| Family name | Given name | Affiliation | Presentation style | Title | Authors | Abstract |
|---|---|---|---|---|---|---|
| Otani | Masashi | Kyoto University | oral | The first large application of MPPC:The T2K neutrino beam | Masashi Otani | The T2K neutrino beam monitor INGRID(Interactive Neutrino GRID) is the first large application of MPPC(Multi Pixel Photon Counter) for real physics experiment. The T2K long baseline neutrino oscillation experiment will start from April 2009. In T2K, because of the off-axis beam scheme that correlates the beam direction with the neutrino energy spectrum at the far detector, the neutrino beam direction needs to be monitored with precision better than 1 mrad. INGRID will monitor the neutrino beam direction and stability. INGRID is located 280m downstream of the proton target, at the center of the neutrino beam. INGRID consists of 16 modules which is neutrino target and neutrino detector. Each module is a sandwich of nine iron target planes and eleven scintillator tracking planes. By counting the number of muons from neutrino interactions in each module, the neutrino beam profile is reconstructed and the beam center is determined. The light from scintillator is read by MPPC via wavelength shifting fibers. We have measured the performance of prototype detectors and confirmed that the detector has more than 99.5% efficiency for MIP as required. The total target mass of INGRID is 116 ton and the number of total MPPC is 9,592. At the commissioning stage INGRID will be used to tune and confirm the neutrino beam direction. INGRID will monitor the beam direction and the stability of beam quality on daily basis when the beam power increases. The INGRID detector has been constructed and installed into the detector hall. Now we are in the stage of beam commissioning. Design and commissioning status of the INGRID detector will be presented. |
| Nio | Daisuke | The Graduate University for Advanced Studies | oral | Feasibility study of Si APD detector using SOI technology | Daisuke NIO, Yauo ARAI | We have been developing the SOI (Silicon On Insulator) pixel detectors, which is monolithic detectors including sensors and circuitry. With SOI technology, we can avoid mechanical bonding between sensors and circuitry, so we can expect faster and more compact detectors. We have already succeeded in getting good performance for sensing visible light, X-ray and charged particle. To extend the possibility of the SOI pixel detectors, we have started a feasibility study to realize silicon avalanche photodiodes (Si APD) as the sensor. We have done the simulation by using a TCAD (Technical CAD) simulator. The possibility of realizing the silicon avalanche photodiodes in the SOI pixel detector will be presented. |
| Kurosawa | Shunsuke | Department of Physics, Graduate School of Science, Kyoto University | oral | A Novel Position-Sensitive Radiation Detector Using a Gaseous Photomultiplier and an UV Scintillator | Shunsuke Kurosawa, Hidetoshi Kubo, Toru Tanimori (Kyoto Univ.), Hiroyuki Sekiya (ICRR, The University of Tokyo), Kentaro Fukuda, Sumito Ishizu, Noriaki Kawaguchi, Toshihisa Suyama (Tokuyama Corporation), Akira Yoshikawa, Takayuki Yanagida, Yuui Yokota (IMRAM, Tohoku University) | We have developed a novel position-sensitive radiation detector that consists of a large-size position-sensitive gaseous photomultiplier with an ultraviolet (UV) sensitive CsI photocathode and an UV scintillator. Although the UV detector itself can be applied to material analysis and to liquid Ar/Xe scintillators, in order to obtain hard X-ray image with higher detection efficiency than gaseous detectors, we have used an UV scintillator. Our prototype gaseous detector consists of a MgF2 window with a transmissive CsI photocathode layer, two Gas Electron Multipliers(GEMs), and a position-sensitive gaseous detector named Micro Pixel Chamber (mu-PIC). The detector was filled with argon (90%) and ethane gas (10%) at 1 atm. The GEMs and mu-PIC had effective areas of 10x10 cm^2. The UV scintillator, LaF(Nd), with a volume of 2x2x2 cm^3 was coupled to the MgF2 window. We succeeded in obtaining images by irradiating 5.5 MeV alpha particles from a Am-241 source to the LaF(Nd). |
