Development and Alignment of AN Automated Two Meter Bent-Crystal Spectrometer and its Application to the Study of Radiative Neutron Capture in AMERICIUM-241.

A two meter bent-quartz-crystal spectrometer in the Cauchois geometry has been developed and aligned. The (110) planes have been used in order to attain high resolution by avoiding the deformation of the reflecting planes under the bending stresses. Signals originating in the Germanium detector and digitized by a 8192 channel ADC were then compared with computer generated digital windows for the purpose of background suppression. The improved resolution and signal discrimination capability has been applied to the study of the complex gamma ray spectrum resulting from Am('241) (n,(gamma))Am('242) in an Americium target in the Livermore Pool Type Reactor through-tube with the spectrometer in the automatic mode of operation. The introductory section serves as a reasonably self contained treatment in modern notation for those who may be interested primarily in the use of bent crystal spectroscopy results, but desire some appreciation of the underlying theory.