Nuclear Theory·nucl-th

Thursday·February 26, 2026

8 papers—2 primary·6 cross-listed

01
Isotope-Resolved Ba and Xe Yields in Actinide Fission and Correlated Heavy--Light Fragment Systematics
K. Pomorski · A. Augustyn · T. Cap · Y. J. Chen · M. Kowal · B. Nerlo-Pomorska · M. Warda · Z. G. Xiao
Isotope-resolved post-neutron fission yields in the Ba and Xe chains are calculated and benchmarked against evaluated reference data, with emphasis on element-resolved isotopic chains $Y (N_{f})$ at fixed fragment charge $Z$ and on the consistency of heavy--light fragment correlations. Calculations are performed within a four-dimensional (4D) Langevin framework employing Fourier-over-Spheroid shape parametrization. The benchmark covers spontaneous fission of selected Cm and Cf isotopes (including $^{244, 246}$ Cm and $^{250}$ Cf) as well as neutron-induced fission at thermal and 14-MeV energies for representative actinides in the Th--Pu region (including $^{229}$ Th, $^{235}$ U, $^{239}$ Pu, and $^{249}$ Cf). The dominant neutron-number maxima are reproduced for a large fraction of the isotopic chains considered, indicating that the mean charge partition and the average neutron content of the main fission channels are described consistently. A systematic residual discrepancy is observed in the isotopic widths: the calculated yields often fall off too rapidly on the distribution tails, producing distributions that are narrower than the evaluated data, most notably for heavy-fragment chains.
nucl-thPRC(2026)·1 citation
02
Ab initio calculations of nuclear charge radii across and beyond $^{132}$ Sn: Putting chiral EFT nuclear interactions to the test
Pepijn Demol🇧🇪 · Urban Vernik🇧🇪 · Thomas Duguet🇧🇪 · Alexander Tichai🇩🇪
Charge radii are investigated along the Tin isotopic chain via ab initio Bogoliubov coupled cluster calculations at the singles and doubles level. In addition to the reproduction of absolute radii, the parabolic behavior of isotopic shifts between the N = 50 and N = 82 magic numbers and the kink through $^{132}$ Sn are shown to provide stringent tests for state-of-the-art chiral effective field theory ( $χ$ EFT) inter-nucleon interactions. Indeed, none of the employed fine-tuned interactions can capture all such key characteristics. Eventually, the pronounced sensitivity of the results to the employed Hamiltonian beyond $^{132}$ Sn provides a unique playground to pin down critical attributes of $χ$ EFT inter-nucleon interactions in the future. This calls for measuring isotopic shifts both towards $^{100}$ Sn and beyond $^{134}$ Sn, as well as for performing high-accuracy ab initio calculations of mean-square radii in heavy open-shell nuclei by adding both triples corrections to the many-body wave function and the two-body charge density correction to the operator
nucl-thnucl-exPLB(2026)·5 citations
03
Lorentz-boosted diffusion: initial value formulation and exact solutions
Lorenzo Gavassino
It is well known that the diffusion equation, when treated as a stand-alone partial differential equation, exhibits exponential instabilities in boosted frames, which render the corresponding initial-value problem ill-posed. Recently, however, it was shown that Fick-type diffusion arises as the exact hydrodynamic sector of relativistic Fokker-Planck kinetic theory. In this work, we exploit this kinetic embedding to formulate a modified initial-value problem for one-dimensional Lorentz-boosted diffusion. We show that the resulting dynamics are well posed both forward and backward in time, provided the boosted density profiles admit a kinetic-theory realization. Such profiles form a space of band-limited functions, within which the evolution can be expressed as a discrete superposition of spatially sampled initial data, weighted by a Shannon-Whittaker-type Green function defined on the full Minkowski plane. The Green function is obtained in closed analytic form.
↳ math-phgr-qchep-thmath.MP+1PRD(2026)·3 citations
04
Collapse of Magnetized White Dwarfs as site of Heavy Element Formation and Kilonova Signal
Tetyana Pitik🇺🇸 · David Radice🇺🇸 · Daniel Kasen🇺🇸 · Fabio Magistrelli🇩🇪 · Patrick Chi-Kit Cheong🇺🇸 · Sebastiano Bernuzzi🇩🇪
We present the first end-to-end calculation connecting the accretion-induced collapse (AIC) of a magnetized, rapidly rotating white dwarf to observable kilonova signatures, combining 2D general-relativistic neutrino-magnetohydrodynamic simulations, followed by radiation hydrodynamics with in-situ nuclear network and 2D Monte Carlo radiative transfer with spatially resolved heating rates. Unlike all previous unmagnetized AIC models - which predicted proton-rich, $^{56}$ Ni-dominated ejecta - strong magnetic fields eject $\sim 0.2 M_{⊙}$ of neutron-rich material $(⟨ Y_{e} ⟩ \sim 0.24)$ on dynamical timescales, before neutrino irradiation can raise the electron fraction, enabling strong $r$ -process nucleosynthesis up to and beyond the third peak. The resulting kilonova is lanthanide-rich $(X_{lan} \approx 8%)$ and dominated by near-infrared emission. We compute synthetic light curves in the LSST and JWST bands and find striking agreement, without parameter tuning, between the observations of AT 2023vfi/GRB 230307A and our broadband light curves for polar viewing angles. These results establish magnetized AIC as a viable channel for heavy $r$ -process element production and a compelling progenitor candidate for long-duration gamma-ray bursts with kilonova signatures.
