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Sample records for hybrid photomultiplier tubes

  1. photomultiplier tube

    CERN Multimedia

    photomultiplier tubes. A device to convert light into an electric signal (the name is often abbreviated to PM). Photomultipliers are used in all detectors based on scintillating material (i.e. based on large numbers of fibres which produce scintillation light at the passage of a charged particle). A photomultiplier consists of 3 main parts: firstly, a photocathode where photons are converted into electrons by the photoelectric effect; secondly, a multiplier chain consisting of a serie of dynodes which multiply the number of electron; finally, an anode, which collects the resulting current.

  2. photomultiplier tubes

    CERN Multimedia

    photomultiplier tubes. A device to convert light into an electric signal (the name is often abbreviated to PM). Photomultipliers are used in all detectors based on scintillating material (i.e. based on large numbers of fibres which produce scintillation light at the passage of a charged particle). A photomultiplier consists of 3 main parts: firstly, a photocathode where photons are converted into electrons by the photoelectric effect; secondly, a multiplier chain consisting of a serie of dynodes which multiply the number of electron; finally, an anode, which collects the resulting current.

  3. photomultiplier tube

    CERN Multimedia

    A device to convert light into an electric signal (the name is often abbreviated to PM). Photomultipliers are used in all detectors based on scintillating material (i.e. based on large numbers of fibres which produce scintillation light at the passage of a charged particle). A photomultiplier consists of 3 main parts: firstly, a photocathode where photons are converted into electrons by the photoelectric effect; secondly, a multiplier chain consisting of a serie of dynodes which multiply the number of electron; finally, an anode, which collects the resulting current.

  4. photomultiplier tube

    CERN Multimedia

    Philips. 150AVP. A device to convert light into an electric signal (the name is often abbreviated to PM). Photomultipliers are used in all detectors based on scintillating material (i.e. based on large numbers of fibres which produce scintillation light at the passage of a charged particle). A photomultiplier consists of 3 main parts: firstly, a photocathode where photons are converted into electrons by the photoelectric effect; secondly, a multiplier chain consisting of a serie of dynodes which multiply the number of electron; finally, an anode, which collects the resulting current.

  5. X-ray detection with a scintillating YAP-window hybrid photomultiplier tube

    CERN Document Server

    D'Ambrosio, C; Leutz, H; Puertolas, D; Rosso, E

    2000-01-01

    A YAP(YAlO/sub 3/:Ce)-scintillating window, coated on its inner surface with an S20-photocathode, seals a cross-focusing hybrid photomultiplier tube (HPMT) equipped with a small p-i-n anode of 2-mm diameter. This new radiation detector separates X-ray lines down to about 2-keV peak energy from the HPMT noise. Its detection efficiency for high gamma energies depends on the YAP-window thickness and amounts to about 18% attenuation at 400-keV energy in the present version. Competitive radiation detectors like Si photodiodes and Si drift chambers are discussed and compared to our prototype, with particular attention given to their energy resolution and noise performance, which limits their active area considerably. (19 refs).

  6. The Vacuum Silicon Photomultiplier Tube (VSiPMT): A new version of a hybrid photon detector

    Energy Technology Data Exchange (ETDEWEB)

    Russo, Stefano, E-mail: srusso@na.infn.i [Universita di Napoli ' Federico II' , Dipartimento di Scienze fisiche, via Cintia 80126 Napoli (Italy); Barbarino, Giancarlo [Universita di Napoli ' Federico II' , Dipartimento di Scienze fisiche, via Cintia 80126 Napoli (Italy); Asmundis, Riccardo de; De Rosa, Gianfranca [Istituto Nazionale di fisica Nucleare, sezione di Napoli, Complesso di Monte S. Angelo Ed. 6, via Cintia 80126 Napoli (Italy)

    2010-11-01

    The future astroparticle experiments will study both energetic phenomena and extremely rare events from astrophysical sources. Since most of these families of experiments are carried out by using scintillation phenomena, Cherenkov or fluorescence radiation, the development of photosensitive detectors seems to be the right way to increase the experimental sensitivity. Therefore we propose an innovative design for a modern, high gain, silicon-based Vacuum Silicon Photomultiplier Tube (VSiPMT), which combines three fully established and well-understood technologies: the manufacture of hemispherical vacuum tubes with the possibility of very large active areas, the photocathode glass deposition and the novel Geiger-mode avalanche silicon photodiode (G-APD) for which a mass production is today available. This new design, based on G-APD as the electron multiplier, allows overcoming the limits of a classical PMT dynode chain.

  7. Photomultiplier Tubes at Cryogenic Temperatures

    Science.gov (United States)

    Saunders, Nathan

    2016-09-01

    Liquid noble gas scintillators are widely used in experiments searching for physics beyond the Standard Model. Photomultiplier Tubes (PMTs) working at cryogenic temperatures have been developed as the primary light readout device in those experiments. Three PMTs from Hamamatsu Photonics K.K. (R6041, R11065, and R8520) have been systematically characterized at liquid nitrogen temperature. The high voltage dividing circuits for two of the PMTs were custom-built to make sure there is similar performance at both room and liquid nitrogen temperatures. Their dark count rates at both temperatures were measured. Also measured were their single photoelectron responses at both temperatures using 300, 340, 370, and 420 nm LEDs. The intention is to couple these PMTs directly with inorganic scintillators at liquid nitrogen temperature to achieve high light yeilds for rare-event searches.

  8. Photon counting performance measurements of transfer electron InGaAsP photocathode hybrid photomultiplier tubes at 1064 nm wavelength

    Science.gov (United States)

    Sun, Xiaoli; Krainak, Michael A.; Hasselbrack, William B.; La Rue, Ross A.

    2007-05-01

    We report the test results of a hybrid photomultiplier tube (HPMT) with a transfer electron (TE) InGaAsP photocathode and GaAs Schottky avalanche photodiode (APD) anode. Unlike Geiger mode InGaAsP APDs, these HPMTs (also known as intensified photodiode (IPD), vacuum APD, or hybrid photodetector) operate in linear mode without the need for quenching and gating. Their greatest advantages are wide dynamic range, high speed, large photosensitive area, and potential for photon counting and analog detection dual mode operation. The photon detection efficiency we measured was 25% at 1064 nm wavelength with a dark count rate of 60,000/s at -22 degrees Celsius. The output pulse width in response to a single photon detection is about 0.9 ns. The maximum count rate was 90 Mcts/s and was limited solely by the speed of the discriminator used in the measurement (10 ns dead time). The spectral response of these devices extended from 900 to 1300 nm. We also measured the HPMT response to 60 ps laser pulses. The average output pulse amplitude increased monotonically with the input pulse energy, which suggested that we can resolve photon number in an incident pulse. The jitter of the HPMT output was found to be about 0.5 ns standard deviation and depended on bias voltage applied to the TE photocathode. To our knowledge, these HPMTs are the most sensitive non gating photon detectors at 1064 nm wavelength, and they will have many applications in laser altimeters, atmospheric lidars, and free space laser communication systems.

  9. Floating point processor for photomultiplier tube signals

    Energy Technology Data Exchange (ETDEWEB)

    Baron, P.; Joudon, A.; Lugiez, F.; Rouger, M. [C.E.A. Saclay, Gif sur Yvette (France)

    1995-08-01

    A chip was provided to read out the channels of the Shower Maximum Detector (SMD) in the electromagnetic calorimeter (EMC) of the S.D.C. experiment (solenoidal Detector Collaboration) at the Superconducting Super Collider project and shape of the electromagnetic shower with better precision than can be done by the EMC alone. A fast digital readout system has been designed for synchronous processing of the current signals delivered by a 64-channel multichannel photomultiplier tube (MCPMT) associated with fast scintillators. This mixed analog digital full custom chip uses a 1.2{micro}m A.M.S. CMOS process.

  10. Improving the performance of photomultiplier tubes

    Energy Technology Data Exchange (ETDEWEB)

    Harmer, S W [Department of Engineering and Technology, Manchester Metropolitan University, Manchester M1 5GD (United Kingdom); Townsend, P D, E-mail: pdtownsend@googlemail.co [Science and Technology, University of Sussex, Brighton BN1 9QH (United Kingdom)

    2010-10-20

    Photomultipliers are ubiquitous detectors of low level light signals, but their performance is limited by the complexity of photocathode technology. Two contributory problems are that light is lost both by surface reflection and by transmission through the photocathode layer. Knowledge of the dielectric constants has allowed predictive modelling of the reflectivity and absorption of the light as a function of angle of incidence, cathode thickness and polarization. The predictions have stimulated designs of extremely simple and very low cost retrofit approaches to improve the overall effectiveness of photomultipliers. One simple design presented here exploits signal that is normally lost by the surface reflection. A simple external conical torch reflector is clipped over the photomultiplier end face. The reflector raised the efficiency of an S20 multialkali photocathode by between 20% and 10% across the blue to red spectral range. An alternative semi-cylindrical glass coupler has improved the absorption efficiency by allowing the input signal to arrive at 60{sup 0} incidence to the photocathode surface, rather than normal incidence as in the standard head-on geometry. Enhancements are from 30% to 500% across the spectral range. The greater gains are at long wavelengths, and so are particularly valuable as this is the region of lowest quantum efficiency. The latter high-incidence angle approach, when applied to a low-efficiency C grade tube, has raised the performance to greater than the best of the A grade tubes, as used in the normal head-on operation. Both methods are equally applicable to other cathode compositions.

  11. Comparative studies of silicon photomultipliers and traditional vacuum photomultiplier tubes

    Institute of Scientific and Technical Information of China (English)

    石峰; 俞伯祥; 方建; 谢宇广; 安正华; 王志刚; 高旻; 李新乔; 徐岩冰; 王平; 孙希磊; 吕军光; 章爱武; 薛镇; 刘宏邦; 王晓东; 赵小芸; 郑阳恒; 孟祥承; 王辉; 卢红; 王焕玉; 马宇蒨; 胡涛; 周莉; 蔡啸; 孙丽君

    2011-01-01

    Silicon photomultipliers (SiPMs) are a new generation of semiconductor-based photon counting devices with the merits of low weight, low power consumption and low voltage operation, promising to meet the needs of space particle physics experiments. In this

  12. Underwater implosions of large format photo-multiplier tubes

    Energy Technology Data Exchange (ETDEWEB)

    Diwan, Milind; Dolph, Jeffrey [Brookhaven National Laboratory, P.O. Box 5000, Bldg 510E, Upton, NY 11973 (United States); Ling, Jiajie, E-mail: jjling@bnl.gov [Brookhaven National Laboratory, P.O. Box 5000, Bldg 510E, Upton, NY 11973 (United States); Russo, Thomas; Sharma, Rahul; Sexton, Kenneth; Simos, Nikolaos; Stewart, James; Tanaka, Hidekazu [Brookhaven National Laboratory, P.O. Box 5000, Bldg 510E, Upton, NY 11973 (United States); Arnold, Douglas; Tabor, Philip; Turner, Stephen [Naval Underwater Warfare Center, Newport, RI 02841 (United States)

    2012-04-01

    Large, deep, well shielded liquid detectors have become an important technology for the detection of neutrinos over a wide dynamic range from few MeV to TeV. The critical component of this technology is the large format semi-hemispherical photo-multiplier tube with diameters in the range of 25-50 cm. The survival of an assembled array of these photo-multiplier tubes under high hydrostatic pressure is the subject of this study. These are the results from an R and D program which is intended to understand the modes of failure when a photo-multiplier tube implodes under hydrostatic pressure. Our tests include detailed measurements of the shock wave which results from the implosion of a photo-multiplier tube and a comparison of the test data to modern hydrodynamic simulation codes. Using these results we can extrapolate to other tube geometries and make recommendation on deployment of the photo-multiplier tubes in deep water detectors with a focus on risk mitigation from a tube implosion shock wave causing a chain reaction loss of multiple tubes.

  13. Light Production in the Double Chooz Photomultiplier Tubes

    Energy Technology Data Exchange (ETDEWEB)

    Calvo, E.; Cerrada, M.; Crespo, J. I.; Gil-Botella, I.; Jimenez, S.; Lopez, M.; Novella, P.; Palomares, C.; Santorelli, R.; Verdugo, A.

    2012-09-13

    In this document we present a study of the phenomenon of light emission (called glowing) in the bases of the Hamamatsu R7081MOD-ASSY photomultiplier tubes (PMTs) used in the Double Chooz experiment. The tests have been carried out at the CIEMAT laboratories over a photomultiplier tube of the same model. We have studied the phenomenon making first a characterization of it, and then focusing on the dependence of the rate and the amount of emitted light versus voltage and temperature. In addition, we have looked for the possible existence of an ultraviolet component in the light which would be harmful for the experiment because it could be able to excite the scintillator liquid. Finally, we propose and test a method to reduce the light emission using a cover on the base of the photomultiplier tube.. (Author)

  14. Electron transit time measurements of 5-in photomultiplier tubes

    Science.gov (United States)

    Richards, T.; Peatross, J.; Ware, M.; Rees, L.

    2016-08-01

    We investigated the uniformity of electron transit times for two 5-in photomultiplier tubes: the Hamamatsu R1250 and the Adit B133D01S. We focused a highly attenuated short-pulse laser on the tubes while they were mounted on a programmable stage. The stage translated the tubes relative to the incident beam so that measurements could be made with light focused at points along a grid covering the entire photocathodes. A portion of the incident light was split from the incident beam and measured and recorded by a fast photodiode. Electron transit times were measured by computing the time delay between the recorded photodiode signal and photomultiplier signal using software constant-fraction discrimination. The Hamamatsu tube exhibited a uniform timing response that varied by no more than 1.7 ns. The Adit tube was much less uniform, with transit times that varied by as much as 57 ns. The Adit response also exhibited a spatially varying double-peak structure in its response. The technique described in this paper could be usefully employed by photomultiplier tube manufacturers to characterize the performance of their products.

  15. A new TDCR-LS counter using Channel photomultiplier tubes.

    Science.gov (United States)

    Ivan, C; Cassette, P; Sahagia, Maria

    2008-01-01

    A new Triple to Double Coincidence Ratio (TDCR) liquid scintillation (LS) counter using recently available photodetectors, the Channel photomultiplier (CPM) tubes, was constructed and tested in the framework of a scientific cooperation between IFIN-HH and LNHB. The prototype LS counter uses 3CPM tubes arranged symmetrically in an optical chamber around a standard LS vial. The behavior of the prototype was first evaluated with a light emitting diode (LED) light pulser. The counter was then compared against a TDCR counter using conventional photomultiplier tubes, by measuring (55)Fe, (3)H, (63)Ni and (90)Sr/(90)Y LS sources prepared in commercial liquid scintillation cocktails. Although the observed detection efficiency was significantly lower than the one achieved with the traditional counter, we found a remarkable agreement on the activity determination using the two counters. Details on the prototype and the measurement results obtained are discussed in this paper.

  16. Low Power Photomultiplier Tube Circuit And Method Thereor

    Science.gov (United States)

    Bochenski, Edwin B.; Skinner, Jack L.; Dentinger, Paul M.; Lindblom, Scott C.

    2006-04-18

    An electrical circuit for a photomultiplier tube (PMT) is disclosed that reduces power consumption to a point where the PMT may be powered for extended periods with a battery. More specifically, the invention concerns a PMT circuit comprising a low leakage switch and a high voltage capacitor positioned between a resistive divider and each of the PMT dynodes, and a low power control scheme for recharging the capacitors.

  17. Demonstration of photomultiplier tube operation at 29 K

    CERN Document Server

    Nikkel, J A; McKinsey, D N; Nikkel, James A.; Kinsey, Daniel N. Mc

    2007-01-01

    We describe measurements of gain, dark current, and quantum efficiency obtained while cooling a Hamamatsu R5912-02-MOD photomultiplier tube from room temperature to 29 K. We found that the PMT operated normally down to 29 K, with a reduced gain and quantum efficiency at the lowest temperatures. Furthermore, we found that the dark count rate increased as the temperature decreased. We conclude that these PMTs appear to be adequate for the requirements of the CLEAN experiment.

  18. New uses of position-sensitive photomultiplier tubes

    Science.gov (United States)

    Gordon, Jeffrey S.; Redus, Robert H.; Nagarkar, Vivek V.; Squillante, Michael R.

    1992-12-01

    Recent advances in photomultiplier tube technology have led to the availability of position sensitive photomultiplier tubes (PSPMTs). These tubes make it possible to build a new generation of imaging instruments for gamma rays and other types of ionizing radiation. We have investigated the use of these tubes for the construction of several prototype instruments. The first application investigated measures the quantity and distribution of radioactive compounds on filter papers used in microbiology research. The intent of this instrument is to replace film autoradiography with an electronic imaging system which can analyze samples 75 to 110 times faster than film. The second application involved the development of an intraoperative imaging probe to help surgeons identify cancerous tissue and ensure its complete removal. This instrument will replace a non-imaging probe now in use at many hospitals. A third prototype instrument under evaluation is an imaging nuclear survey system which obtains both a video and gamma ray image for the purpose of locating and quantifying radioactive materials. This system would be used at nuclear power plants and radioactive materials preparation facilities. A modification of this system could be built into robots used for inspecting and repairing power plants.

  19. Laboratory Investigations of Bidirectional Reflectance using the Photomultiplier Tube

    Science.gov (United States)

    Vides, C.; Nelson, R. M.; Boryta, M. D.; Manatt, K. S.

    2016-12-01

    The precise measurement of the intensity of a light source is fundamental data to observational sciences, such as spacecraft imaging and atomic particle detection. Photomultiplier tubes (PMT) have played an integral role in many diverse areas such as spacecraft remote sensing by indicating the physical properties of regolith on a planetary surface and particulate matter in an atmosphere. PMTs are essential in neutrino observatories by detecting Cherenkov radiation, the photons emitted when a neutrino interacts with a dielectric medium at highly relativistic velocities. The PMT utilizes the core principle of Albert Einstein's photoelectric effect, with the aid of secondary emission to multiply the electrons emitted from a primary photon. Traditionally, PMTs are used to measure the intensity of photons reflected from a surface. We designed a photometer such that we could measure the photoelectron current from two Hamamatsu R928 photomultiplier tubes, as amplified by Keithly 610 electrometers. The results provide insight into the behavior of photoelectrons, how temperature affects PMT output current, and the amplification electronics that form a basis for remote sensing measurements. We performed photometry with a maximum error of 1% by measuring the intensity of a coherent light source. The calibration procedure involved incrementing and decrementing the high voltage in steps of 50V on a high voltage power supply to locate the linear range within the Gaussian curve of light intensity as a function of high voltage to maximize the signal to noise. We have measured how the signal to noise ratio changes when transmittance was reduced and compared the performance of the PMTs. We measured the intensity as a function of polarization angle. We then measured the response change of the PMT as the reflectance of the incident surface changed. The data was reduced and analyzed using MATLAB. We corrected aliasing and fit the mathematical function of the photoelectron current in

  20. Multianode Photomultiplier Tubes for the LHCb RICH Photodetectors

    CERN Document Server

    Chamonal, R; Muheim, F

    2005-01-01

    The LHCB experiment is being built at the Large Hadron Collider facility at CERN in Geneva, Switzerland. The aim of the experiment is the precise measurement of CP violation parameters in the B-meson system. A critical requirement of the detector is a good pion/kaon separation provided by two Ring Imaging CHerenkov (RICH) counters. This thesis presents studies on the feasibility of using Multianode PhotoMultiplier Tubes (MaPMTs) as photodetectors in the LHCb RICH. We will establish the performances of MaPMTs in magnetic fields and also investigate how to shield them. Finally we present a testbeam analysis of a cluster of MaPMTs equipped with lenses at the CERN PS beam. The purpose of this testbeam was to demonstrate the operation of MaPMTS in a RICH prototype using the LHCb readout electronics.

  1. Light pulses to photomultiplier tubes from extended scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Albergo, S. [Catania Univ. (Italy). Ist. di Fisica; Boemi, D. [CSFNeSM, I-95129 Catania (Italy); Caccia, Z. [Catania Univ. (Italy). Ist. di Fisica; Costa, S. [Catania Univ. (Italy). Ist. di Fisica; Insolia, A. [Catania Univ. (Italy). Ist. di Fisica; Panebianco, S. [Catania Univ. (Italy). Ist. di Fisica; Potenza, R. [Catania Univ. (Italy). Ist. di Fisica; Randazzo, N. [Catania Univ. (Italy). Ist. di Fisica; Reito, S. [Catania Univ. (Italy). Ist. di Fisica; Romanski, J. [The Svedberg Laboratory, University of Uppsala, S751-21 Uppsala (Sweden); Russo, G.V. [Catania Univ. (Italy). Ist. di Fisica; Tuve, C. [Catania Univ. (Italy). Ist. di Fisica

    1995-08-15

    Light pulses seen by photomultiplier tubes (PMTs) after propagation within long scintillator slats or rods, or large disc-shaped scintillators are investigated and compared with those from point-like scintillators. Results of experimental tests for the disc-shaped configuration, performed with the single photon counting technique, are presented and compared with numerical calculations. These calculations were performed describing the light pulse shape by means of a new, quite general analytical method based on the geometrical optics concepts of virtual light paths and images. The associated electric pulses produced by the PMTs coupled to the scintillators are then discussed with particular emphasis on their dependence on the distance between light source and photocathode. (orig.).

  2. Implosion chain reaction mitigation in underwater assemblies of photomultiplier tubes

    Energy Technology Data Exchange (ETDEWEB)

    Ling, Jiajie, E-mail: jjling@bnl.gov [Brookhaven National Laboratory, Upton, NY 11973 (United States); Bishai, Mary; Diwan, Milind; Dolph, Jeffrey; Kettell, Steve; Sexton, Kenneth; Sharma, Rahul; Simos, Nikolaos; Stewart, James [Brookhaven National Laboratory, Upton, NY 11973 (United States); Tanaka, Hidekazu [Brookhaven National Laboratory, Upton, NY 11973 (United States); Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, 456 Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Viren, Brett [Brookhaven National Laboratory, Upton, NY 11973 (United States); Arnold, Douglas; Tabor, Philip; Turner, Stephen [Naval Undersea Warfare Center, Newport, RI 02841 (United States); Benson, Terry; Wahl, Daniel; Wendt, Christopher [University of Wisconsin-Madison, WI 53706 (United States); Hahn, Alan; Kaducak, Marc; Mantsch, Paul [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); and others

    2013-11-21

    Since the accident with a cascade failure of photomultiplier tubes (PMTs) in the Super-Kamiokande experiment in 2001, the mechanical performance of large format semi-hemispherical PMTs has become a critical issue for large water Cherenkov detectors. The subject of this study is the survival of an assembled array of PMTs under significant hydrostatic pressure and subjected to shock waves caused by the failure of a single PMT. This paper details the results of the second stage of a R and D program focused on the design and testing of different PMT assemblies to mitigate the risk of a “chain-reaction” of PMT failures. The initial results show that our PMT assembly design can effectively reduce the magnitude of the shock wave. With the testing results in this paper and the hydrodynamic simulation calculation, we can further improve the design of PMT deployment to mitigate the risk of chain reactions caused by implosion induced shock waves.

  3. Waterproofed photomultiplier tube assemblies for the Daya Bay reactor neutrino experiment

    Energy Technology Data Exchange (ETDEWEB)

    Chow, Ken [Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Cummings, John [Department of Physics and Astronomy, Siena College, Loudonville, NY 12211 (United States); Edwards, Emily [Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Edwards, William [Physics Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Ely, Ry [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Hoff, Matthew [Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Lebanowski, Logan [Department of Physics, University of Houston, Houston, TX 77204-5005 (United States); Li, Bo; Li, Piyi [School of Physics, Shandong University, Jinan 250100 (China); Lin, Shih-Kai [Department of Physics, University of Houston, Houston, TX 77204-5005 (United States); Liu, Dawei [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Liu, Jinchang [Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Beijing 100049 (China); Luk, Kam-Biu, E-mail: k_luk@berkeley.edu [Department of Physics, University of California, Berkeley, CA 94720 (United States); Physics Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Miao, Jiayuan [School of Physics, Shandong University, Jinan 250100 (China); Napolitano, Jim [Department of Physics, Temple University, Philadelphia, PA 19122 (United States); Ochoa-Ricoux, Juan Pedro [Physics Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Peng, Jen-Chieh [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Qi, Ming [Department of Physics, Nanjing University, Nanjing 210000 (China); and others

    2015-09-11

    In the Daya Bay Reactor Neutrino Experiment 960 20-cm-diameter waterproof photomultiplier tubes are used to instrument three water pools as Cherenkov detectors for detecting cosmic-ray muons. Of these 960 photomultiplier tubes, 341 are recycled from the MACRO experiment. A systematic program was undertaken to refurbish them as waterproof assemblies. In the context of passing the water leakage check, a success rate better than 97% was achieved. Details of the design, fabrication, testing, operation, and performance of these waterproofed photomultiplier-tube assemblies are presented.

  4. Waterproofed Photomultiplier Tube Assemblies for the Daya Bay Reactor Neutrino Experiment

    CERN Document Server

    Chow, Ken; Edwards, Emily; Edwards, William; Ely, Ry; Hoff, Matthew; Lebanowski, Logan; Li, Bo; Li, Piyi; Lin, Shih-Kai; Liu, Dawei; Liu, Jinchang; Luk, Kam-Biu; Miao, Jiayuan; Napolitano, Jim; Ochoa-Ricoux, Juan Pedro; Peng, Jen-Chieh; Qi, Ming; Steiner, Herbert; Stoler, Paul; Stuart, Mary; Wang, Lingyu; Yang, Changgen; Zhong, Weili

    2015-01-01

    In the Daya Bay Reactor Neutrino Experiment 960 20-cm-diameter waterproof photomultiplier tubes are used to instrument three water pools as Cherenkov detectors for detecting cosmic-ray muons. Of these 960 photomultiplier tubes, 341 are recycled from the MACRO experiment. A systematic program was undertaken to refurbish them as waterproof assemblies. In the context of passing the water leakage check, a success rate better than 97% was achieved. Details of the design, fabrication, testing, operation, and performance of these waterproofed photomultiplier-tube assemblies are presented.

  5. The effect of secondary processes in a photomultiplier tube on the characteristics of the photodetector

    Science.gov (United States)

    Vygon, V. G.; Iaroshenko, I. F.

    1983-10-01

    Expressions are derived for the mean value of the anodic current and the signal-to-noise ratio at the output of a photomultiplier tube, taking into account the formation of afterpulses. These expressions are used for the numerical calculation of the threshold sensitivity of a photomultiplier tube and the characteristics of the receiving system of a lidar. It is shown that the main factor determining this sensitivity is exoelectron emission from the dynodes. For spray-deposited emitters, having a high exoemission yield, the exoemission from the dynodes leads to a 5-10-fold deterioration in the threshold of the photomultiplier tube.

  6. Testing of Photomultiplier Tubes in a Magnetic Field

    Science.gov (United States)

    Waldron, Zachary; A1 Collaboration

    2016-09-01

    The A1 collaboration at MAMI in Mainz, Germany has designed a neutron detector that can be used in experiments to measure the electric form factor of the neutron. They will measure elastic scattering from the neutron, using the polarized electron beam from MAMI at A1's experimental hall. The detector will be composed of two walls of staggered scintillator bars which will be read out by photomultiplier tubes (PMT), connected to both ends of each scintillator via light guides. The experiment requires a magnetic field with strength of 1 Tesla, 2m away from the first scintillator wall. The resulting fringe field is sufficient to disrupt the PMTs, despite the addition of Mu Metal shielding. The effects of the fringe field on these PMTs was tested to optimize the amplification of the PMTs. A Helmholtz Coil was designed to generate a controlled magnetic field with equivalent strength to the field that the PMTs will encounter. The PMTs were read out using a multi-channel analyzer, were tested at various angles relative to the magnetic field in order to determine the optimal orientation to minimize signal disruption. Tests were also performed to determine: the neutron detector response to cosmic radiation; and the best method for measuring a magnetic field's strength in two dimensions. National Science Foundation Grant No. IIA-1358175.

  7. Characterization of the ETEL D784UKFLB 11 inch Photomultiplier Tube

    CERN Document Server

    Barros, N; Kimmelman, B; Klein, J R; Moore, E; Nguyen, J; Stavreva, K; Svoboda, R

    2015-01-01

    Water Cherenkov and scintillator detectors are a critical tool for neutrino physics.Their large size, low threshold, and low operational cost make them excellent detectors for long baseline neutrino oscillations, proton decay, supernova and solar neutrinos, double beta decay, and ultra-high energy astrophysical neutrinos. Proposals for a new generation of large detectors rely on the availability of large format, fast, cost-effective photomultiplier tubes. The Electron Tubes Enterprises, Ltd (ETEL) D784KFLB 11 inch Photomultiplier Tube has been developed for large neutrino detectors. We have measured the timing characteristics, relative efficiency, and magnetic field sensitivity of the first fifteen prototypes.

  8. The application of (RCA 1P 28)-photomultiplier tubes to the detection of weak light intensities

    NARCIS (Netherlands)

    Boeschoten, F.; Milatz, J.M.W.; Smit, C.

    1954-01-01

    Two methods are discussed of measuring weak light intensities (varying but slowly with time) with the aid of a photomultiplier tube. 1°. the light-chopping method in combination with a phase- and frequency-sensitive measuring device (i.c. alternating current galvanometer 1) 2) 3) 4) 16). 2°. the c

  9. Recent measurements on the Hamamatsu 13 in., R8055, PhotoMultiplier Tubes

    Science.gov (United States)

    The NESTOR Collaboration; Tsagli, S.; Aggouras, G.; Anassontzis, E. G.; Ball, A. E.; Chinowsky, W.; Fahrun, E.; Grammatikakis, G.; Green, C.; Grieder, P.; Katrivanos, P.; Koske, P.; Ludvig, J.; Markopoulos, E.; Minkowsky, P.; Nygren, D.; Papageorgiou, K.; Przybylski, G.; Resvanis, L. K.; Siotis, I.; Sopher, J.; Staveris, T.; Tsagli, V.; Zhukov, V. A.

    2006-11-01

    The key component of NESTOR, the deep-sea Cherenkov neutrino telescope, built in the Mediterranean, NW of Greece, is the optical module. The NESTOR Optical Module employs a PhotoMultiplier Tube (PMT) in a transparent glass pressure housing. The Hamamatsu PMT R8055-01, 13 in. photomultiplier was selected for NESTOR to replace the old 15'' Hamamatsu PMTs (R2018-03). Extensive tests have been made on the sensitivity, uniformity, time resolution and noise rates of 162 R8055-01 13 in. PMTs

  10. Model independent approach to the single photoelectron calibration of photomultiplier tubes

    Energy Technology Data Exchange (ETDEWEB)

    Saldanha, R.; Grandi, L.; Guardincerri, Y.; Wester, T.

    2017-08-01

    The accurate calibration of photomultiplier tubes is critical in a wide variety of applications in which it is necessary to know the absolute number of detected photons or precisely determine the resolution of the signal. Conventional calibration methods rely on fitting the photomultiplier response to a low intensity light source with analytical approximations to the single photoelectron distribution, often leading to biased estimates due to the inability to accurately model the full distribution, especially at low charge values. In this paper we present a simple statistical method to extract the relevant single photoelectron calibration parameters without making any assumptions about the underlying single photoelectron distribution. We illustrate the use of this method through the calibration of a Hamamatsu R11410 photomultiplier tube and study the accuracy and precision of the method using Monte Carlo simulations. The method is found to have significantly reduced bias compared to conventional methods and works under a wide range of light intensities, making it suitable for simultaneously calibrating large arrays of photomultiplier tubes.

  11. Lowering the radioactivity of the photomultiplier tubes for the XENON1T dark matter experiment

    Energy Technology Data Exchange (ETDEWEB)

    Aprile, E.; Contreras, H.; Goetzke, L.W.; Fernandez, A.J.M.; Messina, M.; Plante, G.; Rizzo, A. [Columbia University, Physics Department, New York, NY (United States); Agostini, F. [INFN-Laboratori Nazionali del Gran Sasso (Italy); Gran Sasso Science Institute, L' Aquila (Italy); Bologna Univ., Department of Physics and Astrophysics, Bologna (Italy); INFN, Bologna (Italy); Alfonsi, M. [Nikhef and the University of Amsterdam, Amsterdam (Netherlands); Johannes Gutenberg-Universitaet Mainz, Institut fuer Physik and Exzellenzcluster PRISMA, Mainz (Germany); Arazi, L.; Budnik, R.; Duchovni, E.; Gross, E.; Itay, R.; Landsman, H.; Lellouch, D.; Levinson, L.; Priel, N.; Vitells, O. [Weizmann Institute of Science, Department of Particle Physics and Astrophysics, Rehovot (Israel); Arisaka, K.; Lyashenko, A.; Meng, Y.; Pantic, E.; Teymourian, A.; Wang, H. [University of California, Physics and Astronomy Department, Los Angeles, CA (United States); Arneodo, F.; Di Giovanni, A. [New York University Abu Dhabi, Abu Dhabi (United Arab Emirates); Auger, M.; Barrow, P.; Baudis, L.; Behrens, A.; Galloway, M.; Kessler, G.; Kish, A.; Mayani, D.; Pakarha, P.; Piastra, F. [University of Zurich, Physik-Institut, Zurich (Switzerland); Balan, C.; Cardoso, J.M.R.; Lopes, J.A.M.; Santos, J.M.F. dos [University of Coimbra, Department of Physics, Coimbra (Portugal); Bauermeister, B.; Fattori, S.; Geis, C.; Grignon, C.; Oberlack, U.; Schindler, S. [Johannes Gutenberg-Universitaet Mainz, Institut fuer Physik and Exzellenzcluster PRISMA, Mainz (Germany); Beltrame, P. [Weizmann Institute of Science, Department of Particle Physics and Astrophysics, Rehovot (Israel); University of Edinburgh, Edinburgh (United Kingdom); Brown, A.; Lang, R.F.; Macmullin, S.; Pienaar, J.; Reichard, S.; Reuter, C. [Purdue University, Department of Physics and Astronomy, West Lafayette, IN (United States); Brown, E.; Levy, C. [Rensselaer Polytechnic Institute, Department of Physics, Applied Physics and Astronomy, Troy, NY (United States); Wilhelms-Universitaet Muenster, Institut fuer Kernphysik, Muenster (Germany); Bruenner, S.; Hampel, W.; Kaether, F.; Lindemann, S.; Lindner, M.; Undagoitia, T.M.; Rauch, L.; Schreiner, J.; Simgen, H.; Weber, M. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Bruno, G. [INFN-Laboratori Nazionali del Gran Sasso and Gran Sasso Science Institute, L' Aquila (Italy); Wilhelms-Universitaet Muenster, Institut fuer Kernphysik, Muenster (Germany); Buetikofer, L.; Coderre, D.; Schumann, M. [University of Bern, Albert Einstein Center for Fundamental Physics, Bern (Switzerland); Colijn, A.P.; Decowski, M.P.; Tiseni, A.; Tunnell, C. [Nikhef and the University of Amsterdam, Amsterdam (Netherlands); Cussonneau, J.P.; Le Calloch, M.; Masbou, J.; Lavina, L.S.; Thers, D. [Universite de Nantes, Subatech, Ecole des Mines de Nantes, CNRS/In2p3, Nantes (France); Ferella, A.D.; Fulgione, W.; Laubenstein, M. [INFN-Laboratori Nazionali del Gran Sasso and Gran Sasso Science Institute, L' Aquila (Italy); Fieguth, A.; Murra, M.; Rosendahl, S.; Weinheimer, C. [Wilhelms-Universitaet Muenster, Institut fuer Kernphysik, Muenster (Germany); Garbini, M.; Massoli, F.V.; Sartorelli, G.; Selvi, M. [Bologna Univ., Department of Physics and Astrophysics, Bologna (Italy); INFN, Bologna (Italy); Miguez, B.; Molinario, A.; Trinchero, G. [INFN-Torino and Osservatorio Astrofisico di Torino, Turin (Italy); Naganoma, J.; Shagin, P.; Wall, R. [Rice University, Department of Physics and Astronomy, Houston, TX (United States); Orrigo, S.E.A. [University of Coimbra, Department of Physics, Coimbra (Portugal); IFIC, CSIC-Universidad de Valencia, Valencia (Spain); Persiani, R. [Universite de Nantes, Subatech, Ecole des Mines de Nantes, CNRS/In2p3, Nantes (FR); Bologna Univ., Department of Physics and Astrophysics, Bologna (IT); INFN, Bologna (IT); Collaboration: XENON Collaboration

    2015-11-15

    The low-background, VUV-sensitive 3-inch diameter photomultiplier tube R11410 has been developed by Hamamatsu for dark matter direct detection experiments using liquid xenon as the target material. We present the results from the joint effort between the XENON collaboration and the Hamamatsu company to produce a highly radio-pure photosensor (version R11410-21) for the XENON1T dark matter experiment. After introducing the photosensor and its components, we show the methods and results of the radioactive contamination measurements of the individual materials employed in the photomultiplier production. We then discuss the adopted strategies to reduce the radioactivity of the various PMT versions. Finally, we detail the results from screening 286 tubes with ultra-low background germanium detectors, as well as their implications for the expected electronic and nuclear recoil background of the XENON1T experiment. (orig.)

  12. Lowering the radioactivity of the photomultiplier tubes for the XENON1T dark matter experiment

    Energy Technology Data Exchange (ETDEWEB)

    Aprile, E. [Physics Department, Columbia University, New York, NY (United States); Agostini, F. [INFN-Laboratori Nazionali del Gran Sasso and Gran Sasso Science Institute, L’Aquila (Italy); Department of Physics and Astrophysics, University of Bologna and INFN-Bologna, Bologna (Italy); Alfonsi, M. [Nikhef and the University of Amsterdam, Science Park, Amsterdam (Netherlands); Institut für Physik & Exzellenzcluster PRISMA, Johannes Gutenberg-Universität Mainz, Mainz (Germany); Arazi, L. [Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot (Israel); Collaboration: XENON Collaboration; and others

    2015-11-23

    The low-background, VUV-sensitive 3-inch diameter photomultiplier tube R11410 has been developed by Hamamatsu for dark matter direct detection experiments using liquid xenon as the target material. We present the results from the joint effort between the XENON collaboration and the Hamamatsu company to produce a highly radio-pure photosensor (version R11410-21) for the XENON1T dark matter experiment. After introducing the photosensor and its components, we show the methods and results of the radioactive contamination measurements of the individual materials employed in the photomultiplier production. We then discuss the adopted strategies to reduce the radioactivity of the various PMT versions. Finally, we detail the results from screening 286 tubes with ultra-low background germanium detectors, as well as their implications for the expected electronic and nuclear recoil background of the XENON1T experiment.

