We present the measurement of the $p_{\mathrm{T}}$-differential production cross section of $\omega$ mesons in pp and $p$-Pb collisions at $\sqrt{s_{NN}}=5.02$ TeV at midrapidity by ALICE. In addition, the first measurement of the nuclear modification factor $R_{p\mathrm{Pb}}$ for $\omega$ mesons at LHC energies is presented, complementing the existing measurements of lighter neutral mesons such as the ${\pi }^0$ and $\eta$. Within the measured $p_{\mathrm{T}}$ range, the $R_{p\mathrm{Pb}}$ of $\omega$ mesons is compatible with no cold nuclear matter effects within the uncertainties, consistent with previous measurements at lower energies. The $\omega /{\pi }^0$ ratio is presented for both collision systems, showing no collision system dependence within the uncertainties. The comparison to previously published $\omega /{\pi }^0$ ratios at lower and higher collision energies in pp collisions suggests a decreasing trend of the ratio above $p_{\mathrm{T}}$ = 4 GeV/$c$ with increasing collision energy. The data in both collision systems are compared to predictions from PYTHIA 8, EPOS LHC, and DPMJET event generators, revealing significant shortcomings in these models’ ability to describe the production of $\omega$ mesons.

We study numerically the small-$x$ behavior of the nuclear gluon distribution function $G^A(x,Q^2)$ in the next-to-leading order (NLO) approximation of the Gribov-Levin-Ryskin-Mueller-Qiu, Zhu-Ruan-Shen (GLR-MQ-ZRS) nonlinear equation and quantify the impact of gluon recombination in the kinematic range $x\le {10}^{-2}$ and $Q^2\ge 5{\text{GeV}}^2$. The results are comparable to the Rausch-Guzey-Klasen (RGK) [J. Rausch, V. Guzey, and M. Klasen, Phys. Rev. D 107, 054003 (2023)] nuclear gluon distributions and the nCTEQ15 parametrization at the corresponding $Q^2$ values. Using the solutions of $G^A(x,Q^2)$ in the framework of the nonlinear GLR-MQ-ZRS evolution equation, both the linear and nonlinear behaviors of the charm structure functions of nuclei per nucleon, $F_2^{c\overline{c}-A}(x,Q^2)$ and $F_L^{c\overline{c}-A}(x,Q^2)$, are considered. The results reveal that nonlinear corrections play an important role in the charm nuclear reduced cross sections at small $x$ and low $Q^2$ values. The computed results are compared with experimental data from the H1 and ZEUS Collaborations.

This study investigates the effects of strong magnetic fields on antikaon condensation in neutron-star matter using the extended FSUGold model. It is found that the presence of strong magnetic fields alters the threshold density of antikaon condensation significantly, which means the threshold density of antikaon condensation is shifted to higher density compared with the magnetic-field-free case. In the presence of strong magnetic fields, the equation of state (EoS) becomes stiffer than that of the zero-field case. The effects of the $\sigma$-cut scheme on the EoS are also researched when the appearance of antikaon condensation occurred. Through careful choice of the parameter of the $\sigma$-cut scheme, we are able to produce a maximum mass neutron star heavier than $2M_{\mathrm{sun}}$.

We investigate polarization states of the outgoing neutron-proton ($np$) pair in elastic polarized neutron and proton scattering, aiming to find unambiguous evidence for entanglement of their spin states. To obtain complete information about these states, we calculate, using the high-precision nucleon-nucleon potential AV18, the final polarizations of the neutron and proton as well as their spin correlation coefficients, which unequivocally define the corresponding spin density matrix. We compute all terms contributing to polarizations and spin correlations, e.g., not only induced polarizations and correlations resulting from unpolarized $np$ scattering but also contributions from single polarization and correlation transfers from individual polarized incoming nucleons and, for the first time, allotment to both quantities stemming from a doubly spin polarized initial state. We find that for the most part the final spin states are statistical mixture of states. The only pure states occur for highly polarized incoming neutrons and protons with maximal polarizations. By quantifying the degree of entanglement through entanglement power and concurrence, we observed that the entanglement of impure final states increases with energy. Among the pure spin states resulting from incoming states with maximal neutron and proton polarizations, we found, at $E_{\mathrm{lab}}=100$ MeV, cases of strongly entangled Bell-type states with only a small admixture of entanglement-spoiling contributions.

