P. Buzhan - Academia.edu (original) (raw)
Papers by P. Buzhan
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2018
Portable dosimeter for ambient dose equivalent (H*(10)) and ambient dose rate equivalent (Ḣ*(10))... more Portable dosimeter for ambient dose equivalent (H*(10)) and ambient dose rate equivalent (Ḣ*(10)) measurements based on Silicon Photomultiplier (SiPM) coupled to CsI(Tl) scintillator was designed and tested. Nonequivalence of the scintillator to the human tissue is corrected by the method which uses restoration of the radioactive source energy spectrum from secondary electron spectrum in scintillator. Due to that, the energy dependence response of the dosimeter is lower then 20% in range 50-3000 keV. As measured by 137 Cs nuclide sources, a dynamic range 0.1 μSv/h-10 mSv/h with a sensitivity 30 cps/(μSv/h) are achieved. Temperature stability is better then 10% in range −40-+50 • C due to combination of Zener diode and adjustment of the bias supply with DAC based on thermometer data.
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
A coincidence timing resolution (CTR) of scintillation detectors based on SiPMs depends on both p... more A coincidence timing resolution (CTR) of scintillation detectors based on SiPMs depends on both photodetector and scintillator properties. The photodetector-related contribution is very important and has a considerable impact on the CTR. The CTR dependence on photon detection efficiency (PDE) is well studied and clarified, but as soon as advances in developments of fast scintillators and fast SiPMs make CTR approaching to a fundamental limit, a role of a single photon timing resolution (SPTR) is increased, and it requires more attention and studies. This study presents results of CTR measurements of LYSO crystals with “old” standard and timing optimized KETEK SiPM samples of 3×3 mm2 size obtained with developed digital signal processing. To complement and extend the studies on LYSO CTR with analysis on how SPTR affects multi-photon timing resolution (MPTR) with different light intensity profiles, experiments with different light sources were carried out and results were compared wit...
Journal of Physics: Conference Series, 2017
Digital signal processing (DSP) is an emerging trend in experimental studies and applications of ... more Digital signal processing (DSP) is an emerging trend in experimental studies and applications of various detectors including SiPMs. In particular, the DSP is recognized as a promising approach to improve coincidence timing resolution (CTR) of fast SiPM-based scintillation detectors. Single photon timing resolution (SPTR) is one of the key parameters affecting CTR, especially important in a case when CTR is approaching to its ultimate limits as, for example, highly demanded in Time-of-Flight PET. To study SiPM timing resolution, we developed a special DSP software and applied it to both SPTR and CTR measurements. These measurements were carried out using 3x3 mm2 KETEK SiPM samples of timing optimized and standard designs with 405 nm picosecond laser for SPTR and with 3x3x5 mm3 LYSO crystals and 511 keV Na-22 source for CRT. Results of the study are useful for further improvements of DSP algorithms and SiPM designs for fast timing.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2012
Instruments and Experimental Techniques, 2013
Dynamics of voltage recovery processes on silicon photomultipliers is experimentally and theoreti... more Dynamics of voltage recovery processes on silicon photomultipliers is experimentally and theoretically investigated. Special features of the voltage recovery in crystals with a great number of pixels are studied. Considerations on the configuration and selection of filter-element values in the supply circuit are stated. The expression for calculating the recovery time with an arbitrary number of operated pixels, taking the total number of pixels of the silicon photomultiplier, resistance value of horizontal current spreading over p- and n-regions of the pixels, and outer-element values into account, is obtained. The analytic expressions and SPICE simulation data are compared with the experimentally measured voltages across the load.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2009
One of the major drawbacks of a SiPM is due to the so-called cross-talk effect. Often, one single... more One of the major drawbacks of a SiPM is due to the so-called cross-talk effect. Often, one single photon in a chain reaction can generate more photons and thus can fire more than one micro-cell of a SiPM. This can be considered as a noise in the signal multiplication process and this degrades the signal/noise ratio. In self-trigger schemes this noise can be so high that it can make operating them difficult at low threshold settings. For the past few years, we have dwelt on this effect aiming to suppress it at the design stage. One can use (a) trenches around the micro-cells for suppressing the direct photon ''communication'' channel and (b) the so-called double p-n junction for suppressing photon-induced charge ''communication'' in neighbor pixels. The low cross-talk is mandatory, for example, for producing SiPM-based light sensor modules for the Imaging Atmospheric Cherenkov Technique projects for ground-based gamma-ray astrophysics. We produced and tested a few modules consisting of 4 SiPMs, each with a size of 5 mm  5 mm of custom production type. We report here on the main parameters of these units.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2006
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2006
The state of art of the Silicon Photomultipliers (SiPM's)-their features, possibilities and appli... more The state of art of the Silicon Photomultipliers (SiPM's)-their features, possibilities and applications-is given. The significant progress of this novel technique of photo detection is described and discussed.
