We construct a four-dimensional version of the equation of state (EoS) model neos, neos-4d, as a function of the temperature and chemical potentials of baryon, electric charge, and strangeness for the hot and dense quantum chromodynamics (QCD) matter created in relativistic nuclear collisions. This EoS enables multiple conserved charge current evolution in a relativistic fluid. Input from lattice QCD simulations and a hadron resonance gas model is considered for constructing the equation of state. We investigate its applicability to the relativistic hydrodynamic description of nuclear collisions and present a method for efficient numerical implementation.

Excited states of the molybdenum isotopes ${}_{42}{}^{97,99,101}\mathrm{Mo}$ have been populated in two experiments which used fusion-fission and binary grazing reactions to populate yrast states of the nuclei of interest. In the first experiment, the GASP array of escape-suppressed Ge detectors was used to detect $\gamma$ rays from fusion-fission products initiated by the interaction of a 230-MeV beam of ${}^{36}\mathrm{S}$ ions with a thick target of ${}^{176}\mathrm{Yb}$. In the multinucleon transfer experiment, a 530-MeV beam of ${}^{96}\mathrm{Zr}$ ions was incident on a thin ${}^{124}\mathrm{Sn}$ target; projectile-like ejectiles were detected and identified using the PRISMA magnetic spectrometer and their associated $\gamma$ rays were detected using the CLARA array of escape-suppressed Ge detectors. In ${}^{99}\mathrm{Mo}$, the previously known positive-parity $\nu {\mathrm{d}}_{5/2}$ decay sequence was extended to spin ($25/2^{+}$) while, in ${}^{101}\mathrm{Mo}$, a similar, but hitherto unobserved $\nu {\mathrm{g}}_{7/2}$ positive-parity decay sequence was established to spin ($27/2^{+}$). In ${}^{99}\mathrm{Mo}$ and in ${}^{101}\mathrm{Mo}$, previously observed $\nu h_{11/2}$ negative-parity decay sequences were also observed to spin $27/2^{-}$. Although the observed decay sequences in ${}^{97}\mathrm{Mo}$ have not been extended beyond the results of earlier work, a disagreement in the published level structure of the $h_{11/2}$ band has been resolved. The observed positive-parity decay sequences have been compared with the results of state-of-the-art shell-model calculations; the general features of the energy spectrum of excited states of ${}^{97}\mathrm{Mo}, {}^{99}\mathrm{Mo}$, and ${}^{101}\mathrm{Mo}$ are reproduced, but not in detail. The experimental energies of the negative-parity states of ${}^{99}\mathrm{Mo}$ and ${}^{101}\mathrm{Mo}$ are reasonably well reproduced in particle-rotor (PRM) calculations. For ${}^{97}\mathrm{Mo}$, better agreement with the high-spin states was obtained when the core in the PRM calculations was treated in a variable moment of inertia approach. For the $\nu h_{11/2}$ negative-parity decay sequences of the three isotopes studied here, model-dependent evidence is presented for nuclear shape changes with increasing neutron number.

We study an approach to simulating the stochastic relativistic advection-diffusion equation based on the Metropolis algorithm. We show that the dissipative dynamics of the boosted fluctuating fluid can be simulated by making random transfers of charge between fluid cells, interspersed with ideal hydrodynamic time steps. The random charge transfers are accepted or rejected in a Metropolis step using the entropy as a statistical weight. This procedure reproduces the expected stress of dissipative relativistic hydrodynamics in a specific (and noncovariant) hydrodynamic frame known as the density frame. Numerical results, both with and without noise, are presented and compared to relativistic kinetics and analytical expectations. An all order resummation of the density frame gradient expansion reproduces the covariant dynamics in a specific model. In contrast to all other numerical approaches to relativistic dissipative fluids, the dissipative fluid formalism presented here is strictly first order in gradients and has no nonhydrodynamic modes. The physical naturalness and simplicity of the Metropolis algorithm, together with its convergence properties, make it a promising tool for simulating stochastic relativistic fluids in heavy ion collisions and for critical phenomena in the relativistic domain.

In nuclear and particle physics, reconciling sophisticated simulations with experimental data is vital for understanding complex systems like the quark gluon plasma (QGP) generated in heavy-ion collisions. However, computational demands pose challenges, motivating using Gaussian process emulators for efficient parameter extraction via Bayesian calibration. We conduct a comparative analysis of Gaussian process emulators in heavy-ion physics to identify the most adept emulator for parameter extraction with minimal uncertainty. Our study contributes to advancing computational techniques in heavy-ion physics, enhancing our ability to interpret experimental data and understand QGP properties.

