Nuclear Theory·nucl-th

Tuesday·May 19, 2026

21 papers—10 primary·11 cross-listed

11
3D Initial-State Dynamics across scales: A Comparative Study of saturation and string-based descriptions
Lucas Constantin🇩🇪 · Oscar Garcia-Montero🇪🇸 · Niklas Götz🇩🇪 · Hannah Elfner🇩🇪
We compare the longitudinal deposition of various conserved quantities in the initial condition models of a string based (SMASH) and a saturation based (McDipper) approach. SMASH has been shown to work reasonably well at lower collision energies as an initial condition for the SMASH-vHLLE hybrid approach, while McDipper, based on the color-glass-condensate (CGC), works well in the regime of perturbative QCD. The two models are capable of providing longitudinally resolved initial conditions, which is essential for 3D hydrodynamical simulations. The goal of this study is to interface the different regions of applicability of the two models, to investigate the initial state dynamics in the intermediate energy regime. We analyze the deposition of transverse energy, charge and baryon number across a large range of collision energies (62.4 GeV to 5.02 TeV) and find that, while they are good agreement at lower energies, their energy and baryon deposition differs substantially at higher center of mass energies.
↳ hep-phnucl-th1 citation
12
Nonlinear response of the chiral magnetic effect in the D3/D7 holographic model
Masataka Matsumoto🇯🇵 · Mirmani Mirjalali🇮🇷 · Ali Vahedi🇮🇷
We investigate the nonlinear response of the chiral magnetic current to an external magnetic field in a holographic setup. Using the D3/D7 brane system, where the chiral magnetic effect (CME) can be realized by considering rotating probe D7-branes, corresponding to introducing an axial chemical potential, we analyze the current-magnetic field relation beyond the linear regime. Focusing on the vicinity of the phase boundary between the insulating phase and the CME phase, we find that the chiral magnetic current exhibits a multi-valued dependence on the magnetic field, indicating a highly nonlinear response characteristic of this model. We further study the dynamical stability of the insulating phase near the transition point, and show that the presence of both an axial chemical potential and an external magnetic field cooperatively stabilize the system. Our results clarify the interplay between the axial chemical potential and the magnetic field in determining the phase structure and stability of the system, and reveal new nonlinear aspects of chiral transport in holographic gauge theories.
↳ hep-thcond-mat.str-elnucl-th0 citations
13
Two-nucleon systems at $m_{π} \approx 292$ MeV from lattice QCD
Kuan Zhang🇨🇳 · Kang Yu🇨🇳 · Yiqi Geng🇨🇳 · Chuan Liu🇨🇳 · Liuming Liu🇨🇳 · Peng Sun🇨🇳 · Jia-Jun Wu🇨🇳 · Ruilin Zhu🇨🇳
Nucleon-nucleon systems in the $^{3} S_{1}$ and the $^{1} S_{0}$ channels are studied in lattice quantum chromodynamics at a pion mass of approximately $m_{π} \approx 292$ MeV, employing three $N_{f} = 2 + 1$ ensembles with the same pion mass and lattice spacing $a = 0.10530 (18)$ fm but different spatial volumes. Finite-volume energies of the nucleon-nucleon systems are determined in both the rest frame and a moving frame. The distillation quark smearing method is applied to improve the precision and to ensure the symmetric correlators by using the same interpolating operators at sink and source. The scattering amplitudes are extracted from the finite-volume spectra using the Lüscher's finite-volume method. At the studied pion mass, both the $^{3} S_{1}$ (deuteron) and $^{1} S_{0}$ (di-neutron) channels exhibit a virtual state pole, with binding energies of $6_{- 3}^{+ 5}$ MeV and $1 1_{- 5}^{+ 6}$ MeV, respectively. To investigate the effects of the left-hand cut, an alternative method -- the Non-Perturbative Hamiltonian framework (NPHF) -- is used for the scattering analysis and yields consistent results with those from the Lüscher method.
↳ hep-lathep-phnucl-thPRD(2026)·0 citations
14
Stable minimum principles for scattering states
Scott Lawrence · Yukari Yamauchi
Quantum-mechanical scattering states are energy eigenstates obeying particular boundary conditions, whose behavior at infinity encodes the S-matrix which defines the outcoming of scattering experiments. With an eye toward numerical algorithms for computing nonrelativistic S-matrices, we present a family of stable minimum principles for scattering states. States that approximately satisfy these minimum principles are shown to have a bounded difference with the true scattering states. These minimum principles and stability estimates can be used to obtain rigorous bounds on scattering amplitudes. We show that these minimum principles are applicable to momentum-dependent potentials, long-range (Coulomb) interactions, and elastic or inelastic scattering of bound states.
