Hard X-Ray Reflectivity Of Spherically Bent Mica Crystals

M. Sánchez del Río 1) , A. Ya. Faenov 2) , T.A. Pikuz 2) , A. Souvorov 1) and A.K. Freund 1)

1) European Synchrotron Radiation Facility, BP 220, 38043 Grenoble Cedex, France 
2) Multicharged Ions Spectra Data Center of VNIIFTRI, Mendeleevo, Moscow region 141570 Russia
Abstract. 

Mica crystals are used as soft x-ray and neutron monochromators, as well as for
imaging applications, in particular for plasma x-ray diagnostics. Although the d-spacing for mica
is large (2d=19.88 Å), it can be used for hard x-ray applications by exploiting the large number
of intense high diffraction orders. We have measured diffraction profiles of mica crystals at the
ESRF BM5 beamline to study the suitability of these crystals for hard x-ray applications. Two
good quality mica crystal curved following an spherical shape with curvature radii of 10 and 15
cm were analyzed. A micrometry incident beam was prepared to avoid smearing the rocking
curve with the angular spread induced by the beam projection on the crystal surface. Many
diffraction orders from with indices from (0,0,6) to (0,0,38) were recorded at photon energies of
12, 16 and 20 keV.