To record such data, photographically suitable light sources linked to the hydrodynamic phenomena and cameras capable of resolving emall fractions of a microsecond have to be available. The light sources were provided for by the light radiated by the case of the device when heated by the shock wave, At both the mogiiiiien ::-. four LASL Model 100 streaking cameras and one L Model 6 framing camera were employed, Each of the Model 100 cameras photographed all the case shots; the Model 6 was directed at the device end-on and was employed for qualitative reasons only. isfactory pictures were obtained from the detonation of device, Indications are that though allthe cameras perrormed properly, a local heavy rainstorm between the bunker and the zero site cut the light transmission down to essentially zero. As a result no streaks were evident and all that was recorded by the Model 100 cameras was the fireball as it swept by the field of view, The Model 6 shows a faint glowing (Teller Light?) of about 11 microseconds duration and then a samewhat brighter glow growing in size about 40 microseconds later. 2.2.4 Program 24, External Neutron Measurements The object of Program 24 was to measure the energy spectrum of neutrons emanating from PG 2~-<<. of about 2 per cent should be An energy resolution ed for the (d,t) peak. Neutrons from the device coming down the Tenex pipe strike two radiators, Recoil protons from (n,p) collisions in the radiators are detected im nuclear emulsions. Measurements of proton rangea in emulsion yield proton energies, from which the neutron energies may be determined, The signal-to-noise ratio in the exposed plates is good. The single grain background is small, indicating a negligible exposure to gammas and electrons. Under a magnification of 100Ux, there is ebout 1 recoil proton from fission events per field of view and about 1 recoil proton from the (d,t) reaction per 20 fields of view. When corrections are made for engles of observation, solid angle, radiator thickness and the (n,p) cross-section, the resulting neutron energy spectrum shows a peak at 14 Mev, super-imposed on a fission spectrum. The (d,t) peak has about one-fourth of the area of the fission spectrum, There is a noticeable tail of the peak toward the low energy side which would indicate a contribution of scattered 14 Mev neutrons Coplegsnog LANL, J-Div, 3h -