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oai:docta.ucm.es:20.500.14352/596622024-09-05T14:43:36Zcom_20.500.14352_14col_20.500.14352_15

Application of the spectral subtraction technique to the Ca II H & K and H_ε lines in a sample of chromospherically active binaries Montes Gutiérrez, David Castro Rubio, Elisa De Fernández Figueroa, María José Cornide Castro-Piñeiro, Manuel 52 Late-type stars Main-sequence stars Solar-type stars RS-CVN system Alpha emission Draconis variables Profiles Catalog Discovery Astrofísica Astronomía (Física) © 1995 EDP Sciences. This work has been supported by the Universidad Complutense de Madrid and the Spanish Dirección General de Investigación Científica y Técnica (DGICYT) under grant PB91-0348. We would like to thank the referee K.G. Strassmeier for suggesting several improvements and clarifications. We present new spectroscopic observations in the Ca II H & K line region for a sample of 28 chromospherically active binary systems (RS CVn and BY Dra classes), with different activity levels. By using the spectral subtraction technique (subtraction of a synthesized stellar spectrum constructed from reference stars of similar spectral type and luminosity class) we obtain the active-chromosphere contribution to the Ca II H & K lines and to the H_ε line when it is present. We have compared the emission equivalent widths obtained with this technique with those obtained by reconstruction of the absorption line profile below the emission peak(s). The emissions arising from each individual star were obtained when it was possible to deblend the contribution of both components. The Ca II line profiles corresponding to different seasons and orbital phases are analysed in order to determine the contribution of each component and to study the chromospheric activity variations. Universidad Complutense de Madrid (UCM) Dirección General de Investigación Científica y Técnica (DGICYT), España Ministerio de Economía y Competitividad (MINECO), España Depto. de Física de la Tierra y Astrofísica Fac. de Ciencias Físicas TRUE pub 2023-06-20T20:08:35Z 2023-06-20T20:08:35Z 1995-12 journal article https://hdl.handle.net/20.500.14352/59662 0365-0138 eng PB91-0348 open access application/pdf EDP Sciences