Double-differential cross sections for light charged particle production (up to $A=4$) were measured in $96\mathrm{MeV}$ neutron-induced reactions, at the TSL Laboratory Cyclotron in Uppsala (Sweden). Measurements for three targets, $\mathrm{Fe}$, $\mathrm{Pb}$, and $\mathrm{U}$, were performed using two independent devices, SCANDAL and MEDLEY. The data were recorded with low-energy thresholds and for a wide angular range $\left(20°–160°\right)$. The normalization procedure used to extract the cross sections is based on the $np$ elastic scattering reaction that we measured and for which we present experimental results. A good control of the systematic uncertainties affecting the results is achieved. Calculations using the exciton model are reported. Two different theoretical approaches proposed to improve its predictive power regarding the complex particle emission are tested. The capabilities of each approach is illustrated by comparison with the $96\mathrm{MeV}$ data that we measured, and with other experimental results available in the literature.

The alpha-particle spectra and the proton spectra at different laboratory angles from the fusion reactions ${}^{16}\mathrm{O}+{}^{64}\mathrm{Zn}$ at $95\mathrm{Mev}$ and ${}^{32}\mathrm{S}+{}^{48}\mathrm{Ti}$ at $125\mathrm{MeV}$ were measured. Both systems have zero channel spin and lead to the compound nucleus ${}^{80}{\mathrm{Sr}}^{*}$ with the same value of $l_{\max }=43\hslash$. The observed spectra from the asymmetric reaction ${}^{16}\mathrm{O}+{}^{64}\mathrm{Zn}$ reaction can be reproduced with the statistical model calculations using rotating liquid drop model values of moment of inertia and transmission coefficients for spherical nuclei. However, the charged particle spectra in case of the symmetric ${}^{32}\mathrm{S}+{}^{48}\mathrm{Ti}$ reaction are not in agreement with the predictions of the statistical model. In order to explain the experimental spectra for the ${}^{32}\mathrm{S}+{}^{48}\mathrm{Ti}$ reaction, the analysis was done using the dynamical model of Feldmeier et al. [Rep. Prog. Phys. 50, 915 (1987)]. This analysis shows that the effective $l_{\max }$ value for fusion to take place in the case of the symmetric system is lowered to $30\hslash$. The statistical model calculations for the dynamical model predicted the $l_{\max }$ value reproduced the observed spectra reasonably well indicating entrance channel effects on the decay of the compound nucleus.

Atomic masses of radioactive zirconium isotopes from ${}^{96}\mathrm{Zr}$ to ${}^{104}\mathrm{Zr}$ have been measured with a relative accuracy of $⩽5\times {10}^{-7}$ using a Penning trap coupled to the ion guide isotope separator on-line system. The obtained two-neutron separation energies show strong local correlation in relation to the shape change and shape coexistence between $N=58$ and 60.

A solution of the Bohr collective Hamiltonian for the $\beta$-soft, $\gamma$-soft triaxial rotor with $\gamma \sim \pi ∕6$ is presented making use of a harmonic potential in $\gamma$ and Coulomb-like and Kratzer-like potentials in $\beta$. It is shown that, while the $\gamma$-angular part in the present case gives rise to a straightforward extension of the rigid triaxial rotor energy in which an additive harmonic term appears, the inclusion of the $\beta$ part results instead in a nontrivial expression for the spectrum. The negative anharmonicities of the energy levels with respect to a simple rigid model are in qualitative agreement with general trends in the experimental data.

The mechanism is studied which causes an anomalous magnetic moment of ${}^9\mathrm{C}$, i.e., too large isoscalar spin for the $T_z=\pm 3∕2$ mirror pair of $A=9$, from a shell-model viewpoint. Based on the empirically determined shell energies varying from stable to unstable nuclei, the effective $N=8$ shell gap for $Z=3$ is evaluated to be rather narrow in a reasonable way. Under this condition, an additional shell quenching by the Thomas-Ehrman effect, arising for ${}^9\mathrm{C}$ only, allows its ground state to be substantially mixed with the intruder configurations. This mirror asymmetry in the mirror wave functions accounts for the obviously large spin expectation value.

