Soft X-Ray Imaging Experiments With Charge Coupled Devices (CCDs) And Some Astronomical Applications

We have evaluated the suitability of a CCD for use as a soft X-ray (E < 2 keV) image detector for astronomical and laboratory applications. The sensitivity of a currently available CCD to soft X-ray radiation has been measured. It was found to be comparable to that of other presently available X-ray image detectors. Back-illuminated CCDs which will be available soon offer significantly greater sensitivity, especially at longer X-ray wavelengths. Theoretical X-ray spectra of hot optically thin plasma sources such as those found in the solar corona or supernova remnants have been convolved with the response characteristics of the various CCDs, and minimum detectable fluxes have been determined as a function of plasma temperature. When operated at very low temperatures with optimal noise adjustment, the CCD may be used as an array of single X-ray photon detectors of excellent spectral and reasonable spatial resolution.