Semi-inclusive deep inelastic scattering off nuclei is a unique process to study the parton propagation mechanism and its modification induced by the presence of the nuclear medium. It allows us to probe the medium properties, particularly the cold nuclear matter transport coefficient, which can be directly linked to the nuclear gluon density. We present here a model for hadron production in deep inelastic lepton-nucleus scattering, which takes into account the hadronic transverse momentum of final state particles via transverse-momentum dependent parton distributions and fragmentation functions. We implement parton energy loss and hadronic absorption with a geometrical model of the nucleus. The model is compared with the nuclear semi-inclusive deep-inelastic scattering multiplicity ratios and transverse-momentum broadening data from the CLAS, HERMES, and EMC collaborations, aiming for a simultaneous description of these data sets. We obtain a good agreement over the various nuclear targets and the wide kinematical range of those experiments. We best describe the data with a transport coefficient $\widehat{q}=0.3\mathrm{GeV}/{\mathrm{fm}}^2$, and we highlight the importance and the role of correlations in extracting this quantity.

The power-moderated mean (PMM) method is a new method approved by the Consultative Committee for Ionizing Radiation for calculating a key comparison reference value and its associated standard uncertainty. The PMM method can exclude extreme data based on statistical criteria, and incorporates aspects of the arithmetic mean, the weighted mean, and the Mandel-Paule mean. For the data sets that are suspected of inconsistency, the PMM method can automatically adjust data uncertainties to achieve consistency, moderate the power of the uncertainties in the weighting factors, and thus allow for the calculation of an efficient and robust mean from any data set. The PMM method is applied for the first time to predict nuclear masses based on the mass predictions from various nuclear models. In the known nuclear region, where the theoretical mass predictions of different nuclear models are consistent within uncertainties, the PMM mass prediction approaches a weighted mean of different theoretical mass predictions. When extrapolating to the unknown region, the model uncertainties are underestimated and hence the theoretical mass predictions are inconsistent, the PMM mass prediction approaches an arithmetic mean of different theoretical mass predictions. Therefore, the PMM method provides a tool for a smooth transition of the mass prediction from the weighted mean to the arithmetic mean. The extrapolation performance of the PMM method is further verified by taking the mass predictions of the finite-range droplet model as the pseudoexperimental data, and it is found that the PMM mass predictions can agree with the pseudoexperimental data within uncertainties even far away from the known region, implying that the PMM method provides reliable uncertainty evaluations.

The subdiffusion phenomena are studied for heavy quarks dynamics in the hot QCD matter. Our approach aims to provide a more realistic description of heavy quark dynamics through detailed theoretical analyses and numerical simulations, utilizing the fractional Langevin equation framework with the Caputo fractional derivative. I present numerical schemes for the fractional Langevin equation for subdiffusion and calculate the time evolution mean squared displacement and mean squared momentum of the heavy quarks. My results indicate that the mean squared displacements of the heavy quarks for the subdiffusion process deviate from a linear relationship with time. Further, I calculate the normalized momentum correlation function, kinetic energy, and momentum spread. Finally, I show the effect of subdiffusion on experimental observables, the nuclear modification factor.

We develop a new method to describe electromagnetic observables of open-shell nuclei with two nucleons outside a closed shell. This approach combines the equation-of-motion coupled-cluster method for such systems and the Lorentz integral transform technique, expanding the applicability of coupled-cluster theory for electromagnetic observables beyond closed-(sub)shell nuclei. To validate this new approach, we compute the non-energy-weighted dipole sum rule and the dipole polarizability of ${}^{16,24}\mathrm{O}$ in both the closed-(sub)shell and the new equation-of-motion coupled-cluster frameworks, finding agreement within error bars. We then analyze the evolution of the dipole polarizability along the oxygen and calcium isotopic chains. Our predictions agree well with available experimental data and other available theoretical calculations for the closed-(sub)shell ${}^{16,22}\mathrm{O}$ and the open-shell ${}^{18}\mathrm{O}$. In the calcium isotopes, we observe that our dipole polarizability predictions for open-shell nuclei are lower than those of closed-(sub)shell nuclei. We expect that our predictions for ${}^{24}\mathrm{O}$ and ${}^{54,56}\mathrm{Ca}$ will motivate future experimental studies at the drip line.

