Photon detection with high gain avalanche photodiode arrays

The detection of light emitted in fast scintillating fiber bundles and Cerenkov radiators used for fiber calorimetry and tracking applications requires fast detector arrays with high sensitivity to short-wavelength photons. Photomultiplier tube arrays, the traditional imaging detectors for short-wavelength optical radiation, have limited spatial resolution and require expensive anti-magnetic shielding. We report on short-wavelength sensitivity improvement and detection efficiency performance for a new p-n junction planar structure silicon avalanche photodiode (APD) array, operated in Geiger mode. The APD array provides a high-sensitivity detector for applications which require mapping of light spatial distributions with single photon sensitivity.