Nuclear Theory·nucl-th

Tuesday·August 19, 2025

19 papers—11 primary·8 cross-listed

01
About possibility to observe spin dichroism effect (the effect of tensor polarization acquiring) for the effect of tensor polarization acquiring by a nonpolarized deuteron beam passing through the nonpolarized internal target of Nuclotron
S.V. Anischenko · V.G. Baryshevsky · A.A. Gurinovich · V.P. Ladygin
Deuteron passage through a nonpolarized target is accompanied by birefringence effect which reveals as diverse phenomena, namely: rotation of spin and tensor polarization about the momentum direction, spin oscillations, vector polarization conversion to tensor that and vice versa, spin dichroism. Possibility to study deuteron spin dichroism effect i.e. the effect of tensor polarization acquiring by a nonpolarized deuteron beam moving in NuclotronM and passing through its internal target is discussed.
nucl-thhep-phnucl-ex1 citation
02
HFBTHO-AD: Differentiation of a nuclear energy density functional code
Laurent Hascoët · Matt Menickelly · Sri Hari Krishna Narayanan · Jared O'Neal · Nicolas Schunck · Stefan M. Wild
The HFBTHO code implements a nuclear energy density functional solver to model the structure of atomic nuclei. HFBTHO has previously been used to calibrate energy functionals and perform sensitivity analysis by using derivative-free methods. To enable derivative-based optimization and uncertainty quantification approaches, we must compute the derivatives of HFBTHO outputs with respect to the parameters of the energy functional, which are a subset of all input parameters of the code. We use the algorithmic/automatic differentiation (AD) tool Tapenade to differentiate HFBTHO. We compare the derivatives obtained using AD against finite-difference approximation and examine the performance of the derivative computation.
nucl-thComput.Phys.Commun.(2026)·0 citations
03
Cluster-breaking and reconfiguration effects in $_{Λ}^{12} B$ hypernucleus
Jiaqi Tian🇨🇳 · Mengjiao Lyu🇨🇳 · Akinobu Dote🇯🇵 · Zheng Cheng🇨🇳 · Takayuki Myo🇯🇵 · Masahiro Isaka🇯🇵 · Hisashi Horiuchi🇯🇵 · Hiroki Takemoto🇯🇵 · Hiroshi Toki🇯🇵 · Niu Wan🇨🇳 · Qing Zhao🇨🇳
We investigate the cluster-breaking effect and spatial distribution of negative-parity states in the $_{Λ}^{12} B$ hypernucleus using the Hyper-Brink model with cluster-breaking(CB-Hyper-Brink) optimized via Control Neural Network (Ctrl.NN). The results demonstrate that the inclusion of cluster-breaking is essential for accurately reproducing the observed low-lying energy levels and for making reliable predictions of the Hoyle-analog state 1-4 in $_{Λ}^{12} B$ . Cluster-breaking manifests as strong spin-orbit correlations and the dissolution of ideal cluster configurations, as revealed by the analysis of one-body spin-orbit operator expectation values and the spatial overlap with projected cluster bases. The interplay between short-range repulsion and intermediate-range attraction in the Lambda N interaction induces the cluster reconfiguration effect, which is characterized by the coexistence of Lambda-alpha and Lambda-triton correlations; this reconfiguration effect leads to a modest stabilization and shrinkage of cluster structures. The variation in electric quadrupole transition strengths, B(E2), between the ground and Hoyle-analog states serves as a sensitive probe for the degree of cluster-breaking, providing direct evidence for its physical relevance. These findings highlight the crucial role of cluster-breaking in characterizing the hypernuclear structure and offer a comprehensive framework for understanding the interplay between clustering and shell-model dynamics in hypernuclei.
