The nucleon-quark mixed matter is defined in the Brueckner-Hartree-Fock framework, in which quark densities are determined by equilibrium conditions between nucleon and quark chemical potentials, and nucleon-quark interactions play critical roles for resulting equations of state (EoSs). The two models of EoSs are derived from the nucleon-quark mixed matter (NQMM): The NQMM-A EoSs are based on the simple assumption that nucleons and free quarks occupy their respective Fermi levels and their Fermi spheres overlap from each other. In NQMM-B EoSs, the quark Fermi repulsion effect is incorporated on the basis of quarkyonic matter, meaning that the nucleon Fermi levels are pushed up from the quark Fermi sphere by the Pauli exclusion principle. For the NQMM-A EoSs, the neutron-star mass-radius $\left(MR\right)$ curves are pushed up above the region of $M\sim 2.1M_{\odot }$ and $R_{2.1M_{\odot }}\sim 12.5$ km indicated by recent observations, as the $qN$ repulsions increase. For the NQMM-B EoSs, similar results are obtained by the combined contributions from the $qN$ repulsion and the quark Fermi repulsion. In both models of EoSs, the important roles of the $qN$ diquark exchange repulsions are demonstrated to reproduce reasonable values of $M_{\max }$ and $R_{2.1M_{\odot }}$.

Proton-deuteron elastic scattering is considered in the framework of momentum-space Faddeev equations with the screening method for the Coulomb interaction. It is shown how the interplay of the proton-proton Coulomb potential and the deuteron pole in the neutron-proton transition operator leads to coinciding singularities in the Faddeev equation. The coincidence of those singularities was not taken into account in a previous work [Witała et al., Eur. Phys. J. A 41, 369 (2009)], leading to a conjecture that no renormalization is needed. However, the coinciding singularities closely resemble those of the point deuteron-proton system, naturally suggesting that the renormalization of the scattering amplitude is needed in the unscreened Coulomb limit and can be performed conveniently in terms of the point deuteron-proton system.

The ${}^{18}\mathrm{Ne}(d,t){}^{17}\mathrm{Ne}$ and ${}^{18}\mathrm{Ne}(d,{}^3\mathrm{He}){}^{17}\mathrm{F}$ single-nucleon pickup reactions were measured at 16.5 MeV/nucleon in inverse kinematics together with elastic and inelastic scattering channels. The full set of measured exclusive differential cross sections was compared with the mirror reaction channels on stable ${}^{18}\mathrm{O}$ after consistent reanalysis using coupled reaction channels calculations. Within this interpretation scheme, most of the spectroscopic factors extracted for the population of unbound states in ${}^{17}\mathrm{F}$ match within uncertainties with their mirror partners in ${}^{17}\mathrm{O}$. However, for the deeply bound neutron removal channel to ${}^{17}\mathrm{Ne}$, a significant symmetry breaking with the mirror proton-removal channel leading to ${}^{17}\mathrm{N}$ is evidenced by an overall single-particle strength reduction.

In this work, under the framework of the vector meson dominance model, the trace anomaly contribution value inside neutrons is extracted for the first time based on vector meson photoproduction data. Furthermore, we systematically compare and analyze the trace anomaly contributions of protons and neutrons. The results show that the trace anomaly contributions of protons and neutrons are close, which indirectly confirms that their internal structures and dynamic properties may have certain similarities. In addition, the main factors affecting the extraction of the trace anomaly contribution of nucleons are discussed in detail. This study not only provides a theoretical basis for us to better understand the source of nucleon mass but also makes a useful exploration and discussion on how to extract the trace anomaly contribution of nucleons more accurately in the future.

