HST - GHRS observations of candidate β Pictoris - like circumstellar gaseous disks ?
نویسنده
چکیده
We present HST-GHRS observations of four stars in search of β Pictoris-like circumstellar gaseous disks. We detected gas around HR 10, HR 2174 and 51 Oph at large distances from the stars; this gas is circumstellar since the absorption lines from very excited levels require densities incompatible with those found in the diffuse interstellar medium. The shape of the lines and the Mg ii doublet ratio give evidence that clumpy gas is continuously falling onto these stars. Possible interpretations are discussed.
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