Nuclear Theory·nucl-th

Tuesday·September 30, 2025

24 papers—14 primary·10 cross-listed

01
[Submitted on 26 Sept 2025]
Regularized Lednicky-Lyuboshitz formula for higher partial waves in femtoscopy
Koichi Murase · Tetsuo Hyodo
Femtoscopy is one of the promising experimental approaches to put constraints on interactions between various species of hadrons from the momentum correlation functions measured in high-energy nuclear collision experiments. The Koonin-Pratt and Lednicky-Lyuboshitz formulae provide useful expressions of the correlation functions and have been widely used to analyze the experimental data based on the assumption that the effect of higher partial waves is negligible. Those formulae can be generalized for higher partial waves, but the generalized Lednicky-Lyuboshitz formula produces wrong results due to a singular behavior of the asymptotic wave function at the origin. In this study, we attempt to solve the problem by regularizing the generalized Lednicky-Lyuboshitz formula with a cutoff and validate it using the Koonin-Pratt formula as a reference. We also show the relationship between the cutoff in the regularized Lednicky-Lyuboshitz and the effective-range correction in the original Lednicky-Lyuboshitz formula. Using the obtained formula, we investigate the source-size dependence, the validity of the effective range expansion, and the cutoff dependence of the correlation function. We also discuss the interaction dependence using the heatmap as a function of the scattering-length parameter $1/ a_{l}$ and the momentum $q$ .
Comments:
15 pages, 12 figures, 2 tables
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2509.22844 [pdf]
2 citations
02
[Submitted on 27 Sept 2025]
Exploring parameter dependence of heavy-flavor dynamics in small collision systems
Grace Pang🇺🇸
Observations from high-multiplicity proton-lead ( $p$ -Pb) collisions indicate that small systems may exhibit collective behavior in both heavy and light hadrons. This work investigates the roles of initial- and final-state interactions in shaping the nuclear modification factor and elliptic flow of $D$ mesons measured in $p$ -Pb collisions. Initial-state effects, including the Cronin and shadowing effects, are considered in the heavy-quark initial conditions, while final-state interactions are simulated through Langevin evolution combined with the coalescence model of hadronization. Different initial geometries attributed to fluctuations in the medium's energy density are parametrized and translated into the momentum anisotropies of both light and heavy quarks. The corresponding $R_{pP b}$ and $v_{2}$ of D mesons in 8.16 TeV $p$ -Pb collisions are calculated under different assumptions for the final-state interactions. Assuming that the initial-state effects only modify the transverse momentum spectra without altering the azimuthal distribution of heavy quarks, the measured $R_{pP b}$ of D mesons can be qualitatively reproduced by the combined influence of initial- and final-state effects. However, the observed $v_{2}$ cannot be accounted for by final-state interactions alone. These results suggest that additional contributions to azimuthal anisotropies of heavy quarks originating from initial-state effects are required to explain the experimentally observed $v_{2}$ .
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph)
arXiv:
2509.23081 [pdf]
PRC(2025)·0 citations
03
[Submitted on 27 Sept 2025]
Ab initio study of island of inversion in odd- $A$ nuclei: Structure of $^{31, 33}$ Mg
Subhrajit Sahoo · Praveen C. Srivastava
We study the $N = 20$ island of inversion region in the odd- $A$ Ne and Mg isotopes from the fundamental nuclear forces based on chiral two- and three-nucleon potentials. The state-of-the-art \textit{ab initio} valence space in medium similarity renormalization method was used for this purpose. Our study focuses on the evolution of single-particle states and discusses their transition into the island of inversion through particle-hole excitations across the $N = 20$ shell gap. The computed low-lying states and magnetic moments are in good agreement with the experimental data. We presented the rotational band structures, established via $E 2$ transitions, in $^{31}$ Mg and $^{33}$ Mg, which emerge from both normal and intruder configurations at low excitation energies. Our results suggest the presence of weak, moderate, and strongly prolate-deformed configurations at low energy in both isotopes. The present work offers valuable insights into the configurations and shapes of low-lying states in nuclei within the island of inversion, enhancing our understanding of the structures of exotic nuclei from first principles.
