Cross sections for direct and resonant breakup of radioactive ${}^7\mathrm{Be}$ nuclei produced in a transfer reaction ${}^{112}\mathrm{Sn}({}^6\mathrm{Li},{}^7\mathrm{Be}\to \alpha +{}^3\mathrm{He}){}^{111}\mathrm{In}$ have been measured. Breakup of ${}^7\mathrm{Be}$ into $\alpha$ and ${}^3\mathrm{He}$ cluster fragments via its resonant states of $7/2^{-}$(4.57 MeV) and $5/2^{-}$ (6.73 MeV) in the continuum have been identified for the first time using the measured distribution of $\alpha \text{−}{}^3\mathrm{He}$ relative energy and the reaction $Q$ value obtained from the $\alpha \text{−}{}^3\mathrm{He}$ coincident events. The breakup cross sections extracted from the efficiency corrected coincidence yield compares well with the results of the coupled-channels calculations. Significant cross sections for breakup of ${}^7\mathrm{Be}$ into its cluster fragments directly or through resonant states highlight the importance of the ground-state structure of ${}^7\mathrm{Be}$ as a cluster of $\alpha$ and ${}^3\mathrm{He}$.

We investigate the hadron production from the vortical quark-gluon plasma created in heavy-ion collisions. Based on the quark-coalescence and statistical hadronization models, we show that total hadron yields summed over the spin components are enhanced by the local vorticity with quadratic dependence. The enhancement factor amounts to be a few percent and may be detectable within current experimental sensitivities. We also show that the effect is stronger for hadrons with larger spin, and thus propose a new signature of the local vorticity, which may be detected by the yield ratio of distinct hadron species having different spins such as $\varphi$ and ${\eta }^{\prime }$. The vorticity dependence of hadron yields seems robust, with consistent predictions in both of the hadron production mechanisms for reasonable values of the vorticity strength estimated for heavy-ion collisions.

$\beta$-decay spectroscopy of ${}^{173,174}\mathrm{Ho}$ ($Z$ $=$ 67, $N$ $=$ 106,107) was conducted at Radioactive Isotope Beam Factory at RIKEN by using in-flight fission of a 345-MeV/u ${}^{238}\mathrm{U}$ primary beam. A previously unreported isomeric state at 405 keV with half-life of 3.7(12) $\mu \mathrm{s}$ and a spin and parity of ($3/2^{+}$) is identified in ${}^{173}\mathrm{Ho}$. Moreover, a new state with a spin and parity of $9^{-}$ was discovered in ${}^{174}\mathrm{Er}$. The experimental log ft values of 5.84(20) and 5.25(18) suggest an allowed-hindered $\beta$ decay from the ground state of ${}^{174}\mathrm{Ho}$ to the ${\mathrm{K}}^{\pi }=8^{-}$ isomeric state in ${}^{174}\mathrm{Er}$. Configuration-constrained potential energy surface (PES) calculations were performed and the predictions are in reasonable agreement with the experimental results.

In this paper we revisit mass relations of mirror nuclei by considering the odd-even feature in Coulomb energy. A substantial improvement and competitive accuracy of mass relations is achieved, with root-mean-squared deviations (RMSD) of only 93 keV; for the first time one is able to construct simple mass formulas for mirror nuclei with the RMSD below 100 keV in light- and medium-mass regions (mass number $A=20$–90) by using only four parameters. As a by-product we tabulate our predictions of masses excesses unaccessible experimentally in the Supplemental Material of this paper.

Average matrix elements of ordinary muon capture (OMC) to the intermediate nuclei of neutrinoless double beta ($0\nu \beta \beta$) decays of current experimental interest are computed and compared with the corresponding energy and multipole decompositions of $0\nu \beta \beta$-decay nuclear matrix elements (NMEs). The present OMC computations are performed using the Morita-Fujii formalism by extending the original formalism beyond the leading order. The $0\nu \beta \beta$ NMEs include the appropriate short-range correlations, nuclear form factors, and higher-order nucleonic weak currents. The nuclear wave functions are obtained in extended no-core single-particle model spaces using the spherical version of the proton-neutron quasiparticle random-phase approximation with two-nucleon interactions based on the Bonn one-boson-exchange $G$ matrix. Both the OMC and $0\nu \beta \beta$ processes involve 100-MeV-range momentum exchanges and hence similarities could be expected for both processes in the feeding of the $0\nu \beta \beta$ intermediate states. These similarities may help improve the accuracy of the $0\nu \beta \beta$ NME calculations by using the data from the currently planned OMC experiments.

