We developed a fully digital implementation of the Silicon Photomultiplier. The sensor is based on a single photon avalanche photodiode (SPAD) integrated in a standard CMOS process. Photons are ...detected directly by sensing the voltage at the SPAD anode using a dedicated cell electronics block next to each diode. This block also contains active quenching and recharge circuits as well as a one bit memory for the selective inhibit of detector cells. A balanced trigger network is used to propagate the trigger signal from all cells to the integrated time-to-digital converter (TDC). Photons are detected and counted as digital signals, thus making the sensor less susceptible to temperature variations and electronic noise. The integration with CMOS logic has the added benefit of low power consumption and possible integration of data post-processing. In this paper, we discuss the sensor architecture and present first measurements of the technology demonstrator test chip.
Beam test of FARICH prototype with digital photon counter Barnyakov, A.Yu; Barnyakov, M.Yu; Bobrovnikov, V.S. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2013, Letnik:
732
Journal Article
Recenzirano
In June 2012 we tested a Focusing Aerogel RICH detector prototype based on Digital Photon Counters (DPC) by Philips at the CERN PS T10 beam line with a particle momentum up to 6GeV/c. The prototype ...comprises a 20×20cm2 photon detector with 48×48 DPC pixels. In order to reduce the dark count rate, the photon detector was cooled to −40°C in addition to disabling individual DPC's microcells. A four layer focusing aerogel radiator with 200mm focal distance was studied. We obtained a Cherenkov angle resolution of 3.61±0.04mrad. The mean number of photoelectrons in a ring is 12. Directly measured π/K separation at 6GeV/c momentum is 3.5σ, μ/π separation is 5.3σ at 1GeV/c. A comparison with a Monte Carlo simulation is presented as well.
•Focusing Aerogel RICH prototype with Digital Photon Counters by Philips was built.•The prototype was tested at the CERN PS T10 beam line.•We observed Cherenkov rings with 12 photoelectrons in average.•Timing resolution of DPCs is 48ps for single photons.•Cherenkov angle resolution is 3.64±0.04mrad per ring.
Tests of FARICH prototype with precise photon position detection Barnyakov, A.Yu; Barnyakov, M.Yu; Basok, I.Yu ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2014, Letnik:
766
Journal Article
Recenzirano
In June 2012 a FARICH prototype from Philips Digital Photon Counting (PDPC) based on a photon camera with dimensions of 200200 mm has been tested at CERN. Remarkable particle separation has been ...achieved with a 4-layer aerogel sample: the pi /K separation at a 6 GeV/c momentum is 3.5 sigma , the mu / pi mu / pi separation is 5.3 sigma at 1 GeV/c. The analysis of the data has shown that the main contribution to the accuracy of the ring radius measurement comes from aerogel. The development of focusing aerogels is proceeding in two main directions: tuning of production technology of multilayer blocks and development of a new production method with continuous density (refractive index) gradient along the block depth. The beam test was carried out in December 2012-January 2013 at the electron beam test facility at the VEPP-4 M e super(+)e super(-) collider. The goal of this test was to measure different single layer and focusing aerogel samples, both multilayer and gradient. Aerogel samples were tested with a PDPC FARICH prototype. A part of DPC SPADs in each pixel was disabled to form an active area of 11 mm super(2). The collected data proved that gradient aerogel samples focus Cherenkov light.
Arrays of digital Silicon Photomultipliers (dSiPMs) have been developed. The arrays consist of 4 × 4 chips, each containing 2 × 2 dSiPMs, resulting in 8 × 8 dSiPMs on one array. With a pitch of 4 mm ...× 4 mm of the dSiPMs, the outer dimension of the array is 32 mm × 32 mm. To show the performance of the detector array, we investigated its intrinsic performance with respect to timing resolution using an external electronic trigger and picosecond laser pulses acting as an optical trigger. In addition, we show results of coupling arrays of 8 × 8 LYSO crystals with 4 mm × 4 mm pitch and 22 mm length to the detector arrays leading to a 1:1 coupling between the individual scintillator crystals and the dSiPM pixels. Two arrays have been operated in coincidence using 22 Na as a source for annihilation gamma radiation in order to record energy and coincidence timing resolution.
