Nuclear Theory·nucl-th

Friday·September 12, 2025

11 papers—9 primary·2 cross-listed

01
[Submitted on 10 Sept 2025]
Attractor of hydrodynamic attractors
Shile Chen🇨🇳 · Shuzhe Shi🇨🇳
Understanding how hydrodynamics emerges rapidly in the medium produced by relativistic heavy-ion collisions remains a key theoretical challenge. While the attractor solution -- manifesting as a non-thermal fixed point during the early evolution stage -- offers a potential explanation, it does not fully account for how far-from-equilibrium systems quickly approach near-equilibrium states. In this Letter, we demonstrate that the attractor in a higher-order hydrodynamic theory converges to the same solution as a second-order theory before reaching the Navier--Stokes limit. This finding suggests that commonly used second-order hydrodynamic equations, provided they incorporate the correct transport coefficients, are adequate to approximate the system's behavior starting from an intermediate time -- even when using a higher-order theory that would be more suitable for describing the far-from-equilibrium evolution.
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2509.08864 [pdf]
PRD(2026)·4 citations
02
[Submitted on 10 Sept 2025]
Estimation of deuteron binding energy with renormalization group-based effective interactions using the variational quantum eigensolver
Sreelekshmi Pillai🇮🇳 · S. Ramanan🇮🇳 · V. Balakrishnan🇮🇳 · S. Lakshmibala🇮🇳
We have obtained the energy of the deuteron on a quantum simulator using the variational quantum eigensolver. We have employed realistic two-body interactions, namely, chiral N4LO and AV $_{18}$ , thus incorporating the role of tensor forces. These interactions are subsequently evolved to low resolution scales using the similarity renormalization group approach with parameter $λ$ . The deuteron ground state energy has been calculated in the truncated harmonic oscillator basis, using the Qiskit-Aer simulator in both noise-free and noisy cases. The noise models have been taken from the actual IBM quantum hardware, and the results obtained have been extrapolated to the zero noise limit. The number of harmonic oscillator basis states (hence qubits) needed for computing the energy to within 1 percent of the experimental value in the quantum simulator, decreases with decreasing $λ$ . We have analysed the extent of entanglement between oscillator modes using concurrence as the entanglement quantifier. It is seen that the entanglement decreases as $λ$ is lowered from the bare value to $\sim 1.0 fm^{- 1}$ independent of the form of the bare interaction and the number of harmonic oscillator basis states.
Comments:
Revised version corresponding to the published article
Subjects:
Nuclear Theory (nucl-th); Quantum Physics (quant-ph)
arXiv:
2509.08948 [pdf]
Phys.Scripta(2026)·1 citation
03
[Submitted on 10 Sept 2025]
Monte Carlo Simulation of Spallation and Fission Fragment Distributions for ADS-Related Nuclear Reactions
Sun Wenming
Monte Carlo simulations with the CRISP code were conducted to study spallation and fission fragment distributions induced by intermediate- and high-energy protons and photons on actinide and pre-actinide nuclei. The model accounts for intranuclear cascade, pre-equilibrium, and evaporation-fission competition, enabling consistent treatment of both residues and fission products. Comparisons with experimental data show good agreement in mass and charge distributions, with minor deviations for light fragments. The results highlight the reliability of Monte Carlo approaches for predicting residual nuclei and fragment yields under accelerator-driven system (ADS) conditions. This work provides nuclear data relevant to ADS design, safety, and transmutation analysis
Comments:
A total of 9 pages, 28 images, and 4 tables
Subjects:
physics.gen-ph (physics.gen-ph)
arXiv:
2509.08996 [pdf]
1 citation
04
[Submitted on 10 Sept 2025]
Assessing background effects in search of the chiral vortical effect in relativistic heavy-ion collisions
Chunzheng Wang🇨🇳 · Jie Wan🇨🇳 · Jinfeng Liao🇨🇳 · Yugang Ma🇨🇳 · Shuzhe Shi🇨🇳 · Qiye Shou🇨🇳 · Zhengqing Wang🇨🇳 · Kegang Xiong🇨🇳 · Song Zhang🇨🇳 · Liang Zheng🇨🇳
The search for the Chiral Vortical Effect (CVE) in relativistic heavy-ion collisions is carried out by measuring azimuthal correlators for baryon pairs such as $Λ$ and protons. Experimental results from the ALICE collaboration show significant separations in these observables, however, the interpretation remains unclear. It is believed that background contributions from baryon production mechanisms may play an important role. Using three phenomenological models, the Blast Wave, AMPT, and AVFD+UrQMD, we systematically investigate the background effects in Pb--Pb collisions at \snn = 5.02 TeV. We demonstrate that local baryon conservation, as well as hadronic annihilation processes, can significantly influence the correlators. The feed-down contribution from secondary protons is also estimated. Our study provides a foundation for disentangling background mechanisms and further facilitates the search for the CVE.
Comments:
9 pages, 4 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2509.09025 [pdf]
PLB(2026)·1 citation
05
[Submitted on 10 Sept 2025]
Study on the equation-of-state with light clusters and hypernuclei
Elena Bratkovskaya🇩🇪 · Jörg Aichelin🇫🇷