  13. Photocathode-Uniformity Tests of the Hamamatsu R5912 Photomultiplier Tubes Used in the Milagro Experiment

    CERN Document Server

    Vasileiou, V; Smith, A J

    2007-01-01

    The Milagro experiment observes the extensive air showers produced by very high energy gamma-rays impacting the Earth's atmosphere. Milagro uses 898 Hamamatsu R5912 Photomultiplier Tubes. To complete our Monte Carlo simulations, we tested the photocathode uniformity of our PMTs. The main finding was that the PMT gain and detection efficiency are a function of the distance from the center of the photocathode. Both quantities become considerably smaller as the illumination position nears the edge of the photocathode.

  14. Characterization of photomultiplier tubes in a novel secondary ionization mode for Secondary Emission Ionization Calorimetry

    CERN Document Server

    Tiras, E; Ogul, H; Southwick, D; Bilki, B; Nachtman, J; Onel, Y

    2016-01-01

    Hamamatsu single anode R7761 and multi-anode R5900-00-M16 Photomultiplier Tubes have been characterized for use in Secondary Emission Ionization Calorimetry study, that is a novel techique to measure the electromagnetic shower particles in extreme radiation environment. There are different SE modes used in the tests, developed from conventional PMT mode. Here, the technical design of secondary emission modules and characterization measurements of both SE modes and the PMT mode are reported.

  15. Testing of photomultiplier tubes for use in the surface detector of the Pierre Auger observatory

    Energy Technology Data Exchange (ETDEWEB)

    Barnhill, D. [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095-1547 (United States)], E-mail: david.scott.barnhill@gmail.com; Suarez, F. [INFN, Universita degli Studi di Torino (Italy)], E-mail: fedesuarez@auger.org.ar; Arisaka, K. [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095-1547 (United States); Garcia, B. [UTN-FRM Mendoza (Argentina); Gongora, J.P. [UTN-FRSR San Rafael (Argentina); Lucero, A.; Navarro, I. [UTN-FRM Mendoza (Argentina); Ohnuki, T. [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095-1547 (United States); Risi, A. [UTN-FRSR San Rafael (Argentina); Tripathi, A. [Department of Physics and Astronomy, UCLA, Los Angeles, CA 90095-1547 (United States)

    2008-07-01

    In the array of water Cherenkov detectors of the Pierre Auger Observatory, 4800 large photomultiplier tubes (PMTs) will be used. Before being deployed, each PMT is evaluated to check that various parameters, such as the linearity, dark noise, and gain, fall within a specified range. The large scale test system, designed and constructed for this purpose, is capable of testing multiple large PMTs simultaneously. The test system and the results of the tests for the first 3964 PMTs are presented in this paper.

  16. Qualification Tests of the R11410-21 Photomultiplier Tubes for the XENON1T Detector

    CERN Document Server

    Barrow, P; Cichon, D; Danisch, M; Franco, D; Kaether, F; Kish, A; Lindner, M; Undagoitia, T Marrodan; Mayani, D; Rauch, L; Wei, Y; Wulf, J

    2016-01-01

    The Hamamatsu R11410-21 photomultiplier tube is the photodetector of choice for the XENON1T dual-phase time projection chamber. The device has been optimized for a very low intrinsic radioactivity, a high quantum efficiency and a high sensitivity to single photon detection. A total of 248 tubes are currently operated in XENON1T, selected out of 321 tested units. In this article the procedures implemented to evaluate the large number of tubes prior to their installation in XENON1T are described. The parameter distributions for all tested tubes are shown, with an emphasis on those selected for XENON1T, of which the impact on the detector performance is discussed. All photomultipliers have been tested in a nitrogen atmosphere at cryogenic temperatures, with a subset of the tubes being tested in gaseous and liquid xenon, simulating their operating conditions in the dark matter detector. The performance and evaluation of the tubes in the different environments is reported and the criteria for rejection of PMTs are...

  17. Parametric Model for the Response of a Photo-multiplier Tube

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar, M.; Alcaraz, J.; Berdugo, J.; Casaus, J.; Delgado, C.; Diaz, C.; Lanciotti, E.; Mana, C.; Marin, J.; Martinez, G.; Molla, M.; Palomares, C.; Rodriguez, J.; Sanchez, E.; Sevilla, A.; Torrento, A.

    2005-07-01

    When a photon impinges upon a photon-multiplier tube, an electron is emitted with certain probability and, after several amplification stages, an electron shower is collected at the anode. However, when the first electron is emitted from one of the amplification dynodes or the photon-multiplier is operated under untoward conditions (external magnetic fields...) smaller showers are collected. In this paper, we present a bi-parametric model which describers the response of a photo-multiplier tube over a wide range of circumstances. (Author)

  18. K/Th/U in photomultiplier tubes and improved low-level NaI detectors

    Science.gov (United States)

    Theodorsson, Pall

    2003-06-01

    The study presented here is the first step in a program aimed at reducing significantly the background count rate of NaI scintillation units. We have investigated: (1) the residual background of a large well type NaI detector, i.e., when shielded with 10 cm of lead and operated deep underground, (2) low concentrations of primordial radioactivity in glass used for photomultiplier tubes (PMTs) and (3) the activity in whole tubes. The residual background of the NaI units is dominated by gamma radiation from potassium, thorium and uranium in the PMT, which severely limits their sensitivity. Activity in tubes made of new high purity glass was close to the detection level. The prospects of a new generation of low-level NaI detectors with these tubes are discussed.

  19. Advanced data readout technique for Multianode Position Sensitive Photomultiplier Tube applicable in radiation imaging detectors

    Science.gov (United States)

    Popov, V.

    2011-01-01

    Most of the best performing PSPMT tubes from Hamamatsu and Burle are designed with a pad-matrix anode layout. However, for obtaining a high resolution, a small-sized anode photomultiplier tubes are preferable; these tubes may have 64, 256 or 1024 anodes per tube. If the tubes are used in array to get a larger area detector, the number of analog channels may range from hundreds to thousands. Multichannel analog readout requires special electronics ICs, ASICs etc., which are attached to multichannel DAQ system. As a result, the data file and data processing time will be increased. Therefore, this readout could not be performed in a small project. Usually, most of radiation imaging applications allow the use of analog data processing in front-end electronics, significantly reducing the number of the detector's output lines to data acquisition without reducing the image quality. The idea of pad-matrix decoupling circuit with gain correction was invented and intensively tested in JLab. Several versions of PSPMT readout electronics were produced and studied. All developments were done and optimized specifically for radiation imaging projects. They covered high resolution SPECT, high speed PET, fast neutron imaging, and single tube and multi tube array systems. This paper presents and discusses the summary of the observed results in readout electronics evaluation with different PSPMTs and radiation imaging systems, as well as the advantages and limitations of the developed approach to radiation imaging detectors readout.

  20. Absolute optical responsivity down to the photon counting level with a photomultiplier tube

    Science.gov (United States)

    Tanabe, M.; Niwa, K.; Kinoshita, K.

    2017-04-01

    A novel method is presented for evaluation of the absolute optical responsivity of a photomultiplier tube (PMT) at optical powers down to the photon counting level under visible light. This method is based on a combination of the calibrated responsivity and nonlinearity corrections using a silicon photodiode and a PMT. The evaluation results with the PMT enable accurate determination of the absolute optical responsivity over a wide power range of 10-11 W to 10-16 W under visible light. This method provides validation of both the photon counting efficiency of a PMT and of accurate optical measurement with attenuators at the photon counting level.

  1. Development of 2D-ACAR apparatus using position-sensitive photomultiplier tubes

    Energy Technology Data Exchange (ETDEWEB)

    Nagai, Yasuyoshi; Saito, Haruo; Iwata, Tetsuya; Nagashima, Yasuyuki; Hyodo, Toshio [Tokyo Univ. (Japan). Coll. of Arts and Sciences; Uchida, Hiroshi; Omura, Tomohide

    1997-03-01

    A new two-dimensional angular correlation of annihilation radiation apparatus is described. Position-sensitive photomultiplier tubes coupled with two-dimensional arrays of small BGO scintillator blocks make simple and compact position-sensitive {gamma}-ray detectors. With a sample-detector distance of 5m, an angular resolution of 1.1 mrad FWHM and a coincidence count rate of {approx}2.4 c.p.s. per mCi are obtained. Its performance is demonstrated by the result of a test measurement for KI crystal in which non-localized positronium exists at low temperatures. (author)

  2. Setup a photomultiplier tube test bench for use at LHAASO-KM2A

    CERN Document Server

    Wang, Xu; Tian, Ye; Li, Changyu; Sun, Yansheng; Feng, Cunfeng

    2015-01-01

    To fulfill the requirements of testing the photomultiplier tubes of the electromagnetic detector at the Large High Altitude Air Shower Observatory (LHAASO), a multi-functional PMT test bench with a two-dimensional scanning system is developed. With this 2D scanning system, 16 PMTs are scanned simultaneously to test their uniformity and cathode transit time difference, and we can also perform PMT tests of SPE spectrum, gain vs. high voltage, linear behavior and dark noise. The programmable hardware and intelligent software of the test bench make it convenient to use and provide reliable results. The test methods are described in detail and primary results are presented.

  3. Test of digital neutron–gamma discrimination with four different photomultiplier tubes for the NEutron Detector Array (NEDA)

    Energy Technology Data Exchange (ETDEWEB)

    Luo, X.L., E-mail: luo.xiaoliang@physics.uu.se [Department of Instrument Science and Technology, College of Mechatronics and Automation, National University of Defense Technology, Changsha (China); Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala (Sweden); Modamio, V. [INFN, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Padova (Italy); Nyberg, J. [Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala (Sweden); Valiente-Dobón, J.J. [INFN, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Padova (Italy); Nishada, Q. [Department of Physics and Astronomy, Uppsala University, SE-75120 Uppsala (Sweden); Angelis, G. de [INFN, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Padova (Italy); Agramunt, J. [IFIC-CSIC, University of Valencia, Valencia (Spain); Egea, F.J. [IFIC-CSIC, University of Valencia, Valencia (Spain); Faculty of Engineering and Natural Sciences, Istanbul Sabahattin Zaim University, Istanbul (Turkey); Erduran, M.N.; Ertürk, S. [Nigde Universitesi, Fen-Edebiyat Falkültesi, Fizik Bölümü, Nigde (Turkey); France, G. de [GANIL, CEA/DSAM and CNRS/IN2P3, Bd Henri Becquerel, BP 55027, F-14076 Caen Cedex 05 (France); Gadea, A. [IFIC-CSIC, University of Valencia, Valencia (Spain); González, V. [Department of Electronic Engineering, University of Valencia, E-46071 Valencia (Spain); Hüyük, T. [IFIC-CSIC, University of Valencia, Valencia (Spain); Jaworski, G. [Faculty of Physics, Warsaw University of Technology, ul. Koszykowa 75, 00-662 Warszawa (Poland); Heavy Ion Laboratory, University of Warsaw, ul. Pasteura 5A, 02-093 Warszawa (Poland); Moszyński, M. [Heavy Ion Laboratory, University of Warsaw, ul. Pasteura 5A, 02-093 Warszawa (Poland); National Centre for Nuclear Research, A. Soltana 7, PL 05-400 Otwock-Swierk (Poland); and others

    2014-12-11

    A comparative study of the neutron–γ discrimination performance of a liquid scintillator detector BC501A coupled to four different 5 in. photomultiplier tubes (ET9390kb, R11833-100, XP4512 and R4144) was carried out. Both the Charge Comparison method and the Integrated Rise-Time method were implemented digitally to discriminate between neutrons and γ rays emitted by a {sup 252}Cf source. In both methods, the neutron–γ discrimination capabilities of the four photomultiplier tubes were quantitatively compared by evaluating their figure-of-merit values at different energy regions between 50 keVee and 1000 keVee. Additionally, the results were further verified qualitatively using time-of-flight to distinguish γ rays and neutrons. The results consistently show that photomultiplier tubes R11833-100 and ET9390kb generally perform best regarding neutron–γ discrimination with only slight differences in figure-of-merit values. This superiority can be explained by their relatively higher photoelectron yield, which indicates that a scintillator detector coupled to a photomultiplier tube with higher photoelectron yield tends to result in better neutron–γ discrimination performance. The results of this work will provide reference for the choice of photomultiplier tubes for future neutron detector arrays like NEDA.

  4. Development of an optical lens based alpha-particle imaging system using position sensitive photomultiplier tube

    Science.gov (United States)

    Ando, Koki; Oka, Miki; Yamamoto, Seiichi

    2017-02-01

    We developed an optical lens based alpha-particle imaging system using position sensitive photomultiplier tube (PSPMT). The alpha-particle imaging system consists of an optical lens, an extension tube and a 1 in. square high quantum efficiency (HQE) type PSPMT. After a ZnS(Ag) is attached to subject, the scintillation image of ZnS(Ag) is focused on the photocathode of the PSPMT by the use of the optical lens. With this configuration we could image the alpha particle distribution with energy information without contacting to the subject. The spatial resolution and energy resolution were 0.8 mm FWHM and 50% FWHM at 5 mm from the optical lens, respectively. We could successfully image the alpha particle distribution in uranium ore. The developed alpha-particle imaging system will be a new tool for imaging alpha emitters with energy information without contacting the subject.

  5. LHCb: Characterisation and magnetic field properties of Multianode Photomultiplier tubes for the use in LHCb Upgrade RICH detectors

    CERN Multimedia

    Eisenhardt, S; Morris, A; Needham, M; Neill, J

    2013-01-01

    A key feature of the LHCb upgrade, scheduled for 2019, is to remove the first level trigger and its data reduction from 40MHz to 1MHz, which is implemented in the on-detector readout electronics. The consequence for the LHCb Ring Imaging Cherenkov (RICH) detectors is that the Hybrid Photon Detectors need to be replaced as the readout chip is embedded in the tubes. Baseline for replacement are Multianode Photomultiplier tubes (MaPMT) and new readout electronics. Here we report about characterisation studies of the model Hamamatsu R11265 in the effort to qualify them for use in the LHCb RICH upgrade. Comparisons to the known model R7600 are also made. Two types of readout electronics are used. Most measurements to characterise the properties of the MaPMTs are taken with a VME based reference readout, using a x100 linear amplification and the CAEN V792 12-bit charge integrating digitiser. This allows to derive the signal properties from fits to the single photon spectra. In addition a prototype readout using the...

  6. Software Tools for the Analysis of the Photocathode Response of Photomultiplier Vacuum Tubes

    CERN Document Server

    Fabbri, R

    2013-01-01

    The central institute of electronics (ZEA-2) in the Forschungszentrum Juelich (FZJ) has developed a system to scan the response of the photocathode of photomultiplier tubes (PMT). The PMT sits tight on a supporting structure, while a blue light emitting diode is moved along its surface by two stepper motors, spanning both the x and y coordinates. All the system is located in a light-tight box made by wood. A graphical software was developed in-situ to perform the scan operations under different configurations (e.g., the step size of the scan and the number of measurements per point). During each point measurement the current output generated in the vacuum photomultiplier is processed in sequence by a pre-amplifier (mainly to convert the current signal into a voltage signal), an amplifier, and by an ADC module (typically a CAEN N957). The information of the measurement is saved in files at the end of the scan. Recently, software based on the CERN ROOT and on the Qt libraries was developed to help the user anal...

  7. Hybrid endotracheal tubes

    Science.gov (United States)

    Sakezles, Christopher Thomas

    Intubation involves the placement of a tube into the tracheal lumen and is prescribed in any setting in which the airway must be stabilized or the patient anesthetized. The purpose of the endotracheal tube in these procedures is to maintain a viable airway, facilitate mechanical ventilation, allow the administration of anesthetics, and prevent the reflux of vomitus into the lungs. In order to satisfy these requirements a nearly airtight seal must be maintained between the tube and the tracheal lining. Most conventional endotracheal tubes provide this seal by employing a cuff that is inflated once the tube is in place. However, the design of this cuff and properties of the material are a source of irritation and injury to the tracheal tissues. In fact, the complication rate for endotracheal intubation is reported to be between 10 and 60%, with manifestations ranging from severe sore throat to erosion through the tracheal wall. These complications are caused by a combination of the materials employed and the forces exerted by the cuff on the tracheal tissues. In particular, the abrasive action of the cuff shears cells from the lining, epithelium adhering to the cuff is removed during extubation, and normal forces exerted on the basement tissues disrupt the blood supply and cause pressure necrosis. The complications associated with tracheal intubation may be reduced or eliminated by employing airway devices constructed from hydrogel materials. Hydrogels are a class of crosslinked polymers which swell in the presence of moisture, and may contain more than 95% water by weight. For the current study, several prototype airway devices were constructed from hydrogel materials including poly(vinyl alcohol), poly(hydroxyethyl methacrylate), and poly(vinyl pyrrolidone). The raw hydrogel materials from this group were subjected to tensile, swelling, and biocompatibility testing, while the finished devices were subjected to extensive mechanical simulation and animal trials

  8. Monte Carlo calculations of the optical coupling between bismuth germanate crystals and photomultiplier tubes

    Energy Technology Data Exchange (ETDEWEB)

    Derenzo, S.E.; Riles, J.K.

    1981-10-01

    The high density and atomic number of bismuth germanate (Bi/sub 4/Ge/sub 3/O/sub 12/ or BGO) make it a very useful detector for positron emission tomography. Modern tomograph designs use large numbers of small, closely-packed crystals for high spatial resolution and high sensitivity. However, the low light output, the high refractive index (n=2.15), and the need for accurate timing make it important to optimize the transfer of light to the photomultiplier tube (PMT). We describe the results of a Monte Carlo computer program developed to study the effect of crystal shape, reflector type, and the refractive index of the PMT window on coupling efficiency. The program simulates total internal, external, and Fresnel reflection as well as internal absorption and scattering by bubbles.

  9. An Enhanced Measurement Of The Angular Response Of Photomultiplier Tubes At The Sudbury Neutrino Observatory

    CERN Document Server

    Simard, O

    2005-01-01

    The angular response of the photomultiplier tubes (PMTs) of the Sudbury Neutrino Observatory (SNO) is measured for an extended detector volume. Analytic and Monte Carlo studies of the reflections on the acrylic vessel made possible a full analysis of the optical data taken in a fiducial volume of 550 cm in radius, a 25% increase compared to previous analysis methods. The heavy and light water total extinctions found in that extended volume are consistent with previous measurements. The PMT angular response is also consistent, but extends in the range of incident angle [40°, 45°]. An approximation of the error due to this new optics on the energy scale uncertainty leads to a reduction of 1.25% on that uncertainty.

  10. Characterization of photomultiplier tubes in a novel operation mode for Secondary Emission Ionization Calorimetry

    Science.gov (United States)

    Tiras, E.; Dilsiz, K.; Ogul, H.; Southwick, D.; Bilki, B.; Wetzel, J.; Nachtman, J.; Onel, Y.; Winn, D.

    2016-10-01

    Hamamatsu single anode R7761 and multi-anode R5900-00-M16 Photomultiplier Tubes have been characterized for use in a Secondary Emission (SE) Ionization Calorimetry study. SE Ionization Calorimetry is a novel technique to measure electromagnetic shower particles in extreme radiation environments. The different operation modes used in these tests were developed by modifying the conventional PMT bias circuit. These modifications were simple changes to the arrangement of the voltage dividers of the baseboard circuits. The PMTs with modified bases, referred to as operating in SE mode, are used as an SE detector module in an SE calorimeter prototype, and placed between absorber materials (Fe, Cu, Pb, W, etc.). Here, the technical design of different operation modes, as well as the characterization measurements of both SE modes and the conventional PMT mode are reported.

  11. A useful method to monitor outputs from a pulsed light source and its application to rate effect studies in a photomultiplier tube

    CERN Document Server

    Takeuchi, Y; Kurashige, H; Matono, Y; Murakami, K; Nomura, T; Sakamoto, H; Sasao, N; Suehiro, M; Fukushima, Y; Ikegami, Y; Nakamura, T T; Taniguchi, T; Asai, M

    1999-01-01

    In order to study short-term gain stability in a photomultiplier tube at high counting rate, we constructed an LED pulsed light source and its output monitoring system. For the monitoring system, we employed a photon counting method using a photomultiplier as a monitor photon detector. It is found that the method offers a simple way to monitor outputs from a pulsed light source and that, together with an LED light source, it provides a useful method to investigate photomultiplier's rate effects.

  12. Replacement of a photomultiplier tube in a 2-inch thallium-doped sodium iodide gamma spectrometer with silicon photomultipliers and a light guide

    Directory of Open Access Journals (Sweden)

    Chankyu Kim

    2015-06-01

    Full Text Available The thallium-doped sodium iodide [NaI(Tl] scintillation detector is preferred as a gamma spectrometer in many fields because of its general advantages. A silicon photomultiplier (SiPM has recently been developed and its application area has been expanded as an alternative to photomultiplier tubes (PMTs. It has merits such as a low operating voltage, compact size, cheap production cost, and magnetic resonance compatibility. In this study, an array of SiPMs is used to develop an NaI(Tl gamma spectrometer. To maintain detection efficiency, a commercial NaI(Tl 2′ × 2′ scintillator is used, and a light guide is used for the transport and collection of generated photons from the scintillator to the SiPMs without loss. The test light guides were fabricated with polymethyl methacrylate and reflective materials. The gamma spectrometer systems were set up and included light guides. Through a series of measurements, the characteristics of the light guides and the proposed gamma spectrometer were evaluated. Simulation of the light collection was accomplished using the DETECT 97 code (A. Levin, E. Hoskinson, and C. Moison, University of Michigan, USA to analyze the measurement results. The system, which included SiPMs and the light guide, achieved 14.11% full width at half maximum energy resolution at 662 keV.

  13. Progress in characterization of the Photomultiplier Tubes for XENON1T Dark Matter Experiment

    CERN Document Server

    Lyashenko, Alexey

    2015-01-01

    We report on the progress in characterization of the Hamamatsu model R11410-21 Photomultiplier tubes (PMTs) for XENON1T dark matter experiment. The absolute quantum efficiency (QE) of the PMT was measured at low temperatures down to -110 $^0$C (a typical the PMT operation temperature in liquid xenon detectors) in a spectral range from 154.5 nm to 400 nm. At -110 $^0$C the absolute QE increased by 10-15\\% at 175 nm compared to that measured at room temperature. A new low power consumption, low radioactivity voltage divider for the PMTs is being developed. The measurement results showed that the PMT with the current version of the divider demonstrated a linear response (within 5\\%) down to 5$\\cdot$10$^4$ photoelectrons at a rate of 200 Hz. The radioactive contamination induced by the PMT and the PMT voltage divider materials satisfies the requirements for XENON1T detector not to exceed a total radioactive contamination in the detector of 0.5 evts/year/1tonn. Most of the PMTs received from the manufacturer showe...

  14. Measurement of the ratio h/e with a photomultiplier tube and a set of LEDs

    CERN Document Server

    Loparco, F; Rainò, S; Spinelli, P

    2016-01-01

    We propose a laboratory experience aimed at undergraduate physics students to understand the main features of the photoelectric effect and to perform a measurement of the ratio h/e, where h is the Planck's constant and e is the electron charge. The experience is based on the method developed by Millikan for his measurements on the photoelectric effect in the years from 1912 to 1915. The experimental setup consists of a photomultiplier tube (PMT) equipped with a voltage divider properly modified to set variable retarding potentials between the photocathode and the first dynode, and a set of LEDs emitting at different wavelengths. The photocathode is illuminated with the various LEDs and, for each wavelength of the incident light, the output anode current is measured as a function of the retarding potential applied between the cathode and the first dynode. From each measurement, a value of the stopping potential for the anode current is derived. Finally, the stopping potentials are plotted as a function of the ...

  15. Photomultiplier tube calibration based on Na lidar observation and its effect on heat flux bias.

    Science.gov (United States)

    Liu, Alan Z; Guo, Yafang

    2016-11-20

    Na lidar can measure vertical wind and temperature at high temporal and vertical resolutions, enough to resolve gravity wave perturbations. Heat flux due to dissipating gravity waves is an important quantity that can be derived from such perturbations. When lidar signals are high, a photomultiplier tube (PMT) used to count incoming photons may suffer from the saturation effect, and its output count is not linearly related to incoming photon counts. Corrections to this effect can be measured in a laboratory setting but may have large errors at high count rates. We show that the errors in the PMT correction can cause significant bias in the heat flux calculation due to the inherent correlation between wind and temperature errors. Using the measurements made by Na lidar at the Andes Lidar Observatory with Hamamatsu PMTs, we developed a calibration procedure to remove such PMT correction errors from laboratory measurements. By applying the revised PMT correction curve we demonstrated that the heat flux bias can be removed through this procedure.

  16. Analogue saturation limit of single and double 10 mm microchannel plate photomultiplier tubes

    Science.gov (United States)

    Milnes, J. S.; Conneely, T. M.; Horsfield, C. J.

    2016-11-01

    Photek are a well-established supplier of microchannel plate (MCP) photomultiplier tubes (PMTs) to the inertial confinement fusion community. The analogue signals produced at the major inertial confinement fusion facilities cover many orders of magnitude, therefore understanding the upper saturation limit of MCP-PMTs to large low rate signals takes on a high importance. Here we present a study of a single and a double MCP-PMT with 10 mm diameter active area. The saturation was studied for a range of optical pulse widths from 4 ns to 100 ns and at a range of electron gain values: 103 to 104 for the single and 104 to 106 for the double. We have shown that the saturation level of ˜1.2 nC depends only on the integrated charge of the pulse and is independent of pulse width and gain over this range, but that the level of charge available in deep saturation is proportional to the operating gain.

  17. Development of the Photomultiplier-Tube Readout System for the CTA Large Size Telescope

    CERN Document Server

    Kubo, H; Awane, Y; Bamba, A; Barcelo, M; Barrio, J A; Blanch, O; Boix, J; Delgado, C; Fink, D; Gascon, D; Gunji, S; Hagiwara, R; Hanabata, Y; Hatanaka, K; Hayashida, M; Ikeno, M; Kabuki, S; Katagiri, H; Kataoka, J; Konno, Y; Koyama, S; Kishimoto, T; Kushida, J; Martinez, G; Masuda, S; Miranda, J M; Mirzoyan, R; Mizuno, T; Nagayoshi, T; Nakajima, D; Nakamori, T; Ohoka, H; Okumura, A; Orito, R; Saito, T; Sanuy, A; Sasaki, H; Sawada, M; Schweizer, T; Sugawara, R; Sulanke, K -H; Tajima, H; Tanaka, M; Tanaka, S; Tejedor, L A; Terada, Y; Teshima, M; Tokanai, F; Tsuchiya, Y; Uchida, T; Ueno, H; Umehara, K; Yamamoto, T

    2013-01-01

    We have developed a prototype of the photomultiplier tube (PMT) readout system for the Cherenkov Telescope Array (CTA) Large Size Telescope (LST). Two thousand PMTs along with their readout systems are arranged on the focal plane of each telescope, with one readout system per 7-PMT cluster. The Cherenkov light pulses generated by the air showers are detected by the PMTs and amplified in a compact, low noise and wide dynamic range gain block. The output of this block is then digitized at a sampling rate of the order of GHz using the Domino Ring Sampler DRS4, an analog memory ASIC developed at Paul Scherrer Institute. The sampler has 1,024 capacitors per channel and four channels are cascaded for increased depth. After a trigger is generated in the system, the charges stored in the capacitors are digitized by an external slow sampling ADC and then transmitted via Gigabit Ethernet. An onboard FPGA controls the DRS4, trigger threshold, and Ethernet transfer. In addition, the control and monitoring of the Cockcrof...

  18. Non-descanned multifocal multiphoton microscopy with a multianode photomultiplier tube

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Jae Won; Yew, Elijah Y. S. [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA (United States); Kim, Daekeun [Department of Mechanical Engineering, Dankook University (Korea, Republic of); Subramanian, Jaichandar [Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA (United States); Nedivi, Elly [Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA (United States); Departments of Brain and Cognitive Sciences, and Biology, Massachusetts Institute of Technology, Cambridge, MA (United States); So, Peter T. C. [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA (United States); Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA (United States)

    2015-08-15

    Multifocal multiphoton microscopy (MMM) improves imaging speed over a point scanning approach by parallelizing the excitation process. Early versions of MMM relied on imaging detectors to record emission signals from multiple foci simultaneously. For many turbid biological specimens, the scattering of emission photons results in blurred images and degrades the signal-to-noise ratio (SNR). We have recently demonstrated that a multianode photomultiplier tube (MAPMT) placed in a descanned configuration can effectively collect scattered emission photons from each focus into their corresponding anodes significantly improving image SNR for highly scattering specimens. Unfortunately, a descanned MMM has a longer detection path resulting in substantial emission photon loss. Optical design constraints in a descanned geometry further results in significant optical aberrations especially for large field-of-view (FOV), high NA objectives. Here, we introduce a non-descanned MMM based on MAPMT that substantially overcomes most of these drawbacks. We show that we improve signal efficiency up to fourfold with limited image SNR degradation due to scattered emission photons. The excitation foci can also be spaced wider to cover the full FOV of the objective with minimal aberrations. The performance of this system is demonstrated by imaging interneuron morphological structures deep in the brains of living mice.

  19. Extension of photomultiplier tube dynamic range for the LHAASO-KM2A electromagnetic particle detectors

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Hongkui, E-mail: lvhk@ihep.ac.cn [Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Sheng, Xiangdong; He, Huihai; Liu, Jia [Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Zhang, Zhongquan [Shandong University, Jinan 250100 (China); Hou, Chao; Zhao, Jing [Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China)

    2015-05-01

    In the Large High Altitude Air Shower Observatory (LHAASO), the 1 km{sup 2} array (KM2A) requires linear measurement of optical intensity with a wide dynamic range. Over 5000 photomultiplier tubes (PMTs) are employed in this experiment and developed as “two outputs” device (anode and dynode) to meet the relevant requirements. In this study, the linearity of the anode and the eighth dynode (DY8), which is limited by space charge effects and mainly related to the relative dynode voltage ratios of the PMT divider, is examined. A voltage divider for the Hamamatsu R11102 PMT is designed and a dramatically enhanced linearity is demonstrated. Test results show that this design can cover a wide dynamic range from 20 to 2×10{sup 5} photoelectrons and achieve a peak anode current of 380 mA at a PMT gain of 10{sup 5}, which satisfies the requirements of KM2A electromagnetic particle detectors. The circuit design has been successfully simulated using the simulation software Multisim. The details of PMT performance tests and simulations are described.

  20. A novel ZVS high voltage power supply for micro-channel plate photomultiplier tubes

    Science.gov (United States)

    Pei, Chengquan; Tian, Jinshou; Liu, Zhen; Qin, Hong; Wu, Shengli

    2017-04-01

    A novel resonant high voltage power supply (HVPS) with zero voltage switching (ZVS), to reduce the voltage stress on switching devices and improve conversion efficiency, is proposed. The proposed HVPS includes a drive circuit, a transformer, several voltage multiplying circuits, and a regulator circuit. The HVPS contains several secondary windings that can be precisely regulated. The proposed HVPS performed better than the traditional resistor voltage divider, which requires replacing matching resistors resulting in resistor dispersibility in the Micro-Channel Plate (MCP). The equivalent circuit of the proposed HVPS was established and the operational principle analyzed. The entire switching element can achieve ZVS, which was validated by a simulation and experiments. The properties of this HVPS were tested including minimum power loss (240 mW), maximum power loss (1 W) and conversion efficiency (85%). The results of this research are that the proposed HVPS was suitable for driving the micro-channel plate photomultiplier tube (MCP-PMT). It was therefore adopted to test the MCP-PMT, which will be used in Daya Bay reactor neutrino experiment II in China.

  1. The Waveform Digitiser of the Double Chooz Experiment: Performance and Quantisation Effects on PhotoMultiplier Tube Signals

    CERN Document Server

    Abe, Y; Cabrera, A; Courty, B; Dawson, J V; Gonzalez, L F G; Hourlier, A; Ishitsuka, M; de Kerret, H; Kryn, D; Novella, P; Obolensky, M; Perasso, S; Remoto, A; Roncin, R

    2013-01-01

    We present the waveform digitiser used in the Double Chooz experiment. We describe the hardware and the custom-built firmware specifically developed for the experiment. The performance of the device is tested with regards to digitising low light level signals from photomultiplier tubes and measuring pulse charge. This highlights the role of quantisation effects and leads to some general recommendations on the design and use of waveform digitisers.

  2. Studies of relative gain and timing response of fine-mesh photomultiplier tubes in high magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Sulkosky, Vincent A. [Univ. of Virginia, Charlottesville, VA (United States); Allison-Russell, Lyndsey L. [Hampton Univ., Hampton, VA (United States); Barber, Corinne C. [Univ. of South Carolina, Columbia, SC (United States); Cao, Tongtong [Univ. of South Carolina, Columbia, SC (United States); Ilieva, Yordanka [Univ. of South Carolina, Columbia, SC (United States); Jin, Kai [Univ. of Virginia, Charlottesville, VA (United States); Kalicy, Grzegorz [Old Dominion Univ., Norfolk, VA (United States); Park, K. [Old Dominion Univ., Norfolk, VA (United States); Ton, N. [Univ. of Virginia, Charlottesville, VA (United States); Zheng, Xiaochao [Univ. of Virginia, Charlottesville, VA (United States)

    2016-05-01

    We investigated the use of Hamamatsu fine-mesh photomultiplier tube assemblies H6152-70 and H6614-70 with regards to their gain and timing resolution in magnetic fields up to 1.9 T. Our results show that the H6614-70 assembly can operate reliably in magnetic fields exceeding 1.5 T, while preserving a reasonable timing resolution even with a gain reduction of a factor of ~100. The reduction of the relative gain of the H6152-70 is similar to the H6614-70's near 1.5 T, but its timing resolution worsens considerably at this high field.

  3. Measurements of wavelength-dependent double photoelectron emission from single photons in VUV-sensitive photomultiplier tubes

    CERN Document Server

    Faham, C H; Currie, A; Dobi, A; Sorensen, P; Gaitskell, R J

    2015-01-01

    Measurements of double photoelectron emission (DPE) probabilities as a function of wavelength are reported for Hamamatsu R8778, R8520, and R11410 VUV-sensitive photomultiplier tubes (PMTs). In DPE, a single photon strikes the PMT photocathode and produces two photoelectrons instead of a single one. It was found that the fraction of detected photons that result in DPE emission is a function of the incident photon wavelength, and manifests itself below $\\sim$250 nm. For the xenon scintillation wavelength of 175 nm, a DPE probability of 18--24\\% was measured depending on the tube and measurement method. This wavelength-dependent single photon response has implications for the energy calibration and photon counting of current and future liquid xenon detectors such as LUX, LZ, XENON100/1T, Panda-X and XMASS.

  4. Characterization of the Hamamatsu H12700A-03 and R12699-03 multi-anode photomultiplier tubes

    CERN Document Server

    Calvi, Marta; Cassina, Lorenzo; Gotti, Claudio; Maino, Matteo; Matteuzzi, Clara; Pessina, Gianluigi

    2015-01-01

    The H12700 is a novel 64-channel 52 $\\times$ 52 mm$^2$ square Multi-Anode PhotoMultiplier Tube (MaPMT) produced by Hamamatsu. Its characteristics make this device suitable for high energy physics applications, such as in Ring Imaging Cherenkov (RICH) detectors. Hamamatsu provides the H12700 tube with an embedded socket connecting the anodes to the output pins and including an active voltage divider. A second device version, the R12699, is also available and differs from the former by the absence of the socket. This paper describes a complete characterization of both models, starting from the standard operating parameters (single photon spectra, average gain, anode uniformity and dark current value), investigating in detail the cross-talk effect among neighbouring pixels and considering the behaviour in critical environment conditions, such as in presence of a static magnetic field up to 100 Gauss, at different operating temperatures and after long exposure to intense light.

  5. Study of performance of small gamma camera consisting of crystal pixel array and position sensitive photomultiplier tube

    Institute of Scientific and Technical Information of China (English)

    ZHU Jie; LIU Shi-Tao; LEI Xiao-Wen; YAN Tian-Xin; XU Zi-Zong; WANG Zhao-Min

    2005-01-01

    The performance of gamma camera with NaI(T1) array coupled with position sensitive photomultiplier tube (PSPMT) R2486 has been studied. The pixel size of NaI(T1) crystal is 2mm×2mm and the overall dimension of the array is 48.2mm×48.2mm×5mm. There are 484 pixels in a 22×22 matrix. Because each pixel can produce a much focused light spot and restrict the spread of photons, position resolution of the gamma camera is mainly determined by pixel size. It is shown that crystal array pixel can reduce shrinkage effect and improve intrinsic position resolution greatly via restricting the spread of photons. Experimental results demonstrate that its position resolution and linearity are much improved comparing with the gamma camera using planar crystals coupled with PSPMT.

  6. Light yield of an undoped CsI crystal coupled directly to a photomultiplier tube at 77 Kelvin

    Science.gov (United States)

    Liu, Jing; Yamashita, Masaki; Soma, Arun Kumar

    2017-01-01

    A light yield of 20 . 4 +/- 0 . 8 photoelectrons/keV was achieved with an undoped CsI crystal coupled directly to a photomultiplier tube at 77 Kelvin. This is by far the largest in the world achieved with CsI crystals. An energy threshold that is several times lower than the current dark matter experiments utilizing CsI(Tl) crystals may be achievable using this technique. Together with novel CsI crystal purification methods, the technique may be used to improve the sensitivities of dark matter and coherent elastic neutrino-nucleus scattering experiments. Also measured were the scintillation light decay constants of the undoped CsI crystal at both room temperature and 77 Kelvin. The results are consistent with those in the literature. This work was supported by NSF PHY-1506036, USA and Grant-in-Aid (B) Project No. 26800122, MEXT, Japan.

