The scandium isotopes ${}^{44,45}\mathrm{Sc}$ were studied with the ${}^{45}\mathrm{Sc}$(${}^3\mathrm{He}$, $\alpha \gamma$)${}^{44}\mathrm{Sc}$ and ${}^{45}\mathrm{Sc}$(${}^3\mathrm{He}$, ${}^3\mathrm{He}$${}^{\text{'}}\gamma$)${}^{45}\mathrm{Sc}$ reactions, respectively. The nuclear level densities and γ-ray strength functions have been extracted using the Oslo method. The experimental level densities are compared to calculated level densities obtained from a microscopic model based on BCS quasiparticles within the Nilsson level scheme. This model also gives information about the parity distribution and the number of broken Cooper pairs as a function of excitation energy. The experimental γ-ray strength functions are compared to theoretical models of the $E1$, $M1$, and $E2$ strength and to data from (γ, $n$) and (γ,$p$) experiments. The strength functions show an enhancement at low γ energies that cannot be explained by the present standard models.

We present the first systematic calculations based on the angular momentum projection of cranked Slater determinants. We propose the $I_y\to I$ scheme, by which one projects the angular momentum $I$ from the one-dimensional cranked state constrained to the average spin projection of $\langle {Î}_y\rangle =I$. Calculations performed for the rotational band in ${}^{46}\mathrm{Ti}$ show that the AMP $I_y\to I$ scheme offers a natural mechanism for correcting the cranking moment of inertia at low spins and shifting the terminating state up by $~2$ MeV, in accordance with data. We also apply this scheme to high-spin states near the band termination in $A~44$ nuclei and compare results thereof with experimental data, shell-model calculations, and results of the approximate analytical symmetry-restoration method proposed previously.

We discuss the information that can be deduced from a measurement of hadron (hyperon or vector meson) polarization in ultrarelativistic nuclear collisions. We describe the sensitivity of polarization to initial conditions, hydrodynamic evolution, and mean free path and find that the polarization observable is sensitive to all details and stages of the system's evolution. We suggest that an experimental investigation covering production plane and reaction plane polarizations, as well as the polarization of jet-associated particles in the plane defined by the jet and particle direction, can help in disentangling the factors contributing to this observable. Scans of polarization in energy and rapidity might also point to a change in the system's properties.

A relativistic transport model (ART1.0) is applied to simulate the stopping effects in tip-tip and body-body U+U collisions, at a beam kinetic energy of 520 MeV/nucleon. Our simulation results have demonstrated that both central collisions of the two extreme orientations can achieve full stopping and also form a bulk of hot, dense nuclear matter with a sufficiently large volume and long duration, because of the largely deformed uranium nuclei. The nucleon sideward flow in the tip-tip collisions is nearly three times larger than that in body-body ones at the normalized impact parameter $b/b_{\max }<0.5$, and that the body-body central collisions have a large negative nucleon elliptic flow $v_2=-12$% in contrast to zero in tip-tip ones. Thus the extreme circumstance and the novel experimental observables in tip-tip and body-body collisions can provide a good condition and sensitive probe for studying the nuclear EoS, respectively. The cooling storage ring (CSR) external target facility (ETF) to be built at Lanzhou, China, delivering a uranium beam up to 520 MeV/nucleon is expected to make a significant contribution to exploring the nuclear equation of state (EoS).

The ${}^2\mathrm{H}$(${}^{82}\mathrm{Ge}$,$p$)${}^{83}\mathrm{Ge}$ and ${}^2\mathrm{H}$(${}^{84}\mathrm{Se}$,$p$)${}^{85}\mathrm{Se}$ reactions were studied with radioactive beams of ${}^{82}\mathrm{Ge}$ and ${}^{84}\mathrm{Se}$ at beam energies of $E_{\mathrm{beam}}=330$ and 380 MeV, respectively. Excitation energies, proton angular distributions, and asymptotic normalization coefficients have been determined for the lowest lying states of ${}^{83}\mathrm{Ge}$ and ${}^{85}\mathrm{Se}$. Spectroscopic factors have also been extracted under normal assumptions of the bound-state potential properties in the distorted waves Born approximation analysis. However, the peripheral character of the measurements leads to large uncertainties in this extraction. Shell-model calculations have been performed in the region above ${}^{78}\mathrm{Ni}$, comparing the single-particle properties of the even-$Z,N=51$ nuclei up to ${}^{91}\mathrm{Zr}$ and including ${}^{83}\mathrm{Ge}$ and ${}^{85}\mathrm{Se}$. Direct-semidirect neutron capture calculations to ${}^{83}\mathrm{Ge}$ and ${}^{85}\mathrm{Se}$ have also been performed using the spectroscopic input from these $(d,p)$ reaction measurements.

