Investigation of Electronic Signal Processing Chains for a Prototype TOF-PET System With 100-ps Coincidence Time...

Area of Science:

• Medical Physics
• Instrumentation
• Nuclear Science

Background:

• Accurate timing is crucial for Time-of-Flight Positron Emission Tomography (TOF-PET) imaging.
• Developing advanced detector electronics is key to enhancing TOF-PET resolution.
• Silicon Photomultipliers (SiPMs) are increasingly used in PET detectors due to their compact size and high sensitivity.

Purpose of the Study:

• To evaluate the coincidence time resolution (CTR) performance of four mixed-signal front-end electronic readout configurations for TOF-PET detectors.
• To identify the optimal readout configuration for achieving sub-100 picosecond (ps) CTR.
• To assess the impact of different electronic components on timing precision.

Main Methods:

• Utilized "fast LGSO" crystal segments coupled to linear arrays of Silicon Photomultipliers (SiPMs).
• Experimentally acquired coincidence data using four distinct front-end readout configurations: RF amplifiers, ASIC-based discriminator, and combinations thereof.
• Employed a low-jitter Field Programmable Gate Array (FPGA)-based Time to Digital Converter (TDC) for timing measurements.

Main Results:

• The configuration combining a radio frequency (RF) amplifier, balun transformer, and discriminator ASIC achieved the best CTR.
• A timing resolution of 99.4 ± 1.9 ps Full Width at Half Maximum (FWHM) was recorded.
• This result demonstrated a significant improvement of over 20 ps compared to configurations using only RF amplifiers or ASIC-based discriminators.

Conclusions:

• The optimized mixed-signal front-end readout configuration significantly enhances CTR in TOF-PET detectors.
• The combination of RF amplifier, balun transformer, and discriminator ASIC is a promising approach for achieving high-precision timing in PET imaging.
• Further development in detector electronics can lead to improved diagnostic capabilities in TOF-PET.