Nuclear Theory·nucl-th

Tuesday·October 28, 2025

22 papers—12 primary·10 cross-listed

01
Enhancement of Alpha Decay due to Medium Effects
Pankaj Jain🇮🇳 · Harishyam Kumar🇮🇳
We study the effect of medium on radioactive alpha decay and other similar decays. The initial state in these type of decays is a quasi-bound state with energy greater than zero. Such a state has very large amplitude in the nuclear region and is exponentially suppressed at larger distances. The decay rate of such states is known to decrease rapidly with decrease in the Q-value. Here we study such a decay within a medium. We assume a simple spherically symmetric repulsive potential model for the medium. This models the cumulative effect of all nuclei in the medium which at short distances present repulsive Coulomb interaction. We find that as the Q-value becomes very small, the medium effects lead to a substantial enhancement in rate. In contrast, for large Q-values, the medium effects are negligible. We briefly comment on application to real systems and the experimental implications of this result.
nucl-th0 citations
02
Pairing gap as a new observable for critical points in the region of A=100
Hossein Emami · Hadi Sabri
This study used the pairing gap to identify nuclei as candidates for critical point symmetry around Z=40 and A=100. Nuclei around A = 100 display complex shape evolution and configuration crossing patterns. We utilized the experimental and algebraic frameworks of the interacting boson model and the newly developed interacting boson-fermion model to study the isotopes of Mo and Ru. The results show significant variations in these quantities across nuclei located at the E(5) and X(5) critical points, analyzed through different observables. We also examined another region that is suitable for a shape phase transition. Furthermore, our findings suggest new candidates for critical points in other phase transitional regions for different isotopic chains.
nucl-thnucl-exMod.Phys.Lett.A(2026)·0 citations
03
Origin of the electric hexadecapole isomer in $^{93}$ Mo
B. Maheshwari🇫🇷 · P. Van Isacker🇫🇷 · P. M. Walker🇬🇧
We present a shell-model analysis of $^{93}$ Mo to investigate the unusual behavior of its $21/2^{+}$ isomer -- a prominent candidate for nuclear excitation by electronic capture. This state is unique as its decay is dominated by a slow electric hexadecapole $E 4$ transition, while the typically much faster electric quadrupole $E 2$ decay path is energetically forbidden. We investigate the microscopic origin of this phenomenon by examining in detail the structure of the wave functions of the initial and final states, and the $E 4$ transition matrix elements. This analysis of $^{93}$ Mo is contrasted with that of its particle-hole conjugate, $^{99}$ Cd, where such an $E 4$ transition is absent.
nucl-thnucl-exEPJ Web Conf.(2025)·0 citations
04
Investigation of evaluated nuclear data in the prediction of inherent neutron sources
Sigtryggur Hauksson · Ilaria Casalbore · Daniele Tomatis · Nunzio Burgio
Quantifying inherent neutron sources in matter, particularly $(α, n)$ reactions and spontaneous fission, is important in nuclear engineering and other fields. The SOURCES code is a common tool for calculating the yield and spectrum of such neutrons. This paper critically examines all modelling assumptions and nuclear data in SOURCES and proposes alternative approaches where applicable. For $(α, n)$ reactions, we show that the alpha emission lines for $^{235} U$ should be updated. Furthermore, we compare four different stopping power data sets for alpha particles slowing down and propose measurements to constrain mixed oxide nuclear fuel data. We use the computer code PHITS to show that energy and angular straggling during the slowing down of alpha particles in the material of interest is unimportant. Then, we compare the cross section and emission spectrum of $(α, n)$ reactions in SOURCES to recently evaluated data libraries. Importantly, the modelling of SOURCES for the emission spectrum seems too simple and may need to be updated. Finally, we compare data on spontaneous fission and show that while the neutron yield from SOURCES is reliable, some discrepancy is found with the neutron spectrum of evaluated data libraries. Complementing this work is an implementation of spontaneous fission in the Monte Carlo code OpenMC.
