J 2022

New interior model of neutron stars

POSADA AGUIRRE, Nelson Camilo, Jan HLADÍK and Zdeněk STUCHLÍK

Basic information

Original name

New interior model of neutron stars

Authors

POSADA AGUIRRE, Nelson Camilo (170 Colombia, belonging to the institution), Jan HLADÍK (203 Czech Republic, belonging to the institution) and Zdeněk STUCHLÍK (203 Czech Republic, belonging to the institution)

Edition

Physical Review D, 2022, 2470-0010

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10308 Astronomy

Country of publisher

United States of America

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

RIV identification code

RIV/47813059:19630/22:A0000205

Organization unit

Institute of physics in Opava

UT WoS

000807653700009

Keywords in English

neutron stars;Tolman VII solution; tidal Love number;tidal deformability

Tags

Tags

International impact, Reviewed
Změněno: 7/3/2023 13:54, Mgr. Pavlína Jalůvková

Abstract

V originále

The Tolman VII solution is considered by some as one of the few analytical solutions to Einstein???s equations, which describes approximately well the interior of neutron stars (NSs). This solution is characterized by the mass M, radius R, and an energy density that varies quadratically with the radial coordinate r. Recently, Jiang and Yagi proposed a modification of this solution, the so-called modified Tolman VII (MTVII) solution, by introducing an additional quartic term to the energy density radial profile. The MTVII solution is an approximate solution to Einstein???s equation, which includes a new parameter ?? that allows the solution to have a better agreement with the energy density profiles for realistic NSs. Here we consider the MTVII solution, showing that for certain values of the parameter ?? and compactness C this solution manifests a region of negative pressure near the surface which leads to negative values of the tidal Love number. To alleviate these drawbacks, we introduce an exact version of the MTVII solution obtained by solving numerically Einstein???s equations for the MTVII energy density profile. As an application of our new exact MTVII (EMTVII) solution, we calculate the tidal Love number and tidal deformability, as a function of C, for different values of the parameter ??. We find that the EMTVII solution predicts a positive tidal Love number for the whole range of allowed values of parameters ??C; ????, in agreement with previous results for realistic NSs.