Probing Class 0 Protostars with Hard X-rays virgulOMC2-3 Regionvirgul

Using ASCA, we have demonstrated the capability of hard Xrays to detect embedded protostars (Class Is). In this proposal we seek to detect youngest protostars, known as Class 0s. Our goals are: 1. To probe when a star begins to emit Xrays. 2. To probe the differences in Xrays between Class 0s and other phases of star formation (Class I, II, III). The OMC 2/3 region is the best target because: (i) The spatial density of the Class 0s is the highest known anywhere in the sky. (ii) The dust temperature gradient from the north (OMC3) to the south (OMC2) indicates a difference in evolutionary status. (iii) Recently, we detected diffuse hard Xrays (210 keV) near these Class 0s with ASCA. We need XMM to resolve the diffuse hard Xrays near the Class 0 objects truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]