Chandra observations of the ρ ophiuchi cloud

Abstract

Chandra observed two regions near the cores of the ρ Ophiuchi dark cloud. A 100-ks exposure for each observation revealed ∼ 200 X-ray sources above the detection limit of ∼ 1028 erg s-1. About 60% (110) are identified with an optical and/or infrared counterpart, including significant numbers of Class I sources and brown dwarfs. Three Class 0 candidates are newly discovered with the X-rays. Many X-ray flares, possibly due to the magnetic activity, are found from all of the Classes. We report the results of the systematic spectral and timing analysis on the quiescent and flare X-rays.