J. Jolie et M. Bertschy, A TUNABLE MONOCHROMATIC GAMMA-RAY SOURCE .1. CONCEPT OF THE SOURCE, Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms, 95(3), 1995, pp. 431-436
By combining a curved-crystal spectrometer, operated in Cauchois geome
try, with a broad gamma-ray source with a continuous energy spectrum,
it is possible to construct a tunable gamma-ray source from which mono
chromatic gamma-ray beams with small divergence and energies ranging f
rom a few tens of keV up to a few MeV can be obtained.