Comments:
10 pages, 9 figures
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2509.23354 [pdf]
PRC(2025)·5 citations
04
[Submitted on 28 Sept 2025]
Microscopic study of the asymptotic behavior of the reduced width amplitude in $^{7}$ Li and $^{7}$ Be
H. J. Zhu · M. J. Lyu · Q. Zhao · Z. Cheng · J. Q. Tian · M. Kimura · T. Myo · H. Horiuchi · H. Toki · M. Isaka · H. Takemoto · Akinobu Doté · N. Wan
We investigate the effects of different basis model spaces on the calculation of reduced width amplitude (RWA) and asymptotic normalization coefficient (ANC) for the $^{7}$ Li and $^{7}$ Be nuclei. The two-cluster model ( $α + t /^{3}$ He) and three-cluster model ( $α + d + n / p$ ) with the generator coordinates method (GCM) are applied to calculate the wave function of $^{7}$ Li and $^{7}$ Be. Specifically, the model space for the three-cluster model is constructed upon a sufficiently broad space of two-cluster configuration bases by further including three-cluster configuration bases. We compare the impact on the results from two basis sets for these added three-cluster bases: one with a compact and one with a broad spatial distribution. The final results reveal that the two-cluster model cannot accurately reproduce the binding energies of $^{7}$ Li and $^{7}$ Be, and tends to overestimate their ANCs. Regarding the calculations with the three-cluster model, while the two basis sets do not give significant differences in energy or energy spectrum, the basis set with a compact model space fails to describe the asymptotic behavior of the RWA adequately. This introduces excessive uncertainty into the ANC calculation. In the end, we conclude that when calculating ANC via a microscopic framework, particular attention must be paid to ensuring sufficient model space, especially for the components describing the breakup channels. This approach provides ANC values for $^{7}$ Li and $^{7}$ Be that agree well with experimental results.
Comments:
8 pages, 6 figures. Submitted to Physical Review C
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2509.23613 [pdf]
PRC(2026)·1 citation
05
[Submitted on 28 Sept 2025]
Regulator constraints for the perturbative renormalizability of attractive triplets
Manuel Pavon Valderrama🇨🇳
Nuclear effective field theory organizes the calculation of observables as a power series in terms of the ratio of soft and hard momentum scales. The rigorous implementation of this idea requires a mixture of perturbative and non-perturbative methods: on the one hand, nuclei are bound states that require the iteration of part of the nuclear potential, while on the other corrections that are small in the aforementioned power series should be perturbative in principle. Recently, it has been noted that these corrections are not cutoff independent as there are a set of exceptional cutoffs for which the couplings cannot be determined, as exemplified with the subleading order $^{3} P_{0}$ phase shifts in two-nucleon scattering. Yet, here it is shown by means of concrete calculations that exceptional cutoffs are a regulator-dependent feature. There exists a well-defined limit when the cutoff is removed, which implies that not every regulator choice (understood not only as the regulator itself, but in tandem with renormalization conditions) is acceptable within the effective field theory framework. The practical implications are minor, though: except if one is trying to explicitly probe the cutoff independence of the theory, most sensible regulator and cutoff choices are compatible with the renormalized limit within truncation errors.
