First X-ray observation of a new microquasar with unprecedented massive outflows

IGR J21247+5058 is a new hard Xray source in the Galactic plane, coincidentwith the core of the double radio source 4C 50.55. Our optical observations showthat the counterpart of the radio core is a F9V star, displaying absorptionlines with velocity shifts typical of an Xray binary. New observations are inprogress. The unprecedented property of this microquasar is the presence of ahighly variable massive outflow. We propose XMMNewton observations to confirmthe proposed association between the Xray source and the core of 4C 50.55, lookfor eventual Xray emission from the radio lobes, obtain a detailed spectrum ofthe source to derive physical parameters (hydrogen column density, presence ofiron or other eventual lines), and finally look for QPOs and other variability. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]