Journal of Physics: Conference Series
The technology of charged particles detection by a plastic scintillator light from which is colle... more The technology of charged particles detection by a plastic scintillator light from which is collected by wavelength shifting fiber (WLS) on Silicon Photomultiplier (SiPM) is widely used in high energy physics. We present in this article the new personnel surface contamination monitoring assembly based on that technology as a result of about two years R&D research. This assembly is used for contamination control of hands, feet and clothes at nuclear power plants, nuclear facilities and other objects that work with radioactive materials. Setup design, main parameters and its measurement procedures are presented. It has high efficiency to α and β particles in wide energy range, large dynamic range, very good area uniformity and excellent temperature stability. Dynamic range of measured particle fluence rate equals: 1 – 106 Hz·cm2·min for β-module and 0.1 – 2·104 Hz·cm2·min for α-module. Variations of the module response in temperature range from –20 C up to +50 C doesn`t exceed 3%.
A coincidence timing resolution (CTR) of scintillation detectors based on SiPMs depends on both p... more A coincidence timing resolution (CTR) of scintillation detectors based on SiPMs depends on both photodetector and scintillator properties. The photodetector-related contribution is very important and has a considerable impact on the CTR. The CTR dependence on photon detection efficiency (PDE) is well studied and clarified, but as soon as advances in developments of fast scintillators and fast SiPMs make CTR approaching to a fundamental limit, a role of a single photon timing resolution (SPTR) is increased, and it requires more attention and studies. This study presents results of CTR measurements of LYSO crystals with “old” standard and timing optimized KETEK SiPM samples of 3×3 mm2 size obtained with developed digital signal processing. To complement and extend the studies on LYSO CTR with analysis on how SPTR affects multi-photon timing resolution (MPTR) with different light intensity profiles, experiments with different light sources were carried out and results were compared with an analytical model of SiPM timing resolution.
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment - NUCL INSTRUM METH PHYS RES A, 2003
The Silicon Photomultiplier (SiPM) is a semiconductor device consisting of many photon microcount... more The Silicon Photomultiplier (SiPM) is a semiconductor device consisting of many photon microcounters (103mm−2) positioned on a common Si substrate. SiPM operates in a limited Geiger mode and has single photoelectron gain (106) and photon detection efficiency (20%) similar to vacuum PMT. Main SiPM features are described and a number of examples of its possible applications are demonstrated, such as scintillator fiber readout, scintillator tiles+WLS readout, imaging Cherenkov counter timing. These SiPM applications are based on experimental test data and SiPM performance is compared with other photodetectors (PMT, APD, HPD, VLPC).
At present the development of a silicon photomultiplier (SiPM), being a microcell photodiode with... more At present the development of a silicon photomultiplier (SiPM), being a microcell photodiode with Geiger amplification, is going on [1]. Such devices are capable of registering faint light bursts, what, in aggregate with their small dimensions, makes them highly promising for application as photoreceivers in scintillation fiber detectors. Relying on the studies of the latter and those of SiPM, a bread-board model of a tracking detector of relativistic particles, containing 16 channels, has been designed and created. The characteristics of SiPM have been studied with a beta-source. A read-out electronic unit, containing preamps, shapers, discriminators, has been designed to collect the signals of SiPM. The characteristics of this unit are presented and the prospects of its application in experimental physics are discussed.