One in about a few ${10}^5$ sub-Coulomb $d\text{−}t$ collisions is accompanied by the emission of a $\gamma$ photon. The $\gamma$ spectrum from these collisions is dominated by a 16.7 MeV peak, corresponding to the population of the $p$-wave $3/2^{-}$ $\alpha \text{−}n$ ground-state resonance in the $E1$ transition from an intermediate $d$-wave $\alpha \text{−}n$ state, corresponding to the ${}^5\mathrm{He}$ excited state around 16.7 MeV. The strength of this spectrum at the large $\gamma$-energy endpoint decreases fast both due to kinematic factors and due to centrifugal repulsion between neutron and $\alpha$ particle at near-zero relative energies. However, no centrifugal repulsion would occur if $s$-wave $\alpha \text{−}n$ states were populated in a magnetic dipole transition. Therefore, one can expect that close to the $\gamma$-spectrum endpoint around 17.5 MeV the $M1$ transition could dominate, leading to additional counts in experimental spectra which could be easily misinterpreted as a background. This work presents calculations of the $M1$ contribution to the $d+t\to \alpha +n+\gamma$ cross section caused both by convection and magnetization currents. While the first contribution was found to be negligible, the one from magnetization depends strongly on the choice of the model for the $d\text{−}t$ channel scattering wave function. Using $d\text{−}t$ interaction models from the literature, represented either by a gaussian of by a square well, resulted in unrealistically strong $M1$ contribution. Withoptical folding potential constructed in the present work, correctly representing the sizes of deuteron and triton, the $M1$ contribution near the endpoint is reduced to about $2\%$ of the 16.7-MeV $E1$ peak. Arguments in favor of more detailed calculations, that could potentially change this number, are put forward.

Within the framework of the dinuclear system model taking into account deformation relaxation, the calculated isotopic distributions in the multinucleon transfer reactions ${}^{136}\mathrm{Xe}+{}^{249}\mathrm{Cf}$ and ${}^{86}\mathrm{Kr}+{}^{248}\mathrm{Cm}$ are in good agreement with the experimental data, especially the cross sections of the neutron-rich isotopes. The time-dependent driving potential decreases with evolution time in the ${}^{136}\mathrm{Xe}+{}^{249}\mathrm{Cf}$ reaction, while the ${}^{154}\mathrm{Sm}+{}^{249}\mathrm{Bk}$ reaction shows an opposite trend, due to the different ground-state deformations of the projectiles. The effect of the time-dependent driving potential on the cross section is investigated. The production cross sections of the final fragments are not sensitive to the incident energy. Finally, the cross sections of unknown isotopes in the reaction ${}^{238}\mathrm{U}+{}^{249}\mathrm{Bk}$ are predicted, in which the high $N/Z$ ratio of ${}^{238}\mathrm{U}$ leads to the production of 49 new neutron-rich isotopes in the range $Z=95–100$ with cross sections larger than 1 pb.

We determine the nuclear suppression factor $S_{\mathrm{Pb}}\left(x\right)$, where $x=M_{J/\psi }^2/W_{\gamma p}^2$ with $M_{J/\psi }$ the $J/\psi$ mass and $W_{\gamma p}$ the photon-nucleon energy, for the cross section of coherent $J/\psi$ photoproduction in heavy-ion ultraperipheral collisions at the Large Hadron Collider and Relativistic Heavy Ion Collider by performing the ${\chi }^2$ fit to all available data on the cross section $d{\sigma }^{AA\to J/\psi AA}/dy$ as a function of the $J/\psi$ rapidity $y$ and the photoproduction cross section ${\sigma }^{\gamma A\to J/\psi A}\left(W_{\gamma p}\right)$ as a function of $W_{\gamma p}$. We find that while the $d{\sigma }^{AA\to J/\psi AA}/dy$ data alone constrain $S_{\mathrm{Pb}}\left(x\right)$ for $x\ge {10}^{-3}$, the combined $d{\sigma }^{AA\to J/\psi AA}/dy$ and ${\sigma }^{\gamma A\to J/\psi A}\left(W_{\gamma p}\right)$ data allow us to determine $S_{\mathrm{Pb}}\left(x\right)$ in the wide interval ${10}^{-5}<x<0.05$. In particular, the data favor $S_{\mathrm{Pb}}\left(x\right)$, which decreases with a decrease of $x$ in the ${10}^{-4}<x<0.01$ interval and can be both decreasing or constant for $x<{10}^{-4}$. Identifying $S_{\mathrm{Pb}}\left(x\right)$ with the ratio of the gluon distributions in Pb and the proton $R_g(x,Q_0^2)=g_A(x,Q_0^2)/\left[A{g}_p(x,Q_0^2)\right]$, we demonstrate that the leading twist approximation for nuclear shadowing provides a good description of all the data on $d{\sigma }^{AA\to J/\psi AA}/dy$ and ${\sigma }^{\gamma A\to J/\psi A}\left(W_{\gamma p}\right)$ as well as on the experimental values for $S_{\mathrm{Pb}}\left(x\right)$ derived from ${\sigma }^{\gamma A\to J/\psi A}\left(W_{\gamma p}\right)$. We also show that modern nuclear parton distributions reasonably reproduce $S_{\mathrm{Pb}}\left(x\right)$ as well.

