Nuclear Theory·nucl-th

Wednesday·March 26, 2025

11 papers—5 primary·6 cross-listed

01
[Submitted on 23 Mar 2025]
Tables of Neutron Thermal Cross Sections, Westcott Factors, Resonance Integrals, Maxwellian Averaged Cross Sections, Astrophysical Reaction Rates, and r-process Abundances Calculated from Evaluated Nuclear Data Libraries
B. Pritychenko
We present calculations of neutron thermal cross sections, Westcott factors, resonance integrals, Maxwellian-averaged cross sections, astrophysical reaction rates, and solar system $r$ -process abundances using the latest data from the major evaluated nuclear libraries for 849 ENDF target materials. The recent release of ENDF/B-VIII.1 library, progress in $^{252}$ Cf(SF) evaluation, extensive analysis of newly-evaluated neutron reaction cross sections, neutron covariances, and improvements in data processing techniques motivated us to calculate the nuclear industry and neutron physics parameters, produce $s$ -process Maxwellian-averaged cross sections and astrophysical reaction rates, extract $r$ -process abundances, systematically calculate uncertainties, and provide additional insights on currently available neutron-induced reaction data.
Comments:
165 pages, 5 figures, 31 tables
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2503.18990 [pdf]
Atom.Data Nucl.Data Tabl.(2025)·4 citations
02
[Submitted on 24 Mar 2025]
Spherical and Deformed Shell Effect Competition in Quasifission of Superheavy Nuclei
Richard Gumbel · Kyle Godbey
Quasifission, along with fusion-fission, represent the two most likely reaction outcomes to occur post-capture in collisions leading to superheavy nuclei. As such, understanding these mechanisms and how they relate to one another is key to understanding the intricate dynamics that drive the formation (or dissociation) of the nascent compound nuclei formed in fusion reactions. This understanding directly translates to a more informed picture of suitable reaction partners and can provide vital information for experimental efforts to study the physics and chemistry of superheavy elements. In this work we report results from time-dependent simulations of $^{48}$ Ca + $^{238}$ U and $^{50}$ Ti + $^{236}$ Th reactions at incident energies just above the Coulomb barrier with a focus on the quasifission process that prevent the formation of a fully equilibrated $^{286}$ Cn compound nucleus. We study these reactions systematically and consider a wide range of initial configurations to extract a robust estimate of primary fragment yields for the quasifission process. Multiple preferred exit channels are observed, with both spherical and deformed shell effects in the heavy and light fragments driving contributions to the production yields depending on the initial configuration of the system. Orientation effects of the deformed actinide targets are found to be a primary driver of which exit channels are populated. Furthermore, the impact of moving away from a doubly-magic projectile is explored with implications towards the reactions considered for current and future superheavy searches.
Comments:
6 pages, 4 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2503.19045 [pdf]
PRC(2025)·0 citations
03
[Submitted on 25 Mar 2025]
Deep learning approaches for nuclear binding energy prediction: a comparative study of RNN, GRU and LSTM Models
Amir Jalili · Feng Pan · Ai Xi Chen · Jerry P. Draayer
This study investigates the application of deep learning models-recurrent neural networks, gated recurrent units, and long short-term memory networks-for predicting nuclear binding energies. Utilizing data from the Atomic Mass Evaluation (AME2020), we incorporate key nuclear structure features, including proton and neutron numbers, as well as additional terms from the liquid drop model and shell effects. Our comparative analysis demonstrates that the gated recurrent units model achieves the lowest root-mean-square error ({\sigma}RMSE) of 0.326 MeV, surpassing traditional regression-based approaches. To assess model reliability, we validate predictions using the GarveyKelson relations, obtaining an error of 0.202 MeV, and further test extrapolation capabilities using the WS, WS3, and WS4 models. The extrapolation analysis confirms the robustness of our approach, particularly in predicting binding energies for nuclei near the driplines. These results highlight the effectiveness of deep learning in nuclear BE predictions, highlighting its potential to enhance the accuracy and reliability of theoretical nuclear models.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2503.19348 [pdf]
PRC(2025)·8 citations
04
[Submitted on 25 Mar 2025]
I-C-Q relations for rapidly rotating stable hybrid stars
Sujan Kumar Roy · Gargi Chaudhuri
