Coordinated ultraviolet and Hα spectroscopy of bright O-type stars.

Details Coordinated ultraviolet and Hα spectroscopy of bright O-type stars. Coordinated ultraviolet and Hα spectroscopy of bright O-type stars.

Nov 1997

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997a%26a...327..281k&link_type=abstract

Astronomy and Astrophysics, v.327, p.281-298

Astronomy and Astrophysics

Astrophysics

76

Stars: Early-Type, Stars: Magnetic Fields, Stars: Mass Loss, Stars: Rotation, Ultraviolet: Stars

Scientific paper

As part of our search for the origin of stellar-wind variability, we have conducted simultaneous ultraviolet and Hα spectroscopy of a number of bright O stars. The observed changes in the Hα line occur at low velocity (0-0.2vinfinity_) on timescales that are characteristic of the development and evolution of discrete absorption components (DACs) in UV resonance lines. In some cases, a direct relationship is found between the changes occuring in the Hα line and subsequent variations in the high-velocity stellar wind. On the basis of this relationship, the appearance of a DAC in the UV resonance lines can be predicted from (ground-based) Hα observations. These observations show that the stellar wind is variable down to regions close to or at the stellar surface. Since the timescales of the variations can be related to the rotation periods of the stars in our sample, we propose that a stellar magnetic field (which remains undetected) might play an important role in affecting the base of the stellar wind. The observed variations are interpreted in terms of corotating wind structures, similar to the Corotating Interaction Region (CIR) model proposed by Mullan (1986A&A...165..157M) and recently simulated by Cranmer & Owocki (1996ApJ...462..469C).

Affiliated with

Also associated with

No associations

Rating

Coordinated ultraviolet and Hα spectroscopy of bright O-type stars. does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Coordinated ultraviolet and Hα spectroscopy of bright O-type stars., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Coordinated ultraviolet and Hα spectroscopy of bright O-type stars. will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1682315