Nuclear Theory·nucl-th

Wednesday·January 17, 2024

26 papers—9 primary·17 cross-listed

01
Folding potential with modern nuclear density functionals and application to 16O+208Pb reaction
Kyoungsu Heo · Hana Gil · Ki-Seok Choi · K. S. Kim · Chang Ho Hyun · W. Y. So
Double folding potential is constructed using the M3Y interaction and the matter densities of the projectile and target nuclei obtained from four microscopic energy density functional (EDF) models. The elastic scattering cross sections for the 16O+208Pb system are calculated using the optical model with the double folding potentials of the four EDF models. We focus on the correlation between the matter densities and the behavior the double folding potential and the elastic scattering cross sections. First, the matter and charge densities are examined by comparing the results of the four EDF models. There is a slight difference in the density in the internal region, but it is negligible in the outer region. Next, we calculate the double folding potential with the matter densities obtained from the four EDF models. Differences between the models are negligible in the outer region, but the potential depth in the internal region shows model dependence, which can be understood from the behavior of matter densities in the internal region. Another point is that the double folding potential is shown to be weakly dependent on the incident energy. Finally, the elastic scattering cross sections have no significant model dependence except for the slight difference in the backward angle.
nucl-thPRC(2024)·0 citations
02
Isospin splitting of the Dirac mass probed by the relativistic Brueckner-Hartree-Fock theory in the full Dirac space
Pianpian Qin · Qiang Zhao · Hui Tong · Chencan Wang · Sibo Wang
The isospin splitting of the Dirac mass obtained with the relativistic Brueckner-Hartree-Fock (RBHF) theory is thoroughly investigated. From the perspective in the full Dirac space, the long-standing controversy between the momentum-independence approximation (MIA) method and the projection method on the isospin splitting of the Dirac mass in asymmetric nuclear matter (ANM) is analyzed in detail. We find that, the \textit{assumption procedure} of the MIA method, which assumes that the single-particle potentials are momentum independent, is not a sufficient condition that directly leads to the wrong sign of the isospin splitting of the Dirac mass, while the \textit{extraction procedure} of the MIA method, which extracts the single-particle potentials from the single-particle potential energy, leads to the wrong sign. By approximately solving the set of equations involved in the \textit{extraction procedure}, a formal expression of the Dirac mass is obtained. The wrong isospin splitting of the Dirac mass is mainly caused by that the \textit{extraction procedure} forcely assumes the momentum dependence of the single-particle potential energy to be a quadratic form where the strength is solely determined by the constant scalar potential.
nucl-thNucl.Sci.Tech.(2025)·8 citations
03
Weak magnetic effect in quark-gluon plasma and local spin polarization
Jing-An Sun🇨🇳 · Li Yan🇨🇳
We propose the weak magnetic effect, which emerges in quark-gluon plasma close to local thermal equilibrium as the dissipative correction to the quark phase space distribution function, as a novel contribution to the observed Lambda hyperon local spin polarization. With a finite field strength, which is consistent with previous estimate of the magnetic field in heavy-ion collisions, one is able to explain the experimentally observed Lambda local spin polarization through all centrality classes. Moreover, the weak magnetic effect plays an unambiguous role in the ordering between the second-order and the third-order modulations of the Lambda local spin polarization in experiments.
