The shell effect and isospin effect in nuclear charge radii are systematically investigated, and a four-parameter formula is proposed for the description of the root-mean-square (rms) charge radii by combining the shell corrections and deformations of nuclei obtained from the Weizsäcker-Skyrme mass model. The rms deviation with respect to the 885 measured charge radii falls to 0.022 fm. The proposed formula is also applied for the study of the charge radii of superheavy nuclei and nuclear symmetry energy. The linear relationship between the slope parameter $L$ of the nuclear symmetry energy and the rms charge radius difference of the ${}^{30}\mathrm{S}-{}^{30}\mathrm{Si}$ mirror pair is clearly observed. The estimated slope parameter is about $L=54\pm 19\mathrm{MeV}$ from the coefficient of the isospin term in the proposed charge radius formula.

A hybrid experiment with nuclear emulsion and scintillating-fiber detectors (KEK-E373) has been performed to search for double-strangeness systems. Among about 10${}^3$ events of ${\Xi }^{-}$ hyperons captured at rest by emulsion nuclei, we have observed four events which clearly show the topology of cascade weak decays of double-$\Lambda$ hypernuclei including the “Nagara” event. Regarding the Nagara event, values of the two-$\Lambda$ binding energy ($B_{\Lambda \Lambda }$) and the $\Lambda$-$\Lambda$ interaction energy ($\Delta B_{\Lambda \Lambda }$) of ${}_{\Lambda }^{}{}_{\Lambda }^6\mathrm{He}$ have been revised to 6.91 $\pm$ 0.16 and 0.67 $\pm$ 0.17 MeV, respectively, due to the recent change of the ${\Xi }^{-}$ mass value (Particle Data Group). For another three events, we have determined possible species of double-$\Lambda$ hypernuclei together with their binding energies.

The Airy structure of the nuclear rainbow and prerainbow in inelastic and elastic $\alpha +{}^{16}$O scattering is studied with the coupled channel method using a folding potential derived from the microscopic wave functions of ${}^{16}$O. The theoretical calculations reproduce the characteristic energy evolution of the Airy minimum of the experimental angular distributions. The energy levels with $\alpha$-cluster structure in ${}^{20}$Ne are reproduced well using the potentials determined from the analysis of scattering. It is shown that the emergence of the $K=0_3^{+}$ $\alpha$-cluster band with core excitation at 7.19 MeV in ${}^{20}$Ne is intimately related to the emergence of the prerainbow and rainbow in inelastic scattering to the ${}^{16}$O($0_2^{+}$). It is found that the $\alpha$-cluster states with core excitation, the prerainbow and the rainbow in inelastic scattering are understood in a unified way as well as in the case of elastic scattering.

The occurrence of low-energy collective motion is a widespread phenomenon in quantum systems. To describe fluctuations about the equilibrium deformation and to understand the nature of excited $0^{+}$ states in deformed nuclei, we improve the many-body wave functions by superimposing angular-momentum-projected states constructed with different quadrupole deformations. We take deformed rare-earth nuclei as examples, compare quantitatively the calculated low-lying $0^{+}$ bands and the associated electric monopole transition matrix elements with experimental data. The analysis of the resulting wave functions for the excited $0^{+}$ states indicates clear features of quantum oscillations, with large fluctuations in deformation for soft nuclei and strong anharmonicities in the oscillations for rigidly deformed nuclei.

Background: The cross section for forming a heavy evaporation residue in fusion reactions depends on the capture cross section, the fusion probability, $P_{\mathrm{CN}}$, i.e., the probability that the projectile-target system will evolve inside the fission saddle point to form a completely fused system rather than reseparating (quasifission), and the survival of the completely fused system against fission. $P_{\mathrm{CN}}$ is the least known of these quantities.

Purpose: We want to determine $P_{\mathrm{CN}}$ for the reactions of 101.2 MeV ${}^{18}$O, 147.3 MeV ${}^{26}$Mg, 170.9 MeV ${}^{30}$Si, and 195.3 MeV ${}^{36}$S with ${}^{197}$Au.

Methods: We measured the fission fragment angular distributions for these reactions and used the formalism of Back to deduce the fusion-fission and quasifission cross sections. From these quantities we deduced $P_{\mathrm{CN}}$ for each reaction.

