A circumbinary planet in orbit around the short-period white dwarf eclipsing binary RR Cae

By using six newly determined mid-eclipse times together with those collected from the literature, we have found that the observed minus calculated (O−C) curve of RR Cae shows a cyclic change with a period of 11.9 yr and an amplitude of 14.3 s while it undergoes an upward parabolic variation [reveal...

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Detalles Bibliográficos
Autores: Qian S.-B., Liu, L., Zhu L.-Y., Dai Z.-B., Fernandez Lajus, Eduardo Eusebio, Baume, Gustavo Luis
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/232325
Acceso en línea:http://hdl.handle.net/11336/232325
Access Level:acceso abierto
Palabra clave:STARS: BINARIES: CLOSE
STARS: BINARIES: ECLIPSING
STARS: INDIVIDUALS (RR CAE)
STARS: WHITE DWARFS
STARS: PLANETARY SYSTEMS
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:By using six newly determined mid-eclipse times together with those collected from the literature, we have found that the observed minus calculated (O−C) curve of RR Cae shows a cyclic change with a period of 11.9 yr and an amplitude of 14.3 s while it undergoes an upward parabolic variation [revealing a long-term period increase at a rate of ˙P= +4.18(±0.20) × 10−12]. The cyclic change was analysed for the light-travel-time effect that arises from the gravitational influence of a third companion. The mass of the third body was determined to be M3sin i = 4.2(± 0.4)MJup, suggesting that it is a circumbinary giant planet when its orbital inclination is larger than 17. ◦ 6. The orbital separation of the circumbinary planet from the central eclipsing binary is about 5.3(± 0.6) au. The period increase is opposite to the changes caused by angular momentum loss via magnetic braking or/and gravitational radiation; and it cannot be explained by the mass transfer between both components because of its detached configuration. These indicate that the observed upward parabolic change is only a part of a long-period (longer than 26.3 yr) cyclic variation, which may reveal the presence of another giant circumbinary planet in a wide orbit.