nucl-thhep-phnucl-exCPC(2025)·10 citations
04
Calculation of Fission Fragment Yields for thermal neutron reaction of $^{239}$ Pu
Futoshi Minato
Fission fragment yield evaluation in the past has been done mainly by considering independent and cumulative fission yields. In addition to them, the fission fragment yields are related to various observables such as total kinetic energy, prompt fission neutron, decay heats, etc. Various improvements were carried out in the fission fragment yield evaluation of JENDL-5, however it did not consider correlations between such fission observables and fragment yields. A new evaluation including fission observables is thus required for next generation of evaluated data. We recently developed a new calculation system using CCONE code to calculate fission fragment yields. This calculation system enables us to compare various fission observables with the experimental data simultaneously. In this work, we calculated thermal-induced fission of 239Pu. We present the result of prompt fission neutrons, decay heats, and delayed neutrons
nucl-thnucl-ex0 citations
05
Correlation of the hyperon potential stiffness with hyperon constituents in neutron stars and heavy-ion collisions
Si-Na Wei🇨🇳 · Zhao-Qing Feng🇨🇳 · Wei-Zhou Jiang🇨🇳
The breaking of SU(6) symmetry to a more general flavor SU(3) symmetry could serve as a potential explanation for the "hyperon puzzle" of neutron stars by adjusting the hyperon potentials. Specifically, when the soft relativistic mean-field (RMF) $Λ$ hyperon potentials fall within the domains of chiral SU(3) interactions NLO13 with two-body forces, the maximum mass of neutron stars is expected to be lower than 2.0 $M_{⊙}$ , whereas it can exceed $2.0 M_{⊙}$ if the RMF $Λ$ hyperon potentials are sufficiently stiff to be consistent with those from chiral SU(3) interactions NLO13 with three-body forces. In our investigation involving these two types of $Λ$ hyperon potentials, we explore how the hyperon yields and flows are affected in heavy-ion collisions. We find that the inclusion of hyperon potentials results in better agreement of the $Λ$ directed flows with data but without clear differentiation in the stiffness of the hyperon potentials. Similarly negligent is the disparity in the rapidity distributions of the $Λ$ collective flows predicted by the stiff and soft hyperon potentials. In contrast, the $Λ$ collective flows beyond the central rapidity region turn out to be sensitive to the stiffness of the RMF equation of state (EOS) with the preference of a soft RMF EOS to a stiff one. Notably, the transverse momentum distributions of $Λ$ hyperon production are sensitive to both the stiffness of the RMF EOS and $Λ$ hyperon potential at high transverse momenta.
nucl-thPLB(2024)·14 citations
06
Radial Oscillations of Hybrid Stars and Neutron Stars including Delta baryons: The Effect of a Slow Quark Phase Transition
Ishfaq Ahmad Rather🇩🇪 · Kauan D. Marquez🇵🇹 · Betania C. Backes🇬🇧 · Grigoris Panotopoulos🇨🇱 · Ilidio Lopes🇵🇹
We study radial oscillations of hybrid neutron stars composed of hadronic external layers followed by a quark matter core. We employ a density-dependent relativistic mean-field model including hyperons and $Δ$ baryons to describe hadronic matter, and a density-dependent quark model for quark matter. We obtain the ten lowest eigenfrequencies and the corresponding oscillation functions of N, N+ $Δ$ , N+H, and N+H+ $Δ$ equations-of-state with a phase transition to the quark matter at 1.4 and 1.8 $M_{⊙}$ , focusing on the effects of a slow phase transition at the hadron-quark interface. We observe that the maximum mass is reached before the fundamental mode's frequency vanishes for slow phase transitions, suggesting that some stellar configurations with higher central densities than the maximum mass remain stable even when they undergo small radial perturbations. Future gravitational wave detectors and multi-messenger astronomy, complemented by robust microscopic models enabling exploration of various neutron star compositions, including hyperon content, are anticipated to impose precise limitations on the equation of state of baryonic matter under high-density conditions.
nucl-thastro-ph.HEJCAP(2024)·23 citations
07
Shell effects on the drift and fluctuation in multinucleon transfer reactions
Zehong Liao · Zepeng Gao · Yu Yang · Jun Su · Long Zhu
This study employs the dinuclear system model (DNS-sysu) to investigate drift and fluctuation mechanisms in 136Xe + 209Bi collisions above the Coulomb barrier. The DNS-sysu model demonstrated its effectiveness in providing reasonable descriptions of drift and fluctuation dynamics for the multinucleon transfer reaction at low energies. We observe temperature-induced changes in the shell effect, impacting nucleon transfer. At higher energies, the weakening constraint of the potential energy surface leads to a reversal in the evolution direction. Additionally, the consideration of shell corrections notably affects fragment distribution at low energies but diminishes for high-energy conditions. This research provides valuable insights into understanding the macroscopic manifestation of nucleon transfer in the multinucleon transfer reaction.