Results: The values of $P_{\mathrm{CN}}$ for the reactions of 101.2 MeV ${}^{18}$O, 147.3 MeV ${}^{26}$Mg, 170.9 MeV ${}^{30}$Si, and 195.3 MeV ${}^{36}$S with ${}^{197}$Au are 0.66, 1.00, 0.06, and 0.13, respectively.

Conclusions: The new measured values of $P_{\mathrm{CN}}$ agree roughly with the semiempirical systematic dependence of $P_{\mathrm{CN}}$ upon fissility for excited nuclei.

The value of the $\Lambda \left(1405\right)\overline{K}N$ coupling constant $g_{\Lambda \left(1405\right)\overline{K}N}$ is obtained by fitting it to the experimental data on the total cross sections of the $K^{-}p\to {\pi }^0{\Sigma }^0$ reaction. On the basis of an effective Lagrangian approach and isobar model, we show that the value $|g_{\Lambda \left(1405\right)\overline{K}N}|=1.51\pm 0.10$ could be extracted from the available experimental data by assuming that the $s$-channel $\Lambda \left(1405\right)$ resonance plays a dominant role, whereas, the background contributions from the $s$-channel $\Lambda \left(1115\right)$, $t$-channel $K^{*}$, and $u$-channel nucleon pole processes are small and can be neglected. However, the $u$-channel nucleon pole diagram may also give an important contribution in the present calculations. After the background contributions are taken into account, the above value of $g_{\Lambda \left(1405\right)\overline{K}N}$ is reduced to $|g_{\Lambda \left(1405\right)\overline{K}N}|=0.77\pm 0.07$, which is not supported by the previous calculations and the recent CLAS measurements. The theoretical calculations on differential cross sections are also presented, which can be checked by future experiments.

Calculations are presented for incoherent $J/\psi$ electroproduction from the deuteron at Jefferson Laboratory energies, including the effects of $J/\psi$-nucleon rescattering in the final state, in order to determine the feasibility of measuring the $J/\psi$-nucleon scattering length, or the $J/\psi$-nucleon scattering amplitude at lower relative energies than in previous measurements. It is shown that for a scattering length of the size predicted by existing theoretical calculations, it would not be possible to determine the scattering length. However, it may be possible to determine the scattering amplitude at significantly lower relative energies than the only previous measurements.

A coupled-channel model with $\pi N$, $\rho N$, and $J/\Psi N$ channels is developed to predict the $\pi +N\to J/\Psi +N$ cross sections. The $J/\Psi$-$N$ interaction is parameterized in a form related to what has been predicted by the effective field theory approach and lattice QCD. The other interactions within the model are constrained by the decay width of $J/\Psi \to \rho +\pi$ and the total cross-sectional data of $\pi N$ reactions. The calculated meson-baryon amplitudes are then used to predict the cross sections of the $J/\Psi$ production on the deuteron target by including the contributions from the impulse term and the one-loop calculations of the final $NN$ and $J/\Psi N$ rescattering effects. Predictions of the dependence of the cross sections of ${\pi }^{-}+p\to J/\Psi +n$, $\gamma +d\to J/\Psi +n+p$, and ${\pi }^{+}d\to J/\Psi +p+p$ on the $J/\Psi$-$N$ potentials are presented to examine the feasibility of experimental determinations of the $J/\Psi$-$N$ interaction. Within the vector meson dominance model, we have also applied the constructed coupled-channel model to predict the $\gamma +p\to J/\Psi +p$ cross sections near the $J/\Psi$ production threshold.

Deep inelastic and transfer reactions with an 820-MeV, ${}^{136}$Xe beam and various ytterbium and lutetium targets have been employed to study high-spin structures in the neutron-rich thulium isotopes beyond ${}^{171}$Tm. Results in the doubly odd nucleus, ${}^{174}$Tm, include the identification of numerous new two- and four-quasiparticle intrinsic states including several isomers below 1 MeV, and the observation of the $K^{\pi }=4^{-}$ ground state rotational band populated via direct decay from a $\tau =153\left(10\right)-\mu$s, $K^{\pi }={14}^{-}$ isomer at 2092 keV. The 398-keV, $M$1 transition linking the isomer and ground state band is abnormally fast for a highly forbidden, $\Delta K=10$ decay. This relative enhancement is explained in terms of mixing of the 13${}^{-}$ level with the nearby 13${}^{-}$ member of a $K^{\pi }=8^{-}$ rotational band, with an interaction strength of V $\approx$ 1.4 keV. Multiquasiparticle calculations are compared with the observed states.