Nuclear mass measurements have recently been extended conspicuously to proton-rich region in the upper $fp$ shell. The new data are utilized to study isospin symmetry breaking phenomena using Coulomb displacement energy (CDE) and triplet displacement energy (TDE) as probes. The new mass data, either measured for the first time or with greatly improved accuracy, removed several previously found anomalies in the systematical behavior in the $fp$ shell. Remarkably, more regular odd-even staggering patterns can be established in both CDE and TDE, calling for a uniform explanation in terms of isospin-nonconserving (INC) forces across the $sd$, $f_{7/2}$, and upper $fp$ shells. By extending the large-scale shell-model calculation [Phys. Rev. Lett. 110, 172505 (2013)] to the upper $fp$-shell region, we found that, in order to describe the new data, the same INC force is required as previously used for the $f_{7/2}$ shell. Especially, we propose the $T=1$ TDE for those triplet nuclei, that have $pp$, $nn$, and $pn$ pairs on top of a common even-even $N=Z$ core, to be a good indicator for the isotensor component of isospin violating interactions, which is estimated here to be 150 keV.

In this paper we focus on three mass regions where first-order phase transitions occur, namely, for $N=40$, 60, and 90. We investigate four isotopic chains (Se, Zr, Mo, and Nd) in the framework of microscopic Skyrme-Hartree-Fock$+$Bardeen-Cooper-Schrieffer calculations for 15 different parametrizations. The microscopic calculations show the typical behavior expected for first-order phase transitions. To find the best candidate for the critical point phase transition we propose different microscopic position and occupation indices calculated for positive-parity and negative-parity proton and neutron single-quasiparticle states around the Fermi level. The microscopic calculations are completed by macroscopic calculations within the algebraic collective model (ACM), and compared with the experimental data for ${}^{74}\mathrm{Se}$, ${}^{102}\mathrm{Mo}$, and ${}^{150}\mathrm{Nd}$, considered to be the best candidates for the critical-point nuclei.

Background: In the selenium isotopes various shape phenomena are present, in particular, the emergence of a dominant oblate deformation in the most neutron-deficient isotopes has been observed. The scenario of shape coexisting oblate and prolate bands has been proposed across the isotopic chain, with the crossing point of such bands being located near ${}^{70}\mathrm{Se}$, where no coexistence has yet been identified.

Purpose: To determine the presence or absence of any low-lying $0^{+}$ state in ${}^{70}\mathrm{Se}$, confirm the level structure, and interpret the nuclear deformation with theoretical models.

Methods: A combined internal-conversion-electron and $\gamma$-ray spectroscopy study was undertaken with the SPICE and TIGRESS spectrometers at the TRIUMF-ISAC-II facility. Nuclear models were provided by the generalized triaxial rotor model (GTRM) and the collective generalised Bohr Hamiltonian (GBH).

Results: Despite a comprehensive search, no evidence was found for the existence of a $0^{+}$ state below 2 MeV in ${}^{70}\mathrm{Se}$. Significant discrepancies to the previously established positive-parity-level scheme were found. GBH calculations using UNEDF1 mass parameters were found to reproduce the revised low-lying level structure well.

Conclusion:${}^{70}\mathrm{Se}$ does not have a well-defined axial shape. The $2_2^{+}$ state at 1601 keV resembles a quasi-$\gamma$ excitation rather than a member of a shape coexisting band; the presence of such a band is all but ruled out.

Artificial neural networks (ANNs) can be used to learn complex representations of data, enabling new approaches to modeling and processing in the physical sciences. In this work, ANNs are employed to calculate the $\alpha$-decay half-lives of nuclei. An improvement in the predictive power of the ANN models can be achieved by incorporating the angular momentum transferred by $\alpha$ particle and the quadrupole deformation of parent nuclei. Consequently, the root-mean-square deviation between the ANN-predicted $\alpha$-decay half-lives and the experimental data is reduced from 0.581 to 0.334. Predictions are made for the $\alpha$-decay half-lives of isotopes with $Z=117$, 118, 119, and 120. Based on the characteristics (or systematics) of the $\alpha$-decay half-lives, we propose that $N=184$ is a closed neutron shell beyond $N=126$.