nucl-thPRC(2024)·11 citations
08
Constraints on the isovector properties of finite nuclei from neutron stars observations
M. Divaris · A. Kanakis-Pegios · Ch.C. Moustakidis
The nuclear symmetry energy plays important role on the structure of finite nuclei as well as on the bulk properties of neutron stars. However, its values at high densities are completely uncertain and the corresponding experimental data have a large error. One possibility to determine or at least estimate the values at high densities is with the help of neutron star observations. Recently, observations of gravitational waves from merging processes of binary neutron star systems provide useful information on both their radius and tidal deformability, quantities directly related to the symmetry energy. In this work, an attempt is made in this direction, namely to see how recent observations can help to constrain the structure of finite nuclei. In particular, in the present study we parameterize the equation of state which describes the asymmetric and symmetric nuclear mater with the help of the parameter $η = (K_{0} L^{2})^{1/3}$ , where $K_{0}$ is the incompressibility and $L$ the slope parameter. The parameter $η$ is a regulator of the stiffness of the equation of state. We expect that the values of $η$ affect both the properties of finite nuclei as well as of the neutron star properties (where the role of the isovector interaction plays important role). It is natural to expect that constraints, via the parameter $η$ on finite nuclei will imply constraints on the neutron star properties and vice versa. In view of the above statements we propose a simple but self-consistent method to examine simultaneously the effects of the parameter $η$ on the properties of finite nuclei and neutron stars. We found constraints on the latter systems via combination by the recent experiments (PREX-2) and observational data found by the detectors Ligo and Virgo.
nucl-thastro-ph.HEastro-ph.SRnucl-exPRC(2024)·9 citations
09
Exploring Radial Oscillations in Slow Stable and Hybrid Neutron Stars
Sayantan Ghosh · Sailesh Ranjan Mohanty · Tianqi Zhao · Bharat Kumar
In the era of gravitational wave astronomy, radial oscillations hold significant potential for not only uncovering the microphysics behind the internal structure but also investigating the stability of neutron stars (NSs). We start by constructing families of static NSs following nucleonic, quarkyonic, and hybrid equations of state and then subject them to radial perturbations in order to explore the stability of these stars. Unlike other literature where the fluid elements are assumed to be in chemical equilibrium, we consider the out-of-equilibrium effects on the chemical composition of fluid elements for the calculation of radial modes. Taking these considerations into account, we observe that the sound speed ( $c_{s}^{2}$ ) and adiabatic index ( $γ$ ) avoid singularities and discontinuities over the equilibrium case. We elucidate the response of the fundamental radial modes by examining the out-of-equilibrium matter distribution scenario, offering insights into its dynamic variations. We also demonstrate that this approach extends the stable branches of stellar models, enabling stars to sustain stable higher-order mass doublets, shedding some light on observation and existence of PSR J0740+6620.
nucl-thastro-ph.GAgr-qcJCAP(2025)·9 citations
10
An alternative to perturbative renormalization in 3+1 dimensional field theories
Paul Romatschke🇺🇸
Perturbative renormalization provides the bedrock of understanding quantum field theories. In this work, I point out an alternative way of renormalizing quantum field theories, which is naturally encountered and well known for the case of large N scalar field theories. In terms of bare parameters, this non-perturbative alternative renormalization differs qualitatively from its perturbative cousin: in the continuum limit, the bare coupling constant goes to zero instead of infinity, and there is no wave-function counterterm. Despite these differences, the resulting n-point functions of the theory are finite. I provide explicit results for alternative renormalization for the O(N) model and QCD with $N_{f} = 12$ flavors in 3+1 dimensions.
