Saved in:
Bibliographic Details
Main Authors: Panotopoulos, G., Övgün, A., Iqbal, T., Kumaran, Y., Sharma, B. K.
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2602.15818
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908838193528832
author Panotopoulos, G.
Övgün, A.
Iqbal, T.
Kumaran, Y.
Sharma, B. K.
author_facet Panotopoulos, G.
Övgün, A.
Iqbal, T.
Kumaran, Y.
Sharma, B. K.
contents Radial oscillations provide a clean dynamical test of the high-density stiffness of neutron-star equations of state. We study spherically symmetric pulsations of nonrotating relativistic stars built from cold, charge-neutral, $β$-equilibrated pure nucleonic matter described within relativistic mean-field theory. As a baseline we adopt the UCIa parameter set [Astron. Astro-phys. 689, A242 (2024)], and we implement high-density stiffening via the $σ$-cut scheme by adding a regulator potential $U_{\rm cut}(σ)$ [Phys. Rev. C 92, no.5, 052801 (2015), Phys. Rev. C 106, no.5, 055806 (2022)]. For representative choices $f_s=0$ (no cutoff) and $f_s=0.58$ (stiffened), we solve the Tolman-Oppenheimer-Volkoff and tidal perturbation equations to obtain equilibrium sequences, mass-radius relations, and tidal deformabilities. We then derive and solve the linear general-relativistic radial pulsation equations to compute the eigenfrequencies and eigenfunctions of the fundamental and overtone modes. The $σ$-cutoff suppresses the growth of the scalar field at supranuclear density, increases the pressure, and shifts the maximum mass, radii, and $Λ_{1.4}$ accordingly, while systematically raising the radial-mode frequencies at fixed mass. Using the sign change of $ω_0^2$ as a stability criterion, we identify stiffened models that remain radially stable up to the observed $\sim 2M_\odot$ mass scale and are consistent with current multimessenger constraints, demonstrating how radial spectra complement static EoS tests.
format Preprint
id arxiv_https___arxiv_org_abs_2602_15818
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Radial oscillations of pulsating neutron stars: The UCIa equation-of-state case
Panotopoulos, G.
Övgün, A.
Iqbal, T.
Kumaran, Y.
Sharma, B. K.
Nuclear Theory
Solar and Stellar Astrophysics
General Relativity and Quantum Cosmology
Radial oscillations provide a clean dynamical test of the high-density stiffness of neutron-star equations of state. We study spherically symmetric pulsations of nonrotating relativistic stars built from cold, charge-neutral, $β$-equilibrated pure nucleonic matter described within relativistic mean-field theory. As a baseline we adopt the UCIa parameter set [Astron. Astro-phys. 689, A242 (2024)], and we implement high-density stiffening via the $σ$-cut scheme by adding a regulator potential $U_{\rm cut}(σ)$ [Phys. Rev. C 92, no.5, 052801 (2015), Phys. Rev. C 106, no.5, 055806 (2022)]. For representative choices $f_s=0$ (no cutoff) and $f_s=0.58$ (stiffened), we solve the Tolman-Oppenheimer-Volkoff and tidal perturbation equations to obtain equilibrium sequences, mass-radius relations, and tidal deformabilities. We then derive and solve the linear general-relativistic radial pulsation equations to compute the eigenfrequencies and eigenfunctions of the fundamental and overtone modes. The $σ$-cutoff suppresses the growth of the scalar field at supranuclear density, increases the pressure, and shifts the maximum mass, radii, and $Λ_{1.4}$ accordingly, while systematically raising the radial-mode frequencies at fixed mass. Using the sign change of $ω_0^2$ as a stability criterion, we identify stiffened models that remain radially stable up to the observed $\sim 2M_\odot$ mass scale and are consistent with current multimessenger constraints, demonstrating how radial spectra complement static EoS tests.
title Radial oscillations of pulsating neutron stars: The UCIa equation-of-state case
topic Nuclear Theory
Solar and Stellar Astrophysics
General Relativity and Quantum Cosmology
url https://arxiv.org/abs/2602.15818