Characterization of microchannel plates for plasma x-ray diagnostics in the 0.6–82-keV energy region

Current response characteristics of microchannel plates (MCPs) x-ray detectors have been measured in a wide energy range from 0.6 to 82 keV using synchrotron radiation. In the current response curve with continuous photon energy, some discontinuities have been observed to correspond to absorption edges of elements which are the constituents of MCP glass and electrode materials (Si, Pb, Ba, and Fe). The dependence of the MCP response on the incident angle of x rays to the channel axis, θ, is also investigated. The characteristics change from the cot θ dependence for soft x rays (hν<4 keV) to the sec θ one for hard x rays (hν>60 keV). These results could provide guidelines on the design of x-ray diagnostic instruments using MCPs.