Cross-delay line microchannel plate detector for Aspera SmallSat mission: characterization and testing

Aspera is a NASA Pioneers Mission designed to reach ultra-low surface brightness limits in the Far Ultraviolet (FUV). The SmallSat payload consists of two identical spectrograph channels, both sharing a single detector and operating between 1030 -1040 Angstrom. The FUV sensitivity of this mission hinges on the availability of high QE, low background, photon-counting detectors. Aspera uses a microchannel plate detector (MCP) designed and manufactured by Sensor Sciences. The detector is a small format, flat MCP stack with a CsI photocathode. A custom cross-delay line anode has been designed to optimize the resolution in two separate active areas on the detector, one from each spectrograph channel. We present characterization and testing performed at the University of Arizona with the Aspera flight electronics following the delivery of the flight model detectors.