Nuclear Theory·nucl-th

Tuesday·May 21, 2024

15 papers—10 primary·5 cross-listed

01
[Submitted on 17 May 2024]
The Quark Pauli Principle and the Transmutation of Nuclear Matter
Larry McLerran🇺🇸 · Gerald A. Miller🇺🇸
The phase space density, $ρ^{Q}$ , of quarks in nuclei is studied using realistic models of unintegrated quark distributions, known as transverse momentum densities (TMDs). If this density exceeds unity for matter at normal nuclear densities, the effects of the quark Pauli principle must play a role in nuclei, and models in which the nucleon density at low momentum is small (Quarkyonic matter) may become a starting point for an entirely new description of nuclei. We denote the nuclear density for which $ρ^{Q} = 1$ to be a transmutation density, $n_{T}$ , because quark degrees of freedom must be relevant at that density. Including the TMDs of [G. de Teramond et. al, \href{DOI:https://doi.org/10.1103/PhysRevLett.120.182001} Phys. Rev. Lett. {\bf 120}, 182002, (2018)] for the valence quarks and phenomenological TMDs for the sea quarks we find that $n_{T} = 0.17 \pm 0.04 f m^{- 3}$ , the density of normal nuclear matter. Some of fhe implications of this finding are discussed.
Comments:
10 pages, 1 figures,
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
2405.11074 [pdf]
PRC(2024)·18 citations
02
[Submitted on 18 May 2024]
Random close packing of binary hard spheres favors the stability of neutron-rich atomic nuclei
Carmine Anzivino · Vinay Vaibhav · Alessio Zaccone
In spite of the success of the Bethe-Weizsäcker mass formula in its modern numerical and predictive implementations, the common-knowledge principle that it is electrostatics which, ultimately, favors neutron-rich nuclei still presents unclear aspects. For example, while it is true that the Coulomb interaction promotes the tendency towards neutron-rich nuclei, the opposite effects of Majorana exchange forces and Pauli exclusion are known to counteract this tendency. We show that a recent analytical progress in the mathematical description of random close packing of spheres with different sizes provides a missing contribution to the theoretical description of the $Z$ versus $N$ slope in the nuclides chart. In particular, the theory suggests, on geometric grounds and with a physically-reasoned assumption that the excluded-volume size of neutrons is 20\% larger than that of protons, that the most stable nuclei are those with ratio $Z / N \approx 0.75$ . This new ``geometric'' random-packing contribution to the semi-empirical mass formula may be the missing aspect of nuclear structure that tilts the balance towards neutron-rich nuclei in the Segrè stability chart.
Subjects:
Nuclear Theory (nucl-th); cond-mat.dis-nn (cond-mat.dis-nn); Statistical Mechanics (cond-mat.stat-mech); High Energy Physics — Theory (hep-th); Nuclear Experiment (nucl-ex)
arXiv:
2405.11268 [pdf]
2 citations
03
[Submitted on 18 May 2024]
Fox's H-Functions: A Gentle Introduction Through Astrophysical Thermonuclear Functions
Hans J. Haubold · Dilip Kumar · Ashik A. Kabeer
Needed for cosmological and stellar nucleosynthesis, we are studying the closed-form analytic evaluation of thermonuclear reaction rates. In this context, we undertake a comprehensive analysis of three distinct velocity distributions, namely the Maxwell-Boltzmann distribution, the pathway distribution, and the Mittag-Leffer distribution. We emphasize the utilization of Meijer G-function and Fox H-function which are special functions of mathematical physics.
Comments:
8 pages
Subjects:
Nuclear Theory (nucl-th); Cosmology and Nongalactic Astrophysics (astro-ph.CO); Solar and Stellar Astrophysics (astro-ph.SR)
arXiv:
2405.11325 [pdf]
Axioms(2024)·0 citations
04
[Submitted on 19 May 2024]
Production of light nuclei in isobaric Ru+Ru and Zr+Zr collisions at $s_{NN}$ =7.7-200 GeV from a multiphase transport model
Fei Li🇨🇳 · Song Zhang🇨🇳 · Kai-Jia Sun🇨🇳 · Yu-Gang Ma🇨🇳
The production of light nuclei in isobaric $_{44}^{96}$ Ru + $_{44}^{96}$ Ru and $_{40}^{96}$ Zr + $_{40}^{96}$ Zr collisions, ranging from $s_{N N}$ = 7.7 to 200 GeV, are studied using the string melting version of A Multi Phase Transport (AMPT) model in combination with a coalescence approach to light nuclei production. From the calculated yields, transverse momentum $p_{T}$ spectra, and rapidity dependences of light nuclei $p$ , $n$ , $d$ , $t$ , $^{3}$ He, we find that the Ru+Ru/Zr+Zr ratios for the yields of these particles exceed unity with the inclusion of a quadrupole deformation $β_{2}$ and octupole deformation $β_{3}$ as well as the neutron skins. We also find that heavier particles have a larger deviation from unity. Furthermore, we find that as the collision energy increases, the influence of isospin effects on the production of light nuclei in isobar collisions gradually decreases, while the influence of nuclear structure becomes more significant, particularly evident from the energy dependence of the deuteron ratio, which is unaffected by isospin effects.