In heavy-ion phenomenology, the nucleon density distribution in colliding nuclei is commonly described by a two-parameter Woods-Saxon (WS) distribution. However, this approach overlooks the detailed radial structure in the density distribution that arises from the quantal filling patterns of neutrons and protons. These fine structures, as estimated by the Skyrme-Hartree-Fock density functional, cause slight deviations in heavy-ion observables from the WS baseline, which cannot be captured by simply readjusting the WS parameters. These deviations depend on centrality and observable but often exhibit similar shapes for different nuclei. To fully exploit the exceptional sensitivity of isobar collisions to nuclear structure, such fine structures should be considered.

The very neutron-deficient strongly deformed ${}^{117}\mathrm{Cs}$ nucleus has been studied using the ${}^{58}\mathrm{Ni}({}^{64}\mathrm{Zn},1\alpha 1p$) reaction and JUROGAM 3 $\gamma$-ray detector array coupled to the MARA recoil-mass separator. Three previously known and three newly identified rotational bands were observed up to very high spin and excitation energy. All bands are firmly assigned to ${}^{117}\mathrm{Cs}$ based on measured mass spectra and interconnecting transitions. The ground-state spin and parity are suggested based on the systematics of low-lying states in odd-even cesium nuclei. The systematics of bandheads in cesium nuclei reveal maximum collectivity and deformation is reached for neutron numbers 64–66, corresponding to the middle of the $N=50-82$ magic shell. The rotational frequencies of the first and second crossings in the different bands are similar to those observed in the corresponding bands in the neighboring ${}^{119}\mathrm{Cs}$ nucleus, suggesting similar deformations of the two nuclei, but enhanced softness in ${}^{117}\mathrm{Cs}$. Particle number conserving cranked shell model calculations describe the observed band structures well.

The relation between the pion's quark distribution function, $q\left(x\right)$, its light-front wave function, and the elastic charge form factor, $F\left({\mathrm{\Delta }}^2\right)$, is explored. The square of the leading-twist pion wave function at a special probe scale, ${\zeta }_H$, is determined using models and Poincaré covariance from realistic results for $q\left(x\right)$. This wave function is then used to compute form factors with the result that the Drell-Yan-West and quark counting relationships are not satisfied. A new relationship between $q\left(x\right)$ and $F\left({\mathrm{\Delta }}^2\right)$ is proposed.

The new isotope ${}^{227}\mathrm{Pu}$ has been produced in the fusion-evaporation reaction ${}^{192}\mathrm{Os}({}^{40}\mathrm{Ar},5n){}^{227}\mathrm{Pu}$ at the gas-filled recoil separator SHANS, and identified using a well-established implantation-decay correlation technique. From the nine observed decay chains, the $\alpha$-particle energy and half-life of ${}^{227}\mathrm{Pu}$ were measured to be 8191(28) keV and $0.{78}_{-0.19}^{+0.39}$ s, respectively. The $\alpha$ decay, when analyzed using the reduced decay width, was tentatively assigned to be a hindered $\alpha$ transition with angular-momentum change of $\mathrm{\Delta }L=2$.

