We calculate the shear viscosity η and thermal conductivity κ of a nuclear pasta phase in neutron star crusts. This involves complex nonspherical shapes. We use semiclassical molecular dynamics simulations involving 40, 000 to 100, 000 nucleons. The viscosity η can be simply expressed in terms of the height $Z^{*}$ and width $\Delta q$ of the peak in the static structure factor $S_p(q)$. We find that η increases somewhat, compared to a lower density phase involving spherical nuclei, because $Z^{*}$ decreases from form factor and ion screening effects. However, we do not find a dramatic increase in η from nonspherical shapes, as may occur in conventional complex fluids.

We develop a formalism for studying vector-meson ($V$) photoproduction at the proton ($p$) with polarized photons, $\overrightarrow{\gamma }p\to Vp$, through an analysis of the decay distribution in the channel $V\to {\pi }^0\gamma$. We show that this decay distribution differs noticeably from the distributions of purely hadronic decays, like $\varphi \to K^{+}{K}^{-}$ and $\omega \to {\pi }^0{\pi }^{+}{\pi }^{-}$. Formulas for the decay distributions are presented that are suitable for data analysis and interpretation.

We study a particular class of relativistic nuclear energy density functionals in which only nucleon degrees of freedom are explicitly used in the construction of effective interaction terms. Short-distance (high-momentum) correlations, as well as intermediate- and long-range dynamics, are encoded in the medium (nucleon-density) dependence of the strength functionals of an effective interaction Lagrangian. Guided by the density dependence of microscopic nucleon self-energies in nuclear matter, a phenomenological ansatz for the density-dependent coupling functionals is accurately determined in self-consistent mean-field calculations of binding energies of a large set of axially deformed nuclei. The relationship between the nuclear matter volume, surface, and symmetry energies and the corresponding predictions for nuclear masses is analyzed in detail. The resulting best-fit parametrization of the nuclear energy density functional is further tested in calculations of properties of spherical and deformed medium-heavy and heavy nuclei, including binding energies, charge radii, deformation parameters, neutron skin thickness, and excitation energies of giant multipole resonances.

Correction terms generated in the correlator analysis due to multiplicity-dependent observable mean are investigated. A procedure for the subtraction of correction terms from the correlators evaluated at fixed observed multiplicity is described. Benefits from the measurement of higher-order correlators are briefly discussed.

We calculate in the impulse approximation the kaon spectrum from the $({\pi }^{-},K^{+})$ reaction on ${}^{28}\mathrm{Si}$. The strength $V_{\Sigma }$ of the real part of the single particle potential of the $\Sigma$ hyperons produced in the reaction is obtained from the Nijmegen model F of the baryon-baryon interaction, and the strength $W_{\Sigma }$ of the imaginary (absorptive) part is determined by the $\Sigma N$ cross sections for the $\Sigma \Lambda$ conversion and also for the elastic $\Sigma N$ scattering (this elastic scattering introduces a strong dependence of $W_{\Sigma }$ on the $\Sigma$ momentum). The momentum dependence of $V_{\Sigma }$ is also considered. Our calculated inclusive kaon spectrum agrees reasonably with the spectrum measured at KEK. The strengths of the real and absorptive $\Sigma$ potentials used in the present calculation are compatible with these strengths determined in the analyses of $\Sigma$ atoms and of the strangeness exchange reactions.

The cranking model is used to describe rotational bands. We investigate the approach of using diabatic configurations and minimizing the particle-number projected energy in a mesh of both $\lambda ,\Delta$ and deformation parameters. We use the method to interpret recent experimental data in ${}^{142}\mathrm{Gd}$ and conclude that for the highest spin states observed ($I\approx 30$), the nucleus is triaxial and builds spin by rotating around the classically unfavored longest axis.