| Haigh | Martin | University of Warwick, UK | oral | Monte Carlo simulation of MPPC photosensors for the T2K experiment | M Haigh (University of Warwick), F Retiere (TRIUMF), A Vacheret (Imperial College London) | A Monte Carlo model of the MPPC photosensor has been developed by the T2K-ND280 collaboration, forming part of the detector readout chain simulation. This model incorporates all device features, including dark noise, crosstalk, afterpulsing and saturation, and also includes recovery effects specific to the ND280 front-end readout circuit. Simulation parameters have been tuned using the results of characterization measurements made by the collaboration. This talk outlines the framework and physics models used in the simulation, and results from the Monte Carlo are compared to data. |
| Mizumura | Yoshitaka | Department of Physics, Tokai University | poster | Basic study of PPD for the next generation of IACTs | Yoshitaka Mizumura, Kazuhito Kodani, Junko Kushida, Kyoshi Nishijima | The PPD is a novel photon-counting device made up of multiple APD pixels operated in Geiger mode. We started the research for the possibility of applying PPDs to the next generation of Imaging Atmospheric cherenkov Telescopes. As first step, we measure the response of 1mm x 1mm size and 3mm x 3mm size samples of MPPC, which is one of the PPDs manufactured by Hamamatsu, and study the basic characteristics. |
| Tadday | Alexander | University of Heidelberg | oral | Characterization Studies of Silicon Photomultipliers for a Calorimeter for the ILC | Alexander Tadday, Patrick Eckert (University of Heidelberg), Kolja Prothmann (MPI Munich) | The analog hadronic calorimeter for the International Linear Collider, developed by the CALICE Collaboration, uses novel silicon pixel-detectors (Silicon Photomultipliers) for the readout of small organic scintillator tiles. In the work presented here, a test-setup has been developed which allows to measure and compare the properties of these sensors. Besides the general characterization of the devices like the estimation of the working point, the setup features a measurement of the Photon-Detection-Efficiency over a wide spectral range. Further it is possible to systematically study the overall device uniformity by illumination of small areas of the sensor, using a pulsed light-source. Results of these measurements for different sensor-models are presented and compared. In addition, measurements of the device response, of afterpulsing and of pixel to pixel crosstalk performed with very short laser pulses will be discussed. |
| Naito | Daichi | Kyoto University | poster | Study of parallel-connected MPPC readout scheme | Daichi Naito, Noboru Sasao, Tadasi Nomura, Hajime Nanjo, Hideki Morii, Koji Siomi, Naoki Kawasaki, Takahiko Masuda, Yosuke Maeda | The KOTO experiment, planned to be carried out at the J-Parc 50-Gev PS, is a dedicated experiment to search for the CP-violating rare decay mode K--> pi^0 nu nu. The standard model prediction of its branching fraction is 2.5 x 10^{-11}; obviously the key to success is background rejection. In the experiment, we plan to use a plastic scintillator as a veto counter; its role is to reject various K-decay modes involving charged particles. This counter, called CV(Charged Veto), must detect an energy deposit as low as 100keV. To realize this, we use multi-pixel photon counters(MPPC) as a photo-sensor in conjunction with wavelength shifting fibers. The merit of MPPCs is their high detection efficiency. About 1600 channels are needed in total, and 8 MPPC outputs are connected together and are read as one to reduce the readout channels. One of the disadvantages of this readout scheme is that their effective output pulse becomes wider as the number of parallel-connected MPPC increases. We report results of the study on this phenomena and present a method to overcome the pulse widening. |