nucl-thEur.Phys.J.Plus(2025)·0 citations
05
An End-to-End Generative Diffusion Model for Heavy-Ion Collisions
Jing-An Sun🇨🇳 · Li Yan🇨🇳 · Charles Gale🇨🇦 · Sangyong Jeon🇨🇦
Heavy-ion collision physics has entered the high precision era, demanding theoretical models capable of generating huge statistics to compare with experimental data. However, traditional hybrid models, which combine hydrodynamics and hadronic transport, are computationally intensive, creating a significant bottleneck. In this work, we introduce DiffHIC, an end-to-end generative diffusion model, to emulate ultra-relativistic heavy-ion collisions. The model takes initial entropy density profiles and transport coefficients as input and directly generates two-dimensional final-state particle spectra. Our results demonstrate that DiffHIC achieves a computational speedup of approximately $1 0^{5}$ against traditional simulations, while accurately reproducing a wide range of physical observables, including integrated and differential anisotropic flow, multi-particle correlations, and momentum fluctuations. This framework provides a powerful and efficient tool for phenomenological studies in the high-precision era of heavy-ion physics.
nucl-thnucl-exEPJ Web Conf.(2026)·0 citations
06
Non-local orbital-free density functional theory incorporating nuclear shell effects
Xinhui Wu · Gianluca Colò · Kouichi Hagino · Pengwei Zhao
Incorporating nuclear shell effects within the framework of orbital-free density functional theory (DFT) has remained a longstanding challenge in nuclear physics. While the Hohenberg-Kohn theorem formally guarantees the existence of an orbital-free density functional that is capable of describing all many-body effects, including shell effects, practical attempts since the 1970s have consistently failed to capture such effects. This persistent difficulty has even led to the misconception that the orbital-free DFT is inherently unable to describe nuclear shell effects. Here we develop a {\it non-local} orbital-free DFT approach for atomic nuclei and demonstrate that nuclear shell effects can be successfully incorporated into the orbital-free DFT through the construction of a non-local kinetic energy density functional. In particular, we show that the non-local orbital-free functional yields a nucleon localization function that, as an established indicator of shell effects, exhibits consistent behavior with the exact Kohn-Sham solution.
nucl-thnucl-exPRL(2026)·5 citations
07
Nucleon-nucleon scattering up to next-to-leading order in manifestly Lorentz-invariant chiral effective field theory: low phases and the deuteron
Xiu-Lei Ren🇨🇳 · E. Epelbaum🇩🇪 · J. Gegelia🇩🇪
Recently the nucleon-nucleon interaction derived using time-ordered perturbation theory in manifestly Lorentz-invariant chiral effective field theory was shown to yield promising results for peripheral neutron-proton scattering. In this work we study low partial waves at next-to-leading order by treating the potential non-perturbatively in the scattering equation. Reasonable description of the phase shifts in the $S$ and $P$ waves as well as the deuteron properties is observed, which can be regarded as a feasibility study for the application of our formalism to the few- and many-body calculations.
nucl-thPRC(2026)·2 citations
08
Baryon and electric charge stoppings in nuclear collisions and the role of strangeness
Mason Alexander Ross🇺🇸 · Zi-Wei Lin🇺🇸
It has been challenging to quantitatively understand the stopping of incoming nucleons in nuclear collisions, and recently it has been proposed that comparing the baryon stopping with electric charge stopping can help address the question. Here we focus on the $B / Q \times Z / A$ ratio, which can strongly depend on rapidity although its value is one for the full phase space. We find that this ratio is very sensitive to the difference between strange and anti-strange rapidity distributions (the $s - s ˉ$ asymmetry), and slightly more anti-strange quarks at mid-rapidity would lead to a ratio well below one. This is the case for Zr+Zr and Ru+Ru isobar collisions at $200 A$ GeV from a multi-phase transport (AMPT) model. Without the $s - s ˉ$ asymmetry, the AMPT model would give a mid-rapidity $B / Q \times Z / A$ ratio at or above one. In addition, the AMPT model gives $B /Δ Q \times Δ Z / A < 1$ at mid-rapidity for isobar collisions at all centralities, which strongly contradicts the recent data from the STAR Collaboration. We further find that the $B /Δ Q \times Δ Z / A$ ratio is very sensitive to the net-light quark ( $u, d$ ) stoppings, but it is less sensitive to the $s - s ˉ$ asymmetry than the $B / Q \times Z / A$ ratio by a factor of 3.