The effect of correlated scalar-isoscalar two-pion exchange (CrTPE) modes is considered in connection with central and spin-orbit parts of the nucleon-nucleon $\left(NN\right)$ force. The two-pion correlation function is coupled directly to the scalar form factor of the nucleon which we calculate in the large-$N_c$ limit where the nucleon can be described as a soliton of an effective chiral theory. The results for the central $NN$ force show a strong repulsive core at short internucleon distances supplemented by a moderate attraction beyond $1\mathrm{fm}$. The long-range tail of the central $NN$ potential is driven by the pion-nucleon sigma term and consistent with the effective $\sigma$ meson exchange. The spin-orbit part of the $NN$ potential is repulsive. The large-$N_c$ scaling behavior of the scalar-isoscalar $NN$ interaction is addressed. We show that the spin-orbit part is $\mathcal{O}(1∕N_c^2)$ in strength relative to the central force resulting in the ratio $\simeq 1∕9$ suggested by the $1∕N_c$ expansion for $N_c=3$. The latter is in agreement with our numerical analysis and with the Kaplan-Manohar large-$N_c$ power counting. Unitarization of the $\pi \pi$ scattering amplitude plays here an important role and improves the tree level results. Analytical representations of the CrTPE $NN$ potential in terms of elementary functions are derived and their chiral content is discussed.

We analyze cross sections for quasielastic inclusive scattering of electrons on nuclei and show that the observed isolated peaks for relatively low $Q^2$ are unique for the lightest targets. Focusing, in particular, on D and ${}^4\mathrm{He}$, we investigate in two ways to what measure the above peaks can be allocated to nucleon-elastic processes. We first compute approximate upper limits for the nucleon-inelastic background in the quasielastic region due to inclusive $\Delta$ excitation, and find those to be small. Far more precise is a semiphenomenological approach, where the dominance of nucleon-elastic processes is translated into a set of stringent requirements. We show that those are very well fulfilled for recent D data, and to a somewhat lesser extent for older D and ${}^4\mathrm{He}$ data. With knowledge of $G_{E,M}^p$ and information on $G_E^n$, we then extract $G_M^n$ and find agreement with values obtained by alternative methods. We discuss the sensitivity of the extraction method and mention future applications.

The giant resonance region from $10\mathrm{MeV}<E_x<55\mathrm{MeV}$ in ${}^{112}\mathrm{Sn}$ and ${}^{124}\mathrm{Sn}$ has been studied with inelastic scattering of $240\mathrm{MeV}$ $\alpha$ particles at small angles including 0°. Essentially, all of the expected isoscalar $E0–E3$ strength was located in both nuclei. The isotopic dependence of the giant monopole resonance energies was found to be consistent with relativistic and nonrelativistic calculations for interactions with $K_{\mathrm{NM}}\sim 220–240\mathrm{MeV}$.

An analysis of the quasielastic and inelastic peaks of neutrons induced by $1.2\mathrm{GeV}$ protons on targets with $27⩽A⩽232$ is presented using the ultrarelativistic quantum molecular dynamics (UrQMD) model. Two distinct contributions of the nuclear medium are studied in the UrQMD framework, referred to as “in-medium” and “mean field” effects. The former only includes modifications to the $NN$-elastic and $NN\to N\Delta$ angular distributions as well as changes to the $\Delta$-mass distribution. The latter incorporates the (QMD) interaction potential between nucleons. It is shown that in-medium effect produces an important role for enhancing the quasi-inelastic peak, while the mean field effect enhances the intensity of both peaks and becomes important in the quasielastic region. The introduction of both effects in the UrQMD calculations improves the intensity and location of the quasielastic and inelastic peaks. A rather smooth dependence of the integrated cross sections of the quasielastic and inelastic peaks on the mass number at both angles is also found and shown to be in qualitative agreement with the UrQMD incorporating these two effects.