Comments:
25 pages, 12 figures, corresponds to accepted version in PRC
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2509.23855 [pdf]
PRC(2025)·7 citations
06
[Submitted on 28 Sept 2025]
New ab initio constrained extended Skyrme equations of state for simulations of neutron stars, supernovae and binary mergers: II. Thermal response in the suprasaturation density domain
Adriana R. Raduta🇷🇴 · Mikhail V. Beznogov🇷🇴
Numerical simulations of core-collapse supernovae, mergers of binary neutron stars and formation of stellar black holes, which employed standard Skyrme interactions, established clear correlations between the evolution of these processes, characteristics of the hot compact objects, as well as neutrino and gravitational wave signals, and the value of effective nucleon mass at the saturation density. Unfortunately, the density dependence of the effective mass of nucleons in these models does not align with the predictions of ab initio models with three body forces. In this work, we investigate the thermal response for a set of extended Skyrme interactions that feature widely different density dependencies of the effective mass of the nucleons. Thermal contributions to the energy density and pressure are studied along with a few thermal coefficients over wide domains of density, temperature and isospin asymmetry, relevant for the physics of hot compact objects. For some of the effective interactions, the thermal pressure is negative at high densities. This results in a situation where hot compact stars can support less mass before collapsing into a black hole compared to their cold counterparts. Moreover, the higher the temperature, the lower the maximum mass that the hot star can support.
Comments:
12 pages, 13 figures
Subjects:
Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE)
arXiv:
2509.23910 [pdf]
Astron.Astrophys.(2026)·2 citations
07
[Submitted on 29 Sept 2025]
Properties of hyperons in nuclear matter from chiral hyperon-nucleon interactions at next-to-next-to-leading order
Asanosuke Jinno🇯🇵 · Johann Haidenbauer🇩🇪 · Ulf-G. Meißner🇨🇳
The $Λ$ and $Σ$ single-particle potentials in infinite nuclear matter are analyzed within a recently established chiral hyperon-nucleon ( $Y N$ ) interaction up to N $^{2}$ LO in combination with an nucleon-nucleon interaction derived in the same scheme. The self-consistent Brueckner-Hartree-Fock method with the continuous choice of the single-particle potential is employed. It is found that the $Λ$ single-particle potential is comparable to the results achieved with the NLO $Y N$ interaction from 2019. The resulting $Σ$ potential becomes more attractive compared to the previous NLO results due to the constraint from the recent $Σ N$ differential cross section data measured in the J-PARC E40 experiment. An estimate of the theoretical uncertainty of the single-particle potentials is provided in terms of the truncation error in the chiral expansion.
Comments:
21 pages, 14 figures, 6 tables, corrected typo, published by PRC
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2509.24459 [pdf]
PRC(2025)·4 citations
08
[Submitted on 29 Sept 2025]
Effective $β$ -decay rates of $r$ -process waiting points in realistic stellar environments
Qi-Ye Hu · Long-Jun Wang · Yang Sun
Reliable nuclear weak rates are key inputs for understanding the origin of heavy elements and constraining the environments of the corresponding stellar nucleosynthesis. We present the effective stellar $β^{-}$ -decay rates of the $N = 50, 82, 126$ $r$ -process waiting-point nuclei in realistic stellar environments with high temperature, high density and strong magnetic field. Both allowed and first-forbidden transitions are considered, and transitions from the low-lying states of parent nuclei due to the thermal population are taken into account properly. The stellar $β^{-}$ -decay rates of the $N = 50, 82$ waiting points are not sensitive to stellar temperature, while those of the $N = 126$ waiting points increase rapidly with stellar temperature. With the increase of stellar density, the electron chemical potential increases accordingly, which leads to reduction of the stellar $β$ -decay rates. Besides, the stellar $β$ -decay rates are found to increase rapidly with the magnetic field $B$ when $B ≳ 1 0^{14}$ G. Depending on the stellar temperature, density and magnetic field, the rates may vary by several orders of magnitude, which indicates that dynamic $β$ -decay rates for corresponding stellar conditions may be indispensable inputs for understanding the $r$ -process nucleosynthesis.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2509.24536 [pdf]
