Nuclear Theory·nucl-th

Monday·January 27, 2025

7 papers—4 primary·3 cross-listed

01
[Submitted on 24 Jan 2025]
Theoretical study of the $Σ N$ cusp in the $K^{-} d \to π Λ N$ reaction
Shunsuke Yasunaga🇯🇵 · Daisuke Jido🇯🇵
The $K^{-} d \to π Λ N$ reaction is useful for exploring the hyperon-nucleon interaction through final state interactions. In particular, the cusp structure of the $Λ N$ invariant mass spectrum at the $Σ N$ threshold contains information about the s-wave interaction of 1/2-isospin hyperon-nucleon systems. The calculation of the spectrum is performed with the aim of extracting the scattering length of the $Σ N (I = 1/2)$ channel that couples to the $Λ N$ channel from this reaction, and the results are discussed in comparison with experimental data to highlight the factors that should be considered.
Comments:
6 pages, 3 figures, 1 table. Contribution to the proceedings of the 10th International Conference on Quarks and Nuclear Physics (QNP2024)
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2501.14227 [pdf]
PoS(2025)·1 citation
02
[Submitted on 24 Jan 2025]
Longitudinal flow decorrelations in light ion collisions
Hadi Mehrabpour🇨🇳 · Abhisek Saha🇨🇳
This study presents a detailed analysis of longitudinal flow decorrelations in light ion collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider(LHC) energies for the first time. We compare different theoretical models of the oxygen structure and find that certain observables, such as the flow vector correlator, can distinguish between them, particularly highlighting differences between the variational Monte Carlo (VMC) structure and other models, such as Nuclear Lattice Effective Field Theory (NLEFT) and the Projected Generator Coordinate Method (PGCM), which behave similarly. We further examine flow decorrelations across different systems, including d+Au and O+O collisions at 200 GeV, as well as Ne+Ne and O+O collisions at 6.37 TeV, indicating a hierarchy in decorrelations that underscores the complexity of these interactions. Our findings emphasize that the role of asymmetry in d+Au collisions and its impact on flow correlations is mitigated using a modified flow correlation defined as a ratio of two flow vector covariances derived from different pairs of pseudorapidity bins. Additionally, our analysis of flow angle decorrelations shows diverse distributions across various systems, finding distinct patterns in d+Au collisions compared to other collision systems.
Comments:
12 pages, 11 figures
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
2501.14243 [pdf]
EPJC(2025)·6 citations
03
[Submitted on 24 Jan 2025]
QED corrections to the parity-violating asymmetry in high-energy electron-nucleus collisions
Xavier Roca-Maza🇪🇸 · D H. Jakubassa-Amundsen🇩🇪
The parity-violating asymmetry, including leading-order QED corrections to the Coulomb potential, is calculated non-perturbatively by solving the Dirac equation. At GeV collision energies and forward scattering angles, QED effects enhance the asymmetry by approximately 5% for the recently measured nuclei 27Al, 48Ca, and 208Pb. The corrections result in a shift of the estimated neutron radius, leading to an increase in the inferred neutron skin thicknesses of these nuclei and, thus, to the pressure neutrons feel around nuclear saturation density.
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2501.14375 [pdf]
PRL(2025)·16 citations
04
[Submitted on 24 Jan 2025]
Level shifts of exotic deuterium atoms from effective range parameters
Pierre-Yves Duerinck🇧🇪 · Rimantas Lazauskas🇫🇷 · Jérémy Dohet-Eraly🇧🇪
We discuss various methods for determining the level shifts induced by short-range interactions in exotic atoms which are formed by a hadron and a nucleus of opposite charge. The energy shifts can be related to the effective range parameters through Deser or Trueman formulas. In order to assess the accuracy and the reliability of this indirect approach, its predictions are compared with direct bound-state calculations. Notably, the importance of including the Coulomb potential in scattering calculations is highlighted. Finally, the impact of multipole terms in the asymptotic electromagnetic interaction is examined. It is demonstrated that an indirect approach remains relevant by accounting for these effects perturbatively.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2501.14407 [pdf]
PRC(2025)·4 citations
05
[Submitted on 24 Jan 2025] (cross-list from hep-ph)
Study on axial fields in the dynamically assisted Schwinger effect
Chengpeng Yu🇯🇵
