TY - CHAP A1 - Streun, M. A1 - Al-Kaddoum, R. A1 - Parl, C. A1 - Pietrzyk, U. A1 - Ziemons, Karl A1 - Waasen, S. van T1 - Simulation studies of optical photons in monolithic block scintillators T2 - 2011 IEEE Nuclear Science Symposium Conference Record (NSS/MIC) N2 - The interest in PET detectors with monolithic block scintillators is growing. In order to obtain high spatial resolutions dedicated positioning algorithms are required. But even an ideal algorithm can only deliver information which is provided by the detector. In this simulation study we investigated the light distribution on one surface of cuboid LSO scintillators of different size. Scintillators with a large aspect ratio (small footprint and large height) showed significant position information only for a minimum interaction depth of the gamma particle. The results allow a quantitative estimate for a useful aspect ratio. Y1 - 2012 SN - 978-1-4673-0120-6 (electronic ISBN) SN - 978-1-4673-0118-3 (print ISBN) U6 - http://dx.doi.org/10.1109/NSSMIC.2011.6154621 SP - 1380 EP - 1382 PB - IEEE CY - New York ER - TY - JOUR A1 - Ziemons, Karl A1 - Heinrichs, U. A1 - Streun, M. A1 - Pietrzyk, U. T1 - Validation of GEANT3 simulation studies with a dual-head PMT ClearPET™ prototype JF - 2003 IEEE Nuclear Science Symposium Conference Record, Vol. 5 N2 - The ClearPET™ project is proposed by working groups of the Crystal Clear Collaboration (CCC) to develop a 2nd generation high performance small animal positron emission tomograph (PET). High sensitivity and high spatial resolution is foreseen for the ClearPET™ camera by using a phoswich arrangement combining mixed lutetium yttrium aluminum perovskite (LuYAP:Ce) and lutetium oxyorthosilicate (LSO) scintillating crystals. Design optimizations for the first photomultiplier tube (PMT) based ClearPET camera are done with a Monte-Carlo simulation package implemented on GEANT3 (CERN, Geneva, Switzerland). A dual-head prototype has been built to test the frontend electronics and was used to validate the implementation of the GEANT3 simulation tool. Multiple simulations were performed following the experimental protocols to measure the intrinsic resolution and the sensitivity profile in axial and radial direction. Including a mean energy resolution of about 27.0% the simulated intrinsic resolution is about (1.41±0.11)mm compared to the measured of (1.48±0.06)mm. The simulated sensitivity profiles show a mean square deviation of 12.6% in axial direction and 3.6% in radial direction. Satisfactorily these results are representative for all designs and confirm the scanner geometry. Y1 - 2004 SN - 1082-3654 SP - 3053 EP - 3056 ER -