We present a global spherical optical model for nucleons with incident energies up to 200 MeV containing dispersive terms and a local energy approximation. This optical model was built from our previous neutron optical model and is able to reproduce scattering data as well as bound single-particle states for neutrons and protons. However, for the scattering of protons, the situation is not as satisfactory as for neutrons.

The scattering of a composite particle off a nucleus with account of the breakup effect is solved via the original formalism of the stationary wave packets. The approach is based on the integral equation formalism of the scattering theory with a complete discretization of the three-body continuum. This allows one to find the elastic and breakup amplitudes from one nonsingular matrix equation and also to use a very convenient $L_2$ basis in numerical calculations. The efficiency of the approach is demonstrated by a realistic example of deuteron scattering on a ${}^{58}\mathrm{Ni}$ target.

The CELSIUS-WASA setup is used to measure the $3{\pi }^0$ decay of η mesons produced in $\mathit{pp}$ interactions with beam kinetic energies of 1.36 and 1.45 GeV. The efficiency-corrected Dalitz plot and density distributions for this decay are shown, together with a fit of the quadratic slope parameter α yielding $\alpha =-0.026\pm 0.010(\mathrm{stat})\pm 0.010(\mathrm{syst})$. This value is compared to recent experimental results and theoretical predictions.

$\Lambda$-hypernuclei single-particle energies are calculated for the new Nijmegen ESC04 baryon-baryon interaction. A Brueckner-Hartree approach is employed. Whereas good agreement with experimental results is obtained for the $A=3,4$, and 5 systems, the heavier systems are considerably overbound. A possible source for some of the overbinding is the spin-orbit odd interaction and its effect on the ${}^3{\mathrm{P}}_2$ channel.

We analyze the Coulomb breakup cross sections of ${}^{11}\mathrm{Li}$ and ${}^6\mathrm{He}$ nuclei using a three-body model with a density-dependent contact interaction. We show that the concentration of the $B(E1)$ strength near the threshold can be well reproduced with this model. With the help of the calculated $B(E1)$ value, we extract the root-mean-square (rms) distance between the core nucleus and the center-of-mass of two valence neutrons without resorting to the sum rule, which may suffer from unphysical Pauli forbidden transitions. Together with the empirical rms distance between the neutrons obtained from the matter radius study and also from the three-body correlation study in the breakup reaction, we convert these rms distances to the mean opening angle between the valence neutrons from the core nucleus. We find that the obtained mean opening angles in ${}^{11}\mathrm{Li}$ and ${}^6\mathrm{He}$ agree with the three-body model predictions.

A previously unreported isomer has been identified in ${}^{99}\mathrm{Mo}$ at an excitation energy of $E_x=3010$ keV, decaying with a half-life of $T_{1/2}=8(2)$ ns. The nucleus of interest was produced following fusion-fission reactions between a thick ${}^{27}\mathrm{Al}$ target frame and a ${}^{178}\mathrm{Hf}$ beam at a laboratory energy of 1150 MeV. This isomeric state is interpreted as an energetically favored, maximally aligned configuration of $\nu h_{\frac{11}{2}}\otimes \pi (g_{\frac{9}{2}}){}^2$.

Hindrance factors corresponding to α decay from two quasiparticle isomeric high $K$ states are evaluated in superheavy nuclei. We found that the hindrance factors are very sensitive to the deformations and, therefore, they may constitute a powerful tool to extract spectroscopic information in these nuclei. The hindrance factors turn out to be very large, specially for nonaligned configurations. This indicates that if one of such states is reached the parent nucleus may become isomeric. It is also possible that α decay may not proceed through ground state to ground state chains but rather through excited states.