0 citations
09
[Submitted on 29 Sept 2025]
Many-body correlations as the origin of Gamow-Teller quenching in nuclear $β$ -decay
Hao Zhou · Long-Jun Wang · Yang Sun
The longstanding quenching problem of Gamow-Teller (GT) strength in nuclear $β$ -decay is attributed to missing contributions in the transition operator and/or incomplete nuclear correlations in the many-body wavefunction. Recent studies have predominantly emphasized operator renormalization, including chiral two-body currents, while the effects of many-body correlations--especially in heavy open-shell nuclei--remain underappreciated. We present a large-configuration shell-model calculation that incorporates chiral two-body weak current and treats both mechanisms on equal footing. Taking the neutrinoless double $β$ -decay candidate $^{76}$ Ge as an example, we demonstrate that strong nuclear correlations drive a substantial portion of GT strength to high excitation energies, leading to a pronounced suppression of low-energy strength responsible for the apparent quenching. We identify that the quenching originates mainly from deformation, cross-shell correlations, and mixing among densely-spaced highly excited states. In contrast, the chiral two-body current contributes only a modest $5 - 15%$ reduction, depending on the coupling constants employed. Our results thus suggest many-body correlations as the primary origin of GT quenching and provide a unified microscopic explanation for this phenomenon in nuclear $β$ -decay.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2509.24542 [pdf]
2 citations
10
[Submitted on 29 Sept 2025]
Anomaly in first-forbidden transitions of $^{176}$ Lu
Jing-Wen Ran · Long-Jun Wang
$^{176}$ Lu is the key nucleus for understanding the evolution of planetary bodies in the solar system, and the temperature and nucleosynthesis of the $s$ process, due to its very long terrestrial half-life $T_{1/2} \approx 3.7 \times 1 0^{10}$ years. The very long half-life is caused by two anomalous first-forbidden transitions from the $7^{-}$ state with extremely large comparative half-life log $f t \approx 19$ which have never been appeared in other cases of the existing nuclear databases. We analyze the underlying mechanism and reason for the anomaly in first-forbidden transitions of $^{176}$ Lu for the first time, which is based on the projected shell model. It is found that the possible $K$ -forbidden nature is indispensable for describing the two extremely weak first-forbidden transitions, and the transition strengths are very sensitive to the detailed configuration mixing and $K$ mixing in the nuclear wave functions. The half-life of the $7^{-}$ state is calculated to be $T_{1/2} \approx 1.95 \times 1 0^{10}$ years.
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2509.24549 [pdf]
PLB(2026)·0 citations
11
[Submitted on 29 Sept 2025]
Transport properties of nuclear matter from anomalous fission yields
Karl-Heinz Schmidt🇩🇪 · Christelle Schmitt🇫🇷 · Andreas Heinz🇸🇪
In nuclear fission, a heavy nucleus splits into two fragments, driven by the Coulomb repulsion between the positively charged protons. The fission process is governed by the potential energy and basic transport properties of nuclear matter like inertial mass and viscosity. Both inertia and viscosity induce a delay, the so-called relaxation time, in the response towards statistical equilibrium of the mass-asymmetry degree of freedom on the fission path. We show that the conditions in the mass-asymmetry degree of freedom near the second barrier are preserved for all systems at excitation energies above a certain threshold. Anomalies that were hitherto unexplained appear in the fission yields and total kinetic energies at lower energies for trajectories, which can reach scission only by quantum-mechanical tunneling through the potential beyond the second barrier. This indicates that the relaxation time in the mass-asymmetry degree of freedom for classically allowed trajectories is longer than the dynamical saddle-to-scission time. This finding is the central result of our work that provides novel information on the transport properties of nuclear matter. Possible scenarios that explain this finding are discussed. These are either a long oscillation time due to a large influence of inertia or a strong friction resulting from a large viscosity. The first option is in severe conflict with the widely used assumption that the role of collective inertia in fission dynamics is negligible, while both options contradict the widespread assumption of local statistical equilibrium in all collective degrees of freedom along the fission path.