Calculations of the ${}^{16}\mathrm{O}\left(e,e^{\prime }pN\right)$ cross sections to the ground state and first excited levels of the ${}^{14}\mathrm{C}$ and ${}^{14}\mathrm{N}$ nuclei are presented. The effects of nuclear fragmentation have been obtained in a self-consistent approach and are accounted for in the determination of the two-nucleon removal amplitudes. The Hilbert space is partitioned in order to compute the contribution of both long- and short-range effects in a separate way. Both the two-proton and the proton-neutron emission cross sections have been computed within the same model for the nuclear structure as well as the same treatment of the reaction mechanism, with the aim of better comparing the differences between the two physical processes. The ${}^{16}\mathrm{O}\left(e,e^{\prime }pp\right)$ reaction is found to be sensitive to short-range correlations, in agreement with previous results. The ${}^{16}\mathrm{O}\left(e,e^{\prime }pn\right)$ cross section to $1^{+}$ final states is dominated by the $\Delta$ current and tensor correlations. For both reactions, the interplay between collective (long-range) effects and short-range and tensor correlations plays an important role. This suggests that the selectivity of $(e,e^{\prime }pN)$ reactions to the final state can be used to probe correlations also beyond short-range effects.

The $\alpha +{}^6\mathrm{He}$ decay of ${}^{10}\mathrm{Be}$ has been studied via the ${}^7\mathrm{Li}\left({}^7\mathrm{Li},\alpha {}^6\mathrm{He}\right)\alpha$ reaction at $58\mathrm{MeV}$. The excitation energy of the ${}^{10}\mathrm{Be}$ nucleus was determined following the coincident detection of the $\alpha$ and ${}^6\mathrm{He}$ decay products. A study of the fragment angular correlations has provided a spin assignment consistent with the previously reported value of $3^{-}$ for the $10.15\mathrm{MeV}$ state in ${}^{10}\mathrm{Be}$. A tentative assignment of $\left(4^{+}\right)$, $6^{+}$ is proposed for the $11.76\mathrm{MeV}$ state.

The level scheme of ${}^{51}\mathrm{Mn}$ has been investigated using the ${}^{28}\mathrm{Si}({}^{32}\mathrm{S},2\alpha 1p){}^{51}\mathrm{Mn}$ fusion-evaporation reaction at $125\mathrm{MeV}$ beam energy. The $\gamma$ rays were detected in the Ge-detector array Gammasphere, which was coupled to the $4\pi$-charged-particle detector Microball and the Neutron Shell for the coincident detection of evaporated particles. Over 100 new $\gamma$-ray transitions connecting some 50 excited states have been identified. Most of the states are built on particle-hole excitations across the shell gaps at particle number $N=Z=28$. The rich experimental data allows for a comprehensive comparison of core-excited states with results from large-scale shell-model calculations, which are known to provide excellent predictions for the lower-lying yrast and near-yrast levels in $1f_{7∕2}$ nuclei.

We study the thermodynamics of the linear sigma model with constituent quarks beyond the mean-field approximation. By integrating out the quark degrees of freedom we derive an effective action for the meson fields which is then linearized around the ground state including field fluctuations. We propose a new method for performing exact averaging of complicated functions over the meson field fluctuations. Both thermal and zero-point fluctuations are considered. The chiral condensate and the effective meson masses are determined self-consistently in a rigorous thermodynamic framework. At zero chemical potential the model predicts a chiral crossover transition which separates two distinct regimes: heavy quarks and light pions at low temperatures, but light quarks and heavy mesons at high temperatures. The crossover becomes a first order phase transition if the vacuum pion mass is reduced from its physical value.

The deuteron-to-proton polarization-transfer coefficients for $d\text{−}p$ elastic scattering were precisely measured with an incoming deuteron energy of $135\mathrm{MeV}∕\mathrm{\text{nucleon}}$ at the RIKEN Accelerator Research Facility. The data are compared to theoretical predictions based on exact solutions of the three-nucleon Faddeev equations with high-precision nucleon-nucleon forces combined with the current, most popular three-nucleon force (3NF) models: the $2\pi$-exchange Tucson-Melbourne model, a modification thereof based on chiral symmetry, ${\mathrm{TM}}^{\prime }\left(99\right)$, and the Urbana IX 3NF. Theory predicts large 3NF effects, especially in the angular range around the cross section minimum, predominantly for $K_{xx}^{y^{\prime }}-K_{yy}^{y^{\prime }}\left(K_{xx}^{y^{\prime }},K_{yy}^{y^{\prime }}\right)$, but the present data only partially concurs with the calculations. For the induced polarization, $P^{y^{\prime }}$, the ${\mathrm{TM}}^{\prime }\left(99\right)$ and Urbana IX 3NFs reproduce the data, but the Tucson-Melbourne 3NF fails to describe the data. For the polarization-transfer coefficients, $K_y^{y^{\prime }}$ and $K_{xz}^{y^{\prime }}$, the predicted 3NF effects are in drastic disagreement with the data. These facts clearly reveal the defects of the 3NF models currently used.