nucl-thPRC(2026)·0 citations
04
From Hyperons to Hypernuclei: A New Route to Unravel Proton Spin Polarization
Dai-Neng Liu · Yun-Peng Zheng · Wen-Hao Zhou · Jin-Hui Chen · Che Ming Ko · Yu-Gang Ma · Kai-Jia Sun · Song Zhang
Ultra-relativistic nuclear collisions create the quark-gluon plasma (QGP) known as the hottest, least viscous, and most vortical fluid ever produced in terrestrial laboratories. Its vortical structure has been uncovered through the spin polarization of Lambda ( $Λ$ ) hyperons, attributed to the spin-orbit coupling that transfers the system's orbital angular momentum to the quark spin, which is then inherited by hadrons via quark recombination or coalescence. However, $Λ$ polarization reflects primarily the strange-quark component, leaving the spin dynamics of the up and down quarks largely unexplored. Although the proton is an ideal probe, its stability makes direct measurements experimentally challenging. Here, we propose to unravel proton spin polarization via hypertriton ( $_{Λ}^{3} H$ ) measurements, exploiting the fact that spin information is preserved when polarized nucleons and $Λ$ coalesce to form hypertriton. We show that, over a broad range of collision energies, the polarizations of proton, $Λ$ , and hypertriton are related by a simple linear scaling law. Since both $Λ$ and hypertriton polarizations can be measured via their self-analyzing weak decays, this linear relation provides a practical experimental avenue for accessing spin polarizations of protons and neutrons-the dominant baryonic degrees of freedom in nuclear collisions.
nucl-thhep-ph8 citations
05
Candidates for three-quasiparticle $K$ -isomers in even-odd Fm-Cn nuclei
P. Jachimowicz · M. Kowal · J. Skalski
Following our study of possible $K$ -isomers in odd-even Md-Rg nuclei, here we continue with searching for three-quasiparticle 1 $ν$ 2 $π$ and 3 $ν$ isomer candidates in even-odd Fm - Cn nuclei. We use the same approach to calculate energies of different nuclear configurations using a microscopic-macroscopic model with the Woods-Saxon potential. We used two versions of pairing: quasi-particle BCS method and particle number projection formalism. The optimal deformations for both ground states and high- $K$ configurations are determined through a four-dimensional energy minimization process. We point out the most promising candidates for high- $K$ isomers and compare them, where possible, with existing experimental data.
nucl-thPRC(2025)·0 citations
06
Probing $N N Ω_{ccc}$ three-body systems with the modern QCD $N Ω_{ccc}$ interaction
Faisal Etminan🇮🇷 · Lucas Happ
Newly, first-principles lattice QCD results at the physical pion mass, $m_{π} ⋍ 137.1$ MeV, have been reported by the HAL QCD Collaboration for the S-wave interaction between the nucleon ( $N$ ) and the triply charmed Omega baryon ( $Ω_{ccc}$ ). The $N Ω_{ccc}$ potentials in the spin-1 $(^{3} S_{1})$ and spin-2 $(^{5} S_{2})$ channels were derived and found to be attractive, though no two-body bound state was supported in these channels. The present work investigates the $N N Ω_{ccc}$ three-body system using the Malfliet-Tjon $N N$ potential. Analyses of spin-1, spin-averaged, and spin-2 $N Ω_{ccc}$ channels (at Euclidean times 16, 17, 18) reveal a three-body bound state only for the d- $Ω_{ccc}$ configuration with spin $(0) 1/ 2^{+}$ and $t / a = 16$ . Its binding energy ( $B_{3} = - 2.255$ MeV) lies slightly below the deuteron's ( $B_{d} = - 2.23$ MeV). Other parameter sets do not yield a bound state, and complex scaling analysis indicates these configurations correspond to virtual states rather than resonances. The Coulomb potential's role was also examined to differentiate charged states.