In this work, we first derive the evolution equation for the general energy-momentum moment of $\delta f$, where $\delta f$ is the deviation from the local equilibrium phase-space density. We then introduce a relativistic extension of regularized hydrodynamics developed in the nonrelativistic case by Struchtrup and Torrilhon that judiciously mixes the method of moments and Chapman-Enskog expansion. Hydrodynamic equations up to the third-order in gradients are then systematically derived within the context of a single species system and the relaxation-time approximation. This is followed by a series of linear stability and causality analysis. For the massless particles without any charge conservation, the third-order hydrodynamics is shown to be linearly stable and causal.

The possibility of the existence of octupole deformation in ${}^{151}\mathrm{Pm}$ has caused interest for about thirty years. In this paper, the observed low-lying positive- and negative-parity structures in ${}^{151}\mathrm{Pm}$ are investigated by the reflection-asymmetric triaxial particle rotor model. The experimental energy spectra, energy staggering, and parity splitting parameters are well reproduced by the theoretical calculations. It is found that, although the energy spectra can be reproduced without the octupole degree of freedom, the calculated $B\left(E1\right)$ values depend sensitively on the octupole deformation parameter ${\beta }_{30}$, and the observed enhanced $E1$ transitions can be reproduced with a notable ${\beta }_{30}=0.07$. The detailed analysis of the intrinsic wave functions shows that these nearly degenerate positive- and negative-parity bands are built on two individual proton configurations, i.e., dominated by $\pi g_{7/2}[\mathrm{\Omega }=5/2]$ and $\pi h_{11/2}[\mathrm{\Omega }=5/2]$, respectively, which differs from the parity doublet bands built on a single parity-mixed configuration.

Utilizing the recently formulated relativistic mean field theory in complex momentum representation, we delve into the impurity effects of hyperons in hypernuclei. Our findings reveal that hyperons exert considerable effects on single-neutron levels, particularly in the deeply bound states such as $1s$ and $1p$. In the case of ${}^{60}\mathrm{Ca}+\mathrm{\Lambda }$, ${}^{60}\mathrm{Ca}+{\mathrm{\Sigma }}^0$, ${}^{60}60+{\mathrm{\Xi }}^0$, and ${}^{60}\mathrm{Ca}+{\mathrm{\Sigma }}^{+}$, the neutron levels are noticeably lower compared to the baseline ${}^{60}\mathrm{Ca}$, indicating an increased neutron capacity and a shift in the neutron drip line. Notably, the introduction of ${\mathrm{\Xi }}^0$ and ${\mathrm{\Sigma }}^{+}$, especially ${\mathrm{\Sigma }}^{+}$, hyperons results in a more pronounced reduction in neutron levels, partially attributed to the positive charge of the latter. Conversely, for ${}^{60}\mathrm{Ca}+{\mathrm{\Sigma }}^{-}$ and ${}^{60}\mathrm{Ca}+{\mathrm{\Xi }}^{-}$, the neutron levels are elevated, partly due to Coulomb attraction. The impurity effects of hyperons are further evidenced in their density distributions. Neutral $\mathrm{\Lambda }$ and ${\mathrm{\Sigma }}^0$ hyperons exhibit similar patterns, but Coulomb effects notably alter the density distributions of ${\mathrm{\Sigma }}^{+}$ and ${\mathrm{\Sigma }}^{-}$. While $\mathrm{\Lambda }$ and ${\mathrm{\Xi }}^{-}$ possess comparable central densities, the diffuse distribution of ${\mathrm{\Xi }}^{-}$ hints at the formation of a hyperon halo. This study offers valuable insights into the intricate interactions between hyperons and nucleons within hypernuclei.