Whether or not the ${}^{178}$Hf${}^{m2}$ isomer has the characteristic of induced γ emission by low-energy x rays has been a focus of attention for many scientists and researchers in recent decades. In this paper, an experiment regarding triggering ${}^{178}$Hf${}^{m2}$ emission decay is conducted at Shanghai Synchrotron Radiation Facility. An x-ray beam with 20.825-keV energy irradiates a rectangular sample containing about 10${}^{11178}$Hf${}^m$${}^2$ nuclides. By comparing the net gamma count rates during the irradiation with those after the irradiation, the data show that at the 426-, 495-, and 574-keV gamma lines, there is no significant enhancement, indicating that the induced γ decay of ${}^{178}$Hf${}^{m2}$ has not been observed.

Electron capture (EC) decay of ${}^{146}$Gd ($t_{\frac{1}{2}}=48$ d) to the low lying states of ${}^{146}$Eu has been studied using high-resolution $\gamma$-ray spectroscopy. The ${}^{146}$Gd activity was produced by ($\alpha ,2n$) reaction at $E_{\alpha }=32$ MeV using a 93.8$\%$ enriched ${}^{144}$Sm target. The level structure has been considerably modified from the measurement of $\gamma$-ray singles, $\gamma \gamma$ coincidences and decay half lives. Lifetime measurement has been performed for the 3${}^{-}$ (114.06 keV) and 2${}^{-}$ (229.4 keV) levels of ${}^{146}$Eu using the mirror symmetric centroid difference (MSCD) method with LaBr${}_3$ (Ce) detectors. The lifetimes for these two states have been found to be 5.38 $\pm$ 2.36 ps and 8.38 $\pm$ 2.19 ps respectively. Shell model calculation has been performed using oxbash code in order to interpret the results.

The excitation spectra in the deformed nucleus ${}^{228}$Th have been studied by means of the ($p,t$) reaction, using the Q3D spectrograph facility at the Munich Tandem accelerator. The angular distributions of tritons were measured for about 110 excitations seen in the triton spectra up to 2.5 MeV. Firm $0^{+}$ assignments are made for 17 excited states by comparison of experimental angular distributions with the calculated ones using the chuck3 code. Assignments up to spin $6^{+}$ are made for other states. Sequences of states are selected which can be treated as rotational bands and as multiplets of excitations. Moments of inertia have been derived from these sequences, whose values may be considered as evidence of the two-phonon nature of most $0^{+}$ excitations. Experimental data are compared with interacting boson model and quasiparticle-phonon model calculations and with experimental data for ${}^{229}$Pa.

We report measurements of the third harmonic coefficient of the azimuthal anisotropy, $v_3$, known as triangular flow. The analysis is for charged particles in Au+Au collisions at $\sqrt{s_{\mathit{NN}}}=200$ GeV, based on data from the STAR experiment at the BNL Relativistic Heavy Ion Collider. Two-particle correlations as a function of their pseudorapidity separation are fit with narrow and wide Gaussians. Measurements of triangular flow are extracted from the wide Gaussian, from two-particle cumulants with a pseudorapidity gap, and also from event plane analysis methods with a large pseudorapidity gap between the particles and the event plane. These results are reported as a function of transverse momentum and centrality. A large dependence on the pseudorapidity gap is found. Results are compared with other experiments and model calculations.

We study the effect of parton angular momentum on the twist-four correction to the left-right asymmetry in the electron-deuteron parity-violating deep-inelastic scattering (PVDIS). We show that this higher-twist correction is transparent to the dynamics of parton angular momentum needed to account for the Sivers and Boer-Mulders functions and spin-independent parton distribution functions. A sufficiently precise measurement of the PVDIS asymmetry may, thus, provide additional information about the parton dynamics responsible for nucleon spin.