nucl-thhep-lat1 citation
07
Magnetic dipole moments adjacent to doubly-magic nuclei in self-consistent mean-field theory with realistic spin-isospin and tensor forces
H. Nakada · H. Iwata
Magnetic dipole ( $M 1$ ) moments in nuclei neighboring the doubly-magic core are investigated by the self-consistent mean-field (SCMF) approaches that allow for the breaking of the time-reversal symmetry. By the SCMF calculations with the M3Y-P6 interaction, which keeps realistic spin-isospin and tensor channels, the $M 1$ moments are well reproduced, particularly those in the nuclei adjacent to $j j$ -closed magicity. The results are in better agreement with the data than those with the Gogny-D1S interaction, slightly better than those of UNEDF1 supplemented by a spin-isospin channel adjusted to the $M 1$ moments themselves, and comparable to the shell-model results with the chiral effective-field-theory ( $χ$ EFT) interaction. Analyses via quadrupole moments, occupation numbers and the lowest-order perturbation theory elucidate the cooperative effects of quadrupole deformation and spin correlation on the displacement from the Schmidt values, which has been known in terms of the quenching of the spin matrix elements. It is shown that a significant portion of the spin correlation is carried by the spin-isospin and tensor channels in the effective interaction. However, while agreement is remarkable at $^{131}$ Sn $^{m}$ , $^{133}$ Sn and $^{209}$ Pb, discrepancies remain at the $Z = odd$ nuclei $^{133}$ Sb, $^{207}$ Ti and $^{209}$ Bi, as in the $χ$ EFT-based shell-model results.
nucl-thPRC(2026)·3 citations
08
Influence of Cluster Configurations and Nucleon--Nucleon Scattering Cross-Section on Stopping Power in Heavy-Ion Collisions
S. Y. Yao🇨🇳 · X. G. Deng🇨🇳 · Y. G. Ma🇨🇳
We investigate the impacts of nuclear $α$ -clustering structures and nucleon--nucleon cross-section on nuclear stopping power for $^{16} O$ + $^{40} Ca$ collisions below 300 MeV/nucleon using an extended quantum molecular dynamics (EQMD) model. Our results show that the specific $α$ -clustering configurations of $^{16} O$ --including chain, square, kite, and tetrahedron--have a significant effect on collision dynamics. Among them, the tightly bound tetrahedral structure exhibits the highest stopping power. Moreover, the repulsive Coulomb interaction is found to reduce the stopping power of protons in the Fermi-energy domain. At higher energies, the decreasing trend is influenced by both the nucleon--nucleon cross-section and the mean field.
nucl-thnucl-exPRC(2025)·2 citations
09
Nonlocality parameters of microscopic optical potentials from Skyrme-based nuclear structure models at low energies
Do Quang Tam · N. Hoang Tung · N. Hoang Phuc · T. V. Nhan Hao
We investigate the non-locality parameters $β$ in nucleon-nucleus interactions for $^{16} O$ , $^{40} Ca$ , $^{48} Ca$ , and $^{208} Pb$ using a microscopic optical potential (MOP) derived from nuclear structure models based on Skyrme self-consistent mean-field calculations at low incident energies. No ad hoc adjusted parameters were employed in the present calculations. The analysis reveals that the non-locality parameter exhibits a clear dependence on the radial position within the nucleus, the incident nucleon energy, and the choice of target nucleus. At incident energies below $30$ MeV, the $β$ lies between $0.8$ fm and $1.2$ fm for all considered targets. For the light nucleus $^{16} O$ , the non-locality parameter in the interior is smaller than that on the surface, whereas for medium and heavy nuclei $(^{40} Ca$ , $^{48} Ca$ , and $^{208} Pb$ ), the values are comparable in both regions.
nucl-th0 citations
10
Reaction processes of muon-catalyzed fusion in the muonic molecule $dd μ$ studied with the tractable $T$ -matrix model
Qian Wu · Zhu-Fang Cui · Masayasu Kamimura
Muon-catalyzed fusion has recently regained significant attention due to experimental and theoretical developments being performed. The present authors [Phys. Rev. C {\bf 109} 054625 (2024)] proposed the tractable $T$ -matrix model based on the Lippmann-Schwinger equation to approximate the elaborate two- and three-body coupled-channel (CC) calculations [Kamimura, Kino, and Yamashita, Phys. Rev. C {\bf 107}, 034607 (2023)] for the nuclear reaction processes in the muonic molecule $d t μ$ , $(d t μ)_{J = 0} \to^{4} He + n + μ + 17.6 MeV$ . % or $(^{4} He μ)_{n l} + n + 17.6 MeV$ . The $T$ -matrix model well reproduced almost all of the results generated by the CC work. In the present paper, we apply this model to the nuclear reaction processes in the $dd μ$ molecule, $(dd μ)_{J = 1} \to^{3} He + n + μ + 3.27$ MeV or $t + p + μ + 4.03$ MeV, in which the fusion takes place via the $p$ -wave $d$ - $d$ relative motion. Recently, significantly different $p$ -wave astrophysical $S (E)$ factors of the reaction $d + d \to^{3} He + n$ or $t + p$ at $E ≃ 1$ keV to 1 MeV have been reported experimentally and theoretically by five groups. Employing many sets of nuclear interactions that can reproduce those five cases of $p$ -wave $S (E)$ factors, we calculate the fusion rate of the $(dd μ)_{J = 1}$ molecule using three kinds of methods where results are consistent with each other. We also derive the $^{3} He$ - $μ$ sticking probability and the absolute values of the energy and momentum spectra of the emitted muon. The violation of charge symmetry in the $p$ -wave $d$ - $d$ reaction and the $dd μ$ fusion reaction is discussed. Information on the emitted 2.45-MeV neutrons and \mbox{1 keV-dominant} muons should be useful for the application of $dd μ$ fusion.