The dynamically assisted Schwinger effect, the generation of fermion-antifermion pairs in vacuum under a strong, slow-varying field and a weak, high-frequency field, has become a promising avenue to probe the vacuum structure and the nonlinear dynamics of QED. However, the role of axial fields in this phenomenon has remained underexplored. This study aims at analyzing how spatial axial fields influence particle production in the dynamically assisted Schwinger effect. Employing the high-frequency effective theory based on the Floquet-Magnus expansion, we demonstrate that a spatial axial field can occur as the effective field of a circular polarized high-frequency plane wave and significantly increase the number of fermions produced across different timescales. This enhancement offers both theoretical insights and useful tools for the experimental implementation of the Schwinger effect.
Comments:
12 pages, 4 figures, revised based on the journal version of this article
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2501.14283 [pdf]
PRD(2025)·0 citations
06
[Submitted on 24 Jan 2025] (cross-list from hep-ph)
Can one-loop corrections to the one-gluon exchange potential adequately describe the charmed meson spectrum?
A. Capelo-Astudillo🇪🇨 · T. Aguilar🇪🇨 · M. Conde-Correa🇪🇨 · A. Duenas-Vidal🇪🇨 · P. G. Ortega🇪🇸 · J. Segovia🇪🇸
We investigate the charmed meson spectrum using a constituent quark model (CQM) with one-loop corrections applied to the one-gluon exchange (OGE) potential. The study aims to understand if the modified version of our CQM sufficiently account for the charmed meson spectrum observed experimentally, without invoking exotic quark and gluon configurations such as hybrid mesons or tetraquarks. Within this model, charmed mesons' masses are computed, comparing theoretical predictions to experimental data. The results, within uncertainties, suggest that our theoretical framework generally reproduces mass splittings and level ordering observed for charmed mesons. Particularly, large discrepancies between theory and experiment found in $P$ -wave states are, at least, significantly ameliorated by incorporating higher-order interaction terms. Therefore, the findings emphasize that while the traditional quark model is limited in fully describing charmed mesons, enhanced potential terms may bridge the gap with experimental observations. The study contributes a framework for predicting excited charmed meson states for future experimental validation.
Comments:
9 pages, 2 Tables, 1 Figure
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2501.14386 [pdf]
Symmetry(2025)·2 citations
07
[Submitted on 24 Jan 2025] (cross-list from hep-ph)
Automated NLO calculations for asymmetric hadron-hadron collisions in MadGraph5_aMC@NLO
Carlo Flore🇮🇹 · Daniel Kikoła🇵🇱 · Aleksander Kusina🇵🇱 · Jean-Philippe Lansberg🇫🇷 · Olivier Mattelaer🇧🇪 · Anton Safronov🇵🇱
We have extended {\tt MadGraph5\_aMC@NLO} capabilities by implementing computations for asymmetric hadron-hadron collisions, including proton-nucleus, pion-hadron or nucleus-nucleus collisions in order to obtain a tool for automated perturbative computations of cross sections (or ratios of cross sections) in asymmetric reactions at next-to-leading (NLO) order in $α_{S}$ in collinear factorisation. This tool, like the original symmetric version of \texttt{MadGraph5\_aMC@NLO}, automatically computes cross sections for different factorisation and renormalisation scales and PDFs provided by the {\tt LHAPDF} library, thereby allowing for an easy assessment of the associated theoretical uncertainties. In this paper, we present the validation of our code using $W$ and $Z$ boson production in $p$ Pb collisions and Drell-Yan-pair production in $π W$ collisions. We also illustrate the capabilities of the framework by providing cross section and nuclear modification factors with their uncertainties for the production of $W$ and $Z$ bosons, charm and bottom quarks as well as associated production of $b b ˉ + H^{0}$ in $p$ Pb collisions at the LHC.
Comments:
17 pages, 6 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2501.14487 [pdf]
EPJA(2025)·4 citations

Affiliations

first authorsco-authorsvia INSPIRE

Theoretical study of the ΣN cusp in the K−d→πΛN reaction

Longitudinal flow decorrelations in light ion collisions

QED corrections to the parity-violating asymmetry in high-energy electron-nucleus collisions

Level shifts of exotic deuterium atoms from effective range parameters

Study on axial fields in the dynamically assisted Schwinger effect

Can one-loop corrections to the one-gluon exchange potential adequately describe the charmed meson spectrum?

Automated NLO calculations for asymmetric hadron-hadron collisions in MadGraph5_aMC@NLO

Affiliations

Theoretical study of the $Σ N$ cusp in the $K^{-} d \to π Λ N$ reaction