The nucleon pair shell model (NPSM) is cast into the so-called $M$ scheme for the cases with isospin symmetry and without isospin symmetry. The odd system and even system are treated on the same footing. The uncoupled commutators for nucleon pairs, which are suitable for the $M$ scheme, are given. Explicit formula of matrix elements in $M$ scheme for overlap, one-body operators, and two-body operators are obtained. It is found that the CPU time used in calculating the matrix elements in $M$ scheme is much shorter than that in the $J$ scheme of NPSM.

We present results of an updated calculation of the two particle two hole (2p2h) contribution to the neutrino-induced charge-current cross section. We provide also some exclusive observables, interesting from the point of view of experimental studies, e.g., distributions of momenta of the outgoing nucleons and of available energy, which we compare with the results obtained within the NEUT generator. We also compute, and separate from the total, the contributions of 3p3h mechanisms. Finally, we discuss the differences between the present results and previous implementations of the model in MC event generators, done at the level of inclusive cross sections, which might significantly influence the experimental analyses, particularly in the cases where the hadronic observables are considered.

Preliminary data by the STAR collaboration at the BNL Relativistic Heavy Ion Collider shows that the elliptic flow, $v_2$, and the average transverse momentum, $\langle p_t\rangle$, of final-state hadrons produced in high-multiplicity ${}^{238}\mathrm{U}+{}^{238}\mathrm{U}$ collisions are negatively correlated. This observation brings experimental evidence of a significant prolate deformation, $\beta \approx 0.3$, in the colliding ${}^{238}\mathrm{U}$ nuclei. I show that a quantitative description of this new phenomenon can be achieved within the hydrodynamic framework of heavy-ion collisions, and that thus such kind of data in the context of high-energy nuclear experiments can help constrain the quadrupole deformation of the colliding species.

For the reaction $\gamma p\to \omega p$, differential cross sections, photon beam asymmetries, and spin density matrix elements have been measured in the BGOegg experiment at the SPring-8 LEPS2 beamline by using a large acceptance electromagnetic calorimeter. A 1.3–2.4 GeV photon beam with high linear polarization has enabled a precision measurement of photon beam asymmetries $\mathrm{\Sigma }$ and polarized spin density matrix elements ${\rho }_{1-1}^1$ over a wide angular range, especially above the total energy of about 2 GeV for the first time. The measured ${\rho }_{1-1}^1$ indicates the dominance of $s$-channel resonances even at higher energies. The $\mathrm{\Sigma }$ values at backward angles are not reproduced by the existing partial-wave analysis in the highest-energy region, providing new constraints to the contribution of nucleon resonances with high spins.

We present a determination of optical potentials using the double-folding method based on chiral effective field theory nucleon-nucleon interactions at next-to-next-to-leading order combined with dispersion relations to constrain the imaginary part. This approach is benchmarked on ${}^{16}\mathrm{O}-{}^{16}\mathrm{O}$ collisions, and extended to the ${}^{12}\mathrm{C}-{}^{12}\mathrm{C}$ and ${}^{12}\mathrm{C}-{}^{16}\mathrm{O}$ cases. Predictions derived from these potentials are compared to data for elastic scattering at energies up to 1000 MeV, as well as for fusion at low energy. Without adjusting parameters, excellent agreement with experiment is found. In addition, we study the sensitivity of the corresponding cross sections to the nucleon-nucleon interactions and nuclear densities used.

