Nuclear Theory·nucl-th

Monday·February 17, 2025

12 papers—3 primary·9 cross-listed

01
[Submitted on 14 Feb 2025]
Improvement to Generalized Separable Expansion Method in Lippmann-Schwinger Equation
Hiroyuki Kamada
Realistic nucleon-nucleon (NN) potentials are generally not in separable form, but there is a way to convert them into separable potentials, called the generalized separable expansion (GSE). When the separable potential is substituted into a three-body Faddeev equation, which generally has two Jacobi momenta, the integral equation is conveniently reduced to a one-variable integral equation. The two-body scattering t-matrix of the conventional GSE does not have an exact singularity at the energy threshold of the two-body bound state. The newly introduced GSE improves this by treating the singularity analytically.
Comments:
8pages, no figure
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2502.09911 [pdf]
PTEP(2025)·8 citations
02
[Submitted on 14 Feb 2025]
Chiral symmetry and peripheral neutron- $α$ scattering
Yilong Yang · Evgeny Epelbaum · Jie Meng · Lu Meng · Pengwei Zhao
We propose and demonstrate that peripheral neutron- $α$ scattering at low energies can serve as a sensitive and clean probe of the long-range three-nucleon forces. To this aim, we perform {\it ab initio} quantum Monte Carlo calculations using two- and three-nucleon interactions derived in chiral effective field theory up to third expansion order. We show that the longest-range three-nucleon force stemming from the two-pion exchange plays a crucial role in the proper description of the neutron- $α$ $D$ -wave phase shifts. Our Letter reveals the predictive power of chiral symmetry in the few-body sector and opens a new direction for probing and constraining three-nucleon forces.
Comments:
6 pages, 4 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2502.09961 [pdf]
PRL(2025)·18 citations
03
[Submitted on 14 Feb 2025]
Modeling of acceleration in heavy-ion collisions: occurrence of temperature below the Unruh temperature
G. Yu. Prokhorov🇷🇺 · D. A. Shohonov🇷🇺 · O. V. Teryaev🇷🇺 · N. S. Tsegelnik🇷🇺 · V. I. Zakharov🇷🇺
It has recently been shown that extremely strong electric fields can be created in central collisions of heavy ions, due to which the Schwinger effect can be significant. A direct analogue of the electric field in hydrodynamics is the acceleration of the medium. Using the parton-hadron-string dynamics (PHSD) framework we model the Au-Au collisions at intermediate collision energies $s_{N N} = 4.5 - 11.5$ GeV and obtain the spatial distribution of acceleration at different time moments. The present study demonstrates that extremely high acceleration of the order of 1 GeV may be generated in both central and non-central collisions, and that the distribution exhibits a core-corona structure. Consequently, in contrast to the case with an electric field, the Unruh effect is expected to be significant. It is demonstrated that for the confined phase the temperature is less than the Unruh temperature. Conversely, in the deconfined phase, the relationship is inverse. The obtained results thus support the prediction about the existence of states with $T < T_{U}$ at the early stages of the collision and the associated complementary description of thermalization in terms of the novel phase transition at the Unruh temperature.
Comments:
15 pages, 7 figures, To appear in Physical Review C
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th)
arXiv:
2502.10146 [pdf]
PRC(2025)·16 citations
04
[Submitted on 13 Feb 2025] (cross-list from hep-ph)
Effective theories for nuclei at high energies
Oscar Garcia-Montero🇩🇪 · Sören Schlichting🇩🇪
We discuss the application of the Color Glass Condensate (CGC), an effective field theory of Quantum Chromodynamics (QCD), to describe high-energy nuclear interactions. We first provide an introduction to the methods and language of the CGC, its role in understanding gluon saturation in heavy-ion collisions at the LHC and RHIC, and its relevance in various scattering processes such as Deep Inelastic Scattering (DIS). The application of the CGC effective field theory to describe hadron-hadron collisions is discussed in the scope of asymmetric \textit{dilute-dense} collisions, and Heavy-Ion Collisions in the \textit{dense-dense} limit. The review covers theoretical foundations, recent advancements, and phenomenological applications, focusing on using the CGC to determine the initial conditions of heavy-ion collisions.
