Nuclear Theory·nucl-th

Friday·February 3, 2023

10 papers—5 primary·5 cross-listed

01
[Submitted on 1 Feb 2023]
Viewpoint: Vector meson spin alignment by the strong force field
Xin-Nian Wang🇺🇸
Observation of unexpectedly large global spin alignment of $ϕ$ vector mesons in non-central heavy-ion collisions by STAR experiment may reveal the non-perturbative nature of quark interaction in hot matter through fluctuating strong force field with short correlation length.
Comments:
3 pages in LaTeX written for Nuclear Science and Techniques, 2023 24:15, https://doi.org/10.1007/s41365-023-01166-7
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2302.00701 [pdf]
Nucl.Sci.Tech.(2023)·29 citations
02
[Submitted on 2 Feb 2023]
Chiral restoration of nucleons in neutron star matter: studies based on a parity doublet model
Takuya Minamikawa🇯🇵 · Bikai Gao🇯🇵 · Toru kojo🇯🇵 · Masayasu Harada🇯🇵
We review the chiral variant and invariant components of nucleon masses and its consequence on the chiral restoration in extreme conditions, neutron star matter in particular. We consider a model of linear realization of chiral symmetry with the nucleon parity doublet structure that permits the chiral invariant mass, $m_{0}$ , for positive and negative parity nucleons. Nuclear matter is constructed with the parity doublet nucleon model coupled to scalar fields $σ$ , vector fields $(ω, ρ)$ , and to mesons with strangeness through the U(1) $_{A}$ anomaly. In models with large $m_{0}$ , the nucleon mass is insensitive to the medium, and the nuclear saturation properties can be reproduced without demanding strong couplings of nucleons to scalar fields $σ$ and vector fields $ω$ . We confront the resulting nuclear equations of state with nuclear constraints and neutron star observations, and delineate the chiral invariant mass and effective interactions. To further examine nuclear equations of state beyond the saturation density, we supplement quark models to set the boundary conditions from the high density side. The quark models are constrained by the two-solar mass conditions, and such constraints are transferred to nuclear models through the causality and thermodynamic stability conditions. We also calculate various condensates and matter composition from nuclear to quark matter in a unified matter, by constructing a generating functional that interpolates nuclear and quark matter with external fields. Two types of chiral restoration are discussed; the one due to the positive scalar charges of nucleons, and the other triggered by the evolution of the Dirac sea. We found the U(1) $_{A}$ anomaly softens equations of state from low to high density.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2302.00825 [pdf]
Symmetry(2023)·37 citations
03
[Submitted on 2 Feb 2023]
Nuclear response to dark matter signals in Ge and Xe odd-mass targets
M. M. Saez🇯🇵 · O. Civitarese🇦🇷 · T. Tarutina🇦🇷 · K. Fushimi🇦🇷
Abstract: The interaction of dark matter particles (WIMPs) with the odd-mass $^{73}$ Ge and $^{131}$ Xe target nuclei ,{ {that is the recoil rates corresponding to the elastic scattering of WIMPs by these nuclei}}, is analysed in the context of the minimal extensions of the SUSY model. The BCS+QRPA technique plus the quasiparticle-phonon coupling scheme is used to describe the nuclear structure part of the calculations. The resulting values for the nuclear spin content of both nuclei are compared to values previously reported in the literature.
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2302.00879 [pdf]
IJMPE(2023)·1 citation
04
[Submitted on 2 Feb 2023]
Implementation of chiral two-nucleon forces to nuclear many-body methods with Gaussian-wave packets
Tokuro Fukui
Many-body methods that use Gaussian-wave packets to describe nucleon-spatial distribution have been widely employed for depicting various phenomena in nuclear systems, in particular clustering. So far, however, the chiral effective field theory, a state-of-the-art theory of nuclear force, has not been applied to such methods. In this paper, we give the formalism to calculate the two-body matrix elements of the chiral two-nucleon forces using the Gaussian-wave packets. We also visualize the matrix elements and investigate the contributions of the central and tensor forces. This work is a foothold towards an \textit{ab initio} description of various cluster phenomena in view of nucleons, pions, and many-nucleon forces.
Comments:
39 pages, 5 figures, 1 table
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2302.01042 [pdf]
PTEP(2023)·1 citation
05
[Submitted on 2 Feb 2023]
Thermal and atomic effects on coupled-channels heavy-ion fusion
Iain Lee🇬🇧 · Gilbert Gosselin🇫🇷 · Alexis Diaz-Torres🇬🇧
Stellar nuclear fusion reactions take place in a hot, dense plasma within stars. To account for the effect of these environments, the theory of open quantum systems is used to conduct pioneering studies of thermal and atomic effects on fusion probability at a broad range of temperatures and densities. Since low-lying excited states are more likely to be populated at stellar temperatures and increase nuclear plasma interaction rates, a 188Os nucleus was used as a target that interacts with an inert 16O projectile. Key results showed thermal effects yield an average increase in fusion probability of 15.5% and 36.9% for our test nuclei at temperatures of 0.1 and 0.5 MeV respectively, compared to calculations at zero temperature. Thermal effects could be tested in a laboratory using targets prepared in excited states as envisaged in facilities exploiting laser-nucleus interactions.
Comments:
5 pages, 5 figures, Accepted in Physical Review C
Subjects:
Nuclear Theory (nucl-th); Solar and Stellar Astrophysics (astro-ph.SR); Nuclear Experiment (nucl-ex)
arXiv:
2302.01272 [pdf]
PRC(2023)·6 citations
06
