Circumbinary planets orbiting the rapidly pulsating subdwarf B-type binary NY Vir

We report here the tentative discovery of a Jovian planet in orbit around<br />the rapidly pulsating subdwarf B-type (sdB-type) eclipsing binary NY Vir. By using new determined eclipse times together those collected from the literature, we detect that the observed-calculated (O-C) curve of NY...

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Detalles Bibliográficos
Autores: Qian, S.-B., Zhu, L.-Y., Dai, Z.-B., Fernandez Lajus, Eduardo Eusebio, Xiang, F.-Y., He, J.-J.
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:11336/42477
Acceso en línea:http://hdl.handle.net/11336/42477
Access Level:acceso abierto
Palabra clave:Close binaries
Eclipsing binaries
NY VIR (estrella)
Subdwarfs
Planetary systems
https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
Descripción
Sumario:We report here the tentative discovery of a Jovian planet in orbit around<br />the rapidly pulsating subdwarf B-type (sdB-type) eclipsing binary NY Vir. By using new determined eclipse times together those collected from the literature, we detect that the observed-calculated (O-C) curve of NY Vir shows a small-amplitude cyclic variation with a period of 7.9 years and a semiamplitude of 6.1 s, while it undergoes a downward parabolic change (revealing a period decrease at a rate of _dP/dt = -9.2 x 10^-12). The periodic variation was analyzed for the light-travel time effect via the presence of a third body. The mass of the tertiary companion was determined to be M3 sin i´ = 2.3(+/-0.3) MJupiter when a total mass of 0.60 Msun for NY Vir is adopted. This suggests that it most probably is a giant circumbinary planet orbiting NY Vir at a distance of about 3.3 astronomical units (AU). Since the rate of period decrease can not be explained by true angular momentum loss caused by gravitational radiation or/and magnetic braking, the observed downward parabolic change in the O-C diagram may be only a part of a long-period (longer than 15 years) cyclic variation, which may reveal the presence of another Jovian planet (about 2.5 MJupiter) in the system.