Nuclear Theory·nucl-th

Friday·April 21, 2023

15 papers—5 primary·10 cross-listed

01
[Submitted on 20 Apr 2023]
Improving nuclear data evaluations with predictive reaction theory and indirect measurements
Jutta Escher🇺🇸 · Kirana Bergstrom🇺🇸 · Emanuel Chimanski🇺🇸 · Oliver Gorton🇺🇸 · Eun Jin In🇺🇸 · Michael Kruse🇺🇸 · Sophie Péru🇫🇷 · Cole Pruitt🇺🇸 · Rida Rahman🇺🇸 · Emily Shinkle🇺🇸 · Aaina Thapa🇺🇸 · Walid Younes🇺🇸
Nuclear reaction data required for astrophysics and applications is incomplete, as not all nuclear reactions can be measured or reliably predicted. Neutron-induced reactions involving unstable targets are particularly challenging, but often critical for simulations. In response to this need, indirect approaches, such as the surrogate reaction method, have been developed. Nuclear theory is key to extract reliable cross sections from such indirect measurements. We describe ongoing efforts to expand the theoretical capabilities that enable surrogate reaction measurements. We focus on microscopic predictions for charged-particle inelastic scattering, uncertainty-quantified optical nucleon-nucleus models, and neural-network enhanced parameter inference.
Comments:
4 pages, 4 figures, proceedings contribution for Nuclear Data 2022
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2304.10034 [pdf]
EPJ Web Conf.(2023)·2 citations
02
[Submitted on 20 Apr 2023]
Probing the nucleon effective mass splitting with the light particle emission
Fang-Yuan Wang · Jun-Ping Yang · Xiang Chen · Ying Cui · Yong-Jia Wang · Zhi-Gang Xiao · Zhu-Xia Li · Ying-Xun Zhang
In this work, we first analyze the correlations among different nuclear matter parameters which are obtained by the 119 effective Skyrme interaction sets. The values of the correlation coefficients illustrate that the magnitude of the effective mass splitting is crucial for the tight constraints of the symmetry energy via HICs. Thus, the main object of this work is to investigate the impacts of the effective mass splitting on the heavy ion collisions observables. The $^{86}$ Kr+ $^{208}$ Pb system at the beam energy ranging from 25A MeV to 200A MeV are simulated within the framework of the improved quantum molecular dynamics model (ImQMD-Sky) for this goal. Our calculations show that the slopes of the spectra of $ln$ [Y(n)/Y(p)] and $ln$ [Y(t)/Y( $^{3}$ He)], which are the logarithms of the neutron to proton yield ratios and triton to Helium-3 yield ratios, are directly related to the effective mass splitting and can be used to probe the effective mass splitting.
Comments:
9 pages, 4 figures
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2304.10171 [pdf]
Nucl.Sci.Tech.(2023)·15 citations
03
[Submitted on 20 Apr 2023]
Study of S, Cl and Ar isotopes with $N \geq Z$ using microscopic effective $s d$ -shell interactions
Priyanka Choudhary · Praveen C. Srivastava
In the present work, newly developed microscopic effective $s d$ -valence shell interactions such as chiral next-to-next-to-next-to-leading order (N3LO), $J$ -matrix inverse scattering potential (JISP16), Daejeon16 (DJ16), and monopole-modified DJ16 (DJ16A) are employed to study the nuclear structural properties of sulphur, chlorine, and argon isotopes with $N \geq Z$ . These interactions are derived using the \textit{ab initio} no-core shell-model and the OLS unitary transformation method. We calculate energy spectra and electromagnetic properties to test the predictive strength of the effective interactions for these heavier $s d$ -shell nuclei. For a complete systematic study, we compare the microscopic results with the phenomenological USDB results and experimental data. By looking at the excitation energies of these nuclei, the DJ16A interaction is found to be {the} most suitable for these $s d$ -shell nuclei among all microscopic interactions. The electric quadrupole transition strength and excitation energy of the first $2^{+}$ state data of even-even sulphur isotopes indicate the presence of the $N = 20$ shell closure. Quadrupole moment predictions are also made using these interactions where experimental data are unknown. Magnetic moments are in excellent agreement with the experimental values. The root-mean-square deviations are also calculated to provide an idea of how accurate the interactions are.
