Variable Line Spacing diffraction grating for ID32 beamline

Manufacturing of a Variable Line Spacing reflective X-ray diffraction grating for use on the ESRF Beamline ID32 in the energy range 300-1800 eV. The ESRF will supply polished, spherical (R=26m) grating blanks made of silicon upon which the chosen supplier will manufacture the grating structures with continuously varying line density. The required central line density is 1200 l/mm. To maximize the diffraction efficiency the grating structures shall be blazed. Supply will include gold or platinum coating of the gratings. The ESRF will integrate the gratings into a high-efficiency RIXS spectrometer.