Lithium abundance and activity in a sample of RS Canum Venaticorum and BY Draconis stars

Observations of the Li i doublet at 6707.8 angstrom for a sample of active binary systems RS CVn and By Dra have been carried out at the Calar Alto Observatory with the 2.2 m telescope. In addition, some single stars with different chromospheric activity levels have also been observed mainly for com...

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Detalles Bibliográficos
Autores: Fernández Figueroa, María José, Barrado y Navascués, D., Castro Rubio, Elisa De, Cornide Castro-Piñeiro, Manuel
Tipo de recurso: artículo
Fecha de publicación:1993
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/59664
Acceso en línea:https://hdl.handle.net/20.500.14352/59664
Access Level:acceso abierto
Palabra clave:52
Main-sequence stars
Solar-type stars
F-stars
Chromospheric activity
Stellar evolution
Binary stars
Giant stars
G-dwarfs
Rotation
Hyades
Astrofísica
Astronomía (Física)
Descripción
Sumario:Observations of the Li i doublet at 6707.8 angstrom for a sample of active binary systems RS CVn and By Dra have been carried out at the Calar Alto Observatory with the 2.2 m telescope. In addition, some single stars with different chromospheric activity levels have also been observed mainly for comparison purposes. Gaussian fits have been performed in order to separate the Fe I line at 6707.4 angstrom which is usually blended with the Li I doublet. Once the fit was achieved, the equivalent width was measured for each separated line. The contributions due to the continuum from both components have been taken into account to correct the equivalent width measurements. A curve-of-growth method has been used to derive lithium abundances. We have obtained a Li excess in the binary systems, in particular the K type stars. A correlation of the Li abundance with the activity levels is confirmed, as it was found by other authors, but RS CVn and BY Dra systems are 0.5 dex more active than single stars for the same Li abundance.