↳ hep-thhep-phnucl-thPRD(2024)·8 citations
11
Mini-jet Clustering Algorithm Using Transverse-momentum Seeds in High-energy Nuclear Collisions
Hanpu Jiang🇺🇸 · Nanxi Yao🇺🇸 · Cheuk-Yin Wong🇺🇸 · Gang Wang🇺🇸 · Huan Zhong Huang🇺🇸
We propose an algorithm to detect mini-jet clusters in high-energy nuclear collisions, by selecting a high-transverse-momentum ( $p_{T}$ ) particle as a seed and assigning a clustering radius ( $R$ ) in the pseudorapidity and azimuthal-angle space. Our PYTHIA simulations for $p$ + $p$ collisions show that a scheme with a seeding $p_{T}$ of around 0.5 GeV/ $c$ and $R$ of approximately 0.6 satisfactorily identifies mini-jet clusters. The correlation between clusters obtained in PYTHIA calculations using the algorithm exhibits the proper behavior of hard-scattering-like processes, suggesting its usefulness in isolating mini-jet-like clusters from non-hard-scattering soft processes when applied to actual nuclear-collision data, thereby allowing a closer examination of both the mini-jet and the soft mechanisms.
↳ physics.data-annucl-exnucl-thPRC(2024)·0 citations
12
Quantum Chromodynamics of the Nucleon in the Framework of Complex Probabilistic Processes
A.S. Gevorkyan🇦🇲 · A.V. Bogdanov🇷🇺
Soon after the postulation of quarks by Gell-Mann, Zweig and Fritzsch the experimental confirmation of these sub-nucleon formations, Feynman, Ravndal and Kislinger proposed a relativistic three-quark model of the nucleon to study its internal structure and state. Despite the obvious progress in describing the internal motion of a system with confinement of quarks in a nucleon, it should be stated that the model is not realistic enough. The fact is that the model ignores the processes of gluon exchange between quarks, as well as the influence of continuously formed pairs of quarks and antiquarks (quark sea) on valence quarks. To overcome this difficulty, the problem of self-organization of a three-quark dynamical system immersed in a colored quark-antiquark sea is considered within the framework of the representation of complex probabilistic processes satisfying the stochastic differential equation of Langevin-Kline-Gordon-Fock type. Taking into account the hidden symmetry of the internal motion of a dynamical system, a mathematically closed non-perturbative approach has been developed, which makes it possible to construct the mathematical expectation of the wave function and other parameters of the nucleon in the form of multiple integral representations. The developed approach can be especially useful for studying the state of nucleons in critical states, which occurs, for example, in massive and dense stellar formations such as neutron stars, etc.
↳ hep-phnucl-thSymmetry(2024)·1 citation
13
A Possible Mechanism to Alter Gyromagnetic Factor
Jing-Ling Chen🇨🇳 · Xing-Yan Fan🇨🇳 · Xiang-Ru Xie🇨🇳
Dirac has predicted that the $g$ factor of an electron is strictly equal to 2 in the framework of relativistic quantum mechanics. However, later physicists have found that this factor can be slightly deviated from 2 (i.e., the problem of anomalous magnetic moments of leptons) when they consider quantum filed theory. This fact thus renders the $g$ factors of free leptons serving as precision tests for quantum electrodynamics, the standard model and beyond. In this work, we re-examine the problem of $g$ factor within the framework of relativistic quantum mechanics. We propose a possible mechanism called the ``electron-braidon mixing'', such that the $g$ factor of an electron can be visibly altered. Our results are hopeful to be verified in experiments and also shed new light to the problem of the anomalous magnetic moments of leptons.
↳ hep-phhep-thnucl-thquant-phResults Phys.(2025)·0 citations
14
Stability constraint for spin equation of state
Asaad Daher🇵🇱 · Wojciech Florkowski🇵🇱 · Radoslaw Ryblewski🇵🇱
A generalized Frenkel condition is proposed for use in spin hydrodynamics to relate the spin density and spin polarization (or spin chemical potential) tensors. It allows for independent treatment of electric- and magnetic-like components of the spin density tensor, which helps to fulfill the stability conditions recently derived in the literature. The generalized Frenkel condition extrapolates between the original Frenkel condition, where only the magnetic-like part of the spin tensor is present, and the case where the spin density tensor is directly proportional to the spin polarization tensor. We also demonstrate that our approach is supported by the result of a microscopic calculation.