[Submitted on 1 Feb 2023] (cross-list from hep-ph)
Deciding on the anomalous magnetic moment of quarks in a framework of nonlocal NJL model
Chowdhury Aminul Islam🇨🇳 · Mahammad Sabir Ali🇮🇳 · Mei Huang🇨🇳
Anomalous magnetic moment (AMM) of quarks in presence of an external magnetic field has been explored using a nonlocal Nambu\textemdash Jona-Lasinio (NJL) model. Various strengths of AMM differing in orders of magnitude are used in the literature. We explore them in our nonlocal framework to decide on their strength. We checked the validity of using constant AMM of quarks and investigate two different temperature and magnetic field dependent forms. The forms are taken as the AMM being proportional to the i) meanfield and the ii) square of the meanfield. On comparison with the lattice data for both the condensate averages and differences, it turns out that the second choice is the most suitable one, in such an effective model scenario. In the process, we also keep track of the phase diagram in the $T - e B$ plane arising from our model calculation. The outcome is reasonable as far as the lattice QCD result is concerned.
Comments:
13 pages, 8 captioned figures, Comments are welcome
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2302.00696 [pdf]
5 citations
07
[Submitted on 1 Feb 2023] (cross-list from hep-ph)
N-particle irreducible actions for stochastic fluids
Jingyi Chao🇨🇳 · Thomas Schaefer🇺🇸
We construct one- and two-particle irreducible (1PI and 2PI) effective actions for the stochastic fluid dynamics of a conserved density undergoing diffusive motion. We compute the 1PI action at one-loop order, and the 2PI action in two-loop approximation. We derive a set of Schwinger-Dyson equations, and regularize the resulting equations using Pauli-Villars fields. We numerically solve the Schwinger-Dyson equations for a non-critical fluid. We find that higher-loop effects summed by the Schwinger-Dyson renormalize the non-linear coupling. We also find indications of a diffuson-cascade, the appearance $n$ -loop corrections with smaller and smaller exponential suppression.
Comments:
15 pages, 7 figures; revised version to appear in JHEP
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2302.00720 [pdf]
JHEP(2023)·5 citations
08
[Submitted on 1 Feb 2023] (cross-list from hep-ph)
Searching for a dark matter particle with anti-protonic atoms
M. Doser🇨🇭 · G. Farrar🇺🇸 · G. Kornakov🇵🇱
A wide range of dark matter candidates have been proposed and are actively being searched for in a large number of experiments, both at high (TeV) and low (sub meV) energies. One dark matter candidate, a deeply bound $uu dd ss$ sexaquark, $S$ , with mass $\sim 2$ GeV (having the same quark content as the hypothesized H-dibaryon, but long lived) is particularly difficult to explore experimentally. In this paper, we propose a scheme in which such a state could be produced at rest through the formation of $p ˉ -^{3}$ He antiprotonic atoms and their annihilation into $S$ + $K^{+} K^{+} π^{-}$ , identified both through the unique tag of a S=+2, Q=+1 final state, as well as through full kinematic reconstruction of the final state recoiling against it.
Comments:
10 pages, 4 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2302.00759 [pdf]
EPJC(2023)·7 citations
09
[Submitted on 2 Feb 2023] (cross-list from hep-ph)
Study of the $D K$ interaction with femtoscopic correlation functions
Zhi-Wei Liu🇨🇳 · Jun-Xu Lu🇨🇳 · Li-Sheng Geng🇨🇳
The $D K$ interaction in isospin zero is known to be attractive to such an extent that a bound state can be generated, which can be associated with the mysterious $D_{s 0}^{*} (2317)$ . In this work, we calculate the $D K$ femtoscopic correlation function in the coupled-channel framework for different source sizes that can directly probe the strongly attractive $D K$ interaction, which is otherwise inaccessible due to the unstable nature of $D$ and $K$ mesons, and therefore can help elucidate the nature of $D_{s 0}^{*} (2317)$ . We further generalize the study of source size dependence to various interactions, ranging from repulsive, weakly attractive, moderately attractive, and strongly attractive, in a square-well model. We hope that our study can motivate future experimental measurements of the $D K$ correlation function and other interactions relevant to the understanding of the nature of the many exotic hadrons discovered so far.
Comments:
8 pages, 3 figures; clarifications added and discussions refined, to appear in Physical Review D
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2302.01046 [pdf]
PRD(2023)·68 citations
10
[Submitted on 2 Feb 2023] (cross-list from hep-ph)
Tomography of pions and protons via transverse momentum dependent distributions
P. C. Barry🇺🇸 · L. Gamberg🇺🇸 · W. Melnitchouk🇺🇸 · E. Moffat🇺🇸 · D. Pitonyak🇺🇸 · A. Prokudin🇺🇸 · N. Sato🇺🇸
We perform the first simultaneous extraction of parton collinear and transverse degrees of freedom from low-energy fixed-target Drell-Yan data in order to compare the transverse momentum dependent (TMD) parton distribution functions (PDFs) of the pion and proton. We demonstrate that the transverse separation of the quark field encoded in TMDs of the pion is more than $4 σ$ smaller than that of the proton. Additionally, we find the transverse separation of the quark field decreases as its longitudinal momentum fraction decreases. In studying the nuclear modification of TMDs, we find clear evidence for a transverse EMC effect. We comment on possible explanations for these intriguing behaviors, which call for a deeper examination of tomography in a variety of strongly interacting quark-gluon systems.
Comments:
7 pages, 3 figures; version to appear in Phys. Rev. D
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
2302.01192 [pdf]
PRD(2023)·49 citations

Affiliations

first authorsco-authorsvia INSPIRE