Nuclear Theory·nucl-th

Thursday·February 27, 2025

16 papers—6 primary·10 cross-listed

01
Quantum Monte Carlo Calculations of neutron- $α$ Scattering via an Integral Relation
Abraham R. Flores · Kenneth M. Nollett · Maria Piarulli
Nuclear physics seeks to describe both bound and unbound states within a unified predictive framework. While coordinate-space Quantum Monte Carlo (QMC) methods have successfully computed bound states for systems with $A \leq 12$ , their application to unbound states remains limited. In this work, we extend the QMC approach to enable a broader range of unbound-state calculations. Our method infers long-range amplitudes in the wave function from integrals over the short-range interaction region. By evaluating these integrals using Green's Function Monte Carlo wave functions with the Argonne $v_{18}$ potential, we accurately reproduce existing results for neutron-alpha scattering. This approach provides a systematic pathway for studying more complex nuclear systems, including coupled-channel scattering and the effects of three-nucleon forces. It serves as a powerful tool for advancing $ab initio$ calculations in nuclear reactions, paving the way for a unified framework that consistently describes both bound and scattering states within a single theoretical approach.
nucl-thPRC(2025)·7 citations
02
Ab Initio Calculations of the Carbon and Oxygen Isotopes: Energies, Correlations, and Superfluid Pairing
Young-Ho Song · Myungkuk Kim · Youngman Kim · Kihyeon Cho · Serdar Elhatisari · Dean Lee · Yuan-Zhuo Ma · Ulf-G. Meißner
We perform \textit{ab initio} nuclear lattice calculations of the neutron-rich carbon and oxygen isotopes using high-fidelity chiral interactions. We find good agreement with the observed binding energies and compute correlations associated with each two-nucleon interaction channel. For the isospin $T = 1$ channels, we show that the dependence on $T_{z}$ provides a measure of the correlations among the extra neutrons in the neutron-rich nuclei. For the spin-singlet S-wave channel, we observe that any paired neutron interacts with the nuclear core as well as its neutron pair partner, while any unpaired neutron interacts primarily with only the nuclear core. For the other partial waves, the correlations among the extra neutrons grow more slowly and smoothly with the number of neutrons. These general patterns are observed in both the carbon and oxygen isotopes and may be universal features that appear in many neutron-rich nuclei.
nucl-thhep-phnucl-exPLB(2026)·8 citations
03
Forbidden non-unique $β^{-}$ transitions and $g_{A}$ -sensitive electron spectral-shapes
Archana Saxena · Praveen C. Srivastava
In the present work, we have done a systematic study of beta decay properties such as electron spectral-shapes, shape factors, and log $f t$ values for the higher forbidden non-unique $β^{-}$ transitions in the mass region A=85-123. We have performed the nuclear shell model (SM) calculations to explore the sensitivity of the electron spectral-shapes for different axial-vector coupling constants $g_{A} = 0.8 - 1.27$ . The effective interactions GWBXG, G-matrix, SNET and SN100PN are used for different model spaces. In the present work, we have computed the electron spectral-shapes of $^{85}$ Br, $^{87}$ Rb, $^{93}$ Zr, $^{97}$ Zr, $^{101}$ Mo, $^{115}$ Cd, $^{117}$ Cd, $^{119}$ In, $^{123}$ Sn and $^{135}$ Cs by constraining the small relativistic nuclear matrix element from conserved vector-current hypothesis (CVC). We have found that the electron spectral-shapes are strongly dependent on $g_{A}$ except the second forbidden non-unique $β^{-}$ transition $^{93}$ Zr.
