Search

At the core of the AGILE scientific instrument, designed to operate on a satellite, there is the Gamma Ray Imaging Detector (GRID) consisting of a Silicon Tracker (ST), a Cesium Iodide Mini-Calorimeter and an Anti-Coincidence system of plastic scintillator bars. The ST needs an on-ground calibration with a g-ray beam to validate the simulation used to calculate the energy response function and the effective area versus the energy and the direction of the g rays. A tagged g-ray beam line was designed at the Beam Test Facility (BTF) of the INFN Laboratori Nazionali of Frascati (LNF), based on an electron beam generating g-rays through bremsstrahlung in a position-sensitive target. The g-ray energy is deduced by difference with the post-bremsstrahlung electron energy [1,2]. The electron energy is measured by a spectrometer consisting of a dipole magnet and an array of position sensitive silicon strip detectors, the Photon Tagging System (PTS). The use of the combined BTF-PTS system as tagged photon beam requires understanding the efficiency of g-ray tagging, the probability of fake tagging, the energy resolution and Contents lists available at SciVerse ScienceDirect

We report the performance of three prototype TeO2 macrobolometers, able to identify events due to energy deposited at the detector surface. This capability is obtained by thermally coupling thin active layers to the main absorber of the bolometer, and is proved by irradiating the detectors with alpha particles. This technique can be very useful in view of background study and reduction for the CUORE experiment, a next generation Double Beta Decay search based on TeO2 macrobolometers and to be installed in the Laboratori Nazionali del Gran Sasso.