Author/Authors :
Limousin، نويسنده , , O and Arques، نويسنده , , M and Crétolle، نويسنده , , J and Lebrun، نويسنده , , F and Leray، نويسنده , , J.P and Baffert، نويسنده , , N and Lattard، نويسنده , , D and Martin، نويسنده , , J.L and Masson، نويسنده , , G and Noca، نويسنده , , A and Mathy، نويسنده , , F and Rostaing، نويسنده , , J.P and Trystram، نويسنده , , P and Villard، نويسنده , , P and Baron، نويسنده , , P and Delagnes، نويسنده , , E and Rouger، نويسنده , , M، نويسنده ,
Abstract :
A basic component called Polycell has been developed for the ISGRI CdTe γ-ray camera of the IBIS telescope on board the INTEGRAL satellite. This imager is an assembly of 16384 CdTe detectors (4×4 mm large, 2 mm thick) operating at room temperature. ISGRI covers the lower part (20 keV–1 MeV) of the IBIS energy range (20 keV–10 MeV). Detectors are arranged 4×4 on Polycells, where they are connected to their front-end electronics. The front-end electronics is based on radiation tolerant 4-channel analog–digital ASICs. The ASICs contain a low-noise charge-sensitive preamplifier (160e− rms; 1 pF load) and a pulse rise-time measurement in addition to the standard pulse-height measurement. This permits to compute a charge loss correction based on the charge drift time. The digital part includes the internal acquisition timing sequence as well as the dialogue with external electronics. After a description of the front-end electronics, we will present the improvements made on the new and final version of this hybrid mini CdTe γ-ray cameras. In conclusion, we will present the spectometric performance obtained owing to this modular device. A spectral resolution around 7% at 122 keV is obtained with this last generation of ASICs.
Keywords :
Front end I.C. chip , CdTe ?-ray camera , Space INTEGRAL satellite , Characterization multi-detector