↳ astro-ph.HEnucl-thMNRAS(2026)·6 citations
05
Shock-induced chiral magnetic effect
Steven P. Harris🇺🇸 · Srimoyee Sen🇺🇸
Weak-interaction-mediated chiral imbalance generation in idealized massless electrons during core-collapse supernovae was once proposed to be the source of strong magnetic fields found in neutron stars. The effect goes by the name of chiral plasma instability (CPI). However, it was found that a finite electron mass damps out this process, inactivating the instability and preventing magnetic field growth. In this work we show that the instability can survive in the presence of abrupt density and temperature perturbation that drives the system sufficiently far out of weak equilibrium. As an example, we work with such perturbations generated by shockwaves which are common during both core collapse as well as neutron star mergers. We find that the chiral imbalance resulting from shock waves, under the right conditions of density and temperature, can sustain the chiral plasma instability despite the damping from the electron mass. Additionally, in an already magnetized medium, the chiral magnetic effect resulting from shock wave density and temperature perturbation can generate substantial ohmic heating. Our results imply that shockwaves generated in core-collapse supernovae and merging neutron stars can act as a source of strong heating in a magnetized medium as well as CPI.
↳ astro-ph.HEhep-phnucl-thPRD(2026)·0 citations
06
Phase diagram of the single-flavor Gross--Neveu--Wilson model from the Grassmann corner transfer matrix renormalization group
Jian-Gang Kong🇨🇳 · Shinichiro Akiyama🇯🇵 · Tao Shi🇨🇳 · Z. Y. Xie🇨🇳
We investigate the phase structure of the single-flavor Gross--Neveu model with Wilson fermions using the Grassmann corner transfer matrix renormalization group (CTMRG). The path integral is formulated as a two-dimensional Grassmann tensor network and approximately contracted by the Grassmann CTMRG algorithm. We investigate the phase diagram by varying the fermion mass and the four-fermion coupling, using the pseudoscalar condensate as an order parameter for the $Z_{2}$ parity symmetry breaking phase. The universality classes of the phase boundaries are identified through the central charge $c$ obtained via scaling analysis of the entanglement entropy. Furthermore, we extract the quantity related to the entanglement spectrum from the converged CTMRG environments, allowing us to distinguish the topological insulator phase and the trivial phase. The resulting phase structure suggests that the Aoki phase is separated from the other phases by critical lines characterized by $c = 1/2$ , while the critical lines with $c = 1$ separate the topological insulating and trivial phases. Our numerical results also indicate that the Aoki phase does not persist in the strong-coupling regime for the single-flavor theory.
↳ hep-latcond-mat.str-elnucl-thPRD(2026)·3 citations
07
A Consistent Holographic Analysis of Anomaly-induced Charge Transport in the D3/D7 Model
Shin Nakamura🇯🇵 · Kensei Tanaka🇯🇵
We propose a scheme to correctly incorporate the contribution of the chiral anomaly in the D3/D7 model to calculate chiral transport phenomena. To ensure the D7-brane wraps S^5 appropriately and the Wess-Zumino term is switched on, we allow the D7-brane to rotate in the compactified extra directions and perform the analysis accordingly. To demonstrate that this calculation procedure works well, we specifically compute the magnetoresistance in the D3/D7 model. We find that a finite axial chemical potential is realized and the negative magnetoresistance is enhanced by the anomaly contribution.
↳ hep-thnucl-thJHEP(2026)·1 citation
08
Trade-offs in Gauss's law error correction for lattice gauge theory quantum simulations
Balint Pato🇺🇸 · Natalie Klco🇺🇸
Gauss's law-based quantum error correction (GLQEC) offers a promising approach to reducing qubit overhead in lattice gauge theory simulations by leveraging built-in symmetries. For applications of GLQEC to 1+1D lattice quantum electrodynamics (QED), we identify two significant trade-offs. First, we prove via dimension-counting arguments that GLQEC requires periodic electric fields, thereby constraining the design space for lattice QED simulations. Second, we numerically compare GLQEC with a universal quantum error correction (UQEC) code, specifically the $d = 3$ bitflip repetition code, and find that while GLQEC can achieve lower logical error rates in single-round error correction, it exhibits faster decoherence to the steady-state mixed ensemble under multiple rounds. The mixing speed penalty is manifest in observables of interest for both memory experiments and Hamiltonian evolution. We identify a mixing speed threshold, $p_{t h} = 0.277 (2)$ , above which using GLQEC exhibits even faster decoherence than without error correction. Our results highlight fundamental limitations of symmetry-based error correction schemes and inform corresponding constraints on formulations of lattice gauge theories compatible with error-robust quantum simulation techniques.
↳ quant-phhep-latnucl-th10 citations

Affiliations

first authorsco-authorsvia INSPIRE