A triaxial relativistic Hartree-Bogoliubov theory in continuum (TRHBc) has been developed to incorporate triaxial deformation, pairing correlations, and continuum effects in a fully microscopic and self-consistent way, aiming for a reliable description of triaxial exotic nuclei with extreme neutron-to-proton ratios. The TRHBc formalism is presented in detail, and its numerical implementation is benchmarked against the results from the axially deformed relativistic Hartree-Bogoliubov theory in continuum and the TRHB theory in harmonic-oscillator expansion. The TRHBc theory is applied to investigate the aluminum isotopes systematically, and the available data are well reproduced for the binding energies, one- and two-neutron separation energies, and charge radii. The nuclei near the one-neutron drip line, ${}^{40}\mathrm{Al}$ and ${}^{42}\mathrm{Al}$, are found to be triaxially deformed with one-neutron separation energies below 1 MeV. Possible neutron halos in the triaxial nuclei ${}^{40}\mathrm{Al}$ and ${}^{42}\mathrm{Al}$ are explored by examining the single-particle levels around the Fermi surface, including their composition and contribution to the total neutron density. The existence of neutron halos in ${}^{40}\mathrm{Al}$ and ${}^{42}\mathrm{Al}$ is also supported by the halo scale, which is comparable to other halo nuclei well-established previously. More importantly, the mechanism for the halo formation in ${}^{40}\mathrm{Al}$ is revealed to be the triaxial deformation, which results in the decoupling of the halo orbitals from those of the core.

The background field formalism based on effective actions is a compelling framework for developing an effective field theory for nuclear density functional theory. Among the challenges in carrying out this development is handling both the particle-hole and pairing channels beyond the mean-field level, which includes how to incorporate collective degrees of freedom. Here we use the exactly solvable one-dimensional Gaudin-Yang model as a theoretical laboratory to explore candidate approaches. We compare variational perturbation theory (VPT) to ordinary many-body perturbation theory and the inversion method, all to second order in their respective expansions, and verify issues with Hubbard-Stratonovich auxiliary fields. VPT outperforms the other approaches at this level over a wide range of densities. The next steps to extend this approach toward nuclei are outlined.

The photon production process $f\to f+\gamma$ in the presence of a time-dependent chiral chemical potential ${\mu }_5$ is studied. The validity of the adiabatic approximation is demonstrated in the ultrarelativistic limit. Analytical expressions for the photon spectrum are derived for two models of the chiral magnetic conductivity $b_0\propto {\mu }_5$: (i) $b_0\left(t\right)=A_1+B_{1}tanh(t/\tau )$ and (ii) $b_0\left(t\right)=A_2(t/\tau )/(1+t^2/{\tau }^2)$. It is known that, for constant $b_0$, photon emission may exhibit a resonance for one-photon polarization depending on the sign of $b_0$. It is shown that, in model (i), up to two resonances may occur, depending on the sign of the asymptotic values $b_0\left(\infty \right)$ and $b_0(-\infty )$. No resonances are observed in model (ii). Numerical calculations are performed using parameters relevant to quark-gluon plasma, and the universality of the results is discussed.

We study magnetic properties of the hadron resonance gas in the presence of a strong ($0\le B\le 0.15{\mathrm{GeV}}^2$) magnetic field, using physical values of the magnetic moments of hadrons, i.e., including their anomalous parts. The values of these moments are taken from experiment, or when unavailable, from theoretical estimates. We evaluate the conserved charge susceptibilities, finding the expected sizable effects of the anomalous magnetic moments, in particular for the octet baryons, such as the proton and neutron, where they are exceptionally large. We also study in detail the large effects of the magnetic moments of the $\mathrm{\Delta }\left(1232\right)$ states, for which various theoretical estimates and experimental values differ significantly. We compare our model results with the lattice quantum chromodynamics data and find reasonable agreement within the model uncertainty.

A regression analysis of a neutron-star radius was performed. The optimal sets of variables that can be used to predict the neutron-star radius were determined by applying various regression model selection criteria. Uncertainty bounds on the neutron-star radius were derived based on the obtained regression functions and uncertainties of the independent variables. For the regression functions selected by the Akaike information criterion, the dependence of the stellar matter pressure evaluated at the saturation density was analyzed as a function of the neutron-star mass and radius.

