Temperature and gravity of the pulsating extreme helium star LSS 3184 (BX Cir) through its pulsation cycle

  title={Temperature and gravity of the pulsating extreme helium star LSS 3184 (BX Cir) through its pulsation cycle},
  author={Vincent M. Woolf and C. Simon Jeffery},
  journal={Astronomy and Astrophysics},
We report the analysis of optical spectra of the extreme helium star LSS 3184 (BX Cir) to determine its effective temperature and gravity throughout its pulsation cycle. The spectra were also used to measure its chemical abundances. We report rest gravity, log g = 3.38 +/- 0.02, and a chemical abundance mixture consistent with those reported earlier in a study using an optical spectrum with lower spectral resolution and a lower signal to noise ratio. Our analysis decreases the upper limit for… 

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