Characterizing a polarization splitting quartz crystal

Summary form only given. When energetic electrons inside a plasma have a preferred direction the x-rays emitted by the plasma can be polarized. Information about the electrons and the anisotropy of their velocity distribution can then be revealed by the x-ray spectrum´s polarization. Polarization typically measured with two crystals at a 45 degrees Bragg, can now be determined in a new way using one crystal. This crystal utilizes two sets of planes that diffract the incident x-rays in two directions that are perpendicular to each other and to the incident beam1. These diffracted x-rays are then linearly polarized perpendicularly to each other. The polarization splitting properties of quartz crystals were confirmed with the linearly polarized x-rays from the Advanced Photon Source. A crystal with surface cut [10-10] that splits polarization with [11-20] planes at 7.15 keV was among those tested. Bragg reflections at 45 degrees from the crystal´s [10-10] surface planes was then tested with x-rays from conical wire array z-pinches. These tests were aimed to verify the reflectivity of the planes intended for single crystal spectropolarimetric measurements in upcoming experiments.