Comments:
9 pages, 5 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2405.11558 [pdf]
PRC(2024)·5 citations
05
[Submitted on 19 May 2024]
Investigation of suppression of $Υ (n S)$ in relativistic heavy-ion collisions at RHIC and LHC energies
Junlee Kim🇨🇭 · Jaebeom Park🇺🇸 · Byungsik Hong🇰🇷 · Juhee Hong🇰🇷 · Eun-Joo Kim🇰🇷 · Yongsun Kim🇰🇷 · MinJung Kweon🇰🇷 · Su Houng Lee🇰🇷 · Sanghoon Lim🇰🇷 · Jinjoo Seo🇩🇪
The primary purpose of studying quarkonium production in relativistic heavy-ion collisions is to understand the properties of the quark-gluon plasma. At various collision systems, measurements of quarkonium states of different binding energies, such as $Υ (n S)$ , can provide comprehensive information. A model study has been performed to investigate the modification of $Υ (n S)$ production in Pb-Pb collisions at $s_{NN} =$ 5.02 TeV and Au-Au collisions at $s_{NN} =$ 200 GeV. The Monte-Carlo simulation study is performed with a publicly available hydrodynamic simulation package for the quark-gluon plasma medium and a theoretical calculation of temperature-dependent thermal width of $Υ (n S)$ considering the gluo-dissociation and inelastic parton scattering for dissociation inside the medium. In addition, we perform a systematic study with different descriptions of initial collision geometry and formation time of $Υ (n S)$ to investigate their impacts on yield modification. The model calculation with a varied parameter set can describe the experimental data of $Υ (n S)$ in Pb-Pb collisions at 5.02 TeV and $Υ (2 S)$ in Au-Au collisions at 200 GeV but underestimates the modification of $Υ (1 S)$ at the lower collision energy. The nuclear absorption mechanism is explored to understand the discrepancy between the data and simulation.
Comments:
9 pages, 11 figures
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2405.11689 [pdf]
PRC(2025)·1 citation
06
[Submitted on 20 May 2024]
High energy nucleus-nucleus collisions with accounting for Coulomb interaction
Yu.M. Shabelski🇷🇺 · A.G. Shuvaev🇷🇺
The differential elastic cross sections of $^{12}$ C - $^{12}$ C, $^{16}$ O - $^{16}$ O and $^{20}$ Ne - $^{20}$ Ne nuclei scattering are calculated in the complete Glauber theory with the account of the modification due to Coulomb interaction and form factor effects. The role of the Coulomb interaction is shown to be significant mainly in the diffractive minima. The results of the complete Coulomb calculations are noticeably different from those obtained in the Born approximation.
Comments:
9 pages, 3 figures
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2405.11842 [pdf]
Mod.Phys.Lett.A(2026)·0 citations
07
[Submitted on 20 May 2024]
Analysis of $^{115}$ In $β$ decay through the spectral moment method
Joel Kostensalo🇫🇮 · Eligio Lisi🇮🇹 · Antonio Marrone🇮🇹 · Jouni Suhonen🇫🇮
We analyze the $^{115}$ In $β$ -decay energy spectrum through the spectral moment method (SMM), previously introduced in the context of $^{113}$ Cd $β$ decay. The spectral moments $μ_{n}$ are defined as averaged $n^{th}$ powers of the $β$ particle energy, characterizing the spectrum normalization ( $n = 0$ ) and shape ( $n \geq 1$ ) above a given threshold. For $^{115}$ In, we consider three independent datasets characterized by different thresholds. We also consider three nuclear model calculations with two free parameters: the ratio of axial-vector to vector couplings, $r = g_{A} / g_{V}$ , and the small vector-like relativistic nuclear matrix element (NME), $s = s$ -NME. By using the most recent of the three datasets, we show that the first few spectral moments can determine $(r, s)$ values in good agreement with those obtained by full-fledged experimental fits. We then work out the SMM results for the other datasets. We find that, although $g_{A}$ quenching is generally favored, the preferred quenching factors may differ considerably depending on the chosen experimental data and nuclear models. We discuss various issues affecting both the overall normalization and the low-energy behaviour of the measured and computed spectra, and their joint effects on the experimentally quoted half-life values. Further $^{115}$ In $β$ -decay data at the lowest possible energy threshold appear to be crucial to clarify these issues.