Comments:
14 pages, 5 figures; Fig. 1 modified; added references; revised interpretation of the data
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2509.24590 [pdf]
0 citations
12
[Submitted on 29 Sept 2025]
Uncertainties with low-resolution nuclear forces
Tom Plies🇩🇪 · Matthias Heinz🇩🇪 · Achim Schwenk🇩🇪
Low-resolution nuclear Hamiltonians, obtained from chiral effective field theory (EFT) and softened using renormalization group techniques, have been very successful in nuclear structure theory. The associated EFT truncation uncertainty for these potentials is difficult to quantify. We use singular value decompositions of low-resolution nuclear forces to obtain an operator basis to study Hamiltonian uncertainties for these potentials. We perform Bayesian inference for the singular values and three-body low-energy constants, the free parameters of nuclear Hamiltonians in our framework, using likelihoods based on nucleon-nucleon phase shifts and triton observables to account for the EFT truncation uncertainties in these quantities. Validating our inference, we find good reproduction of input uncertainties for low-energy phase shifts and three-nucleon observables. On the other hand, uncertainties for higher-energy phase shifts are systematically underestimated, which we attribute to limitations of the singular value decomposition and neglected correlations between phase shifts at different energies. We propagate the resulting distribution of Hamiltonians forward to predictions for ground-state properties of $^{24, 28}$ O and $^{48}$ Ca, comparing against other state-of-the-art nuclear structure predictions. Our approach makes it possible to account for EFT uncertainties when using low-resolution potentials, which is important for many ongoing studies in exotic nuclei.
Comments:
20 pages, 13 figures, published version
Subjects:
Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
arXiv:
2509.24671 [pdf]
PRC(2026)·6 citations
13
[Submitted on 29 Sept 2025]
Tracing pT-differential radial flow from blast-wave analytics to quark coalescence
Jie Wan🇨🇳 · Chun-Zheng Wang🇨🇳 · Yu-Gang Ma🇨🇳 · Qi-Ye Shou🇨🇳
The observable $v_{0} (\pt)$ , which quantifies event-by-event fluctuations in the differential transverse-momentum spectrum, is proposed as a direct and penetrating probe of radial flow in heavy-ion collisions. Recent measurements at the LHC exhibit a clear mass ordering for pions, kaons and protons at low \pt and a baryon-meson splitting at intermediate \pt, resembling to the well-known features of elliptic flow ( $v_{2}$ ). In this letter, we first derive an analytic expression of $v_{0} (\pt)$ within a Blast-Wave framework incorporating fluctuations of freeze-out temperature and radial expansion velocity, which can naturally explains the experimentally observed mass ordering. The distinct dynamical origins of the mass ordering in $v_{0} (\pt)$ and $v_{2} (\pt)$ are discussed. Furthermore, using the AMPT model, we demonstrate that the baryon-meson splitting emerges spontaneously from the quark coalescence. This study provides deeper insight into the $v_{0} (\pt)$ observable and the collective dynamics of the QGP.
Comments:
6 pages, 6 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2509.24889 [pdf]
PRC(2026)·6 citations
14
[Submitted on 29 Sept 2025]
Precision calculation of $^{3}$ He $(α, γ)^{7}$ Be for solar physics
Ratna Khadka🇺🇸 · Ling Gan🇺🇸 · Renato Higa🇺🇸 · Gautam Rupak🇺🇸
We calculate the cross section for radiative capture $^{3}$ He $(α, γ)^{7}$ Be at next-to-next-to-leading order (NNLO). At this order of perturbation, momentum dependent two-body currents make their first appearance. We provide a model-independent construction of these currents from gauge and Galilean invariance, where the general framework for constructing higher-order two-body currents in low-energy effective field theories becomes evident. The $^{3}$ He $(α, γ)^{7}$ Be astrophysical S-factor $S_{34} (0) = 0.56 4_{- 0.015}^{+ 0.17}$ keV b is obtained from a Bayesian analysis at NNLO, with an additional nominal theoretical uncertainty $\pm 0.017$ keV b of 3%.
Comments:
Main text 8 pages with 3 figures and 3 tables, supplementary material 4 pages with 1 figure and 1 table
Subjects:
Nuclear Theory (nucl-th); Solar and Stellar Astrophysics (astro-ph.SR); Nuclear Experiment (nucl-ex)
arXiv:
2509.24931 [pdf]
PLB(2026)·1 citation

Affiliations

first authorsco-authorsvia INSPIRE