123 research outputs found
A compact, high-density gamma-detection module for Time-of-Flight measurements in PET applications
No full textWe present a very compact γ-detection module primarily designed for PET applications. On a total area of about 30×30mm2, 144 SiPM photodetectors coupled to scintillator crystals are read out individually with fast timing ASICs. The core of the module is a LTCC ceramic substrate with internal water channels for efficient and stable liquid cooling. The top side of the LTCC is covered by 12×12 SiPMs in a regular pitch of 2.5 mm. The SiPMs are designed in the RGB-HD technology from FBK with a single cell size of 25×25μm2, very low dark-count rate and stable performance over a wide temperature range from 0 to 20 °C. The readout of the SiPMs is done with 4 specialized PETA5 ASICs flip-chip mounted to the bottom side of the substrate. Each chip has 36 readout channels (available in single or differential ended configuration) with self-triggered hit detection, a very low noise discriminator, signal amplitude integration and digitization, a TDC with 50 ps binwidth, neighbor logic and fast veto mechanisms. The full height of the assembly, including the connector to the main readout board, is less than 1 cm. In a 1:1 coupling configuration with 10 mm high LYSO scintillator arrays for detection of 511 keV gammas, the module has already reached 205 ps CRT time resolution (FWHM in coincidence between channels on two different modules), sufficient for ToF operation in PET. The module design, details on chip operation and latest results with LYSO arrays are described
Performance of FBK SiPMs coupled to PETA3 read-out ASIC for PET application
No full textIn this paper we show the energy and timing resolution performances of FBK SiPMs coupled to the PETA3 ASIC for PET application. We developed a measurement set-up to characterize single SiPMs coupled to scintillator exploiting the detector stack developed within the HYPERImage project. In this way we are able to characterize the combined SiPM/ASIC performance with the same signal chain (from the sensor to the ASIC board) used in the PET system. We show that using two scintillator detectors, composed of a 3x3x5mm^3 LYSO crystal coupled to a 3x3mm^2 SiPM, an intra-stack CRT of about 200ps FWHM can be obtained
A Compact, Water Cooled, 144-Channel Photo Sensor Module For γ Detection In PET
No full textWe present a very compact photo sensor module with an area of 32.8x32.0mm^2 containing 12x12 Silicon Photomultipliers (SiPMs) in a pitch of (2.5mm)^2. The readout of the 144 channels is done by highly specialized PETA5 ASICs (Position Energy Timing Asic) which offer self triggered hit detection (including neighbor logic and fast veto mechanisms), time stamping with 50ps bin width and digital amplitude measurement. The module uses a substrate which is cooled by a fluid running in internal channels. The SiPMs are glued and
wire bonded in a regular pattern on the top side, the ASICs are
flip chip mounted at the bottom side. Several modules will be
plugged into a control and data readout PCB. The full height
of these parts is below 1cm. The module can be used to read
scintillator crystal arrays with a pitch of only 2.5mm in a 1:1
coupling, or smaller crystals with light spreaders. We present the
module design and the first results obtained with 1:1 coupled
LYSO crystal arrays
Potentiometric Rotating Ring Disk Electrode Study of Interfacial pH during CO2 Reduction and H-2 Generation in Neutral and Weakly Acidic Media
No full textB.M.T. acknowledges support from the National Institute of Standards and Technology-National Research Council Post-doctoral Fellowship
A sub-millimeter resolution detector module for small-animal PET applications
No full textWe present a gamma detection module optimized for very high resolution PET applications,
able to resolve arrays of scintillating crystals with sub-millimeter pitch. The detector is
composed of a single ceramic substrate (LTCC): it hosts four flip-chip mounted PETA5 ASICs on
the bottom side and an array of SiPM sensors on the top surface, fabricated in HD-RGB technology
by FBK. Each chip has 36 channels, for a maximum of 144 readout channels on a sensitive area
of about 32mm x 32 mm. The module is MR-compatible. The thermal decoupling of the readout
electronics from the photon sensors is obtained with an efficient internal liquid channel, integrated
within the ceramic substrate. Two modules have been designed, based on different SiPM topologies:
• Light spreader-based: an array of 12 x 12 SiPMs, with an overall pitch of 2.5 mm, is coupled
with a scintillators array using a 1mm thick glass plate. The light from one crystal is spread
over a group of SiPMs, which are read out in parallel using PETA5 internal neighbor logic.
• Interpolating SiPM-based: ISiPMs are intrinsic position-sensitive sensors. The photon diodes
in the array are connected to one of the four available outputs so that the center of gravity
of any bunch of detected photons can be reconstructed using a proper weight function of the
read out amplitudes. An array of ISiPMs, each 7.5mmx5mm sized, is directly coupled with
the scintillating crystals.
Both modules can clearly resolve LYSO arrays with a pitch of only 0.833 mm. The detector can
be adjusted for clinical PET, where it has already shown ToF resolution of about 230 ps CRT at
FWHM. The module designs, their features and results are described
Solid-State Detector Stack for ToF-PET/MR
No full textThe integration of PET and MR imaging requires a novel type of highly integrated PET detector. To cope with geometric constraints and MR compliance a very compact detector stack was built within the HYPERImage consortium. This allows a four side buttable detector module design with a low dead space in between. The scintillation light coming from a LYSO array is converted in a SiPM sensor tile with a high packing fraction and a high photo detection efficiency to provide sub-ns time-of-flight timing resolution. The analog signals coming from the SiPM elements are digitized close to the sensor to minimize potential crosstalk. A custom mixed-signal ASIC was integrated on a 64 channel sensor stack which is powered and controlled by an FPGA interface board. The complete sensor stack is assembled and characterized to extract the PET relevant parameters, in particular energy, timing and spatial resolution for clinical and pre-clinical PET/MR applications
A preclinical PET/MR insert for a human 3T MR scanner
No full textWe describe the design of a prototype preclinical PET/MR system capable of scanning small animals up to the size of a rabbit. The scanner uses highly sensitive and fast LSO/silicon-photomultiplier arrays as detector elements, direct digitization with a dedicated ASIC and integrated digital singles processing. Special measures are taken to improve the MR-compatibility of this design. Measurements of a prototype detector were performed inside 1.5 T and 3 T MRI-systems. Even under high gradient-slew-rates and RF-pulses disturbance energy- and coincidence timing-resolution of ~18% and 530 ps (FWHM) respectively have been measured. The presented work is part of the EU FP7 project HYPERImage, Grant Agreement N degrees 201651,
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