↳ quant-phmath-phmath.MPnucl-th1 citation
15
Identifying observable MeV lines from the decays of weak and main $r$ -process isotopes in mergers
Maude Lariviere · Nicole Vassh · Yanwen Deng · Xilu Wang · Rebecca Surman
We consider predictions for the MeV gamma-ray spectrum emitted by the $β$ decays of freshly synthesized isotopes from a neutron star merger at timescales of relevance for post-merger (days) and remnant (years) emission. We develop a search algorithm to identify observable spectral peaks and then determine if a specific isotope has a dominant emission line producing the spectral feature. We predict emission spectra using nucleosynthesis calculations which consider nuclear models with distinct masses, $β$ -decays, and fission properties as well as variations on main ( $A > 130$ ) and weak ( $A < 130$ ) $r$ -process astrophysical conditions. We tabulate all lines from decaying isotopes that our procedure identifies and provide the predicted range in time over which each line could be visible. We find that Rh-106 presents a unique opportunity to distinguish between main and weak $r$ -process emission, as our calculated spectrum above $\sim 1$ MeV for an event dominated by the weak $r$ process is identical to the Rh-106 emission spectrum from $\sim$ 0.2 to $\sim$ 17 years. We further find emission from species such as Hf-181, Ta-182, Ta-184, and Re-188 offers the potential to be able to distinguish between nuclear models. We investigate whether the 2.6 MeV strong gamma-ray line from Tl-208 is predicted to be robustly observable across calculation variations on both timescale of days and years. We find Tl-208 to consistently shine through on the order of years, though it can face competition from Ga-72 and La-140 at early times ( $\sim$ days). We additionally highlight numerous isotopes of interest for observation and nuclear experiment.
↳ astro-ph.HEnucl-th0 citations
16
An Analysis on the Parton Distribution Functions of Heavy Mesons
Satyajit Puhan🇮🇳
In this work, we investigate the constituent parton distribution functions (PDFs) of the kaon and heavy pseudoscalar mesons within the light-cone quark model. Starting from the initial-scale quark and antiquark PDFs, obtained by evaluating the quark--quark correlation functions for individual mesons, we perform quantum chromodynamics (QCD) evolution to determine their partonic structure at higher energy scales. The QCD evolution is carried out using the next-to-leading-order (NLO) Dokshitzer--Gribov--Lipatov--Altarelli--Parisi (DGLAP) equations. We further compute the average longitudinal momentum fractions carried by the individual constituents at both the model and evolved scales. In addition, we predict the NLO structure functions of the kaon at energy scales relevant to the upcoming Electron--Ion Collider (EIC). For the COMPASS++/AMBER experiment, we also present detailed predictions for the NLO Drell--Yan cross sections induced by both $K^{+}$ and $K^{-}$ beams, using carbon, tungsten, and aluminum as nuclear targets. Finally, we demonstrate the dominance of the heavier constituents over the lighter constituents in heavy mesons in terms of the momentum fractions they carry.
↳ hep-phnucl-thPRD(2026)·2 citations
17
Charged-current neutrino opacity within the relativistic Hartree-Fock framework for astrophysical simulations of core-collapse supernovae and binary neutron star mergers
Kamil Sokołowski · Anil Kumar🇵🇱 · Tobias Fischer🇵🇱
Neutrinos and their weak interactions play a vital role in the physics of core-collapse supernovae and binary neutron star mergers. Their description within astrophysical simulations, including the weak rates, is of pivotal importance not only for the prediction of accurate neutrino fluxes and spectra, including the associated conditions relevant to nucleosynthesis, neutrinos are also responsible for heating and cooling of the stellar plasma as well as the transport of lepton number and entropy. In the present article, we develop an essential improvement of the description of the underlying nuclear medium, necessary for the calculations of charged-current weak rates, with the inclusion of explicitly momentum-dependent nuclear interactions. To this end, we introduce the relativistic Hartree-Fock (RHF) approach and the associated momentum-dependent nucleon self-energies. We discuss the resulting neutrino and antineutrino opacities and find large discrepancies comparing the weak rates at the RHF level with those of commonly used relativistic mean-field (RMF) models; in particular, we observe a substantial shift of previously reported large medium-dependent modifications associated with the RMF approach.