  7. Light yield of an undoped CsI crystal coupled directly to a photomultiplier tube at 77 Kelvin

    CERN Document Server

    Liu, Jing; Soma, Arun Kumar

    2016-01-01

    A light yield of 20.4 $\\pm$ 0.8 photoelectrons/keV was achieved with an undoped CsI crystal coupled directly to a photomultiplier tube at 77 Kelvin. This is by far the largest yield in the world achieved with CsI crystals. An energy threshold that is several times lower than the current dark matter experiments utilizing CsI(Tl) crystals may be achievable using this technique. Together with novel CsI crystal purification methods, the technique may be used to improve the sensitivities of dark matter and coherent elastic neutrino-nucleus scattering experiments. Also measured were the scintillation light decay constants of the undoped CsI crystal at both room temperature and 77 Kelvin. The results are consistent with those in the literature.

  8. Comparison between large area photo-multiplier tubes at cryogenic temperature for neutrino and rare event physics experiments

    Energy Technology Data Exchange (ETDEWEB)

    Falcone, A., E-mail: andrea.falcone@pv.infn.it [University of Pavia – Via Bassi 6, 27100 Pavia (Italy); INFN Sezione di Pavia – Via Bassi 6, 27100 Pavia (Italy); Bertoni, R. [INFN Sezione di Milano Bicocca – Piazza della Scienza 3, 20126 Milano (Italy); Boffelli, F. [University of Pavia – Via Bassi 6, 27100 Pavia (Italy); INFN Sezione di Pavia – Via Bassi 6, 27100 Pavia (Italy); Bonesini, M. [INFN Sezione di Milano Bicocca – Piazza della Scienza 3, 20126 Milano (Italy); Cervi, T. [University of Pavia – Via Bassi 6, 27100 Pavia (Italy); Menegolli, A. [University of Pavia – Via Bassi 6, 27100 Pavia (Italy); INFN Sezione di Pavia – Via Bassi 6, 27100 Pavia (Italy); Montanari, C.; Prata, M.C.; Rappoldi, A.; Raselli, G.L.; Rossella, M. [INFN Sezione di Pavia – Via Bassi 6, 27100 Pavia (Italy); Spanu, M. [University of Pavia – Via Bassi 6, 27100 Pavia (Italy); Torti, M. [University of Pavia – Via Bassi 6, 27100 Pavia (Italy); INFN Sezione di Pavia – Via Bassi 6, 27100 Pavia (Italy); Zani, A. [INFN Sezione di Pavia – Via Bassi 6, 27100 Pavia (Italy)

    2015-07-01

    An evaluation of the behavior of three large cathode area photo-multiplier tubes, Hamamatsu R5912 Mod and R5912-02 Mod, and ETL 9357 KFLB, was carried out both at room and cryogenic temperature, using a 405 nm light source. The main electrical and optical features of the devices were studied; the obtained results were compared with the characteristics of the ETL 9357 FLA tubes, used in the ICARUS experiment. Tubes were also studied as a function of the Earth's magnetic field and an evaluation of the quantum efficiency was made in the vacuum ultraviolet light region. - Highlights: • We tested three 8-in. PMTs both at room and at cryogenic temperature. • The response as a function of the terrestrial magnetic field was tested. • The quantum efficiency for VUV light was measured. • Gain, linearity and dark count rate at 77 K and at 300 K were compared. • The PMTs were found able to work at cryogenic temperature.

  9. Comparative study of PP0275C hybrid photodetector and XP2020Q photomultiplier in scintillation detection

    Energy Technology Data Exchange (ETDEWEB)

    Moszynski, Marek [Soltan Institute for Nuclear Studies, PL 05-400 Swierk-Otwock (Poland); Klamra, Wlodzimierz [Royal Institute of Technology, AlbaNova, S-106 91 Stockholm (Sweden); Wolski, Dariusz [Soltan Institute for Nuclear Studies, PL 05-400 Swierk-Otwock (Poland); Czarnacki, Wieslaw [Soltan Institute for Nuclear Studies, PL 05-400 Swierk-Otwock (Poland); Kapusta, Maciej [Soltan Institute for Nuclear Studies, PL 05-400 Swierk-Otwock (Poland); Balcerzyk, Marcin [Soltan Institute for Nuclear Studies, PL 05-400 Swierk-Otwock (Poland)

    2006-05-15

    The properties of a hybrid photodetector (HPD), type PP0275C, produced by Delft Electronic Products B.V., for scintillation detection and spectrometry were studied and compared to a standard XP2020Q photomultiplier. The study was performed for several scintillators, such as NaI(Tl), CsI(Tl) and LSO(Ce) of different dimensions. The excellent capability of the HPD to resolve single photoelectron events was fully confirmed. However, the study of the HPD with the scintillators showed a dramatically reduced number of photoelectrons and a further deterioration of energy resolution, depending on the size (diameter or length) of the crystals. For a 10 mm diameter NaI(Tl) a number of 5000{+-}250 photoelectrons/MeV was measured, which corresponds to about 56% of that observed with the XP2020Q with comparable quantum efficiency. An energy resolution of 9.2% for 662 keV {gamma}-rays from a {sup 137}Cs source as measured with the HPD light readout indicated on a serious degradation, larger than that arising from the statistics of photoelectrons. In conclusion, the study showed that this HPD is optimized for single photon detection but its application to scintillation detection is very limited.

  10. Constructing Hybrid Baryons with Flux Tubes

    CERN Document Server

    Capstick, Simon; Capstick, Simon; Page, Philip R.

    1999-01-01

    Hybrid baryon states are described in quark potential models as having explicit excitation of the gluon degrees of freedom. Such states are described in a model motivated by the strong coupling limit of Hamiltonian lattice gauge theory, where three flux tubes meeting at a junction play the role of the glue. The adiabatic approximation for the quark motion is used, and the flux tubes and junction are modeled by beads which are attracted to each other and the quarks by a linear potential, and vibrate in various string modes. Quantum numbers and estimates of the energies of the lightest hybrid baryons are provided.

  11. Hybrid charge division multiplexing method for silicon photomultiplier based PET detectors

    Science.gov (United States)

    Park, Haewook; Ko, Guen Bae; Lee, Jae Sung

    2017-06-01

    Silicon photomultiplier (SiPM) is widely utilized in various positron emission tomography (PET) detectors and systems. However, the individual recording of SiPM output signals is still challenging owing to the high granularity of the SiPM; thus, charge division multiplexing is commonly used in PET detectors. Resistive charge division method is well established for reducing the number of output channels in conventional multi-channel photosensors, but it degrades the timing performance of SiPM-based PET detectors by yielding a large resistor-capacitor (RC) constant. Capacitive charge division method, on the other hand, yields a small RC constant and provides a faster timing response than the resistive method, but it suffers from an output signal undershoot. Therefore, in this study, we propose a hybrid charge division method which can be implemented by cascading the parallel combination of a resistor and a capacitor throughout the multiplexing network. In order to compare the performance of the proposed method with the conventional methods, a 16-channel Hamamatsu SiPM (S11064-050P) was coupled with a 4  ×  4 LGSO crystal block (3  ×  3  ×  20 mm3) and a 9  ×  9 LYSO crystal block (1.2  ×  1.2  ×  10 mm3). In addition, we tested a time-over-threshold (TOT) readout using the digitized position signals to further demonstrate the feasibility of the time-based readout of multiplexed signals based on the proposed method. The results indicated that the proposed method exhibited good energy and timing performance, thus inheriting only the advantages of conventional resistive and capacitive methods. Moreover, the proposed method showed excellent pulse shape uniformity that does not depend on the position of the interacted crystal. Accordingly, we can conclude that the hybrid charge division method is useful for effectively reducing the number of output channels of the SiPM array.

  12. A versatile test bench for photomultiplier tube characterization and its application in the DAMPE-PSD

    CERN Document Server

    Zhou, Yong; Yu, Yuhong; Zhang, Yongjie; Fang, Fang; Chen, Junling; Hu, Bitao

    2016-01-01

    A versatile test bench system, dedicated for massive PMT characterization, is developed at the Institute of Modern Physics, Chinese Academy of Sciences. It can perform many test contents with large capacity and high level of automation, and the migration from one testing configuration to another is lightweight and time-saving. This system has been used in the construction of the Plastic Scintillator Detector of DArk Matter Particle Explorer already, and a total of 570 Hamamatsu R4443 tubes have been tested successfully.

  13. Development of the photomultiplier tube readout system for the first Large-Sized Telescope of the Cherenkov Telescope Array

    CERN Document Server

    Masuda, Shu; Barrio, Juan Abel; Bigas, Oscar Blanch; Delgado, Carlos; Coromina, Lluís Freixas; Gunji, Shuichi; Hadasch, Daniela; Hatanaka, Kenichiro; Ikeno, Masahiro; Laguna, Jose Maria Illa; Inome, Yusuke; Ishio, Kazuma; Katagiri, Hideaki; Kubo, Hidetoshi; Martínez, Gustavo; Mazin, Daniel; Nakajima, Daisuke; Nakamori, Takeshi; Ohoka, Hideyuki; Paoletti, Riccardo; Ritt, Stefan; Rugliancich, Andrea; Saito, Takayuki; Sulanke, Karl-Heinz; Takeda, Junki; Tanaka, Manobu; Tanigawa, Shunsuke; Tejedor, Luis Ángel; Teshima, Masahiro; Tsuchiya, Yugo; Uchida, Tomohisa; Yamamoto, Tokonatsu

    2015-01-01

    The Cherenkov Telescope Array (CTA) is the next generation ground-based very high energy gamma-ray observatory. The Large-Sized Telescope (LST) of CTA targets 20 GeV -- 1 TeV gamma rays and has 1855 photomultiplier tubes (PMTs) installed in the focal plane camera. With the 23 m mirror dish, the night sky background (NSB) rate amounts to several hundreds MHz per pixel. In order to record clean images of gamma-ray showers with minimal NSB contamination, a fast sampling of the signal waveform is required so that the signal integration time can be as short as the Cherenkov light flash duration (a few ns). We have developed a readout board which samples waveforms of seven PMTs per board at a GHz rate. Since a GHz FADC has a high power consumption, leading to large heat dissipation, we adopted the analog memory ASIC "DRS4". The sampler has 1024 capacitors per channel and can sample the waveform at a GHz rate. Four channels of a chip are cascaded to obtain deeper sampling depth with 4096 capacitors. After a trigger ...

  14. Characterization of HZC XP1805 photomultiplier tube for LHAASO-WCDA with a high dynamic range base

    Science.gov (United States)

    Zhao, X.; Tang, Z.; Li, C.; Li, X.; Zha, W.; Chen, H.; Zhang, Y.; Shao, M.; Sun, Y.; Zhou, Y.

    2016-10-01

    The Water Cherenkov Detector Array (WCDA) for the Large High Altitude Air Shower Observatory (LHAASO) will employ 3000 large-sized hemisphere photomultiplier tubes (PMTs) to collect the Cherenkov light produced by shower particles crossing water. The PMTs require not only good single photoelectron (SPE) resolution and small transit time spread (TTS), but also good linearity up to 4000 photoelectrons. XP1805 PMT produced by Hainan Zhanchuang Photonics Technology Co., Ltd (HZC), China, with a production line imported from Photonis (France) is a good candidate for LHAASO-WCDA readout. In this paper, the design of a high dynamic range base for XP1805 is presented. The SPE responses and non-linearity of XP1805 with the high dynamic range base are measured. These results show that HZC XP1805 with the designed base is well qualified for LHAASO-WCDA, with peak-to-valley ratio greater than 2, TTS around 3 ns, dynamic range (non-linearity within 5%) over 1500 and 5300 photoelectrons for anode and the 6th dynode output, respectively, at PMT gain of 3 × 106 with the inciting light pulse width of 6.4 ns.

  15. Calibration of a photomultiplier array spectrometer

    Science.gov (United States)

    Bailey, Steven A.; Wright, C. Wayne; Piazza, Charles R.

    1989-01-01

    A systematic approach to the calibration of a photomultiplier array spectrometer is presented. Through this approach, incident light radiance derivation is made by recognizing and tracing gain characteristics for each photomultiplier tube.

  16. Demonstration and Comparison of Operation of Photomultiplier Tubes at Liquid Argon Temperature

    CERN Document Server

    Acciarri, R; Boffelli, F; Cambiaghi, M; Canci, N; Cavanna, F; Cocco, A G; Di Pompeo, F; Fiorillo, G; Galbiati, C; Grandi, L; Kryczynski, P; Meng, G; Montanari, C; Palamara, O; Pandola, L; Perfetto, F; Mortari, G B Piano; Pietropaolo, F; Raselli, G L; Rossella, M; Rubbia, C; Segreto, E; Szelc, A M; Triossi, A; Ventura, S; Vignoli, C; Zani, A

    2011-01-01

    Liquified noble gases are widely used as a target in direct Dark Matter searches. Signals from scintillation in the liquid, following energy deposition from the recoil nuclei scattered by Dark Matter particles (e.g. WIMPs), should be recorded down to very low energies by photosensors suitably designed to operate at cryogenic temperatures. Liquid Argon based detectors for Dark Matter searches currently implement photo multiplier tubes for signal read-out. In the last few years PMTs with photocathodes operating down to liquid Argon temperatures (87 K) have been specially developed with increasing Quantum Efficiency characteristics. The most recent of these, Hamamatsu Photonics Mod. R11065 with peak QE up to about 35%, has been extensively tested within the R&D program of the WArP Collaboration. During these testes the Hamamatsu PMTs showed superb performance and allowed obtaining a light yield around 7 phel/keVee in a Liquid Argon detector with a photocathodic coverage in the 12% range, sufficient for detec...

  17. Performance of new 8-inch photomultiplier tube used for the Tibet muon-detector array

    CERN Document Server

    Huang, Ying Zhangm Jing; Zhai, Liu-Ming; Chen, Xu; Hu, Xiao-Bin; Lin, Yu-Hui; Zhang, Xue-Yao; Feng, Cun-Feng; Jia, Huan-Yu; Zhou, Xun-Xiu; Dan-Zen, Luo-bu; Chen, Tian-Lu; Laba, Ci-Ren; Mao-Yuan,; Gao, Qi; Zha-xi, Ci-ren

    2016-01-01

    A new hybrid experiment has been constructed to measure the chemical composition of cosmic rays around the "knee" in the wide energy range by the Tibet AS$\\gamma$ collaboration at Tibet, China, since 2014. They consist of a high-energy air-shower-core array (YAC-II), a high-density air-shower array (Tibet-III) and a large underground water-Cherenkov muon-detector array (MD). In order to obtain the primary proton, helium and iron spectra and their "knee" positions in the energy range lower than $10^{16}$ eV, each of PMTs equipped to the MD cell is required to measure the number of photons capable of covering a wide dynamic range of 100 - $10^{6}$ photoelectrons (PEs) according to Monte Carlo simulations. In this paper, we firstly compare the characteristic features between R5912-PMT made by Japan Hamamatsu and CR365-PMT made by Beijing Hamamatsu. This is the first comparison between R5912-PMT and CR365-PMT. If there exists no serious difference, we will then add two 8-inch-in-diameter PMTs to meet our requirem...

  18. A novel compensation method for the anode gain non-uniformity of multi-anode photomultiplier tubes.

    Science.gov (United States)

    Lee, Chan Mi; Il Kwon, Sun; Ko, Guen Bae; Ito, Mikiko; Yoon, Hyun Suk; Lee, Dong Soo; Hong, Seong Jong; Lee, Jae Sung

    2012-01-07

    The position-sensitive multi-anode photomultiplier tube (MA-PMT) is widely used in high-resolution scintillation detectors. However, the anode gain nonuniformity of this device is a limiting factor that degrades the intrinsic performance of the detector module. The aim of this work was to develop a gain compensation method for the MA-PMT and evaluate the resulting enhancement in the performance of the detector. The method employs a circuit that is composed only of resistors and is placed between the MA-PMT and a resistive charge division network (RCN) used for position encoding. The goal of the circuit is to divide the output current from each anode, so the same current flows into the RCN regardless of the anode gain. The current division is controlled by the combination of a fixed-value series resistor with an output impedance that is much larger than the input impedance of the RCN, and a parallel resistor, which detours part of the current to ground. PSpice simulations of the compensation circuit and the RCN were performed to determine optimal values for the compensation resistors when used with Hamamatsu H8500 MAPMTs. The intrinsic characteristics of a detector module consisting of this MA-PMT and a lutetium-gadolinium-oxyorthosilicate (LGSO) crystal array were tested with and without the gain compensation method. In simulation, the average coefficient of variation and max/min ratio decreased from 15.7% to 2.7% and 2.0 to 1.2, respectively. In the flood map of the LGSO-H8500 detector, the uniformity of the photopeak position for individual crystals and the energy resolution were much improved. The feasibility of the method was shown by applying it to an octagonal prototype positron emission tomography scanner.

  19. Performance of new 8-inch photomultiplier tube used for the Tibet muon-detector array

    Science.gov (United States)

    Zhang, Y.; Huang, J.; Chen, D.; Zhai, L.-M.; Chen, X.; Hu, X.-B.; Lin, Y.-H.; Jin, H.-B.; Zhang, X.-Y.; Feng, C.-F.; Jia, H.-Y.; Zhou, X.-X.; Danzengluobu; Chen, T.-L.; Labaciren; Liu, M.-Y.; Gao, Q.; Zhaxiciren

    2016-06-01

    Since 2014, a new hybrid experiment consisting of a high-energy air-shower-core array (YAC-II), a high-density air-shower array (Tibet-III) and a large underground water-Cherenkov muon-detector array (MD) has been continued by the Tibet ASγ collaboration to measure the chemical composition of cosmic rays in the wide energy range including the ``knee''. In this experiment, YAC-II is used to select high energy core events induced by cosmic rays in the above energy region, while MD is used to estimate the type of nucleus of primary particles by measuring the number of muons contained in the air showers. However, the dynamic range of each MD cell is only 5 to 2000 photoelectrons (PEs) which is mainly designed for observation of high-energy celestial gamma rays. In order to obtain the primary proton, helium and iron spectra and their ``knee'' positions with energy up to 1016 eV, each of PMTs equipped to the MD cell is required to measure the number of photons capable of covering a wide dynamic range of 100-106 PEs according to Monte Carlo simulations. In this paper, we firstly compare the characteristic features between R5912-PMT made by Japan Hamamatsu and CR365-PMT made by Beijing Hamamatsu. If there exists no serious difference, we will then add two 8-inch-in-diameter PMTs to meet our requirements in each MD cell, which are responsible for the range of 100-10000 PEs and 2000-1000000 PEs, respectively. That is, MD cell is expected to be able to measure the number of muons over 6 orders of magnitudes.

  20. Photomultiplier tube selection for the Wide Field of view Cherenkov/fluorescence Telescope Array of the Large High Altitude Air Shower Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Maomao, E-mail: gemaomao@ynu.edu.cn [Department of Physics, Yunnan University, Kunming 650091 (China); Key Laboratory of Astroparticle Physics of Yunnan Province, Kunming 650091 (China); Zhang, Li, E-mail: lizhang@ynu.edu.cn [Department of Physics, Yunnan University, Kunming 650091 (China); Key Laboratory of Astroparticle Physics of Yunnan Province, Kunming 650091 (China); Chen, Yingtao [Department of Physics, Yunnan University, Kunming 650091 (China); Key Laboratory of Astroparticle Physics of Yunnan Province, Kunming 650091 (China); Cao, Zhen; Zhang, Shoushan; Wang, Chong; Bi, Baiyang [Institute of High Energy Physics, CAS, Beijing 100049 (China)

    2016-05-21

    For the purpose of selecting the most suitable photomultiplier tubes (PMTs) for the Wide Field of view Cherenkov/fluorescence Telescope Array (WFCTA), we have performed extensive tests on seven models of 25.4 mm PMTs: Hamamatsu R1924A and R7899, Beijing Hamamatsu CR303, CR332A and CR364, and HZC Photonics XP3102 and XP3182. A dedicated test system has been developed to measure the PMT characteristics such as single photo-electron spectrum, gain, linearity, and spatial uniformity of anode output. The XP3182 and CR364 (R7899) tubes both meet the pivotal requirement due to their superior pulse linearity. The PMT test system, techniques used for these measurements, and their results are also reported.

  1. Photomultiplier tube selection for the Wide Field of view Cherenkov/fluorescence Telescope Array of the Large High Altitude Air Shower Observatory

    Science.gov (United States)

    Ge, Maomao; Zhang, Li; Chen, Yingtao; Cao, Zhen; Zhang, Shoushan; Wang, Chong; Bi, Baiyang

    2016-05-01

    For the purpose of selecting the most suitable photomultiplier tubes (PMTs) for the Wide Field of view Cherenkov/fluorescence Telescope Array (WFCTA), we have performed extensive tests on seven models of 25.4 mm PMTs: Hamamatsu R1924A and R7899, Beijing Hamamatsu CR303, CR332A and CR364, and HZC Photonics XP3102 and XP3182. A dedicated test system has been developed to measure the PMT characteristics such as single photo-electron spectrum, gain, linearity, and spatial uniformity of anode output. The XP3182 and CR364 (R7899) tubes both meet the pivotal requirement due to their superior pulse linearity. The PMT test system, techniques used for these measurements, and their results are also reported.

  2. (Hybrid) Baryons in the Flux-Tube Model

    CERN Document Server

    Page, P R

    1999-01-01

    We construct baryons and hybrid baryons in the non-relativistic flux-tube model of Isgur and Paton. The motion of the flux-tube with the three quark positions fixed, except for centre of mass corrections, is discussed. It is shown that the problem can to an excellent approximation be reduced to the independent motion of a junction and strings.

  3. Measurements of the position-dependent photo-detection sensitivity of the Hamamatsu R11410 and R8520 photomultiplier tubes

    CERN Document Server

    Baudis, L; Kessler, G; Kish, A; Wulf, J

    2015-01-01

    The Hamamatsu R11410 and R8520 photomultipliers (PMTs) are designed for applications in xenon-based dark matter detectors, featuring sensitivity to VUV light and stable operability at cryogenic temperatures. For eleven R11410 and seven R8520 PMTs, the relative photo-detection sensitivity at 470 nm was measured as a function of the position of the incident light on the photocathode. Typical non-uniformity values, considering 80 % of the photocathode surfaces, are 5 % - 10 % and 25 % - 30 % for the R11410 and R8520 types, respectively. It was found that the non-uniformity in the inner region of the photocathode is dominated by light reflections on the inner parts of the photosensors and the border regions contribute most to the observed non-uniformity.

  4. A Readout ASICDesigned For Multi-anode Photomultiplier Tube%多阳极光电倍增管读出ASIC设计

    Institute of Scientific and Technical Information of China (English)

    肖腾飞; 张研; 王庆娟; 吴文欢; 王铮; 赵京伟

    2012-01-01

    主要介绍了针对多阳极光电倍增管读出ASIC设计,该设计主要应用于散裂中子源中子谱仪中的高通量粉末衍射仪的读出电子学系统中[1].设计采用了Chartered 0.35 μm CMOS工艺,整个芯片集成了32通道,每个通道包含前置放大器、积分电路以及比较器等部分,分别实现快速放大、积分、甄别和整形输出等功能.要求前放增益可调,能够准确分辨出中子和γ信号.%It mainly introduces a readout ASIC designed for a multi - anode photomultiplier tube, which is mainly applied to the hash neutron source neutron spectrometer of high flux powder diffraction readout system. This design using the Chartered 0. 35 μm CMOS process, integrates 32 channels, each channel containing a preamplifier, a shaper and a discriminator, to achieve rapid amplification, shaping, discrimination and shaping output. Adjustable gain of preamplifier and accurately to distinguish neutron and gamma signal are required.

  5. Photomultipliers on an LHCb calorimeter

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    An engineer attaches photomultiplier tubes to the electromagnetic calorimeter on the LHCb experiment. These large wall detectors will be used to study the bottom quark, a heavy, short-lived version of quarks found in protons and neutrons. The electromagnetic calorimeter will be used to detect photons, electrons and positrons produced by the decay of these short-lived quarks.

  6. A new Design for an High Gain Vacuum Photomultiplier: The Silicon PMT Used as Amplification Stage

    Energy Technology Data Exchange (ETDEWEB)

    Barbarino, Giancarlo [Universita di Napoli ' Federico II' , Dipartimento di Scienze fisiche, via Cintia 80126 Napoli (Italy); Asmundis, Riccardo de; De Rosa, Gianfranca [Istituto Nazionale di fisica Nucleare, sezione di Napoli, Complesso di Monte S. Angelo Ed. 6, via Cintia 80126 Napoli (Italy); Fiorillo, Giuliana; Russo, Stefano [Universita di Napoli ' Federico II' , Dipartimento di Scienze fisiche, via Cintia 80126 Napoli (Italy)

    2009-12-15

    Photons detection will continue to be a channel of great interest in the High Energy Physics and Astroparticle Physics fields for medium and big scale experiments in the next future. Thus, new solutions for photon detectors, that overcome the current limits of classical photomultipliers, are welcomed. We propose an innovative design for a hybrid, modern, high gain Vacuum Silicon Photomultiplier Tube (VSiPMT) which is boosted by the recent Geiger-mode avalanche silicon photodiode (G-APD) for which a massive production is today available.

  7. A high efficiency hybrid stirling-pulse tube cryocooler

    Science.gov (United States)

    Wang, Xiaotao; Zhang, Yibing; Li, Haibing; Dai, Wei; Chen, Shuai; Lei, Gang; Luo, Ercang

    2015-03-01

    This article presented a hybrid cryocooler which combines the room temperature displacers and the pulse tube in one system. Compared with a traditional pulse tube cryocooler, the system uses the rod-less ambient displacer to recover the expansion work from the pulse tube cold end to improve the efficiency while still keeps the advantage of the pulse tube cryocooler with no moving parts at the cold region. In the meantime, dual-opposed configurations for both the compression pistons and displacers reduce the cooler vibration to a very low level. In the experiments, a lowest no-load temperature of 38.5 K has been obtained and the cooling power at 80K was 26.4 W with an input electric power of 290 W. This leads to an efficiency of 24.2% of Carnot, marginally higher than that of an ordinary pulse tube cryocooler. The hybrid configuration herein provides a very competitive option when a high efficiency, high-reliability and robust cryocooler is desired.

  8. A high efficiency hybrid stirling-pulse tube cryocooler

    Directory of Open Access Journals (Sweden)

    Xiaotao Wang

    2015-03-01

    Full Text Available This article presented a hybrid cryocooler which combines the room temperature displacers and the pulse tube in one system. Compared with a traditional pulse tube cryocooler, the system uses the rod-less ambient displacer to recover the expansion work from the pulse tube cold end to improve the efficiency while still keeps the advantage of the pulse tube cryocooler with no moving parts at the cold region. In the meantime, dual-opposed configurations for both the compression pistons and displacers reduce the cooler vibration to a very low level. In the experiments, a lowest no-load temperature of 38.5 K has been obtained and the cooling power at 80K was 26.4 W with an input electric power of 290 W. This leads to an efficiency of 24.2% of Carnot, marginally higher than that of an ordinary pulse tube cryocooler. The hybrid configuration herein provides a very competitive option when a high efficiency, high-reliability and robust cryocooler is desired.

  9. Silicon photomultiplier readout of NeuLAND

    Energy Technology Data Exchange (ETDEWEB)

    Reinicke, Stefan; Cowan, Thomas E. [Helmholtz-Zentrum Dresden-Rossendorf (Germany); TU Dresden (Germany); Bemmerer, Daniel; Gohl, Stefan; Heidel, Klaus; Roeder, Marko; Stach, Daniel; Wagner, Andreas; Weinberger, David [Helmholtz-Zentrum Dresden-Rossendorf (Germany); Reinhardt, Tobias P. [TU Dresden (Germany); Helmholtz-Zentrum Dresden-Rossendorf (Germany); Zuber, Kai [TU Dresden (Germany); Collaboration: R3B-Collaboration

    2015-07-01

    Recent developements in the field of Silicon Photomultipliers indicate that they could be a potential alternative to the use of photomultiplier tubes for the detection of scintillation light at upcoming large neutron time-of-flight detectors like NeuLAND at FAIR. With a focus on timing resolution, Silicon Photomultipliers from various manufacturers with active surfaces ranging from 1 x 1 mm{sup 2} to 6 x 6 mm{sup 2} were studied using inhouse developed preamplifier boards and a picosecond laser system. Tests were performed with small and large scale scintillators at the electron accelerator ELBE. The data are compared with Monte Carlo simulations.

  10. Repair boundary for parent tube indications within the upper joint zone of hybrid expansion joint (HEJ) sleeved tubes

    Energy Technology Data Exchange (ETDEWEB)

    Cullen, W.K.; Keating, R.F. [Westinghouse Electric, Pittsburgh, PA (United States)

    1997-02-01

    In the Spring and Fall of 1994, and the Spring of 1995, crack-like indications were found in the upper hybrid expansion joint (HEJ) region of Steam Generator (S/G) tubes which had been sleeved using Westinghouse HEJ sleeves. As a result of these findings, analytic and test evaluations were performed to assess the effect of the degradation on the structural, and leakage, integrity of the sleeve/tube joint relative to the requirements of the United States Nuclear Regulatory Commission`s (NRC) draft Regulatory Guide (RG) 1.121. The results of these evaluations demonstrated that tubes with implied or known crack-like circumferential parent tube indications (PTIs) located 1.1 inches or farther below the bottom of the hardroll upper transition, have sufficient, and significant, integrity relative to the requirements of RG 1.121. Thus, the purpose of this report is to provide background information related to the justification of the modified tube repair boundary.

  11. Behaviour of hybrid jute-glass/epoxy composite tubes subjected to lateral loading

    Science.gov (United States)

    Khalid, A. A.

    2015-12-01

    Experimental work on hybrid and non-hybrid composite tubes subjected to lateral loading has been carried out using jute, glass and hybrid jute-glass/epoxy materials. Tubes of 200 mm length with 110 mm inner diameter were fabricated by hand lay-up method to investigate the effect of material used and the number of layers on lateral-load-displacement relations and on the failure mode. Crush force efficiency and the specific energy absorption of the composite tubes were calculated. Results show that the six layers glass/epoxy tubes supported load higher 10.6% than that of hybrid jute-glass/ epoxy made of two layers of jute/epoxy four layers of glass/epoxy. It has been found that the specific energy absorption of the glass/epoxy tubes is found higher respectively 11.6% and 46% than hybrid jute-glass/epoxy and jute/epoxy tubes. The increase in the number of layers from two to six increases the maximum lateral load from 0.53KN to 1.22 KN for jute/epoxy and from 1.35 KN to 3.87 KN for the glass/epoxy tubes. The stacking sequence of the hybrid tubes influenced on the maximum lateral load and the absorbed energy. The maximum load obtained for the six layers jute-glass/epoxy tubes of different staking sequence varies between 1.88 KN to 3.46 KN. Failure mechanisms of the laterally loaded composite tubes were also observed and discussed.

  12. The photomultiplier handbook

    CERN Document Server

    Wright, A G

    2017-01-01

    Photomultipliers are extremely sensitive light detectors that can detect single photons. In multiplying the charge produced by incident light by up to 100 million times, these devices are essential to a wide range of functions, from medical instrumentation to astronomical observations. This complete and authoritative guide will provide students, practitioners, and researchers with a deeper understanding of the operating principles of these devices. Authored by an experienced user and manufacturer of photomultipliers, this handbook gives the reader insights into photomultiplier behaviour as a means to optimize performance. Diffuse and low level light sources are best served with a photomultiplier for the detection of single photon emissions. Light detection and electron multiplication are statistical in nature and the mathematics of these processes is derived from first principles. The book covers other related topics such as scintillation counting, light guides, and large area detectors. The usually complicat...

  13. Application of silicon photomultipliers to positron emission tomography.

    Science.gov (United States)

    Roncali, Emilie; Cherry, Simon R

    2011-04-01

    Historically, positron emission tomography (PET) systems have been based on scintillation crystals coupled to photomultipliers tubes (PMTs). However, the limited quantum efficiency, bulkiness, and relatively high cost per unit surface area of PMTs, along with the growth of new applications for PET, offers opportunities for other photodetectors. Among these, small-animal scanners, hybrid PET/MRI systems, and incorporation of time-of-flight information are of particular interest and require low-cost, compact, fast, and magnetic field compatible photodetectors. With high quantum efficiency and compact structure, avalanche photodiodes (APDs) overcome several of the drawbacks of PMTs, but this is offset by degraded signal-to-noise and timing properties. Silicon photomultipliers (SiPMs) offer an alternative solution, combining many of the advantages of PMTs and APDs. They have high gain, excellent timing properties and are insensitive to magnetic fields. At the present time, SiPM technology is rapidly developing and therefore an investigation into optimal design and operating conditions is underway together with detailed characterization of SiPM-based PET detectors. Published data are extremely promising and show good energy and timing resolution, as well as the ability to decode small scintillator arrays. SiPMs clearly have the potential to be the photodetector of choice for some, or even perhaps most, PET systems.

  14. Detection and analysis system for hybridization images of lab-in-a-tube microarray

    Institute of Scientific and Technical Information of China (English)

    LIU Quanjun; ZHOU Qin; BAI Yunfei; GE Qinyu; LU Zuhong

    2005-01-01

    A lab-in-a-tube microarray system is developed for sample inspection and signal detection by fabricating a flat transparent window cap of the Eppendorf tube. The oli- gonucleotide microarray is immobilized on the inner surface of the cap. A small vessel is placed in an Eppendorf tube for storing hybridization solutions. With the microarray system, the full biochemical processes, including gene fragment amplification, fluorescence labeling, hybridization, and fluorescence detection, have been performed in the sealed tube without opening the cap. The images are obtained from a fluorescence microscope and captured by a CCD, and the data are transported to a computer through the universal serial bus (USB). After noise reduction, signal intensity is determined from hybridization image and the presence of gene fragments is identified. The final data output includes sample information, process steps, and hybridization results. A lab-in- a-tube microarray system for detecting ten respiratory viruses at a single detection is designed. High detection throug- hput and accuracy have been demonstrated with the system.

  15. Effect of Hybridized Fiber Wrapped Around the Aluminum Tubes on the Crushing Performances

    Science.gov (United States)

    Ismail, A. E.; Noranai, Z.; Mohd Nor, N. H.; Mohd Tobi, A. L.; Ahmad, M. H.

    2016-11-01

    Nowadays, synthetic fibres for an example glass fibres is frequently used to wrap the metallic tubes in order to increase their load-bearing capacity. Due to environmental considerations and non-biodegradable behaviour, natural fibres or materials are increasingly used to replace synthetic fibres. The use of synthetic fibres can be minimized by combining them with natural fibres. Based on the literature survey, combining both fibres (synthetic and natural) for crushing applications are relatively new and therefore the main work of this paper is to present the crushing performances of hybridized fibres wrapped around the aluminium tubes when subjected to quasi-static crushing forces. Glass fibres are then combined with yarn kenaf fibres according to these volume fractions: 0, 25, 50, 75 and 100%. The hybridized fibres are wrapped around the tubes twice using different orientations [0o/0o], [15°/-15°], [30o/-30o] and [45o/-45o] included empty tubes before they are immersed into polyester resin bath. The composite tubes are then quasi-statically compressed using a constant cross-head displacement of 10mm/min. The force-displacement curves for each tube conditions are recorded automatically and analysed. The relation between hybridized fibbers and fibre orientations with crashworthiness parameters are investigated and discussed associating with their crushing mechanisms.

  16. Hybrid photon detectors

    CERN Document Server

    D'Ambrosio, C

    2003-01-01

    Hybrid photon detectors detect light via vacuum photocathodes and accelerate the emitted photoelectrons by an electric field towards inversely polarized silicon anodes, where they are absorbed, thus producing electron-hole pairs. These, in turn, are collected and generate electronic signals on their ohmic contacts. This review first describes the characteristic properties of the main components of hybrid photon detectors: light entrance windows, photocathodes, and silicon anodes. Then, essential relations describing the trajectories of photoelectrons in electric and magnetic fields and their backscattering from the silicon anodes are derived. Depending on their anode configurations, three families of hybrid photon detectors are presented: hybrid photomultiplier tubes with single anodes for photon counting with high sensitivity and for gamma spectroscopy; multi-anode photon detector tubes with anodes subdivided into square or hexagonal pads for position-sensitive photon detection; imaging silicon pixel array t...

  17. Geneva University - Silicon photomultiplier : features and applications

    CERN Multimedia

    Université de Genève

    2012-01-01

    GENEVA UNIVERSITY École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92   Wednesday 7 March 2012 SEMINAIRE DE PHYSIQUE CORPUSCULAIRE 11.15 a.m. - Science II, Auditoire 1S081, 30, quai Ernest-Ansermet, 1211 Genève 4 SILICON PHOTOMULTIPLIER : FEATURES AND APPLICATIONS Dr Giulio SARACINO   University of Naples, Federico II   Silicon photomultipliers were developed about ten years ago and their use, unlike traditional photomultiplier tubes, is increasing more and more. They are an evolution of the avalanche photodiode working in Geiger mode regime. Hundreds of such diodes are connected in parallel, allowing single photon response, high detection efficiency, high gain at low bias voltage and very good timing performance. In spite of their Geiger regime, they can be considered linear devices, until the number of photon...

