Ultraviolet spectra of dwarf solar neighbourhood stars. I.
Doyle, J. G.; Butler, C. J.; Byrne, P. B.; Andrews, A. D.
United Kingdom
Abstract
Short-wavelength IUE spectra of three nearby M-type dwarfs are presented. Two of these stars, Gliese 867 A and AU Mic, are active UV Ceti flare stars and their UV spectra exhibit strong emission lines, characteristic of active chromospheres. The third star, Gliese 825, is a low-activity flare star and its spectrum reveals no chromospheric lines. A strong UV continuum exists in one of the spectra of Gliese 867 A and it is deduced that a flare took place during the exposure. A spectrum of the flare light is extracted and compared with the predictions of various flare models.