The ultraviolet spectra of 94 WR stars obtained from Vilspa IUE archive are used here to look for classification criteria in the UV region alone. We have tried to select as many single and SB1 type stars as possible in the Galaxy and the LMC to get the complete, flux-calibrated spectra between 1150 and 3250 Å. Altogether 56 (34 of WN and 22 of WC type) stars in the Galaxy and 38 (31 of WN and 7 of WC type) in the LMC were found, for which at least single SWP and LWR (or LWP) low resolution images are accessible – note that this is about one third of the number of known galactic and LMC WR stars. The set of stars we study is representative according to spectral subtype and brightness (it is almost complete to 12 magnitude for galactic stars). See Niedzielski & Rochowicz (1994) for the list of program stars and associated IUE images as well as for the details of reduction.To look for classification criteria of WR stars in the ultraviolet region we will use the equivalent width (EW) and line width (FWHM) data.
We summarize an analysis of low-resolution IUE archival data for galactic and LMC Wolf-Rayet stars. We examine the correlation between ionization potential with line-width (FWHM) constituting a sample of stars showing a well-defined UV ionization structure.
New spectroscopic and photometric observations of WR22 are presented. High signal-to-noise digital spectra with high dispersion are used to improve the parameters of the orbit (P = 80.31 ±0.01 d), formerly determined on the basis of photographic spectra only. The intrinsic photometric variability of WR22 and recent observations of the eclipse are also discussed.
Abstract.First results of an on-going search for Wolf-Rayet galaxies, based on new observations obtained with the Hobby Eberly Telescope (HET) and the Marcario Low Resolution Spectrograph (LORES), are presented. UM 456 and UM 594 have been found to be normal HII galaxies. New determinations of radial velocities have been given: UM 456 -Vr = 1702 ± 48 km s −1 UM 594 -Vr = 6540 ± 45 km s −1 . Independent estimates of distances, WR/(WR+O) ratios and oxygen to helium abundances ratios have been obtained.
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