nucl-thnucl-exPRC(2025)·0 citations
04
Deuteron-Deuteron Interaction and Correlation Function
Duo-Lun Ge🇨🇳 · Zhi-Wei Liu🇨🇳 · Jun-Xu Lu🇨🇳 · Li-Sheng Geng🇨🇳
The interaction between deuterons ( $d$ - $d$ ) is pivotal for understanding the characteristics of certain light nuclei from the perspective of the deuteron cluster and achieving a precise reproduction of $d$ - $d$ fusion cross sections. In this work, we construct a new set of elastic $d$ - $d$ interactions by fitting the phase shifts using potentials parameterized in a Woods-Saxon shape. Then, the correlation functions are calculated with the obtained potential and compared with the recent measurements by the STAR collaboration. We find that the $d$ - $d$ phase shifts and the correlation functions are internally consistent, confirming that correlation functions can provide cross-check for the $d$ - $d$ interaction. In addition, both the $^{1} S_{0}$ bound state and the repulsive $^{5} S_{2}$ interaction contribute to the observed suppression in the measured correlation function. Moreover, we demonstrate that the $P$ -wave contribution of the correlation functions cannot be neglected, especially in determining the source size.
nucl-thPRC(2025)·13 citations
05
Rescattering effects on spin-interference for $ρ^{0}$ photoproduction in heavy-ion collisions
Yusong Wang🇨🇳 · Xinbai Li🇨🇳 · Ziyang Li🇨🇳 · Zebo Tang🇨🇳 · Xin Wu🇨🇳 · Wangmei Zha🇨🇳
Recent measurements by various experiments in ultra-peripheral collisions have observed spin-interference in $ρ^{0}$ photoproduction, marking a breakthrough in Fermi-scale quantum interference experiments. Building on this, STAR extended the measurement to hadronic heavy-ion collisions, where significant rescattering effects on $ρ^{0}$ mesons were expected. In this study, we investigate how these rescattering effects influence the measurement of spin-interference. By embedding $ρ^{0}$ mesons produced via photoproduction, modeled by the Vector Meson Dominance model, into the Ultrarelativistic Quantum Molecular Dynamics framework, we estimate the impact on the $cos 2 ϕ$ and $cos 4 ϕ$ modulations, where $ϕ$ is the angle between $ρ^{0}$ and one of the daughters' ( $π^{\pm}$ ) transverse momentum. The results indicate a significant suppression of the $cos 2 ϕ$ modulation, while the $cos 4 ϕ$ modulation remains largely unaffected, which provides insight for understanding the difference due to rescattering effects between experimental measurements and theoretical predictions for $ρ^{0}$ photoproduction in heavy-ion collisions.
nucl-thhep-exnucl-exPRC(2025)·0 citations
06
Firewall boundaries and mixed phases of rotating quark matter in linear sigma model
Sergio Morales-Tejera🇷🇴 · Victor E. Ambruş🇷🇴 · Maxim N. Chernodub🇷🇴
A rigidly-rotating body in unbounded space is usually considered a pathological system since it leads to faster-than-light velocities and associated breaches of causality. However, numerical results on chiral symmetry breaking in rotating plasmas of interacting fermions reveal surprisingly close correspondence in predictions between the rigorous bounded and formal unbounded approaches. To provide insight into this correlation, we consider the linear sigma model coupled to quarks, undergoing rigid rotation in unbounded Minkowski space-time. Within the mean-field approach, we adopt three consecutive levels of approximation to the ground state of the system that feature uniform (model 1), weakly inhomogeneous (model 2) and fully inhomogeneous (model 3) condensates. Models 1 and 2 that do not take into account spatial gradients of the condensate show agreement with the Tolman-Ehrenfest law. Model 3 exhibits a deviation from the Tolman-Ehrenfest prediction due to the appearance of a new energy scale set by the inhomogeneity of the ground state. Its boundary conditions are fixed by imposing regularity at the rotation axis and by demanding the global minimization of the grand potential. We dub the latter as ``firewall boundary conditions,'' translating into the requirement of vanishing condensate on the light cylinder, which follows from the fact that the system state formally diverges at the light cylinder. In all models, we present the phase diagram of the system and point out that in models 2 and 3, the system resides either in a chirally-restored phase, or in a mixed phase that possesses spatially-separated chirally-restored and chirally-broken phases. Finally, we discuss the properties of the system under inhomogeneous rotation using the relativistic version of the Rankine vortex model.