2000 IEEE Nuclear Science Symposium. Conference Record (Cat. No.00CH37149), 2000
The new design, principle of operation, and physical processes in a microcell Si avalanche photod... more The new design, principle of operation, and physical processes in a microcell Si avalanche photodiode with limited Geiger mode gain muCAPD(GM) are presented. Also experimental results on gain, efficiency of photon registration in the Geiger mode in the optical range of illumination, signal-noise ratio and another characteristics of the photodiode are presented. The high gain (>10ˆ5) and high efficiency of
Journal of Physics: Conference Series, 2016
Journal of Physics: Conference Series, 2016
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2006
The Silicon Photomultiplier (SiPM) is intrinsically a very fast device, its single photoelectron ... more The Silicon Photomultiplier (SiPM) is intrinsically a very fast device, its single photoelectron timing resolution is about 100 ps FWHM. Therefore real timing properties of the system scintillator+SiPM is determined mostly by timing properties of the scintillator+light collection system. We present the experimental results for timing properies of SiPM+scintillator (or Cherenkov radiator) for two cases:
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2015
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2012
ABSTRACT For about ten years the collaboration MEPhI-Max Plank Institute for Physics in Munich ha... more ABSTRACT For about ten years the collaboration MEPhI-Max Plank Institute for Physics in Munich has been developing SiPMs for the MAGIC and EUSO astro-particle physics experiments. The aim was to develop UV sensitive sensors of very high photon detection efficiency, substantially exceeding that of the classical photo multiplier tubes. For very high photo detection efficiency one needs to operate SiPM under the highest Geiger efficiency, i.e., to apply a high over-voltage. This means operating SiPM under high gain that in its turn produces a very high cross-talk. For suppressing the latter adverse effect we used isolating trenches and a second p–n junction, but also special implantation profiles and layers. We produced UV sensitive SiPMs of sizes 1 mm×1 mm and 3 mm×3 mm showing a peak Photon Detection Efficiency in the range of 50–60% at a cross-talk level of only 3–5%. One of the outstanding features of the new SiPM is their extremely low sensitivity of gain to temperature variations, amounting to 0.5%/°C. Below we report on new SiPMs.
Astroparticle, Particle, Space Physics, Radiation Interaction, Detectors and Medical Physics Applications, 2012
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2006
The Silicon Photomultipliers (SiPMs) with large area up to 10 Â 10 mm 2 are considered and their ... more The Silicon Photomultipliers (SiPMs) with large area up to 10 Â 10 mm 2 are considered and their optimal parameters, such as efficiency, gain, dark rate, afterpulsing probability and optical crosstalk are discussed. The 3 Â 3 mm 2 SiPM is described and its performance is demonstrated. Three examples of 3 Â 3 mm 2 SiPM application are given: (1) transition radiation X-ray detection; (2) time of flight measurements with fast scintillators; (3) detection of PET gammas using LYSO crystals. Corresponding experimental results are presented and discussed. r
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2018
Portable dosimeter for ambient dose equivalent (H*(10)) and ambient dose rate equivalent (Ḣ*(10))... more Portable dosimeter for ambient dose equivalent (H*(10)) and ambient dose rate equivalent (Ḣ*(10)) measurements based on Silicon Photomultiplier (SiPM) coupled to CsI(Tl) scintillator was designed and tested. Nonequivalence of the scintillator to the human tissue is corrected by the method which uses restoration of the radioactive source energy spectrum from secondary electron spectrum in scintillator. Due to that, the energy dependence response of the dosimeter is lower then 20% in range 50-3000 keV. As measured by 137 Cs nuclide sources, a dynamic range 0.1 μSv/h-10 mSv/h with a sensitivity 30 cps/(μSv/h) are achieved. Temperature stability is better then 10% in range −40-+50 • C due to combination of Zener diode and adjustment of the bias supply with DAC based on thermometer data.
2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
A coincidence timing resolution (CTR) of scintillation detectors based on SiPMs depends on both p... more A coincidence timing resolution (CTR) of scintillation detectors based on SiPMs depends on both photodetector and scintillator properties. The photodetector-related contribution is very important and has a considerable impact on the CTR. The CTR dependence on photon detection efficiency (PDE) is well studied and clarified, but as soon as advances in developments of fast scintillators and fast SiPMs make CTR approaching to a fundamental limit, a role of a single photon timing resolution (SPTR) is increased, and it requires more attention and studies. This study presents results of CTR measurements of LYSO crystals with “old” standard and timing optimized KETEK SiPM samples of 3×3 mm2 size obtained with developed digital signal processing. To complement and extend the studies on LYSO CTR with analysis on how SPTR affects multi-photon timing resolution (MPTR) with different light intensity profiles, experiments with different light sources were carried out and results were compared wit...