↳ hep-phnucl-thPRD(2024)·15 citations
15
Fusion of $^{7}$ Li with $^{205}$ Tl at near barrier energies
V. V. Parkar · Prasanna M. · Ruchi Rathod · V. Jha · S. K. Pandit · A. Shrivastava · K. Mahata · K. Ramachandran · R. Palit · Md. S. R. Laskar · B. J. Roy · Bhushan Kanagalekar · B. G. Hegde
The complete and incomplete fusion cross sections for the $^{7}$ Li+ $^{205}$ Tl reaction were measured at near barrier energies by online characteristic $γ$ ray detection technique. The complete fusion (CF) cross sections at energies above the Coulomb barrier were found to be suppressed by $\sim$ 26 \% compared to the coupled channel calculations. Reduced fusion cross sections for the present system at energies normalised to the Coulomb barrier were also found to be systematically lower than those with strongly bound projectiles forming a similar compound nucleus. The suppression observed in CF cross sections is found to be commensurate with the measured total incomplete fusion (ICF) cross sections. In the ICF cross sections, t capture is found to be dominant than $α$ capture at all the measured energies. The systematic study of available CF, ICF and total fusion (TF) data with $^{7}$ Li projectile is performed.
↳ nucl-exnucl-thPRC(2024)·11 citations
16
Chiral magnetic waves in strongly coupled Weyl semimetals
Yongjun Ahn🇨🇳 · Matteo Baggioli🇨🇳 · Yan Liu🇨🇳 · Xin-Meng Wu🇨🇳
Propagating chiral magnetic waves (CMW) are expected to exist in chiral plasmas due to the interplay between the chiral magnetic and chiral separation effects induced by the presence of a chiral anomaly. Unfortunately, it was pointed out that, because of the effects of electric conductivity and dissipation, CMW are overdamped and therefore their signatures are unlikely to be seen in heavy-ion collision experiments and in the quark gluon plasma. Nonetheless, the chiral anomaly plays a fundamental role in Weyl semimetals and their anomalous transport properties as well. Hence, CMW could be potentially observed in topological semimetals using table-top experiments. By using a holographic model for strongly coupled Weyl semimetals, we investigate in detail the nature of CMW in presence of Coulomb interactions and axial charge relaxation and estimate whether, and in which regimes, CMW could be observed as underdamped collective excitations in topological materials.
↳ hep-thcond-mat.str-elnucl-thJHEP(2024)·10 citations
17
Towards Uncovering Dark Matter Effects on Neutron Star Properties: A Machine Learning Approach
Prashant Thakur🇮🇳 · Tuhin Malik🇵🇹 · T. K. Jha🇮🇳
In recent years, researchers have become increasingly interested in understanding how dark matter affects neutron stars, helping them to better understand complex astrophysical phenomena. In this paper, we delve deeper into this problem by using advanced machine learning techniques to find potential connections between dark matter and various neutron star characteristics. We employ Random Forest classifiers to analyze neutron star (NS) properties and investigate whether these stars exhibit characteristics indicative of dark matter admixture. Our dataset includes 32,000 sequences of simulated NS properties, each described by mass, radius, and tidal deformability, inferred using recent observations and theoretical models. We explore a two-fluid model for the NS, incorporating separate equations of state for nucleonic and dark matter, with the latter considering a fermionic dark matter scenario. Our classifiers are trained and validated in a variety of feature sets, including the tidal deformability for various masses. Based on confusion matrices, these classifiers can identify NS with admixed dark matter with approximately 17% probability of misclassification. In particular, we find that additional tidal deformability data do not significantly improve the precision of our predictions. This article also delves into the potential of specific NS properties as indicators of the presence of dark matter. Radius measurements, especially at extreme mass values, emerge as particularly promising features. The insights gained from our study will guide future observational strategies and enhance dark matter detection capabilities. According to this study, neutron stars at 1.4 and 2.07 solar masses have radii that strongly suggest dark matter in neutron stars more likely than just hadronic composition, based on NICER data from pulsars PSR J0030+0451 and PSR J0740+6620.
