Detector blockbased on arrays of 144 SiPMs and monolithic scintillators: A performane study

[EN] We have developed a detector block composed by a monolithic LYSO scintillator coupled to a custom made 12 12 SiPMs array. The design is mainly focused to applications such as Positron Emission Tomography. The readout electronics is based on 3 identical and scalable Application Specific Integrated Circuits (ASIC). We have determined the main performance of the detector block namely spatial, energy, and time resolution but also the system capability to determine the photon depth of interaction, for different crystal surface treatments. Intrinsic detector spatial resolution values as good as 1.7 mm FWHM and energies of 15% for black painted crystals were measured. & 2014 Elsevier B.V. All…

Timing results using an FPGA-based TDC with large arrays of 144 SiPMs

Silicon photomultipliers (SiPMs) have become an alternative to traditional tubes due to several features. However, their implementation to form large arrays is still a challenge especially due to their relatively high intrinsic noise, depending on the chosen readout. In this contribution, two modules composed of SiPMs with an area of roughly mm mm are used in coincidence. Coincidence resolving time (CRT) results with a field-programmable gate array, in combination with a time to digital converter, are shown as a function of both the sensor bias voltage and the digitizer threshold. The dependence of the CRT on the sensor matrix temperature, the amount of SiPM active area and the crystal type…

Next generation of the Albira small animal PET based on high density SiPM arrays

A new design of the small animal PET Albira system which detectors are based on arrays of SiPMs and monolithic LYSO scintillator is presented here. The system is made out of 3 rings of 8 detectors each, resulting on an axial and transaxial FOVs of 148 and 80 mm, respectively. The scanner is thermally stabilized using air-cooling. Working temperatures around 22–25°C are reached with individual detector variations around 0.2°C minimizing dark count rates and gain drifts. One of the most significant improvements of the current system is the accurate photon impact determination within the crystal volume, specially its depth of interaction. This allows the calculation of the true line of respons…

Position sensitive photosensors based on SiPM arrays

High-resolution multichannel Time-to-Digital Converter core implemented in FPGA for ToF measurements in SiPM-PET

In this contribution, Coincidence Resolving Time (CRT) results with the developed multichannel FPGA-TDC are showed as a function of different configurations for both, the sensor bias voltage and the digitizer threshold. The dependence of the CRT with the sensor matrix temperature, the amount of SiPM active area and the crystal type are also analyzed. Preliminary measurements carried out with a crystal array of 2 mm pixel size and 10 mm height have shown time resolutions for the entire 144 SiPM two-detectors ensemble as good as 800 ps.