The extreme helium star BD-9 deg 4395

Details The extreme helium star BD-9 deg 4395 The extreme helium star BD-9 deg 4395

Jul 1992

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1992a%26a...260..133j&link_type=abstract

Astronomy and Astrophysics (ISSN 0004-6361), vol. 260, no. 1-2, p. 133-150.

Astronomy and Astrophysics

Astronomy

52

B Stars, Helium, Stellar Composition, Stellar Spectra, Ultraviolet Astronomy, Emission Spectra, Line Spectra

Scientific paper

Simultaneous optical and UV spectroscopy is used to investigate both the photospheric variations and emission-line behavior of the extreme helium star BD-9 deg 4395. The photospheric parameters of the star are rederived from the optical spectra by the method of fine analysis, on the basis of up-to-date atomic data and new line-blanketed model atmospheres. The principal results are: T(eff) = 22,700 K, log g = 2.55, n(H)/n(He) = 0.0015, and n(C)/n(He) = 0.0004. Assuming an He-shell model, a mass of about 0.7 solar mass is obtained. The emission-line spectrum which principally contains lines due to He I, C II, and Si II, is probably due to recombination in a shell, or extended atmosphere, with a temperature slightly below T(eff). Both nonvariable and variable components may be identified, and suggest substantial dynamical activity in the shell.

Affiliated with

Also associated with

No associations

Rating

The extreme helium star BD-9 deg 4395 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 The extreme helium star BD-9 deg 4395, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The extreme helium star BD-9 deg 4395 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1203075