A silicon Compton imager

A Compton imager has been constructed using arrays of detectors with active areas of 11.4 times 11.4 cm
²
. These arrays are stacked 8 layers deep. 32-channel analog ASICs are used to read-out the arrays. This imager is a prototype for a large, high-efficiency Compton imager that will meet operational requirements of the Defense Threat Reduction Agency. The instrument created positron emission tomography (PET) images of multiple
²²
Na sources within its field of view. The image of a 1 mm point source had a measured full width half maximum (FWHM) of 1.25 mm or an intrinsic resolution of 0.75 mm. Using a known source position and partial energy deposition in the Compton imager, the initial gamma-ray energy was reconstructed. The energy resolution was 43 keV FWHM at 662 keV and 83 keV FHWM at 1173 keV. The resolution is dominated by the readout electronics resolution and will be improved