| Ieki | Kei | Kyoto Univ. | oral | MPPC for T2K Fine-Grained Detector | K Ieki, T Nakaya, M Yokoyama(Kyoto Univ.), S Oser, H Tanaka, F Retiere, T Lindner(TRIUMF) | The FGDs (Fine-Grained Detectors) are a part of the T2K near detector which will detect particle tracks from neutrino interactions to measure the initial neutrino beam flux, flavour, and energy prior to neutrino oscillation effects. It is constructed as an array of scintillator bars which are read out by MPPCs via wavelength-shifting fibers. We have integrated all 8448 channel of MPPCs and tested the read out electronics in beam tests at TRIUMF. Finally, it will be installed this autumn to start data-taking in the winter. I will briefly talk about MPPC integration on the FGD, the readout electronics, and the MPPC performance in the beam test. |
| Lee | Chaehun | KAIST | poster | Development of SiPM with Electric Field Confining Structure | Chaehun Lee, Hyoung-taek Kim, Jinkyu Kim, Bokyung Cha, Junhyung Bae, and Gyuseong Cho | SiPMs have many application fields such as PET-MRI fusion imaging, molecular fluorescence, neutron measurements, and high energy physics. A SiPM is a promising sensor to replace PMT, but the performances of SiPMs such as PDE, dynamic range, and dark count rates have to be improved. In this study, a SiPM with a new doping structure was designed and fabricated. Avalanche triggering probability depends on applied bias, and e-h impact ionization coefficient which is a function of electric field. SiPMs usually have a doping structure of. In order to increase the electric field of avalanche region in SiPM, a n+/p-/p/pi/p+ doping structure to confine the electric field of avalanche region was proposed. A thin p layer having a higher doping concentration than p- layer is inserted between the p- and pi layer. It will expand the high electric field region triggering avalanche at the same applied voltage of n+ /p/pi/p+ doping structure. In this doping structure, the electric field is confined in p region, so mean electric field in avalanche region is relatively higher than n n+/p/pi/p+ structure. Doping concentration, Implant condition was modeled with TCAD simulation. 2 mm x 2 mm prototype SiPMs having poly silicon quenching resistors were fabricated on 4 um epitaxial wafers and packaged with metal cans. Performance such as gain, PDE and dark count rates were evaluated and compared to n+/p/pi/p+ structure. Gamma spectroscopic test was also done with a LYSO scintillation crystal. |
| Nishida | Shohei | KEK | oral | Study of 144ch HAPD for Aerogel RICH for Belle upgrade | S. Nishida | For upgrade of the Belle detector at KEKB collider, we are developing a proximity focusing ring imaging Cherenkov detector using aerogel as a radiator (Aerogel RICH). One of the candidate photo-detector is a 144ch multi-anode HAPD (Hybrid avalanche photo-detector) developed with Hamamatsu Photonics K.K. (HPK). We report the performance of HAPD, and the result of the beam test using 6 HAPDs. |
| Kuroda | Eiryo | Tokyo Metropolitan University | poster | Readout of 144ch HAPD for Aerogel RICH for Belle upgrade | Eiryo Kuroda | For upgrade of the Belle detector at KEKB collider, we are developing a proximity focusing ring imaging Cherenkov detector using aerogel as a radiator (Aerogel RICH). One of the candidate photo-detector is a 144ch multi-anode HAPD (Hybrid avalanche photo-detector) developed with Hamamatsu Photonics K.K. (HPK). We have been developing the ASIC for readout of HAPD output.We present the performance of the ASIC and status of its development. |
| Murase | Takuro | Department of Physics, University of Tokyo | oral | Development of PPD: characterization and simulation | Takuro Murase, Hideyuki Oide, Hidetoshi Otono, Satoru Yamashita, on behalf of KEK Detector Technology Project | In this talk, we report measurement results of the noises of MPPC, a Pixelated Photon Detector (PPD) produced by HPK, and a current status of simulations of PPD with Toy-MC and device simulator T-CAD. Total noise rate of MPPC at high operational voltage is investigated and the combined effects of various noises are evaluated quantitatively. Simulations are performed to look into the origin of the noises and to reproduce basic characteristics of MPPC. |