nucl-thnucl-exphysics.atom-phPRC(2026)·4 citations
11
Radial oscillations of neutron stars within density-dependent relativistic-mean field model
Xuesong Geng🇨🇳 · Kaixuan Huang🇨🇳 · Hong Shen🇨🇳 · Lei Li🇨🇳 · Jinniu Hu🇨🇳
The radial oscillations of neutron stars are studied using equations of state derived from density-dependent relativistic mean-field (DDRMF) models, which effectively describe the ground-state properties of finite nuclei. A novel numerical approach, the finite volume method (FVM), is employed to solve the eigenvalue problem associated with oscillation frequencies. Compared to conventional methods such as the finite difference method and shooting method, the FVM avoids the numerical instability encountered at high frequencies with an equation of state that includes a discontinuous adiabatic index and offers greater computational efficiency. The oscillation frequencies of high-order modes exhibit a similar trend of change. The radial displacements and pressure perturbations are largely influenced by the EOSs of crust region. {The frequency of the first excited state shows a strong linear relationship with both the slope and skewness parameters of the symmetry energy.} These findings suggest that the density dependence of the symmetry energy can be constrained through observations of neutron star radial oscillation frequencies.
nucl-thCPC(2025)·1 citation
12
Thermodynamics of fermionic excitations in heavy-quark QCD
Kei Tohme🇯🇵 · Takahiro M. Doi🇯🇵 · Masakiyo Kitazawa🇯🇵 · Krzysztof Redlich🇵🇱 · Chihiro Sasaki🇵🇱
We investigate the thermodynamic properties of fermionic excitations in heavy-quark QCD on the lattice with Wilson fermions. The grand potential is calculated analytically in the hopping parameter expansion (HPE) on the basis of the cumulant expansion. Using the grand potential, we compute the quark number susceptibilities and their ratios up to next-to-leading order in the HPE. The ratio of fourth- to second-order susceptibilities is shown to be unity (nine) in the deconfined (confined) phase at the leading order. Excitation properties of baryonic and quark modes in each phase are also investigated utilizing the Boltzmann statistics. We obtain an analytic formula for the quark excitation energy in the deconfined phase, while that for baryonic excitations in the confined phase is decomposed into flavor multiplets.
↳ hep-lathep-phhep-thnucl-thPRD(2025)·4 citations
13
Thermalization of Bottomonium in the Quark-Gluon Plasma
Nora Brambilla🇩🇪 · Tom Magorsch🇩🇪 · Antonio Vairo🇩🇪
We study the approach to equilibrium of bottomonium in the quark-gluon plasma within the open quantum system framework. We perform large-scale simulations of the long-time behavior in three dimensions using the quantum trajectory method to observe the emergence of steady states and determine the timescale of thermalization in position-, angular-momentum-, and color-space. We find that the thermalization timescale increases with decreasing temperature and decreasing coupling to the medium, which is given by transport coefficients of the medium. Additionally, we observe that the steady states exhibit small corrections to the Gibbs state due to medium interactions and show that these corrections diminish for weaker medium coupling and higher temperature. At a temperature of $450$ MeV, quarkonium relaxes to a state that is approximately thermal, with the most significant correction being a smaller overlap of the $1 S$ state with respect to the Gibbs state. We compare these findings with the master equation obtained at leading order in the expansion of the binding energy over the temperature, which we find to have a trivial steady state.