nucl-thhep-thPRD(2025)·9 citations
07
Quarkonium Polarization Kinetic Equation from Open Quantum Systems and Effective Field Theories
Di-Lun Yang · Xiaojun Yao
Recent measurements of polarization phenomena in relativistic heavy ion collisions have aroused a great interest in understanding dynamical spin evolution of the QCD matter. In particular, the spin alignment signature of $J / ψ$ has been recently observed in Pb-Pb collisions at LHC, which may infer nontrivial spin transport of quarkonia in quark gluon plasmas. Motivated by this, we study the spin-dependent in-medium dynamics of quarkonia by using the potential nonrelativistic QCD (pNRQCD) and the open quantum system framework. By applying the Markovian approximation and Wigner transformation, we systematically derive the Boltzmann transport equation for vector quarkonia with polarization dependence in the quantum optical limit. As opposed to the previous study for the spin-independent case where the collision terms depend on chromoelectric correlators, the new kinetic equation incorporates gauge invariant correlators of chromomagnetic fields that determine the recombination and dissociation terms with polarization dependence at the order we are working in the multipole expansion. In the quantum Brownian motion limit, the Lindblad equation with new transport coefficients defined in terms of the chromomagnetic field correlators have also been derived. Our formalism is generic and valid for both weakly-coupled and strongly-coupled quark gluon plasmas. It may be further applied to study spin alignment of vector quarkonia in heavy ion collisions.
↳ hep-phnucl-thPoS(2025)·0 citations
08
Implications of {\sigma}-cut potential on Antikaon condensates in neutron stars
Prashant Thakur🇮🇳 · Yashmitha Kumaran🇲🇽 · Lakshana Sudarsan🇬🇧 · Krishna Kunnampully🇬🇧 · B. K. Sharma🇮🇳 · T. K. Jha🇮🇳
We investigate the properties of neutron stars with antikaon condensation in the framework of the Relativistic Mean-Field (RMF) model with a $σ$ -cut potential. The well-known RMF models, TM1 and TM1e, are used to analyze the structure and composition of neutron stars. The antikaon condensation part of the equation of state (EoS) is constrained from the experimental data of K $^{-}$ atomic and kaon-nucleon scattering. The $σ$ -cut potential, which is known to make the EoS stiffer at high densities, is modulated by a free parameter $f_{s}$ . Our present analysis suggests that one can obtain neutron star configurations heavier than 2 $M_{⊙}$ with antikaon condensates in most cases for $f_{s}$ = 0.6. The antikaon phase transition is a second-order for $f_{s}$ = 0.6 for both TM1 and TM1e parameter sets. The calculated global properties of neutron stars with antikaon condensates i.e., mass and radius seem to be in resonable agreement with other theoretical and observational data.
↳ astro-ph.HEgr-qchep-phnucl-thPRC(2025)·6 citations
09
A hybrid model for multi-particle production and multi-fragment emission in electron-nucleus collisions at the forthcoming Electron-Ion Collider
Ting-Ting Duan🇨🇳 · Sahanaa Büriechin🇨🇳 · Hai-Ling Lao🇨🇳 · Fu-Hu Liu🇨🇳 · Khusniddin K. Olimov🇺🇿
To present a prediction of the multi-particle production and multi-fragment emission in electron-nucleus ( $e A$ ) collisions at the forthcoming Electron-Ion Collider (EIC), a simple hybrid model which is based on the multi-source thermal model and the ideal gas model is proposed in this article. According to the hybrid model, some statistical laws such as the two-component Erlang distribution and others are presented, which means a two-source production. These statistical laws are hopeful to describe the bulk properties of multiple particles produced in the scattering of electron-nucleon ( $e N$ ) and multiple fragments emitted in the fragmentation of excited residual nucleus. Although both the scattering and fragmentation can occur in $e A$ collisions at the EIC, their two-sources are different. In $e N$ scattering, the multiple particles come from the soft excitation and hard scattering processes respectively, which are classified as two different types of events. In nuclear fragmentation, the multiple fragments come from the cold and hot sources which exist in the same excited nucleus.
