Monoceros R2 Cloud Chandra X-Ray Point Source Catalog

With a deep exposure of ~ 100 ks, the authors detected 368 X-ray sources, ~80% of which were identified with near-infrared (NIR) counterparts. They systematically analyzed the spectra and time variability of most of the X-ray emitting sources and provide a comprehensive X-ray source catalog for the first time.

Using the J-, H- and K-bands magnitudes of the NIR counterparts, they have estimated the evolutionary phase, classical T Tauri (CTT) stars and weak-lined T Tauri (WTT) stars, and the masses of the X-ray emitting sources, and have analyzed their X-ray properties as a function of age and mass. They found a marginal hint that CTT stars have a slightly higher temperature (2.4 keV) that of WTT stars (2.0 keV). A significant fraction of the high- and intermediate-mass sources have time variability and high plasma temperatures (2.7 keV) simailar to those of the low-mass stars (2.0 keV).