nucl-thhep-phnucl-exEPJC(2026)·4 citations
09
Calculation of Particle Pair Correlation Functions with Classical Trajectory Approximation
Sheng Xiao🇨🇳 · Yijie Wang🇨🇳 · Zhigang Xiao🇨🇳
Femtoscopic interferometry is a powerful tool for probing the spatio-temporal evolution of emission sources in heavy-ion collisions. A major challenge in the field is formulating a self-consistent description of the source function, final-state interactions between the particle pair, and interactions inherent to the source itself. To address this, we have developed a novel Monte Carlo model for calculating two-particle correlation functions in a classical trajectory approximation (CTA-I). The model incorporates self-consistently the emission source of thermal equilibrium and three-body final state interactions. Application of the model shows satisfactory fit to experimental data, revealing that the correlation function is highly sensitive to the source's spatio-temporal extent. In contrast, the temperature parameter governing the emitted particles' energy spectra has a negligible influence. Our approach offers the potential to extract the spatio-temporal information from the emission source, thereby advancing the applicability of femtoscopic interferometry in the Fermi energy domain.
nucl-thnucl-ex0 citations
10
Ground-state properties of finite nuclei in relativistic Hartree-Bogoliubov theory with an improved quark mass density-dependent model
Renli Xu · Chen Wu · Jian Liu · Bin Hong · Jie Peng · Xiong Li · Ruxian Zhu · Zhizhen Zhao · Zhongzhou Ren
A relativistic Hartree-Bogoliubov (RHB) model based on quark-meson coupling is developed, with a new parametrization derived from experimental observables. Using this model, we systematically investigate the ground-state properties of even-even nuclei spanning $8 \leq Z \leq 118$ , including binding energies, quadrupole deformations, root-mean-square (rms) charge radii, two-nucleon separation energies, two-nucleon shell gaps, and $α$ -decay energies. Comparisons with available experimental data demonstrate that this subnucleon-based RHB model reliably describes the ground-state properties of finite nuclei.
nucl-thCPC(2026)·0 citations
11
Multi-strange and charmed hadrons: A novel probe for the QCD equation of state at high baryon densities
Jan Steinheimer🇩🇪 · Tom Reichert🇩🇪 · Marcus Bleicher🇩🇪
Nuclear experiments near and below the threshold of hyperon production have shown that the production of Kaons is a sensitive probe for the dense QCD equation of state. At beam energies up to 1.5AGeV, strangeness production can probe the equation of state for densities up to approximately twice nuclear saturation. In this paper we will discuss the possibilities of extending this range in density by the study of multi-strange baryons as well as charmed hadrons in the SIS100 beam energy range up to $10 A$ GeV. Here, densities up to five times nuclear saturation can be reached and the production of multi-strange and charmed hadrons shows a strong sensitivity to the equation of state. On the other hand a precise prediction of the effect of the equation of state will require knowledge of the fundamental production cross section near the elementary production threshold in p+p collisions which is yet not measured for the hadrons discussed.
nucl-thhep-phEur.Phys.J.ST(2026)·4 citations
12
Observable Signatures of a Quarkyonic Phase in Neutron Stars
Probit J Kalita🇮🇳 · Tuhin Malik🇵🇹 · Tianqi Zhao🇺🇸 · Bharat Kumar🇮🇳 · James M. Lattimer🇺🇸
Quarkyonic matter in $\beta$-equilibrium is a potential description of cold dense matter in neutron stars (NSs), that introduces non-interacting quarks alongside nucleons and leptons in NS cores. In this paper, we impose observational and theoretical constraints on the model to perform Bayesian inference on it, and find that it is possible to have quarkyonic matter equations of state that satisfy all current astrophysical observations, thereby reinforcing the argument for its use alongside traditional ones. To differentiate between NSs where a quarkyonic phase does and does not appear in the core, we identify some novel signatures based on the mass-radius relation. Focusing on canonical ($1.4\ \mathrm{M_\odot}$) NSs, we find the populations of NSs with and without quarkyonic cores show separability on the basis of the slope and curvatures of the mass-radius curve, the central sound speed of the star, and the radius difference between two NSs of $2\ \mathrm{M_\odot}$ and $1.4\ \mathrm{M_\odot}$. Our results indicate that observing a neutron star with these signatures matching the values for quarkyonic core NSs would provide a strong evidence for the existence of a quarkyonic phase or a similar crossover transition in its core.
