A dataset provided by the European Space Agency

Name OT2_briaz_5
Title Brown Dwraf Disc Fraction at Ages of ~30-50 Myr
URL

http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342265503&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342265504&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342265505&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342265506&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342265507&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342265508&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342265620&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342265621&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342265622&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342265623&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342265624&instrument_name=PACS&product_level=LEVEL0&compress=true
...
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342265625&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342270969&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342270970&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342270971&instrument_name=PACS&product_level=LEVEL0&compress=true
http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342270972&instrument_name=PACS&product_level=LEVEL0&compress=true

DOI 10.5270/esa-90me0pq
Author riaz, b.
Description We propose to determine the brown dwarf disc fraction at ages of ~30-50 Myr. A comparison of the disc frequencies for stars and brown dwarfs shows very different trends with age. For the solar-type stars, optically thick primordial discs are virtually non-existent by an age of ~10 Myr. At ages >10 Myr, the inner disc material is significantly dissipated, and the discs have made a transition to the debris phase. In comparison, brown dwarf discs at ~10 Myr exhibit strong excess emission in the Spitzer-IRS 5-35m spectrum, and also show strong excesses at Spitzer 70m. The mid-infrared colors for these ~10 Myr old discs are found to be similar to the young optically thick discs in the 3 Myr old Orionis cluster, which indicates that these are still in their primordial phase. Thus no clear transition from a primordial to a debris phase is observed for the brown dwarf discs even at 10 Myr ages, unlike the higher mass stars. Furthermore, we find an increase in the brown dwarf disc frequency by a factor of ~2 between 5 and 10 Myr. We propose to observe with Herschel-PACS a sample of all spectroscopically conrmed brown dwarfs in clusters at ages of 30-50 Myr. At present, PACS is the only instrument with the required high sensitivities to observe brown dwarf discs at these ages. Obtaining data for brown dwarfs at ages older than 10 Myr will be important to map the evolution of brown dwarf discs over a wider age range, and to determine if the brown dwarf disc decay time scale is longer than that observed for the earlier-type stars.
Publication A Herschel PACS survey of brown dwarfs in IC 2391: limits on primordial and debris disc fractions . Riaz B. et al. . Monthly Notices of the Royal Astronomical Society, Volume 442, Issue 4, p.3065-3072 . 442 . 10.1093\/mnras\/stu1054 . 2014MNRAS.442.3065R ,
Instrument PACS_PacsPhoto_largeScan
Temporal Coverage 2013-02-20T06:59:22Z/2013-04-27T07:49:32Z
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 ┬Ám range, bridging the gap between earlier infrared space missions and groundbased facilities.
Creator Contact https://support.cosmos.esa.int/herschel/
Date Published 2013-10-27T07:22:26Z
Publisher And Registrant European Space Agency
Credit Guidelines European Space Agency, 2013-10-27T07:22:26Z, OT2_briaz_5, SPG v14.2.0. https://doi.org/10.5270/esa-90me0pq