POSADA AGUIRRE, Nelson Camilo and Cecilia CHIRENTI. On the radial stability of ultra-compact Schwarzschild stars beyond the Buchdahl limit. Classical and Quantum Gravity. 2019, vol. 36, No 6, p. "065004-1"-"065004-14", 14 pp. ISSN 0264-9381. Available from: https://dx.doi.org/10.1088/1361-6382/ab0526.
Other formats:   BibTeX LaTeX RIS
Basic information
Original name On the radial stability of ultra-compact Schwarzschild stars beyond the Buchdahl limit
Authors POSADA AGUIRRE, Nelson Camilo (170 Colombia, guarantor, belonging to the institution) and Cecilia CHIRENTI (76 Brazil).
Edition Classical and Quantum Gravity, 2019, 0264-9381.
Other information
Original language English
Type of outcome Article in a journal
Field of Study 10308 Astronomy
Country of publisher United Kingdom of Great Britain and Northern Ireland
Confidentiality degree is not subject to a state or trade secret
WWW URL
RIV identification code RIV/47813059:19240/19:A0000555
Organization unit Faculty of Philosophy and Science in Opava
Doi http://dx.doi.org/10.1088/1361-6382/ab0526
UT WoS 000459242900001
Keywords in English ultra-compact stars; radial oscillations; stellar stability; interior solution
Tags FÚ, RCTPA, RIVOK
Tags International impact, Reviewed
Changed by Changed by: Ing. Petra Skoumalová, učo 50554. Changed: 21/4/2020 11:41.
Abstract
In this paper we used the theory of adiabatic radial oscillations developed by Chandrasekhar to study the conditions for dynamical stability of constant energy-density stars, or Schwarzschild stars, in the unstudied ultra compact regime beyond the Buchdahl limit, that is, for configurations with radius R in the range R_S < R < (9/8)R_S, where R_S is the Schwarzschild radius of the star. These recently found analytical solutions exhibit a negative pressure region in their centre and, in the limit when R -> R_S, the full interior region of the star becomes filled with negative pressure. Here we present a systematic analysis of the stability of these configurations against radial perturbations. We found that, contrary to the usual expectation found in many classical works, the ultra compact Schwarzschild star is stable against radial oscillations. We computed values of the critical adiabatic index gamma_(c) for several stellar models with varying radius R/R_s and found that it also approaches a finite value as R/R_S -> 1.
PrintDisplayed: 21/5/2024 01:18