We have investigated the impact of intercrystal crosstalk on the spatial resolution of whole body PET detectors with different depth-of-interaction (DOI) readout schemes by validated Monte Carlo ...simulations. Readout schemes providing both discrete and continuous DOI information were analyzed. Detectors using scintillator crystals of different sizes and different stopping power (LYSO, LaBr 3 ) were modeled. The results show a similar improvement for the spatial resolution at full width at half maximum across the field of view for all investigated methods. Concerning the resolution at full width at tenth maximum, the discrete approach using two offset layers of crystals is most affected by intercrystal scatter. Continuous DOI readout is least impaired by intercrystal scatter and shows the best results for the full width at tenth maximum.
In this paper we present the first fully digital implementation of the Silicon Photomultiplier. The chip design is based on the technology demonstrator chip presented in. The new sensor represents a ...self-contained detector including a JTAG controller for configuration and test, single-ended and differential clock and test input signals, an integrated acquisition controller and two serial data outputs. The sensor is based on a single photon avalanche photodiode (SPAD) technology integrated in a standard CMOS process flow. Photons are detected directly by sensing the voltage at the SPAD terminal using a dedicated cell electronics block next to each diode. This block also contains active quenching and recharge circuits as well as a one bit memory for the selective activation of individual detector cells. A balanced trigger network is used to propagate the trigger signal from all cells to the two integrated time-to-digital converters. Photons are detected and counted as digital signals, thus making the sensor less susceptible to temperature variations and electronic noise. The resulting data packets are transferred to the readout system through a serial data interface. In this paper, we discuss the new sensor architecture and evaluate its performance.
The Philips Digital Photon Counter (DPC) is a silicon photomultiplier combining Geiger-mode avalanche photodiodes (G-APD) and dedicated readout electronics in the same chip. The DPC is a promising ...photon sensor for future RICH detectors. A known issue of G-APD is its sensitivity to radiation damage. Two DPC sensors were tested using 800MeV/c protons. An increase of dark counting rate with proton fluence up to 4·1011cm−2 has been measured.
•Radiation hardness of the Philips Digital Photon Counter was tested using protons.•Proton fluence of up to 4·1011cm−2 was accumulated.•Dark counting rate increased by about 4 orders of magnitude at maximum fluence.
We developed a fully digital Silicon Photomultiplier (dSiPM) of 3.8 mm × 3.3 mm in size containing 8188 individual Geiger-mode cells. Each detected photon is directly converted into a digital signal ...in each of the Geiger-mode cells of the sensor. In addition, the complete trigger logic and a time-to-digital converter are integrated into the sensor. To show the performance of the sensor, LYSO crystals of different sizes were coupled to the sensor. The coincidence timing resolution for 3 mm × 3 mm × 5 mm LYSO crystals using a 22 Na source amounts to 153 ps FWHM. The energy resolution at 511 keV was determined to be 10.7 % for 4 mm × 4 mm × 22 mm crystals. It is shown that saturation correction can be done without prior need for sensor calibration. The temperature dependence of the photon detection efficiency was found to be -0.6 %/°C including the temperature variation of the light output of LYSO.
The quality of PET images depends on the position, energy and time resolution of the gamma detector, which usually consists of scintillation crystals coupled to an array of photomultiplier tubes ...(PMTs). We have developed a simulation tool which models the conversion of scintillation photons into PMT waveforms, thereby bridging the gap between Monte Carlo simulations of the gamma interaction and pure electronics simulations of the data acquisition system. In our model, we track the scintillation photons individually from the crystal through the light guide to the photocathode of the PMT. The PMT characteristics are treated on a single photoelectron basis, incorporating pulse height distribution and single-photon response as well as spatially dependent quantum efficiency, transit time and transit time spread. From the PMT waveforms, we derive the position, energy and time resolution. The time resolution depends on the scintillator material, the PMT properties and the time-stamping method. By separating the different contributions, the limiting factors in the performance of a detector can be identified, facilitating its optimization. A comparison with measured data is included.
