Peculiar classified Wolf-Rayet stars, HD 90657 and HD 117688

Abstract

Spectral observations of Wolf-Rayet stars HD 90657 and HD 117688 were made at the Cerro Tololo Interamerican Observatory, in Chile. These stars have been classified by earlier authors as intermediate objects between the two sequences of W-R stars, presenting in their spectra lines of both carbón and nitrogen. However, our observations do not confirm this classification, the observed spectra look like “normal” WN stars. In addition, HD 90657, earlier classified as WN4—C -J- OB, shows variations of radial velocity of the order of 130 km/s and variations of type V/R in the shape of the emission lines.