Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8172660 | Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | 2015 | 5 Pages |
Abstract
The best Coincidence Time Resolution (CTR) obtained so far - with very short crystals of 3-5Â mm in length - reach values between 100 and 150Â ps. Such crystals are not really practical for a TOF PET imaging device, since the sensitivity is quite small for the detection of the 511Â keV gammas resulting from a positron annihilation. We present our setup and measurements using 15Â mm length crystals; a length we regard as reasonable for a TOF-PET scanner. We have used a new series of Silicon Photo-Multipliers (SiPM) manufactured by Hamamatsu. These are the High Fill Factor (HFF) and Low Cross-Talk (LCT) Multi-Pixel Photon Counters (MPPC). We have compared three different crystals, LFS-3 (supplied by Zecotek) and two samples of LYSO (manufactured by Saint Gobain and CPI). We have obtained an excellent value of 148 ps for the Coincidence Time Resolution (CTR) with two LFS-3 crystals (15Â mm long) mounted on each side of a 22Na radioactive source with the HFF-MPPCs at 3.3Â V over-voltage. Our results are148Â ps obtained with LFS-3 and 170Â ps with LYSO crystals using identical SiPMs and electronics.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Instrumentation
Authors
K. Doroud, M.C.S. Williams, A. Zichichi, R. Zuyeuski,