We present a systematics for the octupole and quadrupole deformation parameters of heavy nuclei. We also provide useful procedures to calculate the Coulomb and nuclear potentials for systems involving deformed nuclei.

A new semiempirical formula, with only three parameters, is proposed for cluster decay half-lives. The parameters of the formula are obtained by making a least squares fit to the available experimental cluster-decay data. The calculated half-lives are compared with the results of the earlier proposed model-independent scaling law and the empirically fitted analytical super-asymmetric fission model (ASAFM), showing more closeness to the ASAFM results.

In this paper we present all-order quantum mechanical calculations of ${}^7\mathrm{Be}$ breakup on heavy $\left({}^{208}\mathrm{Pb}\right)$ and light $\left({}^{12}\mathrm{C}\right)$ targets. We examine the issues concerning the extraction of the astrophysical $S$-factor $S_{34}\left(0\right)$ from the breakup data. We discuss the interplay between Coulomb and nuclear breakup, and the importance of higher-order couplings on the cross section. We show that nuclear and Coulomb contributions are not separable using the standard angular selection criterion as nuclear breakup remains large for small scattering angles, even for the heavy target. However, by selecting an upper limit on the relative energy between the final fragments, the contribution from the nuclear breakup can be significantly reduced such that Coulomb breakup is the main reaction mechanism. We show that the extraction of the asymptotic normalization coefficient may require more careful consideration of the nuclear interior than previously used.

The process of nuclear fragmentation in interactions of $3.7A\mathrm{GeV}$ ${}^{24}\mathrm{Mg}$ nuclei with the different target nuclei in a nuclear emulsion have been investigated. The total charge distributions of nuclear fragments are well described by the predictions of the extended Glauber model. The multiplicity and charge distributions of fragments with $Z⩾5$ in quasinucleon target events are found to agree satisfactorily with the calculations of the bond percolation model. The fragmentation of the projectile nucleus depends strongly on the target mass. The probability of interactions without any projectile fragments with charges $Z>2$ is zero for a hydrogen target, but increases by increasing the mass of the target. The disruption of a projectile nucleus is more severe in interactions with the heavy target nuclei than with the light ones. The topology for the nuclear fragmentation channels in interactions of the different projectiles with the different components of emulsion nuclei in the energy range $3.7–200A\mathrm{GeV}$ was analyzed. The average multiplicities and the relative rates of nuclear fragmentation channels from the incident nuclei are almost the same for all projectiles at different energies, revealing that the modes of nuclear fragmentation are energy independent. The stripped processes with relativistic hydrogen and∕or helium fragments are the dominant in all projectiles. Helium fragments are the most frequent among the multiple charged fragments and the fractional yield of nuclear fragmentation channels without projectile fragments heavier than helium fragments is about $27\%$ of the total sample. The interactions in which the projectile nuclei break up into single charged particles only represent $\approx 14\%$ of the total sample and are mostly due to central collisions in which the majority of projectile nucleons have participated in the first stage of the collisions.

The existence of phase transitions from liquid to gas phases in asymmetric nuclear matter (ANM) is related with the instability regions which are limited by the spinodals. In this work we investigate the instabilities in ANM described within relativistic mean field hadron models, both with constant and density dependent couplings at zero and finite temperatures. In calculating the proton and neutron chemical potentials we have used an expansion in terms of Bessel functions that is convenient at low densities. The role of the isovector scalar $\delta$-meson is also investigated in the framework of relativistic mean field models and density dependent hadronic models. It is shown that the main differences occur at finite temperature and large isospin asymmetry close to the boundary of the instability regions.

In beam angle-integrated cross section measurements of the ${}^{89}\mathrm{Y}(p,\gamma ){}^{90}\mathrm{Zr}$ reaction were carried out at $E_p=1.7–4.8\mathrm{MeV}$ by using a $4\pi$ NaI(Tl) summing detector. The resulting cross sections were used to derive astrophysical $S$ factors as well as reaction rates. Cross sections, $S$ factors and reaction rates have also been calculated by means of the statistical model code MOST. A good agreement between theoretical predictions and experimental data was found.