Low-lying multiphonon states in ${}^{136}\mathrm{Ba}$ have been populated with the inelastic neutron scattering reaction. Excitation functions were performed at neutron energies from 2.2 to 3.9 MeV, and $\gamma$-ray angular distributions were measured at 2.5, 3.0, and 3.5 MeV. Lifetimes have been determined using the Doppler-shift attenuation method, and electromagnetic transition rates have been deduced. The previously assigned $2_{1,\mathrm{ms}}^{+}$ mixed-symmetry state at 2128.9 keV has been confirmed and is not greatly fragmented. For the first time in the $N=80$ isotones, a $3_{2,\mathrm{ms}}^{+}$ two-phonon mixed-symmetry state is proposed. In addition, the $2_5^{+}$ and the $4_3^{+}$ levels at 2222.7 and 2356.4 keV, respectively, decay with large $B(M1)$ values to the two-phonon $2_2^{+}$ and $4_1^{+}$ states, respectively, which suggests two-phonon mixed-symmetric character. Their excitation energies, however, are not consistent with this interpretation.

The neutron capture cross section of ${}^{241}\mathrm{Am}$ for incident neutrons from 0.02 eV to 320 keV has been measured with the detector for advanced neutron capture experiments (DANCE) at the Los Alamos Neutron Science Center. The thermal neutron capture cross section was determined to be $665\pm 33$ b. Our result is in good agreement with other recent measurements. Resonance parameters for $E_n<12$ eV were obtained using an $R$-matrix fit to the measured cross section. The results are compared with values from the ENDF/B-VII.0, Mughabghab, JENDL-3.3, and JEFF-3.1 evaluations. ${\Gamma }_n$ neutron widths for the first three resonances are systematically larger by 5–15% than the ENDF/B-VII.0 values. The resonance integral above 0.5 eV was determined to be 1553±7 b. Cross sections in the resolved and unresolved energy regions above 12 eV were calculated using the Hauser-Feshbach theory incorporating the width-fluctuation correction of Moldauer. The calculated results agree well with the measured data, and the extracted averaged resonance parameters in the unresolved resonance region are consistent with those for the resolved resonances.

Nuclear reactions leading to the formation of new superheavy (SH) elements and isotopes are discussed in the paper. “Cold” and “hot” synthesis, fusion of fission fragments, transfer reactions, and reactions with radioactive ion beams are analyzed along with their abilities and limitations. If the possibility of increasing the beam intensity and the detection efficiency (by a total of one order of magnitude) is found, then several isotopes of new elements with $Z=120\text{−}124$ could be synthesized in fusion reactions of titanium, chromium, and iron beams with actinide targets. The use of light- and medium-mass neutron-rich radioactive beams may help us fill the gap between the SH nuclei produced in the hot fusion reactions and the mainland. In these reactions, we may really approach the “island of stability.” Such a possibility is also provided by the multinucleon transfer processes in low-energy damped collisions of heavy actinide nuclei. The production of SH elements in fusion reactions with accelerated fission fragments looks less encouraging.

We calculate the Coulomb dissociation of ${}^9\mathrm{Li}$ on Pb and U targets at 28.5 MeV/A beam energy within a finite range distorted wave Born approximation formalism of the breakup reactions. Invoking the principle of detailed balance, these cross sections are used to determine the excitation function and subsequently the rate of the radiative capture reaction ${}^8\mathrm{Li}(n,\gamma ){}^9\mathrm{Li}$ at astrophysical energies. Our method is free from the uncertainties associated with the multipole strength distributions of the ${}^9\mathrm{Li}$ nucleus. The rate of this reaction at a temperature of 10 K is found to be about 2900 ${\mathrm{cm}}^3$ ${\mathrm{mole}}^{-1}$ ${\mathrm{s}}^{-1}$.

The structure of ${}_6^{17-20}\mathrm{C}$ nuclei was investigated by means of the in-beam $\gamma$-ray spectroscopy technique using fragmentation reactions of radioactive beams. Based on particle-$\gamma$ and particle-$\gamma \gamma$ coincidence data, level schemes are constructed for the neutron-rich ${}^{17-20}\mathrm{C}$ nuclei. The systematics of the first excited $2^{+}$ states in the carbon isotopes is extended for the first time to $A=20$ showing that in contrast to the case of the oxygen isotopes, the $N=14$ subshell closure disappears. Experimental results are compared with shell-model calculations. Agreement between them is found only if a reduced neutron-neutron effective interaction is used. Implications of this reduced interaction in some properties of weakly bound neutron-rich Carbon are discussed.

