Kepler rapidly rotating giant stars

Rapidly rotating giant stars are relatively rare and may represent important stages of stellar evolution, resulting from stellar coalescence of close binary systems or accretion of substellar companions by their hosting stars. In the present Letter, we report 17 giant stars observed in the scope of...

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Detalles Bibliográficos
Autores: Costa, A. D., Martins, B. L. Canto, Bravo, J. P., Paz-Chinchón, F., Chagas, M. L. das, Leão, I. C., Oliveira, G. Pereira de, Silva, R. Rodrigues da, Roque, S., Oliveira, L. L. A. de, Silva, D. Freire da, Medeiros, José Renan de
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:Brasil
Institución:Universidade Federal do Rio Grande do Norte (UFRN)
Repositorio:Repositório Institucional da UFRN
Idioma:inglés
OAI Identifier:oai:repositorio.ufrn.br:123456789/29083
Acceso en línea:https://repositorio.ufrn.br/jspui/handle/123456789/29083
http://dx.doi.org/10.1088/2041-8205/807/2/L21
Access Level:acceso abierto
Palabra clave:Stars: evolution
Stars: fundamental parameters
Stars: rotation
Descripción
Sumario:Rapidly rotating giant stars are relatively rare and may represent important stages of stellar evolution, resulting from stellar coalescence of close binary systems or accretion of substellar companions by their hosting stars. In the present Letter, we report 17 giant stars observed in the scope of the Kepler space mission exhibiting rapid rotation behavior. For the first time, the abnormal rotational behavior for this puzzling family of stars is revealed by direct measurements of rotation, namely from photometric rotation period, exhibiting a very short rotation period with values ranging from 13 to 55 days. This finding points to remarkable surface rotation rates, up to 18 times the rotation of the Sun. These giants are combined with six others recently listed in the literature for mid-infrared (IR) diagnostics based on Wide-field Infrared Survey Explorer information, from which a trend for an IR excess is revealed for at least one-half of the stars, but at a level far lower than the dust excess emission shown by planet-bearing main-sequence stars.