Calibration of a silicon crystal for absolute nuclear spectroscopy

• Published in: Journal of applied crystallography Vol. 43; no. 2; pp. 293 - 296
• Main Authors: Massa, Enrico, Mana, Giovanni, Kuetgens, Ulrich, Ferroglio, Luca
• Format: Journal Article
• Language: English
• Published: 5 Abbey Square, Chester, Cheshire CH1 2HU, England International Union of Crystallography 01.04.2010; Blackwell Publishing Ltd
• Subjects: atomic-scale displacement metrology; Calibration; Silicon; silicon lattice parameters; Spectrum analysis; X-ray interferometry; γ-ray diffractometry
• ISSN: 1600-5767; 0021-8898; 1600-5767
• DOI: 10.1107/S0021889810001652

To tie the wavelengths of γ‐rays to a visible standard is a key element of accurate determinations of the Planck constant and of tests of the Einstein mass–energy equivalence. This link is achieved via small diffraction angle measurements and perfect single crystals, the lattice parameter of which is determined by combined X‐ray and optical interferometry. The present paper concerns the lattice parameter measurement of an Si crystal, of a natural isotopic composition, designed to be used both as the analyser crystal of an X‐ray interferometer and the reference grating of a γ‐ray spectrometer.