We perform an extensive analysis of $\alpha$-decays to $2^{+}$ and $4^{+}$ states in deformed even-even nuclei by using the stationary coupled channels approach. Collective excitations are described within the rigid rotor model. The $\alpha$-nucleus interaction is given by a double folding procedure with M3Y plus Coulomb nucleon-nucleon forces. We use a repulsive potential with one independent parameter in order to localize the $\alpha$-particle on the nuclear surface and to fit the experimental $Q$-value. The decaying state is identified with the first resonance inside the resulting pocket-like potential, as suggested by microscopic calculations. We obtain a good agreement with existing experimental data concerning decay widths to $J=2^{+},4^{+}$ states. The total $\alpha$-decay half-lives agrees very well with experimental values by fitting the spectroscopic factor in terms of charge and neutron numbers separately for $Z<82$ and $Z>82$. We give predictions for intensities and hindrance factors for 52 even-even $\alpha$-emitters with ${\beta }_2>0.15$ and $E_{2^{+}}<200\hspace{0.5em}\mathrm{kev}$. Comparison between the phenomenological and microscopic spectroscopic factors revealed large $\alpha$-clustering components for nuclei close and above $N=82,Z=82,N=126$ magic numbers.

Our experiment using gravitationally trapped ultracold neutrons (UCN) to measure the neutron lifetime is reviewed. Ultracold neutrons were trapped in a material bottle covered with perfluoropolyether. The neutron lifetime was deduced from comparison of UCN losses in the traps with different surface-to-volume ratios. The precise value of the neutron lifetime is of fundamental importance to particle physics and cosmology. In this experiment, the UCN storage time is brought closer to the neutron lifetime than in any experiments before: the probability of UCN losses from the trap was only 1% of that for neutron $\beta$ decay. The neutron lifetime obtained, $878.5\pm 0.7_{\mathrm{stat}}\pm 0.3_{\mathrm{sys}}$ s, is the most accurate experimental measurement to date.

High-spin states in ${}^{80}\mathrm{Sr}$ were studied using the ${}^{54}\mathrm{Fe}({}^{28}\mathrm{Si},2p)$ reaction at 90 MeV and the ${}^{58}\mathrm{Ni}({}^{28}\mathrm{Si},\alpha 2p)$ reaction at 110 MeV. Prompt $\gamma \text{−}\gamma$ coincidences were measured from the ${}^{54}\mathrm{Fe}({}^{28}\mathrm{Si},2p)$ reaction using an array of 10 Compton-suppressed Ge detectors. $\gamma$-ray linear polarizations were measured in both reactions using three clover detectors as Compton polarimeters. Negative parity has been conclusively assigned to one band and is favored for two others based on the polarization measurements and the observation of six new linking transitions between the bands near their band heads. This evidence supports a picture of strong mixing between low-lying states with negative parity, similar to what has been observed in ${}^{82}\mathrm{Sr}$. Directional correlation of oriented nuclei ratios support the spin assignments made in the most recent in-beam study.

Lifetimes of chiral candidate structures in ${}^{103,104}\mathrm{Rh}$ were measured using the recoil distance Doppler-shift method. The Gammasphere detector array was used in conjunction with the Cologne plunger device. Excited states of ${}^{103,104}\mathrm{Rh}$ were populated by the ${}^{11}\mathrm{B}({}^{96}\mathrm{Zr},4n){}^{103}\mathrm{Rh}$ and ${}^{11}\mathrm{B}({}^{96}\mathrm{Zr},3n){}^{104}$Rh fusion-evaporation reactions in inverse kinematics. Three and five lifetimes of levels belonging to the proposed chiral doublet bands are measured in ${}^{103}\mathrm{Rh}$ and ${}^{104}\mathrm{Rh}$, respectively. The previously observed even-odd spin dependence of the $B(M1)/B(E2)$ values is caused by the variation in the $B(E2)$ values, whereas the $B(M1)$ values decrease as a function of spin.

