Please use this identifier to cite or link to this item:
|Title:||X-ray emission from a brown dwarf in the Pleiades|
|Authors:||Briggs, K. R.|
Pye, J. P.
|Publisher:||Oxford University Press (OUP), Royal Astronomical Society|
|Citation:||Monthly Notices of the Royal Astronomical Society, 2004, 353 (2), pp.673-680|
|Abstract:||We report on the first detection of X-ray emission from a brown dwarf in the Pleiades, the M7-type Roque 14, obtained using the EPIC detectors on XMM–Newton. This is the first X-ray detection of a brown dwarf intermediate in age between ≈12 and ≈320 Myr. The emission appears persistent, although we cannot rule out flare-like behaviour with a decay time-scale >4 ks. The time-averaged X-ray luminosity of LX≈ 3.3 ± 0.8 × 1027 erg s−1 and its ratios with the bolometric (LX/Lbol≈ 10−3.05) and Hα (LX/LHα≈ 4.0) luminosities suggest magnetic activity similar to that of active main-sequence M dwarfs, such as the M7 old-disc star VB 8, although the suspected binary nature of Roque 14 merits further attention. No emission is detected from four proposed later-type Pleiades brown dwarfs, with upper limits to LX in the range 2.1–3.8 × 1027 erg s−1 and to log (LX/Lbol) in the range −3.10 to −2.91.|
|Rights:||Archived with reference to SHERPA/RoMEO and publisher website. This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2004 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.|
|Appears in Collections:||Published Articles, Dept. of Physics and Astronomy|
Files in This Item:
|MNRAS-2004-Briggs-673-80.pdf||Publisher version||224.41 kB||Adobe PDF||View/Open|
Items in LRA are protected by copyright, with all rights reserved, unless otherwise indicated.