The ${\beta }^{-}$ decay of ${}^{81}\mathrm{Zn}$ to the neutron magic $N=50$ nucleus ${}^{81}\mathrm{Ga}$, with only three valence protons with respect to ${}^{78}\mathrm{Ni}$, was investigated. The study was performed at the ISOLDE facility at CERN by means of $\gamma$ spectroscopy. The ${}^{81}\mathrm{Zn}$ half-life was determined to be $T_{1/2}=290\left(4\right)$ ms while the $\beta$-delayed neutron emission probability was measured as $P_n=23\left(4\right)\%$. The analysis of the $\beta$-gated $\gamma$-ray singles and $\gamma \text{−}\gamma$ coincidences from the decay of ${}^{81}\mathrm{Zn}$ provides 47 new levels and 70 new transitions in ${}^{81}\mathrm{Ga}$. The ${\beta }^{-}n$ decay of ${}^{81}\mathrm{Zn}$ was observed and a new decay scheme into the odd-odd ${}^{80}\mathrm{Ga}$ nucleus was established. The half-lives of the first and second excited states of ${}^{81}\mathrm{Ga}$ were measured via the fast-timing method using ${\mathrm{LaBr}}_3$(Ce) detectors. The level scheme and transition rates are compared to large-scale shell-model calculations. The low-lying structure of ${}^{81}\mathrm{Ga}$ is interpreted in terms of the coupling of the three valence protons outside the doubly magic ${}^{78}\mathrm{Ni}$ core.

Within the framework of the dinuclear system model, the reaction mechanism for producing the proton-rich actinide isotopes $Z=93–100$ near the proton drip line is thoroughly investigated in the fusion reactions with ${}^{24}\mathrm{Mg}, {}^{28}\mathrm{Si}, {}^{32}\mathrm{S}, {}^{36,40}\mathrm{Ar}$, and ${}^{40}\mathrm{Ca}$ bombarding the target nuclei ${}^{181}\mathrm{Ta}, {}^{180}\mathrm{W}, {}^{185}\mathrm{Re}, {}^{184}\mathrm{Os}, {}^{191}\mathrm{Ir}, {}^{190}\mathrm{Pt}, {}^{197}\mathrm{Au}, {}^{196}\mathrm{Hg}, {}^{203}\mathrm{Tl}, {}^{204}\mathrm{Pb}$, and ${}^{209}\mathrm{Bi}$, and in the multinucleon transfer reactions with proton-rich radioactive beams ${}^{59}\mathrm{Cu}, {}^{69}\mathrm{As}, {}^{90}\mathrm{Nb}, {}^{91}\mathrm{Tc}, {}^{94}\mathrm{Rh}, {}^{105,110}\mathrm{Sn}$, and ${}^{118}\mathrm{Xe}$ on ${}^{238}\mathrm{U}$ near Coulomb barrier energies. The production cross sections of new proton-rich isotopes in the fusion-evaporation reactions and fragment yields in the multinucleon transfer reactions are estimated systematically and compared in both reaction mechanisms, in which a statistical approach is used to describe the decay process of excited nuclei. A dynamical deformation is implemented in the model in the dissipation process. It is found that charged particle evaporation channels (alpha and proton) dominate in the decay process of proton-rich nuclides. The fusion-evaporation reactions are favorable to produce the new neutron-deficient actinide isotopes. The total kinetic energies and angular spectra of primary fragments in multinucleon transfer reactions are strongly dependent on colliding orientations and incident energies.

We show that the experimental data of transverse momentum ($p_T$) spectra of $\mathrm{\Omega }$ baryon and $\varphi$ meson at midrapidity in heavy-ion collisions exhibit the constituent quark number scaling in a wide energy range from the Relativistic Heavy Ion Collider to the Large Hadron Collider. Such a scaling behavior is a direct consequence of quark combination mechanism via equal velocity combination and provides a very convenient way to extract the $p_T$ spectrum of strange quarks at hadronization. We present the results of strange quarks obtained from the available data and study the properties in particular the energy dependence of the averaged transverse momentum $\langle p_T\rangle$ and the transverse radial flow velocity $\langle \beta \rangle$ with a hydrodynamics-motivated blast-wave model.