A number of hadronic equations of state for neutron stars have been investigated for the purpose of the present paper, considering the fact that at sufficiently high density, heavy baryons and quark phases may appear. The observational limits from NICER, GW170817, etc., are obeyed by our choice of equations of state. The universal relations are investigated for both slowly and rapidly rotating neutron stars with heavy baryons present inside the core. For slowly rotating stars, the universality of the I-Love-Q relations is verified, and the I-C-Q relations are inferred to be universal for rapidly rotating stars. Further, we extend the investigation to obtain the universal relations for compact stars containing the quark core, where the connected stable branch of such hybrid stars is considered. The parameters of the I-Love-Q and I-C-Q universal relations are obtained for slowly rotating and rapidly rotating hybrid stars, respectively. These relations would enable extracting information, within the context of general relativity, from astrophysical systems involving rapidly rotating neutron stars.
Comments:
Accepted for publication in Astroparticle Physics
Subjects:
Nuclear Theory (nucl-th); General Relativity and Quantum Cosmology (gr-qc)
arXiv:
2503.19362 [pdf]
Astropart.Phys.(2025)·5 citations
05
[Submitted on 25 Mar 2025]
Quantum molecular dynamics model based on relativistic mean field theory for light nucleus fragmentation in hadron therapy
Akihiro Haga · Yoshi-hide Sato · Hana Fujiwara · Dousatsu Sakata · David Bolst · Edward C. Simpson · Susanna Guatelli
This study evaluates the accuracy of nuclear fragmentation simulations using a quantum molecular dynamics (QMD) model based on relativistic mean field (RMF) theory for an energy range of 50-400 MeV/u, relevant to hadron therapy. A total of 16 parameter sets within the RMF framework are assessed based on their ability to reproduce ground-state properties such as the mean squared radius and binding energy, as obtained in QMD simulations. Among these, the NS2 parameter set is identified as the most suitable for describing stable nuclei over a wide mass range, with the use of an adaptive Gaussian wave packet width. Fragmentation cross sections of carbon ion projectiles on light nuclei targets (H, C, O, Al, Ti, and Cu) are simulated at incident energies of 50, 95, 290, and 400 MeV/u and compared with experimental data. The results indicate that the RQMD.RMF model provides superior reproductions for fragmentation at lower energies (50 and 95 MeV/u) compared to the Light Ion QMD (LIQMD) model implemented in Geant4 version 11.2. At higher energies (290 and 400 MeV/u), the RQMD.RMF model performs comparably to the LIQMD. This study demonstrates that the RQMD.RMF model provides a reliable framework for analyzing nuclear fragmentation and holds potential for applications in the planning and quality assurance of hadron therapy.
Comments:
17 pages, 12 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2503.19395 [pdf]
PRC(2025)·1 citation
06
[Submitted on 24 Mar 2025] (cross-list from nucl-ex)
Comprehensive Review of 2 $β$ Decay Half-Lives
B. Pritychenko · V.I. Tretyak
The double-beta (2 $β$ )-decay is the rarest nuclear physics process, and its experimental half-lives (T $_{1/2}$ ) exceed the age of the Universe from nine to fourteen orders of magnitude. Double-beta decay was observed, and its half-life was measured in 14 parent nuclei using direct, radiochemical, and geochemical methods. The decay observables are analyzed using the Evaluated Nuclear Structure Data File (ENSDF) procedures, and the recommended T $_{1/2}$ were deduced. Using the calculated values of phase factors, the effective nuclear matrix elements were extracted and compared with available data. Thousands of theoretical and experimental works have been dedicated to these topics in the last 85 years, and we present two data sets of recommended values to encapsulate the results.
Comments:
63 pages, 16 figures, 6 tables
Subjects:
Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2503.19130 [pdf]
Atom.Data Nucl.Data Tabl.(2025)·15 citations
07
[Submitted on 25 Mar 2025] (cross-list from hep-ph)
Quark antenna in early stage anisotropic QCD matter
Joao Barata🇨🇭 · Carlos A. Salgado🇪🇸 · Joao M. Silva🇵🇹
The states of matter produced in the early stage of heavy ion collisions can be highly anisotropic. If such a feature is sufficiently pronounced, one should expect the final particle distribution inside jets to reflect it in the form of non-trivial angle correlations. In this talk, we discuss a first step in exploring such correlations by studying how a $q q ˉ$ state produced from an initial unpolarized gluon couples to the anisotropies of an underlying static QCD medium. The medium anisotropy is captured by allowing the jet quenching parameter to take different magnitudes in two orthogonal directions in the plane transverse to the jet axis. We find that the final particle distribution is sensitive to the medium anisotropy in the form of an azimuthal angle modulation, and more importantly, that this effect couples directly to the helicity/spin of the final states, offering a novel way to extract the details of the underlying matter which is not accessible with standard jet observables. We further show how such features can be extracted from the Fourier decomposition of the distribution and from final state transverse spin polarization measurements.
Comments:
8 pages, 6 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2503.19224 [pdf]
EPJ Web Conf.(2025)·1 citation
08
[Submitted on 25 Mar 2025] (cross-list from physics.atom-ph)
Atomic determination of the nuclear quadrupole moment $Q (^{209} Bi)$ using the multi-configuration Dirac-Hartree-Fock method
Jiguang Li · Jacek Bieroń · Michel Godefroid · Per Jönsson
