ASTRONOMY AND ASTROPHYSICS Spectroscopy of HD 4004 . Correlated profile variations ? ?
نویسنده
چکیده
We present results of detailed analysis of spectral variability observed in the optical spectrum (λλ 4350–5700 Å) of HD 4004 (WR 1). Basing on data obtained during spectroscopic monitoring of this object in three nights in September 1994, and six nights in November 1995 we show that the variations observed in He ii lines λ 4542, 4686, 4860 and 5411 are very similar and well correlated. We also show that the amount of variability in these lines is identical. We provide evidence, however, that the variations as observed in those He ii show also noticeable differences. The projected velocities of perturbations exposed on He ii emission line profiles do not scale with line width (FWHM). This means that the factor responsible for the observed profile variations is not coupled with the wind and its velocity law. Based on our results we argue for two-component (fast-slow) wind model of HD 4004.
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