Comments:
14 pages, 7 figures, The European Physical Journal A-Hadrons and Nuclei (accepted)
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2304.10361 [pdf]
EPJA(2023)·6 citations
04
[Submitted on 20 Apr 2023]
Self-consistent calculations for atomic electron capture
V. A. Sevestrean · O. Niţescu · S. Ghinescu · S. Stoica
We present a comprehensive investigation of electron capture (EC) ratios spanning a broad range of atomic numbers. The study employs a self-consistent computational method that incorporates electron screening, electron correlations, overlap and exchange corrections, as well as shake-up and shake-off atomic effects. The electronic wave functions are computed with the Dirac-Hartree-Fock-Slater (DHFS) method, chosen following a systematic comparison of binding energies, atomic relaxation energies and Coulomb amplitudes against other existing methods and experimental data. A novel feature in the calculations is the use of an energy balance employing atomic masses, which avoids approximating the electron total binding energy and allows a more precise determination of the neutrino energy. This leads to a better agreement of our predictions for capture ratios in comparison with the experimental ones, especially for low-energy transitions. We expand the assessment of EC observables uncertainties by incorporating atomic relaxation energy uncertainties, in contrast to previous studies focusing only on Q-value and nuclear level energies. Detailed results are presented for nuclei of practical interest in both nuclear medicine and exotic physics searches involving liquid Xenon detectors ( $^{67} Ga$ , $^{111} In$ , $^{123} I$ , $^{125} I$ and $^{125} Xe$ ). Our study can be relevant for astrophysical, nuclear, and medical applications.
Comments:
16 pages, 9 figures, 4 tables
Subjects:
Nuclear Theory (nucl-th); Atomic Physics (physics.atom-ph)
arXiv:
2304.10373 [pdf]
PRA(2023)·12 citations
05
[Submitted on 19 Apr 2023]
Real and Imaginary Phase Shifts for Nucleon-Deuteron Scattering using Phase Function Method
Shikha Awasthi · O. S. K. S. Sastri
The neutron-deuteron (nd) and proton-deuteron (pd) scattering are the simplest nucleon-nucleus scenario which throws light on understanding few body systems. In this work, real and imaginary parts of scattering phase shifts (SPS) for nd and pd scattering are obtained using optical potential, with Malfliet-Tjon (MT) model of interaction, by phase function method (PFM). The SPS for doublet 2S1/2 and quartet 4S3/2 states of nd and pd systems have been obtained for real and imaginary parts separately by solving the phase equation for l= 0, using Runge-Kutta 5 th order technique for laboratory energies up to 19 M eV . The obtained (real,imaginary) SPS for 2S1/2 and 4S3/2 states are matching with standard data with mean absolute error (MAE) of (1.32, 0.06) for 2S1/2 state and (0.19, 0.06) for 4S3/2 state of nd scattering, (1.47,0.62) for 2S1/2 state and (0.55, 0.14) for 4S3/2 state of pd scattering.
Comments:
13 pages, 4 Figures and 3 Tables
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2304.10478 [pdf]
Phys.Atom.Nucl.(2024)·16 citations
06
[Submitted on 16 Jan 2023] (cross-list from gr-qc)
Neutron Stars in Modified Teleparallel Gravity
S. G. Vilhena🇧🇷 · S. B. Duarte🇧🇷 · M. Dutra🇧🇷 · P. J. Pompeia🇧🇷
We investigate compact objects in modified teleparallel gravity with realistic equations of state. We propose a modification of Teleparallel Equivalent to General Relativity, then an appropriate tetrad is applied to the field equations. A specific set of relations showing an equivalency between our gravitational model and the New General Relativity is found. The conservation equation implies that our Tolman-Oppenheimer-Volkoff equations are presented with an effective gravitational coupling constant. Numerical analysis using realistic equations of state is made, and the behavior of mass, radius, and the relation mass-radius as functions of a free parameter of our model is also investigated.
Comments:
9 pages, 5 figures
Subjects:
General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2301.06432 [pdf]
JCAP(2023)·13 citations
07
[Submitted on 14 Apr 2023] (cross-list from gr-qc)
Dark matter effects in modified teleparallel gravity
S. G. Vilhena🇧🇷 · M. Dutra🇧🇷 · O. Lourenço🇧🇷 · P. J. Pompeia🇧🇷
This work investigates dark matter (DM) effects in compact objects in modified teleparallel gravity (MTG) in which a modification of Teleparallel Equivalent to General Relativity is used. We applied a tetrad to the modified field equations where a set of relations is found. The conservation equation allows us to rewrite our Tolman-Oppenheimer-Volkoff equations with an effective gravitational coupling constant. As input to these new equations, we use a relativistic mean-field (RMF) model with dark matter content included, obtained from a Lagrangian density with both, hadronic and dark particle degrees of freedom, as well as the Higgs boson, used as a mediator in both sectors of the theory. Through numerical calculations, we analyze the mass-radius diagrams obtained from different parametrizations of the RMF-DM model, generated by assuming different values of the dark particle Fermi momentum and running the free parameter coming from the MTG. Our results show that it is possible for the system simultaneously support more DM content, and be compatible with recent astrophysical data provided by LIGO and Virgo Collaboration, as well as by NASA's Neutron star Interior Composition Explorer (NICER).
