Chapter 1.1 OBJECTIVES | INTRODUCTION The principal technical objectives of this project included the fol- lowing: 1. To obtain the necessary data~~-utilizing chemical, radiochemical, physical, and nuclear-physical techniques on close~in nuclear debris--~to establish reference or calibration points for analyses, using the same techniques, of debris from nuclear explosions of unknown origin, composi~ tion, and design. 2+ To compare analyses on samples collected close-in to the detona- tion with those obtained at great distances, in order to study variability of debris composition with time and distance from detonation site. 3. To test the Squeegee gas~sampling device under full-scale operational conditions. 1.2 BACKGROUND This experiment was an extension of a program established to monitor all United States nuclear explosions, in order to establish calibration or reference points based on analyses of air~borne nuclear debris collected under the best possible conditions. This program, under Head- quarters, United States Air Force, Washington 25, D. Cc. (AFOAT~1), had actively participated in Operations Sandstone, Ranger, Greenhouse, BusterJangle, Tumbler-Snapper, Ivy, and Upshot-Knothole. Data based on debris analysis from Trinity, with specific reference to capture-to-fission ratios and bomb efficiency, suggested the possibility that these types of analyses might be extended to give more diagnos~ tic information about the source than had been thought possible. Therefore, serious efforts were expended in applying micro- and macroradiochemical techniques, and other specialized analytical method to air-borne nuclear debris. These analyses yielded useful diagnostic in- formation. It became possible to determine nuclearefficiency. | — __ _fand other use- | ful information required in a detection and analysis system. A condensed review of results obtained using the techniques described here during Operations Sandstone, Ranger, Greenhouse, an Particularly---Buster-Jangle, Tumbler-Snapper, and Upshot~Knothole appear in| .)publications (References 2, 18, and 19).