  18. A method to stabilise the performance of negatively fed KM3NeT photomultipliers

    Science.gov (United States)

    Adrián-Martínez, S.; Ageron, M.; Aiello, S.; Albert, A.; Ameli, F.; Anassontzis, E. G.; Andre, M.; Androulakis, G.; Anghinolfi, M.; Anton, G.; Ardid, M.; Avgitas, T.; Barbarino, G.; Barbarito, E.; Baret, B.; Barrios-Martí, J.; Belias, A.; Berbee, E.; van den Berg, A.; Bertin, V.; Beurthey, S.; van Beveren, V.; Beverini, N.; Biagi, S.; Biagioni, A.; Billault, M.; Bondì, M.; Bormuth, R.; Bouhadef, B.; Bourlis, G.; Bourret, S.; Boutonnet, C.; Bouwhuis, M.; Bozza, C.; Bruijn, R.; Brunner, J.; Buis, E.; Buompane, R.; Busto, J.; Cacopardo, G.; Caillat, L.; Calamai, M.; Calvo, D.; Capone, A.; Caramete, L.; Cecchini, S.; Celli, S.; Champion, C.; Cherubini, S.; Chiarella, V.; Chiarelli, L.; Chiarusi, T.; Circella, M.; Classen, L.; Cobas, D.; Cocimano, R.; Coelho, J. A. B.; Coleiro, A.; Colonges, S.; Coniglione, R.; Cordelli, M.; Cosquer, A.; Coyle, P.; Creusot, A.; Cuttone, G.; D'Amato, C.; D'Amico, A.; D'Onofrio, A.; De Bonis, G.; De Sio, C.; Di Capua, F.; Di Palma, I.; Distefano, C.; Donzaud, C.; Dornic, D.; Dorosti-Hasankiadeh, Q.; Drakopoulou, E.; Drouhin, D.; Durocher, M.; Eberl, T.; Eichie, S.; van Eijk, D.; El Bojaddaini, I.; Elsaesser, D.; Enzenhöfer, A.; Favaro, M.; Fermani, P.; Ferrara, G.; Frascadore, G.; Furini, M.; Fusco, L. A.; Gal, T.; Galatà, S.; Garufi, F.; Gay, P.; Gebyehu, M.; Giacomini, F.; Gialanella, L.; Giordano, V.; Gizani, N.; Gracia, R.; Graf, K.; Grégoire, T.; Grella, G.; Grmek, A.; Guerzoni, M.; Habel, R.; Hallmann, S.; van Haren, H.; Harissopulos, S.; Heid, T.; Heijboer, A.; Heine, E.; Henry, S.; Hernández-Rey, J. J.; Hevinga, M.; Hofestädt, J.; Hugon, C. M. F.; Illuminati, G.; James, C. W.; Jansweijer, P.; Jongen, M.; de Jong, M.; Kadler, M.; Kalekin, O.; Kappes, A.; Katz, U. F.; Keller, P.; Kieft, G.; Kießling, D.; Koffeman, E. N.; Kooijman, P.; Kouchner, A.; Kreter, M.; Kulikovskiy, V.; Lahmann, R.; Lamare, P.; Leisos, A.; Leonora, E.; Clark, M. Lindsey; Liolios, A.; Llorens Alvarez, C. D.; Lo Presti, D.; Löhner, H.; Lonardo, A.; Lotze, M.; Loucatos, S.; Maccioni, E.; Mannheim, K.; Manzali, M.; Margiotta, A.; Margotti, A.; Marinelli, A.; Mariš, O.; Markou, C.; Martínez-Mora, J. A.; Martini, A.; Marzaioli, F.; Mele, R.; Melis, K. W.; Michael, T.; Migliozzi, P.; Migneco, E.; Mijakowski, P.; Miraglia, A.; Mollo, C. M.; Mongelli, M.; Morganti, M.; Moussa, A.; Musico, P.; Musumeci, M.; Nicolau, C. A.; Olcina, I.; Olivetto, C.; Orlando, A.; Orzelli, A.; Pancaldi, G.; Paolucci, A.; Papaikonomou, A.; Papaleo, R.; Păvălaš, G. E.; Peek, H.; Pellegrini, G.; Pellegrino, C.; Perrina, C.; Pfutzner, M.; Piattelli, P.; Pikounis, K.; Poma, G. E.; Popa, V.; Pradier, T.; Pratolongo, F.; Pühlhofer, G.; Pulvirenti, S.; Quinn, L.; Racca, C.; Raffaelli, F.; Randazzo, N.; Real, D.; Resvanis, L.; Reubelt, J.; Riccobene, G.; Rossi, C.; Rovelli, A.; Saldaña, M.; Salvadori, I.; Samtleben, D. F. E.; Sánchez García, A.; Sánchez Losa, A.; Sanguineti, M.; Santangelo, A.; Santonocito, D.; Sapienza, P.; Schimmel, F.; Schmelling, J.; Schnabel, J.; Sciacca, V.; Sedita, M.; Seitz, T.; Sgura, I.; Simeone, F.; Sipala, V.; Spisso, B.; Spurio, M.; Stavropoulos, G.; Steijger, J.; Stellacci, S. M.; Stransky, D.; Taiuti, M.; Tayalati, Y.; Terrasi, F.; Tézier, D.; Theraube, S.; Timmer, P.; Töonnis, C.; Trasatti, L.; Travaglini, R.; Trovato, A.; Tsirigotis, A.; Tzamarias, S.; Tzamariudaki, E.; Vallage, B.; Van Elewyck, V.; Vermeulen, J.; Versari, F.; Vicini, P.; Viola, S.; Vivolo, D.; Volkert, M.; Wiggers, L.; Wilms, J.; de Wolf, E.; Zachariadou, K.; Zani, S.; Zornoza, J. D.; Zúñiga, J.

    2016-12-01

    The KM3NeT research infrastructure, currently under construction in the Mediterranean Sea, will host neutrino telescopes for the identification of neutrino sources in the Universe and for studies of the neutrino mass hierarchy. These telescopes will house hundreds of thousands of photomultiplier tubes that will have to be operated in a stable and reliable fashion. In this context, the stability of the dark counts has been investigated for photomultiplier tubes with negative high voltage on the photocathode and held in insulating support structures made of 3D printed nylon material. Small gaps between the rigid support structure and the photomultiplier tubes in the presence of electric fields can lead to discharges that produce dark count rates that are highly variable. A solution was found by applying the same insulating varnish as used for the high voltage bases directly to the outside of the photomultiplier tubes. This transparent conformal coating provides a convenient and inexpensive method of insulation.

  19. Effect of the braiding angle on the energy absorption properties of a hybrid braided FRP tube

    Energy Technology Data Exchange (ETDEWEB)

    Okano, M.; Sugimoto, K. [Kyoto Institute of Technology, Kyoto (Japan). Div. of Advanced Fibro Science; Saito, H. [Kanazawa Institute of Technology, Kanazawa (Japan); Nakai, A.; Hamada, H. [Kyoto Institute of Technology, Kyoto (Japan)

    2005-07-01

    Energy absorption is achieved by the combination of various fracture mechanisms such as fibre fracture, delamination, and central crack. However, serious problems would arise if this energy absorption ability were compromised by brittle crack propagation of the cross-sectional central part. In a previous study, the use of flexible resin with lower stiffness and higher toughness than the resin generally used was suggested as a method to restrain brittle crack propagation. In this study, hybrid braided fibre reinforced plastic (FRP) tubes were fabricated according to the previous study involving FRP rods. In this case, the flexible resin was applied to middle-end-fibre. The energy absorption characteristics and crushing mechanisms based on precise cross-sectional observation of the crush zone of the braided FRP tubes with or without the presence of flexible resin in middle-end-fibre were investigated. It was found that braided FRP tubes with or without the presence of flexible resin in middle-end-fibre were investigated. It was found that braided FRP tube with a 30{sup o} braiding angle, together with the presence of flexible resins, shows significant improvement in terms of energy absorption ability. The added flexibility of the tubes owing to the addition of flexible resin in turn causes short cracks, more fibre breakage, and consequently enhanced energy absorption properties. (author)

  20. Tests of silicon photomultipliers for NeuLAND

    Energy Technology Data Exchange (ETDEWEB)

    Reinhardt, Tobias; Roeder, Marko [Institut fuer Kern- und Teilchenphysik, Technische Universitaet Dresden (Germany); Bemmerer, Daniel; Elekes, Zoltan; Heidel, Klaus; Kempe, Mathias; Stach, Daniel; Wagner, Andreas [Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Germany); Cowan, Thomas [Institut fuer Kern- und Teilchenphysik, Technische Universitaet Dresden (Germany); Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Germany)

    2013-07-01

    For upcoming large-scale neutron time-of-flight detectors like NeuLAND at FAIR the use of photomultiplier tubes is still state-of-the-art for the detection of the scintillation light. However, recent developments in the field of Silicon Photomultiplier indicate that they may also be suitable for this type of application. 3 x 3 mm{sup 2} prototypes from various manufacturers were tested with small scale scintillators and a Sr-90 source. Using inhouse developed preamplifier boards, first time resolution measurements with a 270 cm long NeuLAND BC-408 scintillation bar were carried out at the electron accelerator ELBE.

  1. Parametric study and performance analysis of hybrid rocket motors with double-tube configuration

    Science.gov (United States)

    Yu, Nanjia; Zhao, Bo; Lorente, Arnau Pons; Wang, Jue

    2017-03-01

    The practical implementation of hybrid rocket motors has historically been hampered by the slow regression rate of the solid fuel. In recent years, the research on advanced injector designs has achieved notable results in the enhancement of the regression rate and combustion efficiency of hybrid rockets. Following this path, this work studies a new configuration called double-tube characterized by injecting the gaseous oxidizer through a head end injector and an inner tube with injector holes distributed along the motor longitudinal axis. This design has demonstrated a significant potential for improving the performance of hybrid rockets by means of a better mixing of the species achieved through a customized injection of the oxidizer. Indeed, the CFD analysis of the double-tube configuration has revealed that this design may increase the regression rate over 50% with respect to the same motor with a conventional axial showerhead injector. However, in order to fully exploit the advantages of the double-tube concept, it is necessary to acquire a deeper understanding of the influence of the different design parameters in the overall performance. In this way, a parametric study is carried out taking into account the variation of the oxidizer mass flux rate, the ratio of oxidizer mass flow rate injected through the inner tube to the total oxidizer mass flow rate, and injection angle. The data for the analysis have been gathered from a large series of three-dimensional numerical simulations that considered the changes in the design parameters. The propellant combination adopted consists of gaseous oxygen as oxidizer and high-density polyethylene as solid fuel. Furthermore, the numerical model comprises Navier-Stokes equations, k-ε turbulence model, eddy-dissipation combustion model and solid-fuel pyrolysis, which is computed through user-defined functions. This numerical model was previously validated by analyzing the computational and experimental results obtained for

  2. Modeling wall effects in a micro-scale shock tube using hybrid MD-DSMC algorithm

    Science.gov (United States)

    Watvisave, D. S.; Puranik, B. P.; Bhandarkar, U. V.

    2016-07-01

    Wall effects in a micro-scale shock tube are investigated using the Direct Simulation Monte Carlo method as well as a hybrid Molecular Dynamics-Direct Simulation Monte Carlo algorithm. In the Direct Simulation Monte Carlo simulations, the Cercignani-Lampis-Lord model of gas-surface interactions is employed to incorporate the wall effects, and it is shown that the shock attenuation is significantly affected by the choice of the values of tangential momentum accommodation coefficient. A loosely coupled Molecular Dynamics-Direct Simulation Monte Carlo approach is then employed to demonstrate incomplete accommodation in micro-scale shock tube flows. This approach uses fixed values of the accommodation coefficients in the gas-surface interaction model, with their values determined from a separate dynamically similar Molecular Dynamics simulation. Finally, a completely coupled Molecular Dynamics-Direct Simulation Monte Carlo algorithm is used, wherein the bulk of the flow is modeled using Direct Simulation Monte Carlo, while the interaction of gas molecules with the shock tube walls is modeled using Molecular Dynamics. The two regions are separate and coupled both ways using buffer zones and a bootstrap coupling algorithm that accounts for the mismatch of the number of molecules in both regions. It is shown that the hybrid method captures the effect of local properties that cannot be captured using a single value of accommodation coefficient for the entire domain.

  3. Solid-State Photomultiplier Development for Radiation Detection

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Stuart [NSTec; Brown, Kristina [NSTec; Curtis, Alden [NSTec; Young, Jason [NSTec; Guise, Ronald [NSTec

    2012-06-12

    We are pursuing the sensitivity of back-thinned silicon (BT Si) with the gain of an SSPM (Baker 2011). Working in collaboration with Radiation Monitoring Devices, Inc., we are designing and fabricating prototype devices. Our original idea spurred from hybrid designs of advanced image sensors that use the sensitivity of BT Si that is then bump bonded to a CMOS readout device. As shown in the graph below (right), the BT Si has a far superior quantum efficiency (QE) than the standard photocathode response available in photomultiplier tubes (PMTs). Collecting as many scintillation photons as possible is the first objective. There has been major concern that the prototype could not deliver the ~105 electronic gain of a PMT. However, recently developed SSPMs do provide the electronic gain needed. We are now pursuing the design of a BTSSPM. With a smaller footprint, the SSPM can potentially lead to a simple, compact deployment package. Because the SSPM can be pixelated and tiled, we foresee developing an imaging detector. Pinhole imaging of radiation sources is a well-exercised technology. Our implementation of the coded aperture (Marks 2010) imager provides a high throughput pinhole imager. We intend to apply miniature coded apertures to minimal pixel count SSPMs to evaluate image quality.

  4. Crash worthy capacity of a hybridized epoxy-glass fiber aluminum columnar tube using repeated axial resistive force

    Energy Technology Data Exchange (ETDEWEB)

    Paruka, Perowansa [Jalan Politeknik, Kota Kinabalu (Malaysia); Siswanto, Waluyo Adi [Universiti Tun Hussein Onn Malaysia, Parit Raja (Malaysia); Maleque, Md Abdul [Universiti Islam Antarabangsa Malaysia, Kuala Lumpur (Malaysia); Shah, Mohd Kamal Mohd [Universiti Malaysia Sabah, Kota Kinabalu (Malaysia)

    2015-05-15

    A combination of aluminum columnar member with composite laminate to form a hybrid structure can be used as collapsible energy absorbers especially in automotive vehicular structures to protect occupants and cargo. A key advantage of aluminum member in composite is that it provides ductile and stable plastic collapse mechanisms with progressive deformation in a stable manner by increasing energy absorption during collision. This paper presents an experimental investigation on the influence of the number of hybrid epoxy glass layers in overwrap composite columnar tubes. Three columnar tube specimens were used and fabricated by hand lay-up method. Aluminum square hollow shape was combined with externally wrapped by using an isophthalic epoxy resin reinforced with glass fiber skin with an orientation angle of 0 .deg. /90 .deg. The aluminum columnar tube was used as reference material. Crushed hybrid-composite columnar tubes were prepared using one, two, and three layers to determine the crash worthy capacity. Quasi-static crush test was conducted using INSTRON machine with an axial loading. Results showed that crush force and the number of layers were related to the enhancement of energy absorption before the collapse of columnar tubes. The energy absorption properties of the crushed hybrid-composite columnar tubes improved significantly with the addition of layers in the overwrap. Microscopic analysis on the modes of epoxy-glass fiber laminate failure was conducted by using scanning electron microscopy.

  5. MAX Phase Modified SiC Composites for Ceramic-Metal Hybrid Cladding Tubes

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Yang-Il; Kim, Sun-Han; Park, Dong-Jun; Park, Jeong-Hwan; Park, Jeong-Yong; Kim, Hyun-Gil; Koo, Yang-Hyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    A metal-ceramic hybrid cladding consists of an inner zirconium tube, and an outer SiC fiber-matrix SiC ceramic composite with surface coating as shown in Fig. 1 (left-hand side). The inner zirconium allows the matrix to remain fully sealed even if the ceramic matrix cracks through. The outer SiC composite can increase the safety margin by taking the merits of the SiC itself. In addition, the outermost layer prevents the dissolution of SiC during normal operation. On the other hand, a ceramic-metal hybrid cladding consists of an outer zirconium tube, and an inner SiC ceramic composite as shown in Fig. 1 (right-hand side). The outer zirconium protects the fuel rod from a corrosion during reactor operation, as in the present fuel claddings. The inner SiC composite, additionally, is designed to resist the severe oxidation under a postulated accident condition of a high-temperature steam environment. Reaction-bonded SiC was fabricated by modifying the matrix as the MAX phase. The formation of Ti{sub 3}SiC{sub 2} was investigated depending on the compositions of the preform and melt. In most cases, TiSi{sub 2} was the preferential phase because of its lowest melting point in the Ti-Si-C system. The evidence of Ti{sub 3}SiC{sub 2} was the connection with the pressurizing.

  6. Thermoregulation of silicon photomultipliers for space

    Energy Technology Data Exchange (ETDEWEB)

    Baldazzi, G.; Foschi, E. [Department of Physics and INFN, Viale B.Pichat 4/2, 40127 Bologna (Italy); Laurenti, G. [INFN of Bologna, Viale B.Pichat 4/2, 40127 Bologna (Italy); Levi, G. [Department of Physics and INFN, Viale B.Pichat 4/2, 40127 Bologna (Italy); Guandalini, C. [INFN of Bologna, Viale B.Pichat 4/2, 40127 Bologna (Italy); Lanconelli, N. [Department of Physics and INFN, Viale B.Pichat 4/2, 40127 Bologna (Italy); Quadrani, L. [INFN of Bologna, Viale B.Pichat 4/2, 40127 Bologna (Italy); Rossi, P. [Department of Physics and INFN, Viale B.Pichat 4/2, 40127 Bologna (Italy); Sbarra, C. [Department of Physics and INFN, Viale B.Pichat 4/2, 40127 Bologna (Italy); Enrico Fermi Research Center, Via Panisperna 89, 06100 Roma (Italy)], E-mail: cristina.sbarra@bo.infn.it; Zuffa, M. [INFN of Bologna, Viale B.Pichat 4/2, 40127 Bologna (Italy)

    2009-10-21

    The silicon photomultiplier (SiPM) has been recently studied in the INFN laboratories of Bologna for Time of Flight (TOF) detectors in space missions. Low consumption, low cost, low weight, resistance to radiation damage and insensitivity to magnetic fields are the advantages that lead to the choice of the SiPM to be used in conjunction with optical fibres for detecting the scintillation light of a space counter. The SiPM response to various light intensities has been studied in laboratory and it was compared to the PM response in order to use it for scintillation light instead of a photomultiplier. The results were confirmed by a Monte Carlo. Nevertheless the SiPM gain depends on temperature and thermal stabilization of the device turns out to be necessary. A hybrid front-end circuit that amplifies the signal while controlling and stabilizing the device temperature has been developed and some tests are shown. A thermal electric cooler (TEC) module based on Peltier cell has been modeled. The TEC module operating in atmosphere showed it can stabilize the temperature of the SiPM to the chosen set-point (9{+-}3 K) in a few seconds.

  7. The Experimental Studies on Behavior of Ultrahigh-Performance Concrete Confined by Hybrid Fiber-Reinforced Polymer Tubes

    Directory of Open Access Journals (Sweden)

    Zong-cai Deng

    2015-01-01

    Full Text Available This paper conducts axial compression test of ultrahigh performance concrete- (UHPC- filled hybrid FRP (HFRP tubes, using the alternating hybrid technology to improve the deformation capacity of FRP tube and measure the axial compressive responses of ultimate strength, strains, and stress-strain curve of confined specimens. The test results show that the local rupture of HFRP tubes did not lead to explosive failure of UHPC cylinder, and its ductility is better than that of UHPC confined by only one type of FRP tube; HFRP tube can effectively improve the compressive strength and ultimate strain of UHPC specimens; the stress-strain curves divide into three distinct regions: linear phase, transition phase, and linear strengthening phase. None of the models provided a reasonable prediction for strength and strain of HFRP-confined UHPC specimen; therefore, a new ultimate strength and strain perdition model considering the confinement effectiveness of different hybrid FRP series was proposed. The new proposed model presented the best fitting results. The stress-strain responses predicted by the existing models are all below the experimental curves; therefore, a new three-stage constitutive model was proposed, which relatively fits the test curves better than the existing models.

  8. Simulation of Silicon Photomultiplier Signals

    NARCIS (Netherlands)

    Seifert, Stefan; van Dam, Herman T.; Huizenga, Jan; Vinke, Ruud; Dendooven, Peter; Loehner, Herbert; Schaart, Dennis R.

    2009-01-01

    In a silicon photomultiplier (SiPM), also referred to as multi-pixel photon counter (MPPC), many Geiger-mode avalanche photodiodes (GM-APDs) are connected in parallel so as to combine the photon counting capabilities of each of these so-called microcells into a proportional light sensor. The

  9. Simulation of silicon photomultiplier signals

    NARCIS (Netherlands)

    Seifert, S.; Van Dam, H.T.; Huizenga, J.; Vinke, R.; Dendooven, P.; Löhner, H.; Schaart, D.R.

    2009-01-01

    In a silicon photomultiplier (SiPM), also referred to as multi-pixel photon counter (MPPC), many Geiger-mode avalanche photodiodes (GM-APDs) are connected in parallel so as to combine the photon counting capabilities of each of these so-called microcells into a proportional light sensor. The

  10. Photon Detection Efficiency Measurements of the VERITAS Cherenkov Telescope Photomultipliers after four Years of Operation

    CERN Document Server

    Gazda, Eliza; Otte, Nepomuk; Richards, Gregory

    2016-01-01

    The photon detection efficiency of two sets of R10560-100-20 superbialkali photomultiplier tubes from Hamamatsu were measured between 200 nm and 750 nm to quantify a possible degradation of the photocathode sensitivity after four years of operation in the cameras of the VERITAS Cherenkov telescopes. A sample of 20 photomultiplier tubes, which was removed from the telescopes was compared with a sample of 20 spare photomultiplier tubes, which had been kept in storage. It is found that the average photocathode sensitivity marginally increased below 300 nm and dropped by 10% to 30% above 500 nm. The average photocathode sensitivity folded with the Cherenkov spectrum emitted by particles in air showers, however, reveals a consistent detection yield of 18.9+/-0.2% and 19.1+/-0.2% for the sample removed from the telescope and the spare sample, respectively.

  11. The IMB photomultiplier test facilityrefid="FN1">*

    Science.gov (United States)

    Wuest, C. R.; Bionta, R. M.; Blewitt, G.; Bratton, C. B.; Cortez, B. G.; Errede, S.; Foster, G. W.; Gajewski, W.; Goldhaber, M.; Greenberg, J.; Jones, T. W.; Kropp, W. R.; Learned, J. G.; Lehmann, E.; LoSecco, J. M.; Ramana Murthy, P. V.; Park, H. S.; Reines, F.; Schultz, J.; Shumard, E.; Sinclair, D.; Smith, D. W.; Sobel, H. W.; Stone, J. L.; Sulak, L. R.; Svoboda, R.; van der Velde, J. C.

    1985-09-01

    An automatic system for testing up to 32 photomultiplier tubes (PMs) simultaneously under single photon counting conditions has been used to measure characteristics of more than 2500 PMs for use in the Irvine-Michigan-Brookhaven (IMB) proton decay experiment, 2048 tubes (64 EMI 9834B 8″ diameter, and 1984 EMI 9870B 5″ diameter) were selected for use in the 8000 m 3 IMB water Cherenkov detector, now in operation for over a year. The PM test system is described and results of testing are presented along with PM performance in the IMB detector over the last year. In general, we find that the tube characteristics have smaller fluctuations than expected and that the tubes have proven to be reliable under rugged handling and operating conditions. On the basis of our experience, we make suggestions as to new industry standards for PMs to be used in particle counting.

  12. Neutron detectors based on CMOS solid state photomultipliers

    Science.gov (United States)

    Sia, Radia; Christian, James F.; Stapels, Christopher J.; Prettyman, Thomas; Squillante, Michael R.

    2008-08-01

    CMOS solid-state photomultipliers (CMOS-SSPM) are new, potentially very inexpensive, photodetectors that have the promise of supplanting photomultiplier tubes and standard photodiodes for many nuclear radiation detection measurements using scintillator crystals. The compact size and very high gain make SSPMs attractive for use in applications where photomultiplier tubes cannot be used and standard photodiodes have insufficient sensitivity. In this effort, the use of SSPMs was investigated for the detection of neutrons with the goal of designing a detector for portable systems that has the capability of discriminating neutrons from gamma rays. The neutron scintillation signatures were measured using boron-loaded plastic scintillators. Our detector concept design incorporates a dual-scintillator design with both a neutrons sensitive organic scintillator (a boron-loaded gel) and a gamma ray sensitive inorganic scintillator (LYSO). Using this design, the gamma ray signal is suppressed and the neutron events are clearly resolved. The design was modeled to optimize the detection efficiency for both thermal and energetic neutrons. In addition, the detection of thermal neutrons in the presence of gamma rays was examined using the SSPM coupled to Cs2LiYCl6:Ce scintillator (CLYC).

  13. Silicon Photomultiplier Characterization for sPHENIX Calorimeters

    Science.gov (United States)

    Tanner, Meghan; Skoby, Michael; Aidala, Christine; Sphenix Collaboration

    2016-09-01

    Silicon photomultipliers (SiPMs) are preferable to photomultiplier tubes due to their small size, insensitivity to magnetic fields, low operating voltage, and capability of detecting single photons. The sPHENIX collaboration at RHIC will use SiPMs in their proposed electromagnetic and hadronic calorimeters. The University of Michigan is assembling and implementing a test stand to characterize the dark count rate, temperature dependence, gain, and photon detection efficiency of SiPMs. To more accurately determine the dark count rate, we have constructed a light tight box to isolate the SiPM, which surrounds an electronics enclosure that protects the SiPM circuitry, and installed software to record the output signals. With this system, we will begin to collect data and optimize the system to test arrays of SiPMs instead of single devices as the proposed calorimeters will require testing approximately 115,000 SiPMs.

  14. 光电倍增管在磷酸液声致发光实验中的应用%Application of photomultiplier tube in the phosphoric acid liquid sonoluminescence

    Institute of Scientific and Technical Information of China (English)

    买买提吐送·买买提明

    2013-01-01

    It is of great importance to measure light intensity in different thickness of liquid,explore movement of cavitation bubble and study luminous mechanism.By using ultrasonic irradiation method,sound luminescence in the phosphoric acid liquid has been achieved and its luminescence feature in different resonant frequency was studied.Using photomultiplier to measure light intensity in the phosphoric acid liquid,it was found that stronger light intensity and good cyclicity can be achieved with liquid thickness of 10cm,driver frequency between f=21.061 kHz and f=20.316 kHz.When thickness of liquid was 3 mm and its frequency was between f=17.91 kHz and f=19 kHz.Its cyclicity was 25 μs and optical signal was stronger.So conclusion is that luminescence intensity and cyclicality in phosphoric acid is closely related to its liquid's thickness and driving frequency.Based on phosphoric acid liquid multiple bubble luminescence,the application of photomultiplier in measurement of light intensity is described in detail and suggestions on its improvement are discussed in this paper.%对不同厚度液体进行光强测量,深入探索空化气泡的运动,研究发光机理很有意义.用超声激励法在磷酸液体中实现多泡声致发光,研究不同共振频率下发光的特点.利用光电倍增管多次测量发光强度相互比较,结果是在液体厚度10 cm、驱动频率f=21.061 kHz和f=20.316 kHz时,周期性较好为50 μs,液体通过漩涡集中气泡可以使更多气泡发光;在液体厚度3mm、驱动频率f=17.91 kHz和f=19 kHz时,周期性很好为25 μs;且光信号都较强.结论是磷酸中声致发光强度、周期与液体厚度、驱动频率密切相关.本文以磷酸液多泡声致发光实验研究为基础,从内部和外部原理来出发,详细介绍了光电倍增管在多泡声致发光光强测量中的实用,为今后研究者提供了一些经验.根据实验过程中遇到的一些实际问题提出了建议和改善意见.

  15. PMm2: large photomultipliers and innovative electronics for the next-generation neutrino experiments

    CERN Document Server

    Genolini, B; Blin, S; Campagne, J -E; Combettes, B; Conforti, S; De-haine, A -G; Duchesneau, D; Dulucq, F; Dumont-Dayot, N; Favier, J; Fouché, F; Hermel, R; de La Taille, C; Martin-Chassard, G; Trung, T Nguyen; Périnet, C; Peyré, J; Pouthas, J; Raux, L; Rindel, E; Rosier, P; Tassan-Viol, J; Wei, W; Zghiche, A

    2008-01-01

    The next generation of proton decay and neutrino experiments, the post-SuperKamiokande detectors as those that will take place in megaton size water tanks, will require very large surfaces of photodetection and a large volume of data. Even with large hemispherical photomultiplier tubes, the expected number of channels should reach hundreds of thousands. A funded R&D program to implement a solution is presented here. The very large surface of photodetection is segmented in macro pixels made of 16 hemispherical (12 inches) photomultiplier tubes connected to an autonomous front-end which works on a triggerless data acquisition mode. The expected data transmission rate is 5 Mb/s per cable, which can be achieved with existing techniques. This architecture allows to reduce considerably the cost and facilitate the industrialization. This document presents the simulations and measurements which define the requirements for the photomultipliers and the electronics. A proto-type of front-end electronics was successf...

  16. Investigating the temperature dependence of photomultiplier quantum efficiency when operating in the visible spectrum

    CERN Document Server

    Clawson, Savannah Ellen

    2017-01-01

    The quantum efficiency of a Burle 8850 photomultiplier tube with a potassium-caesium-antimony (bialkali) photocathode was determined by attenuating a 1 mW HeNe laser emitting at 633 nm and measuring the signal frequency when the laser was incident on the photomultiplier. A temperature range of 5 $^{\\circ}$C $-$ 20 $^{\\circ}$C was investigated and it was found that the quantum efficiency decreases with temperature, with the signal frequency decreasing at a faster rate than the dark current frequency. Therefore, it was concluded that it would not be beneficial to cool photomultiplier tubes operating in the visible spectrum for use in collinear laser spectroscopy due to a decreasing signal-to-noise ratio. The signal pulse height distribution was also analysed and found to be independent of temperature within the range investigated.

  17. Silicon photomultipliers in AMIGA muon counters

    Energy Technology Data Exchange (ETDEWEB)

    Botti, Ana Martina [Institut fuer Kernphysik, Karlsruher Institut fuer Technologie (Germany); Instituto de Tecnologias en Deteccion y Astroparticulas (ITeDA) (Argentina); Collaboration: Pierre-Auger-Collaboration

    2016-07-01

    The project AMIGA (Auger Muons and Infill for the Ground Array) aims to extend the energy range at the Pierre Auger Observatory to observe cosmic rays of lower energies (down to ∝10{sup 17} eV) and to study the transition from extragalactic to galactic cosmic rays. AMIGA is compounded by an infill of surface detectors (employing Cherenkov radiation detection in water) and muon counters. The AMIGA muon counters consist of an array of buried modules composed of 64 scintillator bars, a multi-pixel Photo Multiplier Tube (PMT) and the corresponding electronic of acquisition which works along with the surface detector. Currently, ITeDA is evaluating the feasibility of replacing PMTs with silicon photomultipliers (SiPM) without performing any substantial modification in the digital readout nor in the mechanical design. I present calibration results of a prototype module associated to the surface detector Toune of the Pierre Auger Observatory using a SiPM Hamamatsu S1257-100C plugged to the standard AMIGA front-end electronics. In addition, a study concerning gain stability and temperature variation has also been performed and is reported. I finally discuss a comparison between traces measured by both photodetectors (PMT and SiPM) for modules associated to the surface detector Toune.

  18. Long range hybrid tube-wedge plasmonic waveguide with extreme light confinement and good fabrication error tolerance.

    Science.gov (United States)

    Ding, Li; Qin, Jin; Xu, Kai; Wang, Liang

    2016-02-22

    We studied a novel long range hybrid tube-wedge plasmonic (LRHTWP) waveguide consisting of a high index dielectric nanotube placed above a triangular metal wedge substrate. Using comprehensive numerical simulations on guiding properties of the designed waveguide, it is found that extreme light confinement and low propagation loss are obtained due to strong coupling between dielectric nanotube mode and wedge plasmon polariton. Comparing with previous studied hybrid plasmonic waveguides, the LRHTWP waveguide has longer propagation length and tighter mode confinement. In addition, the LRHTWP waveguide is quite tolerant to practical fabrication errors such as variation of the wedge tip angle and the horizontal misalignment between the nanotube and the metal wedge. The proposed LRHTWP waveguide could have many application potentials for various high performance nanophotonic components.

  19. Analog multiplexer for testing multianode photomultipliers used in AMIGA project of the Pierre Auger Observatory

    Science.gov (United States)

    Lucero, A.; Almela, A.; Suarez, F.; Reyes, C.; Cancio, A.; Fuster, A.; Gallo, F.; Hampel, M. R.; Platino, M.; Videla, M.; Wainberg, O.; Yelos, D.; Etchegoyen, A.

    2015-09-01

    Most particle detectors used in astroparticle physics have an optoelectronic device that senses generated light and converts it into an electrical pulse. Photomultiplier tubes are commonly used, particularly those with multiple anodes. Prior to coupling to a detector system these tubes must be fully characterized, which requires either the same number of data acquisition channels as outputs or a switching-multiplexer system. Given that every project has its own requirements, the testing system must be as flexible as possible. The multiplexer presented here can be used to test silicon photomultipliers or any high-frequency signal. It is a scalable 64 to 4 channel analog device designed for low crosstalk and low attenuation. Results of the application of this multiplexer with a -3 dB bandwidth of 800 MHz are shown by testing 64-channel tubes for the AMIGA project.

  20. LHCb : Behaviour of Multi-anode Photomultipliers in Magnetic Fields for the LHCb RICH Upgrde

    CERN Multimedia

    Gambetta, Silvia

    2015-01-01

    A key feature of the LHCb upgrade, scheduled for 2019, is to remove the first level trigger and its data reduction from 40MHz to 1MHz, which is implemented in the on-detector readout electronics. The consequence for the LHCb Ring Imaging Cherenkov (RICH) detectors is that the Hybrid Photon Detectors need to be replaced as the readout chip is inside the detector vacuum. The baseline for replacement are Multianode Photomultiplier tubes (MaPMT) and new readout electronics. The MaPMTs will be located in the fringe field of the LHCb dipole magnet with residual fields up to 25 G. Therefore, their behaviour in magnetic fields is critical. Here we report about studies of the Hamamatsu models R11265 and H12700 in a magnetic field in an effort to qualify them for use in the LHCb RICH upgrade. Comparisons to the known model R7600 are also made. Measurements of the collection efficiency and gain were performed for all three space directions as a function of the magnetic field strength. In addition to measurements with ba...

  1. Facile synthesis of graphene hybrid tube-like structure for simultaneous detection of ascorbic acid, dopamine, uric acid and tryptophan

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Wen [Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Chai Yaqin, E-mail: yqchai@swu.edu.cn [Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Yuan Ruo, E-mail: yuanruo@swu.edu.cn [Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Chen Shihong; Han Jing; Yuan Dehua [Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China)

    2012-12-05

    Graphical abstract: A tube-like structure of graphene hybrid (GS-PTCA) was synthesized via {pi}-{pi} stacking interaction, and was used as modifier to fabricate electrode for simultaneous detection of ascorbic acid (AA), dopamine (DA), uric acid (UA) and tryptophan (Trp). SEM images of GS, PTCA and GS-PTCA were presented. Under the synergistic effects between GS and PTCA, the modified electrode displayed high catalytic activity and selectivity toward the oxidation of AA, DA, UA, and Trp. Highlights: Black-Right-Pointing-Pointer A simple strategy for simultaneous detection of AA, DA, UA and Trp has been constructed. Black-Right-Pointing-Pointer The tube-like structure of graphene hybrid (GS-PTCA) was synthesized. Black-Right-Pointing-Pointer The GS-PTCA provided a selective interface for discrimination of AA, DA, UA and Trp. - Abstract: In the present work, a tube-like structure of graphene hybrid as modifier to fabricate electrode for simultaneous detection of ascorbic acid (AA), dopamine (DA), uric acid (UA) and tryptophan (Trp) was reported. The hybrid was synthesized by a simple method based on graphene sheets (GS) and 3,4,9,10-perylenetetracarboxylic acid (PTCA) via {pi}-{pi} stacking interaction under ultrasonic condition. The combination of GS and PTCA could effectively improve the dispersion of GS, owing to PTCA with the carboxylic-functionalized interface. Comparing with pure GS or PTCA modified electrode, GS-PTCA displayed high catalytic activity and selectivity toward the oxidation of AA, DA, UA, and Trp. Moreover, cyclic voltammetry, different pulse voltammetry and scanning electron microscopy were employed to characterize the sensors. The experiment results showed that the linear response range for simultaneous detection of AA, DA, UA, and Trp were 20-420 {mu}M, 0.40-374 {mu}M, 4-544 {mu}M and 0.40-138 {mu}M, respectively, and the detection limits were 5.60 {mu}M, 0.13 {mu}M, 0.92 {mu}M and 0.06 {mu}M (S/N = 3). Importantly, the proposed method offers

  2. Silicon photomultiplier timing performance study

    Energy Technology Data Exchange (ETDEWEB)

    Gamal, Ahmed, E-mail: gamal.ahmed@assoc.oeaw.ac.at [Stefan Meyer Institute for Subatomic Physics of the Austrian Academy of Sciences, Vienna (Austria); Al-Azhar University, Faculty of Science, Physics Department, Cairo (Egypt); Paul, Buehler; Johann, Marton; Ken, Suzuki [Stefan Meyer Institute for Subatomic Physics of the Austrian Academy of Sciences, Vienna (Austria)

    2011-10-01

    Many characteristics of Silicon Photomultipliers can be tuned with temperature and operation voltage. We present preliminary results of a study of the effect of these two operation parameters on the time resolution of large active area Multi-Pixel Photon Counters (MPPCs) manufactured by Hamamatsu. Measurements at -10, 0, and 10 deg. C at different bias voltages were performed. The time resolution is best at low temperature and high over-voltage. Most significant improvements can be achieved in cases with low number of fired pixels (<10pixels). Between the worst and best case among the considered conditions a factor of five improvement was observed. In cases with large number of fired pixels (>40pixels) the effect of temperature and operation voltage becomes smaller. The timing performance still improves with decreasing temperature ({approx}factor of 2) but it hardly depends on the operation voltage. The study shows that especially in applications where only few photons are available for detection a careful optimization of temperature and operation voltage are advisable to obtain optimum timing results with the MPPC.

  3. Aspects of chip and cell size of silicon photomultipliers

    Science.gov (United States)

    Iskra, P.; Dietzinger, Christoph; Eggert, T.; Fraczek, M.; Ganka, T.; Höllt, L.; Knobloch, J.; Miyakawa, N.; Pahlke, A.; Wiest, F.; Fojt, R.

    2012-10-01

    Requirements like device miniaturization, insensitivity to magnetic field and cost aspects in the field of low level light detection will lead to a replacement of the conventional photomultiplier tube by Silicon Photomultiplier (SiPM) for several applications in case the photon detection efficiency will be comparably higher at the same price level. This novel solid-state sensor consists of an array of parallel connected avalanche photodiodes operated in limited Geiger-mode. The triggered cells are recovered by an upstream connected quenching resistor. The main characteristics are gain, noise, photon detection efficiency (PDE), dynamic range and time resolution. To meet the requirements of various potential applications, SiPMs need to be available with several micro pixel sizes and total active areas. For this reason KETEK produces devices with microcell pitches from 15μm up to 100μm and total active sensor areas from 1.0 x 1.0 mm2 up to 6.0 mm x 6.0 mm2. The effects of this scaling on the SiPM device parameters are discussed.