| Kotera | Katsushige | Shinshu university | poster | Application of MPPC to granular electromagnetic calorimeter for ILC | Katsushige Kotera, Shinshu university for for GLD calorimeter Group, CALICE | MPPC has advantages to make a large and granular sensitive calorimeter. As an application of 1600 pixel MPPC, we will show the performance of our prototype electromagnetic calorimeter for International Linear Collider; stacking 30 layers of scintillator pad paved with 72 finger size strip-scintillators, 1 cm x 4.5 cm x 0.3 cm. Each strip-scintillator is readout by MPPC. Consequently, the calorimeter consists of 2160 strip-scintillator channels with MPPCs. We tested this compact calorimeter, 18 cm x 18 xm x 25 cm, with 1 -32 GeV electron beam and 2 - 60 GeV pion beam at Fermi National Accelerator Laboratory in 2008 and 2009. Linearity and uniformity of responses and energy resolution will be presented. |
| Tachimoto | Takuto | Osaka university | oral | study of electromagnetic calorimater for COMET | Takuto Tachimoto | We have been developing electromagnetic calorimeters for the COMET and PRISM/PRIME experiment. The calorimeter demands a fast response (τ<100nsec) and high energy resolution (<5%). To accomplish it, we develop the calorimeter system, which consists of LYSO crystals, MPPCs (Multi pixel photon counter) and light guides. A MPPC is directly connected to a crystal using a light guide. On this presentation, I will talk about the performance of this type of calorimeter, which is estimated by Monte Carlo simulation. |
| Nakadozono | Naoyuki | Osaka university | oral | R&D on a gating PMT of Proton Extinction Monitor | Nakadozono Naoyuki | We have proposed an experiment called "COMET (COherent Muon to Electron Transition)" to search for a muon to electron conversion process at J-PARC. In order to avoid the backgrounds related to primary protons, we make use of a pulsed proton beam. The repetition of proton pulses is about 1 MHz, and each proton pulse contains 10^8 of 8-GeV protons. In order to achieve 10^(-16) of branching ratio for muon to electron conversion, a number of protons coming between pulses must be less than 10^(-9) to that coming in a main pulse. This ratio is called "proton extinction". We are developing a device to monitor the proton extinction. The proton extinction monitor under my study consists of gas Cherenkov detector with gating photomultiplier tubes (PMT). In order to make it sensitive to 8-GeV protons, Cherenkov radiator gas will be pressured up to 20 atm. Cherenkov lights emitted by primary protons are detected by the gating PMT. The H.V. of the gating PMT is switched at a high frequency such as a MHz to avoid saturation of the PMT from main proton pulses. An electric circuit required for this requirement is designed and tested. A prototype of the gating PMT was fabricated, and the on/off ratio of 10^(-6) has been achived. |
| Okada | Kyoko | SPring-8/JASRI | poster | Feasibility study of applying APD for synchrotron soft x-ray measurements | Kyoko Okada, Tetsuya Nakamura, Shunji Kishimoto, Masakiyo Tsunoda, Taizo Kawauchi, Kenji Kodama, Yoshimasa Urushihara, Tomohiro Matsushita, Yoshiharu Sakurai | We have developed APD (Avalanche PhotoDiode) photon counting system for soft x-ray experiments at SPring-8, the 3rd generation synchrotron radiation facility. APD detectors for hard x-ray are widely used at synchrotron radiation facilities taking advantages of the high time-resolution and the wide dynamic-range. However, the present APD doesn't cover soft x-ray region of below 2 keV. The purpose of the present study is, therefore, to develop a new APD detector especially for soft x-rays below 1keV, where the sensor has to be installed in ultra high vacuum. The lower noise level and the higher gain are required as the technical subject to achieve in the development. As the result, we have succeeded in detecting the soft x-rays of above 0.5 keV and have observed x-ray bunch structures of 23.4 ns intervals with time resolution of 0.4 ns. In addition, a soft x-ray magnetic circular dichroism measurement in a MnIr/FeCo exchange-coupled epitaxial bilayers sample in transmission geometry has also demonstrated. |
