Nuclear Theory·nucl-th

Tuesday·July 29, 2025

13 papers—7 primary·6 cross-listed

08
[Submitted on 27 Jul 2025] (cross-list from hep-ph)
Meson-Exchange Currents in Quasielastic Charged-Current Neutrino Reactions with Single-Nucleon Knockout
P.R. Casale🇪🇸 · J.E. Amaro🇪🇸 · V. Belocchi🇮🇹 · M.B. Barbaro🇮🇹 · Marco Martini🇫🇷
The effect of meson-exchange currents on charged-current quasielastic neutrino scattering with single-nucleon emission is computed and analyzed within the relativistic Fermi gas model. This contribution arises primarily from the interference between one-body and two-body currents, where the two-body operator excites a 1p1h state in the presence of a second, spectator nucleon. The results obtained show a reduction of the vector, axial and vector-axial transverse response functions and, consequently, a decrease in the total neutrino cross section. In addition to a comparison with the non-relativistic limit, other models are also explored, such as the relativistic mean field model for nuclear matter and the superscaling analysis with relativistic effective mass, both of which yield qualitatively similar results.
Comments:
25 pages, 19 figures. Revised version with new figures 17, 18, and 19
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2507.20246 [pdf]
PRC(2025)·5 citations
09
[Submitted on 27 Jul 2025] (cross-list from hep-ph)
Analytic structure of stress-energy response functions and new Kubo formulae
Sangyong Jeon🇨🇦 · Alina Czajka🇵🇱 · Juhee Hong🇰🇷
Determining the transport properties of Quark-Gluon Plasma is one of the most important aspects of relativistic heavy ion collision studies. Field-theoretical calculations of the transport coefficients such as the shear and bulk viscosities require Kubo formulae which in turn require real-time correlation functions of stress-energy tensors. Consequently, knowing the analytic structure of these correlation functions is essential in any such studies. Using the energy-conservation laws and the results from the gravity-hydrodynamics analysis, we determine the low-frequency and low-wavenumber analytic structures of all stress-energy correlation functions in the rest frame of the medium. By comparing with the diffusion and sound spectra from the second-order and the third-order relativistic hydrodynamics, various new Kubo formulae are derived in the limit where the zero-frequency limit is taken first. We also show that the meaning of the Kubo formulae for relaxation times can change when higher-order terms are added to hydrodynamics. A subtle issue of taking the zero frequency and zero wavenumber limits when using skeleton diagrams is addressed as well.
Comments:
14 pages, no figures. Published version with two typographical corrections. Equations (B4) and (B5) had - instead of +
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2507.20302 [pdf]
PRC(2025)·5 citations
10
[Submitted on 27 Jul 2025] (cross-list from cond-mat.quant-gas)
Low-energy atomic scattering: s-wave relation between the interaction potential and the phase shift
Francesco Lorenzi🇮🇹 · Luca Salasnich🇮🇹
We investigate the on-shell approximation in the context of s-wave scattering for ultracold two-body collisions. Our analysis systematically covers spatial dimensions D=1,2,3 , with the aim of identifying the regimes in which the approximation remains valid when applied to commonly used model interaction potentials. Specifically, we focus on the square well and delta shell potentials, both of which admit analytical solutions for the s-wave scattering problem in all dimensions considered. By employing the exact analytical expressions for the s-wave scattering phase shift, we perform a direct comparison between the exact on-shell matrix element of the interaction potential and their corresponding approximations across a range of collision momenta. Particular attention is given to the low-energy regime. Our findings indicate that, although the on-shell approximation generally improves with increasing momentum, its accuracy also improves for weaker potentials. Remarkably, in the limit of weak interactions, we demonstrate that the on-shell approximation becomes exact at leading order. In this regime, the approximation offers a controlled means of deriving the low-momentum expansion of the potential and may serve as a useful tool in constructing effective interactions for quantum field theories.
Comments:
11 pages, 4 figures. To appear in Annalen der Physik
Subjects:
Quantum Gases (cond-mat.quant-gas); Nuclear Theory (nucl-th)
arXiv:
2507.20421 [pdf]
Annalen Phys.(2025)·0 citations
11
[Submitted on 28 Jul 2025] (cross-list from hep-ex)
Understanding neutrino pion production with the GiBUU model
Qiyu Yan🇨🇳 · Kaile Wen🇨🇳 · Kai Gallmeister🇩🇪 · Xianguo Lu🇬🇧 · Ulrich Mosel🇩🇪 · Yangheng Zheng🇨🇳
Pion production is a major source of systematic uncertainty in neutrino oscillation measurements. We report a systematic investigation of neutrino-induced pion production using MINERvA and MicroBooNE data within the GiBUU theoretical framework. The analysis begins by establishing baseline model parameters using inclusive and pionless data from MINERvA, MicroBooNE, and T2K experiments. We then examine the role of in-medium effects, including resonance broadening and nucleon-nucleon final-state interactions. While agreement with individual datasets can be achieved through specific model configurations, we demonstrate the difficulty of a unified description across all experiments: MINERvA measurements prefer minimum in-medium modifications, whereas MicroBooNE data require the maximum in-medium enhancement, revealing the complexity and richness of the underlying nuclear dynamics.