Comments:
40 pages, 8 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2502.09721 [pdf]
EPJA(2025)·19 citations
05
[Submitted on 13 Feb 2025] (cross-list from hep-th)
Dirac fermions under imaginary rotation
Tudor Pătuleanu🇷🇴 · Amalia Dariana Fodor🇷🇴 · Victor E. Ambrus🇷🇴 · Cosmin Crucean🇷🇴
In the present study, we investigate the properties of an ensemble of free Dirac fermions, at finite inverse temperature $β$ and finite chemical potential $μ$ , undergoing rigid rotation with an imaginary angular velocity $Ω = i Ω_{I}$ . Our purpose is to establish the analytical structure of such states, as well as the prospects (and dangers) of extrapolating results obtained under imaginary rotation to the case of real rotation. We show that in the thermodynamic limit, the state of the system is akin to a stationary system with modified inverse temperature $β_{q} = q β$ and the same chemical potential, where $q$ is the denominator of the irreducible fraction $ν = β Ω_{I} /2 π = p / q$ . The temperature of the system becomes a fractal function of the rotation parameter, as in the case of the scalar field. The chemical potential breaks the fractalization of fermions. We also compute the thermodynamic potential $Φ$ and associated thermodynamic functions, showing that they also exhibit fractal behavior. Finally, we evaluate the axial and helical fluxes through the transverse plane, generated through the vortical effects, and show that they diverge in the thermodynamic limit, in the case when $ν = 1/ q$ and $q \to \infty$ .
Comments:
31 pages, 6 figures and many cool results
Subjects:
High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2502.09738 [pdf]
PRD(2025)·6 citations
06
[Submitted on 13 Feb 2025] (cross-list from nucl-ex)
Experimental Search for the Chiral Magnetic Effect in Relativistic Heavy-Ion Collisions: A Perspective
Yicheng Feng🇺🇸 · Sergei A. Voloshin🇺🇸 · Fuqiang Wang🇺🇸
The chiral magnetic effect (CME) refers to generation of the electric current along a magnetic field in a chirally imbalanced system of quarks. The latter is predicted by quantum chromodynamics to arise from quark interaction with non-trivial topological fluctuations of the vacuum gluonic field. The CME has been actively searched for in relativistic heavy-ion collisions, where such gluonic field fluctuations and a strong magnetic field are believed to be present. The CME-sensitive observables are unfortunately subject to a possibly large non-CME background, and firm conclusions on a CME observation have not yet been reached. In this perspective, we review the experimental status and progress in the CME search, from the initial measurements more than a decade ago, to the dedicated program of isobar collisions in 2018 and the release of the isobar blind analysis result in 2022, to intriguing hints of a possible CME signal in Au+Au collisions, and discuss future prospects of a potential CME discovery in the anticipated high-statistic Au+Au collision data at the Relativistic Heavy-Ion Collider by 2025. We hope such a perspective will help sharpening our focus on the fundamental physics of the CME and steer its experimental search.
Comments:
22 pages, 21 figures, as published
Subjects:
Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2502.09742 [pdf]
PRResearch(2025)·18 citations
07
[Submitted on 13 Feb 2025] (cross-list from hep-ph)
Tomography of Pions and Kaons in the QCD Vacuum: Transverse Momentum Dependent Parton Distribution Functions
Wei-Yang Liu🇺🇸 · Ismail Zahed🇺🇸
We evaluate the pion and kaon transverse momentum dependent parton distribution functions (TMDPDFs) in the instanton liquid model (ILM), a model of the QCD vacuum at low resolution. The relevant TMDs are factored into a constituent quark distribution times a rapidity dependent soft factor from staple-shaped Wilson lines, for fixed parton longitudinal momentum and transverse separation. The results are evolved to higher rapidities using the Collins-Soper (CS) kernel and higher resolution using renormalization group evolution. The comparison to existing extractions of pion TMDs from Drell-Yan (DY) data is briefly discussed.
