We are using a Sm-Co based permanent magnet spectrometer to analyze Compton electrons ejected from a Be converter foil that is illuminated by a gamma-ray beam. The distance along the focal plane at which a mono-energetic electron beam entering the spectrometer will cross the focal plane is proportional to the square root of the electron momentum. This design achieves a very broad range of energies that are analyzed (from momentum of about 1 MeV/c up to 30 MeV/c) while maintaining good energy resolution (the electron momentum resolution is the larger of 0.1 MeV/c or 1% of the momentum). In addition this design has a fairly large acceptance. By restricting the angular acceptance of the spectrometer for the Compton electrons, incoming gamma ray energies and ejected electron momenta are simply related. The electron optical properties of this spectrometer are discussed as well as some aspects of the overall system design and testing.

Date Published: 22 December 1992
PDF: 9 pages
Proc. SPIE 1734, Gamma-Ray Detectors, (22 December 1992); doi: 10.1117/12.138599

Published in SPIE Proceedings Vol. 1734:
Gamma-Ray Detectors
Elena Aprile, Editor(s)