Volume 413, Number 2, January II 2004
|Page(s)||681 - 691|
|Section||Stellar structure and evolution|
|Published online||18 December 2003|
The spatial structure of the β Pictoris gas disk *
Stockholm Observatory, AlbaNova University Centre, 106 91 Stockholm, Sweden e-mail: email@example.com, firstname.lastname@example.org
2 ESA/ESTEC, PO Box 299, 2200 AG Noordwijk, The Netherlands e-mail: Malcolm.Fridlund@esa.int
Corresponding author: A. Brandeker, email@example.com
Accepted: 7 October 2003
We have used VLT/UVES to spatially resolve the gas disk of β Pictoris. 88 extended emission lines are observed, with the brightest coming from Fe I, Na I and Ca II. The extent of the gas disk is much larger than previously anticipated; we trace Na I radially from 13 AU out to 323 AU and Ca II to heights of 77 AU above the disk plane, both to the limits of our observations. The degree of flaring is significantly larger for the gas disk than the dust disk. A strong NE/SW brightness asymmetry is observed, with the SW emission being abruptly truncated at 150–200 AU. The inner gas disk is tilted about 5° with respect to the outer disk, similar to the appearance of the disk in light scattered from dust. We show that most, perhaps all, of the Na I column density seen in the “stable” component of absorption, comes from the extended disk. Finally, we discuss the effects of radiation pressure in the extended gas disk and show that the assumption of hydrogen, in whatever form, as a braking agent is inconsistent with observations.
Key words: stars: individual: β Pictoris / stars: circumstellar matter / stars: planetary systems: formation / stars: planetary systems: protoplanetary disks
© ESO, 2004
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.