The blue-shifted absorption component of the P-Cygni profile at He I A5876 in HD 152408 (08: ) has been found to be extremely broad, extending -1000 km sec-1 from the emission maximum. This unusual profile is probably due to overpopulation of the lower level of 5876, which permits it to form throughout a greater extent of the expanding atmosphere than most other lines. This observation confirms Hutchings' identification of very large velocities in the blue-violet spectrum of HD 152408, and in particular his interpretation of a similar feature at He I 3889, which is metastable. The A5876 profile in HD 152408 is compared to those in the similar but less extreme PCygni star HD 151804 (08 laf), and in the Wolf-Rayet star HD 151932 (WN7-A). The similarity between the absorption components in HD 152408 and the WN star is striking.
No takes yet. Share an insight, caveat, or question.
N. R. Walborn (1975) studied this question.