↳ hep-phhep-exnucl-exnucl-thMod.Phys.Lett.A(2025)·0 citations
10
Proper effective temperature and order parameters in relativistic non-equilibrium steady states
Shin Nakamura🇯🇵 · Fuminori Okabayashi🇯🇵
We examine the concept of temperature in non-equilibrium steady states. Using the D3-D5 model of gauge/gravity duality, we investigate spontaneous symmetry breaking in a relativistic (2+1)-dimensional defect moving at constant velocity within a (3+1)-dimensional heat bath. We find that the dependence of the order parameter on both the heat bath temperature and the defect velocity can be captured by a single variable -- the proper effective temperature -- for the moving defect. Our results suggest that the proper effective temperature is an essential parameter for a class of relativistic non-equilibrium steady states.
↳ hep-thcond-mat.stat-mechnucl-thJHEP(2025)·2 citations
11
Chiral Representation of the Nucleon Mass at Leading Two-loop Order
Ze-Rui Liang🇨🇳 · Han-Xue Chen🇨🇳 · Feng-Kun Guo🇨🇳 · Zhi-Hui Guo🇨🇳 · De-Liang Yao🇨🇳
We calculate the nucleon mass in a manifestly relativistic baryon chiral perturbation theory up to the leading two-loop order. Through dimensional counting analysis, we perform the chiral expansion and verify the validity of the extended-on-mass-shell scheme at the two-loop level. As a result, we obtain the complete chiral representation of the nucleon mass up to $O (p^{5})$ , which preserves the original analytic properties and satisfies the correct power counting. The obtained chiral result is well-suited for chiral extrapolation and provides an excellent description of lattice QCD data across a broad range of pion masses. We find that the $O (p^{5})$ contribution is small, approximately $10$ MeV, and varies only mildly with increasing pion mass, demonstrating good convergence of the nucleon mass up to pion masses of about 350 MeV at two-loop order.
↳ hep-phhep-latnucl-thJHEP(2025)·8 citations
12
Higher derivative holography and temperature dependence of QGP viscosities
Thomas Apostolidis🇫🇷 · Umut Gürsoy🇳🇱 · Edwan Préau🇳🇱
Recent Bayesian analyses of heavy ion collision data have established a non-trivial temperature dependence of the shear and bulk viscosity per entropy. Motivated by this, we consider higher derivative corrections to realistic, bottom-up holographic models of quark-gluon plasma based on five-dimensional Einstein-dilaton theories and determine the dilaton potentials in the higher derivative terms by matching the Bayesian analyses. A byproduct of our analysis is the bulk viscosity that follows from the holographic V-QCD theory. Higher derivative corrections when treated perturbatively lead to tension with existing data. We investigate possible resolutions.
↳ hep-thhep-exhep-phnucl-thJHEP(2025)·4 citations
13
Chiral vortical conductivities and the moment of inertia of a rigidly rotating Fermi gas
M. Abedlou Ahadi🇮🇷 · N. Sadooghi🇮🇷
We determine the chiral vortical conductivities, as well as the orbital and spin moment of inertia of a charged, chiral, and rigidly rotating free Fermi gas. To this purpose, we begin by calculating the vacuum expectation values of a vector and axial vector current using the free fermion propagator in this medium. This propagator is derived by employing the Fock-Schwinger method based on the solutions of the Dirac equation in the presence of rotation and finite axial chemical potential. We present a complete derivation of these solutions. We demonstrate that in the first approximation, the chiral vortical conductivity associated with the vector current is proportional to the product of the vector and axial chemical potentials. In contrast, the chiral vortical conductivity related to the axial vector current depends on the temperature, the vector, and the axial vector chemical potential squares. We use the relation between the axial vector current and the angular momentum density associated with spin to determine the spin and the orbital moment of inertia of a rigidly rotating Fermi gas in a charged and chirally imbalanced medium separately. In addition, we compute the total moment of inertia by utilizing the methods presented in the first part of the paper and show that the orbital moment of inertia of a free fermion gas vanishes.
