Jets from protostars: a new class of astronomical X-ray sources

Following our detection for the first time of Xray emission from ashock associated with a protostellar jet (from L1551 IRS5) we proposeto observe with XMM two shocks associated with protostellar jets forwhich previous (unreported) evidence of associated Xray emission ispresent. The collecting area of XMM will allow good S/N Xray spectrato be collected, allowing to determine whether Xray emission is ageneral characteristic of protostellar jets as a class and to studythe physical conditions in the two targets, also assessing theirinfluence on the conditions of e.g. the protostellar accretion disk. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]