The current response and the pulse response of a microchannel plate, MCP, to X-rays incident at an angle of 45 deg in the energy range of 8 to 100 keV were measured. The X-ray detection efficiency, pulse height distributions, and sensitive depth of the MCP were determined from these data. Detection efficiency extrapolates to zero below 8 keV, and ranges between values of 1% and 2.6% above this energy, much higher than anticipated from previous measurements for oblique incidence below 6 keV. When compared to previous measurements at higher energies, it was concluded that MCP's have a relatively constant detection efficiency in the energy range 10 to 600 keV, which was a rather unique property as compared to other X-ray detectors. It was found that the shape of current response curves differs somewhat from the shape of efficiency curves, that pulse height distributions were proportional to pulse height to the -1.1 to -1.6 power, and that 90% of the current originated in the first 25 to 30% of the MCP thickness.
NASA STI/Recon Technical Report N
- Pub Date:
- March 1977
- Plates (Structural Members);
- X Rays;
- Instrumentation and Photography