Recently the PHENIX Collaboration has made available two-particle correlation Fourier coefficients for multiple detector combinations in minimum bias $p+p$ and 0–5% central $p+\mathrm{Au}$, $d+\mathrm{Au}$, and ${}^3\mathrm{He}+\mathrm{Au}$ collisions at $\sqrt{s_{{}_{NN}}}$ = 200 GeV [Phys. Rev. C 105, 024901 (2022)]. Using these coefficients for three sets of two-particle correlations, azimuthal anisotropy coefficients $v_2$ and $v_3$ are extracted for midrapidity charged hadrons as a function of transverse momentum. In this paper, we use the available coefficients to explore various nonflow hypotheses as well as to compare the results with theoretical model calculations. The nonflow methods fail basic closure tests with ampt and pythia/angantyr, particularly when including correlations with particles in the low multiplicity light-projectile going direction. In data, the nonflow adjusted $v_2$ results are modestly lower in $p+\mathrm{Au}$ and the adjusted $v_3$ results are more significantly higher in $p+\mathrm{Au}$ and $d+\mathrm{Au}$. However, the resulting higher values for the ratio $v_3/v_2$ in $p+\mathrm{Au}$ at RHIC compared to $p+\mathrm{Pb}$ at the LHC is additional evidence for a significant overcorrection. Incorporating these additional checks, the conclusion that these flow coefficients are dominated by initial geometry coupled with final-state interactions (e.g., hydrodynamic expansion of quark-gluon plasma) remains true, and explanations based solely on initial-state glasma are ruled out. The detailed balance between intrinsic and fluctuation-driven geometry and the exact role of weakly versus strongly coupled prehydrodynamic evolution remains an open question for triangular flow, requiring further theoretical and experimental investigation.

We derive the general analytical expressions for the statistical uncertainties of cumulants up to fourth order including an efficiency correction. The analytical expressions have been tested with a toy Monte Carlo model analysis. An application to the study of particle multiplicity fluctuations in heavy-ion collisions is investigated. In this derivation, a mathematical proof is given that the validity of an averaged efficiency correction and the fluctuations induced by the nonuniformity of efficiency can be eliminated. The estimation of statistical uncertainties using the analytical formulas is found to be significantly faster than the commonly used bootstrap method. The simplicity and efficiency of using the analytical formulas may be useful for massive data analysis in many fields.

A detailed reanalysis of the single gluon emission rate at next-to-leading twist is carried out. As was the case in prior efforts, the problem is cast in the framework of deep-inelastic scattering (DIS) of an electron off a large nucleus. The quark produced in the interaction propagates through the remaining nucleus and engenders scattering and gluon radiation, which is calculated in the limit of one rescattering. This medium induced single gluon emission rate forms the basis of several energy loss calculations in both DIS and heavy-ion collisions. Unlike prior efforts, a complete transverse momentum gradient expansion of the hadronic tensor, including $N_c$ suppressed terms, phase terms, and finite gluon momentum fraction terms, ignored previously, is carried out. These terms turn out to be surprisingly large. In contrast to prior efforts, the full next-to-leading twist gluon emission kernel is found to be positive definite and slowly increasing with the exchanged transverse momentum. Phenomenological consequences of these new contributions are discussed.

Flux-integrated semiexclusive differential and integral cross sections for quasielastic neutrino charged-current scattering on argon are analyzed. The cross sections are calculated using the relativistic distorted-wave impulse approximation and compare with recent MicroBooNE data. I found that the measured cross sections can be described well within the experimental uncertainties with value of the nucleon axial mass $1<M_A<1.2\mathrm{GeV}$. The contribution of the exclusive channel $({\mathbf{\nu }}_{\mathbf{\mu }},\mathbf{\mu }p)$ to the flux-integrated inclusive cross sections is about 50%.

Study of the role of electron screening in $\alpha$ decay is advanced, aimed at experimental testing in storage rings. To this end, systematic calculation of the effect in heavy ions of the nuclei within the Ra to Po domain of $\alpha$ emitters is conducted using the adiabatic approach. The effect obtained is to slow the decay down by an amount within a percent value. It is of the opposite sign compared to predictions by the conventional frozen shell model. The reason for the divergence is pointed out. Testing this difference experimentally in storage ring facilities is discussed.

