The circumstellar gas around beta Pictoris. VIII. Evidence for a clumpy structure of the infalling gas.
Abstract
In a recent paper, the variable and redshifted circumstellar lines of ionized elements in the UV spectrum of Beta Pictoris were studied. The Al III doublet has been investigated, using both archival and recent IUE spectra of Beta Pic. This larger set of data is used to derive some general characteristics of the variable Al III lines. In particular, it seems that variable lines are frequently observed, more often than for Ca II, and that high-infall-velocity (400 km/s) Al III ions are either less frequent than lower-infall-velocity (100 km/s) ones or more quickly decelerated. Moreover, it is shown that, at least in one case, this high velocity gas is probalby clumped in space with a less than 40 percent of the stellar surface projected extension. These new results are well explained by the infalling-evaporating large solid bodies scenario that has been suggested in previous papers.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- May 1989
- Bibcode:
- 1989A&A...215L...5L
- Keywords:
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- A Stars;
- Stellar Envelopes;
- Stellar Spectrophotometry;
- Ultraviolet Spectra;
- Absorption Spectra;
- Iue;
- Red Shift;
- Stellar Spectra;
- Astrophysics