TY  - JOUR
A1  - Streun, M.
A1  - Chavan, U.
A1  - Lame, H.
A1  - Parl, C.
A1  - Müller-Veggian, Mattea
A1  - Ziemons, Karl
T1  - Treating the Gain Non-Uniformity of Multi Channel PMTs by Channel-Specific Trigger Levels
JF  - 2006 IEEE Nuclear Science Symposium Conference Record, Vol. 2.
Y1  - 2006
SN  - 1082-3654
SP  - 1301
EP  - 1304
CY  - San Diego, CA
ER  - 
TY  - JOUR
A1  - Streun, M.
A1  - Brandenburg, G.
A1  - Larue, H.
A1  - Parl, C.
A1  - Ziemons, Karl
T1  - The data acquisition system of ClearPET neuro - a small animal PET scanner
JF  - IEEE Transactions on Nuclear Science
N2  - The Crystal Clear Collaboration has developed a modular system for a small animal PET scanner (ClearPET). The modularity allows the assembly of scanners of different sizes and characteristics in order to satisfy the specific needs of the individual member institutions. The system performs depth of interaction detection by using a phoswich arrangement combining LSO and LuYAP scintillators which are coupled to Multichannel Photomultipliers (PMTs). For each PMT a free running 40 MHz ADC digitizes the signal and the complete scintillation pulse is sampled by an FPGA and sent with 20 MB/s to a PC for preprocessing. The pulse provides information about the gamma energy and the scintillator material which identifies the interaction layer. Furthermore, the exact pulse starting time is obtained from the sampled data. This is important as no hardware coincidence detection is implemented. All single events are recorded and coincidences are identified by software. The system in Jülich (ClearPET Neuro) is equipped with 10240 crystals on 80 PMTs. The paper will present an overview of the data acquisition system.
Y1  - 2006
SN  - 0018-9499
VL  - 53
IS  - 3
SP  - 700
EP  - 703
ER  - 
TY  - JOUR
A1  - Khodaverdi, M.
A1  - Weber, S.
A1  - Streun, M.
A1  - Parl, C.
A1  - Ziemons, Karl
T1  - High resolution imaging with ClearPET™ Neuro - first animal images
JF  - 2005 IEEE Nuclear Science Symposium Conference Record, Vol. 3
N2  - The ClearPET™ Neuro is the first full ring scanner within the Crystal Clear Collaboration (CCC). It consists of 80 detector modules allocated to 20 cassettes. LSO and LuYAP:Ce crystals in phoswich configuration in combination with position sensitive photomultiplier tubes are used to achieve high sensitivity and realize the acquisition of the depth of interaction (DOI) information. The complete system has been tested concerning the mechanical and electronical stability and interplay. Moreover, suitable corrections have been implemented into the reconstruction procedure to ensure high image quality. We present first results which show the successful operation of the ClearPET™ Neuro for artefact free and high resolution small animal imaging. Based on these results during the past few months the ClearPET™ Neuro System has been modified in order to optimize the performance.
Y1  - 2006
SN  - 1082-3654
SP  - 1641
EP  - 1644
ER  - 
TY  - JOUR
A1  - Streun, M.
A1  - Brandenburg, G.
A1  - Khodaverdi, M.
A1  - Larue, H.
A1  - Parl, C.
A1  - Ziemons, Karl
T1  - Timemark correction for the ClearPET™ scanners
JF  - 2005 IEEE Nuclear Science Symposium Conference Record, Vol. 4
N2  - The small animal PET scanners developed by the Crystal Clear Collaboration (ClearPETtrade) detect coincidences by analyzing timemarks which are attached to each event. The scanners are able to save complete single list mode data which allows analysis and modification of the timemarks after data acquisition. The timemarks are obtained from the digitally sampled detector pulses by calculating the baseline crossing of the rising edge of the pulse which is approximated as a straight line. But the limited sampling frequency causes a systematic error in the determination of the timemark. This error depends on the phase of the sampling clock at the time of the event. A statistical method that corrects these errors will be presented
Y1  - 2006
SN  - 1082-3654
SP  - 2057
EP  - 2060
ER  -