Stellar activity in barium stars .1. Analysis of H-lines and K-lines CA-II-lines in 10 barium stars
High dispersion spectra have been obtained in order to study the activity level of ten barium stars by means of the Ca II H and K emission flux, looking for a relation between barium intensity index and activity. Absolute magnitudes obtained from the Wilson-Bappu relationship disagree, in some cases...
| Autores: | , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 1992 |
| País: | España |
| Institución: | Universidad Complutense de Madrid (UCM) |
| Repositorio: | Docta Complutense |
| Idioma: | inglés |
| OAI Identifier: | oai:docta.ucm.es:20.500.14352/59665 |
| Acceso en línea: | https://hdl.handle.net/20.500.14352/59665 |
| Access Level: | acceso abierto |
| Palabra clave: | 52 Mass-loss Emission Astrofísica Astronomía (Física) |
| Sumario: | High dispersion spectra have been obtained in order to study the activity level of ten barium stars by means of the Ca II H and K emission flux, looking for a relation between barium intensity index and activity. Absolute magnitudes obtained from the Wilson-Bappu relationship disagree, in some cases, with the magnitudes computed from parallaxes, but this fact is not due to barium nature. Total emission fluxes, F(H + K) or R_HK index, plotted versus effective temperature show a distribution similar to that of cool giant stars. The asymmetry of K emission line, [F(K_2ν)/F(K_2r)], has been analyzed in relation with effective temperature, in this sense barium stars behave as expected of late-type giants with the only exception of two stars. |
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