Nuclear Theory·nucl-th

Friday·August 1, 2025

14 papers—9 primary·5 cross-listed

10
[Submitted on 29 Jul 2025] (cross-list from physics.atom-ph)
Heavy flavored hydrogen molecule systems
Hui-Min Yang · Yao Ma · Shi-Lin Zhu
This study provides a comprehensive analysis of $S$ -wave exotic hydrogen-like three-body systems ( $pp μ^{-}$ , $pp τ^{-}$ , $μ^{-} μ^{-} p$ , $τ^{-} τ^{-} p$ , $p μ^{-} τ^{-}$ ) with spin-parity $J^{P} = 1/ 2^{+}$ and $3/ 2^{+}$ , and four-body systems ( $pp μ^{-} μ^{-}$ , $pp τ^{-} τ^{-}$ ) with $J^{P} = 0^{+}$ , $1^{+}$ , and $2^{+}$ . We use complex scaling and Gaussian expansion methods to solve the complex-scaled Schrödinger equation and obtain possible bound and quasi-bound states. The resulting binding energies range from $- 33.8$ ~keV to $- 340$ ~eV. Notably, we present the first theoretical estimation of the bound-state energy levels of $pp μ^{-} μ^{-}$ and $pp τ^{-} τ^{-}$ , which is of significant importance for understanding exotic few-body Coulomb systems. We further analyze spin configurations and root-mean-square radii to elucidate the spatial structure of these bound and quasi-bound states. Our results reveal that $K$ -type spatial configurations play a crucial role in accurately describing bound and quasi-bound states in the hydrogen-molecule-like systems $pp μ^{-} μ^{-}$ and $pp τ^{-} τ^{-}$ . Incorporating $K$ -type configurations significantly alters the mass spectra of these states. Future muon colliders and muon facilities may offer promising platforms for the possible copious production of such heavy flavored hydrogen molecules and molecular ions. For instance, scattering processes such as $2 μ^{-} + H_{2} \to H_{2 μ} + 2 e^{-}$ , $μ^{-} + H_{2} \to H_{μ e} + e^{-}$ , and $μ^{-} + H_{2}^{+} \to H_{2 μ}^{+} + e^{-}$ could be utilized, facilitating detailed studies of intriguing states such as $H_{2 μ}$ , $H_{μ e}$ , and $H_{2 μ}^{+}$ .
Comments:
13 pages, 9 figures, 6 tables, suggestions and comments welcome
Subjects:
Atomic Physics (physics.atom-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2507.21498 [pdf]
PRA(2025)·2 citations
11
[Submitted on 31 Jul 2025] (cross-list from hep-ph)
Local spin polarization by color-field correlators and momentum anisotropy
Haesom Sung🇹🇼 · Berndt Müller🇺🇸 · Di-Lun Yang🇹🇼
We study the local spin polarization of quarks induced by color-field correlators stemming from the correlation of chromo-Lorentz force and chromo-magnetic polarization or chromo-spin Hall effect in the presence of momentum anisotropy. Such effects can trigger longitudinal polarization from fluctuating color fields in glasma or quark gluon plasma phases with transverse expansion for relativistic heavy ion collisions. Especially, from the glasma effect, the resulting longitudinal polarization spectrum of $Λ/ Λ ˉ$ hyperons has a sinusoidal structure with twice the azimuthal angle relative to the anisotropic direction. An order-of-magnitude estimate of the effect aligns with experimental observations. Our findings highlight the significant role of coherent gluon fields as a novel source for spin polarization phenomena in high-energy nuclear collisions.
Comments:
8 pages, 4 figures, final version with improvements over the one in JSPC
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2507.23210 [pdf]
J.Subatomic Part.Cosmol.(2026)·1 citation
12
[Submitted on 31 Jul 2025] (cross-list from hep-ph)
Electric, thermal and thermoelectric response of a hot pion gas in a time dependent background magnetic field
Ankit Kumar🇮🇳 · Gowthama K K🇮🇳 · Vinod Chandra🇮🇳 · Sadhana Dash🇮🇳
The prime focus of the work is to determine the electric, thermal and thermoelectric transport coefficients of a hot pion gas in the presence of time-dependent background magnetic fields. The thermoelectric effect is analyzed by examining the magneto-Seebeck and Nernst coefficients in the hot pionic medium under such conditions. Furthermore, the phenomenologically relevant elliptic flow coefficient, linked to the Knudsen number, is examined. The analysis reveals the significant impact of both the strength and time dependence of the magnetic field on the transport coefficients of the pionic medium. The results are analyzed in contrast to those obtained under a constant magnetic field.
Comments:
11 pages, 7 figures, two-column
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2507.23283 [pdf]
PRD(2025)·3 citations
13
[Submitted on 31 Jul 2025] (cross-list from hep-ph)
Poincaré covariant quantum molecular dynamics: a covariant description of a system of interacting wave packets
Yasushi Nara🇯🇵 · Asanosuke Jinno🇯🇵 · Koichi Murase🇯🇵
We present a new formulation for the mean-field propagation part of the relativistic quantum molecular dynamics, simulating an $N$ -body system of interacting Gaussian wave packets via Lorentz scalar and vector potentials. Covariant equations of motion are derived based on the principle of least action. These covariant equations of motion can be solved with a computational cost comparable to that of conventional noncovariant quantum molecular dynamics. Furthermore, the new equations of motion accurately estimate the density-dependent potential, as demonstrated through comparison of the forces with the numerical integration. We apply them to $N$ -body systems interacting via the Skyrme-type potentials or the relativistic mean field to simulate heavy-ion collisions. Our results show that the derived equations of motion provide a robust approximation to the dynamics of the full numerical integrations.
Comments:
23 pages, 9 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2507.23294 [pdf]
2 citations
14
[Submitted on 31 Jul 2025] (cross-list from hep-ph)
Scale-anomaly-induced binding pressure in hadrons
Daisuke Fujii🇯🇵 · Mitsuru Tanaka🇯🇵
The effect of the QCD scale anomaly on the internal pressure distribution of hadrons is studied based on the trace-traceless decomposition of the energy-momentum tensor. Using recent model-independent results of gravitational form factors as input, the pressure distributions of both pions and nucleons are analyzed in the instant form and the light-front form. It is found that, in all cases, the scale anomaly dominantly generates the negative binding pressure. This result suggests that the phenomenon is a universal feature, independent of models, types of hadrons, and the choice of form.
Comments:
7 pages, 2 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2507.23786 [pdf]
PLB(2025)·10 citations

Affiliations

first authorsco-authorsvia INSPIRE

Heavy flavored hydrogen molecule systems

Local spin polarization by color-field correlators and momentum anisotropy

Electric, thermal and thermoelectric response of a hot pion gas in a time dependent background magnetic field

Poincaré covariant quantum molecular dynamics: a covariant description of a system of interacting wave packets

Scale-anomaly-induced binding pressure in hadrons

Affiliations