The shape of a nucleus is one of the fundamental nuclear properties. We perform a systematic investigation of bubble nuclei that also exhibit shape coexistence in Hf, W, Os, Pt, and Hg even-even isotopes using the deformed relativistic Hartree-Bogoliubov theory in continuum. For a systematic study, we first consider nuclear bubble structures and shape coexistence separately. We confirm that deformations and pairing correlations hinder bubble structures by comparing our results with those from relativistic continuum Hartree-Bogoliubov theory that assumes spherical symmetry in nuclei. We then predict candidate isotopes with both bubble structure and shape coexistence. We observe that the depletion fraction factor that characterizes bubble structure is mostly smaller in oblate deformation than in prolate, while some isotopes such as ${}^{206}\mathrm{Os}$ have bubble structures both in oblate and prolate deformations. We compare the proton single-particle energy levels for the candidates of shape coexistence both with only prolate bubble structure and with prolate and oblate bubble structures.

We calculate the Coulomb sum rule of inclusive $(e,e^{\prime })$ reactions from ${}^{12}\mathrm{C}, {}^{40}\mathrm{Ca}, {}^{56}\mathrm{Fe}$, and ${}^{208}\mathrm{Pb}$ in the quasielastic region using various relativistic single-particle models, which include the relativistic Hartree, the nonlinear sigma, the quark-meson-coupling, and the chiral quark-meson-coupling models. We investigate the cross sections calculated in these nuclear models by comparing them with Bates, Saclay, and SLAC data for three-momentum transfer $q$ ranging from 300 to 500 $\mathrm{MeV}/c$. We find that the extracted longitudinal structure functions are not so sensitive to the nuclear model but the transverse structure functions strongly depend on the model. We report that, for three-momentum transfer $q>400 \mathrm{MeV}/c$, the values of the Coulomb sum rule from various nuclear models except the Hartree model are greater than 1.

We establish the updated version of dynamical core-corona initialization framework (DCCI2) as a unified description from small to large colliding systems and from low- to high-transverse-momentum ($p_T$) regions. Using DCCI2, we investigate effects of interplay between locally equilibrated and nonequilibrated systems, in other words, core and corona components in high-energy nuclear collisions. Given experimental multiplicity distributions and yield ratios of $\mathrm{\Omega }$ baryons to charged pions as inputs, we extract the fraction of core and corona components in $p+p$ collisions at $\sqrt{s}=7\mathrm{TeV}$ and $\mathrm{Pb}+\mathrm{Pb}$ collisions at $\sqrt{s_{NN}}=2.76\mathrm{TeV}$. We find core contribution overtakes corona contribution as increasing multiplicity above ${\langle d{N}_{\mathrm{ch}}/d\eta \rangle }_{\left|\eta \right|<0.5}\approx 18$ regardless of the collision system or energy. We also see that the core contribution exceeds the corona contribution only in 0.0–0.95% multiplicity class in $p+p$ collisions. Notably, there is a small enhancement of corona contribution with $\approx 20\%$ below $p_T\approx 1$ GeV even in minimum bias $\mathrm{Pb}+\mathrm{Pb}$ collisions. We find that the corona contribution at low $p_T$ gives $\approx 15-30\%$ correction on $v_2\left\{2\right\}$ at $N_{\mathrm{ch}}\lesssim 370$. This raises a problem in conventional hydrodynamic analyses in which low-$p_T$ soft hadrons originate solely from core components. We finally scrutinize the roles of string fragmentation and the longitudinal expansion in the transverse energy per unit rapidity, which is crucial in initial conditions for hydrodynamics from event generators based on string models.

The Boltzmann equation is the traditional framework in which one extends the time-dependent mean field classical description of a many-body system to include the effect of particle-particle collisions in an approximate manner. A semiclassical extension of this approach to quantum many-body systems was suggested by Uehling and Uhlenbeck in 1933 for both Fermi and Bose statistics, and many further developments of this approach are known as the Boltzmann-Uehling-Uhlenbeck (BUU) equations. Here I introduce a pure quantum version of the BUU type of equations, which is mathematically equivalent to a generalized time-dependent density functional theory extended to superfluid systems. As expected, during nonequilibrium processes the quantum Boltzmann one-body entropy increases during evolution.