↳ astro-ph.HEhep-phnucl-th2 citations
18
MAGE-HEP: Monte Carlo Analysis and Graphical Environment for High-Energy Physics
Rishabh Gupta🇮🇳 · Kangkan Goswami🇮🇳 · Suraj Prasad🇮🇳 · Raghunath Sahoo🇮🇳
Monte Carlo event generators are central to high-energy physics analysis. However, workflows based on handwritten scripts can be difficult to reuse, modify, and reproduce when multiple Monte Carlo models, tune variations, run variations, and output formats are involved. We present MAGE-HEP, short for Monte Carlo Analysis and Graphical Environment for High-Energy Physics, a Graphical User Interface (GUI) driven workflow environment for reproducible Monte Carlo-based analyses in high-energy physics. MAGE-HEP organizes analysis workflows through a project-study-run hierarchy. The project stores the workspace, the study stores the reusable analysis context, and each run represents a controlled execution of that context. The MAGE-HEP Node API provides the analysis-building layer for defining generator configurations, observables, selections, output rules, and generated C++/ROOT analysis code. A study context can be inspected, reused, or exported as a \texttt{.mcx} context bundle, while the project state can be exported as a portable \texttt{.mgp} bundle. The current beta implementation validates the core idea using a PYTHIA8 and ROOT workflow. It includes background execution, manifest-based run tracking, live ROOT inspection, and particle-table summaries for supported output layouts. This paper describes the architecture, workflow, and current beta implementation of MAGE-HEP.
↳ hep-phhep-exhep-thnucl-ex+10 citations
19
Positivity of the effective range for finite range attractive potentials with a repulsive core
Davide Germani🇮🇹
In the phenomenological study of exotic hadrons, the sign of the effective range, $r_{0}$ , is invoked as a criterion to distinguish between compact multiquark configurations (associated with $r_{0} < 0$ ) and loosely bound hadronic molecules ( $r_{0} > 0$ ). Motivated by this, we investigate the fundamental constraints on the sign of the effective range for single-channel local interactions. We rigorously prove that for finite-range potentials, characterized by an inner repulsive core and an outer attractive tail, the effective range remains strictly positive provided that the scattering length is greater than the range of the potential ( $a > R$ ).
↳ hep-phnucl-thquant-ph0 citations
20
Gravitational form factors of light mesons from Basis Light-Front Quantization
Amrita Sain🇨🇳 · Sreeraj Nair🇨🇳 · Chandan Mondal🇨🇳 · Xingbo Zhao🇨🇳 · James P. Vary🇺🇸
We compute the gravitational form factors (GFFs) of the pion and kaon using their light-front wave functions within the Basis Light-Front Quantization framework. The wave functions are obtained by solving a light-front effective Hamiltonian that incorporates three-dimensional confinement along with a color-singlet Nambu--Jona-Lasinio interaction between the constituent quark and antiquark. The form factor $A (Q^{2})$ is found to be in overall agreement with recent lattice QCD and dispersive results. In contrast, $D (Q^{2})$ is enhanced in magnitude at low $Q^{2}$ relative to both lattice QCD and dispersive determinations. This behavior arises from extracting the $D$ -term using transverse components of the QCD energy--momentum tensor, which are more sensitive to the small- $x$ region and to light-front zero-mode effects in the present truncated framework. Using the resulting GFFs, we determine the mass (matter) and mechanical radii of the pion and kaon and analyze their mechanical structure through the corresponding pressure and shear-force distributions.
↳ hep-phhep-thnucl-th0 citations
21
Quark and gluon tomography of the helium-4 nucleus
V. Martínez-Fernández🇫🇷 · B. Pire🇫🇷 · P. Sznajder🇵🇱 · J. Wagner🇵🇱
QCD collinear factorization allows coherent hard exclusive reactions to reveal the quark-gluon structure of light nuclei, enabling their 3D tomography. We study elastic form factors and deeply virtual Compton scattering on a helium-4 target, achieving theoretical precision unprecedented even in proton studies. Constraining generalized parton distributions at next-to-leading order in $α_{s}$ , incorporating kinematic twist corrections, and using full evolution equations, we provide the first tomography of a light nucleus, revealing distinct transverse spatial distributions of quarks and gluons.
↳ hep-phhep-exnucl-exnucl-th2 citations

Affiliations

first authorsco-authorsvia INSPIRE