Renewed interest in neutron-induced reactions on chlorine isotopes has led to a surge of new measurements. Much of this effort has been spurred to inform on the many modern applications in which chlorine plays an important role, e.g., molten salt reactor design and reaction rate calculations for nuclear astrophysics. In this work, we report new ${}^{35}\mathrm{Cl}(n,p)$ and ${}^{35}\mathrm{Cl}(n,\alpha )$ partial and total cross sections measured at the Los Alamos Neutron Science Center using the LENZ [Low-Energy ($n,Z$)] experimental setup, complementary to those published previously. The data span incident neutron energies from 300 keV to 12 MeV, extending beyond the previous study, and are consistent in magnitude and fluctuation. We also report on an effort at LANL to reanalyze the ${}^{35}\mathrm{Cl}(n,X)$ system in the fast (statistical) energy range under a Hauser-Feshbach formalism, including the latest data. The leading results are an overall reduction in neutron absorption in the fast-energy range compared to base (global) optical model values, due to the low level density of the compound (${}^{36}\mathrm{Cl}$) system, but a net increase in cross section at the higher energies ($>10\mathrm{MeV}$) modeled through an enhanced preequilibrium component, an energy range potentially relevant for fusion applications. The cross-cutting impacts of these results on some of the referenced applications are discussed, including extensions of the analysis to neighboring isotopes. The calculations described here provide a foundation for a future update to the ENDF/B nuclear data library.

The strange dibaryons $p\mathrm{\Omega }$ $\left({}^5\mathrm{S}_2\right)$ and $\mathrm{\Omega }\mathrm{\Omega }$ $\left({}^1\mathrm{S}_0\right)$ are likely bound, existing either in molecular states like the deuteron or as more exotic compact six-quark states. Here, we investigate the production of these two dibaryons in $\mathrm{Pb}+\mathrm{Pb}$ collisions at $\sqrt{s_{NN}}=2.76$ TeV at the CERN Large Hadron Collider within a covariant coalescence model, which employs a blast-wave-like parametrization for the phase-space configurations of constituent particles at freeze-out. For the molecular states, the $p\mathrm{\Omega }$ and $\mathrm{\Omega }\mathrm{\Omega }$ are produced via $p\text{−}\mathrm{\Omega }$ and $\mathrm{\Omega }\text{−}\mathrm{\Omega }$ coalescence, respectively, while for the six-quark states, they are formed through $uudsss$ and $ssssss$ coalescence. We find that the yield ratios $N_{p\mathrm{\Omega }}/N_{\mathrm{\Omega }}$ and $N_{\mathrm{\Omega }\mathrm{\Omega }}/N_{\mathrm{\Omega }}$ have a distinct centrality dependence between the molecular and multiquark states, thus offering a promising way for distinguishing the two states. Our results suggest that the measurements of $p\mathrm{\Omega }$ and $\mathrm{\Omega }\mathrm{\Omega }$ production in relativistic heavy-ion collisions can shed light on their internal structures.

Employing the recently developed EPOS4HQ event generator, we study the production of different heavy-flavor mesons in relativistic heavy-ion collisions at BNL Relativistic Heavy Ion Collider and CERN Large Hadron Collider energies. The transverse momentum spectra, yield ratio, nuclear modification factor, and elliptic flow can be well described in the EPOS4HQ framework. We furthermore analyze the processes which modify these observables as compared to $pp$ collisions and are at the origin of the experimentally determined nuclear modification factor $R_{AA}$.

Repulsive short-range interactions can induce $p$-wave attraction between fermions in dense matter and lead to Cooper pairing at the Fermi surface. We investigate this phenomenon, well known as the Kohn-Luttinger effect in condensed-matter physics, in dense matter with strong short-range repulsive interactions. We find that repulsive interactions required to stabilize massive neutron stars can induce $p$-wave pairing in neutron and quark matter. When massive vector bosons mediate the interaction between fermions, the induced interaction favors Cooper pairing in the ${}^{3}P_2$ channel. For the typical strength of the interaction favored by massive neutron stars, the associated pairing gaps in neutrons can be in the range of 10 keV to 10 MeV. Strong and attractive spin-orbit and tensor forces between neutrons can result in repulsive induced interactions that greatly suppress the ${}^{3}P_2$ pairing gap in neutron matter. In quark matter, the induced interaction is too small to result in pairing gaps of phenomenological relevance.

