Magnetic OB stars, and normal B stars
Magnetically channeled wind-shock models are promising
(q 1 Ori C, perhaps t Sco): Schulz (2003) has shown that O
stars have these X-ray signatures for less than 1 million
years on the main sequence
Normal B stars (like b Cru, B0.5 IV and e CMa B2 II) have
very soft X-ray spectra and narrow lines: wind shocks if the
X-ray wind isnŐt moving very fast? Magnetically channeled
wind shocks if the shocks arenŐt very strong? Dynamo-
driven coronae if our understanding of dynamos is
incompleteÉ