Dipole bosons are introduced in the interacting boson model (IBM) by means of the self-consistent mean-field method. The constrained mean-field calculations employing a given nuclear energy density functional yield the potential energy surfaces in terms of the axially symmetric quadrupole-octupole, dipole-quadrupole, and dipole-octupole deformations. By mapping these energy surfaces onto the expectation values of the IBM Hamiltonian in the coherent state of the interacting $s$, $p$, $d$, and $f$ bosons, strength parameters of the $spdf$-IBM Hamiltonian are determined. In an illustrative application to octupole-deformed actinides ${}^{218–230}\mathrm{Ra}$ and ${}^{220–232}\mathrm{Th}$, it is shown that effects of including $p$ bosons in the IBM mapping are to lower significantly negative-parity yrast levels, and to improve descriptions of observed energy-level systematic in nearly spherical and transitional nuclei, and of the behaviors of the reduced electric dipole transitions and intrinsic dipole moments with neutron number.

In the past, the mirror asymmetry parameter has been proposed as a probing mechanism for the presence of beyond the standard model second-class currents in nuclear beta decay transitions. However, this was hindered by large uncertainties in the required nuclear structure correction terms. Recently, a new calculation of these corrections attempted to, but could not fully, explain the negative mirror asymmetry between the ${}^{28}\mathrm{Al}\left({\beta }^{-}\right){}^{28m}\mathrm{Si}$ and ${}^{28}\mathrm{P}\left({\beta }^{+}\right){}^{28m}\mathrm{Si}$ decays. To put the mirror asymmetry parameter on a more solid footing, the half-life of ${}^{28}\mathrm{Al}$ was measured for the first time using a radioactive ion beam at the Nuclear Science Laboratory of the University of Notre Dame. The new result, $t_{1/2}=134.432\left(34\right)$ s, is consistent with most of the past data except for one highly discrepant measurement. The new mirror asymmetry parameter of –3.5(10)$\%$ still does not agree with nuclear structure calculations.

We study the nuclear compositions in the central region of a core-collapse supernova, assuming the existence of dineutrons (${}^{2}n$) and tetraneutrons (${}^{4}n$). At 100 ms after core bounce, ${}^{2}n$ and ${}^{4}n$ are more abundant than deuterons within radii of approximately 100  and 50 km, respectively. Compared to the model ignoring the existence of ${}^{2}n$ and ${}^{4}n$, the mass fraction of neutrons up to a radius of 100 km reduces, while the mass fractions of protons, deuterons, and ${}^4\mathrm{He}$ increase. Due to the uncertainties in the properties of ${}^{2}n$ and ${}^{4}n$, we investigate the influence of their binding energies on the nuclear composition. We find the binding energy of ${}^{2}n$ has only a modest effect on the overall composition, except for its own mass fraction, while that of ${}^{4}n$ has a negligible impact.

We present a new method for extracting a mass parameter using time-dependent density functional theory for an arbitrary physical system, provided the adiabatic limit is achievable. This approach works for collective variables also in the presence of a medium, in particular for the nuclei interacting with a neutron background. We apply the method to extract mass parameters of impurities in the neutron-star crust, like their inertial masses and quadrupole mass parameters. The extracted mass parameters at various depths of the inner crust are compared with other methods, including the hydrodynamic approach. The presented method opens avenues for the construction of an effective model of neutron star crust grounded in microscopic calculations.

The $K^{\pi }=0^{+}$ and $K^{\pi }=4^{+}$ bands of ${}^{52}\mathrm{Cr}$, populated through the ${}^{51}\mathrm{V}({}^4\mathrm{He},2np){}^{52}\mathrm{Cr}$ reaction with a 45 MeV ${}^4\mathrm{He}$ beam, have been studied using the Indian National Gamma Array (INGA) facility. The level scheme has been verified utilizing the results of intensity, directional correlation, and linear polarization measurements. Lifetimes of a few excited states in the observed bands have been measured/remeasured using the Doppler shift attenuation method (DSAM). Large basis shell model calculations have been performed within the $fp$ valence space to understand the microscopic origin of these bands. Structural evolution and $K$ mixing throughout the bands in ${}^{52}\mathrm{Cr}$ have been investigated using the calculated quadrupole moments ($Q_s$) and the results obtained from one-nucleon transfer spectroscopic factor calculations.

