The geometry, kinematics, and operation of the curved crystalgamma-ray spectrometer are briefly described. The effect of a recentlydiscovered systematic non-linearity is discussed in some detail. Anew calibration of the instrument and the means taken to correct forthe non-linearity are described. Error-contributing factors are analyzed,and their contributions to the final error are estimated. The threeprincipal components of the observed line profile are discussed.
A new measurement of the annihilation radiation is reported. Therelation of this measurement to the determination of the mass of thepositron is discussed. Measurements of the wavelength of the 411 Kevgamma-ray line following decay of Au198 are given. Wavelengths ofsixteen gamma-ray lines following decay of Ta182 are tabulated. Theformulation of an energy level scheme for its daughter W182 is discussed.