The strange quark contributions to the electromagnetic form factors of the proton are ideal quantities to study the role of hidden flavor in the properties of the proton. This has motivated intense experimental measurements of these form factors. A major remaining source of systematic uncertainty in these determinations is the assumption that charge symmetry violation (CSV) is negligible. We use recent theoretical determinations of the CSV form factors and reanalyze the available parity-violating electron scattering data, up to $Q^2\approx 1 {\mathrm{GeV}}^2$. Our analysis considers systematic expansions of the strangeness electric and magnetic form factors of the proton. The results provide an update to the determination of strangeness over a range of $Q^2$ where, under certain assumptions about the effective axial form factor, an emergence of nonzero strangeness is revealed in the vicinity of $Q^2\approx 0.6{\mathrm{GeV}}^2$. Given the recent theoretical calculations, it is found that the current limits on CSV do not have a significant impact on the interpretation of the measurements and hence suggests an opportunity for a next generation of parity-violating measurements to more precisely map the distribution of strange quarks.

Using the Gribov-Glauber model for photon-nucleus scattering and a generalization of the vector meson dominance model for the hadronic structure of the photon, we make predictions for the cross section of incoherent $\rho$ photoproduction in Pb-Pb ultraperipheral collisions in the Large Hadron Collider kinematics. We find that the effect of the inelastic nuclear shadowing is significant and leads to an additional 25% suppression of the incoherent cross section. Comparing our predictions to those of the STARlight Monte Carlo framework, we observe very significant differences.

Neutrino telescopes like IceCube, KM3NeT, and Baikal-GVD offer physicists the opportunity to study neutrinos with energies far beyond the reach of terrestrial accelerators. These neutrinos are used to study high-energy neutrino interactions and to probe the Earth through absorption tomography. Current studies of TeV neutrinos use cross sections which are calculated for free nucleons with targets which are assumed to contain equal numbers of protons and neutrons. Here we consider modifications of high-energy neutrino interactions due to two nuclear effects: modifications of the parton densities in the nucleus, referred to here as shadowing, and the effect of nonisoscalar targets, with unequal numbers of neutrons and protons. Both of these effects depend on the interaction medium. Because shadowing is larger for heavier nuclei, such as iron, found in the Earth's core, it introduces a zenith-angle dependent change in the absorption cross section. These modifications increase the cross sections by 1–2% at energies below 100 TeV (antishadowing) and reduce it by 3–4% at higher energies (shadowing). Nuclear effects also alter the inelasticity distribution of neutrino interactions in water/ice by increasing the number of low-inelasticity interactions, with a larger effect for $\nu$ than $\overline{\nu }$. These effects are particularly large in the energy range below a few TeV. These effects could alter the cross sections inferred from events with tracks originating within the active detector volume as well as the ratio $\nu /\overline{\nu }$ inferred from inelasticity measurements. The uncertainties in these nuclear effects are larger than the uncertainties on the free-proton cross sections and will thus limit the systematic precision of future high-precision measurements at neutrino telescopes.

This article reports on results of an experimental search for ground state shell inversion in the neutron-unbound $N=7$ isotones ${}^9\mathrm{He}$ and ${}^{10}\mathrm{Li}$. Two different radioactive ion beams (${}^{11}\mathrm{Be}$, $E_{\mathrm{lab}}=44\mathrm{MeV}$/u and ${}^{12}\mathrm{B}$, $E_{\mathrm{lab}}=45\mathrm{MeV}$/u) impinging on a beryllium target were used to directly and selectively populate unbound states of a given $\ell$ in the nuclides of interest. $\mathrm{Be}({}^{11}\mathrm{Be},{}^8\mathrm{He}+n)$ and $\mathrm{Be}({}^{12}\mathrm{B},{}^8\mathrm{He}+n)$ reactions populated unbound states in ${}^9\mathrm{He}$. Fragments and neutrons were detected in coincidence to reconstruct the decay energy of ${}^9\mathrm{He}$ using invariant mass spectroscopy. Similarly, $\mathrm{Be}({}^{11}\mathrm{Be},{}^9\mathrm{Li}+n)$ and $\mathrm{Be}({}^{12}\mathrm{B},{}^9\mathrm{Li}+n)$ reactions were used to populate unbound states in ${}^{10}\mathrm{Li}$, and the time-of-flight method was used to determine the relative velocity of the ${}^9\mathrm{Li}$ fragments and neutrons in coincidence. Various states in both ${}^9\mathrm{He}$ and ${}^{10}\mathrm{Li}$ were observed and characterized. The data indicate possible ground state shell inversion in both cases.

