Using data from the Spitzer Survey of the SMC, we have discovered apopulation of 120 main sequence B stars with large 24 micron excesses.Optical spectroscopy and the IRAC SEDs demonstrate that they are notordinary YSOs or Be stars. We suggest instead that these objects maybe debris disks around massive main sequence stars. Confirmation ofthis hypothesis would provide one of the only ways to study theprocess of planet formation in a low-metallicity external galaxy. Wehave measured the mid-IR SED of the dust emission with IRSspectroscopy and determined that both cold and warm dust is present.We now propose PACS photometry at 70 microns to unambiguously separatethe dust into its warm (and therefore circumstellar) and cold(possibly interstellar) components. These data will enable us todetermine how much of the dust is warm and better constrain thetemperature distribution; any targets with substantial amounts of warmdust are almost certainly debris disks. If the B stars do indeed hostdebris disks, they provide perhaps the only plausible method forconstraining planet formation in an external galaxy for theforeseeable future.
Publication
Dusty OB Stars in the Small Magellanic Cloud. II. Extragalactic Disks or Examples of the Pleiades Phenomenon? | Adams Joshua J. et al. | The Astrophysical Journal Volume 771 Issue 2 article id. 112 23 pp. (2013). | 771 | 10.1088\\/0004-637X\\/771\\/2\\/112 | 2013ApJ...771..112A | http://adsabs.harvard.edu/abs/2013ApJ...771..112A
Instrument
PACS_PacsPhoto_largeScan
Temporal Coverage
2011-02-25T10:19:23Z/2011-07-23T21:36:29Z
Version
SPG v14.2.0
Mission Description
Herschel was launched on 14 May 2009! It is the fourth cornerstone mission in the ESA science programme. With a 3.5 m Cassegrain telescope it is the largest space telescope ever launched. It is performing photometry and spectroscopy in approximately the 55-671 µm range, bridging the gap between earlier infrared space missions and groundbased facilities.
European Space Agency, simon et al., 2012, 'A Population of Dusty B Stars in the SMC: The First Extragalactic Debris DisksquestionMark', SPG v14.2.0, European Space Agency, https://doi.org/10.5270/esa-rl2nm1z