Nuclear matrix element (NME) for neutrinoless $\beta \beta$ decay (DBD) is required for studying neutrino physics beyond the standard model by using DBD. Experimental information on nuclear excitation and decay associated with DBD is crucial for theoretical calculations of the DBD-NME. The spin-dipole (SD) NME for DBD via the intermediate SD state is one of the major components of the DBD-NME. The experimental SD giant-resonance energy and the SD strength in the intermediate nucleus are shown for the first time to be closely related to the DBD-NME and are used for studying the spin-isospin correlation and the quenching of the axial-vector coupling, which are involved in the NME. So they are used to help the theoretical model calculation of the DBD-NME. Impact of the SD giant resonance and the SD strength on the DBD study is discussed.

The spectroscopy of ${}^{62}\mathrm{Cu}$ is studied via the ${}^{54}\mathrm{Cr}({}^{12}\mathrm{C},1p3n){}^{62}\mathrm{Cu}$ fusion-evaporation reaction. On the basis of the $\gamma \text{−}\gamma$ coincidence analysis, angular distributions from oriented states, and linear polarization measurement, three positive-parity and three negative-parity level sequences in ${}^{62}\mathrm{Cu}$ are observed, including two new $\gamma$-ray transitions and one new level. The collective structures are discussed in terms of the tilted axis cranking covariant density functional theory. Although not firmly confirmed in experiment, the properties of a magnetic rotational structure with the $\pi {\left(f_{7/2}\right)}^{-1}{\left(p_{3/2}{f}_{5/2}\right)}^2\otimes \nu {\left(g_{9/2}\right)}^1{\left(p_{3/2}{f}_{5/2}\right)}^4$ configuration have been discussed. Its angular momentum generation is probably due to the shears mechanism.

Cross section data for evaporation residues (ERs) produced in the ${}^{16}\mathrm{O}+{}^{208}\mathrm{Pb}$ and ${}^{48}\mathrm{Ca}+{}^{176}\mathrm{Yb}$ heavy-ion fusion-evaporation reactions leading to the same ${}^{224}\mathrm{Th}^{*}$ compound nucleus (CN) were obtained at energies around the fusion reaction barriers with the recoil separator vassilissa. These data for ERs formed in the most probable evaporation channels in both reactions agree with those obtained earlier. ER and fission cross sections for ${}^{16}\mathrm{O}+{}^{208}\mathrm{Pb}$ are well reproduced with model calculations using adjustment of respective model parameters. The mutual comparison of the ER cross sections for the very asymmetric (${}^{16}\mathrm{O}+{}^{208}\mathrm{Pb}$) and more symmetric (${}^{48}\mathrm{Ca}+{}^{176}\mathrm{Yb}$) projectile-target combinations allowed us to obtain the fusion probability value (CN formation probability) imposed by the quasifission effect inherent in the ${}^{48}\mathrm{Ca}+{}^{176}\mathrm{Yb}$ reaction.

We analyze the ${}^{16}\mathrm{C}+p$ and ${}^{16}\mathrm{C}+d$ reactions within the four- and five-body continuum discretized coupled channel method. The ${}^{16}\mathrm{C}$ nucleus is described by a ${}^{14}\mathrm{C}+n+n$ configuration in hyperspherical coordinates. This description reproduces fairly well several ${}^{16}\mathrm{C}$ low-lying states. First we analyze the $2^{+}\to 0^{+}E2$ transition amplitude, which confirms that an effective charge must be introduced to reproduce the experimental value. Then, proton and deuteron elastic and inelastic scattering are investigated by including ${}^{16}\mathrm{C}$ pseudostates, which simulate the ${}^{14}\mathrm{C}+n+n$ continuum. In ${}^{16}\mathrm{C}+d$, the deuteron breakup is taken into account with $p+n$ two-body pseudostates. A fair agreement with experiment is obtained without any fitting parameter. Breakup effects are in general small, but improve the agreement with experiment.

The azimuthal correlations between local flow planes at different (pseudo)rapidities ($\eta$) may reveal important details of the initial nuclear matter density distributions in heavy-ion collisions. Extensive experimental measurements of a factorization ratio ($r_2$) and its derivative ($F_2$) have shown evidence of the longitudinal flow-plane decorrelation. However, nonflow effects also affect this observable and prevent a quantitative understanding of the phenomenon. In this paper, to distinguish decorrelation and nonflow effects, we propose a new cumulant observable, $T_2$, which largely suppresses nonflow. The technique sensitivity to different initial-state scenarios and nonflow effects are tested with a simple Monte Carlo model, and in the end, the method is applied to events simulated by a multiphase transport model (AMPT) for $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrt{s_{NN}}=200$ GeV. We also emphasize that a distinct decorrelation signal requires not only the right sign of an observable but also its proper dependence on the $\eta$ window of the reference flow plane to be consistent with the pertinent decorrelation picture.