↳ hep-phnucl-exnucl-thJHEP(2026)·6 citations
14
Limitations in constraining neutron star radii and nuclear properties from inspiral gravitational wave detections
Zhenyu Zhu🇺🇸 · Richard O'Shaughnessy🇺🇸
We investigate the constraints on the neutron star equation of state (EoS) and nuclear properties achievable with third-generation gravitational wave detectors using the Fisher information matrix approach within the relativistic mean field (RMF) theory. Assuming an optimistic binary neutron star (BNS) merger rate, we generate simulated inspiral gravitational wave (GW) signals corresponding to one year of observation. From these simulated data, we compute the covariance matrix and posterior distributions for nuclear properties and EoS. Our results show that the EoS can be tightly constrained, particularly in the density range between one and four times nuclear saturation density. However, due to the scarcity of low-mass neutron stars in the GW sample, the EoS at sub-saturation densities remains poorly constrained. Thus, in turn, leads to weaker constraints on neutron star radii, as the radii are sensitive to the low-density EoS. Additionally, we present the expected correlations among nuclear parameters in general and plots of the inferred symmetry energy in particular, which represent degeneracies in their influence on the EoS and make them difficult to be constrained through GW observations alone. These highlights inherent limitations of inspiral GW signals in probing dense matter properties. Therefore, precise radius measurements, post-merger GW observations, and supplementary constraints from terrestrial nuclear experiments remain essential for a comprehensive understanding of dense matter.
↳ astro-ph.HEgr-qcnucl-thPRD(2026)·4 citations
15
In-medium heavy quark-antiquark $T$ -matrix without partial wave expansion
Anurag Tiwari🇨🇳 · Min He🇨🇳
The T-matrix of the heavy quark-antiquark ( $Q Q ˉ$ ) pair interacting through a screened Cornell potential in the quark-gluon plasma (QGP) is computed without employing the partial wave expansion. This is compared with the results obtained using the conventional method of partial wave expansion. Through a comprehensive survey over a range of screening mass and center-of-mass energy, which, when combined, determine the orbital angular momentum involved in the scattering through the associated force range and incident momentum, it is demonstrated that a substantial number of partial wave terms are necessary to precisely match the full scattering amplitude directly obtained from the method without partial wave expansion. For moderate screening masses (corresponding to one to two times the crossover transition temperature) and center-of-mass energy, the number of partial waves required for satisfactory matching turns out as large as 10-20, substantially larger than what one would expect based on simply measuring the magnitudes of the first few partial wave amplitudes. This highlights the efficiency of the new method in directly obtaining the full scattering amplitude needed for further computation of phenomenological observables. We also employ the new method to calculate the T-matrix at center-of-mass energies below the $Q Q ˉ$ mass threshold, and demonstrate the presence of bound states of different orbital quantum numbers simultaneously in a single energy scan.
↳ hep-phnucl-exnucl-thPRC(2026)·1 citation
16
Simulation of heavy quarkonium equilibration in the quark-gluon plasma
Shouxing Zhao🇨🇳 · Min He🇨🇳
We simulate the heavy quarkonium equilibration through transport in a static and homogeneous quark-gluon plasma (QGP) box within the semi-classical Boltzmann approach incorporating both the leading-order and next-to-leading-order dissociation and regeneration reactions. The scattering amplitudes involved are taken from perturbative computations based on effective color-electric dipole coupling of the heavy quarkonium with thermal gluons. By coupling the Langevin simulation of single heavy quark diffusion and the Boltzmann transport of the heavy quarkonium in a real-time fashion, we demonstrate how the kinetic and chemical equilibrium of heavy quarkonium with single heavy quarks in the medium is achieved in terms of both the bound state's yields and momentum distributions. The pertinent equilibration time turns out to be comparable to the lifetime of the QGP created in the most central heavy-ion collisions at the LHC energies. The role of the intricate interplay between the open and hidden heavy sector in the process of equilibration is highlighted. This work provides a dynamical way of understanding the phenomenological success of statistical hadronization model for charmonium production in relativistic heavy-ion collisions, and also paves the way for realistic phenomenological applications to heavy quarkonium transport.