Comments:
8 pages, 2 figures
Subjects:
General Relativity and Quantum Cosmology (gr-qc); High Energy Astrophysical Phenomena (astro-ph.HE); Nuclear Theory (nucl-th)
arXiv:
2304.07364 [pdf]
PRD(2023)·4 citations
08
[Submitted on 18 Apr 2023] (cross-list from hep-ph)
Soft gluon self-energy at finite temperature and density: hard NLO corrections in general covariant gauge
Tyler Gorda🇩🇪 · Risto Paatelainen🇫🇮 · Saga Säppi🇩🇪 · Kaapo Seppänen🇫🇮
We compute the next-to-leading order (NLO) hard correction to the gluon self-energy tensor with arbitrary soft momenta in a hot and/or dense weakly coupled plasma in Quantum Chromodynamics. Our diagrammatic computations of the two-loop and power corrections are performed within the hard-thermal-loop (HTL) framework and in general covariant gauge, using the real-time formalism. We find that after renormalization our individual results are finite and gauge-dependent, and they reproduce previously computed results in Quantum Electrodynamics in the appropriate limit. Combining our results, we also recover a formerly known gauge-independent matching coefficient and associated screening mass in a specific kinematic limit. Our NLO results supersede leading-order HTL results from the 1980s and pave the way to an improved understanding of the bulk properties of deconfined matter, such as the equation of state.
Comments:
37 pages, 3 figures, matches with published version
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2304.09187 [pdf]
JHEP(2023)·16 citations
09
[Submitted on 18 Apr 2023] (cross-list from hep-ph)
Coulomb Corrections for Coherent Neutrino Nucleus Scattering
Ryan Plestid🇺🇸
In this work we consider sub-leading $O (Z^{2} α^{3})$ corrections to coherent elastic neutrino nucleus scattering (CEvNS). These corrections are not negligible by power counting since nuclei with large coherent cross sections have sizeable nuclear charges e.g.\ $Z α \sim 0.4$ . We find that the corrections are much smaller than naive power counting in $Z α$ would suggest and that Coulomb corrections do not substantially alter predictions for CEvNS in the Standard Model. We comment on similarities to older literature on mesonic and muonic atoms.
Comments:
3 pages, 2 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th); Atomic Physics (physics.atom-ph)
arXiv:
2304.09241 [pdf]
JHEP(2025)·1 citation
10
[Submitted on 18 Apr 2023] (cross-list from hep-ph)
Propagation of gauge fields in hot and dense plasmas at higher orders
Andreas Ekstedt🇩🇪
Thermal field theory is indispensable for describing hot and dense systems. Yet perturbative calculations are often stymied by a host of energy scales, and tend to converge slowly. This means that precise results require the apt use of effective field theories. In this paper we refine the effective description of slowly varying gauge field known as hard thermal loops. We match this effective theory to the full theory to two-loops. Our results apply for any renormalizable model and fermion chemical potential. We also discuss how to consistently define asymptotic masses at higher orders; and how to treat spectral functions close to the lightcone. In particular, we demonstrate that the gluon mass is well-defined to next-to-leading order.
Comments:
21 pages, 4 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2304.09255 [pdf]
11 citations
11
[Submitted on 19 Apr 2023] (cross-list from hep-ph)
Khuri-Treiman analysis of $J / ψ \to π^{+} π^{-} π^{0}$
JPAC Collaboration: M. Albaladejo🇪🇸 · S. Gonzàlez-Solís🇺🇸 · Ł. Bibrzycki🇵🇱 · C. Fernández-Ramírez🇪🇸 · N. Hammoud🇵🇱 · V. Mathieu🇪🇸 · M. Mikhasenko🇩🇪 · G. Montaña🇺🇸 · R. J. Perry🇪🇸 · A. Pilloni🇮🇹 · A. Rodas🇺🇸 · W. A. Smith🇺🇸 · A. Szczepaniak🇺🇸 · D. Winney🇨🇳
We study the decay $J / ψ \to π^{+} π^{-} π^{0}$ within the framework of the Khuri-Treiman equations. We find that the BESIII experimental di-pion mass distribution in the $ρ (770)$ -region is well reproduced with a once-subtracted $P$ -wave amplitude. Furthermore, we show that $F$ -wave contributions to the amplitude improve the description of the data in the $π π$ mass region around 1.5 GeV. We also present predictions for the $J / ψ \to π^{0} γ^{*}$ transition form factor.
