Harold S. Barnard

We describe an approach to harmonic suppression in soft X-ray monochromators by engineering the reflection grating’s diffraction pattern to approximate a sinusoidal amplitude. At synchrotron and free-electron laser sources, X-ray beamlines powered by insertion devices produce a spectrum containing harmonic photon energies that can couple unwanted light into experiments. Beamlines in the soft X-ray energy range (100 eV to 2 keV) commonly employ energy-filtering elements to suppress these harmonics.

Our experiments afforded two principal findings with regard to Gilsocarbon graphite’s mechanical properties. First, with macro-scale tests, the maximum flexural strength of the graphite was found to be about 30% higher at 1,000?°C than at ambient temperature, specifically rising from ?25?MPa at 20?°C to ?32?MPa at 1,000?°C (Fig. 1a).