↳ hep-phnucl-exnucl-thPRD(2025)·1 citation
17
Scaling behaviour of charged particles generated in Xe $-$ Xe collisions at $s_{NN}$ = 5.44 TeV using the AMPT model
Zarina Banoo🇮🇳 · Ramni Gupta🇮🇳 · Salman K. Malik🇮🇳 · Sheetal Sharma🇮🇳 · Fakhar Ul Haider🇮🇳 · Balwan Singh🇮🇳
The spatial configurations of particles produced in the kinematic phase space during a heavy-ion collision reflect the characteristics of the system created in the collision. The scaling behaviour of the multiplicity fluctuations is studied for the charged particles generated in Xe--Xe collisions at $s_{NN}$ ~=~5.44~TeV using the String Melting (SM) mode of the AMPT (A Multi-Phase Transport) model. The scaling behaviour of the normalized factorial moments ( $F_{q}$ ) gives significant information about the dynamics of the system under study. A linear power-law growth of the $F_{q}$ with the increasing phase space resolution, termed as intermittency, is investigated. The anomalous fractal dimension $D_{q}$ is determined, which is linked to the self-similarity and fractal nature of the particle emission spectra, whose dependence on the order of the moment ( $q$ ) is characterised by the intermittency index ( $φ_{q}$ ). Relating $q^{th}$ order Normalised Factorial Moment (NFM) with $F_{2}$ , the scaling exponent ( $ν$ ) is determined that quantifies the dynamics of the system created by these collisions and is analyzed for its dependence on the transverse momentum bin width ( $Δ p_{T}$ ). Results presented may be interpreted as model predictions and baseline expectations.
↳ hep-phhep-exnucl-thNPA(2026)·0 citations
18
Toward extracting scattering phase shift from integrated correlation functions V: complex $ϕ^{4}$ field model in $3 + 1$ dimensions
Peng Guo🇺🇸 · Frank X. Lee🇺🇸 · Andrei Alexandru🇺🇸
In Ref.~\cite{Guo:2024zal} and associated studies, a relativistic finite-volume formalism in $1 + 1$ dimensions is proposed to extract infinite-volume scattering phaseshift. It is based on the difference of integrated correlation functions (ICF) rather than energy spectrum in the finite volume, and can be regarded as complementary to the well-known Lüscher} formalism. In the present work, the formalism is further extended into $3 + 1$ dimensional spacetime. The aim is to explore and demonstrate the challenges in applying the formalism to more practical settings. Specifically, Monte Carlo simulations of a complex $ϕ^{4}$ relativistic field model are carried out in both 2+1 and 3+1 dimensions on lattices of varying sizes, and phaseshifts for the contact interaction are extracted from the formalism using modest computing resources.
↳ hep-lathep-phhep-thnucl-thPRD(2025)·4 citations
19
Polarized electromagnetic radiation by chiral media with time-dependent chiral chemical potential
Kirill Tuchin🇺🇸
We investigate photon production from media characterized by a time-dependent chiral chemical potential $μ_{5} (t)$ . We first consider the chiral anomaly as a small perturbation and show that $μ_{5} \to 2 γ$ process generates non-polarized radiation, as the probabilities of producing right and left-handed photons are equal. In chiral semimetal with a vanishing chiral chemical potential but a finite separation of Weyl nodes, $Δ (t)$ , the photon production vanishes at the leading order of perturbation theory. We then employ the method of Bogolyubov transformation to obtain the photon spectrum that sums up all powers of $μ_{5}$ . Employing the exactly solvable model $μ_{5} (t) \propto A + B tanh (t / τ)$ , we demonstrate that the spectrum exhibits strong circular polarization, whose direction is determined by the sign of $μ_{5}$ . The spectrum contains resonances associated with the instability of the electromagnetic field in chiral media. We discuss potential phenomenological applications of these findings.
↳ hep-phcond-mat.mtrl-scinucl-thPLB(2026)·5 citations

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