The tilted-axis cranking model based on covariant density functional theory has been used to study the positive-parity $\mathrm{\Delta }I=2$ sequences in ${}^{138}\mathrm{Nd}$ and ${}^{138}\mathrm{Sm}$ nuclei. The energy spectra, the relation between spin and rotational frequency, the dynamic ${\mathrm{Im}}^{\left(2\right)}$ moment of inertia, and the $B\left(E2\right)$ and ${\mathrm{Im}}^{\left(2\right)}/B\left(E2\right)$ values are calculated and in good agreement with the available experimental data. By the further analysis of orientation of angular momentum, the antimagnetic rotation resulting from the coupling of two $h_{11/2}$ neutron holes to the aligned pairs of $h_{11/2}$ proton particles is clearly illustrated in ${}^{138}\mathrm{Nd}$ and ${}^{138}\mathrm{Sm}$, which is different from the previously discussed antimagnetic rotation with two proton blades. This gives a further hint that the antimagnetic rotation with two neutron blades can be realized in specific bands in nuclei.

We use the large-scale nuclear shell model to calculate the nuclear matrix elements for the neutrino-mediated neutrinoless double-$\beta$ decay within the left-right symmetric model for four nuclei: ${}^{76}\mathrm{Ge}, {}^{82}\mathrm{Se}, {}^{130}\mathrm{Te}$, and ${}^{136}\mathrm{Xe}$. We perform a systematic analysis on the general magnitude of different terms for related mechanisms. For the $\eta$ mechanism, we find that the weak magnetism $R$ term dominates the decay rate while the $p$-wave effect is suppressed. While for the $\lambda$ mechanism, the $\omega$ and the $q$ terms are with equal importance. For the latter $q$ term, important contributions from weak-magnetism part are observed. Finally, we give the constraints on the new physics parameters $m_{\beta \beta }, \lambda$, and $\eta$ from current experiments.

Based on the $Q_{p/\alpha }$ values deduced from the linear extrapolations along isotopic chains and on the universal decay law, the proton- and $\alpha$-decay partial half-lives are calculated for odd-$Z$, even-$N$ neutron-deficient Bi–Pa isotopes. Eight proton-emission states in five new isotopes are suggested, including the $1/2^{+}$ and $9/2^{-}$ states in ${}^{183}\mathrm{Bi}$, the $1/2^{+}$ and $7/2^{-}$ states in ${}^{187,189}\mathrm{At}$, the $1/2^{+}$ state in ${}^{193}\mathrm{Fr}$, and the $9/2^{-}$ state in ${}^{199}\mathrm{Ac}$. The calculated half-lives for the $1/2^{+}$ states in ${}^{183}\mathrm{Bi}$ and ${}^{187}\mathrm{At}$ are around 100 ns, too short to be studied using the recoil separator setups, which strongly encourages the development of new experimental techniques and devices to search for new submicrosecond proton-emitting nuclei.

High-momentum two-particle correlations are a useful tool for studying jet-quenching effects in the quark-gluon plasma. Angular correlations between neutral-pion triggers and charged hadrons with transverse momenta in the range 4–12 $\mathrm{GeV}/c$ and 0.5–7 $\mathrm{GeV}/c$, respectively, have been measured by the PHENIX experiment in 2014 for $\mathrm{Au}+\mathrm{Au}$ collisions at $\sqrt{s_{{}_{NN}}}=200$ GeV. Suppression is observed in the yield of high-momentum jet fragments opposite the trigger particle, which indicates jet suppression stemming from in-medium partonic energy loss, while enhancement is observed for low-momentum particles. The ratio and differences between the yield in $\mathrm{Au}+\mathrm{Au}$ collisions and $p+p$ collisions, $I_{AA}$ and ${\mathrm{\Delta }}_{AA}$, as a function of the trigger-hadron azimuthal separation, $\mathrm{\Delta }\varphi$, are measured for the first time at the BNL Relativistic Heavy Ion Collider. These results better quantify how the yield of low-$p_T$ associated hadrons is enhanced at wide angle, which is crucial for studying energy loss as well as medium-response effects.

The long-standing discrepancy between shell-model and experimental values of the mirror asymmetry in Gamow-Teller transition rates for ${}^{28}\mathrm{Al}\left({\beta }^{-}\right){}^{28m}\mathrm{Si}$ and ${}^{28}\mathrm{P}\left({\beta }^{+}\right){}^{28m}\mathrm{Si}$ is partially resolved by integrating the $p$-orbital contribution into the radial mismatch correction term. This approach offers a potential estimate of the radial mismatch-induced core-orbital contribution based on the French-Macfarlane sum rules, avoiding the need for heavy calculations required by the first-principle shell model. Additionally, the isospin-mixing contribution undergoes considerable improvement through scaling the calculated isospin-mixing correction with the experimental energy separation between the lowest two admixed states, in accordance with results from the two-level model.