The $\beta$-delayed spectroscopy of ${}^{80}\mathrm{Ge}$ has been studied using sources of ground and low-lying isomeric states of ${}^{80}\mathrm{Ga}$. A hybrid $\gamma$-ray spectrometer was used, composed of high-purity germanium (HPGe) detectors for low-energy $\gamma$-ray detection, phoswich detectors from the PARIS array for high-energy $\gamma$ rays and a plastic detector for $\beta$ tagging. The new decay level schemes are presented, with 13 and 14 states $\beta$ populated by ${}^{80g}\mathrm{Ga}$ and ${}^{80m}\mathrm{Ga}$, respectively, being reported for the first time. We quantitatively compare summed intensities of first-forbidden and previously reported Gamow-Teller $\beta$ transitions [R. Li et al., Phys. Rev. C 111, 034303 (2025)]. The upper-limit fractions of first-forbidden transitions contributing to the decays of ${}^{80g}\mathrm{Ga}$ and ${}^{80m}\mathrm{Ga}$ are ($48.0\pm 2.7$)$\%$ and ($47.9\pm 3.3$)$\%$ of the observed total $\beta$ transition intensities of ($78.2\pm 2.5$)$\%$ and ($82.2\pm 3.7$)$\%$, respectively. Notably, the half-lives decrease in accordance with the upper limits of ($48.0\pm 6.0$)$\%$ [3.67(20) s $\to 1.91\left(3\right)\mathrm{s}$] and ($47.9\pm 7.2$)$\%$ [3.01(19) s $\to 1.57\left(1\right)\mathrm{s}$] for ${}^{80g}\mathrm{Ga}$ and ${}^{80m}\mathrm{Ga}$, respectively, when including first-forbidden transitions, in contrast to those by Gamow-Teller transitions only.

Experimental studies show unique sensitivities of anisotropic flow to the initial state of heavy-ion collisions. In the framework of a multiphase transport model, we study the effect of the initial fluctuations on heavy flavor flow in $\mathrm{Au}+\mathrm{Au}$ collisions at energies available at the BNL Relativistic Heavy Ion Collider. The modification of elliptic and triangular flow of D mesons, as well as charm quarks, due to event-by-event fluctuations of the collision geometry, is investigated using the two-particle correlation method. The relative flow fluctuations of heavy hadrons are examined as a function of the eccentricity fluctuations and compared with the results of light hadrons. Our study suggests that the initial geometric fluctuation has less influence on $v_2$ of D mesons than on that of light hadrons, while exerting a similar impact on the $v_3$ magnitude for both D mesons and light hadrons. Furthermore, the correlation between flow coefficients and initial eccentricities is explored for D mesons and light hadrons, incorporating the effects of final-state hadronic interactions. Our study offers insights into the differences in flow evolution between light- and heavy-flavor hadrons in high-energy heavy-ion collisions.

We investigate the impact of various hadronization mechanisms on strange particle production in inelastic proton-proton collisions at energies available at the CERN Super Proton Synchrotron (SPS), utilizing four configurations of the pythia8 model. These configurations include the popcorn mode, facilitating complex baryonic interactions via increased string tension; the diquark mode, emphasizing direct baryon-antibaryon pair production; the thermal mode, which integrates fluctuations in internal string tension to model thermally influenced particle distributions; and the junction baryon mode, crucial for accurately simulating complex baryon formation. Our analysis addresses rapidity and transverse momentum ($p_T$) distributions for primary strange ($K_s^0, \mathrm{\Lambda }$), hidden strange ($\varphi$), and multistrange (${\mathrm{\Xi }}^{-}, {\overline{\mathrm{\Xi }}}^{+}, {\mathrm{\Xi }}^0, {\overline{\mathrm{\Xi }}}^0$) particles at 158 $\mathrm{GeV}\text{/}c$, and explores dynamics at lower beam energies (31, 40, and 80 $\mathrm{GeV}\text{/}c$) for primary and hidden strange particle production. Results indicate that the popcorn mode provides good agreement with experimental data for primary and multistrange particles but consistently underestimates $\varphi$ production. The diquark mode tends to overestimate yields for $K_s^0$ and ${\overline{\mathrm{\Xi }}}^{+}$, suggesting excessive energy allocation to strange quark generation. Conversely, the thermal mode exhibits robust performance across a wide range of collision energies, accurately reproducing rapidity and transverse momentum spectra for primary strange particles. Nevertheless, it demonstrates a tendency to overestimate multistrange baryon yields, possibly due to enhanced suppression mechanisms. Among the evaluated models, the thermal mode most effectively describes strange particle production, providing a reliable framework for understanding high-energy hadronic interactions, although further refinements are required to fully capture the intricacies of multistrange particle formation.