Comments:
23 pages, 13 figures, typo fixed and plots corrected
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
2502.09789 [pdf]
PRD(2025)·4 citations
08
[Submitted on 14 Feb 2025] (cross-list from hep-ph)
Sensitivity study of a sapphire detector using Coherent Elastic Neutrino-Nucleus Scattering process
S. P. Behera🇮🇳
The Indian Coherent Neutrino-nucleus Scattering Experiment(ICNSE) has been proposed at Bhabha Atomic Research Centre in India to measure the coherent elastic neutrino-nucleus scattering process using electron antineutrinos produced from reactors. Phenomenological studies are performed to find out the sensitivity of a sapphire detector for various fundamental physics parameters at an exposure of one year. Reactors of different core compositions, sizes, and thermal powers have been considered as sources of electron antineutrinos. The potential of the ICNSE to measure the weak mixing angle at a low energy regime has been extracted. Furthermore, the detector's capability has been investigated for examining the electromagnetic properties of neutrinos, including their magnetic moment. Additionally, an exploration has been conducted on the detector's sensitivity in restricting new interactions between neutrinos and electrons or nuclei, thereby constraining the parameter space related to light mediators. It is found that the ICNSE detector can put a stronger constraints on the scalar and vector mediators masses.
Comments:
11 pages, 7 figures, Published version
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2502.09972 [pdf]
PRD(2025)·5 citations
09
[Submitted on 14 Feb 2025] (cross-list from hep-ph)
Nuclear modification of $B_{c}$ mesons in relativistic heavy-ion collisions based on a linear Boltzmann transport model
Lejing Zhang🇨🇳 · Xiaowen Li🇨🇳 · Wen-Jing Xing🇨🇳 · Shanshan Cao🇨🇳 · Guang-You Qin🇨🇳
The nuclear modification factor ( $R_{AA}$ ) of $B_{c}$ mesons in high-energy nuclear collisions provides a novel probe of heavy quark interactions with the quark-gluon plasma (QGP). Based on a linear Boltzmann transport model that incorporates both Yukawa and string types of interactions between heavy quarks and the QGP, we study the production and evolution of heavy quarks and $B_{c}$ mesons within the same framework. A $B_{c}$ bound state dissociates while one of its constituent heavy quarks scatters with the QGP with momentum transfer greater than its binding energy. The medium-modified charm and bottom quarks can recombine into $B_{c}$ mesons, and the medium-modified bottom quarks can also fragment to $B_{c}$ mesons. We find that most primordial $B_{c}$ mesons generated from the initial hard collisions dissociate inside the QGP. The production of $B_{c}$ mesons is primarily driven by the recombination mechanism at low transverse momentum and fragmentation at high transverse momentum. The string interaction dominates over the Yukawa interaction in the nuclear modification of $B_{c}$ mesons. The participant number dependence of the $B_{c}$ meson $R_{AA}$ is determined by the complicated interplay between the heavy quark yield, energy loss, and the QGP volume. We obtain a reasonable description of the $R_{AA}$ of $B_{c}$ mesons in Pb+Pb collisions at $s_{NN} = 5.02$ TeV, and provide predictions for Au+Au collisions at $s_{NN} = 200$ GeV.
