Magnetic Compton scattering using the elliptical multipole wiggler at sector 11-ID-B

Magnetic Compton scattering has been used to measure the momentum distribution of magnetic electrons in several materials. The polarization and frequency tunability of the elliptical multipole wiggler (EMW) makes it an ideal source for magnetic Compton scattering experiments. We performed the measurements using 50, 100 and 150 keV photons simultaneously. The EMW was operated at Ky=14 (Ec=32 keV) and Kx between 0.6 and 1.03. The degree of circular polarization was about 80% or higher. The sample was mounted between the poles of an electromagnet in a field of 0.8 T. The majority of Compton scattering measurements were performed by switching the magnet polarity. Tests using an iron foil target gave a similar magnetic Compton profile by either switching the magnetic field or the photon helicity. A 9-element Ge solid state detector array was used for detection