Can accretion shocks of very-low-mass stars produce X-ray emissionquestionMark
收藏资源简介：
The accretion process in young stars produces intense Xrays. Verylowmassstars (VLMS) cannot have postshock hotter than 2MK, preventing any Xrayemission. Nonetheless 2 accreting VLMS showed Xrays from accretion shocks. Toconfirm or reject this finding we propose to observe 3 other accreting VLMS withXMM/EPIC (10ks for each target) to measure the plasma temperature, and hencedistinguish between Xrays due to corona or to accretion. AccretiondrivenXrays in VLMS would indicate postshocks hotter than 2MK, possible only ifaccretion velocity is higher than free fall velocity. Checking the hypothesis ofaccretiondriven Xrays in VLMS is fundamental to test whether anothermechanism, other than gravity, accelerates accreting material. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]
