flim (MOHAWK) Vv Project 21.4 ~ External Neutron Flux Measurements ~ N. Bonner Three sets of external Detectey were placed on the northwest tip of Eberiry end at 1300 feet from spaced 150 feet apart. : (Mohawk). Each set of detectors were anothe>three sets of detectors wereByee? on the southeast tip of Rojoru at a distance of 2,500 feet from a. This set of detectors also were spaced 150 feet apart, e detectors were a sample of arsenic and a zirconium sample sealed in a boron 10 shield, It was hoped that one could determine the number of fest neutrons by observing the (n,2n) reaction on these samples, The set of samples placed on Rojoru were recovered on July 8, and were sent back to Livermore on July 10 for counting. The set of samples on the northwest tip of Eberiru could not be recovered at this time since the cable had been broken. The set of samples on Eberiru Ky recovered on July 17 and sent back to Livermore on Flyaway 1 The flux at 1 meter from the device axis resulting from neutrons emitted normal to the exis was calculated using an air mean free path of 190 yards for the Zr and 195 yards for the arsenic. | 1 6 Bren tse ate, we oy Cen ~ aa _ él _ aE G