Are the SCUBA deep survey sources starbursts or AGN

We propose to make 50 kilosecond images of two fields for which we have deep SCUBA 850 micron images which have revealed a large number of highly luminous dusty galaxies. These galaxies appear to be similar to IRASselectedUltraluminous objects, and if powered by starformation then a significant fraction of all stars ever formed formed in these sources. It is also possible however that these galaxies are are in fact examples of obscured AGN, as have been postulated to contribute a large fraction of the Xray background at high energies. The proposed observations will test which of truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]