| Yamamura | Kazuhisa | HAMAMATSU PHOTONICS K.K. | oral | Products and Development Status of MPPC | Kazuhisa Yamamura, Kenichi Sato, Shogo Kamakura, Shinji Ohsuka | The MPPC (Multi-Pixel Photon Counter) is a solid state device made up of multiple APD (Avalanche Photo Diode) pixels operated in Geiger mode. MPPC have excellent photon counting capability at room temperature. Hamamatsu Photonics released single channel devices having the active area of 1x1mm and 3x3mm and array devises having 4 or 16 channels. And we are developing low noise MPPC with a thermoelectrically cooler. As a good blue sensitivity, MPPC is well matched to detect the week emission light of scintillators for HEP or medical applications. For example, T2K experiment adopted MPPCs, and we have delivered 60Kpcs of 1.3x1.3mm-MPPCs. In mass production, we confirmed that the characteristic of MPPCs are very uniform between lot to lot. And as a good timing resolution and insensitive to magnetic field, MPPC is expected to use for the MRI-PET and TOF-PET detectors. For PET application, we are now evaluating energy resolution and timing resolution of 3x3mm MPPC coupled with LYSO. And we are measuring the response characteristic of each pixels in MPPC chip and studying the relationship between resistance of trace electrode and timing resolution. The evaluation result will be explained. |
| Brekke | Njaal | University of Bergen | oral | Comparison of different pixelated APD technologies and light yield study of 3mm scintillator tiles | Njaal Brekke, Gerald Eigen, Dieter Roehrich, Hege Austrheim Erdal, Renate Gruner, Dominik Fehler, Heidi Sandaker, Lars-Halvard Helleve | Pixelated APDs operating in the Geiger mode provide a novel readout for calorimeters in ILC detectors, SuperB neutrino experiments and PET detectors. We have studied properties of four different detector technologies (MePhi SiPMs, MPPCs, MAPDs and MRS APDs) including gain, dark rate, rise time, cross talk and after pulsing. We have coupled SiPMs and MPPCs to directly and via wavelength shifting fibers to 3mm thick scintillator tiles to study light yield and uniformity. Furthermore, we have studied cross talk for two adjacent sector-shaped strips that are connected via small bridges to provide mechanical stability. This is a crucial issue for an electromagnetic Pb-scintillator sampling calorimeter considered as a backward endcap for SuperB. |
| Kurjata | Robert | Warsaw University of Technology, Institute of Radioelectronics | oral | A system for automated measurement of parameters of large quantities of MPPC detectors | Michal Dziewiecki, Marcin Ziembicki, Robert Kurjata, Robert Sulej, Janusz Marzec, Krzysztof Zaremba | A new system for fully automated parameter measurements of large quantities of MPPC detectors has been developed. The aim of the project was to create a compact, portable device allowing measurement of gain, breakdown voltage, PDE (relative), dark rate, and cross-talk & afterpulse ratio, with minimum operator interaction required. The system consists of two parts: a 32-slot, temperature-controlled MPPC feeder with integrated pre-amplifier and LED flasher and an electronics box with a pulse shaper, a high-speed ADC with on-board FPGA, a two-threshold discriminator, a slow-control unit, a network interface and a power supply. An effort has been made to minimize noise and external interference, as well as to achieve good stability of MPPC supply voltage and temperature. The whole system is controlled via Ethernet network by accompanying software, which also performs on-the-fly data analysis. |
| Kraehenbuehl | Thomas | ETH Zurich | oral | Geiger-mode avalanche photodiodes as photodetectors in Cherenkov astronomy | Thomas Kraehenbuehl for the FACT project | The progress in the development of Geiger-mode avalanche photodiodes (G-APD) has resulted in devices which show great promise for Imaging Atmospheric Cherenkov Telescopes (IACT). In the course of the First G-APD Camera Test (FACT) project, with the purpose to construct a G-APD based camera foreseen for the DWARF telescope, their characteristics are analyzed and measured in detail. Several properties are found to be favorable compared to photomultiplier tubes, such as the higher photon detection efficiency, the angle-independent sensitivity and the different timing characteristics of afterpulses. The effects of saturation and cross-talk on the reconstruction of the number of detected photons are studied. |