Heavy-ion collision experiments offer a unique opportunity to explore the early stages of the Universe by creating matter under extreme conditions of high temperature and baryon density. The properties of such matter are governed by the equation-of-state (EoS), which remains a central focus of investigation from both experimental and theoretical perspectives. Flow harmonics are among the most sensitive observables for probing the EoS, as they strongly reflect the underlying interactions and degrees of freedom of the system. In this article, we review the current status of our understanding of the EoS based on microscopic transport models, emphasizing comparisons with experimental data in the few GeV energy range.
Comments:
19 pages, 22 figures, review for the EPJ Special Topic "Exploring Dense Nuclear Matter"
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2509.09061 [pdf]
Eur.Phys.J.ST(2026)·4 citations
06
[Submitted on 11 Sept 2025]
Scaling approach to rigid and soft nuclear deformation through flow fluctuations in high-energy nuclear collisions
Lumeng Liu🇨🇳 · Chunjian Zhang🇨🇳 · Jinhui Chen🇨🇳 · Jiangyong Jia🇺🇸 · Xu-Guang Huang🇨🇳 · Yu-Gang Ma🇨🇳
The nature of octupole deformation, whether static or vibrational, remains an open question in nuclear physics. Here, we propose a scaling approach to probe this ambiguity by triangular flow fluctuations using multi-particle cumulants, $c_{3, ε} {4}$ , in relativistic $^{238}$ U+ $^{238}$ U collisions. We demonstrate that both $∣ c_{3, ε} {4} ∣$ and the ratio $∣ c_{3, ε} {4} / c_{3, ε}^{2} {2} ∣$ scale linearly with the fourth-order moment of octupole deformation, $⟨ β_{3, U}^{4} ⟩$ . Combined with the known linear relation of $c_{3, ε} {2}$ to $⟨ β_{3, U}^{2} ⟩$ , this new relation provides a direct extraction of both the mean and variance of the octupole deformation fluctuations, finally discriminating between static and dynamic origins. This work establishes a new tool to probe the static and dynamic collective modes in high-energy nuclear collisions, advancing a significant step toward refining the initial conditions of quark-gluon plasma.
Comments:
8 Pages, 4 figures
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2509.09376 [pdf]
PLB(2026)·8 citations
07
[Submitted on 11 Sept 2025]
The role of near neutron drip-line nuclei in the $r$ -process
T. Yu · Y. Y. Guo · X. F. Jiang · X. H. Wu
The role of near neutron-drip-line nuclei in the rapid neutron-capture process ( $r$ -process) is studied with the classical $r$ -process model. Simulations under different astrophysical conditions ( $T$ , $n_{n}$ ) show that $r$ -process paths approach the neutron-drip line under low-temperature and high-neutron-density conditions. A sensitivity study reveals that variations in the nuclear masses of these exotic nuclei significantly impact the abundances of superheavy nuclei, and lead to obvious abundance variations in the $A = 110 - 125$ , $A = 175 - 185$ , and $A = 200 - 205$ regions. By contrast, the $r$ -process rare-earth peak and the $A = 130, 195$ peaks remain largely unaffected. The nuclei that obviously impact $r$ -process abundances are mainly distributed in the region of $25 \leq Z \leq 90$ and $50 \leq N \leq 180$ , with the nuclei around neutron magic numbers found to be particularly important for the $r$ -process, even in the near-neutron-drip-line region.
Comments:
8 pages, 7 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2509.09478 [pdf]
CPC(2026)·0 citations
08
[Submitted on 11 Sept 2025]
From wave-function to fireball geometry: the role of a restored broken symmetry in ultra-relativistic collisions of deformed nuclei
Weiyao Ke🇨🇳
Traditional Monte Carlo (MC) Glauber models treat the shapes of deformed nuclei classically; that is, in a collision event, each nucleus is randomly assigned a configuration with fixed deformation parameters and orientation (collective coordinates). Quantum mechanically, however, a valid nuclear ground state must be a superposition of these configurations to preserve rotational symmetry, creating entanglement in the nucleon wave function. We show that for collisions with a moderate number of participants, this quantum superposition -- particularly in the orientation of deformed nuclei -- has non-negligible impacts on the initial geometry of the quark-gluon plasma fireball. We propose a minimal extension to the MC Glauber model to approximately incorporate these superposition effects and find a $6$ - $8%$ reduction in the second-order eccentricity in central Ne-Ne and Ne-Pb collisions relative to results from classical treatments of nuclear orientation. Though these effects are expected to be small for large collision systems such as U-U, this study demonstrates the importance of properly accounting for quantum superposition and the associated off-diagonal information when studying nuclear deformation in ultra-relativistic nuclear collisions.
Comments:
7 pages, 4 figures. Changes: shorter and more concise, an appendix for details, adding more refs including most recent experimental results
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2509.09549 [pdf]
14 citations
09
[Submitted on 11 Sept 2025]
Algebraic treatment of alpha-cluster nuclei
Roelof Bijker · Omar Alejandro Díaz Caballero
In this contribution we review the algebraic cluster model (ACM) for $α$ -cluster nuclei with $A = 4 k$ nucleons and its extension to the cluster shell model (CSM) for $A = 4 k + x$ nuclei. Particular attention is paid to the question to what extent the $α$ -cluster structure survives under the addition of extra nucleons. As an example, we discuss the properties of $^{12}$ C and $^{13}$ C.
Comments:
8 pages, 7 figures, 1 table, to be published in EPJ Web of Conferences, Proceedings of 14th Spring Seminar on Nuclear Physics: Cutting-edge developments in Nuclear Structure Physics, May 19-23, Ischia, Italy
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2509.09634 [pdf]
EPJ Web Conf.(2025)·0 citations

Affiliations

first authorsco-authorsvia INSPIRE