ee Omen ae aN Ahme Se is Tarawa would be a better choice than Kusaie, and (c) technical considerations have resulted in the elimination of all other sites at tnis range. PROGRAM 8 This proposal has been approved by JTF 132. THERMAL RADIATION MEASUREMENTS Mucn of the prototype equipment planned for use in this program by tne Naval Research Laboratory was tested at Tumbler-Snapper. High- speed pnotocell circuits were built at NRL and operated successfully at Snapper. The bolometer chopper equipments used at Greenhouse were modified to give a smaller time constant and operated successfully at Nevada. Tne rebuilt nign-speed:spectrographs used at Greenhouse performed satisfactorily with a resolving time of 2psec. It is con= sidered tnat equipment to be used in this program performed very well at Nevada and few modifications will be required for Operation Ivy. An additional station nas been added to Project 8.1. That station will be on the coral head for King Shot and is required in order to increase the probability of obtaining the vital data as to total thermal radiation from that shot. The problem of cloud cover is a serious one, and tne likelihood of having a wisp of cloud between tae top of the fireball and tne detector is real. Since ‘the value of thermal data on tunis snot is very high, and another device may not be fired under these conditions for a long time, the extra insurance given by sucn a station is certainly worthwhile. At Mike Shot it is proposed to operate on Elugelab and at a Two 250=w, 110-w spotlights NS location as close to zero as feasible.