Excited states in the ${}^{70}\mathrm{Kr}$ and ${}^{70}\mathrm{Br}$ nuclei were populated via the ${}^{40}\mathrm{Ca}({}^{32}\mathrm{S},2n){}^{70}\mathrm{Kr}$ and ${}^{40}\mathrm{Ca}({}^{32}\mathrm{S},pn){}^{70}\mathrm{Br}$ fusion-evaporation reactions at the Accelerator Laboratory of the University of Jyväskylä. The $2^{+}⟶0^{+}$ and $4^{+}⟶2^{+}$ transitions in ${}^{70}\mathrm{Kr}$ have been found to be 881(1) keV and (tentatively) 1037(2) keV, respectively. Several new $\gamma$-ray transitions were also identified in ${}^{70}\mathrm{Br}$, and the $T=1$ band has been tentatively extended up to $J^{\pi }={10}^{+}$. The newly observed transitions in ${}^{70}\mathrm{Kr}$ and ${}^{70}\mathrm{Br}$ resolve discrepancies in the previously reported results for these nuclei. The experimental Coulomb, triplet, and mirror energy differences are compared with the results of two independent shell-model calculations. The comparisons aim to investigate the shape evolution and the role of the isospin breaking interactions in this mass region.

This study explores the transverse momentum ($p_T$) dependencies of symmetric and asymmetric correlations (SC and ASC) with one and two particles of interest in $\mathrm{Au}+\mathrm{Au}$ collisions at 200 GeV. Leveraging a multiphase transport (AMPT) model, the investigation delves into the sensitivity of these correlations to the final state effects, providing valuable insights into their potential for constraining the final state effects' $p_T$ dependencies. The HIJING model is employed as a benchmark for nonflow correlations, shedding light on their impact on interpreting SC and ASC data. Moreover, the study points out that differential SC and ASC with one and two particles of interest (POIs) typically incorporate contributions from event-plane angle fluctuations. Consequently, this work highlights the significance of SC and ASC with one and two POIs as valuable tools for investigating the $p_T$ nature of the final state effects and advocates for comprehensive experimental measurements across various beam energies and system sizes to enhance understanding and provide additional constraints for theoretical models.

We examine the behavior of charged pions in neutron-rich matter using heavy-baryon chiral perturbation theory. This study is motivated by the prospect that pions, or pionlike excitations, may be relevant in neutron-rich matter encountered in core-collapse supernovae and neutron star mergers. We find, as previously expected, that the ${\pi }^{-}$ mass increases with density and precludes $s$-wave condensation at $n_B\lesssim n_{\mathrm{sat}}$, where $n_{\mathrm{sat}}\approx 0.16{\mathrm{fm}}^{-3}$ is the nuclear saturation density, and the mass of the ${\pi }^{+}$ mode decreases with density. The uncertainty in these predictions increases rapidly for $n_B\gtrsim n_{\mathrm{sat}}$ because low-energy constants associated with the two-pion-two-nucleon operators in chiral perturbation theory are poorly constrained. These uncertainties are especially large in symmetric nuclear matter and should be included in the analysis of pion-nucleus interactions at low-energy and pionic atoms. In neutron-rich matter, accounting for the self-energy difference between neutrons and protons related to the nuclear symmetry energy has several effects. It alters the power counting of certain higher-order contributions to the pion self-energy. Previously unimportant but attractive diagrams are enhanced, resulting in a modest reduction of the pion masses. Furthermore, in the long-wavelength limit, a collective mode with the quantum numbers of the ${\pi }^{+}$ appears.