi }{r}^{{(}^1{S}_0)}=4.{61}_{-0.31}^{+0.29}{}_{-0.26}^{+0.24}$, and in the ${}^3{S}_1$ channel are $m_{\pi }{a}^{{(}^3{S}_1)}=7.{45}_{-0.53}^{+0.57}{}_{-0.49}^{+0.71}$ and $m_{\pi }{r}^{{(}^3{S}_1)}=3.{71}_{-0.31}^{+0.28}{}_{-0.35}^{+0.28}$. These values are consistent with the two-nucleon system exhibiting Wigner's supermultiplet symmetry, which becomes exact in the limit of large $N_c$. In both spin channels, the phase shifts change sign at higher momentum, near the start of the $t$-channel cut, indicating that the nuclear interactions have a repulsive core even at the SU(3)-symmetric point.

Background: Average energies of nuclear collective modes may be efficiently and accurately computed using a nonrelativistic constrained approach without reliance on a random phase approximation (RPA).

Purpose: To extend the constrained approach to the relativistic domain and to establish its impact on the calibration of energy density functionals.

Methods: Relativistic RPA calculations of the giant monopole resonance (GMR) are compared against the predictions of the corresponding constrained approach using two accurately calibrated energy density functionals.

Results: We find excellent agreement—at the 2% level or better—between the predictions of the relativistic RPA and the corresponding constrained approach for magic (or semimagic) nuclei ranging from ${}^{16}$O to ${}^{208}$Pb.

Conclusions: An efficient and accurate method is proposed for incorporating nuclear collective excitations into the calibration of future energy density functionals.

An in-beam study has been performed to further investigate the known isomeric decays and to identify $T=1$ excited states in the medium-heavy $N=Z=33$ nucleus ${}^{66}$As. The fusion-evaporation reaction ${}^{40}$Ca(${}^{28}$Si,$pn$)${}^{66}$As was employed at beam energies of 75 and 83 MeV. The half-lives and ordering of two known isomeric states in ${}^{66}$As have been determined with improved accuracy. In addition, several prompt $\gamma$-ray transitions from excited states, both bypassing and decaying to the isomeric states in ${}^{66}$As, have been observed. Most importantly, candidates for the $4^{+}\to 2^{+}$ and $6^{+}\to 4^{+}$ transitions in the $T=1$ band have been identified. The results are compared with shell-model calculations using the modern JUN45 interaction in the $p{f}_{5/2}{g}_{9/2}$ model space.

We evaluate semi-inclusive neutral-current quasielastic differential neutrino and antineutrino cross sections within the framework of the relativistic impulse approximation. The results of the relativistic mean-field and of the relativistic Green's function models are compared. The sensitivity to the strange-quark content of the nucleon form factor is also discussed. The results of the models are compared with the MiniBooNE experimental data for neutrino scattering. Numerical predictions for flux-averaged antineutrino scattering cross sections are also presented.

We update our recent analysis of $\overline{p}d$ scattering, performed within the Glauber theory including the single and double $\overline{p}N$ scattering mechanisms. Specifically, now we consider also $\overline{N}N$ amplitudes from a new partial-wave analysis of $\overline{p}p$ scattering data. Predictions for differential cross sections and the spin observables $A_y^d$, $A_y^{\overline{p}}$, $A_{xx}$, $A_{yy}$ are presented for antiproton beam energies between 50 and 300 MeV. Total polarized cross sections are calculated utilizing the optical theorem. The efficiency of the polarization buildup for antiprotons in a storage ring is investigated.

