An Unprecedented Change in the Spectrum of S Doradus: As Cool as It Gets

Details An Unprecedented Change in the Spectrum of S Doradus: As Cool as It Gets An Unprecedented Change in the Spectrum of S Doradus: As Cool as It Gets

Feb 2000

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2000pasp..112..144m&link_type=abstract

The Publications of the Astronomical Society of the Pacific, Volume 112, Issue 768, pp. 144-147.

Other

17

Galaxies: Magellanic Clouds, Stars: Early-Type, Stars: Evolution, Stars: Variables: Other

Scientific paper

Recent observations of S Doradus, the archetype of luminous blue variables (LBVs), reveal that the star's optical spectrum now resembles an F-type supergiant, with a rich complex of absorption lines. Despite nearly 50 years of spectroscopic monitoring, such a spectrum has never before been seen for S Dor despite numerous occasions when the star was equally bright. However, such F-type spectra have been seen in other LBVs, including Var B in M33 during a recent outburst, and in η Carina during an outburst in 1893. The singly ionized metal lines arise in a layer moving away from the star (toward us) at 50 km s-1, consistent with the lines forming in a ``pseudophotosphere'' originating in the stellar wind. The temperature suggested by the F-type spectrum is as cool as an LBV can get. Our CCD UBV photometry shows that the star has brightened only 0.3 mag in V since 1996, at which time it showed an emission-line spectrum characteristic of LBVs at minimum. The dereddened B-V color is consistent with an effective temperature suggested by the spectrum (7500 K), but there is a pronounced UV excess as evidenced by U-B. Why the behavior of S Dor has suddenly changed remains a mystery.

Affiliated with

Also associated with

No associations

Rating

An Unprecedented Change in the Spectrum of S Doradus: As Cool as It Gets 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 An Unprecedented Change in the Spectrum of S Doradus: As Cool as It Gets, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and An Unprecedented Change in the Spectrum of S Doradus: As Cool as It Gets will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1801332