| Korpar | Samo | University of Maribor | oral | RICH photon detector module based on Geiger-mode APDs | Samo Korpar, Hassan Chagani, Rok Dolenec, Peter Krizan, Rok Pestotnik, Ales Stanovnik | A module was constructed, consisting of 64 (=8x8) Hamamatsu MPPC S10362-11-100P Geiger-mode APDs, for position sensitive detection of Cherenkov photons. Suitable light concentrators were produced to increase the efficiency and to improve the signal to noise ratio. We have tested the module in combination with aerogel radiator in a proximity focusing configuration. The results of our measurements show that such a module can be used for detection of single photons in a ring imaging Cherenkov detectors such as the counter foreseen for the upgrade of the Belle detector. |
| Kim | Chang | GE Global Research Center | oral | Pulse Shapes of Solid State Photomultiplier and its importance for Time-of-Flight PET | Chang L. Kim | Pulse shape, photon-detection efficiency, dark counts, temperature and bias, were identified as critical factors affecting timing resolution after an extensive measurement of solid-state photomultipliers (SSPM) for time-of-flight PET. Among those factors, pulse shape has been investigated in detail through SPICE simulation and the measurement of single photon pulse shape. Pulse shapes of Multi-Pixel Photon Counter (MPPC) from Hamamatsu Corp. were measured for 25um, 50um and 100um micro-cells with both 1x1mm2 and 3x3mm2 devices. Various high bandwidth amplifiers with different slew rates and noises, Hamamatsu C5594 (1.5GHz), ORTEC 9327(1GHz), Mini-circuit ZX60_4016E (4GHz), Texas Instruments THS4303 (1.8GHz), were used on a 4GHz bandwidth oscilloscope and its results were compared to SPICE simulations. SPICE model was based on a capacitance of a single micro-cell, passive quenching resistor, parasitic capacitance of quenching resistor, number of micro-cells. From the comparison, we will show several ways to improve the recovery time of SSPM and explain how parasitic capacitance of quenching resistor can be utilized. In summary, we will show how the improvement of single photon pulse shape is related to a fast rise time of 511keV LYSO pulse shape and its impact to coincidence timing resolution in order to achieve TOF PET using SSPM under 250ps. |
| JRADI | Khalil | CESR | oral | Study, simulation and manufacturing of new Geiger-APD for applications in Astrophysics and Biology | K. JRADI, D. PELLION, T. CAMPS, A. LEPADELLEC, F. MOUTIER, A.R. BAZER-BACHI | Abstract Nowadays, there are two types of sensors to detect the low luminous flux, PMT (PhotoMultiplier Tube) and Geiger-APD. The Geiger-APD is a component on silicon that was developed in the early 90s to detect very low light flux, as is currently the PMT (PhotoMultiplier Tube). The main advantages of these devices on the PMT are a very high sensitivity to light (one photon), a very important time resolution (<100ps) and integration into imaging made possibly by a great homogeneity. Unfortunately, these components are weak compared to PMT, a very small sensitive area (20μm) and a leakage current (Dark Count Rate) higher per unit area. A first technological process has already been studied in collaboration between the CESR and the LAAS to develop chain technology components called "Geiger-APD" or "SiPM. The second work to be done includes the integration into Microsystems, with ambition, in long term, to develop several applications in astrophysics, biology, optical detection, and most essentially, fast imaging systems. The manufacturing of imaging equipment in a new process must be defined by a detailed study on the imaging Geiger. Different applications in astrophysics are possible such as the detection of Cerenkov flash. |
| Blazej | Josef | Czech Technical University in Prague | poster | Signal strength monitoring in avalanche structures operated in Geiger mode | Josef Blazej, Ivan Prochazka | We are presenting recent results of experimental analysis of avalanche build-up process in various silicon avalanche structures. Structures has been operated in Geiger mode controlled by active gating and passive quenching circuit. Measurable changes in avalanche rapidity allow us to monitor optical signal strength in few-photon region 1 - 1000 photons. The resolution, reproducibility and dynamical range of these shot-by-shot based measurements will be discussed. The figure of merit of photon number resolution related with detection temporal resolution and other experimental aspects will be compared for single- and multi-pixel detectors. |