We study the electric dipole polarizability ${\alpha }_D$ in ${}^{208}$Pb based on the predictions of a large and representative set of relativistic and nonrelativistic nuclear mean-field models. We adopt the droplet model as a guide to better understand the correlations between ${\alpha }_D$ and other isovector observables. Insights from the droplet model suggest that the product of ${\alpha }_D$ and the nuclear symmetry energy at saturation density $J$ is much better correlated with the neutron skin thickness $\Delta r_{np}$ of ${}^{208}$Pb than the polarizability alone. Correlations of ${\alpha }_{D}J$ with $\Delta r_{np}$ and with the symmetry energy slope parameter $L$ suggest that ${\alpha }_{D}J$ is a strong isovector indicator. Hence, we explore the possibility of constraining the isovector sector of the nuclear energy density functional by comparing our theoretical predictions against measurements of both ${\alpha }_D$ and the parity-violating asymmetry in ${}^{208}$Pb. We find that the recent experimental determination of ${\alpha }_D$ in ${}^{208}$Pb in combination with the range for the symmetry energy at saturation density $J=[31\pm {\left(2\right)}_{\mathrm{est}}]$ MeV suggests $\Delta r_{np}\left({}^{208}\mathrm{Pb}\right)=0.165\pm {\left(0.009\right)}_{\mathrm{expt}}\pm {\left(0.013\right)}_{\mathrm{theor}}\pm {\left(0.021\right)}_{\mathrm{est}}\mathrm{fm}$ and $L=43\pm {\left(6\right)}_{\mathrm{expt}}\pm {\left(8\right)}_{\mathrm{theor}}\pm {\left(12\right)}_{\mathrm{est}}$ MeV.

The lifetime of the second excited 2${}^{+}$ state of ${}^{94}$Zr at 1671 keV was determined with the Doppler-shift attenuation method (DSAM) following the $(n,n^{\prime }\gamma )$ reaction on scattering samples of Zr metal and ZrO${}_2$ of natural isotopic abundance. The measured lifetime, $\tau ={368}_{-23}^{+27}$ fs, is considerably longer than the previous measurement, as are measured lifetimes of other levels in ${}^{94}$Zr. However, lifetimes of low-lying, low-spin states in ${}^{90,91,92,96}$Zr were also determined and found to be in good agreement with measurements employing non-DSAM methods. Possible reasons for the discrepant lifetimes measured for ${}^{94}$Zr are discussed and focus on the chemical properties of the scattering sample, specifically, the effects of using amorphous materials, or those composed of small particles as scattering samples. These properties have been investigated by x-ray powder diffraction and scanning electron microscopy. The effects of using these materials for lifetime measurements were investigated by employing, as scattering samples, Zr(OH)${}_4$ (a known amorphous material) and ZrO${}_2$ with various crystalline domain sizes.

The dynamic response of asymmetric nuclear matter is studied by means of a time-dependent local isospin density approximation (TDLIDA) approach. Calculations are based on a local density energy functional derived by an auxiliary field diffusion Monte Carlo (AFDMC) calculation of bulk nuclear matter. Three types of excited states emerge: collective states, a continuum of quasiparticle-quasihole excitations and unstable solutions. These states are analyzed and discussed for different values of the nuclear density $\rho$ and isospin asymmetry $\xi =(N-Z)/A$. An analytical expression of the compressibility as a function of $\rho$ and $\xi$ is derived which shows explicitly an instability of the neutron matter around $\rho \simeq 0.09$ fm${}^{-3}$ when a small fraction of protons are added to the system.

Background: Unravelling the role played by nonvalence flavors in baryons is crucial in deepening our comprehension of QCD. The strange quark, a component of the higher Fock states in baryons, is an appropriate tool to study nonperturbative mechanisms due to the pure sea quark.

Purpose: Study the magnitude and the sign of the strangeness magnetic moment ${\mu }_s$ and the magnetic form factor ($G_M^s$) of the proton.

Methods: Within an extended chiral constituent quark model, we investigate contributions from all possible five-quark components to ${\mu }_s$ and $G_M^s\left(Q^2\right)$ in the four-vector momentum range $Q^2\le 1$ (GeV/$c$)${}^2$. The probability of the strangeness component in the proton wave function is calculated employing the ${}^3{P}_0$ model.

Results: Predictions are obtained by using input parameters taken from the literature. The observables ${\mu }_s$ and $G_M^s\left(Q^2\right)$ are found to be small and negative, consistent with the lattice-QCD findings as well as with the latest data released by the PVA4 and HAPPEX Collaborations.

Conclusions: Due to sizable cancellations among different configurations contributing to the strangeness magnetic moment of the proton, it is indispensable to (i) take into account all relevant five-quark components and include both diagonal and nondiagonal terms, (ii) handle with care the oscillator harmonic parameter ${\omega }_5$ and the $s\overline{s}$ component probability.

