POLARIZED AND UNPOLARIZED DOUBLE PROMPT PHOTON PRODUCTION IN NEXT-TO-LEADING ORDER QCD

We calculate O(alpha(s)) corrections to inclusive and isolated double prompt photon production, both For the unpolarized case, and for longi tudinal polarization of the incoming hadrons. The calculation is perfo rmed using purely analytical techniques for the inclusive case, and a combination of analytical and Monte Carlo techniques to perform the ph ase space integration in the isolated case. A brief phenomenological s tudy is made of the process pp --> gamma gamma X at c.m.s. energies ap propriate for the RHIC heavy ion collider.