The multiconfiguration Dirac-Hartree-Fock method implemented in the Grasp2018 package was employed to calculate the magnetic dipole hyperfine interaction constants and electric field gradients of levels in the ground configuration of the neutral bismuth atom. Combining the calculated electric field gradient of the ground state with the measured electric quadrupole hyperfine interaction constant, we extracted the nuclear quadrupole moment for the $^{209}$ Bi isotope, $Q (^{209} Bi) = - 422 (22)$ ~mb. This value, together with other results obtained from atomic- and molecular-structure calculations, created the ``world average" nuclear quadrupole moment of this isotope, $Q (^{209} Bi) = - 420 (17)$ ~mb.
Subjects:
Atomic Physics (physics.atom-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2503.19488 [pdf]
Eur.Phys.J.D(2025)·0 citations
09
[Submitted on 25 Mar 2025] (cross-list from hep-ph)
Strongly Interacting Dark Matter admixed Neutron Stars
Yannick Dengler🇦🇹 · Suchita Kulkarni🇦🇹 · Axel Maas🇦🇹 · Kevin Radl🇦🇹
Dark matter may accumulate in neutron stars given its gravitational interaction and abundance. We investigate the influence of strongly-interacting dark matter, described by a QCD-like one-flavor $G_{2}$ gauge theory, on neutron stars. This choice allows to test, for the first time, a first-principles-determined non-Abelian dark matter equation of state, which supports composite fermionic dark matter and thus a Fermi-pressure-stabilized dark matter component. The ordinary matter part of the mixed star is described by available model-agnostic equations of state that interpolate between the low-density regime and high-density regime. We find that strongly-interacting dark matter has a similar impact on neutron stars as other model equation of states and confirm that strongly-interacting dark matter can be accommodated by constraints from neutron star observations within our uncertainties.
Comments:
29 pages, 11 figures; v4: Minor modifications v3: Substantially improved figures with more comparisons to observational data, various minor improvements in the text v2: Added appendix with technical details, various improvements and minor changes
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2503.19691 [pdf]
SciPost Phys.Core(2026)·7 citations
10
[Submitted on 25 Mar 2025] (cross-list from hep-ph)
Exploring Efimov states in $D^{*} D^{*} D^{*}$ and $D D^{*} D^{*}$ three-body systems
Hai-Long Fu🇨🇳 · Yong-Hui Lin🇩🇪 · Feng-Kun Guo🇨🇳 · Hans-Werner Hammer🇩🇪 · Ulf-G. Meißner🇨🇳 · Akaki Rusetsky🇩🇪 · Xu Zhang🇨🇳
The Efimov effect is an intriguing three-body quantum phenomenon. Searching for Efimov states within the realms of nuclear and hadronic physics presents a challenge due to the inherent inability of natural physical systems to exhibit adjustable two-body scattering lengths. In this study, we examine the potential existence of Efimov states in the $D^{*} D^{*} D^{*}$ and $D D^{*} D^{*}$ three-hadron systems. Utilizing a pionless effective field theory framework, we determine that the presence of Efimov states in the spectrum of the $D^{*} D^{*} D^{*}$ system is contingent upon the existence of an $(I, J) = (1, 2)$ $D^{*} D^{*}$ two-body bound system. If only the $T_{cc}^{+}$ and its heavy quark spin partner $T_{cc}^{*+}$ exist while there is no near-threshold pole in all other $S$ -wave $D^{(*)} D^{*}$ scattering amplitudes, no Efimov effect is expected in the $D^{(*)} D^{*} D^{*}$ systems.
Comments:
25 pages, 8 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2503.19709 [pdf]
JHEP(2025)·10 citations
11
[Submitted on 25 Mar 2025] (cross-list from hep-ph)
The role of chiral symmetry and the non-ordinary $κ / K_{0}^{*} (700)$ nature in $π^{\pm} K_{S}$ femtoscopic correlations
Miguel Albaladejo🇪🇸 · Alejandro Canoa🇪🇸 · Juan Nieves🇪🇸 · Jose Ramón Peláez🇪🇸 · Enrique Ruiz-Arriola🇪🇸 · Jacobo Ruiz de Elvira🇪🇸
We show that the use of realistic $π K$ interactions, obtained from a dispersive analysis of scattering data, as well as relativistic corrections, are essential to describe recently observed $π^{\pm} K_{S}$ femtoscopic correlations. We demonstrate that the spontaneous chiral symmetry breaking dynamics and the non-ordinary features of the $κ / K_{0}^{*} (700)$ resonance, together with large cancellations between isospin channels, produce a large suppression of $π^{\pm} K_{S}$ femtoscopic correlations compared to widely used models. Within an improved version of the standard on-shell factorization formalism, we illustrate that compensating for this interaction suppression leads to source radii smaller than 1 fm, contrary to usual expectations, as well as larger correlation strengths. The relation between these two parameters cannot be accommodated within naive models describing the nature of the resonances. This may raise concerns about the applicability of popular but too simple approaches for systems with light mesons. However, the correlation-suppression effects we demonstrate here will be relevant in any formalism, and substantial corrections may be expected for other femtoscopic systems involving light mesons.
Comments:
5 pages, 5 figures. v2: minor edits to match journal version
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Theory (nucl-th)
arXiv:
2503.19746 [pdf]
PLB(2025)·13 citations

Affiliations

first authorsco-authorsvia INSPIRE