The $2_1^{+}$ states of ${}^{114,116}\mathrm{Sn}$ were excited in two consecutive experiments by means of Coulomb excitation in inverse kinematics on a ${}^{58}\mathrm{Ni}$ target. A precise determination of the reduced transition probability $B(E2$; $0_{\mathrm{g}.\mathrm{s}.}^{+}\to 2_1^{+})$ of ${}^{114}\mathrm{Sn}$ relative to the well-known $2_1^{+}$ excitation strength in ${}^{116}\mathrm{Sn}$ was achieved by comparing the relative projectile to target $2_1^{+}\to 0_{\mathrm{g}.\mathrm{s}.}^{+}$ decay intensities. The obtained $B(E2\uparrow )$ value of $0.232(8)\hspace{0.5em}{e}^2{\mathrm{b}}^2$ for ${}^{114}\mathrm{Sn}$ confirms the tendency of large $B(E2\uparrow )$ values for the light tin isotopes below the midshell ${}^{116}\mathrm{Sn}$ that has been observed recently in various radioactive ion beam experiments. The result establishes most clearly the discrepancy between the current $B(E2\uparrow )$ value predictions from large-scale shell-model calculations and the experimental deviation, which commences already for the stable ${}^{114}\mathrm{Sn}$ isotope.

Excited states in ${}^{131}\mathrm{Cs}$ were investigated through in-beam $\gamma$-ray spectroscopic techniques following its population in the ${}^{124}\mathrm{Sn}$(${}^{11}\mathrm{B}$, $4n$) fusion-evaporation reaction at a beam energy of 46 MeV. The previously known level scheme has been substantially extended up to $\sim$9 MeV excitation energy and $49/2\hslash$ spin with the addition of seven new band structures. The present level scheme consisting of 15 bands exhibits a variety of collective features in this nucleus at intermediate spin. The excitation energies of the observed levels in different bands and the corresponding ratios of transition strengths, i.e., $B(M1)/B(E2)$, have been compared with the results of projected deformed Hartree-Fock calculations based on various quasiparticle configurations. A strongly coupled band has been reassigned a high-$K$ three-quasiparticle $\pi h_{11/2}\otimes \nu (h_{11/2}{d}_{3/2})$ configuration based on the properties of this band and that of its new coupled side band. The configurations of these bands are also discussed in the framework of tilted-axis cranking model calculations and the systematics of the odd-$A$ Cs isotopes. Additional three energetically closely placed coupled bands have been assigned different unpaired three-quasiparticle configurations. $\gamma$-vibrational bands coupled to the $\pi h_{11/2}$ and $\pi g_{7/2}$ single-particle configurations have been reported in this nucleus. Observation of new $E1$ transitions linking the opposite-parity $\pi h_{11/2}$ and $\pi d_{5/2}$ bands provides fingerprints of possible octupole correlations.

The self-consistent Hartree-Fock-Bogoliubov approximation based on the finite-range and density-dependent Gogny interaction (parametrization D1S) has been used to generate potential energy curves in various chains of Pd, Xe, Ba, Nd, Sm, Gd, and Dy isotopes. The evolution of shapes with the number of nucleons is studied and a search for signatures of E(5) and X(5) critical point symmetries is also conducted. The results are compared with those obtained in the framework of other mean-field approximations to the nuclear many-body problem. The role of triaxiality in nuclei where this degree of freedom could be relevant is considered and discussed.

The implication of chiral symmetry for the pion-induced dissociation of the $J/\psi$ is examined in detail. It is shown how the low-energy dynamics of pions, constrained by chiral symmetry, affect the dissociation cross section. The derived soft-pion theorem is then integrated into a Lagrangian model that includes also abnormal parity content and chiral-symmetric form factors. Dissociation by the ρ meson is also considered.