| Mirzoyan | Razmick | Max-Planck-Institute for Physics | oral | Large Area Silicon Photomultipliers: Scintillation Spectroscopy and Timing Properties | R. Mirzoyan, B. Dolgoshein, P. Buzhan, S. Klemin, H. Miyamoto, E. Popova, M. Teshima | For a good amplitude and timing resolutions a SiPMs shall have a low Excess Noise Factor (ENF) not exceeding the level of a few %. The ENF is mostly defined by the distortion of Poisson distribution of the number of micro-cells that (additionally) fire due to inter-pixel optical cross-talk (OC). There are two reasons for such an OC a) secondary photons created in a Geiger discharge inside a given micro-cell can fire other micro-cells (so called internal OC: IOC), b) secondary photons are reflected back from outside of the SiPM body, e.g. reflected back from an attached scintillation crystal or from the protective layer of the entrance window (so called external OC: EOC). Both IOC and EOC are especially important for large area SiPMs of high (>= 50%) Photon Detection Efficiency (PDE). These have a large pixel size and as a consequence high gain (~10^7). We have studied both the IOC and the EOC in detail and developed methods for the OC suppression for a SiPM of a size of 5x5 mm^2, gain 2x10^7 and high PDE. The results of those studies will be presented. The impact of the OC suppression on low energy (down to 14 KeV Am 241 photons) scintillation spectroscopy (SiPM + LYSO crystal) will be demonstrated. In addition the timing resolution of different area SiPMs (1x1, 3x3 and 5x5 mm^2) have been studied. The dependence of the SiPM size on timing properties will be presented. |
| Renker | Dieter | Paul-Scherrer-Institute | oral | Properties of state of the art Geiger-mode avalanche photodiodes | Dieter Renker | After 10 years of development Geiger-mode Avalanche Photo Diodes (G-APDs, also called SiPM, MPPC etc.) have reached maturity but there is still room for improvements. Devices from several producers with different properties are available. The state of the art will be reported, the general properties specified and the problems described. An attempt to look for future prospects will be done. |
| Sudo | Yuji | University of Tsukuba | oral | Study of the Multi-Pixel Photon Counter for the ILC Scintillator-Strip Calorimeter | Yuji Sudo, for the GLD Calorimeter Group / KEK DTP Project Photon Sensor Group | For the ILC experiment, we are developing and studying the finely segmented scintillator-strip calorimeter which is called ScECal. The Multi-Pixel Photon Counter (MPPC), manufactured by Hamamatsu Photonics, is a prime candidate for the photon sensor. Currently we are developing and studying the 1600-pixel MPPC with 1x1 mm^2 sensor area. In this presentation we'll report the performance of the MPPC obtained from those studies. Since the recovery time of 1600-pixel MPPC is known to be short (about 4 ns), each pixel can fire multiple times for the light from scintillator-strip through wavelength-shifting fibers. Although this effect is usuful, the total response of the MPPC is saturated for high intensity light. Therefore a large number of pixels is still necessary for ScECal readout. Secondly, understandin radiation tolerance of the MPPC is importand for any high energy experiment. We have irradiated the MPPC with gamma-rays and neutrons to investigate the radiation damage. |
| Koji | Miwa | Tohoku University | oral | Active Target System with MPPC Readout for Hyperon-Proton Scattering Experiment | K.Miwa, R.Honda, K.Hosomi, T.Koike, Y.Ma, T.Otani, M.Sato, K.Shirotori, H.Tamura, T.Yamamoto, T.Yomemoto | We are developing a Scifi active target system with MPPC readout for a hyperon-nucleon(YN) scattering experiment at J-PARC. At J-PARC, we will use high-intensity meson beams to produce hyperon beams in the active target. The active target should work under such beam condition. Because MPPC is a fast device and it can operate in a magnetic field, we selected the MPPC for the readout. In order to check the feasibility of the active target using MPPC readout, we made a small prototype which consisted of 36 scintillation fibers read by MPPC, and