Thin substrate grating array for sounding rocket and satellite payloads

This paper presents critical engineering aspects of a grating array for a sub-orbital rocket payload to make spectral observations in the soft X-ray regime. The off-plane grating mount is a natural solution to maximize throughput and resolution in the 1/4 keV to 1 keV range while minimizing envelope and mass. Replicated radial groove gratings are matched to the convergence angle of the telescope beam to limit aberrations. These lightweight gratings are mounted and aligned in an array which is not only efficient for rocket payloads, but can also be made suitable for the X-ray Grating Spectrometer on Constellation X.