↳ hep-phastro-ph.HEnucl-thParticles(2024)·18 citations
18
Unleashing the Power of EFT in Neutrino-Nucleus Scattering
Joachim Kopp🇨🇭 · Noemi Rocco🇺🇸 · Zahra Tabrizi🇺🇸
Neutrino physics is advancing into a precision era with the construction of new experiments, particularly in the few GeV energy range. Within this energy range, neutrinos exhibit diverse interactions with nucleons and nuclei. This study delves in particular into neutrino--nucleus quasi-elastic cross sections, taking into account both standard and, for the first time, non-standard interactions, all within the framework of effective field theory (EFT). The main uncertainties in these cross sections stem from uncertainties in the nucleon-level form factors, and from the approximations necessary to solve the nuclear many-body problem. We explore how these uncertainties influence the potential of neutrino experiments to probe new physics introduced by left-handed, right-handed, scalar, pseudoscalar, and tensor interactions. For some of these interactions the cross section is enhanced, making long-baseline experiments an excellent place to search for them. Our results, including tabulated cross sections for all interaction types and all neutrino flavors, can serve as the foundation for such searches.
↳ hep-phhep-exnucl-thJHEP(2024)·13 citations
19
Structure of Heavy Mesons in the Light-Front Quark Model
Ahmad Jafar Arifi🇯🇵 · Lucas Happ🇯🇵 · Shuhei Ohno🇯🇵 · Makoto Oka🇯🇵
We investigate the structure of ground-state heavy mesons within the light-front quark model, utilizing wave functions derived from the Single Gaussian Ansatz (SGA) and the Gaussian Expansion Method (GEM). By performing a $χ^{2}$ fit to static properties such as mass spectra and decay constants, we determine the model parameters for each approach. We then compare the impacts of both methods on the light-front wave functions and structural observables. Our analysis reveals significant differences in the distribution amplitudes (DAs) $ϕ_{2; M} (x)$ near the endpoints, with GEM showing enhanced amplitudes and correct asymptotic behavior $ϕ_{2; M} (x \to 1) \propto (1 - x)$ , consistent with perturbative QCD. This endpoint behavior is linked to the short-range (high-momentum) wave function governed by color Coulomb interaction and relativistic kinematics. GEM accurately reproduces a power-law damping $ψ_{0} (k \to \infty) \propto 1/ k_{⊥}^{2}$ , aligning with perturbative QCD predictions. Furthermore, the electromagnetic form factors of pseudoscalar mesons in the low- $Q^{2}$ region fall off faster with GEM than with SGA. Overall, while both methods adequately describe static properties, GEM provides a more accurate description of structural properties, being more sensitive to details and asymptotic behaviors.
↳ hep-phnucl-thPRD(2024)·26 citations
20
High-precision mass measurements of neutron deficient silver isotopes probe the robustness of the $N$ = 50 shell closure
Zhuang Ge · Mikael Reponen · Tommi Eronen · Baishan Hu · Markus Kortelainen · Anu Kankainen · Iain Moore · Dmitrii Nesterenko · Cenxi Yuan · Olga Beliuskina · Laetitia Cañete · Ruben de Groote and 27 other authors
High-precision mass measurements of exotic $^{95 - 97}$ Ag isotopes close to the $N = Z$ line have been conducted with the JYFLTRAP double Penning trap mass spectrometer, with the silver ions produced using the recently commissioned inductively-heated hot cavity catcher laser ion source at the Ion Guide Isotope Separator On-Line facility. The atomic mass of $^{95}$ Ag was directly determined for the first time. In addition, the atomic masses of $β$ -decaying 2 $^{+}$ and 8 $^{+}$ states in $^{96}$ Ag have been identified and measured for the first time, and the precision of the $^{97}$ Ag mass has been improved. The newly measured masses, with a precision of $\approx$ 1 keV/c $^{2}$ , have been used to investigate the $N =$ 50 neutron shell closure confirming it to be robust. Empirical shell-gap and pairing energies determined with the new ground-state mass data are compared with the state-of-the-art \textit{ab initio} calculations with various chiral effective field theory Hamiltonians. The precise determination of the excitation energy of the $^{96 m}$ Ag isomer in particular serves as a benchmark for \textit{ab initio} predictions of nuclear properties beyond the ground state, specifically for odd-odd nuclei situated in proximity to the proton dripline below $^{100}$ Sn. In addition, density functional theory (DFT) calculations and configuration-interaction shell-model (CISM) calculations are compared with the experimental results. All theoretical approaches face challenges to reproduce the trend of nuclear ground-state properties in the silver isotopic chain across the $N =$ 50 neutron shell and toward the proton drip-line.