  4. SILICON PHOTOMULTIPLIERS FOR MEDICAL IMAGING AND DOSIMETRY-AN OVERVIEW.

    Science.gov (United States)

    Herrnsdorf, L; Caccia, M; Mattsson, S

    2016-06-01

    Silicon photomultipliers (SiPMs) are an enabling solid-state technology for low light sensing, with single photon sensitivity and photon number resolving capability. They feature an extremely high internal gain at the 10(6) level, comparable to photomultiplier tubes (PMTs), with the advantage of low operating voltage (~50 V compared to ~1000 V for PMT) and low energy consumption. The solid-state technology makes SiPMs compact, insensitive to magnetic fields and with an extreme flexibility in the design to cope with different applications. The fast development of the multiplication avalanche opens up the possibility to achieve time resolution at the 30 ps level. Dynamic range is however limited compared to PMT and the dark count rate relatively high, yet today at the level of 50 kHz/mm(2) at room temperature. Interfaced with scintillation material, SiPMs provide a powerful platform for medical imaging applications (in positron emission tomography/computed tomography and in positron emission tomography/magnetic resonance), for X-ray quality control as well as for novel compact radiation protection instruments. This article gives an overview of SiPMs for medical imaging and dosimetry. In addition, a learning and training program targeted to graduate students is described. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Investigation of Self Triggered Cosmic Ray Detectors using Silicon Photomultiplier

    Science.gov (United States)

    Knox, Adrian; Niduaza, Rommel; Hernandez, Victor; Ruiz, Daniel; Ramos, Daniel; Fan, Sewan; Fatuzzo, Laura; Ritt, Stefan

    2015-04-01

    The silicon photomultiplier (SiPM) is a highly sensitive light detector capable of measuring single photons. It costs a fraction of the photomultiplier tube and operates slightly above the breakdown voltage. At this conference we describe our investigation of SiPM, the multipixel photon counters (MPPC) from Hamamatsu as readout detectors for plastic scintillators working for detecting cosmic ray particles. Our setup consists of scintillator sheets embedded with blue to green wavelength shifting fibers optically coupled to MPPCs to detect scintillating light. Four detector assemblies would be constructed and arranged to work in self triggered mode. Using custom matching tee boxes, the amplified MPPC signals are fed to discriminators with threshold set to give a reasonable coincidence count rate. Moreover, the detector waveforms are digitized using a 5 Giga Samples per second waveform digitizer, the DRS4, and triggered with the coincidence logic to capture the MPPC waveforms. Offline analysis of the digitized waveforms is accomplished using the CERN package PAW and results of our experiments and the data analysis would also be discussed. US Department of Education Title V Grant Number PO31S090007.

  6. A Prototype RICH Detector Using Multi-Anode Photo Multiplier Tubes and Hybrid Photo-Diodes

    CERN Document Server

    Albrecht, E; Bibby, J H; Brook, N H; Doucas, G; Duane, A; Easo, S; Eklund, L; French, M; Gibson, V; Gys, Thierry; Halley, A W; Harnew, N; John, M; Piedigrossi, D; Rademacker, J; Simmons, B; Smale, N J; Teixeira-Dias, P; Toudup, L W; Websdale, David M; Wilkinson, G R; Wotton, S A

    2001-01-01

    The performance of a prototype Ring Imaging Cherenkov Detector is studied using a charged particle beam. The detector performance, using CF4 and air as radiators, is described. Cherenkov angle precision and photoelectron yield using hybrid photo-diodes and multi-anode PMTs agree with simulations and are assessed in terms of the requirements of the LHCb experiment.

  7. Calibration and Characterization of the IceCube Photomultiplier Tube

    Energy Technology Data Exchange (ETDEWEB)

    IceCube Collaboration; Abbasi, R.; al., et

    2010-02-11

    Over 5,000 PMTs are being deployed at the South Pole to compose the IceCube neutrino observatory. Many are placed deep in the ice to detect Cherenkov light emitted by the products of high-energy neutrino interactions, and others are frozen into tanks on the surface to detect particles from atmospheric cosmic ray showers. IceCube is using the 10-inch diameter R7081-02 made by Hamamatsu Photonics. This paper describes the laboratory characterization and calibration of these PMTs before deployment. PMTs were illuminated with pulses ranging from single photons to saturation level. Parameterizations are given for the single photoelectron charge spectrum and the saturation behavior. Time resolution, late pulses and afterpulses are characterized. Because the PMTs are relatively large, the cathode sensitivity uniformity was measured. The absolute photon detection efficiency was calibrated using Rayleigh-scattered photons from a nitrogen laser. Measured characteristics are discussed in the context of their relevance to IceCube event reconstruction and simulation efforts.

  8. Calibration and characterization of the IceCube photomultiplier tube

    Science.gov (United States)

    Abbasi, R.; Abdou, Y.; Abu-Zayyad, T.; Adams, J.; Aguilar, J. A.; Ahlers, M.; Andeen, K.; Auffenberg, J.; Bai, X.; Baker, M.; Barwick, S. W.; Bay, R.; Bazo Alba, J. L.; Beattie, K.; Beatty, J. J.; Bechet, S.; Becker, J. K.; Becker, K.-H.; Benabderrahmane, M. L.; Berdermann, J.; Berghaus, P.; Berley, D.; Bernardini, E.; Bertrand, D.; Besson, D. Z.; Bissok, M.; Blaufuss, E.; Boersma, D. J.; Bohm, C.; Botner, O.; Bradley, L.; Braun, J.; Buitink, S.; Carson, M.; Chirkin, D.; Christy, B.; Clem, J.; Cohen, S.; Colnard, C.; Cowen, D. F.; D'Agostino, M. V.; Danninger, M.; de Clercq, C.; Demirörs, L.; Depaepe, O.; Descamps, F.; Desiati, P.; de Vries-Uiterweerd, G.; Deyoung, T.; Díaz-Vélez, J. C.; Dreyer, J.; Dumm, J. P.; Duvoort, M. R.; Ehrlich, R.; Eisch, J.; Ellsworth, R. W.; Engdegård, O.; Euler, S.; Evenson, P. A.; Fadiran, O.; Fazely, A. R.; Feusels, T.; Filimonov, K.; Finley, C.; Foerster, M. M.; Fox, B. D.; Franckowiak, A.; Franke, R.; Gaisser, T. K.; Gallagher, J.; Ganugapati, R.; Geisler, M.; Gerhardt, L.; Gladstone, L.; Goldschmidt, A.; Goodman, J. A.; Grant, D.; Griesel, T.; Groß, A.; Grullon, S.; Gunasingha, R. M.; Gurtner, M.; Ha, C.; Hallgren, A.; Halzen, F.; Han, K.; Hanson, K.; Hasegawa, Y.; Haugen, J.; Helbing, K.; Herquet, P.; Hickford, S.; Hill, G. C.; Hoffman, K. D.; Homeier, A.; Hoshina, K.; Hubert, D.; Huelsnitz, W.; Hülß, J.-P.; Hulth, P. O.; Hultqvist, K.; Hussain, S.; Imlay, R. L.; Inaba, M.; Ishihara, A.; Jacobsen, J.; Japaridze, G. S.; Johansson, H.; Joseph, J. M.; Kampert, K.-H.; Kappes, A.; Karg, T.; Karle, A.; Kelley, J. L.; Kemming, N.; Kenny, P.; Kiryluk, J.; Kislat, F.; Kitamura, N.; Klein, S. R.; Knops, S.; Kohnen, G.; Kolanoski, H.; Köpke, L.; Koskinen, D. J.; Kowalski, M.; Kowarik, T.; Krasberg, M.; Krings, T.; Kroll, G.; Kuehn, K.; Kuwabara, T.; Labare, M.; Lafebre, S.; Laihem, K.; Landsman, H.; Lauer, R.; Laundrie, A.; Lehmann, R.; Lennarz, D.; Lünemann, J.; Madsen, J.; Majumdar, P.; Maruyama, R.; Mase, K.; Matis, H. S.; Matusik, M.; Meagher, K.; Merck, M.; Mészáros, P.; Meures, T.; Middell, E.; Milke, N.; Miyamoto, H.; Montaruli, T.; Morse, R.; Movit, S. M.; Nahnhauer, R.; Nam, J. W.; Naumann, U.; Nießen, P.; Nygren, D. R.; Odrowski, S.; Olivas, A.; Olivo, M.; Ono, M.; Panknin, S.; Paul, L.; Pérez de Los Heros, C.; Petrovic, J.; Piegsa, A.; Pieloth, D.; Pohl, A. C.; Porrata, R.; Posselt, J.; Price, P. B.; Prikockis, M.; Przybylski, G. T.; Rawlins, K.; Redl, P.; Resconi, E.; Rhode, W.; Ribordy, M.; Rizzo, A.; Robl, P.; Rodrigues, J. P.; Roth, P.; Rothmaier, F.; Rott, C.; Roucelle, C.; Rutledge, D.; Ruzybayev, B.; Ryckbosch, D.; Sander, H.-G.; Sandstrom, P.; Sarkar, S.; Schatto, K.; Schlenstedt, S.; Schmidt, T.; Schneider, D.; Schukraft, A.; Schultes, A.; Schulz, O.; Schunck, M.; Seckel, D.; Semburg, B.; Seo, S. H.; Sestayo, Y.; Seunarine, S.; Silvestri, A.; Slipak, A.; Spiczak, G. M.; Spiering, C.; Stamatikos, M.; Stanev, T.; Stephens, G.; Stezelberger, T.; Stokstad, R. G.; Stoyanov, S.; Strahler, E. A.; Straszheim, T.; Sullivan, G. W.; Swillens, Q.; Taboada, I.; Tamburro, A.; Tarasova, O.; Tepe, A.; Ter-Antonyan, S.; Terranova, C.; Tilav, S.; Toale, P. A.; Tosi, D.; Turčan, D.; van Eijndhoven, N.; Vandenbroucke, J.; van Overloop, A.; van Santen, J.; Voigt, B.; Wahl, D.; Walck, C.; Waldenmaier, T.; Wallraff, M.; Walter, M.; Wendt, C.; Westerhoff, S.; Whitehorn, N.; Wiebe, K.; Wiebusch, C. H.; Wikström, G.; Williams, D. R.; Wischnewski, R.; Wissing, H.; Woschnagg, K.; Xu, C.; Xu, X. W.; Yodh, G.; Yoshida, S.; Zarzhitsky, P.; IceCube Collaboration

    2010-06-01

    Over 5000 PMTs are being deployed at the South Pole to compose the IceCube neutrino observatory. Many are placed deep in the ice to detect Cherenkov light emitted by the products of high-energy neutrino interactions, and others are frozen into tanks on the surface to detect particles from atmospheric cosmic ray showers. IceCube is using the 10-in. diameter R7081-02 made by Hamamatsu Photonics. This paper describes the laboratory characterization and calibration of these PMTs before deployment. PMTs were illuminated with pulses ranging from single photons to saturation level. Parameterizations are given for the single photoelectron charge spectrum and the saturation behavior. Time resolution, late pulses and afterpulses are characterized. Because the PMTs are relatively large, the cathode sensitivity uniformity was measured. The absolute photon detection efficiency was calibrated using Rayleigh-scattered photons from a nitrogen laser. Measured characteristics are discussed in the context of their relevance to IceCube event reconstruction and simulation efforts.

  9. Suppressing ringing caused by large photomultiplier tube signals

    Institute of Scientific and Technical Information of China (English)

    JIANG Wen-Qi; GU Shu-Di; John Joseph; LIU Da-Wei; Kam-Biu Luk; Herbert Steiner; WANG Zheng; WU Qun

    2012-01-01

    We describe here the characteristic features of the ringing we observed following large PMT signalsin the Daya Bay reactor antineutrino experiment.We conclude that the ceramic capacitors used in the circuitryof the PMT bases and the HV-signal decouplers are the primary cause for this ringing.We present some possibleschemes to reduce the ringing when replacing these ceramic capacitors is not feasible.

  10. Calibration and Characterization of the IceCube Photomultiplier Tube

    CERN Document Server

    Abbasi, R; Abu-Zayyad, T; Adams, J; Aguilar, J A; Ahlers, M; Andeen, K; Auffenberg, J; Bai, X; Baker, M; Barwick, S W; Bay, R; Alba, J L Bazo; Beattie, K; Beatty, J J; Bechet, S; Becker, J K; Becker, K -H; Benabderrahmane, M L; Berdermann, J; Berghaus, P; Berley, D; Bernardini, E; Bertrand, D; Besson, D Z; Bissok, M; Blaufuss, E; Boersma, D J; Bohm, C; Botner, O; Bradley, L; Braun, J; Buitink, S; Carson, M; Chirkin, D; Christy, B; Clem, J; Cohen, S; Colnard, C; Cowen, D F; D'Agostino, M V; Danninger, M; De Clercq, C; Demirörs, L; Depaepe, O; Descamps, F; Desiati, P; de Vries-Uiterweerd, G; DeYoung, T; Díaz-Vélez, J C; Dreyer, J; Dumm, J P; Duvoort, M R; Ehrlich, R; Eisch, J; Ellsworth, R W; Engdegård, O; Euler, S; Evenson, P A; Fadiran, O; Fazely, A R; Feusels, T; Filimonov, K; Finley, C; Foerster, M M; Fox, B D; Franckowiak, A; Franke, R; Gaisser, T K; Gallagher, J; Ganugapati, R; Geisler, M; Gerhardt, L; Gladstone, L; Goldschmidt, A; Goodman, J A; Grant, D; Griesel, T; Groß, A; Grullon, S; Gunasingha, R M; Gurtner, M; Ha, C; Hallgren, A; Halzen, F; Han, K; Hanson, K; Hasegawa, Y; Haugen, J; Helbing, K; Herquet, P; Hickford, S; Hill, G C; Hoffman, K D; Homeier, A; Hoshina, K; Hubert, D; Huelsnitz, W; Hülß, J -P; Hulth, P O; Hultqvist, K; Hussain, S; Imlay, R L; Inaba, M; Ishihara, A; Jacobsen, J; Japaridze, G S; Johansson, H; Joseph, J M; Kampert, K -H; Kappes, A; Karg, T; Karle, A; Kelley, J L; Kemming, N; Kenny, P; Kiryluk, J; Kislat, F; Kitamura, N; Klein, S R; Knops, S; Kohnen, G; Kolanoski, H; Köpke, L; Koskinen, D J; Kowalski, M; Kowarik, T; Krasberg, M; Krings, T; Kroll, G; Kuehn, K; Kuwabara, T; Labare, M; Lafebre, S; Laihem, K; Landsman, H; Lauer, R; Laundrie, A; Lehmann, R; Lennarz, D; Lünemann, J; Madsen, J; Majumdar, P; Maruyama, R; Mase, K; Matis, H S; Matusik, M; Meagher, K; Merck, M; Mészáros, P; Meures, T; Middell, E; Milke, N; Miyamoto, H; Montaruli, T; Morse, R; Movit, S M; Nahnhauer, R; Nam, J W; Naumann, U; Nießen, P; Nygren, D R; Odrowski, S; Olivas, A; Olivo, M; Ono, M; Panknin, S; Paul, L; Heros, C Pérez de los; Petrovic, J; Piegsa, A; Pieloth, D; Pohl, A C; Porrata, R; Posselt, J; Price, P B; Prikockis, M; Przybylski, G T; Rawlins, K; Redl, P; Resconi, E; Rhode, W; Ribordy, M; Rizzo, A; Robl, P; Rodrigues, J P; Roth, P; Rothmaier, F; Rott, C; Roucelle, C; Rutledge, D; Ruzybayev, B; Ryckbosch, D; Sander, H -G; Sandstrom, P; Sarkar, S; Schatto, K; Schlenstedt, S; Schmidt, T; Schneider, D; Schukraft, A; Schultes, A; Schulz, O; Schunck, M; Seckel, D; Semburg, B; Seo, S H; Sestayo, Y; Seunarine, S; Silvestri, A; Slipak, A; Spiczak, G M; Spiering, C; Stamatikos, M; Stanev, T; Stephens, G; Stezelberger, T; Stokstad, R G; Stoyanov, S; Strahler, E A; Straszheim, T; Sullivan, G W; Swillens, Q; Taboada, I; Tamburro, A; Tarasova, O; Tepe, A; Ter-Antonyan, S; Terranova, C; Tilav, S; Toale, P A; Tosi, D; Turcan, D; van Eijndhoven, N; Vandenbroucke, J; Van Overloop, A; van Santen, J; Voigt, B; Wahl, D; Walck, C; Waldenmaier, T; Wallraff, M; Walter, M; Wendt, C; Westerhoff, S; Whitehorn, N; Wiebe, K; Wiebusch, C H; Wikström, G; Williams, D R; Wischnewski, R; Wissing, H; Woschnagg, K; Xu, C; Xu, X W; Yodh, G; Yoshida, S; Zarzhitsky, P

    2010-01-01

    Over 5,000 PMTs are being deployed at the South Pole to compose the IceCube neutrino observatory. Many are placed deep in the ice to detect Cherenkov light emitted by the products of high-energy neutrino interactions, and others are frozen into tanks on the surface to detect particles from atmospheric cosmic ray showers. IceCube is using the 10-inch diameter R7081-02 made by Hamamatsu Photonics. This paper describes the laboratory characterization and calibration of these PMTs before deployment. PMTs were illuminated with pulses ranging from single photons to saturation level. Parameterizations are given for the single photoelectron charge spectrum and the saturation behavior. Time resolution, late pulses and afterpulses are characterized. Because the PMTs are relatively large, the cathode sensitivity uniformity was measured. The absolute photon detection efficiency was calibrated using Rayleigh-scattered photons from a nitrogen laser. Measured characteristics are discussed in the context of their relevance t...

  11. A concise quantum efficiency measurement system for gaseous photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Moriya, Toru [Department of Physics, Yamagata University, Yamagata 990-8560 (Japan); Tokanai, Fuyuki, E-mail: tokanai@sci.kj.yamagata-u.ac.jp [Department of Physics, Yamagata University, Yamagata 990-8560 (Japan); Okazaki, Keisuke; Sakurai, Hirohisa; Gunji, Shuichi [Department of Physics, Yamagata University, Yamagata 990-8560 (Japan); Kawabata, Hironobu; Sohtome, Takayuki [BUNKOUKEIKI Co., Ltd., Hachioji, Tokyo 192-0033 (Japan); Sumiyoshi, Takayuki [Graduate School of the Faculty of Science and Engineering, Tokyo Metropolitan University, Tokyo 192-0397 (Japan); Sugiyama, Hirioyuki; Okada, Teruyuki; Ohishi, Noboru [Electron Tube Division, Hamamatsu Photonics K.K., Shizuoka 438-0193 (Japan); Kishimoto, Syunji [Institute of Material Structure Science, KEK, Tsukuba 305-0801 (Japan)

    2013-12-21

    We have been developing gaseous photomultiplier tubes (PMTs) with a bialkali photocathode combined with micropattern gas detectors (MPGDs). The sensitivity of a PMT is described in terms of its quantum efficiency (QE). The QE is very important in many experiments, particularly when dealing with low photon statistics. A concise QE measurement system has been developed to evaluate the characteristics of a sealed gaseous PMT with a bialkali photocathode. This QE measurement system consists of a Xe arc lamp source, reflective optics and filters, a monochromator, and a reference Si photodiode detector. Using the system, we evaluated the QE, gain, and long-term stability of the gaseous PMT. Here, we report the results of our evaluation.

  12. Performances of multi-channel ceramic photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Comby, G.; Karolak, M.; Piret, Y.; Mouly, J.P. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee; Kuzmin, E. [Joint Inst. for Nuclear Research, Dubna (Russian Federation)

    1995-09-01

    Ceramic electron multipliers with real metal dynodes and independent channels ware constructed using multilayer ceramic technology. Tests of these prototypes show their capability to form sensitive detectors such as photomultipliers or light intensifiers. Here, we present results for the photocathode sensitivity, dynode activation, gain, linearity range and dynamic characteristics as well as the effect of 3-year aging of the main operational functions. The advantages provided by the ceramic components are discussed. These results motivate the development of a compact 256 pixel ceramic photomultiplier. (author).

  13. Light Pulses to Photomultipliers from Extended Scintillators

    CERN Document Server

    Boemi, D; CERN. Geneva; Costa, S; Insolia, A; Panebianco, S; Potenza, R; Randazzo, N; Reito, S; Romanski, J; Russo, G V; Tuvé, C

    1994-01-01

    Light pulses received by photomultipliers coupled to scintillators are investigated in the cases of long scintillator slats or rods as well as large disc-shaped ones and compared with pulses from point-like scintillators. Results of experimental tests for the disc-shaped configuration performed with the single photon counting technique are presented and compared with numerical calculations. The calculations were done describing light pulse shape by means of a quite new general analytical method based on virtual light paths and images from geometrical optics. The associated electric pulses from the photomultipliers are then discussed and their dependence from source-photocathode distance are put in light.

  14. Pulsed-source time-resolved phosphorimetry: comparison of a commercial gated photomultiplier with a specially wired ungated photomultiplier.

    Science.gov (United States)

    Persvik, Øyvind; Melø, Thor Bernt; Naqvi, K Razi

    2013-06-01

    A common problem encountered in recording delayed light emission is that the signal of interest is preceded by a much more intense signal arising from prompt fluorescence. When a photomultiplier tube (PMT) is used as the photosensor in a pulsed-source phosphorimeter, two options are open to an experimenter who finds mechanical shutters inconvenient or impracticable and photon counting inappropriate: apply an electronic gate that suppresses the PMT gain for a brief period, or use a wiring scheme that enables the PMT to quickly regain normal operation after an intense burst of prompt emission. The performance of a squirrel-cage PMT that operates in the latter mode is compared with a new gateable PMT (Hamamatsu H11526 series) with a minimum gate time of 100 ns. The two detectors are found to provide practically the same temporal record of the delayed emission, but the ungated PMT is slightly superior in terms of recovery time and signal-to-noise ratio.

  15. Practical Time Mark Estimators for Multichannel Digital Silicon Photomultipliers

    NARCIS (Netherlands)

    Venialgo, E.; Mandai, S.; Gong, T.; Schaart, D.R.; Charbon, E.

    2015-01-01

    Multiple time-to-digital converters coupled with silicon photomultipliers allow to timestamp several light photons generated by a scintillation event. Multichannel digital silicon photomultipliers opened the possibility to estimate a gammaphoton time mark by using several photoelectrons timestamps.

  16. VUV-sensitive silicon-photomultipliers for the nEXO-experiment

    Energy Technology Data Exchange (ETDEWEB)

    Wrede, Gerrit; Bayerlein, Reimund; Hufschmidt, Patrick; Jamil, Ako; Schneider, Judith; Wagenpfeil, Michael; Ziegler, Tobias; Hoessl, Juergen; Anton, Gisela; Michel, Thilo [ECAP, Friedrich-Alexander-Universitaet Erlangen-Nuernberg (Germany)

    2016-07-01

    The nEXO (next Enriched Xenon Observatory) experiment will search for the neutrinoless double beta decay of Xe-136 with a liquid xenon TPC (Time ProjectionChamber). The sensitivity of the experiment is related to the energy resolution, which itself depends on the accuracies of the measurements of the amount of drifting electrons and the number of scintillation photons with their wavelength being in the vacuum ultraviolet band. Silicon Photomultipliers (SiPM) shall be used for the detection of the scintillation light, since they can be produced extremely radiopure. Commercially available SiPM do not fulfill all requirements of the nEXO experiment, thus a dedicated development is necessary. To characterize the silicon photomultipliers, we have built a test apparatus for xenon liquefaction, in which a VUV-sensitive photomultiplier tube can be operated together with the SiPM. In this contribution we present our apparatus for the SiPM characterization measurements and our latest results on the test of the silicon photomultipliers for the detection of xenon scintillation light.

  17. New photomultiplier active base for Hall C Jefferson Lab lead tungstate calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Popov, Vladimir E. [JLAB; Mkrtchyan, Hamlet G. [Artem Alikhanian National Laboratory

    2012-11-01

    A new photomultiplier tube active base was designed and tested. The base combines active voltage division circuit and fast amplifier, powered by the current flowing through voltage divider. This base is developed to upgrade older photomultiplier bases of Jefferson Lab lead-tungsten calorimeter (about ˜1200 crystals of PbWO{sub 4} from the PrimEx experimental setup). This is needed for the extension of detectors' rate capability to meet requirements of new Hall C proposal PR12-11-102 of measurements of the L/T separated cross sections and their ratio R = πL/πT in neutral-pion p(e,e'π0)p deep exclusive and p(p(e,e'π{sup 0})p)X semi-inclusive scattering regions. New active base is direct replacement of older passive base circuit without adding of additional power or signal lines. However, it extends detectors rate capability with factor over 20. Moreover, transistorized voltage divider improves detector's amplitude resolution due to reduction of photomultiplier gain dependence from tube anode current. The PMT active base is the invention disclosed in V. Popov's U.S. Patent No. 6,791,269, which successfully works over ten years in several Jefferson Lab Cherenkov detectors. The following design is a new revised and improved electronic circuit with better gain stability and linearity in challenge to meet requirements of new Hall C experimental setup. New active base performance was tested using fast LED light source and Pr:LuAG scintillator and gamma sources. Electronics radiation hardness was tested on JLab accelerator. Results of testing R4125 Hamamatsu photomultiplier tube in new active base are presented.

  18. Tube-graft-Sheet Nano-Objects Created by A Stepwise Self-Assembly of Polymer-Polyoxometalate Hybrids.

    Science.gov (United States)

    Tang, Jing; Li, Xue-Ying; Wu, Han; Ren, Li-Jun; Zhang, Yu-Qi; Yao, Hai-Xia; Hu, Min-Biao; Wang, Wei

    2016-01-19

    In this work, we report the preparation of complex nano-objects by means of a stepwise self-assembly of two polymer-polyoxometalate hybrids (PPHs) in solution. The PPHs are designed and synthesized by tethering two linear poly(ε-caprolactone)s (PCL) of different molecular weights (MW) on a complex of a Wells-Dawson-type polyoxometalate (POM) cluster and its countraions. The higher MW PCL-POM self-assembled into nanosheets, while the lower MW PCL-POM assembled into nanotubes just by altering the ratio of water in the DMF-water mixed solvent system. The two nano-objects have a similar membrane structure in which a PCL layer is sandwiched by the two POM-based complex layers. The PCL layer in the nanosheets is semicrystalline, while the PCL layer in the nanotubes is amorphous. We further exploited this MW-dependence to self-assemble the nanotubes on the nanosheet edges to create complex tube-graft-sheet nano-objects. We found that the nanotubes nucleate on the four {110} faces of the PCL crystal and then further grow along the crystallographic b-axis of the PCL crystal. Our findings offer hope for the further development of nano-objects with increasing complexity.

  19. Status of the Silicon Photomultiplier Telescope FAMOUS for the Fluorescence Detection of UHECRs

    CERN Document Server

    Niggemann, Tim; Brogueira, Pedro; Bueno, Antonio; Eichler, Hans Michael; Ferreira, Miguel; Hebbeker, Thomas; Lauscher, Markus; Mendes, Luís; Middendorf, Lukas; Navas, Sergio; Peters, Christine; Pimenta, Mário; Ruiz, Angel; Schumacher, Johannes; Stephan, Maurice

    2015-01-01

    An established technique for the measurement of ultra-high-energy-cosmic-rays is the detection of the fluorescence light induced in the atmosphere of the Earth, by means of telescopes equipped with photomultiplier tubes. Silicon photomultipliers (SiPMs) promise an increase in the photon detection efficiency which outperforms conventional photomultiplier tubes. In combination with their compact package, a moderate bias voltage of several ten volt and single photon resolution, the use of SiPMs can improve the energy and spatial resolution of air fluorescence measurements, and lead to a gain in information on the primary particle. Though, drawbacks like a high dark-noise-rate and a strong temperature dependency have to be managed. FAMOUS is a refracting telescope prototype instrumented with 64 SiPMs of which the main optical element is a Fresnel lens of 549.7 mm diameter and 502.1 mm focal length. The sensitive area of the SiPMs is increased by a special light collection system consisting of Winston cones. The t...

  20. A new detector concept for silicon photomultipliers

    Science.gov (United States)

    Sadigov, A.; Ahmadov, F.; Ahmadov, G.; Ariffin, A.; Khorev, S.; Sadygov, Z.; Suleymanov, S.; Zerrouk, F.; Madatov, R.

    2016-07-01

    A new design and principle of operation of silicon photomultipliers are presented. The new design comprises a semiconductor substrate and an array of independent micro-phototransistors formed on the substrate. Each micro-phototransistor comprises a photosensitive base operating in Geiger mode and an individual micro-emitter covering a small part of the base layer, thereby creating, together with this latter, a micro-transistor. Both micro-emitters and photosensitive base layers are connected with two respective independent metal grids via their individual micro-resistors. The total value of signal gain in the proposed silicon photomultiplier is a result of both the avalanche gain in the base layer and the corresponding gain in the micro-transistor. The main goals of the new design are: significantly lower both optical crosstalk and after-pulse effects at high signal amplification, improve speed of single photoelectron pulse formation, and significantly reduce the device capacitance.

  1. A new detector concept for silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Sadigov, A., E-mail: saazik@yandex.ru [National Nuclear Research Center, Baku (Azerbaijan); Ahmadov, F.; Ahmadov, G. [National Nuclear Research Center, Baku (Azerbaijan); Ariffin, A.; Khorev, S. [Zecotek Photonics Inc., Vancouver (Canada); Sadygov, Z. [National Nuclear Research Center, Baku (Azerbaijan); Joint Institute for Nuclear Research, Dubna (Russian Federation); Suleymanov, S. [National Nuclear Research Center, Baku (Azerbaijan); Zerrouk, F. [Zecotek Photonics Inc., Vancouver (Canada); Madatov, R. [Institute of Radiation Problems, Baku (Azerbaijan)

    2016-07-11

    A new design and principle of operation of silicon photomultipliers are presented. The new design comprises a semiconductor substrate and an array of independent micro-phototransistors formed on the substrate. Each micro-phototransistor comprises a photosensitive base operating in Geiger mode and an individual micro-emitter covering a small part of the base layer, thereby creating, together with this latter, a micro-transistor. Both micro-emitters and photosensitive base layers are connected with two respective independent metal grids via their individual micro-resistors. The total value of signal gain in the proposed silicon photomultiplier is a result of both the avalanche gain in the base layer and the corresponding gain in the micro-transistor. The main goals of the new design are: significantly lower both optical crosstalk and after-pulse effects at high signal amplification, improve speed of single photoelectron pulse formation, and significantly reduce the device capacitance.

  2. Cherenkov TOF PET with silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Dolenec, R., E-mail: rok.dolenec@ijs.si [Faculty of Chemistry and Chemical Engineering, University of Maribor, Maribor (Slovenia); Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana (Slovenia); Korpar, S. [Faculty of Chemistry and Chemical Engineering, University of Maribor, Maribor (Slovenia); Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Križan, P. [Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana (Slovenia); Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia); Pestotnik, R. [Jožef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana (Slovenia)

    2015-12-21

    As previously demonstrated, an excellent timing resolution below 100 ps FWHM is possible in time-of-flight positron emission tomography (TOF PET) if the detection method is based on the principle of detecting photons of Cherenkov light, produced in a suitable material and detected by microchannel plate photomultipliers (MCP PMTs). In this work, the silicon photomultipliers (SiPMs) were tested for the first time as the photodetectors in Cherenkov TOF PET. The high photon detection efficiency (PDE) of SiPMs led to a large improvement in detection efficiency. On the other hand, the time response of currently available SiPMs is not as good as that of MCP PMTs. The SiPM dark counts introduce a new source of random coincidences in Cherenkov method, which would be overwhelming with present SiPM technology at room temperature. When the apparatus was cooled, its performance significantly improved.

  3. Timing tests of silicon-photomultipliers for readout of large plastic scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Gohl, Stefan; Cowan, Thomas E.; Roeder, Marko [Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Germany); TU Dresden (Germany); Bemmerer, Daniel; Heidel, Klaus; Stach, Daniel; Wagner, Andreas; Weinberger, David [Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Germany); Reinhardt, Tobias [TU Dresden (Germany); Helmholtz-Zentrum Dresden-Rossendorf (HZDR) (Germany); Collaboration: R3B-Collaboration

    2014-07-01

    Silicon Photomultipliers (SiPMs) are under study as a possible replacement for timing photomultiplier tubes (PMTs) in the NeuLAND (New Large Area Neutron Detector) detector at FAIR. SiPMs have several advantages over PMTs. They are insensitive to magnetic fields, small and they can be manufactured economically. Therefore, studies have been made with different SiPMs, preamplifiers and scintillators aiming to find a suitable setup with a good timing resolution for NeuLAND. Some parameters, e.g. bias voltage and light input, were tuned as well. The SiPMs were irradiated with an electron beam at ELBE and a picosecond laser system while the signals were recorded with a digital oscilloscope and evaluated by using a software Constant Fraction Discriminator (CFD). Preliminary results are presented.

  4. SiMPl - High efficient silicon photomultipliers with integrated bulk resistor

    Energy Technology Data Exchange (ETDEWEB)

    Jendrysik, Christian; Andricek, Ladislav; Liemann, Gerhard; Moser, Hans-Guenther; Ninkovic, Jelena; Richter, Rainer [Max-Planck-Institute for Physics, Semiconductor Laboratory, Munich (Germany); Lutz, Gerhard [PN Sensor GmbH, Munich (Germany)

    2010-07-01

    Silicon photomultipliers (SiPM) are avalanche photodetectors which tend to replace conventional photomultiplier tubes in many application areas where detectors with high photon detection efficiency (PDE) are in the focus of interest. For Geiger mode operation high ohmic polysilicon is needed as quench resistor. On the one hand this forms a barrier for incident light, thus decreasing the PDE, which is a crucial point at low light levels. On the other hand it's also the most cost driving technological issue in fabrication. We present a novel design for a high efficient SiPM with the quench resistors integrated into the silicon bulk. Therefore obstacles for light like metal lines or contacts within the active area can be omitted and the fill factor of the device is only limited by the gaps necessary for optical crosstalk suppression. First results of this novel light detector are presented.

  5. An integrated closed-tube 2-plex PCR amplification and hybridization assay with switchable lanthanide luminescence based spatial detection.

    Science.gov (United States)

    Lahdenperä, Susanne; Spangar, Anni; Lempainen, Anna-Maija; Joki, Laura; Soukka, Tero

    2015-06-21

    Switchable lanthanide luminescence is a binary probe technology that inherently enables a high signal modulation in separation-free detection of DNA targets. A luminescent lanthanide complex is formed only when the two probes hybridize adjacently to their target DNA. We have now further adapted this technology for the first time in the integration of a 2-plex polymerase chain reaction (PCR) amplification and hybridization-based solid-phase detection of the amplification products of the Staphylococcus aureus gyrB gene and an internal amplification control (IAC). The assay was performed in a sealed polypropylene PCR chip containing a flat-bottom reaction chamber with two immobilized capture probe spots. The surface of the reaction chamber was functionalized with NHS-PEG-azide and alkyne-modified capture probes for each amplicon, labeled with a light harvesting antenna ligand, and covalently attached as spots to the azide-modified reaction chamber using a copper(i)-catalyzed azide-alkyne cycloaddition. Asymmetric duplex-PCR was then performed with no template, one template or both templates present and with a europium ion carrier chelate labeled probe for each amplicon in the reaction. After amplification europium fluorescence was measured by scanning the reaction chamber as a 10 × 10 raster with 0.6 mm resolution in time-resolved mode. With this assay we were able to co-amplify and detect the amplification products of the gyrB target from 100, 1000 and 10,000 copies of isolated S. aureus DNA together with the amplification products from the initial 5000 copies of the synthetic IAC template in the same sealed reaction chamber. The addition of 10,000 copies of isolated non-target Escherichia coli DNA in the same reaction with 5000 copies of the synthetic IAC template did not interfere with the amplification or detection of the IAC. The dynamic range of the assay for the synthetic S. aureus gyrB target was three orders of magnitude and the limit of detection of 8 p

  6. R and D status of a large-aperture hybrid avalanche photo-detector

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Toshinori, E-mail: toshi@hep.phys.s.u-tokyo.ac.j [University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Aihara, Hiroaki; Iwasaki, Masako; Fujimori, Hiroki; Kasimura, Keizo; Mineo, Sogo; Uchida, Tomohisa [University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Tanaka, Manobu [Institute for Particle and Nuclear Studies, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Kawai, Yoshihiko; Kyushima, Hiroyuki; Suyama, Motohiro [Electron Tube Division, Hamamatsu Photonics K.K., 314-5 Shimokanzo, Iwata City, Shizuoka 438-0193 (Japan); Shiozawa, Masato [Kamioka Observatory, Institute for Cosmic Ray Research ICRR, University of Tokyo, Higashi-Mozumi, Kamioka-cho, Hida City, Gifu 506-1205 (Japan)

    2010-11-01

    This paper reports on the R and D status of a large-aperture Hybrid Avalanche Photo-Detector (HAPD). We have developed a 13-inch aperture HAPD and its readout system. The HAPD is a photo-detector expected to replace the photomultiplier tube (PMT) in next-generation imaging water Cherenkov detectors such as Hyper Kamiokande. We will present the recent progress made in readout system development. The readout system involves a fast sampling device. The sampling depth (number of cells) has been extended to 256 from 64 in order to measure longer waveform length. The variation in AC gain is now fixed and the input analog bandwidth improved.

  7. Development of silicon photomultipliers and their applications to GlueX calorimetry

    Science.gov (United States)

    Smith, Elton S.

    2016-07-01

    The GlueX experiment is a photoproduction experiment in Hall D at Jefferson Lab that is being commissioned for use with the new 12 GeV accelerator. The purpose of the experiment is to search for Hybrid mesons, which are mesons with quark and gluon degrees of freedom. The barrel calorimeter of GlueX is instrumented with 4000 large-area (1.2 × 1.2 cm2) silicon photomultipliers (SiPMs). These photon sensors have properties similar to vacuum photomultipliers, but are unaffected by high magnetic fields. In our experiment they operate in magnetic fields exceeding 1T. After extensive tests with a variety of sensors, we chose the S12045(X) custom SiPM arrays manufactured by Hamamatsu Corporation, also known as multi-pixel photon counters (MPPCs). We will give an overview of this new technology as well as the experience gained during two commissioning periods with beam.