nucl-thastro-ph.HEgr-qc7 citations
13
QCD in strong magnetic fields: fluctuations of conserved charges and EoS
Heng-Tong Ding🇨🇳 · Jin-Biao Gu🇨🇳 · Arpith Kumar🇨🇳 · Sheng-Tai Li🇨🇳
Strong magnetic fields can profoundly affect the equilibrium properties, characterized by the equation of state and bulk thermodynamics of strongly interacting matter. Although such fields are expected in off-central heavy-ion collisions, directly measuring their experimental imprints remains extremely challenging. To address this, we propose the baryon-electric charge correlations $χ_{11}^{BQ}$ and the chemical potential ratio $μ_{Q} / μ_{B}$ as magnetic-field-sensitive probes, based on (2+1)-flavor QCD lattice simulations at physical pion masses. Along the transition line, $χ_{11}^{BQ}$ and $(μ_{Q} / μ_{B})_{LO}$ in Pb-Pb collisions increase by factors of 2.1 and 2.4 at $e B ≃ 8 M_{π}^{2}$ , respectively. To bridge theoretical predictions and experimental observations, we construct HRG-based proxies and apply systematic kinematic cuts to emulate STAR and ALICE detector acceptances. Furthermore, we extend this investigation to the QCD equation of state, and examine the leading-order thermodynamic coefficients for strangeness-neutral scenarios up to $e B ≃ 0.8 GeV^{2} \sim 45 m_{π}^{2}$ , revealing intriguing non-monotonic structures.
↳ hep-lathep-phnucl-exnucl-thJ.Subatomic Part.Cosmol.(2026)·3 citations
14
First non-zero measurement of a nuclear electric dipole moment
Gary Prézeau🇧🇷
This paper reports the first non-zero measurement of a nuclear electric dipole moment using a novel method based on the rate of change of a supercurrent first proposed in 2016~\cite{https://doi.org/10.48550/arxiv.1604.02152} and fleshed out in this current paper. The theory, experimental concept and implementation are described in detail. The non-zero nuclear electric dipole moment measured with over 1000 hours of data was that of $^{181}$ Ta producing a best value $∣ d_{e}^{Ta} ∣ = (3.39 \pm 0.3 1_{stat}) \cdot 1 0^{- 32} e \cdot cm$ and $∣ d_{e}^{Ta} ∣ = (3.39 \pm 3.18) \cdot 1 0^{- 32} e \cdot cm > 0$ at 99.985\%CL. There is an uncertainty on the value of overall multiplicative parameters such as the self-inductance of the superconducting circuit ( $\pm 4%$ ), the mutual inductance between the SQUID pickup coil and the sample wire ( $\pm 15%$ ), and the magnitude of the solenoid current ( $\pm 5%$ ). An upper-limit was estimated for the control element, $^{207}$ Pb, $∣ d_{e}^{Pb} ∣ ≲ 1.2 \cdot 1 0^{- 31} e \cdot cm$ at 95\%CL.
↳ nucl-excond-mat.supr-conhep-phnucl-th+10 citations
15
Interactions of Neutrino Wave Packets
Michael J. Cervia🇺🇸
The low energy effective field theory of interacting neutrinos derived from the Standard Model may be framed as a pointlike interaction and thereby modeled on a lattice of neutrino momenta. We identify a path to take a continuum limit of this lattice problem in the center of momentum frame. In this limit, the weak interaction is found to become trivial between incoming plane waves describing ultrarelativistic particles, unless finite neutrino wave packet sizes are taken into consideration. We follow up with an analytic treatment of interacting neutrino wave packets, demonstrating the importance of the wave packet size for characterizing neutrino-neutrino scattering in dense environments.