Comments:
15 pages, 26 figures, accepted version by PRD
Subjects:
High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2507.20539 [pdf]
PRD(2025)·7 citations
12
[Submitted on 28 Jul 2025] (cross-list from hep-lat)
Lattice study of scattering phase shifts for $D D^{*}$ and $B B^{*}$ systems using twisted boundary conditions: Search for bound state formation
Masato Nagatsuka🇯🇵 · Shoichi Sasaki🇯🇵
We investigate the $S$ - and $P$ -wave phase shifts for the $D D^{*}$ and $B B^{*}$ scatterings using Lüscher's finite-size method under twisted boundary conditions to search for doubly charmed tetraquaks, $T_{cc}^{+}$ , and doubly bottomed tetraquarks, $T_{bb}^{-}$ as the hadronic bound states. The $T_{cc}^{+}$ state was observed as a peak just bellow the $D D^{*}$ threshold by LHCb Collaboration, while the $T_{bb}^{-}$ state is a theoretically predicted tetraquark state having heavier quark flavors $bb u ˉ d ˉ$ . Lüscher's finite-size method is one of the well established methods for calculating the scattering phase shifts between two hadrons in lattice QCD simulations. Several studies have used simulations under the periodic boundary condition to determine the scattering phase shifts at a few discrete momenta for the $D D^{*}$ system. However, the scattering phase shift has not been investigated for the $B B^{*}$ system. In this study, $S$ - and $P$ -wave scattering phase shifts for the $D D^{*}$ and $B B^{*}$ systems in both $I = 0$ and $I = 1$ channels under several types of partially twisted boundary conditions. The use of the partially twisted boundary conditions enables us to obtain the scattering phase shift at any momentum by continuously varying the twisting angle. It also allows us to easily access the $P$ -wave scattering phase shifts through the mixing of $S$ - and $P$ -waves, which is induced by the imposed boundary conditions. The 2+1 flavor PACS-CS gauge ensembles at $m_{π} = 295$ , 411 and 569 MeV are used. For charm and bottom quarks, the relativistic heavy quark action is adopted to reduce the lattice discretization artifacts due to the heavy quark mass. We discuss the emergence of a shallow bound state with a binding energy of $O (100)$ keV at the physical pion mass in the $B B^{*}$ system, which has the quantum number $I (J^{P}) = 0 (1^{+})$ .
Comments:
39 pages, 10 figures; v2: version published in PRD
Subjects:
High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2507.20712 [pdf]
PRD(2025)·5 citations
13
[Submitted on 28 Jul 2025] (cross-list from astro-ph.HE)
Rotating Proto-Neutron Stars Admixed with Mirror Dark Matter: A two fluid approach
Adamu Issifu🇪🇸 · Andreas Konstantinou🇨🇾 · Prashant Thakur🇮🇳 · Tobias Frederico🇪🇸
This work investigates the impact of mirror dark matter (DM) on the global properties of rotating neutron stars (NSs) across evolutionary stages, from hot, lepton-rich protoneutron stars (PNSs) to cold, catalyzed NSs along the Kelvin-Helmholtz timescale. The baryonic matter (BM) is modeled using a relativistic mean-field (RMF) approach with density-dependent couplings, while the dark sector mirrors the visible sector with analogous thermodynamic conditions. Using a two-fluid formalism with purely gravitational DM-BM interaction, we find that rotation enlarges the star, whereas DM admixture increases compactness and enhances gravitational stability. However, increased compactness due to DM lowers the threshold for rotational instabilities, making DM-admixed stars more susceptible. Rotation decreases {central temperature behavior} by redistributing thermal energy over a larger volume and reducing central density, while DM raises temperatures by deepening the gravitational potential and increasing thermal energy. Stars become more prone to collapse and rotational instabilities as frequency ( $ν$ ) rises and the polar-to-equatorial radius ratio ( $r_{p} / r_{e}$ ) decreases, especially near the Keplerian limit ( $ν_{K}$ ). DM-admixed stars also show higher surface gravitational redshifts due to their compactness. Our results qualitatively agree with universal relations primarily derived for rotating cold stars. These findings highlight competing effects of rotation and DM on NS thermal evolution, structure, and observables, potentially offering indirect probes of DM within NSs.
Comments:
13 pages, 6 figures and 3 tables (Accepted for publication in Physical Review D.)
Subjects:
High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2507.20823 [pdf]
PRD(2025)·11 citations

Affiliations

first authorsco-authorsvia INSPIRE

Meson-Exchange Currents in Quasielastic Charged-Current Neutrino Reactions with Single-Nucleon Knockout

Analytic structure of stress-energy response functions and new Kubo formulae

Low-energy atomic scattering: s-wave relation between the interaction potential and the phase shift

Understanding neutrino pion production with the GiBUU model

Lattice study of scattering phase shifts for DD∗ and BB∗ systems using twisted boundary conditions: Search for bound state formation

Rotating Proto-Neutron Stars Admixed with Mirror Dark Matter: A two fluid approach

Affiliations

Lattice study of scattering phase shifts for $D D^{}$ and $B B^{}$ systems using twisted boundary conditions: Search for bound state formation