Study of scintillating materials and readout techniques for the detection of high energy electromagnetic radiation.

This project will contain the following parts: 1. Optimization of a small animal Positron Emission Topograph scanner using BaF2-scintillators and photosensitive wire chambers . This instrument is a test bench for a new detection technique for gamma rays . The prototype instrument is now essentially finished, and the next years will be devoted to evaluating it in real biomedical applications . This will certainly imply improvements on the software and probably also of the hardware , in function of the experience gained with the instrument . 2. The very recent development of Avalanche Photo diodes (APD's) as new, purely solid state photo detectors with internal gain, leads one to expect that the expensive and bulky glass multiplier tubes will, in the future, be replaced by purely solid state light detectors . We intend to study the possibilities of using APD's to readout scillating light in the detection of X-rays and gamma rays . We will study different scillating materials and see the energy and time resolution which can be achieved for different APD scintillator combinations . I this study the applcations envisioned will be PET and high energy physics calorimetry in the framework of the CERN project LHC .