ar X iv : a st ro - p h / 01 04 19 0 v 2 1 4 A pr 2 00 1 Chandra Observation of the ρ Oph Cloud
نویسندگان
چکیده
We observed a 17×17 region of the ρ Oph molecular cloud, using the ACIS-I array onboard the Chandra X-ray Observatory (CXO). A 100-ks exposure observation revealed ∼ 100 X-ray sources above the detection limit of ∼ 10 ergs s. About 2/3 of the X-ray sources are identified with an optical and/or infrared counterpart, including significant numbers of Class I, II and III sources and a few brown dwarfs. The X-ray detection rate of Class I sources is a surprisingly high 70 %. Many X-ray flares, possibly due to the magnetic activity, are found from all of the classes. We make systematic spectral studies of the quiescent and flare X-rays for all the X-ray sources. The X-ray temperatures and absorptions of Class I sources are generally larger than those of Class II and III sources. Also X-ray flares from Class I sources show slightly higher duty ratio, temperature, and luminosity, than those of more evolved classes. We further give brief results on brown dwarfs, sources in a younger phase than Class I, unclassified, and unidentified sources. Details for several selected young stellar objects, including the first detection of a neutral iron line (6.4 keV) from a Class I source (YLW 16A), are separately addressed. 1CREST, Japan Science and Technology Corporation (JST), 4-1-8 Honmachi, Kawaguchi, Saitama, 332-0012, Japan
منابع مشابه
ar X iv : a st ro - p h / 01 04 19 0 v 1 1 1 A pr 2 00 1 Chandra Observation of the ρ Oph Cloud
We observed a 17×17 region of the ρ Oph molecular cloud, using the ACIS-I array onboard the Chandra X-ray Observatory (CXO). A 100-ks exposure observation revealed ∼ hundred X-ray sources above the detection limit of ∼ 10 ergs s. About 2/3 of the X-ray sources are identified to an optical and/or infrared counterpart, including significant numbers of class I, II and III sources and a few brown d...
متن کاملar X iv : a st ro - p h / 01 04 19 0 v 3 7 M ay 2 00 1 Chandra Observation of the ρ Oph Cloud
We observed a 17′×17′ region of the ρ Oph molecular cloud, using the ACIS-I array onboard the Chandra X-ray Observatory (CXO). A 100-ks exposure observation revealed ∼ 100 X-ray sources above the detection limit of ∼ 10 ergs s. About 2/3 of the X-ray sources are identified with an optical and/or infrared counterpart, including significant numbers of Class I, II and III sources and a few brown d...
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