In this work, I present new extractions of the proton's $\langle r_{Ep}\rangle$ and neutron's $\langle r_{En}^2\rangle$ conventional charge radii. This analysis is based on two-photon-exchange (TPE) corrected elastic electron-proton cross section ${\sigma }_R$ data from the Mainz experiment, covering the range $0.0155\le Q^2\le 1.0{\mathrm{GeV}}^2$, and updated neutron electric $G_E^n\left(Q^2\right)$ data spanning $0.00973\le Q^2\le 3.410{\mathrm{GeV}}^2$. Both $G_E^{(p,n)}\left(Q^2\right)$ form factors were fit independently using various functional forms and parametrizations that enforce proper low-$Q^2$ constraints. Charge radii were extracted from fits over multiple $Q^2$ intervals, with final values obtained from statistically stable regions. The resulting proton charge radius $\langle r_{Ep}\rangle =0.853\pm 0.{001}_{\text{(stat.)}}\pm 0.{001}_{\text{(sys.)}}\mathrm{fm}$ is consistent with both PRad I and muonic hydrogen results, and falls within the range of values reported in recent reanalyses. The neutron charge radius $\langle r_{En}^2\rangle =-0.106\pm 0.{003}_{\text{(stat.)}}\pm 0.{002}_{\text{(sys.)}} {\mathrm{fm}}^2$ also agrees with modern determinations. Additionally, the charge radii of the baryonic core (three valence quarks) and quark-antiquark meson cloud components of the nucleon are extracted. My results support the $1/2$-fermi size scale of the baryonic core, and $0.617\mathrm{fm}$ of the mesonic cloud of the nucleon, in good agreement with lattice QCD calculations based on dispersion relations and the functional spectral analysis approach. The flavor-separated mean-squared transverse charge distributions of the up- and down-quark $\langle b_{(u,d)}^2\rangle$ radii are also studied, revealing subtle but non-negligible differences in their spatial extent.

The first-forbidden nonunique $\beta$ decay of ${}^{113m}\mathrm{Cd}$ was studied at the Gran Sasso underground laboratory of INFN with the help of a cadmium tungstate crystal scintillator enriched in ${}^{106}\mathrm{Cd}$ and contaminated by ${}^{113m}\mathrm{Cd}$ at level of $\approx$(14–28) Bq. The half-life of ${}^{113m}\mathrm{Cd}$ was determined through $\beta$ spectra analysis under low-background conditions recorded in 2009, 2015, and 2023, yielding $T_{1/2}=13.{61}_{-0.29}^{+0.22}$ yr. The isomeric transition branching ratio and the $\gamma$-ray energy for the ${}^{113m}\mathrm{Cd}$ decay to the ${}^{113}\mathrm{Cd}$ ground state were refined to 0.0790(21)% and 263.36(4) keV through ultralow-background $\gamma$-spectrometry using high-purity germanium (HPGe) detectors. The $\beta$-decay half-life limit for ${}^{113m}\mathrm{Cd}$ to the $1/2^{-}$ 391.699 keV metastable state of ${}^{113}\mathrm{In}$ was set for the first time as $T_{1/2}\ge 8.6\times {10}^6$ yr. The latter process was considered theoretically within the shell-model framework.

The nature of confinement is connected with color charge. Unfortunately, the color charge densities in QCD, the Noether charge densities associated with the global color invariance, are not invariant under local color rotations. This implies that the expectation values of the net color charge in any region of any physical state in QCD—states that satisfy the color Gauss law—are automatically zero for all components of color. In this Letter, it is shown that the expectation value of the square of the net color charge in a region—a measure of the color charge fluctuations—is necessarily nonzero when evaluated in physical states and the result, while depending on the scheme and scale by which the theory is regulated, is gauge invariant. This holds despite the formal lack of gauge invariance of the operator. Moreover, there is a particular combination of the color charge fluctuations for the vacuum and for a system describable by a nontrivial density matrix that is independent that has a well-defined continuum limit.