VI photometry of Collinder 121

We present a VI photometric catalogue towards the open cluster Cr 121. XMM-Newton and ROSAT data are used to discover a low-mass pre-main sequence (PMS) along this sightline. de...本研究针对疏散星团Cr 121发布了一套VI测光星表。研究利用XMM-牛顿望远镜（XMM-Newton）与伦琴卫星（ROSAT）的观测数据，沿该视线方向发现了一颗低质量主序前恒星（PMS）。de...