  8. Development of silicon photomultipliers and their applications to GlueX calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Elton S., E-mail: elton@jlab.org [Jefferson Lab, Newport News, VA 23606 (United States)

    2016-07-07

    The GlueX experiment is a photoproduction experiment in Hall D at Jefferson Lab that is being commissioned for use with the new 12 GeV accelerator. The purpose of the experiment is to search for Hybrid mesons, which are mesons with quark and gluon degrees of freedom. The barrel calorimeter of GlueX is instrumented with 4000 large-area (1.2 × 1.2 cm{sup 2}) silicon photomultipliers (SiPMs). These photon sensors have properties similar to vacuum photomultipliers, but are unaffected by high magnetic fields. In our experiment they operate in magnetic fields exceeding 1T. After extensive tests with a variety of sensors, we chose the S12045(X) custom SiPM arrays manufactured by Hamamatsu Corporation, also known as multi-pixel photon counters (MPPCs). We will give an overview of this new technology as well as the experience gained during two commissioning periods with beam.

  9. Development of Silicon Photomultipliers and their Applications to GlueX Calorimetry

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Elton S. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-07-01

    The GlueX experiment is a photoproduction experiment in Hall D at Jefferson Lab that is being commissioned for use with the new 12 GeV accelerator. The purpose of the experiment is to search for Hybrid mesons, which are mesons with quark and gluon degrees of freedom. The barrel calorimeter of GlueX is instrumented with 4000 large-area (1.2 x1.2 cm2) silicon photomultipliers (SiPMs). These photon sensors have properties similar to vacuum photomultipliers, but are unaffected by high magnetic fields. In our experiment they operate in magnetic fields exceeding 1T. After extensive tests with a variety of sensors, we chose the S12045(X) custom SiPM arrays manufactured by Hamamatsu Corporation, also known as multi-pixel photon counters (MPPCs). We will give an overview of this new technology as well as the experience gained during two commissioning periods with beam.

  10. Fiber optic dosimeter with silicon photomultipliers

    Science.gov (United States)

    Moutinho, L. M.; Castro, I. F.; Peralta, L.; Abreu, M. C.; Veloso, J. F. C. A.

    2014-08-01

    A small dimension, real-time readout dosimeter is desirable for specific applications in medical physics as for example, dose measurement in prostate brachytherapy. This particular radiotherapy procedure consists in the permanent deposition of low energy, low-dose and low-dose rate small sized radioactive seeds. We developed a scintillating fiber optic based dosimeter suitable for in-vivo, real-time low dose and low dose rate measurements. Due to the low scintillation light produced in the scintillating fiber, a high sensitive and high gain light detector is required. The Silicon Photomultipliers are an interesting option that allowed us to obtain good results in our studies.

  11. Optical test setup for Silicon Photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Heidemann, Carsten; Enzweiler, Tim; Hebbeker, Thomas; Merschmeyer, Markus

    2015-07-01

    Silicon Photomultipliers (SiPMs) are semiconductor-based photon detectors. Their most important properties, gain and photon detection efficiency, are dependent on or influenced by voltage and temperature and need to be characterised for optimal usage of the SiPMs. The test setup has been built for optical and electrical characterisation of SiPMs. The setup provides a temperature-stabilised SiPM mount, an LED-based multi-purpose light source offers continuous and pulsed operation mode for wavelengths from 300 nm to 650 nm. The result is a complete characterisation of the SiPM within a desired range of operation voltage and ambient temperature.

  12. Inorganic-organic hybrid coating material for the online in-tube solid-phase microextraction of monohydroxy polycyclic aromatic hydrocarbons in urine.

    Science.gov (United States)

    Wang, ShuLing; Xu, Hui

    2016-12-01

    An inorganic-organic hybrid nanocomposite (zinc oxide/polypyrrole) that represents a novel kind of coating for in-tube solid-phase microextraction is reported. The composite coating was prepared by a facile electrochemical polymerization strategy on the inner surface of a stainless-steel tube. Based on the coated tube, a novel online in-tube solid-phase microextraction with liquid chromatography and mass spectrometry method was developed and applied for the extraction of three monohydroxy polycyclic aromatic hydrocarbons in human urine. The coating displayed good extraction ability toward monohydroxy polycyclic aromatic hydrocarbons. In addition, long lifespan, excellent stability, and good compression resistance were also obtained for the coating. The experimental conditions affecting the extraction were optimized systematically. Under the optimal conditions, the limits of detection and quantification were in the range of 0.039-0.050 and 0.130-0.167 ng/mL, respectively. Good linearity (0.2-100 ng/mL) was obtained with correlation coefficients larger than 0.9967. The repeatability, expressed as relative standard deviation, ranged between 2.5% and 9.4%. The method offered the advantage of process simplicity, rapidity, automation, and sensitivity in the analysis of human urinary monohydroxy polycyclic aromatic hydrocarbons in two different cities of Hubei province. An acceptable recovery of monohydroxy polycyclic aromatic hydrocarbons (64-122%) represented the additional attractive features of the method in real urine analysis.

  13. Design of a high dynamic range photomultiplier base board for the BGO ECAL of DAMPE

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhiyong; Zhang, Yunlong, E-mail: ylzhang1@mail.ustc.edu.cn; Dong, Jianing; Wen, Sicheng; Feng, Changqing; Wang, Chi; Wei, Yifeng; Wang, Xiaolian; Xu, Zizong; Liu, Shubin

    2015-04-21

    A base board for photomultiplier tube (PMT) with multi-dynode readout has been developed for the BGO electromagnetic calorimeter (ECAL) of the Dark Matter Particle Explorer (DAMPE). In order to cover a high dynamic range of energy measurements, the signals are read out from different sensitive dynodes 2, 5, and 8 (Dy2, Dy5 and Dy8). The performance of this new type of base board is studied with a light-emitting diode (LED) system and cosmic rays. A wide measuring range from 0.5 to 1.0×10{sup 5} MIPs can be achieved using the VA32 readout Application Specific Integrated Circuit (ASIC)

  14. Hybrid Baryons

    CERN Document Server

    Page, P R

    2003-01-01

    We review the status of hybrid baryons. The only known way to study hybrids rigorously is via excited adiabatic potentials. Hybrids can be modelled by both the bag and flux-tube models. The low-lying hybrid baryon is N 1/2^+ with a mass of 1.5-1.8 GeV. Hybrid baryons can be produced in the glue-rich processes of diffractive gamma N and pi N production, Psi decays and p pbar annihilation.

  15. Back-side readout semiconductor photomultiplier

    Science.gov (United States)

    Choong, Woon-Seng; Holland, Stephen E

    2014-05-20

    This disclosure provides systems, methods, and apparatus related to semiconductor photomultipliers. In one aspect, a device includes a p-type semiconductor substrate, the p-type semiconductor substrate having a first side and a second side, the first side of the p-type semiconductor substrate defining a recess, and the second side of the p-type semiconductor substrate being doped with n-type ions. A conductive material is disposed in the recess. A p-type epitaxial layer is disposed on the second side of the p-type semiconductor substrate. The p-type epitaxial layer includes a first region proximate the p-type semiconductor substrate, the first region being implanted with p-type ions at a higher doping level than the p-type epitaxial layer, and a second region disposed on the first region, the second region being doped with p-type ions at a higher doping level than the first region.

  16. Tests of timing properties of silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Ronzhin, A.; Albrow, M.; /Fermilab; Byrum, K.; /Argonne; Demarteau, M.; Los, S.; /Fermilab; May, E.; /Argonne; Ramberg, A.; /Fermilab; Va' vra, J.; /SLAC; Zatserklyaniy, A.; /Puerto Rico U., Mayaguez

    2010-03-01

    Timing measurements of Silicon Photomultipliers (SiPM) [1] and [2] at the picosecond level were performed at Fermilab. The core timing resolution of the electronic measurement technique is approximately 2 ps. The single photoelectron time resolution (SPTR) was measured for the signals coming from the SiPM's. A SPTR of about one hundred picoseconds was obtained for SiPM's illuminated by laser pulses. The dependence of the SPTR on applied bias voltage and on the wavelength of the light was measured. A simple model is proposed to explain the difference in the SPTR for blue and red light. A time of flight system based on the SiPM's, with quartz Cherenkov radiators, was tested in a proton beam at Fermilab. The time resolution obtained is 35 ps per SiPM. Finally, requirements for the SiPM's temperature and bias voltage stability to maintain the time resolution are discussed.

  17. Muon tracking system with Silicon Photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Arneodo, F.; Benabderrahmane, M.L.; Dahal, S. [New York University Abu Dhabi, Abu Dhabi (United Arab Emirates); Di Giovanni, A., E-mail: adriano.digiovanni@nyu.edu [New York University Abu Dhabi, Abu Dhabi (United Arab Emirates); Pazos Clemens, L. [New York University Abu Dhabi, Abu Dhabi (United Arab Emirates); Candela, A.; D' Incecco, M.; Sablone, D. [Gran Sasso National Laboratory of INFN, Assergi (Italy); Franchi, G. [AGE Scientific Srl, Capezzano Pianore (Italy)

    2015-11-01

    We report the characterisation and performance of a low cost muon tracking system consisting of plastic scintillator bars and Silicon Photomultipliers equipped with a customised front-end electronics based on a fast preamplifier network. This system can be used as a detector test bench for astroparticle physics and for educational and outreach purposes. We investigated the device behaviour in self-trigger and coincidence mode, without using LED and pulse generators, showing that with a relatively simple set up a complete characterisation work can be carried out. A high definition oscilloscope, which can easily be found in many university physics or engineering departments, has been used for triggering and data acquisition. Its capabilities have been exploited to discriminate real particles from the background.

  18. Performance of a cluster of multi-anode photomultipliers equipped with lenses for use in a prototype RICH detector

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht, E.; Baker, J.; Barber, G.; Bibby, J.; Calvi, M.; Charles, M.; Duane, A.; Easo, S.; Eisenhardt, S.; Eklund, L.; French, M.; Gibson, V.; Halley, A.; Halsall, R.; Harnew, N.; John, M.J.J.; Katvars, S.G.; Libby, J. E-mail: jim.libby@cern.ch; Muheim, F.; Paganoni, M.; Petrolini, A.; Playfer, S.; Price, D.; Rademacker, J.; Smale, N.; Topp-Jorgenson, S.; Websdale, D.; Wilkinson, G.; Wotton, S.A

    2002-08-01

    A cluster of multi-anode photomultiplier tubes (MaPMTs) equipped with focusing lenses in front of the tubes was tested in a prototype ring imaging Cherenkov (RICH) detector in a charged particle beam. The readout electronics were capable of capturing the data at 40 MHz. The effects due to charged particles and magnetic field on the MaPMT performance were also studied. The results are used to evaluate the MaPMT as a possible photodetector for the LHCb RICH detectors.

  19. Performance of a cluster of Multi-anode Photomultipliers equipped with lenses for use in a prototype RICH detector

    CERN Document Server

    Albrecht, E; Barber, G J; Bibby, J; Calvi, M; Charles, M J; Duane, A; Easo, S; Eisenhardt, S; Eklund, L; French, M; Gibson, V; Halley, A; Halsall, R; Harnew, N; John, M J J; Katvars, S G; Libby, J; Muheim, F; Paganoni, M; Petrolini, A; Playfer, S; Price, D; Rademacker, J; Smale, N J; Topp-Jørgensen, S; Websdale, David M; Wilkinson, G R; Wooton, S A

    2002-01-01

    A cluster of Multi--anode Photomultiplier Tubes (MaPMTs) equipped with focusing lenses in front of the tubes was tested in a prototype Ring Imaging \\v{C}erenkov detector in a charged particle beam. The readout electronics were capable of capturing the data at 40~MHz. The effects due to charged particles and magnetic field on the MaPMT performance were also studied. The results are used to evaluate the MaPMT as a possible photodetector for the LHCb RICH detectors.

  20. Development of a large area microstructure photomultiplier assembly (LAMPA)

    Science.gov (United States)

    Clifford, E. T. H.; Dick, M.; Facina, M.; Wakeford, D.; Andrews, H. R.; Ing, H.; Best, D.; Baginski, M. J.

    2017-05-01

    Large area (> m2) position-sensitive readout of scintillators is important for passive/active gamma and neutron imaging for counter-terrorism applications. The goal of the LAMPA project is to provide a novel, affordable, large-area photodetector (8" x 8") by replacing the conventional dynodes of photomultiplier tubes (PMTs) with electron multiplier microstructure boards (MSBs) that can be produced using industrial manufacturing techniques. The square, planar format of the LAMPA assemblies enables tiling of multiple units to support large area applications. The LAMPA performance objectives include comparable gain, noise, timing, and energy resolution relative to conventional PMTs, as well as spatial resolution in the few mm range. The current LAMPA prototype is a stack of 8" x 8" MSBs made commercially by chemical etching of a molybdenum substrate and coated with hydrogen-terminated boron-doped diamond for high secondary emission yield (SEY). The layers of MSBs are electrically isolated using ceramic standoffs. Field-shaping grids are located between adjacent boards to achieve good transmission of electrons from one board to the next. The spacing between layers and the design of the microstructure pattern and grids were guided by simulations performed using an electro-optics code. A position sensitive anode board at the back of the stack of MSBs provides 2-D readout. This presentation discusses the trade studies performed in the design of the MSBs, the measurements of SEY from various electro-emissive materials, the electro-optics simulations conducted, the design of the 2-D readout, and the mechanical aspects of the LAMPA design, in order to achieve a gain of > 104 in an 8-stage stack of MSBs, suitable for use with various scintillators when coupled to an appropriate photocathode.

  1. Time estimation with multichannel digital silicon photomultipliers.

    Science.gov (United States)

    Venialgo, Esteban; Mandai, Shingo; Gong, Tim; Schaart, Dennis R; Charbon, Edoardo

    2015-03-21

    Accuracy in timemark estimation is crucial for time-of-flight positron emission tomography, in order to ensure high quality images after reconstruction. Since the introduction of multichannel digital silicon photomultipliers, it is possible to acquire several photoelectron timestamps for each individual gamma event. We study several timemark estimators based on multiple photoelectron timestamps by means of a comprehensive statistical model. In addition, we calculate the MSE of the estimators in comparison to the Cramér-Rao lower bound as a function of the system design parameters. We investigate the effect of skipping some of the photoelectron timestamps, which is a direct consequence of the limited number of time-to-digital converters and we propose a technique to compensate for this effect. In addition, we carry out an extensive analysis to evaluate the influence of dark counts on the detector timing performance. Moreover, we investigate the improvement of the timing performance that can be obtained with dark count filtering and we propose an appropriate filtering method based on measuring the time difference between sorted timestamps. Finally, we perform a full Monte Carlo simulation to compare different timemark estimators by exploring several system design parameters. It is demonstrated that a simple weighted-average estimator can achieve a comparable performance as the more complex maximum likelihood estimator.

  2. Qubit readout with the Josephson Photomultiplier

    Science.gov (United States)

    Ribeill, Guilhem

    Recent demonstrations of error correction in many qubit circuits, as well as efforts to build a logical qubit, have shown the need for a simple and scalable superconducting quantum bit (qubit) readout. Current solutions based on heterodyne detection and cryogenic amplification of microwave readout tones may prove difficult to scale, while photon counting presents an attractive alternative. However, the development of counters operating at these frequencies has proved technically challenging. In this thesis, we describe the development of the Josephson Photomultiplier (JPM), a microwave photon counting circuit. We discuss the JPM theoretically, and describe the fabrication of the JPM using standard thin film lithography techniques. We measure its properties as a microwave photon counter using a qubit as an in-situ calibrated source of photons. We measure a JPM quantum efficiency at the few percent level. We then use the JPM to perform readout of a transmon qubit in both the dispersive and bright regimes. We observe raw measurement fidelities of 35% and 62% respectively. We discuss how the JPM and measurement protocol could be further optimized to achieve fidelities in excess of 90%.

  3. Radiation Damage Studies of Silicon Photomultipliers

    CERN Document Server

    Bohn, P; Hazen, E.; Heering, A.; Rohlf, J.; Freeman, J.; Los, Sergey V.; Cascio, E.; Kuleshov, S.; Musienko, Y.; Piemonte, C.

    2008-01-01

    We report on the measurement of the radiation hardness of silicon photomultipliers (SiPMs) manufactured by Fondazione Bruno Kessler in Italy (1 mm$^2$ and 6.2 mm$^2$), Center of Perspective Technology and Apparatus in Russia (1 mm$^2$ and 4.4 mm$^2$), and Hamamatsu Corporation in Japan (1 mm$^2$). The SiPMs were irradiated using a beam of 212 MeV protons at Massachusetts General Hospital, receiving fluences of up to $3 \\times 10^{10}$ protons per cm$^2$ with the SiPMs at operating voltage. Leakage currents were read continuously during the irradiation. The delivery of the protons was paused periodically to record scope traces in response to calibrated light pulses to monitor the gains, photon detection efficiencies, and dark counts of the SiPMs. The leakage current and dark noise are found to increase with fluence. Te leakage current is found to be proportional to the mean square deviation of the noise distribution, indicating the dark counts are due to increased random individual pixel activation, while SiPM...

  4. A novel Silicon Photomultiplier with bulk integrated quench resistors: utilization in optical detection and tracking applications for particle physics

    Science.gov (United States)

    Petrovics, Stefan; Andricek, Ladislav; Diehl, Inge; Hansen, Karsten; Jendrysik, Christian; Krueger, Katja; Lehmann, Raik; Ninkovic, Jelena; Reckleben, Christian; Richter, Rainer; Schaller, Gerhard; Schopper, Florian; Sefkow, Felix

    2017-02-01

    Silicon Photomultipliers (SiPMs) are a promising candidate for replacing conventional photomultiplier tubes (PMTs) in many applications, thanks to ongoing developments and advances in their technology. Conventional SiPMs are generally an array of avalanche photo diodes, operated in Geiger mode and read out in parallel, thus leading to the necessity of a high ohmic quenching resistor. This resistor enables passive quenching and is usually located on top of the array, limiting the fill factor of the device. In this paper, a novel detector concept with a bulk integrated quenching resistor will be recapped. In addition, due to other advantages of this novel detector design, a new concept, in which these devices will be utilized as tracking detectors for particle physics applications will be introduced, as well as first simulation studies and experimental measurements of this new approach.

  5. FAMOUS – A prototype silicon photomultiplier telescope for the fluorescence detection of ultra-high-energy cosmic rays

    Directory of Open Access Journals (Sweden)

    Middendorf Lukas

    2013-06-01

    Full Text Available Due to their high photon detection efficiency, silicon photomultipliers (SiPMs promise to increase the sensitivity of today's fluorescence telescopes which use photomultiplier tubes to detect light originating from extensive air showers. On the other hand, drawbacks like a small sensitive area, a strong temperature dependence, a high noise rate and a reduced dynamic range have to be managed. We present plans for FAMOUS, a prototype fluorescence telescope using SiPMs and a special light collecting optical system of Winston cones to increase the sensitive area. The prototype will make use of a Fresnel lens. For several different types of SiPMs we measured their characteristics. Moreover, we will present the R&D in compact modular electronics using photon counting techniques. An evaluation of the performance of the optical telescope design is performed by means of a full detector simulation.

  6. Hybrid modeling of convective laminar flow in a permeable tube associated with the cross-flow process

    Science.gov (United States)

    Venezuela, A. L.; Pérez-Guerrero, J. S.; Fontes, S. R.

    2009-03-01

    The confined flows in tubes with permeable surfaces are associated to tangential filtration processes (microfiltration or ultrafiltration). The complexity of the phenomena do not allow for the development of exact analytical solutions, however, approximate solutions are of great interest for the calculation of the transmembrane outflow and estimate of the concentration polarization phenomenon. In the present work, the generalized integral transform technique (GITT) was employed in solving the laminar and permanent flow in permeable tubes of Newtonian and incompressible fluid. The mathematical formulation employed the parabolic differential equation of chemical species conservation (convective-diffusive equation). The velocity profiles for the entrance region flow, which are found in the connective terms of the equation, were assessed by solutions obtained from literature. The velocity at the permeable wall was considered uniform, with the concentration at the tube wall regarded as variable with an axial position. A computational methodology using global error control was applied to determine the concentration in the wall and concentration boundary layer thickness. The results obtained for the local transmembrane flux and the concentration boundary layer thickness were compared against others in literature.

  7. Simulating Silicon Photomultiplier Response to Scintillation Light

    Science.gov (United States)

    Jha, Abhinav K.; van Dam, Herman T.; Kupinski, Matthew A.; Clarkson, Eric

    2015-01-01

    The response of a Silicon Photomultiplier (SiPM) to optical signals is affected by many factors including photon-detection efficiency, recovery time, gain, optical crosstalk, afterpulsing, dark count, and detector dead time. Many of these parameters vary with overvoltage and temperature. When used to detect scintillation light, there is a complicated non-linear relationship between the incident light and the response of the SiPM. In this paper, we propose a combined discrete-time discrete-event Monte Carlo (MC) model to simulate SiPM response to scintillation light pulses. Our MC model accounts for all relevant aspects of the SiPM response, some of which were not accounted for in the previous models. We also derive and validate analytic expressions for the single-photoelectron response of the SiPM and the voltage drop across the quenching resistance in the SiPM microcell. These analytic expressions consider the effect of all the circuit elements in the SiPM and accurately simulate the time-variation in overvoltage across the microcells of the SiPM. Consequently, our MC model is able to incorporate the variation of the different SiPM parameters with varying overvoltage. The MC model is compared with measurements on SiPM-based scintillation detectors and with some cases for which the response is known a priori. The model is also used to study the variation in SiPM behavior with SiPM-circuit parameter variations and to predict the response of a SiPM-based detector to various scintillators. PMID:26236040

  8. Silicon photomultipliers detectors for next generation high-energy space telescopes

    Science.gov (United States)

    Lacombe, K.; Knödlseder, J.; Delaigue, S.; Gimenez, T.; Houret, B.; Mourey, V.; Ramon, P.; Virmontois, C.

    2016-09-01

    Photon detection is a central element of any high-energy astronomy instrumentation. One classical setup that has proven successful in many missions is the combination of photomultiplier tubes (PMTs) with scintillators, converting incoming high-energy photons into visible light, which in turn is converted in an electrical impulse. Although being extremely sensitive and rapid, PMTs have the drawback of being bulky, fragile, and require a high-voltage power supply of up to several thousand volts. Recent technological advances in the development of silicon photomultipliers (SiPM) make them a promising alternative to PMTs in essentially all their applications. We have started a RD program to assess the possibility of using SiPMs for space-based applications in the domain of high-energy astronomy. We will present results of our characterization studies of SiPMs from 3 manufacturers. Each SiPM detector has been tested inside a dedicated vacuum chamber and at low temperature to assess its performance in a representative space environment. Irradiation tests are scheduled to understand the susceptibility of SiPM to radiation damage. After comparison, we will select a baseline detector and design a specific front-end electronics and mechanical system. Furthermore, we plan to develop a low noise voltage power supply that ensures the stability of the SiPMs and to study their coupling to scintillators. Finally, our ultimate goal is to qualify the system for a space Technical Readiness Level of 5.

  9. Silicon Photo-Multiplier Readouts for Scintillators in High-Energy Astronomy

    Science.gov (United States)

    Bloser, Peter F.; Legere, Jason S.; Bancroft, Christopher M.; McConnell, Mark L.; Ryan, James M.

    2008-01-01

    New scintillator materials have recently been shown to hold great potential for low-cost, reliable gamma-ray detectors in high-energy astronomy. New devices for the detection of scintillation light promise to make scintillator-based instruments even more attractive by reducing mass and power requirements,in particular, silicon photo-multipliers (SiPMs) are starting to become commercially available that offer gains and quantum efficiencies similar to those of photo-multiplier tubes (PMTs), but with greatly reduced mass, high ruggedness, low voltage requirements, and no sensitivity to magnetic fields. We have conducted laboratory tests of a sample of commercially available SiPMs coupled to LaBr3;Ce, a scintillator of relevance to to future high-energy astrophysics missions. We present results for gamma-ray spectroscopy. compare the SiPM performance to that of a PMT, and discuss the extent to which SiPMs offer significant advantages for scintillator-based space missions.

  10. Progress towards a 256 channel multi-anode microchannel plate photomultiplier system with picosecond timing.

    Science.gov (United States)

    Lapington, J S; Ashton, T J R; Ross, D; Conneely, T

    2012-12-11

    Despite the rapid advances in solid state technologies such as the silicon photomultiplier (SiPM), microchannel plate (MCP) photomultipliers still offer a proven and practical technological solution for high channel count pixellated photon-counting systems with very high time resolution. We describe progress towards a 256 channel optical photon-counting system using CERN-developed NINO and HTDC ASICs, and designed primarily for time resolved spectroscopy in life science applications. Having previously built and demonstrated a 18 mm diameter prototype tube with an 8×8 channel readout configuration and <43 ps rms single photon timing resolution, we are currently developing a 40 mm device with a 32×32 channel readout. Initially this will be populated with a 256 channel electronics system comprising four sets of modular 64 channel preamplifier/discriminator, and time-to-digital converter units, arranged in a compact three dimensional configuration. We describe the detector and electronics design and operation, and present performance measurements from the 256 channel development system. We discuss enhancements to the system including higher channel count and the use of application specific on-board signal processing capabilities.

  11. Prototype of a silicon photomultiplier upgrade for the MAGIC telescopes camera

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, Alexander; Mazin, Daniel; Bangale, Priyadarshini; Dettlaff, Antonios; Fink, David; Grundner, Felix; Haberer, Werner; Maier, Roland; Mirzoyan, Razmik; Podkladkin, Sergey; Teshima, Masahiro; Wetteskind, Holger [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Muenchen (Germany)

    2015-07-01

    The MAGIC collaboration operates two 17 m diameter Imaging Atmospheric Cherenkov Telescopes on the Canary Island La Palma. Each of the two telescopes is currently equipped with 1039 photomultiplier tubes (PMTs). Due to the advances in the development of Silicon Photomultipliers (SiPMs), they are becoming a widely used alternative to PMTs in many research fields including Cherenkov astronomy. Within the Otto-Hahn group at the MPI for physics we are developing a SiPM based detector module for a possible upgrade of the MAGIC cameras and also for future experiments as, e.g., the Cherenkov Telescope Array (CTA). SiPMs have a smaller detector size that the 1-inch diameter PMTs used in MAGIC and we, therefore, make use of a matrix of SiPMs to cover the same area. We optimized the light concentrator (Winston cone) for the angular acceptance of the SiPMs using ray tracing simulations and developed an analog summation circuit to sum up and amplify the SiPM signals. We will present the results of the simulations as well as a schematic structure of the detector and compare our SiPM module with the established PMT modules.

  12. Silicon Photo-Multiplier Readouts for Scintillators in High-Energy Astronomy

    Science.gov (United States)

    Bloser, Peter F.; Legere, Jason S.; Bancroft, Christopher M.; McConnell, Mark L.; Ryan, James M.

    2008-01-01

    New scintillator materials have recently been shown to hold great potential for low-cost, reliable gamma-ray detectors in high-energy astronomy. New devices for the detection of scintillation light promise to make scintillator-based instruments even more attractive by reducing mass and power requirements,in particular, silicon photo-multipliers (SiPMs) are starting to become commercially available that offer gains and quantum efficiencies similar to those of photo-multiplier tubes (PMTs), but with greatly reduced mass, high ruggedness, low voltage requirements, and no sensitivity to magnetic fields. We have conducted laboratory tests of a sample of commercially available SiPMs coupled to LaBr3;Ce, a scintillator of relevance to to future high-energy astrophysics missions. We present results for gamma-ray spectroscopy. compare the SiPM performance to that of a PMT, and discuss the extent to which SiPMs offer significant advantages for scintillator-based space missions.

  13. Silicon photomultipliers with bulk-integrated quenching resistor: first results of characterization

    Energy Technology Data Exchange (ETDEWEB)

    Jendrysik, Christian; Andricek, Ladislav; Liemann, Gerhard; Moser, Hans-Guenther; Ninkovic, Jelena; Richter, Rainer [Max-Planck-Institut fuer Physik, Halbleiterlabor, Muenchen (Germany); Lutz, Gerhard [PNSensor GmbH, Muenchen (Germany)

    2011-07-01

    For future experiments in high energy physics detectors with high photon detection efficiencies (PDE) and ability to work in high magnetic fields are in the focus of research. Silicon photomultipliers (SiPM), arrays of Geiger-mode avalanche photodiodes, tend to replace conventional photomultiplier tubes in many applications. Conventional SiPMs use high-ohmic polysilicon as quenching resistor, which forms a barrier for incident light, thus decreasing the PDE. Furthermore it's also one of the cost driving technological issues in fabrication. By integrating the quenching resistor into the silicon bulk obstacles for light within the active area can be omitted and the fill factor of the device is only limited by the gaps necessary for optical crosstalk suppression. So this device is a promising candidate to achieve maximum PDE of up to 70%. In addition the absence of lateral high field regions on surface should improve the radiation hardness of the device. Results of the characterization of the in-house prototype production are presented.

  14. Efficiency and timing resolution of scintillator tiles read out with silicon photomultipliers

    Science.gov (United States)

    Pooth, O.; Weingarten, S.; Weinstock, L.

    2016-01-01

    Silicon photomultipliers (SiPM) are semiconductor photo sensors that have the potential to replace photomultiplier tubes (PMT) in various fields of application. We present detectors consisting of 30 × 30 × 0.5 cm3 fast plastic scintillator tiles read out with SiPMs. The detectors offer great electronic and mechanical advantages over the classical PMT-scintillator combination. SiPMs are very compact devices that run independent of magnetic fields at low voltages and no light guides between the scintillator and the SiPM are necessary in the presented layouts. Three prototypes, two of which with integrated wavelength shifting fibres, have been tested in a proton beam at the COSY accelerator at Forschungszentrum Jülich. The different layouts are compared in terms of most probable pulse height, detection efficiency and noise behaviour as well as timing resolution. The spatial distributions of these properties across the scintillator surface are presented. The best layout can be operated at a mean efficiency of bar epsilon=99.9 % while sustaining low noise rates in the order of 10 Hz with a timing resolution of less than 3 ns. Both efficiency and timing resolution show good spatial homogeneity.

  15. Sub-aquatic response of a scintillator, fibre optic and silicon photomultiplier based radiation sensor

    Science.gov (United States)

    Jackson, Sarah F.; Monk, Stephen D.; Stanley, Steven J.; Lennox, Kathryn

    2014-07-01

    We describe an attempt at the utilisation of two low level light sensors to improve on the design of a dose monitoring system, specifically for underwater applications with consideration for the effects of water attenuation. The gamma radiation ‘RadLine®’ detector consists of an inorganic scintillating crystal coupled to a fibre optic cable which transports scintillation photons, up to hundreds of metres, to an optical sensor. Analysed here are two contemporary technologies; SensL's MiniSL a silicon photomultiplier (SiPM) and a Sens-Tech photon counting photomultiplier tube (PMT). A clinical radiotherapy linear accelerator (linac) is implemented as test beam, subjecting the RadLine® to a highly controlled dose rate (ranging from 0 Sv h-1 to 320 Sv h-1), averaging at 2 MeV in energy. The RadLine's underwater dose monitoring capabilities are tested with the aid of epoxy resin ‘solid water’ phantom blocks, used as a substitute for water. Our results show that the MiniSL SiPM is unsuitable for this application due to extremely high background noise levels, however the Sens-Tech PMT performs satisfactorily and the detected dose rate due to the effects of water attenuation compares strongly with MCNP simulation data and NIST database values. We conclude that the PMT shows promise for its ultimate use in the First Generation Magnox Storage Pond (FGMSP) on the Sellafield site.

  16. Silicon Photomultiplier Research and Development Studies for the Large Size Telescope of the Cherenkov Telescope Array

    CERN Document Server

    Rando, Riccardo; Dazzi, Francesco; De Angelis, Alessandro; Dettlaff, Antonios; Dorner, Daniela; Fink, David; Fouque, Nadia; Grundner, Felix; Haberer, Werner; Hahn, Alexander; Hermel, Richard; Korpar, Samo; Mezek, Gašper Kukec; Maier, Ronald; Manea, Christian; Mariotti, Mosè; Mazin, Daniel; Mehrez, Fatima; Mirzoyan, Razmik; Podkladkin, Sergey; Reichardt, Ignasi; Rhode, Wolfgang; Rosier, Sylvie; Schultz, Cornelia; Stella, Carlo; Teshima, Masahiro; Wetteskind, Holger; Zavrtanik, Marko

    2015-01-01

    The Cherenkov Telescope Array (CTA) is the the next generation facility of imaging atmospheric Cherenkov telescopes; two sites will cover both hemispheres. CTA will reach unprecedented sensitivity, energy and angular resolution in very-high-energy gamma-ray astronomy. Each CTA array will include four Large Size Telescopes (LSTs), designed to cover the low-energy range of the CTA sensitivity ($\\sim$20 GeV to 200 GeV). In the baseline LST design, the focal-plane camera will be instrumented with 265 photodetector clusters; each will include seven photomultiplier tubes (PMTs), with an entrance window of 1.5 inches in diameter. The PMT design is based on mature and reliable technology. Recently, silicon photomultipliers (SiPMs) are emerging as a competitor. Currently, SiPMs have advantages (e.g. lower operating voltage and tolerance to high illumination levels) and disadvantages (e.g. higher capacitance and cross talk rates), but this technology is still young and rapidly evolving. SiPM technology has a strong pot...

  17. Development of a Modern Cosmic Ray Telescope based on Silicon Photomultipliers for use in High Schools

    Science.gov (United States)

    Ruiz Castruita, Daniel; Niduaza, Rommel; Hernandez, Victor; Knox, Adrian; Ramos, Daniel; Fan, Sewan; Fatuzzo, Laura

    2015-04-01

    Lately, a new light sensor technology based on the breakdown phenomenon in the reverse biased silicon diode has found many applications that span from particle physics to medical imaging science. The silicon photomultiplier (SiPM) has several notable advantages compared to conventional photomultiplier tubes which include: lower cost, lower operating voltage and the ability to measure very weak light signals at the single photon level. At this conference meeting, we describe our efforts to implement SiPMs as read out light detectors for plastic scintillators in a cosmic ray telescope for use in high schools. In particular, we describe our work in designing, testing and assembling the cosmic ray telescope. We include a high gain preamplifier, a custom coincidence circuit using fast comparators to discriminate the SiPM signal amplitudes and a monovibrator IC for lengthening the singles and coincidence logic pulses. An Arduino micro-controller and program sketches are used for processing and storing the singles and coincidence counts data. Results from our measurements would be illustrated and presented. US Department of Education Title V Grant Award PO31S090007.

  18. CLARO: an ASIC for high rate single photon counting with multi-anode photomultipliers

    Science.gov (United States)

    Baszczyk, M.; Carniti, P.; Cassina, L.; Cotta Ramusino, A.; Dorosz, P.; Fiorini, M.; Gotti, C.; Kucewicz, W.; Malaguti, R.; Pessina, G.

    2017-08-01

    The CLARO is a radiation-hard 8-channel ASIC designed for single photon counting with multi-anode photomultiplier tubes. Each channel outputs a digital pulse when the input signal from the photomultiplier crosses a configurable threshold. The fast return to baseline, typically within 25 ns, and below 50 ns in all conditions, allows to count up to 107 hits/s on each channel, with a power consumption of about 1 mW per channel. The ASIC presented here is a much improved version of the first 4-channel prototype. The threshold can be precisely set in a wide range, between 30 ke- (5 fC) and 16 Me- (2.6 pC). The noise of the amplifier with a 10 pF input capacitance is 3.5 ke- (0.6 fC) RMS. All settings are stored in a 128-bit configuration and status register, protected against soft errors with triple modular redundancy. The paper describes the design of the ASIC at transistor-level, and demonstrates its performance on the test bench.

  19. Ear Tubes

    Science.gov (United States)

    ... ENTCareers Marketplace Find an ENT Doctor Near You Ear Tubes Ear Tubes Patient Health Information News media ... and throat specialist) may be considered. What are ear tubes? Ear tubes are tiny cylinders placed through ...

  20. A 1 mm Scintillating Fibre Tracker Readout by a Multi-anode Photomultiplier

    CERN Document Server

    Leverington, B D; Campana, P; Rosellini, R

    2011-01-01

    This note describes a prototype particle tracking detector constructed with 1 mm plastic scintillating fibres with a 64 channel Hamamatsu H8500 flat-panel multi-anode photomultiplier readout. Cosmic ray tracks from an array of 11 gas-filled drift tubes were matched to signals in the scintillating fibres in order to measure the resolution and efficiency of tracks reconstructed in the fibre-based tracker. A GEANT4 detector simulation was also developed to compare cosmic ray data with MC results and is discussed in the note. Using the parameters measured in this experimental setup, modified fibre tracker designs are suggested to improve resolution and efficiency in future prototypes to meet modern detector specifications.

  1. Current feedback operational amplifiers as fast charge sensitive preamplifiers for photomultiplier read out

    Energy Technology Data Exchange (ETDEWEB)

    Giachero, A; Gotti, C; Maino, M; Pessina, G, E-mail: claudio.gotti@mib.infn.it [INFN - Sezione di Milano-Bicocca, I-20126, Milano (Italy)

    2011-05-01

    Fast charge sensitive preamplifiers were built using commercial current feedback operational amplifiers for fast read out of charge pulses from a photomultiplier tube. Current feedback opamps prove to be particularly well suited for this application where the charge from the detector is large, of the order of one million electrons, and high timing resolution is required. A proper circuit arrangement allows very fast signals, with rise times down to one nanosecond, while keeping the amplifier stable. After a review of current feedback circuit topology and stability constraints, we provide a 'recipe' to build stable and very fast charge sensitive preamplifiers from any current feedback opamp by adding just a few external components. The noise performance of the circuit topology has been evaluated and is reported in terms of equivalent noise charge.

  2. Current feedback operational amplifiers as fast charge sensitive preamplifiers for photomultiplier read out

    Science.gov (United States)

    Giachero, A.; Gotti, C.; Maino, M.; Pessina, G.

    2011-05-01

    Fast charge sensitive preamplifiers were built using commercial current feedback operational amplifiers for fast read out of charge pulses from a photomultiplier tube. Current feedback opamps prove to be particularly well suited for this application where the charge from the detector is large, of the order of one million electrons, and high timing resolution is required. A proper circuit arrangement allows very fast signals, with rise times down to one nanosecond, while keeping the amplifier stable. After a review of current feedback circuit topology and stability constraints, we provide a "recipe" to build stable and very fast charge sensitive preamplifiers from any current feedback opamp by adding just a few external components. The noise performance of the circuit topology has been evaluated and is reported in terms of equivalent noise charge.

