Chirping compact stars: gravitational radiation and detection degeneracy with binaries

ABSTRACT:Abstract. Compressible, Riemann S-type ellipsoids can emit gravitational waves (GWs) with a chirp-like behavior (hereafter chirping ellipsoids, CELs). We show that the GW frequency amplitude evolution of CELs (mass ∼ 1 M⊙, radius ∼ 103 km, polytropic equation of state with index n ≈ 3) is indistinguishable from that emitted by double white dwarfs and by extreme mass-ratio inspirals (EMRIs) composed of an intermediate-mass (e.g. 103 M⊙) black hole and a planet-like (e.g. 10−4 M⊙) companion, in the frequency interval within the detector sensitivity band in which the GW emission of these systems is quasi-monochromatic. For reasonable astrophysical assumptions, the local universe density rate of CELs, double white dwarfs, and EMRIs in the mass range here considered are very similar, posing a detection degeneracy challenge for space-based GW detectors. We outline the astrophysical implications of this CEL-binary detection degeneracy by space-based GW-detection facilities.

• Autores: Zuluaga Callejas, Jorge Iván; Rodríguez, José Fernando; Rueda, Jorge A.; Ruffini, Remo; Blanco Iglesias, José Miguel; Lorén Aguilar, Pablo
• Tipo de recurso: Article of investigation
• Fecha de publicación: 2023
• Institución: Universidad de Antioquia
• Repositorio: Repositorio UdeA
• Idioma: eng
• OAI Identifier: oai:bibliotecadigital.udea.edu.co:10495/40419
• Acceso en línea: https://hdl.handle.net/10495/40419
• Palabra clave: Estrellas; Stars; Radiación gravitacional; Gravitational radiation
• Rights: openAccess
• License: http://creativecommons.org/licenses/by-nc-sa/2.5/co/