↳ nucl-exnucl-thPRL(2024)·22 citations
21
Transport and Connection to Heavy-ion Collisions via Heavy Flavor Probes
Hai-Tao Shu🇺🇸
The heavy ion experiments in Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) are going through upgrade in the next five years, shifting their focus more on the hard processes in the new runs. One of the main goals is to draw a finer image for the quark gluon plasma (QGP). The heavy flavor probes , which witness the whole history of heavy ion collision are particularly sensitive to test the properties of QGP formed in such collisions. The lattice results for heavy flavor probes provide transport and phenomenological models crucial inputs to describe the experimental observations like the strong suppression of the nuclear modification factor $R_{AA}$ and the non-zero azimuthal anisotropy at low $p_{T}$ . In the last two years we have seen significant advances in the lattice QCD studies of heavy flavor probes, including the in-medium quarkonium properties, the complex static quark-antiquark potential and the heavy quark diffusion from lattice simulations at nonzero temperature. These achievements substantially deepen our understanding of the fate of quarkonium, the screening/unscreening of the complex potential and the temperature and quark mass dependence of the heavy quark diffusion in thermal medium. In these proceedings, we review recent results and briefly discuss possible directions in these studies.
↳ hep-lathep-phnucl-thPoS(2024)·2 citations
22
Quantum Simulations of Hadron Dynamics in the Schwinger Model using 112 Qubits
Roland C. Farrell🇺🇸 · Marc Illa🇺🇸 · Anthony N. Ciavarella🇺🇸 · Martin J. Savage🇺🇸
Hadron wavepackets are prepared and time evolved in the Schwinger model using 112 qubits of IBM's 133-qubit Heron quantum computer ibm_torino. The initialization of the hadron wavepacket is performed in two steps. First, the vacuum is prepared across the whole lattice using the recently developed SC-ADAPT-VQE algorithm and workflow. SC-ADAPT-VQE is then extended to the preparation of localized states, and used to establish a hadron wavepacket on top of the vacuum. This is done by adaptively constructing low-depth circuits that maximize the overlap with an adiabatically prepared hadron wavepacket. Due to the localized nature of the wavepacket, these circuits can be determined on a sequence of small lattices using classical computers, and then robustly scaled to prepare wavepackets on large lattices for simulations using quantum computers. Time evolution is implemented with a second-order Trotterization. To reduce both the required qubit connectivity and circuit depth, an approximate quasi-local interaction is introduced. This approximation is made possible by the emergence of confinement at long distances, and converges exponentially with increasing distance of the interactions. Using multiple error-mitigation strategies, up to 14 Trotter steps of time evolution are performed, employing 13,858 two-qubit gates (with a CNOT depth of 370). The propagation of hadrons is clearly identified, with results that compare favorably with Matrix Product State simulations. Prospects for a near-term quantum advantage in simulations of hadron scattering are discussed.
↳ quant-phhep-lathep-phnucl-thPRD(2024)·234 citations
23
Quenched Static force from generalized Wilson loops with gradient flow
Julian Mayer-Steudte🇩🇪
We compute the static force on the lattice in the quenched case directly through generalized Wilson loops. We modify the Wilson loop by inserting an $E$ -field component on one of the temporal Wilson lines. However, chromo-field components prevent us from performing the continuum limit properly, hence, we use gradient flow to renormalize the field insertion. As a result, we obtain continuum results and compare them to perturbative expression to extract $Λ_{0}$ , and we predict the value $8 t_{0} Λ_{MS}^{n_{f} = 0} = 0.62 9_{- 26}^{+ 22}$ . This work serves as preparation for similar operators with field insertions required in nonrelativistic effective field theories.