↳ hep-phcond-mat.quant-gasnucl-thPRD(2025)·5 citations
14
Topological Susceptibility in the Superconductive Phases of Quantum Chromodynamics: a Dyson-Schwinger Perspective
Fabrizio Murgana🇮🇹 · Giorgio Comitini🇮🇹 · Marco Ruggieri🇮🇹
We test non-perturbative gluon propagators recently studied in the literature, by computing the topological susceptibility, $χ$ , of the superconductive phases of Quantum Chromodynamics at high density. We formulate the problem within the High-Density Effective Theory, and use the 2-particle irreducible formalism to compute the effective potential of the dense phases. We focus on superconductive phases with two and three massless flavors. Within this formalism, we write a Dyson-Schwinger equation in the rainbow approximation for the anomalous part of the quark propagator in the superconductive phases, in which the non-perturbative gluon propagator plays its role. We complete the model by adding a $U (1)_{A}$ -breaking term whose coupling is fixed perturbatively at large quark chemical potential. We then use the effective potential to compute $χ$ in the superconductive phases. We finally discuss implications of the results for the axion mass in superdense phases of Quantum Chromodynamics.
↳ hep-phhep-thnucl-thPRD(2025)·4 citations
15
Correlation function for the $p f_{1} (1285)$ interaction
Pablo Encarnación🇪🇸 · Albert Feijoo🇪🇸 · Eulogio Oset🇪🇸
We have addressed here the problem of calculating the correlation function of a stable particle with a resonance, in particular one resonance that qualifies as a molecular state of two components. The formalism used requires to evaluate the scattering matrix of the stable particle with the molecule, a nuclear problem which we address by means of the fixed center approximation. We have applied the method to the interaction of a proton with the $f_{1} (1285)$ resonance, presently under investigation by the ALICE collaboration, where the $f_{1} (1285)$ is taken as a $K^{*} K ˉ - K ˉ^{*} K$ molecule. We find that the $p f_{1} (1285)$ interaction develops a resonance state below the $p f_{1} (1285)$ threshold, which leads to a depletion in the $p f_{1} (1285)$ correlation function for small values of the proton momentum. The discussion presented shows that these type of studies can provide much information on the nature of some resonances and the existence of three-body bound states involving mesons and baryons.
↳ hep-phnucl-thPRD(2025)·13 citations
16
Work and heat exchanged during sudden quenches of strongly coupled quantum systems
Zohreh Davoudi · Christopher Jarzynski · Niklas Mueller · Greeshma Oruganti · Connor Powers · Nicole Yunger Halpern
How should one define thermodynamic quantities (internal energy, work, heat, etc.) for quantum systems coupled to their environments strongly? We examine three (classically equivalent) definitions of a quantum system's internal energy under strong-coupling conditions. Each internal-energy definition implies a definition of work and a definition of heat. Our study focuses on quenches, common processes in which the Hamiltonian changes abruptly. In these processes, the first law of thermodynamics holds for each set of definitions by construction. However, we prove that only two sets obey the second law. We illustrate our findings using a simple spin model. Our results guide studies of thermodynamic quantities in strongly coupled quantum systems.
↳ quant-phcond-mat.stat-mechhep-lathep-ph+1PRE(2026)·10 citations

Affiliations

first authorsco-authorsvia INSPIRE