Author/Authors :
Bellazzini، نويسنده , , R. and Spandre، نويسنده , , G. and Brez، نويسنده , , A. and Minuti، نويسنده , , M. and Baldini، نويسنده , , L. and Latronico، نويسنده , , L. and Massai، نويسنده , , M.M. and Omodei، نويسنده , , N. and Pesce-Rollins، نويسنده , , M. and Sgrٍ، نويسنده , , C. and Razzano، نويسنده , , M. and Pinchera، نويسنده , , M. and Bregeon، نويسنده , , J. and Kuss، نويسنده , , M. and Braem، نويسنده , , A.، نويسنده ,
Abstract :
We describe a UV photodetector with single photon (electron) counting and imaging capability. It is based on a CsI photocathode, a GEM charge multiplier and a self-triggering CMOS analog pixel chip with 105 k pixels at 50 μm pitch. The single photoelectron produced by the absorption of a UV photon is drifted to and multiplied inside a single GEM hole. The coordinates of the GEM avalanche are reconstructed with high accuracy (4 μm rms) by the pixel chip. As a result the map of the GEM holes, arranged on a triangular pattern at 50 μm pitch, is finely imaged.
