MONOENERGETIC BREMSSTRAHLUNG WITH LINEAR POLARIZATION CLOSE TO 100 PERCENT FROM THIN CRYSTAL TARGETS

Mozley and de Wire (1) have pointed out that bremsstrahlung from thin crystals can be monochromatized if one strongly collimates the photon beam. In recent papers (2) it was shown that the linear polarization of uncollimated coherent bremsstrahlung can be raised if the crystal is orientated in such a manner that one gets the main contribution to the spectrum from one single reciprocal lattice point only. Here it will be shown that by combining this method of orientation of the crystal with strong collimation one gets not only one dominating monoenergetic spike in the spectrum due to this single reciprocal lattice point, but that, in addition, the polarization of the spike is increased to a very high value. A simple procedure is given for deriving these spectra and their polarization from some «universal» curves for silicon and diamond crystals. An estimate is given of the photon intensity which can be reached by this method. © 1968 Società Italiana di Fisica.