Photoneutron cross sections were measured for ${}^{94}$Mo, ${}^{95}$Mo, ${}^{96}$Mo, ${}^{97}$Mo, ${}^{98}$Mo, and ${}^{100}$Mo near the neutron threshold with quasi-monochromatic laser-Compton scattering $\gamma$ rays. The photoneutron data were analyzed with the Skyrme Hartree-Fock-Bogoliubov (HFB) plus quasiparticle random phase approximation (QRPA) model and the axially symmetric-deformed Gogny HFB plus QRPA model of $E1$ $\gamma$-ray strength. Combining the $\gamma$-ray strength function constrained by the present photoneutron data with either the nuclear resonance fluorescence data or the updated Oslo data to supplement the data below the neutron threshold, a thorough analysis of the reverse $(n,\gamma )$ cross sections is made whenever measurements are available. The Oslo data and the corresponding uncertainties are updated based on the latest results of the $s$-wave neutron spacing and the average radiative width determined in particular for ${}^{96}$Mo. Finally, radiative neutron capture cross sections for two radioactive nuclei, ${}^{93}$Mo and ${}^{99}$Mo, are deduced with the $\gamma$-ray strength function method.

We calculate $\beta$-transition rates for URCA nuclear pairs using the $sd$-shell-model framework of Wildenthal [B. H. Widenthal, Prog. Part. Nucl. Phys. 11, 5 (1984)] with the modified Hamiltonian. We consider many $\beta$ transitions including excited states necessary for electron capture and $\beta$ decay with high Fermi energy of electrons at high electron density $\rho Y_e$ and temperature $T$ relevant for the massive star and super-asymptotic-giant-branch star evolution. We provide $\beta$-transition rates for URCA nuclear pairs ($A=23$, 25, and 27) in the range of density 8.0 $<{\log }_{10}\rho Y_e<$ 9.2 in steps of 0.02 ($Y_e$ is the electron mole number and $\rho$ is the nucleon density in units of g cm${}^{-3}$) and temperature 8.0 $<{\log }_{10}T<$ 9.2 in steps of 0.05 ($T$ is the temperature in units of K). This fine mesh is able to provide clearly the URCA density at ${\log }_{10}\rho Y_e=8.92$ for $A=23$ and at ${\log }_{10}\rho Y_e=8.81$ for $A=25$, while the URCA density is not clear for $A=27$. For the evolution of 8–10$M_{\odot }$ stars, the use of the fine mesh is found to increase the cooling effect and affects the final fate of these stars.

Background: Pion production gives information on the axial form factors of nucleon resonances. It also introduces a noticeable background to quasielastic measurements on nuclear targets and thus has a significant impact on precision studies of neutrino oscillation parameters.

Purpose: To clarify neutrino-induced pion production on nucleons and nuclei.

Method: The Giessen Boltzmann-Uehling-Uhlenbeck model is used for the description of neutrino-nucleus reactions.

Results: Theoretical results for differential cross sections for the T2K neutrino flux at the ND280 detector and integrated cross sections as a function of neutrino energy are given. Two sets of pion production data on elementary targets are used as inputs to obtain limits for pion production in neutrino-nucleus reactions.

Conclusions: Pion production in the T2K ND280 detector can help to narrow down the uncertainties in the elementary pion production cross sections. It can also give valuable information on the nucleon-$\Delta$ axial form factor.

Short-lived neutron-rich nuclei including ${}^{93}$Br, ${}^{93}$Kr, and ${}^{94}$Kr were produced in proton-induced fission of ${}^{238}$U at the Holifield Radioactive Ion Beam Facility in Oak Ridge. Their $\beta$ decay was studied by means of a high-resolution online mass separator and $\beta$–$\gamma$ spectroscopy methods. The half-life of $T_{1/2}$ $=$ 152(8) ms and $\beta$-delayed branching ratio of $P_n$ $=$ ${53}_{-8}^{+11}$% measured for ${}^{93}$Br differs from the previously reported values of $T_{1/2}$ $=$ 102(10) ms and $P_n$ $=$ 68(7)%. At the same time the half-life of ${}^{94}$Kr $T_{1/2}$ $=$ 227(14) ms and both the half-life of $T_{1/2}$ $=$ 1.298(54) s and $\beta$-delayed branching ratio of $P_n$ $=$ $1.9_{-0.2}^{+0.6}$% of ${}^{93}$Kr are in very good agreement with literature values. The decay properties of ${}^{93}$Br include previously unreported $\gamma$ transitions following $\beta$-delayed neutron emission.