Wolf-Rayet Stars. II. The Infrared Spectrum

The infrared spectrum of bright WoIf-Rayet stars from 8000 to 10900 has been scanned with a photoelectric spectrum scanner with a resolution of 10 A. The WC stars show a well-developed spectrum of C iii and C iv, whereas the WN stars show no identifiable lines of the nitrogen ions. Both sequences have strong lines of He I and He ii. The strongest lines of each sequence occur very close together (i.e., C iii X 9710 for WC's and He ii X 10124 for WN's) and would enable the easy separation of WoIf-Rayet stars into the carbon and nitrogen sequences by means of narrow-band photometry.