Orbital Period Variation of KIC 10544976: Applegate Mechanism versus Light Travel Time Effect

Autor(es)

Almeida, L. A. ^{[1, 2]} ; de Almeida, L. ^[1] ; Damineli, A. ^[2] ; Rodrigues, V, C. ; Castro, M. ^[1] ; Lopes, C. E. Ferreira ^[3] ; Jablonski, F. ^[3] ; do Nascimento Jr, J-D ; Pereira, M. G. ^[4]

Afiliação do(s) autor(es)

^[1] Univ Fed Rio Grande do Norte, Dept Fis Teor & Expt, CP 1641, BR-59072970 Natal, RN - Brazil

^[2] Inst Astron Geofis & Ciencias Atmosfer, Rua Matao 1226, Cidade Univ, BR-05508090 Sao Paulo, SP - Brazil

^[3] Rodrigues, C., V, MCTIC, Inst Nacl Pesquisas Espaciais, Ave Astronautas 1758, BR-12227010 Sao Jose Dos Campos, SP - Brazil

^[4] Univ Estadual Feira de Santana, Av Transnordestina S-N, BR-44036900 Feira De Santana, BA - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ASTRONOMICAL JOURNAL; v. 157, n. 4 APR 2019.
• Citações Web of Science: 2

Resumo

In recent years, several close post-common-envelope eclipsing binaries have been found to show cyclic eclipse timing variations (ETVs). This effect is usually interpreted either as the gravitational interaction among circumbinary bodies and the host binary-known as the light travel time (LTT) effect-or as the quadrupole moment variations in one magnetic active component-known as the Applegate mechanism. In this study, we present an analysis of the ETV and the magnetic cycle of the close binary KIC 10544976. This system is composed of a white dwarf and a red dwarf in a short orbital period (0.35 days) and was monitored by ground-based telescopes between 2005 and 2017 and by the Kepler satellite between 2009 and 2013. Using the Kepler data, we derived the magnetic cycle of the red dwarf by two ways: the rate and energy of flares and the variability due to spots. Both methods resulted in a cycle of similar to 600 days, which is in agreement with magnetic cycles measured for single low-mass stars. The orbital period of KIC 10544976 shows only one long-term variation which can be fitted by an LTT effect with period of similar to 16.8 yr. Hence, one possible explanation for the ETVs is the presence of a circumbinary body with a minimal mass of similar to 13.4 M-Jup.In- the particular scenario of coplanarity between the external body and the inner binary, the third body mass is also similar to 13.4 M-Jup. In this case, the circumbinary planet must either have survived the evolution of the host binary or have been formed as a consequence of its evolution. (AU)

• Processo FAPESP: 12/09716-6 - Distâncias precisas de aglomerados jovens através de binárias eclipsantes massivas
• Beneficiário: Leonardo Andrade de Almeida
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/26258-4 - Matéria superdensa no universo
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• Processo FAPESP: 13/18245-0 - Soluções orbitais espectroscópicas completas para mais de 100 binárias massivas na região do "starburst" 30 Dourados
• Beneficiário: Leonardo Andrade de Almeida
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado
• Processo FAPESP: 11/51680-6 - Explorando o universo: da formação de galáxias aos planetas tipo-Terra, com o Telescópio Gigante Magellan
• Beneficiário: Laerte Sodré Junior
• Modalidade de apoio: Auxílio à Pesquisa - Projetos Especiais