Discovery and disentangling of multi-mode delta-Sct pulsations in the eclipsing binary V994 Her

Abstract

Accurate and extensive photoelectric photometry has been obtained of V994 Her which was discovered as an eclipsing binary by Hipparcos satellite. A marked pulsation activity is evident in the light-curve, with periods 0.152100488, 0.116836079 and 0.09466580 day that appears to be the contemporanous presence of fundamental, first and second overtone periods of a multi-mode delta-Sct pulsation. The latter is observed to remain stable in amplitude and phase over the whole observaing campaign that lasted between June 10, 2002 and July 15, 2004.