ASTRONOMY AND ASTROPHYSICS Circumstellar disk variations around β Pictoris
نویسنده
چکیده
We present high resolution spectral observations of the absorption lines of Ca II and Na I associated with the circumstellar disk surrounding the starβ Pictoris. The observations were taken over a four night period in January 1996 and reveal substantial profile variability between successive nights. High velocity absorption features at velocities of +58 km s−1 were observed in the Ca II data, but were not present in the Na I profiles. An unusually high Ca II: Na I ratio of∼ 150:1 was found for the central, stable V = +22 km s−1 component.
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