Comments:
20 pages, 9 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Theory (nucl-th)
arXiv:
2304.09736 [pdf]
PRD(2023)·12 citations
12
[Submitted on 19 Apr 2023] (cross-list from hep-ph)
Transvese momentum dependent parton distributions of pion at leading twist
Wei Kou🇨🇳 · Chao Shi🇨🇳 · Xurong Chen🇨🇳 · Wenbao Jia🇨🇳
We calculate the leading twist pion unpolarized transverse momentum distribution $f_{1} (x, k_{T}^{2})$ and the Boer-Mulders function $h_{1}^{⊥} (x, k_{T}^{2})$ , using leading Fock-state light front wave functions (LF-LFWFs) based on Dyson-Schwinger and Bethe-Salpeter equations. These DS-BSEs based LF-LFWFs provide dynamically generated s- and p-wave components, which are indispensable in producing chirally odd Boer-Mulders function that has one parton spin flipped. Employing a non-perturbative SU(3) gluon rescattering kernel to treat the gauge link of the Boer-Mulders function, we thus obtain both TMDs at hadronic scale and then evolve them to the scale of $μ^{2} = 4.0$ GeV $^{2}$ . We finally calculate the generalized Boer-Mulders shift and find it to be in agreement with the lattice prediction.
Comments:
20 pages, 5 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2304.09814 [pdf]
PRD(2023)·14 citations
13
[Submitted on 19 Apr 2023] (cross-list from hep-ph)
Energy loss of heavy quarks in the presence of magnetic field
Mohammad Yousuf Jamal🇮🇳 · Jai Prakash🇮🇳 · Indrani Nilima🇮🇳 · Aritra Bandyopadhyay🇩🇪
We study the heavy quark energy loss in the presence of a background magnetic field. The analysis considers the high magnetic field generated by spectators from initial hard collisions that were incorporated using the medium-modified Debye mass, determined from quark condensates at finite temperature and magnetic field via recent lattice quantum chromodynamics (LQCD) calculations. We analyse the impact of medium polarization on the heavy quark propagation in a quark-gluon plasma formed in relativistic heavy-ion colliders like RHIC and LHC. For simplification, we considered the static medium with constant temperature and magnetic field values. Then, we explore the nuclear modification factor ( $R_{AA}$ ) at different magnitudes of magnetic field strengths at fixed temperatures. The energy loss of heavy quarks significantly increases, leading to $R_{AA}$ suppression at higher magnetic field values
Comments:
10 pages, 06 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2304.09851 [pdf]
J.Phys.G(2024)·17 citations
14
[Submitted on 20 Apr 2023] (cross-list from hep-lat)
$Δ$ baryon spectroscopy in lattice QCD
Liam Hockley🇦🇺 · Waseem Kamleh🇦🇺 · Derek Leinweber🇦🇺 · Anthony Thomas🇦🇺
A variational analysis is performed within the framework of lattice QCD to extract the masses of the spin-3/2 positive parity $Δ^{+}$ baryons, including radial excitations. $2 + 1$ flavour dynamical gauge-field configurations provided by the PACS-CS collaboration via the ILDG are considered. To improve our interpolator basis, we perform an iterative process of source and sink smearing and solve a generalised eigenvalue problem using the resulting fermion operators. We obtain a clear signal for the ground and first excited states at a light quark mass corresponding to $m_{π} = 413$ MeV. Furthermore, we show that one can use the eigenvectors obtained in this method to investigate the nature of these states, allowing us to classify our results as $1 s$ and $2 s$ states for the ground and first excited states respectively. Finally, we briefly highlight the method of Hamiltonian Effective Field Theory which can be used to make comparison with quark model expectations.
Comments:
12 pages, 3 figures. Contribution to a special issue of Few Body Systems: "Emergence and Structure of Baryons -- Selected Contributions from the International Conference Baryons 2022"
Subjects:
High Energy Physics — Lattice (hep-lat); Nuclear Theory (nucl-th)
arXiv:
2304.10187 [pdf]
Few Body Syst.(2023)·3 citations
15
[Submitted on 20 Apr 2023] (cross-list from hep-ph)
Exploring the axion potential and axion walls in dense quark matter
Bonan Zhang🇨🇳 · David E. A. Castillo🇵🇱 · Ana G. Grunfeld🇦🇷 · Marco Ruggieri🇮🇹
We study the potential of the Quantum Chromodynamics axion in hot and/or dense quark matter, within a Nambu-Jona-Lasinio-like model that includes the coupling of the axion to quarks. Differently from previous studies, we implement local electrical neutrality and $β -$ equilibrium, which are relevant for the description of the quark matter in the core of compact stellar objects. Firstly we compute the effects of the chiral crossover on the axion mass and self-coupling. We find that the low energy properties of axion are very sensitive to the phase transition of Quantum Chromodynamics, in particular, when the bulk quark matter is close to criticality. Then, for the first time in the literature we compute the axion potential at finite quark chemical potential and study the axion domain walls in bulk quark matter. We find that the energy barrier between two adjacent vacuum states decrease in the chirally restored phase: this results in a lower surface tension of the walls. Finally, we comment on the possibility of production of walls in dense quark matter.
Comments:
10 pages, 7 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
2304.10240 [pdf]
PRD(2023)·14 citations

Affiliations

first authorsco-authorsvia INSPIRE