Forming the first planetary systems: debris around Galactic thick disc stars
Abstract
The thick disc contains stars formed within the first Gyr of Galactic history, and little is known about their planetary systems. The Spitzer MIPS instrument was used to search 11 of the closest of these old low-metal stars for circumstellar debris, as a signpost that bodies at least as large as planetesimals were formed. A total of 22 thick disc stars has now been observed, after including archival data, but dust is not found in any of the systems. The data rule out a high incidence of debris among star systems from early in the Galaxy's formation. However, some stars of this very old population do host giant planets, at possibly more than the general incidence among low-metal Sun-like stars. As the Solar system contains gas giants but little cometary dust, the thick disc could host analogue systems that formed many Gyr before the Sun.
Additional Information
© 2010 The Authors. Journal compilation © 2010 RAS. Accepted 2010 August 18. Received 2010 August 13; in original form 2010 June 28. Article first published online: 7 Sep 2010. CKWS thanks STFC for a studentship, and JSG thanks STFC for a fellowship, in support of this work.Attached Files
Published - Sheehan2010p11762Mon_Not_R_Astron_Soc.pdf
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Additional details
- Eprint ID
- 20744
- Resolver ID
- CaltechAUTHORS:20101110-110930649
- Science and Technology Facilities Council (STFC)
- Created
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2010-11-11Created from EPrint's datestamp field
- Updated
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2021-11-09Created from EPrint's last_modified field
- Caltech groups
- Infrared Processing and Analysis Center (IPAC)