| Autor: |
Emilie Gaudin, Roger Lecomte, Louis Arpin, Jonathan Bouchard, Arnaud Samson, Christian Thibaudeau, Rejean Fontaine, Caroline Paulin |
| Rok vydání: |
2016 |
| Předmět: |
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| Zdroj: |
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD). |
| Popis: |
With the aim of improving the CNR of the LabPET II scanner, a method to correct the channel-to-channel coincidence time difference has been developed. The LabPET II, an avalanche photodiode-based PET scanner, features up to 55 000 channels which benefit from precise timing alignment. The correction process is fully automated and embedded in the scanner hardware and firmware. It uses a timing probe designed to react with the excess kinetic energy of a positron, enabling an absolute time reference of the positrons emission inside the probe. The time measurement is performed by a 312.5 ps time-to-digital converter (TDC) implemented in the LabPET II coincidence unit FPGA featuring a differential nonlinearity of −0.23 LSB peak and an integral nonlinearity of 0.14 LSB peak. The system computes probe-to-channel coincidences in order to obtain the absolute time difference between each channel of the scanner. The time correction is then applied to each channel to align all coincidence spectra, enhancing time resolution, thus improving CNR. Finally, these corrections are applied in real-time to each event during a typical PET acquisition. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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