Quiescent X-ray emission from the M9 dwarf LHS 2065
arXiv:0806.3863 · doi:10.1051/0004-6361:200810142
Abstract
We investigate an archival XMM-Newton observation of LHS 2065, an ultracool dwarf with spectral type M9. We clearly detect LHS 2065 at soft X-ray energies in less than 1 h effective exposure time above the 3 sigma level with the PN and MOS1 detector. No flare signatures are present and we attribute the X-ray detection to quasi-quiescent activity. From the PN data we derive an X-ray luminosity of L_x = 2.2 +/- 0.7 x 10^26 erg/s in the 0.3-0.8 keV band, the corresponding activity level of log L_x/L_bol = -3.7 points to a rather active star. Indications for minor variability and possible accompanying spectral changes are present, however the short exposure time and poor data quality prevents a more detailed analysis. LHS 2065 is one of the coolest and least massive stars that emits X-rays at detectable levels in quasi-quiescence, implying the existence of a corona.
accepted by A&A, 3 pages, 2 figures (research note)
References in corpus (3)
Cited by in corpus (8)
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