——— (FLATHEAD) Project 8.5 = Airborne High Resolution Spectral Analysis = R, Zirkind Ob jective To determine the radiant power of a function of wavelength and the fireball olor temperature as seen from an airborne station. These objectives were to be accomplished by deter= mining the atmospheric attenuation by an independent measurement and correcting the power received at the instrument station aboard the air= craft. Instrumentation “ The spectral distribution of the radiant power is obtained from a medium quartz Hilger spectrometer. The spectrum is sampled in narrow bands by photocells in the visible region and PbS cells in the infra-red, The electrical signal is then recorded on an Ampex 81, tape recorder, with a resolution time of 150~sec. The transmission measurement is accomplished by beaming a pulsed light signal of known output and spectral distribution from a fixed point on the ground towards the aircraft. The attenuated beam is received by a detector in the aircraft and recorded on a Heiland recorder, The detector consists of two filtered photo-multiplier tubes sampling two spectral regions, (1) .3-.55 microns and (2) .6-1.05 microns. In addition, a quartz filtered calorimeter, 22 degrees field of view, is utilized to measure the approximate radiant exposure received at the spec= trometer. Results The aircraft was approximately 1950 feet beyond intended location at COPIED/DQE LANL RC Planned position was on an out-bound heading of 287°9T having a mo time zero. - 64 -

Select target paragraph3