↳ hep-phhep-thnucl-thPRD(2026)·6 citations
16
Heavy-Flavor Fragmentation and Jet Structure from HF-NRevo: Bridging to Heavy-Ion Collisions
Francesco Giovanni Celiberto🇪🇸 · Francesca Lonigro🇪🇸
We present recent progress on the Heavy-Flavor Non-Relativistic Evolution (HF-NRevo) framework, designed to describe leading-power fragmentation of heavy-flavored hadrons at moderate to large transverse momentum. Starting from NLO NRQCD calculations for all partonic channels into pseudoscalar quarkonia, we construct the NRFF1.0 collinear fragmentation functions via DGLAP evolution in a variable-flavor number scheme. We outline future prospects in the heavy-ion context, where HF-NRevo can serve as a baseline for modeling in-medium modifications of heavy-flavor fragmentation in nuclear collisions. Its accurate modeling of the partonic hierarchy and threshold effects makes it ideally suited to explore jet-quenching sensitivity, energy-loss mechanisms, and the emergence of medium-modified fragmentation functions in the quark-gluon plasma. Moreover, it provides a natural baseline for implementing in-medium hadronization scenarios, including quarkonium regeneration and fragmentation-function apparent-shape distortion. These developments provide new handles for exploring heavy-flavor dynamics at the HL-LHC and future collider facilities.
↳ hep-phhep-exhep-thnucl-ex+1PoS(2026)·9 citations
17
Emergent spin polarization from $ρ$ meson condensation in rotating hadronic matter
Kshitish Kumar Pradhan🇮🇳 · Dushmanta Sahu🇲🇽 · Raghunath Sahoo🇮🇳
The behavior of vector mesons in extreme environments provides a unique probe of non-perturbative Quantum Chromodynamics. We investigate the conditions for Bose-Einstein condensation (BEC) of spin-1 $ρ$ mesons in dense rotating hadronic matter, a regime relevant to the peripheral heavy-ion collisions and the interiors of rapidly rotating neutron stars. When the $ρ$ meson chemical potential ( $μ_{ρ}$ ) approaches its effective mass ( $m_{ρ}^{*}$ ), a phase transition to BEC occurs. We demonstrate that this transition is non-trivially influenced by global rotation, which couples to the spin of the $ρ$ mesons, leading to a macroscopic spin alignment of the condensate along the axis of rotation. This interplay between condensation and rotation results in distinct polarization patterns, which can serve as a possible signature of a BEC in experiments. The results suggest that rapidly rotating neutron stars may harbor an anisotropic, spin-polarized $ρ$ -condensed phase, which could impact their equation of state.
↳ hep-phhep-exhep-thnucl-ex+1PLB(2026)·3 citations
18
Analytic $G_{0} W_{0}$ gradients based on a double-similarity transformation equation-of-motion coupled-cluster treatment
Marios-Petros Kitsaras · Johannes Tölle · Pierre-François Loos
The accurate prediction of ionization potentials (IPs) is central to understanding molecular reactivity, redox behavior, and spectroscopic properties. While vertical IPs can be accessed directly from electronic excitations at fixed nuclear geometries, the computation of adiabatic IPs requires nuclear gradients of the ionized states, posing a major theoretical and computational challenge, especially within correlated frameworks. Among the most promising approaches for IP calculations is the many-body Green's function $G W$ method, which provides a balanced compromise between accuracy and computational efficiency. Furthermore, it is applicable to both finite and extended systems. Recent work has established formal connections between $G W$ and coupled-cluster doubles (CCD) theory, leading to the first derivation of analytic $G W$ nuclear gradients via a unitary CCD framework. In this work, we present an alternative, fully analytic formulation of $G W$ nuclear gradients based on a modified version of the traditional equation-of-motion CCD formalism, enabling the inclusion of missing correlation effects in the traditional CCD methods.
