Abstract

New spectroscopic data of the peculiar interacting binary system W Serpentis in the region of H-alpha and H-beta are being reported, through the phase interval 0.95-0.16 p. We recognize the six sets of lines described by Sahade and Struve (1957). In addition to the Fe II concentration lines in the blue region, reported in earlier work, we find the presence of O I concentration in the red that confirms the existence of a low density region surrounding the system, as suggested by Sahade and Struve (1957). We confirm the difficult interpretation of features in the Mg II 4481 A region. We present radial velocities from He I for the first time.