1999A&A...350L..55K

Spectroscopic manifestations of the s-Cepheid EV Sct binarity are reported. All the lines in the spectrum of this faint Cepheid are strongly asymmetrical or even splitted indicating that this system consists of two components. Both components have close effective temperatures, the difference in the visual magnitudes seems to be not great. Together with the preliminary results of the frequency analysis based on the published photometrical data, this means that the secondary component is probably also situated within the instability strip, being a very short-period Cepheid (P≃1.2 day)