↳ physics.chem-phcond-mat.mtrl-scicond-mat.str-elnucl-thJ.Chem.Phys.(2026)·1 citation
19
Determination of the Muon Lifetime in $^{76}$ Se with the MONUMENT experiment
G. R. Araujo🇨🇭 · D. Bajpai🇺🇸 · L. Baudis🇨🇭 · V. Belov🇷🇺 · E. Bossio🇩🇪 · T.E. Cocolios🇧🇪 · H. Ejiri🇯🇵 · M. Fomina🇷🇺 · K. Gusev🇷🇺 · I.H. Hashim🇲🇾 · M. Heines🇧🇪 · S. Kazartsev🇷🇺 and 17 other authors
Ordinary muon capture provides a benchmark for the nuclear physics models of neutrinoless double beta decay under comparable momentum transfer conditions. The total capture strength defines the lifetime of the muonic atom. The muon lifetime in $^{76}$ Se, the daughter nucleus of $^{76}$ Ge, was determined with improved accuracy by the MONUMENT collaboration, using an array of high-purity germanium detectors and a set of scintillator counters at the $π$ E1 muon beam line of the Paul Scherrer Institute. The new value of (135.1 $\pm$ 0.5) ns agrees with phenomenological calculations based on the quasiparticle random phase approximation with unquenched axial-vector coupling.
↳ nucl-exnucl-thPRC(2026)·0 citations
20
Pentaquarks on the light front, and their mixture with baryons
Nicholas Miesch🇺🇸 · Edward Shuryak🇺🇸 · Ismail Zahed🇺🇸
In previous papers we developed the light front formulation for Hamiltonians and wave functions (WFs) for mesons and baryons, with both confinement and chiral symmetry breaking. For baryons limited to the lowest Fock component with three quarks, the longitudinal WF is valued in an equilateral triangle with momentum fractions $x_{i}, i = 1, 2, 3$ . The WF was developed both numerically and using a basis function that diagonalizes the Laplacian with Dirichlet boundary conditions. In this paper we extend this analysis to $n$ quark states, and specialize to pentaquarks ( $n = 5$ ). We determine their masses and WFs, and address the mixing between baryons and pentaquarks, the issue central to understanding the observed antiquark sea of baryons.
↳ hep-phnucl-thPRD(2026)·3 citations
21
Anti-Flatness and Non-Local Non-stabilizerness in Two-Particle Scattering Processes
C. E. P. Robin · M. J. Savage
Non-local non-stabilizerness and anti-flatness provide a measure of the quantum complexity in the wavefunction of a physical system. Supported by entanglement, they cannot be removed by local unitary operations, thus providing basis-independent measures, and sufficiently large values underpin the need for quantum computers in order to perform precise simulations of the system at scale. Towards a better understanding of the quantum-complexity generation by fundamental interactions, the building blocks of many-body systems, we consider non-local non-stabilizerness and anti-flatness in two-particle scattering processes, specifically focusing on low-energy nucleon-nucleon scattering and high-energy Moller scattering. We find that the non-local non-stabilizerness induced in both interactions is four times the anti-flatness (which is found to be true for any two-qubit wavefunction), and verify the relation between the Clifford-averaged anti-flatness and total non-stabilizerness. For these processes, the anti-flatness is a more experimentally accessible quantity as it can be determined from one of the final-state particles, and does not require spin correlations. While the MOLLER experiment at the Thomas Jefferson National Accelerator Facility does not include final-state spin measurements, the results presented here may add motivation to consider their future inclusion.
↳ quant-phhep-phnucl-thPhys. Rev. D 114, 014007 (2026)·20 citations
22
Model-independent mass determination of near-threshold states from short-range production
Yong-Hui Lin🇩🇪 · Hans-Werner Hammer🇩🇪 · Ulf-G. Meißner🇩🇪
We propose a novel observable for the precision measurements of a wide class of near-threshold dimer states: the short-range production rate of a dimer--spectator two-body system, composed of the given near-threshold state and one of its constituents. Within the framework of nonrelativistic effective field theory, these production rates exhibit characteristic line shapes for the specific partial wave and reach a model-independent minimum. This feature enables a precise extraction of their masses from experimental data, provided that the line shape can be resolved with sufficient accuracy. Applying this novel method to both the $T_{b b ˉ 1} (10610) B$ and $T_{b b ˉ 1} (10650) B^{*}$ systems allows for a precise determination of the binding energy $δ$ of the $T_{b b ˉ 1} (10610)$ and $T_{b b ˉ 1} (10650)$ via the relation of $δ = - E_{dip}^{exp} / 0.1983$ once the respective dip position $E_{dip}^{exp}$ is experimentally identified.
↳ hep-phhep-exnucl-thPLB(2026)·2 citations

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