Long-term chromospheric activity in southern M dwarfs: Gl 229 A and Gl 752 A

Дата и время публикации : 2010-11-04T12:32:18Z

Авторы публикации и институты :
Andrea P. Buccino
Rodrigo F. Díaz
María Luisa Luoni
Ximena Abrevaya
Pablo J. D. Mauas

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: Accepted for publication by Astronomical Journal (AJ)
Первичная категория: astro-ph.SR

Все категории : astro-ph.SR

Краткий обзор статьи: Several late-type stars present activity cycles similar to that of the Sun. However, these cycles have been mostly studied in F to K stars. Due to their small intrinsic brightness, M dwarfs are not usually the targets of long-term observational studies of stellar activity, and their long-term variability is generally not known. In this work, we study the long-term activity of two M dwarf stars: Gl 229 A (M1/2) and Gl 752 A (M2.5). We employ medium resolution echelle spectra obtained at the 2.15 m telescope at the Argentinian observatory CASLEO between the years 2000 and 2010 and photometric observations obtained from the ASAS database. We analyzed Ca II K line-core fluxes and the mean V magnitude with the Lomb-Scargle periodogram, and we obtain possible activity cycles of $sim$4 yr and $sim$7 yr for Gl 229 A and Gl 752 A respectively.

Category: Physics