Comments:
14 pages, including 8 figures
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Experiment (hep-ex); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
2405.11920 [pdf]
PRC(2024)·5 citations
08
[Submitted on 20 May 2024]
Deciphering Hypertriton and Antihypertriton Spins from Their Global Polarizations in Heavy-Ion Collisions
Kai-Jia Sun🇨🇳 · Dai-Neng Liu🇨🇳 · Yun-Peng Zheng🇨🇳 · Jin-Hui Chen🇨🇳 · Che Ming Ko🇺🇸 · Yu-Gang Ma🇨🇳
Understanding the properties of hypernuclei is crucial for constraining the nature of hyperon-nucleon ( $Y - N$ ) interactions, which plays a key role in determining the inner structure of compact stars. The lightest hypernuclei and antihypernuclei are the hypertriton ( $_{Λ}^{3} H$ ), which consists of a pair of nucleons and a $Λ$ hyperon, and its antinucleus ( $_{Λ ˉ}^{3} H$ ). Significant knowledge has recently been acquired regarding the mass, lifetime, and binding energy of $_{Λ}^{3} H$ . However, its exact spin, whether $\frac{1}{2}$ or $\frac{3}{2}$ , remains undetermined in both experimental and theoretical studies. Here, we present a novel method of using the hypertriton global polarization in heavy-ion collisions to decipher not only its total spin but also its internal spin structure. This method is based on the finding that its three different spin structures exhibit distinct beam energy dependence of its global polarization when it is produced in these collisions from the coalescence of proton, neutron and $Λ$ . Future observations of the hypertriton and antihypertriton global polarizations thus provide the opportunity to unveil the spin structures of hypertriton and antihypertriton and their production mechanisms in heavy-ion collisions.
Comments:
Accepted by Physics Review Letters. (6 pages and 2 figures)
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2405.12015 [pdf]
1 citation
09
[Submitted on 20 May 2024]
On model emulation and closure tests for 3+1D relativistic heavy-ion collisions
Hendrik Roch🇺🇸 · Syed Afrid Jahan🇺🇸 · Chun Shen🇺🇸
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.
Comments:
21 pages, 13 figures
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2405.12019 [pdf]
PRC(2024)·14 citations
10
[Submitted on 20 May 2024]
$^{164} Pb$ : A possible heaviest $N = Z$ doubly magic nucleus
Tomoya Naito · Masaaki Kimura · Masaki Sasano
We confirm by using the Skyrme Hartree-Fock-Bogoliubov calculation that $^{164} Pb$ is a possible heaviest $N = Z$ doubly magic nucleus whose lifetime is long enough to be measured on accelerator experiments. We estimate the proton-emission and alpha-decay half-lives of $^{164} Pb$ . The estimated proton-emission half-life ranges from $0.1 ps$ to $10 ns$ , while the alpha decay can be safely neglected.
Comments:
9 pages, 8 figures, 3 tables
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2405.12095 [pdf]
PRResearch(2025)·3 citations
11
[Submitted on 17 May 2024] (cross-list from cond-mat.mtrl-sci)
Magnetic Weyl semimetals as a source of circularly polarized THz radiation
Jeremy Hansen · Kazuki Ikeda · Dmitri E. Kharzeev · Qiang Li · Kirill Tuchin
We propose to use the electromagnetic radiation induced by a few MeV electron beam in magnetic Weyl semimetals as a source of the circularly polarized photons in the THz frequency range.
Subjects:
cond-mat.mtrl-sci (cond-mat.mtrl-sci); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2405.11076 [pdf]
Phys.Open(2025)·7 citations
12
[Submitted on 18 May 2024] (cross-list from hep-ph)
Revisiting $O (N)$ $σ$ model at unphysical pion masses and high temperatures. II. The vacuum structure and thermal $σ$ pole trajectory with cross-channel improvements
Yuan-Lin Lyu🇨🇳 · Qu-Zhi Li🇨🇳 · Zhiguang Xiao🇨🇳 · Han-Qing Zheng🇨🇳
The effective potential of the $O (N)$ model at large $N$ limit is reinvestigated with varying pion mass and temperature. For large pion masses and high temperatures, we find the phenomenologically favored vacuum, located on the upper branch of the double-branched effective potential for physical $m_{π}$ , moves to the lower branch and becomes no longer a local minimum but a saddle point. The existence and running of the tachyon pole are also discussed. These phenomena indicate that the applicable energy range of $O (N)$ model is more and more limited as $m_{π}$ becoming larger and temperature going higher. With the effective coupling constant defined from the effective potential, the possible correspondence between the two branches of the effective potential and the two phases of the theory (distinguished by positive or negative coupling) is verified even with nonzero explicit symmetry breaking and at finite temperature. Also, we generalize the $N / D$ modified $O (N)$ model to study the thermal trajectory of the $σ$ pole with the cross-channel contributions considered and find the thermal $σ$ pole trajectory resembles its counterpart with varying pion mass at zero temperature.