  3. An investigation of optimal photomultiplier signal delay method on detector time resolution in positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Aykac, Mehmet, E-mail: aykac2000@yahoo.com [Siemens Medical Systems, Molecular Imaging, Knoxville, TN 37932 (United States); Cho, Sanghee [Siemens Medical Systems, Molecular Imaging, Knoxville, TN 37932 (United States)

    2011-06-11

    Cerium doped fast scintillators such as LSO and LaBr{sub 3} and fast photomultiplier tubes (PMT) have dramatically improved the timing performance of PET scanners in the last several years. Recent developments in high speed electronics brought new opportunities to understand and process the photosensor signals. In this work, a digital time alignment method is introduced and implemented using fast scintillators and photosensors with the combination of high speed digital electronics. A method was tested on a light sharing 13x13 LSO detector and a 310 ps average crystal time resolution was measured against a single LSO reference detector using optimal signal delays based on a digital leading edge (LE) triggering scheme in a 250 ps sampling interval. The improvement with this method was measured to be about 5.2% compared to the no time alignment case. The crystal time resolution improvements against a single LSO reference detector ranged from 2% to 9% after optimal signal delay implementation.

  4. Cathode Position Response of Large-Area Photomultipliers Under a Magnetic Field

    CERN Document Server

    Koblesky, T; Polly, C; Peng, J C

    2011-01-01

    With the increasingly common use of large area PMTs (photomultiplier tubes) for nuclear and particle physics experiments, information on the position dependent magnetic field effects across the PMT's photocathode is important to effectively analyze and understand data collected from PMTs. Using an automated two-dimensional scanner, we have measured the PMT response to an external magnetic field as a function of the cathode position impinged by a collimated light source. This study shows a clear dependence on the cathode position in both collection efficiency and gain of the PMT in the presence of a magnetic field. In particular, a pronounced valley in the collection efficiency is observed for certain locations of the cathode when the magnetic field is transverse to the PMT axis. The pattern of the position dependence is presented for several different magnitudes and orientations of the magnetic field relative to the PMT.

  5. A monolithic charge-to-amplitude converter (QAC) chip for fast readout of photomultiplier

    CERN Document Server

    Inaba, S; Takamatsu, K; Inaba, M; Baba, T; Sugonyaev, V P; Melebeck, T; Van Bogget, U

    2000-01-01

    A fast charge-to-amplitude converter (QAC) chip has been developed for the readout electronics of the electromagnetic calorimeter (ECAL) of the COMPASS experiment at CERN SPS. It is fabricated using a new advanced complementary bipolar process from Harris Semiconductor with intrinsic radiation hardness. The new QAC chip performs the conversion of fast current pulses generated by a photomultiplier tube (PMT) into voltage signals. The output voltage of the QAC is directly proportional to the input current signal. The circuit block diagram, main features and characteristics of the chip are described. Simulation curves as well as test results of QAC prototypes are presented. They show excellent performances for the COMPASS experiment as well as for uses in high energy and nuclear physics experiments to manage fast current signals.

  6. APPLICATION OF MULTILAYER FILM CONFIGURATION TO PROTECT PHOTOMULTIPLIER AGAINST EXTERNAL STATIC MAGNETIC FIELDS

    Directory of Open Access Journals (Sweden)

    A. G. Batische

    2012-01-01

    Full Text Available The effectiveness of the screening constant magnetic field is multi-layered film screens system of NiFe/Cu, formed on the cylindrical housing of photomultiplier tubes, and compared with screen-based steel material – brand 80NHS permalloy. It is shown that the most effective is the screen on the basis of the multilayered film screens, which provide shielding effectiveness value 8–10 in magnetic fields with induction of 0,1–1 mT, and 80–100 – in magnetic fields with induction of 2–4 mT , which is 4–5 times higher than for the screen of the material 80NHS.

  7. Position-sensitive gaseous photomultipliers research and applications

    CERN Document Server

    Francke, Tom; Peskov, Vladimir

    2016-01-01

    Gaseous photomultipliers are defined as gas-filled devices capable of recording single ultraviolet (UV) and visible photons with high position resolution. Used in a variety of research areas, these detectors can be paired with computers to treat and store imaging information of UV-light. Position-Sensitive Gaseous Photomultipliers: Research and Applications explores the advancement of gaseous detectors as applied for single photon detection. Emphasizing emerging perspectives and new ways to apply gaseous detectors across research fields, this research-based publication is an essential reference source for engineers, physicists, graduate-level students, and researchers.

  8. Development of scintillating crystal hybrid photon detectors for the KM3NeT (km{sup 3}-scale) deep-sea neutrino telescope

    Energy Technology Data Exchange (ETDEWEB)

    Al Samarai, I.; Busto, J. [Centre de Physique des Particules de Marseille, 163 Avenue de Luminy, Case 907, 13288 Marseille Cedex 09 (France); Combettes, B.; Dehaine, A.-G. [Photonis S.A.S., Avenue Roger Roncier, 19106 Brive la Gaillarde (France); Dornic, D. [Centre de Physique des Particules de Marseille, 163 Avenue de Luminy, Case 907, 13288 Marseille Cedex 09 (France); Hallewell, G. [Centre de Physique des Particules de Marseille, 163 Avenue de Luminy, Case 907, 13288 Marseille Cedex 09 (France)], E-mail: gregh@cppm.in2p3.fr

    2009-10-21

    Scintillating crystal-based hybrid photon detectors have been demonstrated as viable single photon detectors since 1996 in the Lake Baikal neutrino telescope. Prior to this, the Philips XP2600 was developed under the DUMAND program, while more recently, developments at CERN have demonstrated the advantages of a true concentric geometry with a scintillator at the geometric centre of a spherical photocathode, giving almost 100% electrostatic collection efficiency over 3{pi} solid angle coverage. We have started to develop a new series of quasi-spherical crystal hybrid photon detectors starting at 8 in. and progressing toward the maximum that can be fitting in a standard 17 in. optical pressure sphere for a future large deep-sea neutrino telescope. The thrust of this R and D will be to investigate the industrialisation of these sensors to the point where they represent a significant cost reduction per cubic kilometre of instrumented volume compared to conventional large hemispherical photomultiplier tubes, thereby allowing for extremely large telescope target volumes. Such gains will arise through an all-glass envelope, internal processing of a standard or enhanced bialkali photocathode, and either from cost reductions in the central scintillating crystal or the use of a deposited phosphor viewed by a small photomultiplier tube. Details of the development program and recent progress in the characterisation of prototypes are presented.

  9. A Comprehensive Model of the Response of Silicon Photomultipliers

    NARCIS (Netherlands)

    van Dam, Herman T.; Seifert, Stefan; Vinke, Ruud; Dendooven, Peter; Lohner, Herbert; Beekman, Freek J.; Schaart, Dennis R.

    The response of a silicon photomultiplier (SiPM) to optical signals is inherently nonproportional due to saturation, afterpulsing, and crosstalk. Existing models of the SiPM response do not account for all of these effects, and therefore, these models are not sufficiently accurate for many

  10. Timing optimization utilizing order statistics and multichannel digital silicon photomultipliers

    NARCIS (Netherlands)

    Mandai, S.; Venialgo, E.; Charbon, E.

    2014-01-01

    We present an optimization technique utilizing order statistics with a multichannel digital silicon photomultiplier (MD-SiPM) for timing measurements. Accurate timing measurements are required by 3D rangefinding and time-of-flight positron emission tomography, to name a few applications. We have

  11. A Comprehensive Model of the Response of Silicon Photomultipliers

    NARCIS (Netherlands)

    Van Dam, H.T.; Seifert, S.; Vinke, R.; Dendooven, P.; Löhner, H.; Beekman, F.J.; Schaart, D.R.

    2010-01-01

    The response of a silicon photomultiplier (SiPM) to optical signals is inherently nonproportional due to saturation, afterpulsing, and crosstalk. Existing models of the SiPM response do not account for all of these effects, and therefore, these models are not sufficiently accurate for many

  12. A Comprehensive Model of the Response of Silicon Photomultipliers

    NARCIS (Netherlands)

    van Dam, Herman T.; Seifert, Stefan; Vinke, Ruud; Dendooven, Peter; Lohner, Herbert; Beekman, Freek J.; Schaart, Dennis R.

    2010-01-01

    The response of a silicon photomultiplier (SiPM) to optical signals is inherently nonproportional due to saturation, afterpulsing, and crosstalk. Existing models of the SiPM response do not account for all of these effects, and therefore, these models are not sufficiently accurate for many applicati

  13. Timing optimization utilizing order statistics and multichannel digital silicon photomultipliers

    NARCIS (Netherlands)

    Mandai, S.; Venialgo, E.; Charbon, E.

    2014-01-01

    We present an optimization technique utilizing order statistics with a multichannel digital silicon photomultiplier (MD-SiPM) for timing measurements. Accurate timing measurements are required by 3D rangefinding and time-of-flight positron emission tomography, to name a few applications. We have dem

  14. Timing optimization utilizing order statistics and multichannel digital silicon photomultipliers

    NARCIS (Netherlands)

    Mandai, S.; Venialgo, E.; Charbon, E.

    2014-01-01

    We present an optimization technique utilizing order statistics with a multichannel digital silicon photomultiplier (MD-SiPM) for timing measurements. Accurate timing measurements are required by 3D rangefinding and time-of-flight positron emission tomography, to name a few applications. We have dem

  15. Calibration of photomultipliers gain used in the J-PET detector

    CERN Document Server

    Bednarski, T; Moskal, P; Białas, P; Giergiel, K; Kapłon, Ł; Kochanowski, A; Korcyl, G; Kowal, J; Kowalski, P; Kozik, T; Krzemień, W; Molenda, M; Moskal, I; Niedźwiecki, Sz; Pałka, M; Pawlik, M; Raczyński, L; Rudy, Z; Salabura, P; Sharma, N G; Silarski, M; Słomski, A; Smyrski, J; Strzelecki, A; Szymański, K; Wiślicki, W; Witkowski, P; Zieliński, M; Zoń, N

    2013-01-01

    Photomultipliers are commonly used in commercial PET scanner as devices which convert light produced in scintillator by gamma quanta from positron-electron annihilation into electrical signal. For proper analysis of obtained electrical signal, a photomultiplier gain curve must be known, since gain can be significantly different even between photomultipliers of the same model. In this article we describe single photoelectron method used for photomultipliers calibration applied for J-PET scanner, a novel PET detector being developed at the Jagiellonian University. Description of calibration method, an example of calibration curve and gain of few R4998 Hamamatsu photomultipliers are presented.

  16. Photocopia-A Unibody Mono-material Compact and Scalable Photomultiplier

    Energy Technology Data Exchange (ETDEWEB)

    Mulhollan, Gregory [Saxet Surface Science

    2014-12-01

    The Photocopia photomultiplier tube (PMT) takes advantage of two of the many unique properties of the hydrogenated amorphous silicon-germanium (a-SiGe) photoemitter material: its mechanical flexibility and mostly substrate-independent properties. The a-SiGe photoemitter has high secondary electron (SE) yield. It can be used both as the photocathode and as the gain medium. The active material can be grown on a flat, thin unibody substrate, formed and then “rolled up” ex situ. The completed structure would then be activated and sealed within a tube. The Ge component can be increased to enhance red-sensitivity. Compact sizes are possible, minimizing magnetic field effects. The Photocopia PMT will be a low cost alternative to MCPs for TOF detectors and provide better timing discrimination for Cherenkov detectors. Retention of the ability to activate to a normal photoyield state upon flexing (bending) the substrate of the a-SiGe material after growth, but prior to activation has been shown. The SE coefficient of the activated material has been characterized over the voltage range suitable for utilization as the gain material. The time response of the material is suited to PMT use.

  17. Silicon photomultipliers and their bio-medical applications

    Energy Technology Data Exchange (ETDEWEB)

    Grigoriev, Eugene [Institute for Theoretical and Experimental Physics (ITEP), B.Cheremushkinskaya 25, Moscow 117218 (Russian Federation) and Forimtech S.A., Route de Malagnou 32, Geneva 1208 (Switzerland)]. E-mail: grigoriev@forimtech.ch; Akindinov, Alexander [Institute for Theoretical and Experimental Physics (ITEP), B.Cheremushkinskaya 25, Moscow 117218 (Russian Federation); Breitenmoser, Marco [Forimtech S.A., Route de Malagnou 32, Geneva 1208 (Switzerland); Buono, Stefano [Advanced Accelerator Applications S.A (AAA), 20 rue Diesel, 01630 St. Genis Pouilly (France); Charbon, Edoardo [Ecole Politechnique Federale de Lausanne (EPFL), AQUA Group, Lausanne 1015 (Switzerland); Niclass, Cristiano [Ecole Politechnique Federale de Lausanne (EPFL), AQUA Group, Lausanne 1015 (Switzerland); Desforges, Iris [Forimtech S.A., Route de Malagnou 32, Geneva 1208 (Switzerland); Rocca, Roberto [Advanced Accelerator Applications S.A (AAA), 20 rue Diesel, 01630 St. Genis Pouilly (France)

    2007-02-01

    Single Photon Avalanche Diodes (SPADs) have been used for photon counting since the 1960s, but only in the recent decade multi-pixel structures based on SPAD-arrays and silicon photomultipliers have been developed. These devices are finding more and more applications in many fields, where detection of light at the level of a single photon is needed. Due to their exclusive properties (fast response, low operating voltage, single photon sensitivity at room temperature, extremely high gain, stability, compactness, robustness and low price), such sensors are successfully replacing traditional vacuum photomultipliers in many devices. The paper briefly describes the state of the art and suggests some new applications in biology and medicine.

  18. Precision analysis of the photomultiplier response to ultra low signals

    CERN Document Server

    Degtiarenko, Pavel

    2016-01-01

    A new mathematical model for the description of the photon detector response functions measured in conditions of low light is presented, together with examples of the observed photomultiplier signal amplitude distributions, successfully described using the parameterized model equation. As opposed to the previously known approximations, the new model describes the underlying discrete statistical behavior of the photoelectron cascade multiplication processes in photon detectors. Important features of the model include the ability to represent the true single-photoelectron spectra from different photomultipliers with a variety of parameterized shapes, reflecting the variability in the design and in the individual parameters of the detectors. The new software tool is available for evaluation of the detectors' performance, response, and efficiency parameters that may be used in various applications including the ultra low background experiments such as the searches for Dark Matter and rare decays, underground neut...

  19. Time and charge characterization of Hamamatsu Photonics silicon photomultipliers

    Directory of Open Access Journals (Sweden)

    Galetta G.

    2014-03-01

    Full Text Available Two Hamamatsu Photonics silicon photomultipliers (SiPM with same cell size 50×50 µm2 and different sensitive area (1×1 mm2 vs. 3×3 mm2 have been characterized in charge and time by means of a 409 nm pico-laser. The time resolution was studied for the detection of few photoelectrons. The results obtained are relevant for the employment of SiPM in ring imaging Cherenkov detectors (RICH.

  20. Performance of Several Solid State Photomultipliers with CLYC Scintillator

    CERN Document Server

    Mesick, Katherine E; Morrell, Jonathan T; Coupland, Daniel D S

    2015-01-01

    $Cs_2LiYCl_6:Ce^{3+}$ (CLYC) is an inorganic scintillator that has recently garnered attention for its ability to detect and discriminate between gammas and thermal neutrons. We investigate several important performance parameters of three different solid state photomultipliers (SSPMs) when reading out CLYC crystals: linearity, energy resolution, and pulse shape and discrimination ability. These performance parameters are assessed at a variety of temperatures between -20$^{\\circ}$C and +50$^{\\circ}$C.

  1. The new versatile general purpose surface-muon instrument (GPS) based on silicon photomultipliers for μSR measurements on a continuous-wave beam

    Science.gov (United States)

    Amato, A.; Luetkens, H.; Sedlak, K.; Stoykov, A.; Scheuermann, R.; Elender, M.; Raselli, A.; Graf, D.

    2017-09-01

    We report on the design and commissioning of a new spectrometer for muon-spin relaxation/rotation studies installed at the Swiss Muon Source (SμS) of the Paul Scherrer Institute (PSI, Switzerland). This new instrument is essentially a new design and replaces the old general-purpose surface-muon (GPS) instrument that has been for long the workhorse of the μSR user facility at PSI. By making use of muon and positron detectors made of plastic scintillators read out by silicon photomultipliers, a time resolution of the complete instrument of about 160 ps (standard deviation) could be achieved. In addition, the absence of light guides, which are needed in traditionally built μSR instrument to deliver the scintillation light to photomultiplier tubes located outside magnetic fields applied, allowed us to design a compact instrument with a detector set covering an increased solid angle compared with the old GPS.

  2. Characterization and optimization of Silicon Photomultipliers and small size scintillator tiles for future calorimeter applications

    CERN Document Server

    AUTHOR|(CDS)2095312; Horváth, Ákos

    For the active layers of highly granular sampling calorimeters, small scintillator tiles read out by Silicon Photomultipliers (SiPM) can be an interesting and cost effective alternative to silicon sensors. At CERN a test setup was realized for the development of new generations of calorimeters to characterize new types of Silicon Photomultipliers in terms of gain, noise, afterpulses and crosstalk and to study the impact of scintillator wrappings and the tile size on the measured light yield and uniformity. In this thesis work, the experimental setup is described and the steps for commissioning the equipment are discussed. Then, the temperature dependence of the Silicon Photomultiplier response will be investigated, including the dependence of bare Silicon Photomultipliers as well as Silicon Photomultipliers coupled to scintillator tiles. Finally, the tile-photomultiplier response for different tile sizes and coating options will be evaluated. The experimental setup will be extended to allow for the characteri...

  3. Study of silicon photomultipliers for the readout of scintillator crystals in the proposed GRIPS \\gamma-ray astronomy mission

    CERN Document Server

    Ulyanov, Alexei; McBreen, Sheila; Foley, Suzanne; Byrne, David

    2013-01-01

    Among the top priorities for high-energy astronomy in the coming decade are sensitive surveys in the hard X-ray/soft \\gamma-ray (10-600 keV) and medium-energy \\gamma-ray (0.2-80 MeV) bands. Historically, observations in the soft and medium energy \\gamma-ray bands have been conducted using detectors based on inorganic scintillators read out by photo-multiplier tubes (PMTs). These observations were limited by the modest energy and time resolution of traditional scintillator materials (e.g. NaI and CsI), and by the demands on mission resources imposed by the bulky, fragile, high-voltage PMTs. Recent technological advances in the development of both new scintillator materials (e.g. LaBr3:Ce, L(Y)SO) and new scintillation light readout devices (e.g. Silicon Photo-Multipliers) promise to greatly improve the observational capabilities of future scintillator-based \\gamma--ray telescopes, while retaining the relative simplicity, reliability, large collection volumes, and low-cost of scintillator instruments. We presen...

  4. Cherenkov luminescence measurements with digital silicon photomultipliers: a feasibility study.

    Science.gov (United States)

    Ciarrocchi, Esther; Belcari, Nicola; Guerra, Alberto Del; Cherry, Simon R; Lehnert, Adrienne; Hunter, William C J; McDougald, Wendy; Miyaoka, Robert S; Kinahan, Paul E

    2015-12-01

    A feasibility study was done to assess the capability of digital silicon photomultipliers to measure the Cherenkov luminescence emitted by a β source. Cherenkov luminescence imaging (CLI) is possible with a charge coupled device (CCD) based technology, but a stand-alone technique for quantitative activity measurements based on Cherenkov luminescence has not yet been developed. Silicon photomultipliers (SiPMs) are photon counting devices with a fast impulse response and can potentially be used to quantify β-emitting radiotracer distributions by CLI. In this study, a Philips digital photon counting (PDPC) silicon photomultiplier detector was evaluated for measuring Cherenkov luminescence. The PDPC detector is a matrix of avalanche photodiodes, which were read one at a time in a dark count map (DCM) measurement mode (much like a CCD). This reduces the device active area but allows the information from a single avalanche photodiode to be preserved, which is not possible with analog SiPMs. An algorithm to reject the noisiest photodiodes and to correct the measured count rate for the dark current was developed. The results show that, in DCM mode and at (10-13) °C, the PDPC has a dynamic response to different levels of Cherenkov luminescence emitted by a β source and transmitted through an opaque medium. This suggests the potential for this approach to provide quantitative activity measurements. Interestingly, the potential use of the PDPC in DCM mode for direct imaging of Cherenkov luminescence, as a opposed to a scalar measurement device, was also apparent. We showed that a PDPC tile in DCM mode is able to detect and image a β source through its Cherenkov radiation emission. The detector's dynamic response to different levels of radiation suggests its potential quantitative capabilities, and the DCM mode allows imaging with a better spatial resolution than the conventional event-triggered mode. Finally, the same acquisition procedure and data processing could be

  5. Study of Silicon Photomultipliers for the GRIPS Calorimeter Module

    Directory of Open Access Journals (Sweden)

    Alexei Ulyanov

    2013-01-01

    Full Text Available GRIPS is a proposed gamma-ray (200 keV to 80 MeV astronomy mission, which incorporates a pair-creation and Compton scattering telescope, along with X-ray and infrared telescopes. It will carry out a sensitive all-sky scanning survey, investigating phenomena such as gamma-ray bursts, blazars and core collapse supernovae. The main telescope is composed of a Si strip detector surroundedby a calorimeter with a fast scintillator material. We present the initial results of a study which considers the potential use of silicon photomultipliers in conjunction with the scintillator in the GRIPS calorimeter module.

  6. On the stochastic dependence between photomultipliers in the TDCR method

    Energy Technology Data Exchange (ETDEWEB)

    Bobin, C., E-mail: christophe.bobin@cea.fr [CEA, LIST, Laboratoire National Henri Becquerel (LNE-LNHB), F-91191 Gif-sur-Yvette Cedex (France); Thiam, C.; Chauvenet, B.; Bouchard, J. [CEA, LIST, Laboratoire National Henri Becquerel (LNE-LNHB), F-91191 Gif-sur-Yvette Cedex (France)

    2012-04-15

    The TDCR method (Triple to Double Coincidence Ratio) is widely implemented in National Metrology Institutes for activity primary measurements based on liquid scintillation counting. The detection efficiency and thereby the activity are determined using a statistical and physical model. In this article, we propose to revisit the application of the classical TDCR model and its validity by introducing a prerequisite of stochastic independence between photomultiplier counting. In order to support the need for this condition, the demonstration is carried out by considering the simple case of a monoenergetic deposition in the scintillation cocktail. Simulations of triple and double coincidence counting are presented in order to point out the existence of stochastic dependence between photomultipliers that can be significant in the case of low-energy deposition in the scintillator. It is demonstrated that a problem of time dependence arises when the coincidence resolving time is shorter than the time distribution of scintillation photons; in addition, it is shown that this effect is at the origin of a bias in the detection efficiency calculation encountered for the standardization of {sup 3}H. This investigation is extended to the study of geometric dependence between photomultipliers related to the position of light emission inside the scintillation vial (the volume of the vial is not considered in the classical TDCR model). In that case, triple and double coincidences are calculated using a stochastic TDCR model based on the Monte-Carlo simulation code Geant4. This stochastic approach is also applied to the standardization of {sup 51}Cr by liquid scintillation; the difference observed in detection efficiencies calculated using the standard and stochastic models can be explained by such an effect of geometric dependence between photomultiplier channels. - Highlights: Black-Right-Pointing-Pointer The TDCR model is revisited by introducing the condition of stochastic

  7. Detectors based on silicon photomultiplier arrays for medical imaging applications

    Energy Technology Data Exchange (ETDEWEB)

    Llosa, G.; Barrio, J.; Cabello, J.; Lacasta, C.; Oliver, J. F. [Instituto de Fisica Corpuscular - IFIC-CSIC/UVEG, Valencia (Spain); Rafecas, M. [Instituto de Fisica Corpuscular - IFIC-CSIC/UVEG, Valencia (Spain); Departamento de Fisica Atomica, Molecular Y Nuclear, Universitat de Valencia, Valencia (Spain); Stankova, V.; Solaz, C. [Instituto de Fisica Corpuscular - IFIC-CSIC/UVEG, Valencia (Spain); Bisogni, M. G.; Del Guerra, A. [Universite di Pisa, INFN Pisa, Pisa (Italy)

    2011-07-01

    Silicon photomultipliers (SiPMs) have experienced a fast development and are now employed in different research fields. The availability of 2D arrays that provide information of the interaction position in the detector has had a high interest for medical imaging. Continuous crystals combined with segmented photodetectors can provide higher efficiency than pixellated crystals and very high spatial resolution. The IRIS group at IFIC is working on the development of detector heads based on continuous crystals coupled to SiPM arrays for different applications, including a small animal PET scanner in collaboration with the Univ. of Pisa and INFN Pisa, and a Compton telescope for dose monitoring in hadron therapy. (authors)

  8. Large-aperture hybrid photo-detector

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, Y. [Institute for Particle and Nuclear Studies, The Graduate University for Advanced Studies, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Electron Tube Division, Hamamatsu Photonics K.K., 314-5 Shimokanzo, Iwata City 438-0193, Shizuoka (Japan)], E-mail: kawaiy@post.kek.jp; Nakayama, H.; Kusaka, A.; Kakuno, H.; Abe, T.; Iwasaki, M.; Aihara, H. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Tanaka, M. [Institute for Particle and Nuclear Studies, High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Shiozawa, M. [Institute for Cosmic Ray Research, University of Tokyo, Higashi-Mozumi, Kamioka-cho, Hida City, Gifu 506-1205 (Japan); Kyushima, H.; Suyama, M. [Electron Tube Division, Hamamatsu Photonics K.K., 314-5 Shimokanzo, Iwata City 438-0193, Shizuoka (Japan)

    2007-08-21

    We have developed the first complete large-aperture (13-inch diameter) hybrid photo-detector (HPD). The withstanding voltage problem has been overcome and we were able to attain an HPD operating voltage of +20 kV. Adoption of our newly developed backside illumination avalanche diode (AD) was also critical in successfully countering the additional problem of an increase in AD leakage after the activation process. We observed single photon signal timing jitter of under 450 ps in FWHM, electron transit time of {approx}12 ns, and clear pulse height separation up to several photoelectron peaks, all greatly superior to the performance of any conventional large-aperture photomultiplier tubes (PMTs). In addition, our HPD has a much simpler structure than conventional large-aperture PMTs, which simplifies mass production and lowers manufacturing cost. We believe that these attributes position our HPD as the most suitable photo-detector for the next generation mega-ton class water-Cherenkov detector, which is expected to be more than 20x larger than the Super-Kamiokande (SK) detector.

  9. Tracheostomy tubes.

    Science.gov (United States)

    Hess, Dean R; Altobelli, Neila P

    2014-06-01

    Tracheostomy tubes are used to administer positive-pressure ventilation, to provide a patent airway, and to provide access to the lower respiratory tract for airway clearance. They are available in a variety of sizes and styles from several manufacturers. The dimensions of tracheostomy tubes are given by their inner diameter, outer diameter, length, and curvature. Differences in dimensions between tubes with the same inner diameter from different manufacturers are not commonly appreciated but may have important clinical implications. Tracheostomy tubes can be cuffed or uncuffed and may be fenestrated. Some tracheostomy tubes are designed with an inner cannula. It is important for clinicians caring for patients with a tracheostomy tube to appreciate the nuances of various tracheostomy tube designs and to select a tube that appropriately fits the patient. The optimal frequency of changing a chronic tracheostomy tube is controversial. Specialized teams may be useful in managing patients with a tracheostomy. Speech can be facilitated with a speaking valve in patients with a tracheostomy tube who are breathing spontaneously. In mechanically ventilated patients with a tracheostomy, a talking tracheostomy tube, a deflated cuff technique with a speaking valve, or a deflated cuff technique without a speaking valve can be used to facilitate speech. Copyright © 2014 by Daedalus Enterprises.

  10. Characterization of photo-multiplier tubes for the Cryogenic Avalanche Detector

    CERN Document Server

    Bondar, A; Dolgov, A; Nosov, V; Shekhtman, L; Sokolov, A

    2015-01-01

    New Cryogenic Avalanche Detector (CRAD) with ultimate sensitivity, that will be able to detect one primary electron released in the cryogenic liquid, is under development in the Laboratory of Cosmology and Particle Physics of the Novosibirsk State University jointly with the Budker Institute of Nuclear Physics. The CRAD will use two sets of cryogenic PMTs in order to get trigger signal either from primary scintillations in liquid Ar or from secondary scintillations in high field gap above the liquid. Two types of cryogenic PMTs produced by Hamamatsu Photonics were tested and the results are presented in this paper. Low background 3 inch PMT R11065- 10 demonstrated excellent performance according to its specifications provided by the producer. The gain measured with single electron response (SER) in liquid Ar reached 10^7, dark count rate rate did not exceed 300 Hz and pulse height resolution of single electron signals was close to 50%(FWHM). However, two R11065-10 PMTs out of 7 tested stopped functioning afte...

  11. The Photomultiplier Tube Calibration System of the MicroBooNE Experiment

    CERN Document Server

    Conrad, J; Moss, Z; Strauss, T; Toups, M

    2015-01-01

    We report on the design and construction of an LED-based fiber calibration system for large liquid argon time projection detectors. This system was developed to calibrate the optical systems of the MicroBooNE experiment. As well as detailing the materials and installation procedure, we provide technical drawings and specifications so that the system may be easily replicated in future LArTPC detectors.

  12. Study of Various Photomultiplier Tubes with Muon Beams And Cerenkov Light Produced in Electron Showers

    CERN Document Server

    Chatrchyan, Serguei; Sirunyan, Albert M; Mossolov, Vladimir; Shumeiko, Nikolai; De Wolf, Eddi A; Ochesanu, Silvia; Roland, Benoit; Van Haevermaet, Hans; Van Mechelen, Pierre; Blyweert, Stijn; Damgov, Jordan; Dimitrov, Lubomir; Genchev, Vladimir; Piperov, Stefan; Vankov, Ivan; Roinishvili, Vladimir; Borras, Kerstin; Campbell, Alan; Jung, Hannes; Katkov, Igor; Knutsson, Albert; Sen, Niladri; Panagiotis, K; Panagiotou, Apostolos; Theodoros, M; Aranyi, Attila; Bencze, Gyorgy; Boldizsar, Laszlo; Horvath, David; Vesztergombi, Gyorgy; Bansal, Sunil; Beri, Suman Bala; Jindal, Monika; Kaur, Manjit; Kohli, Jatinder Mohan; Mehta, Manuk Zubin; Nishu, Nishu; Saini, Lovedeep Kaur; Singh, Amandeep; Singh, Jas Bir; Aziz, Tariq; Gurtu, Atul; Maity, Manas; Majumder, Devdatta; Majumder, Gobinda; Mazumdar, Kajari; Saha, Anirban; Sudhakar, Katta; Banerjee, Sunanda; Dugad, Shashikant; Mondal, Naba Kumar; Arfaei, Hessamaddin; Bakhshiansohi, Hamed; Mohammadi Najafabadi, Mojtaba; Paktinat Mehdiabadi, Saeid; Penzo, Aldo; Bunin, Pavel; Finger, Miroslav; Finger, Miroslav; Golutvin, Igor; Smirnov, Vitaly; Vishnevskiy, Alexander; Volodko, Anton; Zarubin, Anatoli; Andreev, Yuri; Kirsanov, Mikhail; Pashenkov, Anatoli; Toropin, Alexander; Troitsky, Sergey; Epshteyn, Vladimir; Gavrilov, Vladimir; Ilina, N; Kaftanov, Vitali; Kossov, Mikhail; Krokhotin, Andrey; Kuleshov, Sergey; Oulianov, Alexei; Safronov, Grigory; Semenov, Sergey; Shreyber, Irina; Stolin, Viatcheslav; Vlasov, Evgueni; Zhokin, Alexander; Demianov, A; Ershov, Alexander; Gribushin, Andrey; Klyukhin, Vyacheslav; Kodolova, Olga; Lokhtin, Igor; Obraztsov, Stepan; Petrushanko, Sergey; Proskuryakov, Alexander; Sarycheva, Ludmila; Savrin, Viktor; Vardanyan, Irina; Dremin, Igor; Kirakosyan, Martin; Konovalova, Nina; Vinogradov, Alexey; Krychkine, Victor; Petrov, Vladimir; Ryutin, Roman; Slabospitsky, Sergey; Sobol, Andrei; Sytine, Alexandre; Tourtchanovitch, Leonid; Volkov, Alexey; Adiguzel, Aytul; Bakirci, Mustafa Numan; Cerci, Salim; Dumanoglu, Isa; Eskut, Eda; Girgis, Semiray; Gurpinar, Emine; Karaman, Tugba; Kayis Topaksu, Aysel; Kurt, Pelin; Onengut, G; Ozdemir, Kadri; Ozturk, Sertac; Polatoz, A; Sogut, Kenan; Tali, Bayram; Topakli, Huseyin; Uzun, Dilber; Aliev, Takhmasib; Deniz, Muhammed; Guler, Ali Murat; Ocalan, Kadir; Serin, Meltem; Sever, Ramazan; Yildirim, Eda; Zeyrek, Mehmet; Deliomeroglu, Mehmet; Gulmez, E; Halu, Arda; Isildak, Bora; Kaya, Mithat; Kaya, Ozlem; Ozbek, M; Sonmez, Nasuf; Levchuk, Leonid; Sorokin, Pavel; Clough, Andrew; Hazen, Eric; Heering, Arjan Hendrix; Heister, Arno; John, J. St; Lawson, Philip; Lazic, Dragoslav; Rohlf, James; Sulak, Lawrence; Wu, Shouxiang; Avetisyan, Aram; Chou, John Paul; Esen, Selda; Kukartsev, Gennadiy; Landsberg, Greg; Narain, Meenakshi; Nguyen, N; Tsang, Ka Vang; Gary, J William; Liu, Feng; Nguyen, Harold; Sturdy, Jared; Winn, Dave; Banerjee, Sudeshna; Bhat, Pushpalatha C; Binkley, Morris; Chlebana, Frank; Churin, Igor; Cihangir, Selcuk; Crawford, Matt; Dagenhart, William; Demarteau, Marcel; Derylo, Greg; Dykstra, David; Eartly, David P; Elias, John E; Elvira, Victor Daniel; Freeman, Jim; Green, Dan; Hahn, Adrienne; Hanlon, Jack; Harris, Robert M; Kousouris, Konstantinos; Kunori, Shuichi; Limon, Peter; Newman-Holmes, Catherine; Sharma, Seema; Spalding, William J; Vidal, Richard; Whitmore, Juliana; Wu, Weimin; Ceron, Cristobal; Gaultney, Vanessa; Lebolo, Luis Miguel; Linn, Stephan; Markowitz, Pete; Martinez, German; Bertoldi, Maurizio; Gleyzer, Sergei V; Haas, Jeff; Hagopian, Sharon; Hagopian, Vasken; Jenkins, Merrill; Sekmen, Sezen; Baarmand, Marc M; Mermerkaya, Hamit; Ralich, Robert; Vodopiyanov, Igor; Garcia-Solis, Edmundo Javier; Akgun, Ugur; Albayrak, Elif Asli; Bilki, Burak; Cankocak, Kerem; Clarida, Warren; Duru, Firdevs; McCliment, Edward; Merlo, Jean-Pierre; Mestvirishvili, Alexi; Moeller, Anthony; Nachtman, Jane; Norbeck, Edwin; Onel, Yasar; Ozok, Ferhat; Schmidt, Ianos; Sen, Sercan; Yetkin, Taylan; Yi, Kai; Grachov, Oleg; Murray, Michael; Wood, Jeffrey Scott; Baden, Drew; Boutemeur, Madjid; Eno, Sarah Catherine; Ferencek, Dinko; Hadley, Nicholas John; Kellogg, Richard G; Kirn, Malina; Rossato, Kenneth; Rumerio, Paolo; Santanastasio, Francesco; Skuja, Andris; Temple, Jeffrey; Tonjes, Marguerite; Ton-war, S.C; Twedt, Elizabeth; Cole, Perrie; Cushman, Priscilla; Dudero, Phillip Russell; Klapoetke, Kevin; Mans, Jeremy; Cremaldi, Lucien Marcus; Godang, Romulus; Kroeger, Rob; Rahmat, Rahmat; Sanders, David A; Anastassov, Anton; Ofierzynski, Radoslaw Adrian; Pozdnyakov, Andrey; Velasco, Mayda; Won, Steven; Karmgard, Daniel John; Ruchti, Randy; Warchol, Jadwiga; Ziegler, Jill; Adam, Nadia; Berry, Edmund; Gerbaudo, Davide; Halyo, Valerie; Hunt, Adam; Jones, John; Laird, Edward; Lopes Pegna, David; Marlow, Daniel; Medvedeva, Tatiana; Mooney, Michael; Olsen, James; Tully, Christopher; Werner, Jeremy Scott; Zuranski, Andrzej; Barnes, Virgil E; Laasanen, Alvin T; Sedov, Alexey; Bodek, Arie; Chung, Yeon Sei; de Barbaro, Pawel; Garcia-Bellido, Aran; Han, Jiyeon; Harel, Amnon; Miner, Daniel Carl; Vishnevskiy, Dmitry; Zielinski, Marek; Bhatti, Anwar; Goulianos, Konstantin; Yan, Ming; Gurrola, Alfredo; Kamon, Teruki; Sengupta, Sinjini; Toback, David; Weinberger, Michael; Akchurin, Nural; Jeong, Chiyoung; Lee, Sang Joon; Popescu, Sorina; Roh, Youn; Sill, Alan; Volobouev, Igor; Wigmans, Richard; Yazgan, Efe

    2010-01-01

    The PMTs of the CMS Hadron Forward calorimeter were found to generate a large size signal when their windows were traversed by energetic charged particles. This signal, which is due to Cerenkov light production at the PMT window, could interfere with the calorimeter signal and mislead the measurements. In order to find a viable solution to this problem, the response of four different types of PMTs to muons traversing their windows at different orientations is measured at the H2 beam-line at CERN. Certain kinds of PMTs with thinner windows show significantly lower response to direct muon incidence. For the four anode PMT, a simple and powerful algorithm to identify such events and recover the PMT signal using the signals of the quadrants without window hits is also presented. For the measurement of PMT responses to Cerenkov light, the Hadron Forward calorimeter signal was mimicked by two different setups in electron beams and the PMT performances were compared with each other. Superior performance of particula...

