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arXiv · 2609.08534

Nuclear equation-of-state effects on the two-dimensional post-outburst thermal evolution of magnetized neutron-star crusts

Abstract

We present a controlled two-dimensional study of nuclear-equation-of-state (EOS) effects on the post-outburst thermal relaxation of magnetized neutron-star crusts. Six EOS models are evolved at a fixed gravitational mass of $1.4 M_{\odot}$ with EOS-specific TOV backgrounds, crust compositions, and transport inputs under identical magnetic-field and heating prescriptions. Our analysis combines self-consistent multi-EOS evolution with a BSk-family factorization that separates structural, microphysical, and interaction contributions, together with an accepted-step energy ledger and a numerical-sensitivity budget. The models show EOS-dependent changes in both the early response and the later redistribution of heat between the surface, crust, and inner boundary; light-curve crossings near $10^2$ days demonstrate that the EOS effect is not a simple luminosity rescaling. By 1000 days the cumulative surface-photon energy fraction differs by less than one percentage point, whereas the internal energy partition differs much more strongly. The updated sensitivity tests show that the late-time luminosity differences and the largest peak contrasts exceed the corresponding BSk24 numerical-sensitivity scales, while the smallest early peak contrast remains less securely resolved. The calculations are intended as a reproducible EOS-sensitivity benchmark rather than an observational fit.

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Wei-Feng Zhang, Zhi-Fu Gao, Wen-Qi Ma, Na Wang, Yan-ling Liu. 2026-09-08. Nuclear equation-of-state effects on the two-dimensional post-outburst thermal evolution of magnetized neutron-star crusts. https://arxiv.org/abs/2609.08534

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