Background: The $Z=50$ shell closure, near $N=82$, is unique in the sense that it is the only shell closure with the spin-orbit partner orbitals, $\pi g_{9/2}$ and $\pi g_{7/2}$, enclosing the magic gap. The interaction of the proton hole/particle in the above-mentioned orbitals with neutrons in the $\nu h_{11/2}$ orbital is an important prerequisite to the understanding of the nuclear structure near $N=82$ and the $\nu \pi$ interaction.

Purpose: To explore the structural similarity between the high-spin isomeric states in In ($Z=49$), Sn ($Z=50$), and Sb ($Z=51$) isotopes from a microscopic point of view. In addition, to understand the role of a proton hole or particle in the spin-orbit partner orbitals, $\pi g_{9/2}$ and $\pi g_{7/2}$, respectively, with neutron holes in the $\nu h_{11/2}$ orbital on these aforementioned isomers.

Methods: The fusion and transfer induced fission reaction ${}^9\mathrm{Be}({}^{238}\mathrm{U}, f)$ with 6.2 MeV/u beam energy, using a unique setup consisting of AGATA, $\mathrm{VAMOS}++$, and EXOGAM detectors, was used to populate through the fission process and study the neutron-rich ${}^{119,121}\mathrm{In}$ isotopes. This setup enabled the prompt-delayed $\gamma$-ray spectroscopy of isotopes in the time range of $100\mathrm{ns}–200\mu \mathrm{s}$.

Results: In the odd-$A{}^{119,121}\mathrm{In}$ isotopes, indications of a short half-life $19/2^{-}$ isomeric state, in addition to the previously known $25/2^{+}$ isomeric state, were observed from the present data. Further, new prompt transitions above the $25/2^{+}$ isomer in ${}^{121}\mathrm{In}$ were identified along with reevaluation of its half-life.

Conclusions: The experimental data were compared with the theoretical results obtained in the framework of large-scale shell-model calculations in a restricted model space. The $\langle \pi g_{9/2}\nu h_{11/2};I\left|\widehat{\mathcal{H}}\right|\pi g_{9/2}\nu h_{11/2};I\rangle$ two-body matrix elements of residual interaction were modified to explain the excitation energies and the $B\left(E2\right)$ transition probabilities in the neutron-rich In isotopes. The (i) decreasing trend of $E(29/2^{+})–E(25/2^{+})$ in odd-In (with dominant configuration $\pi g_{9/2}^{-1}\nu h_{11/2}^{-2}$ and maximum aligned spin of $29/2^{+}$) and (ii) increasing trend of $E(27/2^{+})-E(23/2^{+})$ in odd-Sb (with dominant configuration $\pi g_{7/2}^{+1}\nu h_{11/2}^{-2}$ and maximum aligned spin of $27/2^{+}$) with increasing neutron number could be understood as a consequence of hole-hole and particle-hole interactions, respectively.

We approximate the realistic $\alpha$-core nuclear interaction between the inner turning point and Coulomb barrier, derived within the double folding procedure, by a parabolic dependence. It turns out that the corresponding harmonic oscillator frequency is concentrated in a narrow interval around $\hslash {\omega }_1\approx$ 9 MeV for all analyzed transitions from even-even and odd-mass $\alpha$ emitters. The penetrability through the nuclear barrier has an exponential dependence on the ratio between the fragmentation potential and this harmonic oscillator frequency. On the other hand, the Coulomb penetrability has the standard dependence on the Coulomb parameter. Our analysis revealed that the reduced width, extracted by using the nuclear plus Coulomb penetrability factors, exponentially decreases versus the number of $\alpha$ clusters along all analyzed $\alpha$ lines, except one region where it increases by approaching the neutron magic number $N_{\mathrm{mag}}=126$. In that case, the number of valence proton pairs is much smaller than the number of valence neutron pairs. The reduced width exponentially depends on the magic neutron-proton asymmetry above doubly magic nuclei. These dependencies allow us to propose a systematics for reduced widths in terms of the quartet number and magic asymmetry evaluated above the closest doubly magic nuclei.