Comments:
v1: 15 pages, 14 figures; v2: 17 pages, 14 figures, references and some details added; v3: 18 pages, 16 figures, published version
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Lattice (hep-lat); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2405.11313 [pdf]
PRD(2024)·5 citations
13
[Submitted on 20 May 2024] (cross-list from astro-ph.HE)
Magnetar QPOs and neutron star crust elasticity
Hajime Sotani
The crust region is a tiny fraction of neutron stars, but it has a variety of physical properties and plays an important role in astronomical observations. One of the properties characterizing the crust is the elasticity. In this review, with the approach of asteroseismology, we systematically examine neutron star oscillations excited by crust elasticity, adopting the Cowling approximation. In particular, by identifying the quasi-periodic oscillations observed in magnetar flares with the torsional oscillations, we make a constraint on the nuclear saturation parameters. In addition, we also discuss how the shear and interface modes depend on the neutron star properties. Once one detects an additional signal associated with neutron star oscillations, one can get a more severe constraint on the saturation parameters and/or neutron star properties, which must be a qualitatively different constraint obtained from terrestrial experiments, and help us to complementarily understand astrophysics and nuclear physics.
Comments:
Accepted for publication in Universe: Feature Papers 2024 - Compact Objects
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2405.11858 [pdf]
Universe(2024)·19 citations
14
[Submitted on 20 May 2024] (cross-list from hep-ph)
Pole structure of $P_{ψ}^{N} (4312)^{+}$ via machine learning and uniformized S-matrix
Leonarc Michelle Santos🇵🇭 · Vince Angelo A. Chavez🇵🇭 · Denny Lane B. Sombillo🇵🇭
We probed the pole structure of the $P_{ψ}^{N} (4312)^{+}$ using a trained deep neural network. The training dataset was generated using uniformized independent S-matrix poles to ensure that the obtained interpretation is as model-independent as possible. To prevent possible ambiguity in the interpretation of the pole structure, we included the contribution from the off-diagonal element of the S-matrix. Five out of the six neural networks we trained favor $P_{ψ}^{N} (4312)^{+}$ as possibly having a three-pole structure, with one pole on each of the unphysical sheets - a first in its report. The two poles can be associated to a pole-shadow pair which is a characteristic of a true resonance. On the other hand, the last pole is most likely associated with the coupled-channel effect. The combined effect of these poles produced a peak below the $Σ_{C}^{+} D ˉ^{0}$ which mimic the line shape of a hadronic molecule.
Comments:
11 pages, 4 figures, 7 tables
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2405.11906 [pdf]
J.Phys.G(2025)·13 citations
15
[Submitted on 20 May 2024] (cross-list from gr-qc)
Micro-cosmos model of a nucleon
Michael Cramer Andersen🇩🇰
This study explores the age-old quest to construct a geometric model of a quantum particle. While static classical particle models have largely been dismissed, the focus has now shifted to intricate dynamic models that hold the promise of reconciling general relativity with quantum mechanics. We propose that matter particles can be described as radiation confined within dynamically curved spacetime regions, without the need for quantization of space and time, and using standard field equations and natural Planck units. Specifically, we investigate a cyclic or oscillating radiation-dominated micro cosmos undergoing repeated bouncing. Our methodology employs integration, with carefully defined initial conditions. The results include several observable properties characteristic of quantum particles. We calculate the total mass, revealing a compelling inverse proportionality between mass and radius identical with the de Broglie relationship. Applying this model to protons, we discover a profound and surprisingly simple relationship between the proton's radius and mass expressed in Planck units. This enables a definition of the proton radius that aligns remarkably well with the 2018 CODATA value. Furthermore, our analysis demonstrates that the radial density profile of the proton (or nucleon), averaged over a cycle time, increases toward the center. The problem of embedding the micro cosmos within a background spacetime is also described. These results underscore the relevance of general relativity in the domain of nuclear physics. Moreover, the model offers a fresh perspective that can stimulate new ideas in the ongoing quest to unify general relativity with quantum physics.
Comments:
18 pages, 5 figures
Subjects:
General Relativity and Quantum Cosmology (gr-qc); Nuclear Theory (nucl-th)
arXiv:
2405.12049 [pdf]
Mod.Phys.Lett.A(2024)·0 citations

Affiliations

first authorsco-authorsvia INSPIRE