Current experiments at the Relativistic Heavy Ion Collider (RHIC) are probing finite baryon densities where the shear viscosity to enthalpy ratio $\eta T/w$ of the quark gluon plasma remains unknown. We use the hadron resonance gas (HRG) model with the most up-to-date hadron list to calculate $\eta T/w$ at low temperatures and at finite baryon densities ${\rho }_B$. We then match $\eta T/w$ to a quantum-chromodynamics-based shear viscosity calculation within the deconfined phase to create a table across $\{T,{\mu }_B\}$ for different crossover and critical point scenarios at a specified location. We find that these new $\eta T/w(T,{\mu }_B)$ values would require initial conditions at significantly larger ${\rho }_B$, compared to ideal hydrodynamic trajectories, to reach the same freeze-out point.

In relativistic heavy-ion collisions, the event-by-event mean transverse momentum fluctuations are sensitive to overlap area and energy density fluctuations in the initial state. We present a framework to calculate $p_{\mathrm{T}}$ fluctuations up to fourth order using standard and subevent methods, which is validated using the HIJING model. We observe a power-law dependence for cumulants of all orders as a function of charged particle multiplicity $N_{\mathrm{ch}}$, consistent with a simple independent source picture. The fluctuation in $pp$ collisions is observed to be larger than for $p+\mathrm{Pb}$, Pb $+$ Pb, and Xe $+$ Xe collisions at the same $N_{\mathrm{ch}}$ due to bias in the number of contributing sources. The short-range correlations are greatly suppressed in the subevent method in comparison to calculations based on the standard method. This paper provides a baseline for transverse momentum fluctuations without the presence of final-state effects.

In this paper, we have provided an improved ansatz for the dependence of the valence quarks distribution functions on the momentum transfer (generalized parton distribution) via calculating the up- and down-valence quark distribution functions for $Q^2=0.5–35\mathrm{Ge}{\mathrm{V}}^2$ using the nucleon structure functions and probing their changes due to momentum transfer changes at the Bjorken $x$-range $x\to 1$ so that this model describes the valence quark distribution function changes due to changes in momentum transfer for $x\to 1$, then by using the presented ansatz, we obtained the Dirac and Pauli form factors of the proton and neutron. Finally, we have compared the calculated form factors in this paper with the results of the other models and experimental data.

Background: The anomalous ${}^{22}\mathrm{Ne}$ abundance measured in certain presolar graphite grains is thought to arise from the decay of ${}^{22}\mathrm{Na}$ that was synthesized at high temperatures in core-collapse supernovas. To better interpret this abundance anomaly, the primary destruction mechanism of ${}^{22}\mathrm{Na}$, the ${}^{22}\mathrm{Na}(p,\gamma ){}^{23}\mathrm{Mg}$ reaction, must be better understood.

Purpose: Determine proton branching ratios of several ${}^{23}\mathrm{Mg}$ excited states that play a role in the high-temperature ${}^{22}\mathrm{Na}(p,\gamma ){}^{23}\mathrm{Mg}$ reaction rate.

Methods: Particle decays of ${}^{23}\mathrm{Mg}$ excited states populated with the previously reported ${}^{24}\mathrm{Mg}(p,d){}^{23}\mathrm{Mg}$ transfer reaction measurement [Kwag et al., Eur. Phys. J. A 56, 108 (2020)] were analyzed to extract proton branching ratios. The reaction was studied using a 31-MeV proton beam from the Holifield Radioactive Ion Beam Facility of Oak Ridge National Laboratory and ${}^{24}\mathrm{Mg}$ solid targets.

Results: Proton branching ratios of several ${}^{23}\mathrm{Mg}$ excited states in the energy range $E_x=8.044\text{−}9.642$ MeV were experimentally determined for the first time for the $p0$ and $p{1}^{\prime }$ ($p1+p2+p3$) decay channels.

Conclusions: These new branching ratios for ${}^{23}\mathrm{Mg}$ levels can provide an experimental foundation for an improved high-temperature rate of the ${}^{22}\mathrm{Na}(p,\gamma ){}^{23}\mathrm{Mg}$ reaction needed to understand production of anomalously high ${}^{22}\mathrm{Ne}$ abundance in core-collapse supernovas.