↳ hep-lathep-phhep-thnucl-thPoS(2024)·0 citations
24
Shear oscillations in neutron stars and the nuclear symmetry energy
Hajime Sotani
The shear and interface modes excited inside the neutron star due to the presence of elasticity depend on the properties of both the crust and core region. To examine how such eigenfrequencies depend on the neutron star properties, we solve the eigenvalue problem by adopting the relativistic Cowling approximation. Then, we confirm that the number of the interface modes excited in the star is generally equivalent to the number of the interface where the shear modulus discontinuously becomes zero, but we also find that the number of interface modes becomes smaller than that of the interface for the stellar model with lower or higher value of the slope parameter $L$ . Furthermore, we derive the empirical relations for expressing the shear modes and one of the interface modes ( $i_{1}$ -mode in the text), which is the mode whose amplitude becomes dominant at the interface between the crust and envelopes and at the interface between the phases of slablike and cylindrical nuclei. At the end, we also show the possibility of identifying the higher QPO frequencies observed in GRB 200415A with the shear oscillations, as an alternative possibility instead of the torsional oscillations.
↳ astro-ph.HEnucl-thPRD(2024)·10 citations
25
Probing the four-fermion operators via the transverse double spin asymmetry at the Electron-Ion Collider
Hao-Lin Wang🇨🇳 · Xin-Kai Wen🇨🇳 · Hongxi Xing🇨🇳 · Bin Yan🇨🇳
The chirality-flipping operators of light fermions are currently poorly constrained by experimental analyses due to the lack of interference with Standard Model (SM) amplitudes in traditional observables. In this work, we propose to investigate the semi-leptonic scalar/tensor four-fermion operators of electron and quarks through the transverse double spin asymmetry (DSA) at Electron-Ion Collider, where both the electron and proton beams could be highly transversely polarized. Due to the chirality-flipping nature of these operators, we demonstrate that their interference with the SM results in an unsuppressed contribution to the DSA, and could lead to non-trivial azimuthal $cos 2 ϕ$ and $sin 2 ϕ$ distributions that are linearly dependent on their Wilson coefficients. This new method has the potential to significantly improve the current constraints on these scalar/tensor four-fermion operators without relying on theoretical assumptions about other types of new physics effects, particularly for the tensor type operator of the $u$ -quark. Additionally, our findings indicate that both the real and imaginary parts of these operators can be simultaneously constrained and offer a new opportunity for probing potential $C P$ -violation effects. However, it is important to note that these results would be sensitive to the quark transversity distributions, which are currently poorly constrained by the experimental data, but could be significantly improved at the upcoming Electron-Ion Collider. Therefore, our work opens up a new avenue to utilize this new spin asymmetry for exploring the new physics effects from the scalar/tensor four-fermion operators.
↳ hep-phhep-exnucl-exnucl-thPRD(2024)·23 citations
26
Hot quark matter and merger remnants
Adamu Issifu🇧🇷 · Tobias Frederico🇧🇷
This work investigates hot quark matter under the thermodynamic conditions characteristic of a binary neutron star (BNS) merger remnants. We used the density-dependent quark mass model (DDQM) to access the microscopic nuclear equation of state (EoS) in a series of snapshots. The strange quark matter (SQM) is studied at finite temperature and entropy, in the presence of electrons and muons and their corresponding neutrinos to simulate the BNS merger conditions. For the first time, we introduced temperature into the DDQM model using a lattice QCD-motivated approach to construct both isentropic and isothermal EoSs. We observe that as the entropy of the SQM increases, the merger remnant becomes more massive and increases in size, whereas the neutrino abundance also increases. In the fixed-temperature case, on the other hand, we observe that the entropy spreads from the surface towards the center of the remnant. We determine the particle distribution in the core of the remnants, the structure of the remnant, the temperature profile, sound velocity, and the polytropic index, and discuss their effects. The strange-quark star (SQS) remnants satisfy the $2 M_{⊙}$ mass constraint associated with neutron stars (NS).
↳ hep-phnucl-thEPJA(2025)·4 citations

Affiliations

first authorsco-authorsvia INSPIRE