Performance of a Compton telescope using position-sensitive germanium detectors

Abstract

We describe the use of position sensitive planar germanium detectors in a Compton telescope/camera. This Compton telescope achieves the very good energy resolution (/spl Delta/Etotal<4 keV) associated with germanium detectors and good position resolution (2 mm). By combining a 25/spl times/25 strip (2 mm pitch) detector with a 5/spl times/5 strip detector (9 mm pitch), we created a telescope with 625/spl times/25 pixel combinations. Using this detector pair, we have reconstructed positions with an angular resolution of 1 degree FWHM and 15 arcminute centroiding. Point sources are identified with less than 100 full energy events with simple image reconstruction. The angular resolution is currently limited by the uncertainty in the absolute position of the detectors and the size of the second detector pixels. We show the expected angular resolution when the pixel size no longer dominates the angular resolution and discuss proposed applications.