Bragg reflectivity of X-rays: At the limit of the possible
Researchers utilizing high-brightness x-rays at the U.S. Department of Energy Office of Science’s Advanced Photon Source at Argonne National Laboratory have demonstrated that synthetic, nearly defect-free diamond crystals can reflect more than 99% of hard x-ray photons backward in Bragg diffraction, with a remarkably small variation in the magnitude of reflectivity across the sample.
Theoretical analysis presented in the Nature Photonics paper establishes that diamond has the highest (higher than any other crystal) Bragg reflectivity due to the uniquely small ratio of the extinction length in Bragg diffraction to the absorption length. Even in backscattering, where the reflectivity is lowest, it was thought to be more than 99%, and this has now been demonstrated.
Systematic observations of the more than 99% reflectivity show that high-reflectivity mirror limitations in the regime of hard x-rays have been eliminated.
Is something similar possible for shielding against gamma rays (which may or may not be emitted by a p-11B fusion process)?