2003A&A...404..611K

Spectroscopic observations around the H_α line and BVR photometry of the eclipsing, short-period, RS CVn-type star ER Vul are presented. The solutions of new radial velocity and light curves yielded the following masses and radii of the components: M₁=1.16M_☉, M₂=1.05M_☉, R₁=1.25R_☉, R₂=1.12R_☉. The equatorial velocities corresponding to the measured rotational broadenings of the spectral lines are: V_eq¹=90km/s and V_eq²=80km/s. Their ratio is just equal to the ratio of the stellar radii. We detected excess emission in the H_α and CaI 6494 lines that changes during the orbital cycle. Our spectral data show the presence of absorbing matter around the mass center of the system.