performed some test experiments using 600 MeV positron and 20 ~ 40 MeV proton beams. The mean photon numbers for positron and proton are about 7 and 120, respectively. The trajectories of both positron and proton are clearly identified. The range of proton in the target corresponds the energy of the proton beam. From these studies, we have found that the active target fulfills the basic requirements for the YN scattering experiment. Recently, we have performed a proton scattering experiment using this target system for further study. The system worked well under a rather high counting rate (~50kHz) and proton-proton scattering events are clearly identified. We would like to talk about the development status of our active target and results obtained from these test experiments. |
| Orme | Daniel | Department of Physics, Kyoto University | oral | Measurement of the PDE of MPPCs with different wavelengths of light | D. Orme, A. Minamino, T, Nakaya, M. Yokoyama | We have performed measurements of the Photon Detection Efficiency (PDE) of Multi-Pixel Photon Counters (MPPCs) illuminated with different wavelengths of light. Since photons of different wavelengths will penetrate the silicon layer of the MPPC to different depths, we expect that the voltage dependence of the PDE may differ with wavelength. If so, then some information about the internal structure of the MPPC can be gained. The results and conclusions of these measurements will be presented in this talk. |
| Retiere | Fabrice | TRIUMF | oral | Using MPPCs for T2K near detector | Fabrice Retire for T2K collaboration | T2K near detector is designed to characterize the neutrino beam produced by the J-PARC accelerator complex in Tokai (Japan), as well as to study neutrino cross-sections. 5 detector element are assembled from similar building blocks: an extruded scintillator bar with a wavelength shifting fiber running through the hole, readout on one or both ends by a Multi Pixel Photon Counter from Hamamatsu Photonics. In total about 50,000 are about to be operated by the end of 2009. In this talk, we will review the tasks that were and are being tackled by the T2K collaboration in order to deploy such a large number of sensors: 1) careful characterization and subsequent simulations of the MPPCs, 2) quality assurance, 3) design and construction of the readout electronics, and 4) operation and calibration of the devices. |
| Yamazaki | Makoto | Department of Science, Shinshu University | poster | Study of LFS inorganic scintillator for applying to PET with 1x1mm2 MPPC | Makoto Yamazaki, Tohru Takeshita | The main challenges in the design of next generation Positron Emission Tomography machines are the improvement of the spatial resolution and the combined operation with magnetic resonance. The Multi Pixel Photon Counter by Hamamatsu is a good candidate for this application, especially referring to newly developed size. Its small size (1x1 mm2 and 3x3 mm2) and high photo detection efficiency in the blue spectral region allows the direct readout of a highly segmented scintillator matrix with improvements on the detector's spatial resolution. Furthermore, this photodetector is insensitive to magnetic fields up to 5 T, making its application in a magnetic resonance environment possible. The aim of the study presented is the characterization of a system of scintillator crystal readout via MPPC. Crystal of 3x3x15mm3 are directly coupled to a MPPC of the same size active area, and the energy resolution at 511 keV is measured to recognize possibility that we could use that system for PET. In addition, we measured the characters of LFS (Lutetium Fine Silicate from Zecotek in Canada) compared with present general scintillators such as BGO. In this experiment, we got the larger number of photons than traditional inorganic scintillators on LFS which was attached to MPPC. In addition to that, I am going to recognizing difference between two kinds of set up, LFS & 1x1mm2MPPC and LFS & 3x3mm2MPPC, and the spatial resolution by the coincidence experiment will be reported to confirm whether we could apply the system to PET machine. I hope spatial resolution could be better than existent PET device according to experiment which I am doing now. |