Journal of Physics: Conference Series, 2017
Digital signal processing (DSP) is an emerging trend in experimental studies and applications of ... more Digital signal processing (DSP) is an emerging trend in experimental studies and applications of various detectors including SiPMs. In particular, the DSP is recognized as a promising approach to improve coincidence timing resolution (CTR) of fast SiPM-based scintillation detectors. Single photon timing resolution (SPTR) is one of the key parameters affecting CTR, especially important in a case when CTR is approaching to its ultimate limits as, for example, highly demanded in Time-of-Flight PET. To study SiPM timing resolution, we developed a special DSP software and applied it to both SPTR and CTR measurements. These measurements were carried out using 3x3 mm2 KETEK SiPM samples of timing optimized and standard designs with 405 nm picosecond laser for SPTR and with 3x3x5 mm3 LYSO crystals and 511 keV Na-22 source for CRT. Results of the study are useful for further improvements of DSP algorithms and SiPM designs for fast timing.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2012
Instruments and Experimental Techniques, 2013
Dynamics of voltage recovery processes on silicon photomultipliers is experimentally and theoreti... more Dynamics of voltage recovery processes on silicon photomultipliers is experimentally and theoretically investigated. Special features of the voltage recovery in crystals with a great number of pixels are studied. Considerations on the configuration and selection of filter-element values in the supply circuit are stated. The expression for calculating the recovery time with an arbitrary number of operated pixels, taking the total number of pixels of the silicon photomultiplier, resistance value of horizontal current spreading over p- and n-regions of the pixels, and outer-element values into account, is obtained. The analytic expressions and SPICE simulation data are compared with the experimentally measured voltages across the load.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2009
One of the major drawbacks of a SiPM is due to the so-called cross-talk effect. Often, one single... more One of the major drawbacks of a SiPM is due to the so-called cross-talk effect. Often, one single photon in a chain reaction can generate more photons and thus can fire more than one micro-cell of a SiPM. This can be considered as a noise in the signal multiplication process and this degrades the signal/noise ratio. In self-trigger schemes this noise can be so high that it can make operating them difficult at low threshold settings. For the past few years, we have dwelt on this effect aiming to suppress it at the design stage. One can use (a) trenches around the micro-cells for suppressing the direct photon ''communication'' channel and (b) the so-called double p-n junction for suppressing photon-induced charge ''communication'' in neighbor pixels. The low cross-talk is mandatory, for example, for producing SiPM-based light sensor modules for the Imaging Atmospheric Cherenkov Technique projects for ground-based gamma-ray astrophysics. We produced and tested a few modules consisting of 4 SiPMs, each with a size of 5 mm  5 mm of custom production type. We report here on the main parameters of these units.
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2006
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2006
The state of art of the Silicon Photomultipliers (SiPM's)-their features, possibilities and appli... more The state of art of the Silicon Photomultipliers (SiPM's)-their features, possibilities and applications-is given. The significant progress of this novel technique of photo detection is described and discussed.
Journal of Physics: Conference Series
The technology of charged particles detection by a plastic scintillator light from which is colle... more The technology of charged particles detection by a plastic scintillator light from which is collected by wavelength shifting fiber (WLS) on Silicon Photomultiplier (SiPM) is widely used in high energy physics. We present in this article the new personnel surface contamination monitoring assembly based on that technology as a result of about two years R&D research. This assembly is used for contamination control of hands, feet and clothes at nuclear power plants, nuclear facilities and other objects that work with radioactive materials. Setup design, main parameters and its measurement procedures are presented. It has high efficiency to α and β particles in wide energy range, large dynamic range, very good area uniformity and excellent temperature stability. Dynamic range of measured particle fluence rate equals: 1 – 106 Hz·cm2·min for β-module and 0.1 – 2·104 Hz·cm2·min for α-module. Variations of the module response in temperature range from –20 C up to +50 C doesn`t exceed 3%.
A coincidence timing resolution (CTR) of scintillation detectors based on SiPMs depends on both p... more A coincidence timing resolution (CTR) of scintillation detectors based on SiPMs depends on both photodetector and scintillator properties. The photodetector-related contribution is very important and has a considerable impact on the CTR. The CTR dependence on photon detection efficiency (PDE) is well studied and clarified, but as soon as advances in developments of fast scintillators and fast SiPMs make CTR approaching to a fundamental limit, a role of a single photon timing resolution (SPTR) is increased, and it requires more attention and studies. This study presents results of CTR measurements of LYSO crystals with “old” standard and timing optimized KETEK SiPM samples of 3×3 mm2 size obtained with developed digital signal processing. To complement and extend the studies on LYSO CTR with analysis on how SPTR affects multi-photon timing resolution (MPTR) with different light intensity profiles, experiments with different light sources were carried out and results were compared with an analytical model of SiPM timing resolution.
Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment - NUCL INSTRUM METH PHYS RES A, 2003
The Silicon Photomultiplier (SiPM) is a semiconductor device consisting of many photon microcount... more The Silicon Photomultiplier (SiPM) is a semiconductor device consisting of many photon microcounters (103mm−2) positioned on a common Si substrate. SiPM operates in a limited Geiger mode and has single photoelectron gain (106) and photon detection efficiency (20%) similar to vacuum PMT. Main SiPM features are described and a number of examples of its possible applications are demonstrated, such as scintillator fiber readout, scintillator tiles+WLS readout, imaging Cherenkov counter timing. These SiPM applications are based on experimental test data and SiPM performance is compared with other photodetectors (PMT, APD, HPD, VLPC).
At present the development of a silicon photomultiplier (SiPM), being a microcell photodiode with... more At present the development of a silicon photomultiplier (SiPM), being a microcell photodiode with Geiger amplification, is going on [1]. Such devices are capable of registering faint light bursts, what, in aggregate with their small dimensions, makes them highly promising for application as photoreceivers in scintillation fiber detectors. Relying on the studies of the latter and those of SiPM, a bread-board model of a tracking detector of relativistic particles, containing 16 channels, has been designed and created. The characteristics of SiPM have been studied with a beta-source. A read-out electronic unit, containing preamps, shapers, discriminators, has been designed to collect the signals of SiPM. The characteristics of this unit are presented and the prospects of its application in experimental physics are discussed.
2000 IEEE Nuclear Science Symposium. Conference Record (Cat. No.00CH37149), 2000
The new design, principle of operation, and physical processes in a microcell Si avalanche photod... more The new design, principle of operation, and physical processes in a microcell Si avalanche photodiode with limited Geiger mode gain muCAPD(GM) are presented. Also experimental results on gain, efficiency of photon registration in the Geiger mode in the optical range of illumination, signal-noise ratio and another characteristics of the photodiode are presented. The high gain (>10ˆ5) and high efficiency of
Journal of Physics: Conference Series, 2016
Journal of Physics: Conference Series, 2016
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2006
The Silicon Photomultiplier (SiPM) is intrinsically a very fast device, its single photoelectron ... more The Silicon Photomultiplier (SiPM) is intrinsically a very fast device, its single photoelectron timing resolution is about 100 ps FWHM. Therefore real timing properties of the system scintillator+SiPM is determined mostly by timing properties of the scintillator+light collection system. We present the experimental results for timing properies of SiPM+scintillator (or Cherenkov radiator) for two cases:
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2015
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2012
ABSTRACT For about ten years the collaboration MEPhI-Max Plank Institute for Physics in Munich ha... more ABSTRACT For about ten years the collaboration MEPhI-Max Plank Institute for Physics in Munich has been developing SiPMs for the MAGIC and EUSO astro-particle physics experiments. The aim was to develop UV sensitive sensors of very high photon detection efficiency, substantially exceeding that of the classical photo multiplier tubes. For very high photo detection efficiency one needs to operate SiPM under the highest Geiger efficiency, i.e., to apply a high over-voltage. This means operating SiPM under high gain that in its turn produces a very high cross-talk. For suppressing the latter adverse effect we used isolating trenches and a second p–n junction, but also special implantation profiles and layers. We produced UV sensitive SiPMs of sizes 1 mm×1 mm and 3 mm×3 mm showing a peak Photon Detection Efficiency in the range of 50–60% at a cross-talk level of only 3–5%. One of the outstanding features of the new SiPM is their extremely low sensitivity of gain to temperature variations, amounting to 0.5%/°C. Below we report on new SiPMs.
Astroparticle, Particle, Space Physics, Radiation Interaction, Detectors and Medical Physics Applications, 2012
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2006
The Silicon Photomultipliers (SiPMs) with large area up to 10 Â 10 mm 2 are considered and their ... more The Silicon Photomultipliers (SiPMs) with large area up to 10 Â 10 mm 2 are considered and their optimal parameters, such as efficiency, gain, dark rate, afterpulsing probability and optical crosstalk are discussed. The 3 Â 3 mm 2 SiPM is described and its performance is demonstrated. Three examples of 3 Â 3 mm 2 SiPM application are given: (1) transition radiation X-ray detection; (2) time of flight measurements with fast scintillators; (3) detection of PET gammas using LYSO crystals. Corresponding experimental results are presented and discussed. r