The isospin dependence of incompressibility is investigated in Skyrme Hartree-Fock (SHF) and relativistic mean field (RMF) models. The correlations between the nuclear matter incompressibility and the isospin-dependent term of the finite nucleus incompressibility is elucidated using the Thomas-Fermi approximation. The Coulomb term is also studied by using various different Skyrme Hamiltonians and RMF Lagrangians. Microscopic $\mathrm{HF}+\mathrm{random}$ phase approximation (RPA) calculations are performed with Skyrme interactions for ${}^{208}\mathrm{Pb}$ and Sn isotopes to study the strength distributions of isoscalar giant monopole resonances. The symmetry term of nuclear incompressibility is extracted to be $K_{\tau }=-(500\pm 50)$ MeV from the recent experimental data of isoscalar giant monopole resonances (ISGMR) in Sn isotopes.

We investigate the role of short-range correlations in quark matter within the framework of the SU(2) Nambu–Jona-Lasinio model. Employing a next-to-leading order expansion in $1/N_c$ for the quark self-energy, we construct a fully self-consistent model that is based on the relations between spectral functions and self-energies. In contrast to the usual quasiparticle approximations, we take the collisional broadening of the quark spectral function consistently into account. Mesons are dynamically generated in the fashion of a random phase approximation, using full in-medium propagators in the quark loops. The results are self-consistently fed back into the quark self-energy. Calculations have been performed for finite chemical potentials at zero temperature. The short-range correlations not only generate finite widths in the spectral functions but also have influence on the chiral phase transition.

Starting from the microscopic low-momentum nucleon-nucleon interaction $V_{\mathrm{low}k}$, we present a systematic shell-model study of magnetic moments and magnetic dipole transition strengths of the basic low-energy one-quadrupole phonon excitations in nearly spherical nuclei. Studying in particular the even-even $N=52$ isotones from ${}^{92}\mathrm{Zr}$ to ${}^{100}\mathrm{Cd}$, we find the predicted evolution of the predominantly proton-neutron nonsymmetric state reveals a restoration of collective proton-neutron mixed-symmetry structure near midshell. This provides a quantitative explanation for the existence of pronounced collective mixed-symmetry structures in weakly collective nuclei.

We show that the ground-state band spectra of very many rare-earth and actinide nuclei appear to obey simple recurrence relations. Our initial empirical observation is then refined to suggest a new method for predicting higher lying members of a band from lower lying known members.

In Hanbury-Brown–Twiss interferometry measurements using identical bosons, the chaoticity parameter λ has been introduced phenomenologically to represent the momentum correlation function at zero relative momentum. It is useful to study an exactly solvable problem in which the λ parameter and its dependence on the coherence properties of the boson system can be worked out in great detail. We are therefore motivated to study the state of a gas of noninteracting identical bosons at various temperatures held together in a harmonic oscillator potential that arises either externally or from bosons’ own mean fields. We determine the degree of Bose-Einstein condensation and its momentum correlation function as a function of the attributes of the boson environment. The parameter λ can then be evaluated from the momentum correlation function. We find that the $\lambda (p,T)$ parameter is a sensitive function of both the average pair momentum $p$ and the temperature $T$, and the occurrence of $\lambda =1$ is not a consistent measure of the absence of a coherent condensate fraction. In particular, for large values of $p$, the λ parameter attains the value of unity even for significantly coherent systems with large condensate fractions. We find that if a pion system maintains a static equilibrium within its mean field, and if it contains a root-mean-squared radius, a pion number, and a temperature typical of those in high-energy heavy-ion collisions, then it will contain a large fraction of the Bose-Einstein pion condensate.

Muon capture $\gamma$ rays have been observed for the first time in ${}^{27}\mathrm{Al}$, and a significant improvement has been made in the identification of γ-rays from muon capture in natural Si. The (${\mu }^{-},\nu \gamma$) reaction was clearly observed in both nuclei and, for ${}^{28}\mathrm{Si}$, compares well with calculations. The (${\mu }^{-},\nu n\gamma$) reaction was also observed strongly in both nuclei, and the levels which are excited correlate fairly well with the ($\gamma ,p$) reaction, but not as well with the spectroscopic factors from the ($d$, ${}^3\mathrm{He}$) reaction. Some (${\mu }^{-},\nu 2n\gamma$), (${\mu }^{-},\nu 3n\gamma$), (${\mu }^{-},\nu p\gamma$), (${\mu }^{-},\nu \mathit{pn}\gamma$), and other reactions have been observed at a lower yield. The Lyman series of the muonic x ray cascades have also been studied.