Charge-coupled-device detection of soft x rays for grazing-incidence spectrometers

We describe calculations of the sensitivity of CCD’s to soft x rays incident at grazing angles. Soft-x-ray spectrometers based on a Rowland-circle geometry have a focal plane and hence detector surface at grazing incidence to the soft x rays. We model the penetration of the grazing-incidence soft x rays to the sensitive region of the CCD and predict the charge-collection efficiency as a function of wavelength. The results show significant advantages over microchannel plate intensified detection.