The PCA is an array of five proportional counters with a total collecting area of 6500 square cm. The instrumental properties are:
- Energy range: 2 - 60 keV
- Energy resolution: < 18% at 6 keV
- Time resolution: 1 microsec
- Spatial resolution: collimator with 1 degree FWHM
- Detectors: 5 proportional counters
- Collecting area: 6500 square cm
- Layers: 1 Propane veto; 3 Xenon, each split into two; 1 Xenon veto layer
- Sensitivity: 0.1 mCrab
- Background: 90 mCrab
Events detected by the PCA will be processed on board by the Experiment Data System (EDS) before insertion into the telemetry stream.
The PCA is being built by the Laboratory for High Energy Astrophysics at Goddard Space Flight Center. The principal investigator is Dr. Jean H. Swank.