The flare activity of V390 Aur: First results of an international collaboration

V390 Aur is classified as a G8 spectral class active single giant by Fekel and Marshall (1991). Multi-site cooperative high-speed photoelectric monitoring was carried out for it in the period 1998-2003 as part of a program developed in Bulgaria recently to study chromospherically active evolved stars. Astronomers from Greece and Ukraine joined the flare activity study of V390 Aur in 2000. As a result, several flares with a duration from seconds to minutes were detected on this star at 3 observatories. Taking into account all the events detected, the flare rate of the star is estimated to 0.205 flares per hour. Comparison with the active dwarfs AD Leo and EV Lac indicates that the flare rate of V390 Aur is lower than that of AD Leo but comparable with the well-known flare star EV Lac. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)