Reference : Hot and cool: two emission-line stars with constrasting behaviours in the same XMM-Ne...
Scientific journals : Article
Physical, chemical, mathematical & earth Sciences : Space science, astronomy & astrophysics
http://hdl.handle.net/2268/29457
Hot and cool: two emission-line stars with constrasting behaviours in the same XMM-Newton field
English
Nazé, Yaël mailto [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique observationnelle (sol et espace) >]
Rauw, Grégor mailto [Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Groupe d'astrophysique des hautes énergies (GAPHE) - Sciences spatiales >]
Ud-Doula, A. [Department of Physics, Morrisville State College, Morrisville, NY 13408, USA]
1-Feb-2010
Astronomy and Astrophysics
510
A59
Yes
International
[en] X-rays: stars ; stars: early-type ; stars: individual: 1RXS J171502.4-333344 ; stars: individual: HD 155806 ; stars: emission-line ; Be ; X-rays: individuals: HD 155889
[en] High-energy emissions are good indicators of peculiar behaviours in stars. We have therefore obtained an XMM-Newton observation of HD 155806 and 1RXS J171502.4-333344, and derived their spectral properties for the first time. The X-ray spectrum of HD 155806 appears soft, even slightly softer than usual for O-type stars (as shown by a comparison with the O9 star HD 155889 in the same XMM-Newton field). It is well-fitted with a two-component thermal model with low temperatures (0.2 and 0.6 keV), and it shows no overluminosity (log[L_X/L_BOL] = -6.75). The high-resolution spectrum, though noisy, reveals a few broad, symmetric X-ray lines (FWHMË 2500 km s[SUP]-1[/SUP]). The X-ray emission is compatible with the wind-shock model and therefore appears unaffected by the putative dense equatorial regions at the origin of the Oe classification. 1RXS J171502.4-333344 is a nearby flaring source of moderate X-ray luminosity (log[L_X/L_BOL] = -3), with a soft thermal spectrum composed of narrow lines and presenting a larger abundance of elements (e.g. Ne) with a high first ionization potential (FIP) compared to lower-FIP elements. All the evidence indicates a coronal origin for the X-ray emission, in agreement with the dMe classification of this source. Based on observations collected with XMM-Newton, an ESA Science Mission with instruments and contributions directly funded by ESA Member States and the USA (NASA).Research Associate FNRS.
http://hdl.handle.net/2268/29457
10.1051/0004-6361/200913118
http://adsabs.harvard.edu/abs/2010A%26A...510A..59N
http://de.arxiv.org/abs/0912.0379

File(s) associated to this reference

Fulltext file(s):

FileCommentaryVersionSizeAccess
Open access
0912_0379v3.pdfAuthor preprint337.54 kBView/Open

Bookmark and Share SFX Query

All documents in ORBi are protected by a user license.