Comments:
11 pages, 9 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
2502.10107 [pdf]
PRC(2025)·2 citations
10
[Submitted on 14 Feb 2025] (cross-list from hep-ph)
Chiral symmetry restoration in QC_2D from effective model using the functional renormalization group
G. Fejos🇯🇵 · D. Suenaga🇯🇵
The order of the chiral phase transition in two-color and two-flavor QC $_{2}$ D is investigated using the functional renormalization group (FRG) technique in an effective model setting. We calculate the $β$ function of all couplings in the dimensionally reduced Ginzburg-Landau free energy functional with Pauli-Gürsey SU(4) symmetry. We compare results of the perturbative $ϵ$ expansion approach with those obtained via the FRG, evaluated directly in $d = 3$ dimensions. The perturbative results suggest that the fixed-point structure is more intricate than that of three-color QCD, a conclusion further supported by the FRG analysis. Both methods display an infrared stable $O (6)$ fixed point at infinite axial anomaly; however, the FRG approach also reveals the existence of $U_{A} (1)$ anomaly-free fixed points, which can become infrared stable if the anomaly in the underlying theory vanishes at the critical temperature. These findings imply that the phase transition can be of second order, consistent with earlier findings for three colors.
Comments:
7 pages, 1 figure, matches 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:
2502.10134 [pdf]
PRD(2025)·5 citations
11
[Submitted on 14 Feb 2025] (cross-list from hep-ph)
Pion condensation versus 2SC, speed of sound, and charge neutrality effects in the quark-meson diquark model
Jens O. Andersen🇳🇴 · Mathias P. Nødtvedt🇳🇴
We employ the two-flavor quark-meson diquark model as a low-energy model for QCD at non-zero quark and isospin chemical potentials $μ$ and $μ_{I}$ , and at zero temperature. We map out the phase diagram in the $μ$ - $μ_{I}$ plane, which has four phases: a vacuum phase, a phase with condensed charged pions/Cooper pairs of $u$ and $d ˉ$ quarks, a normal quark matter phase, and a color superconducting phase (2SC phase). %In the 2SC phase, we study the effects of imposing color and %electric charge neutrality. The global symmetry breaking $S U (3)_{c} \to S U (2)_{c}$ in the 2SC phase gives rise to a number of Nambu-Goldstone bosons. We classify them and briefly discuss their properties. We calculate the speed of sound $c_{s}$ in the two special cases, finite $μ_{I}$ and $μ = 0$ , and finite $μ$ and $μ_{I} = 0$ . In both cases, the speed of sound exhibits a maximum and approaches the conformal limit from above as the density increases. For non-zero isospin $μ_{I}$ , this behavior is in agreement with the speed of sound obtained from lattice simulations. In the 2SC phase, the behavior is qualitatively the same if we impose local charge neutrality. Finally, we discuss the possibility of having a mixed phase of negatively charged normal quark matter and positively charged 2SC matter with global color charge neutrality imposed on the latter.
Comments:
12 pages, 7 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
2502.10229 [pdf]
PRD(2026)·15 citations
12
[Submitted on 14 Feb 2025] (cross-list from gr-qc)
Spacetime curvature corrections for the Yukawa potential and its application for the Reissner-Nordström Metric
J. V. Zamperlini🇧🇷 · C. C. Barros Jr🇧🇷
In this paper, we investigate the influence of the spacetime curvature on the Yukawa potential, focusing on boson-boson interactions derived from the {\Phi^3} theory. Using the Bunch-Parker propagator expansion within Born's first approximation, we derive a Yukawa-like potential in a curved spacetime. We analyze the impact of the curvature on the propagator in momentum space, revealing modifications to the potential and showing that the corrections are determined by geometric quantities from Einstein's equations, like the Ricci scalar and tensor. We illustrate this using the Reissner-Nordström metric, highlighting the corrections' magnitude for specific parameters. Our results underscore the nuanced interplay between spacetime curvature and quantum interactions, providing insights into nucleon-nucleon systems in curved spacetimes or near strong gravitational fields.
Comments:
23 pages, 11 figures, paper accepted by Nuclear Physics B
Subjects:
General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
arXiv:
2502.10247 [pdf]
NPB(2025)·1 citation

Affiliations

first authorsco-authorsvia INSPIRE