English

Sensitivity of neutron star observables to microscopic nuclear parameters of realistic equations of state

Nuclear Theory 2026-03-18 v1 High Energy Astrophysical Phenomena General Relativity and Quantum Cosmology High Energy Physics - Phenomenology

Abstract

The equation of state of matter at supranuclear densities governs the astrophysical observables of neutron stars. A realistic, though complex, description is provided by the Chiral-Mean-Field model, which depends on many microscopic nuclear-physics parameters. We present a Fisher-information-inspired analysis of the sensitivity of neutron-star observables to the parameters of the Chiral-Mean-Field model at β\beta-equilibrium using SLy as a crust. We then compute neutron-star sequences and extract masses, radii, compactnesses, and tidal deformabilities. From the logarithmic derivatives of these observables with respect to each nuclear parameter, we construct a dimensionless, Fisher-inspired sensitivity matrix and perform a principal-component analysis to identify the effective combinations of nuclear parameters that most strongly affect neutron-star observables. Although the ranking depends mildly on the observable, the three most important nuclear parameters are the vacuum value of the dilaton field χ0\chi_0 (which sets the overall scale of the scalar potential and trace-anomaly contribution), the scalar singlet strength g1Xg_{1}^X (which controls the overall scalar attraction through the baryon effective masses), and the k0k_0 quadratic scalar term (which governs the curvature of the scalar potential). This framework provides a reproducible, data-driven approach to quantify parameter sensitivities in dense-matter models and to guide future Bayesian inference of nuclear information from multi-messenger astrophysical observations.

Keywords

Cite

@article{arxiv.2603.16019,
  title  = {Sensitivity of neutron star observables to microscopic nuclear parameters of realistic equations of state},
  author = {Nikolas Cruz-Camacho and Carlos Conde-Ocazionez and Veronica Dexheimer and Jacquelyn Noronha-Hostler and Nicolás Yunes},
  journal= {arXiv preprint arXiv:2603.16019},
  year   = {2026}
}

Comments

33 pages, 14 figures, 6 tables