A shape phase transition between stable octupole deformation and octupole vibrations in Th nuclei is analyzed in a microscopic framework based on nuclear density functional theory. The relativistic density dependent point coupling (DD-PC1) functional is used to calculate axially symmetric quadrupole-octupole constrained energy surfaces. Observables related to order parameters are computed using an interacting-boson Hamiltonian, with parameters determined by mapping the microscopic energy surfaces to the expectation value of the Hamiltonian in the boson condensate. The systematics of constrained energy surfaces and low-energy excitation spectra point to the occurrence of a phase transition between octupole-deformed shapes and shapes characterized by octupole-soft potentials.

In-source laser spectroscopy experiments for neutron-deficient thallium isotopes at the 276.9-nm atomic transition have been carried out at the Investigation of Radioactive Isotopes on Synchrocyclotron facility of Petersburg Nuclear Physics Institute. New data on isotope shifts and the hyperfine structure for ${}^{183-207}$Tl isotopes and isomers are presented. The changes in the mean-square charge radii and magnetic-moment values are deduced. It is shown that nuclear properties of Tl isotopes and isomers smoothly change at the neutron midshell and beyond without development of strong deformation in contrast to the adjacent Hg nuclei. A rather great isomer shift between $I$ $=$ 1/2 and $I$ $=$ 9/2 states for odd Tl isotopes is preserved for both sides of the previously investigated mass range. For the first time, a similar isomer shift is found for the odd-odd isotope ${}^{186}$Tl. The close resemblance of the charge radii isotopic behavior for the Tl and Pb ground states is demonstrated.

We examine how the signature of the strange-dibaryon resonances with $I=1/2$ and $J^{\pi }=0^{-}$ shows up in scattering amplitudes and observables of the three-body $\overline{K}NN$-$\pi YN(Y=\Sigma ,\Lambda )$ system on the physical real energy axis. The so-called point method is applied to handle logarithmic singularities that appear in solving the Alt-Grassberger-Sandhas equations for the real scattering energies. By taking two different kinds of models for the two-body $\overline{K}N$-$\pi \Sigma$ subsystem, both of which reproduce the available data equally well but give quite a different resonance-pole structure for $\Lambda \left(1405\right)$, we also investigate whether the strange-dibaryon production reactions can be used for disentangling the nature of $\Lambda \left(1405\right)$.

The $K^{+}{K}^{-}$ final state interaction was investigated based on both the $K^{+}{K}^{-}$ invariant mass distributions measured at excess energies of $Q=10$ and 28 MeV and the near threshold excitation function for the $pp\to pp{K}^{+}{K}^{-}$ reaction. The $K^{+}{K}^{-}$ final state enhancement factor was parametrized using the effective range expansion. The effective range of the $K^{+}{K}^{-}$ interaction was estimated to be $\mathrm{Re}\left(b_{K^{+}{K}^{-}}\right)=-0.1\pm 0.4_{\mathrm{stat}}\pm 0.3_{\mathrm{sys}}\mathrm{fm}$ and $\mathrm{Im}\left(b_{K^{+}{K}^{-}}\right)=1.2_{-0.2_{\mathrm{stat}}-0.0_{\mathrm{sys}}}^{+0.1_{\mathrm{stat}}+0.2_{\mathrm{sys}}}\mathrm{fm}$, and the determined real and imaginary parts of the $K^{+}{K}^{-}$ scattering length amount to $\left|\mathrm{Re}\left(a_{K^{+}{K}^{-}}\right)\right|=8.0_{-4.0_{\mathrm{stat}}}^{+6.0_{\mathrm{stat}}}\mathrm{fm}$ and $\mathrm{Im}\left(a_{K^{+}{K}^{-}}\right)=0.0_{-5.0_{\mathrm{stat}}}^{+20.0_{\mathrm{stat}}}\mathrm{fm}$.

We report here a determination of the asymptotic normalization coefficient of the valence neutron in ${}^8$Li from a measurement of the angular distribution of the ${}^7$Li(${}^8$Li,${}^7$Li)${}^8$Li reaction at 11 MeV. Using isospin symmetry the ${}^8$B ANC has also been calculated and used to infer a value for $S_{17}\left(0\right)$ of 20.2 $\pm$ 4.4 eV b.