  13. Investigating the baselines of Bismuth, Optical Fiber and LED calibrated photomultiplier tubes

    CERN Document Server

    Evans, Hywel Turner

    2016-01-01

    LUCID is a detector that is the luminosity monitor for the ATLAS experiment, and its aim is to determine luminosity with an uncertainty of a few percent. The main purpose of this work is the study of the baseline stability of the LUCID readout channels during calibration runs. This study represents the first systematic approach of this problem performed by the LUCID group. By replacing the mean baseline with the minimum baseline of each event, an upper limit of 2.85% was placed upon possible improvement in determining the LED amplitude. It is therefore better to use a fixed baseline for LED, as pollution has been observed when calculating event by event. For Bismuth and Fiber, the improvement cannot be more than the gain stability of 1%, therefore the existing method is verified as optimal.

  14. Evaluation of candidate photomultiplier tubes for the NOE scintillating fiber calorimeter

    CERN Document Server

    Barbarino, G C; Brigida, M; Campana, D; Candela, A; Caruso, R; Ceres, A; De Mitri, I; Di Credico, A; Favuzzi, C; Fusco, P; Gargano, F; Giglietto, N; Giordano, F; Grillo, A; Guarino, F; Leone, A; Lindozzi, M; Loparco, F; Mancarella, G; Mazziotta, M N; Mongelli, M; Osteria, G; Palladino, V; Perchiazzi, M; Pinto, C; Rain; Rain; Sacchetti, A; Scapparone, E; Spinelli, P; Zilli, A

    2002-01-01

    Several measurements have been made on different phototubes in order to select the type to be used for the readout system of the NOE magnetized scintillating fiber calorimeter. Characteristics such as gain, linearity, time resolution and cathode uniformity have been examined on several PMT types with standard, fine mesh or channel multiplier structure. The PMT response in the presence of the magnetized calorimeter fringe fields has also been studied. Here we report on the results of these measurements and of the comparisons between the different PMT types.

  15. Characterization of photo-multiplier tubes for the Cryogenic Avalanche Detector

    Science.gov (United States)

    Bondar, A.; Buzulutskov, A.; Dolgov, A.; Nosov, V.; Shekhtman, L.; Sokolov, A.

    2015-10-01

    New Cryogenic Avalanche Detector (CRAD) with ultimate sensitivity, that will be able to detect one primary electron released in the cryogenic liquid, is under development in the Laboratory of Cosmology and Particle Physics of the Novosibirsk State University jointly with the Budker Institute of Nuclear Physics. The CRAD will use two sets of cryogenic PMTs in order to get trigger signal either from primary scintillations in liquid Ar or from secondary scintillations in high field gap above the liquid. Two types of cryogenic PMTs produced by Hamamatsu Photonics were tested and the results are presented in this paper. Low background 3 inch PMT R11065-10 demonstrated excellent performance according to its specifications provided by the producer. The gain measured with single electron response (SER) in liquid Ar reached 107, dark count rate rate did not exceed 300 Hz and pulse height resolution of single electron signals was close to 50%(FWHM). However, two R11065-10 PMTs out of 7 tested stopped functioning after several tens minutes of operation immersed completely into liquid Ar. The remaining 5 devices and one R11065-MOD were operated successfully for several hours each with all the parameters according to the producer specifications. Compact 2 inch PMT R6041-506-MOD with metal-channel dynode structure is a candidate for side wall PMT system that will look at electroluminescence in high field region above liquid. Four of these PMTs were tested in liquid Ar and demonstrated gain up to 2× 107, dark count rate rate below 100 Hz and pulse height resolution of single electron signals of about 110% (FWHM).

  16. Muon counting using silicon photomultipliers in the AMIGA detector of the Pierre Auger observatory

    Science.gov (United States)

    Aab, A.; Abreu, P.; Aglietta, M.; Ahn, E. J.; Samarai, I. Al; Albuquerque, I. F. M.; Allekotte, I.; Allison, P.; Almela, A.; Alvarez Castillo, J.; Alvarez-Muñiz, J.; Ambrosio, M.; Anastasi, G. A.; Anchordoqui, L.; Andrada, B.; Andringa, S.; Aramo, C.; Arqueros, F.; Arsene, N.; Asorey, H.; Assis, P.; Aublin, J.; Avila, G.; Badescu, A. M.; Balaceanu, A.; Baus, C.; Beatty, J. J.; Becker, K. H.; Bellido, J. A.; Berat, C.; Bertaina, M. E.; Bertou, X.; Biermann, P. L.; Billoir, P.; Biteau, J.; Blaess, S. G.; Blanco, A.; Blazek, J.; Bleve, C.; Boháčová, M.; Boncioli, D.; Bonifazi, C.; Borodai, N.; Botti, A. M.; Brack, J.; Brancus, I.; Bretz, T.; Bridgeman, A.; Briechle, F. L.; Buchholz, P.; Bueno, A.; Buitink, S.; Buscemi, M.; Caballero-Mora, K. S.; Caccianiga, B.; Caccianiga, L.; Cancio, A.; Canfora, F.; Caramete, L.; Caruso, R.; Castellina, A.; Cataldi, G.; Cazon, L.; Cester, R.; Chavez, A. G.; Chiavassa, A.; Chinellato, J. A.; Chudoba, J.; Clay, R. W.; Colalillo, R.; Coleman, A.; Collica, L.; Coluccia, M. R.; Conceição, R.; Contreras, F.; Cooper, M. J.; Coutu, S.; Covault, C. E.; Cronin, J.; Dallier, R.; D'Amico, S.; Daniel, B.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; de Jong, S. J.; De Mauro, G.; de Mello Neto, J. R. T.; De Mitri, I.; de Oliveira, J.; de Souza, V.; Debatin, J.; del Peral, L.; Deligny, O.; Di Giulio, C.; Di Matteo, A.; Díaz Castro, M. L.; Diogo, F.; Dobrigkeit, C.; D'Olivo, J. C.; Dorofeev, A.; dos Anjos, R. C.; Dova, M. T.; Dundovic, A.; Ebr, J.; Engel, R.; Erdmann, M.; Erfani, M.; Escobar, C. O.; Espadanal, J.; Etchegoyen, A.; Falcke, H.; Fang, K.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Fick, B.; Figueira, J. M.; Filevich, A.; Filipčič, A.; Fratu, O.; Freire, M. M.; Fujii, T.; Fuster, A.; García, B.; Garcia-Pinto, D.; Gaté, F.; Gemmeke, H.; Gherghel-Lascu, A.; Ghia, P. L.; Giaccari, U.; Giammarchi, M.; Giller, M.; Głas, D.; Glaser, C.; Glass, H.; Golup, G.; Gómez Berisso, M.; Gómez Vitale, P. F.; González, N.; Gookin, B.; Gordon, J.; Gorgi, A.; Gorham, P.; Gouffon, P.; Grillo, A. F.; Grubb, T. D.; Guarino, F.; Guedes, G. P.; Hampel, M. R.; Hansen, P.; Harari, D.; Harrison, T. A.; Harton, J. L.; Hasankiadeh, Q.; Haungs, A.; Hebbeker, T.; Heck, D.; Heimann, P.; Herve, A. E.; Hill, G. C.; Hojvat, C.; Holt, E.; Homola, P.; Hörandel, J. R.; Horvath, P.; Hrabovský, M.; Huege, T.; Hulsman, J.; Insolia, A.; Isar, P. G.; Jandt, I.; Jansen, S.; Johnsen, J. A.; Josebachuili, M.; Kääpä, A.; Kambeitz, O.; Kampert, K. H.; Kasper, P.; Katkov, I.; Keilhauer, B.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Krause, R.; Krohm, N.; Kuempel, D.; Kukec Mezek, G.; Kunka, N.; Kuotb Awad, A.; LaHurd, D.; Latronico, L.; Lauscher, M.; Lebrun, P.; Legumina, R.; Leigui de Oliveira, M. A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; Lopes, L.; López, R.; López Casado, A.; Luce, Q.; Lucero, A.; Malacari, M.; Mallamaci, M.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Mariş, I. C.; Marsella, G.; Martello, D.; Martinez, H.; Martínez Bravo, O.; Masías Meza, J. J.; Mathes, H. J.; Mathys, S.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Mayotte, E.; Mazur, P. O.; Medina, C.; Medina-Tanco, G.; Melo, D.; Menshikov, A.; Messina, S.; Micheletti, M. I.; Middendorf, L.; Minaya, I. A.; Miramonti, L.; Mitrica, B.; Mockler, D.; Molina-Bueno, L.; Mollerach, S.; Montanet, F.; Morello, C.; Mostafá, M.; Müller, G.; Muller, M. A.; Müller, S.; Naranjo, I.; Navas, S.; Nellen, L.; Neuser, J.; Nguyen, P. H.; Niculescu-Oglinzanu, M.; Niechciol, M.; Niemietz, L.; Niggemann, T.; Nitz, D.; Nosek, D.; Novotny, V.; Nožka, H.; Núñez, L. A.; Ochilo, L.; Oikonomou, F.; Olinto, A.; Pakk Selmi-Dei, D.; Palatka, M.; Pallotta, J.; Papenbreer, P.; Parente, G.; Parra, A.; Paul, T.; Pech, M.; Pedreira, F.; Pȩkala, J.; Pelayo, R.; Peña-Rodriguez, J.; Pereira, L. A. S.; Perrone, L.; Peters, C.; Petrera, S.; Phuntsok, J.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.; Pirronello, V.; Platino, M.; Plum, M.; Porowski, C.; Prado, R. R.; Privitera, P.; Prouza, M.; Quel, E. J.; Querchfeld, S.; Quinn, S.; Ramos-Pollant, R.; Rautenberg, J.; Ravignani, D.; Reinert, D.; Revenu, B.; Ridky, J.; Risse, M.; Ristori, P.; Rizi, V.; Rodrigues de Carvalho, W.; Rodriguez Fernandez, G.; Rodriguez Rojo, J.; Rodríguez-Frías, M. D.; Rogozin, D.; Rosado, J.; Roth, M.; Roulet, E.; Rovero, A. C.; Saffi, S. J.; Saftoiu, A.; Salazar, H.; Saleh, A.; Salesa Greus, F.; Salina, G.; Sanabria Gomez, J. D.; Sánchez, F.; Sanchez-Lucas, P.; Santos, E. M.; Santos, E.; Sarazin, F.; Sarkar, B.; Sarmento, R.; Sarmiento-Cano, C.; Sato, R.; Scarso, C.; Schauer, M.; Scherini, V.; Schieler, H.; Schmidt, D.; Scholten, O.; Schovánek, P.; Schröder, F. G.; Schulz, A.; Schulz, J.; Schumacher, J.; Sciutto, S. J.; Segreto, A.; Settimo, M.; Shadkam, A.; Shellard, R. C.; Sigl, G.; Silli, G.; Sima, O.; Śmiałkowski, A.; Šmída, R.; Snow, G. R.; Sommers, P.; Sonntag, S.; Sorokin, J.; Squartini, R.; Stanca, D.; Stanič, S.; Stasielak, J.; Strafella, F.; Suarez, F.; Suarez Durán, M.; Sudholz, T.; Suomijärvi, T.; Supanitsky, A. D.; Sutherland, M. S.; Swain, J.; Szadkowski, Z.; Taborda, O. A.; Tapia, A.; Tepe, A.; Theodoro, V. M.; Timmermans, C.; Todero Peixoto, C. J.; Tomankova, L.; Tomé, B.; Tonachini, A.; Torralba Elipe, G.; Torres Machado, D.; Torri, M.; Travnicek, P.; Trini, M.; Ulrich, R.; Unger, M.; Urban, M.; Valbuena-Delgado, A.; Valdés Galicia, J. F.; Valiño, I.; Valore, L.; van Aar, G.; van Bodegom, P.; van den Berg, A. M.; van Vliet, A.; Varela, E.; Vargas Cárdenas, B.; Varner, G.; Vázquez, J. R.; Vázquez, R. A.; Veberič, D.; Verzi, V.; Vicha, J.; Villaseñor, L.; Vorobiov, S.; Wahlberg, H.; Wainberg, O.; Walz, D.; Watson, A. A.; Weber, M.; Weindl, A.; Wiencke, L.; Wilczyński, H.; Winchen, T.; Wittkowski, D.; Wundheiler, B.; Wykes, S.; Yang, L.; Yelos, D.; Yushkov, A.; Zas, E.; Zavrtanik, D.; Zavrtanik, M.; Zepeda, A.; Zimmermann, B.; Ziolkowski, M.; Zong, Z.; Zuccarello, F.

    2017-03-01

    AMIGA (Auger Muons and Infill for the Ground Array) is an upgrade of the Pierre Auger Observatory designed to extend its energy range of detection and to directly measure the muon content of the cosmic ray primary particle showers. The array will be formed by an infill of surface water-Cherenkov detectors associated with buried scintillation counters employed for muon counting. Each counter is composed of three scintillation modules, with a 10 m2 detection area per module. In this paper, a new generation of detectors, replacing the current multi-pixel photomultiplier tube (PMT) with silicon photo sensors (aka. SiPMs), is proposed. The selection of the new device and its front-end electronics is explained. A method to calibrate the counting system that ensures the performance of the detector is detailed. This method has the advantage of being able to be carried out in a remote place such as the one where the detectors are deployed. High efficiency results, i.e. 98% efficiency for the highest tested overvoltage, combined with a low probability of accidental counting (~2%), show a promising performance for this new system.

  17. Pulse shape discrimination using EJ-299-33 plastic scintillator coupled with a Silicon Photomultiplier array

    Science.gov (United States)

    Liao, Can; Yang, Haori

    2015-07-01

    Recent developments in organic plastic scintillators capable of pulse shape discrimination (PSD) have gained much interest. Novel photon detectors, such as Silicon Photomultipliers (SiPMs), offer numerous advantages and can be used as an alternative to conventional photo multiplier tubes (PMTs) in many applications. In this work, we evaluate the PSD performance of the EJ-299-33 plastic scintillator coupled with a SiPM array. 2D PSD plots as well as the Figure of Merit (FOM) parameters are presented to demonstrate the PSD capability of EJ-299-33 using a SiPM as the light sensor. The best FOM of 0.76 was observed with a 1.0 MeVee (MeV-electron-equivalent) energy threshold, despite the high noise level of the SiPM array. A high-speed digital oscilloscope was used to acquire data, which was then processed offline in MATLAB. A performance comparison between two different PSD algorithms was carried out. The dependence of PSD quality on the sampling rate was also evaluated, stimulated by the interest to implement this setup for handheld applications where power consumption is crucial.

  18. Experimental investigation of silicon photomultipliers as compact light readout systems for gamma-ray spectroscopy applications in fusion plasmas.

    Science.gov (United States)

    Nocente, M; Fazzi, A; Tardocchi, M; Cazzaniga, C; Lorenzoli, M; Pirovano, C; Rebai, M; Uboldi, C; Varoli, V; Gorini, G

    2014-11-01

    A matrix of Silicon Photo Multipliers has been developed for light readout from a large area 1 in. × 1 in. LaBr3 crystal. The system has been characterized in the laboratory and its performance compared to that of a conventional photo multiplier tube. A pulse duration of 100 ns was achieved, which opens up to spectroscopy applications at high counting rates. The energy resolution measured using radioactive sources extrapolates to 3%-4% in the energy range Eγ = 3-5 MeV, enabling gamma-ray spectroscopy measurements at good energy resolution. The results reported here are of relevance in view of the development of compact gamma-ray detectors with spectroscopy capabilities, such as an enhanced gamma-ray camera for high power fusion plasmas, where the use of photomultiplier is impeded by space limitation and sensitivity to magnetic fields.

  19. Experimental investigation of silicon photomultipliers as compact light readout systems for gamma-ray spectroscopy applications in fusion plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Nocente, M., E-mail: massimo.nocente@mib.infn.it; Gorini, G. [Dipartimento di Fisica “G. Occhialini,” Università degli Studi di Milano-Bicocca, Milano (Italy); Istituto di Fisica del Plasma “P. Caldirola,” EURATOM-ENEA-CNR Association, Milano (Italy); Fazzi, A.; Lorenzoli, M.; Pirovano, C. [Dipartimento di Energia, CeSNEF, Politecnico di Milano, Milano (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Milano (Italy); Tardocchi, M. [Istituto di Fisica del Plasma “P. Caldirola,” EURATOM-ENEA-CNR Association, Milano (Italy); Cazzaniga, C.; Rebai, M. [Dipartimento di Fisica “G. Occhialini,” Università degli Studi di Milano-Bicocca, Milano (Italy); Uboldi, C.; Varoli, V. [Dipartimento di Energia, CeSNEF, Politecnico di Milano, Milano (Italy)

    2014-11-15

    A matrix of Silicon Photo Multipliers has been developed for light readout from a large area 1 in. × 1 in. LaBr{sub 3} crystal. The system has been characterized in the laboratory and its performance compared to that of a conventional photo multiplier tube. A pulse duration of 100 ns was achieved, which opens up to spectroscopy applications at high counting rates. The energy resolution measured using radioactive sources extrapolates to 3%–4% in the energy range E{sub γ} = 3–5 MeV, enabling gamma-ray spectroscopy measurements at good energy resolution. The results reported here are of relevance in view of the development of compact gamma-ray detectors with spectroscopy capabilities, such as an enhanced gamma-ray camera for high power fusion plasmas, where the use of photomultiplier is impeded by space limitation and sensitivity to magnetic fields.

  20. Characterization of Three High Efficiency and Blue Sensitive Silicon Photomultipliers

    CERN Document Server

    Otte, Adam Nepomuk; Nguyen, Thanh; Purushotham, Dhruv

    2016-01-01

    We report about the optical and electrical characterization of three high efficiency and blue sensitive Silicon photomultipliers from FBK, Hamamatsu, and SensL. Key features of the tested devices when operated at 90% breakdown probability are peak photon detection efficiencies between 40% and 55%, temperature dependencies of gain and PDE that are less than 1%/$^{\\circ}$C, dark rates of $\\sim$50\\,kHz/mm$^{2}$ at room temperature, afterpulsing of about 2%, and direct optical crosstalk between 6% and 20%. The characteristics of all three devices impressively demonstrate how the Silicon-photomultiplier technology has improved over the past ten years. It is further demonstrated how the voltage and temperature characteristics of a number of quantities can be parameterized on the basis of physical models. The models provide a deeper understanding of the device characteristics over a wide bias and temperature range. They also serve as examples how producers could provide the characteristics of their SiPMs to users. A...

  1. Characterization of three high efficiency and blue sensitive silicon photomultipliers

    Science.gov (United States)

    Otte, Adam Nepomuk; Garcia, Distefano; Nguyen, Thanh; Purushotham, Dhruv

    2017-02-01

    We report about the optical and electrical characterization of three high efficiency and blue sensitive Silicon photomultipliers from FBK, Hamamatsu, and SensL. Key features of the tested devices when operated at 90% breakdown probability are peak photon detection efficiencies between 40% and 55%, temperature dependencies of gain and PDE that are less than 1%/°C, dark rates of ∼50 kHz/mm2 at room temperature, afterpulsing of about 2%, and direct optical crosstalk between 6% and 20%. The characteristics of all three devices impressively demonstrate how the Silicon-photomultiplier technology has improved over the past ten years. It is further demonstrated how the voltage and temperature characteristics of a number of quantities can be parameterized on the basis of physical models. The models provide a deeper understanding of the device characteristics over a wide bias and temperature range. They also serve as examples how producers could provide the characteristics of their SiPMs to users. A standardized parameterization of SiPMs would enable users to find the optimal SiPM for their application and the operating point of SiPMs without having to perform measurements thus significantly reducing design and development cycles.

  2. Time resolution of a photomultiplier readout system for space application

    CERN Document Server

    Commichau, Sebastian Caspar; Capell, M; Commichau, Volker; Flügge, G; Hangarter, K; Lebedev, A; Mnich, J; Röser, U; Viertel, G M; Von Gunten, H P

    2004-01-01

    The performance of a readout system for the synchrotron radiation detector (SRD) is studied. The detector is proposed as part of the Alpha Magnetic Spectrometer experiment, an experiment to fly on the International Space Station (ISS) beginning of 2005. The SRD is designed to detect the synchrotron radiation from electrons and positrons (TeV energy range) produced in the earth's magnetic field. For the planned array of scintillators and photomultipliers a readout system is chosen, which is compact, space qualified and has a low- power consumption. The low-power chip APV, originally designed for the CMS experiment at LHC (CERN), is foreseen for the readout. To overcome the diffuse background from photons and charged particles the SRD readout must have a time resolution better than 10 ns. The intrinsic time resolution (sigma from Gauss fit) of the APV25-S0 was found to be 0.46 +or- 0.01 and 0.68 +or-0.02 ns for the APVM. whereas the time resolution of the photomultiplier-APV readout system was measured to be 2....

  3. Cherenkov luminescence measurements with digital silicon photomultipliers: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Ciarrocchi, Esther; Belcari, Nicola; Guerra, Alberto Del [Department of Physics, University of Pisa, Pisa (Italy); INFN, section of Pisa, Pisa (Italy); Cherry, Simon R. [Department of Biomedical Engineering, University of California, Davis, CA (United States); Lehnert, Adrienne; Hunter, William C. J.; McDougald, Wendy; Miyaoka, Robert S.; Kinahan, Paul E. [Department of Radiology, University of Washington, Seattle, WA (United States)

    2015-11-16

    A feasibility study was done to assess the capability of digital silicon photomultipliers to measure the Cherenkov luminescence emitted by a β source. Cherenkov luminescence imaging (CLI) is possible with a charge coupled device (CCD) based technology, but a stand-alone technique for quantitative activity measurements based on Cherenkov luminescence has not yet been developed. Silicon photomultipliers (SiPMs) are photon counting devices with a fast impulse response and can potentially be used to quantify β-emitting radiotracer distributions by CLI. In this study, a Philips digital photon counting (PDPC) silicon photomultiplier detector was evaluated for measuring Cherenkov luminescence. The PDPC detector is a matrix of avalanche photodiodes, which were read one at a time in a dark count map (DCM) measurement mode (much like a CCD). This reduces the device active area but allows the information from a single avalanche photodiode to be preserved, which is not possible with analog SiPMs. An algorithm to reject the noisiest photodiodes and to correct the measured count rate for the dark current was developed. The results show that, in DCM mode and at (10–13) °C, the PDPC has a dynamic response to different levels of Cherenkov luminescence emitted by a β source and transmitted through an opaque medium. This suggests the potential for this approach to provide quantitative activity measurements. Interestingly, the potential use of the PDPC in DCM mode for direct imaging of Cherenkov luminescence, as a opposed to a scalar measurement device, was also apparent. We showed that a PDPC tile in DCM mode is able to detect and image a β source through its Cherenkov radiation emission. The detector’s dynamic response to different levels of radiation suggests its potential quantitative capabilities, and the DCM mode allows imaging with a better spatial resolution than the conventional event-triggered mode. Finally, the same acquisition procedure and data processing could

  4. Performance of Scintillator Counters with Silicon Photomultiplier Readout

    CERN Document Server

    Artikov, A; Chokheli, D; Davydov, Yu I; Dukes, E C; Ehrlich, R; Francis, K; Frank, M J; Glagolev, V; Hansen, S; Hocker, A; Oksuzian, Y; Rubinov, P; Song, E; Uzunyan, S; Wu, Y

    2015-01-01

    The performance of scintillator counters with embedded wavelength-shifting fibers has been measured in the Fermilab Meson Test Beam Facility using 120 GeV protons. The counters were extruded with a titanium dioxide surface coating and two channels for fibers at the Fermilab NICADD facility. Each fiber end is read out by a 2*2 mm^2 silicon photomultiplier. The signals were amplified and digitized by a custom-made front-end electronics board. Combinations of 5*2 cm^2 and 6*2 cm^2 extrusion profiles with 1.4 and 1.8 mm diameter fibers were tested. The design is intended for the cosmic-ray veto detector for the Mu2e experiment at Fermilab. The light yield as a function of the transverse and longitudinal position of the beam will be given.

  5. Precise method for determining avalanche breakdown voltage of silicon photomultipliers

    Science.gov (United States)

    Chirikov-Zorin, I.

    2017-07-01

    A physically motivated method is proposed for determining the avalanche breakdown voltage of silicon photomultipliers (SiPM). The method is based on measuring the dependence of the relative photon detection efficiency (PDErel) on the bias voltage when one type of carriers (electron or hole) is injected into the avalanche multiplication zone of the p-n junction. The injection of electrons or holes from the base region of the SiPM semiconductor structure is performed using short-wave or long-wave light. At a low overvoltage (1-2 V) the detection efficiency is linearly dependent on the bias voltage; therefore, extrapolation to zero PDErel value determines the SiPM avalanche breakdown voltage with an accuracy within a few millivolts.

  6. Timing optimization utilizing order statistics and multichannel digital silicon photomultipliers.

    Science.gov (United States)

    Mandai, Shingo; Venialgo, Esteban; Charbon, Edoardo

    2014-02-01

    We present an optimization technique utilizing order statistics with a multichannel digital silicon photomultiplier (MD-SiPM) for timing measurements. Accurate timing measurements are required by 3D rangefinding and time-of-flight positron emission tomography, to name a few applications. We have demonstrated the ability of the MD-SiPM to detect multiple photons, and we verified the advantage of detecting multiple photons assuming incoming photons follow a Gaussian distribution. We have also shown the advantage of utilizing multiple timestamps for estimating time-of-arrivals more accurately. This estimation technique can be widely available in various applications, which have a certain probability density function of incoming photons, such as a scintillator or a laser source.

  7. A study of timing properties of Silicon Photomultipliers

    Science.gov (United States)

    Avella, Paola; De Santo, Antonella; Lohstroh, Annika; Sajjad, Muhammad T.; Sellin, Paul J.

    2012-12-01

    Silicon Photomultipliers (SiPMs) are solid-state pixelated photodetectors. Lately these sensors have been investigated for Time of Flight Positron Emission Tomography (ToF-PET) applications, where very good coincidence time resolution of the order of hundreds of picoseconds imply spatial resolution of the order of cm in the image reconstruction. The very fast rise time typical of the avalanche discharge improves the time resolution, but can be limited by the readout electronics and the technology used to construct the device. In this work the parameters of the equivalent circuit of the device that directly affect the pulse shape, namely the quenching resistance and capacitance and the diode and parasitic capacitances, were calculated. The mean rise time obtained with different preamplifiers was also measured.

  8. Silicon Photomultipliers in High Energy and Space Applications

    CERN Document Server

    Berra, Alessandro; Vallazza, Erik

    In recent years Silicon Photomultipliers (SiPMs) have been proposed as a new type of readout system for scintillating detectors in many experiments. SiPMs consist of a matrix of parallel-connected silicon micro-pixels, which are independent photon counters working in limited Geiger mode with very high gain. The goal of this thesis work is to describe the use of SiPMs as a readout system for plastic scintillators, both for tracking and calorimetry purposes. Different prototypes of scintillating bar tracker and shashlik calorimeters have been tested at CERN on the PS and SPS extracted beamlines. All the tests have been performed in the framework of the FACTOR (Fiber Apparatus for Calorimetry and Tracking with Optoelectronic Read-out) collaboration, a three year R&D project started in 2007 and funded by the Italian Institute of Nuclear Physics (INFN).

  9. Use of Silicon Photomultiplier in LBL Cosmic Tay Detector

    Science.gov (United States)

    Osornio, Leo

    2012-10-01

    During a summer internship program at Hartnell Community College our team successfully constructed two complementary cosmic ray experiments. The first employed NIM electronic modules the second constructed as per specifications of a circuit board designed by the Berkeley Lab Cosmic Ray Telescope Project (http://cosmic.lbl.gov/). During the following summer at Lawrence Berkeley National Laboratory, we worked on optimizing the performance of a group of Berkeley Lab Detector and developed tools to measure its performance. The next phase was exploring whether Silicon Photomultiplier (SiPM) can be used to replace the phototube of the Berkeley Detector. Data will be presented from both summers including the dependence of the cosmic ray flux on the separation and polar angle of scintillator paddles, as well as the results from our SiPM tests. Finally, I will include prospects for curriculum development using the cosmic ray experiments.

  10. The upgrade of the CMS hadron calorimeter with silicon photomultipliers

    Science.gov (United States)

    Strobbe, N.

    2017-01-01

    The upgrade of the hadron calorimeter of the CMS experiment at the CERN Large Hadron Collider is currently underway. The endcap sections will be upgraded in the winter of 2016-2017 and the barrel sections during the second LHC long shutdown in 2019. The existing photosensors will be replaced with about 16 000 new silicon photomultipliers (SiPMs), resulting in the first large installation of SiPMs in a radiation environment. All associated front-end electronics will also be upgraded. This paper discusses the motivation for the upgrade and provides a description of the new system, including the SiPMs with associated control electronics and the front-end readout cards.

  11. Study of silicon photomultipliers fast amplifier and thermoregulation

    Energy Technology Data Exchange (ETDEWEB)

    D' antone, I. [INFN of Bologna, Viale B.Pichat 4/2, 40127 Bologna (Italy); Fabbri, L.; Foschi, E. [Department of Physics and INFN, Viale B.Pichat 4/2, 40127 Bologna (Italy); Guandalini, C.; Laurenti, G.; Lax, I. [INFN of Bologna, Viale B.Pichat 4/2, 40127 Bologna (Italy); Levi, G.; Quadrani, L.; Sbarra, Ca. [Department of Physics and INFN, Viale B.Pichat 4/2, 40127 Bologna (Italy); Sbarra, Cr., E-mail: cristina.sbarra@bo.infn.i [Department of Physics and INFN, Viale B.Pichat 4/2, 40127 Bologna (Italy); Villa, M.; Zoccoli, A. [Department of Physics and INFN, Viale B.Pichat 4/2, 40127 Bologna (Italy); Zuffa, M. [INFN of Bologna, Viale B.Pichat 4/2, 40127 Bologna (Italy)

    2011-02-21

    The silicon photomultipliers (SiPM) are adopted in various physical applications, from medical physics to astrophysics, for their advantages in terms of cost and weight with respect to traditional photo detectors. Their low bias voltage supply (about 30 V), hardiness and resistance to magnetic field are ideal characteristics for space application. In the frame of INFN-Irst collaboration, some of them have been developed and produced at FBK (Trento-Italy), and have been characterized in the INFN laboratories of Bologna (DaSiPM2 collaboration). The SiPM can be used in conjunction with fibres and counters in high energy physics experiments. To exploit the SiPM time resolution, a fast amplifier has been studied. The SiPM gain depends critically on temperature and a thermal stabilization is also necessary. The use of a thermoelectric cooler module based on a Peltier cell has been investigated, and the results are shown.

  12. Silicon Photomultiplier Camera for Schwarzschild-Couder Cherenkov Telescopes

    CERN Document Server

    Vandenbroucke, J

    2014-01-01

    The Cherenkov Telescope Array (CTA) is an atmospheric Cherenkov observatory that will image the cosmos in very-high-energy gamma rays. CTA will study the highest-energy particle accelerators in the Universe and potentially confirm the particle nature of dark matter. We have designed an innovative Schwarzschild-Couder telescope which uses two mirrors to achieve excellent optical performance across a wide field of view. The small plate scale of the dual-mirror optics enables a compact camera which uses modern technology including silicon photomultipliers and the TARGET application-specific integrated circuit to read out a finely pixelated focal plane of 11,328 channels with modest weight, volume, cost, and power consumption. The camera design is hierarchical and modular at each level, enabling robust construction, operation, and maintenance. A prototype telescope is under construction and will be commissioned at the VERITAS site in Arizona. An array of such telescopes will provide excellent angular resolution a...

  13. Gated Microchannel Plate Photomultiplier For Longitudinal BeamDiagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Byrd, John M.; De Santis, Stefano; Thurman-Keup, Randy

    2006-05-03

    A gated microchannel plate photomultiplier can be used as aneffective tool for measuring the longitudinal distribution of particlesaround most electron and high-energy proton rings. The broad availablewavelength range,low noise, and high sensitivity allow using such adevice for measuring the emitted synchrotron radiation and to extract thebeam intensity. The fast gate rise time can be used to reject strongsignals coming from filled RF buckets and avoid saturation of thephotocathode so that it is possible to monitor, with a high degree ofresolution, gaps in the machine fill and growth of parasitic bunches. Therugged characteristics of the device and its simplicity of use make itideal for all those applications where more complex and expensiveinstrumentation is not absolutely necessary. We present the experimentalresults obtained at the Advanced Light Source and on the Tevatron usingan Hamamatsu R5916U-50 series model.

  14. 聚酰亚胺/碳纳米管杂化薄膜电性能的研究%Electrical Properties of Polyimide/Carbon Nano-tube Hybrid Film

    Institute of Scientific and Technical Information of China (English)

    朱小影; 张明艳; 刁鹏鹤; 王文佳; 李晓东

    2011-01-01

    A kind of polyamide acid/carbon nano-tube hybrid liquid cement was fabricated by means of ultrasonic dispersion and in-situ polymerization.Then the polyimide/carbon nano-tube hybrid film was prepared according to filming technology.The surface morphology of the film was characterized by SEM.And the effects of incorporation of carbon nano-tube on the electrical property were researched.The results show that with the increase of CNTs content, the dielectric strength decreases gradually and has a sharp drop when the doped content is close to 0.6%, the dielectric constant and dielectric loss factor increase obviously.With the rise of test frequency, the dielectric constant declines slowly and the dielectric loss factor increases.The corona resistance time of the hybrid film is longer than that of pure polyimide.When the doped content of MWNTs is near to 0.38%, the time of corona resistance reaches a maximum of 10.2 h.%采用超声分散-原位聚合的方法制备聚酰胺酸/碳纳米管(CNTs)杂化胶液,并按一定成膜工艺制备出聚酰亚胺/碳纳米管杂化薄膜.利用扫描电子显微镜(SEM)对薄膜的表面形貌进行表征,讨论了碳纳米管的加入对杂化薄膜电性能的影响.结果表明:随着碳纳米管含量的增加,介电强度降低,介电常数与介质损耗因数均呈上升趋势,且随着测试频率的增加,介电常数缓慢下降,介质损耗因数增加;杂化薄膜的耐电晕性能均高于纯PI,且含量为0.38%时,耐电晕时间达到最大值10.2h.

  15. Sol-gel approach to in situ creation of high pH-resistant surface-bonded organic-inorganic hybrid zirconia coating for capillary microextraction (in-tube SPME).

    Science.gov (United States)

    Alhooshani, Khalid; Kim, Tae-Young; Kabir, Abuzar; Malik, Abdul

    2005-01-07

    A novel zirconia-based hybrid organic-inorganic sol-gel coating was developed for capillary microextraction (CME) (in-tube SPME). High degree of chemical inertness inherent in zirconia makes it very difficult to covalently bind a suitable organic ligand to its surface. In the present work, this problem was addressed from a sol-gel chemistry point of view. Principles of sol-gel chemistry were employed to chemically bind a hydroxy-terminated silicone polymer (polydimethyldiphenylsiloxane, PDMDPS) to a sol-gel zirconia network in the course of its evolution from a highly reactive alkoxide precursor undergoing controlled hydrolytic polycondensation reactions. A fused silica capillary was filled with a properly designed sol solution to allow for the sol-gel reactions to take place within the capillary for a predetermined period of time (typically 15-30 min). In the course of this process, a layer of the evolving hybrid organic-inorganic sol-gel polymer got chemically anchored to the silanol groups on the capillary inner walls via condensation reaction. At the end of this in-capillary residence time, the unbonded part of the sol solution was expelled from the capillary under helium pressure, leaving behind a chemically bonded sol-gel zirconia-PDMDPS coating on the inner walls. Polycyclic aromatic hydrocarbons, ketones, and aldehydes were efficiently extracted and preconcentrated from dilute aqueous samples using sol-gel zirconia-PDMDPS coated capillaries followed by thermal desorption and GC analysis of the extracted solutes. The newly developed sol-gel hybrid zirconia coatings demonstrated excellent pH stability, and retained the extraction characteristics intact even after continuous rinsing with a 0.1 M NaOH solution for 24 h. To our knowledge, this is the first report on the use of a sol-gel zirconia-based hybrid organic-inorganic coating as an extraction medium in solid phase microextraction (SPME).

  16. Procedures and results of the measurements on large area photomultipliers for the NEMO project

    Science.gov (United States)

    Aiello, S.; Leonora, E.; Aloisio, A.; Ameli, F.; Amore, I.; Anghinolfi, M.; Anzalone, A.; Barbarino, G.; Barbarito, E.; Battaglieri, M.; Bazzotti, M.; Bellotti, R.; Bersani, A.; Beverini, N.; Biagi, S.; Bonori, M.; Bouhdaef, B.; Cacopardo, G.; Calı, C.; Capone, A.; Caponetto, L.; Carminati, G.; Cassano, B.; Ceres, A.; Chiarusi, T.; Circella, M.; Cocimano, R.; Coniglione, R.; Cordelli, M.; Costa, M.; D'Amico, A.; DeBonis, G.; DeRosa, G.; DeRuvo, G.; DeVita, R.; Distefano, C.; Flaminio, V.; Fratini, K.; Gabrielli, A.; Galeotti, S.; Gandolfi, E.; Giacomelli, G.; Giorgi, F.; Giovanetti, G.; Grimaldi, A.; Grmek, A.; Habel, R.; Imbesi, M.; Lonardo, A.; LoPresti, D.; Lucarelli, F.; Margiotta, A.; Marinelli, A.; Martini, A.; Masullo, R.; Maugeri, F.; Migneco, E.; Minutoli, S.; Mongelli, M.; Morganti, M.; Musico, P.; Musumeci, M.; Orlando, A.; Osipenko, M.; Papaleo, R.; Pappalardo, V.; Piattelli, P.; Piombo, D.; Raffaelli, F.; Raia, G.; Randazzo, N.; Reito, S.; Ricco, G.; Riccobene, G.; Ripani, M.; Rovelli, A.; Ruppi, M.; Russo, G. V.; Russo, S.; Sapienza, P.; Sedita, M.; Shirokov, E.; Simeone, F.; Sciliberto, D.; Sipala, V.; Sollima, C.; Spurio, M.; Stefani, F.; Taiuti, M.; Terreni, G.; Trasatti, L.; Urso, S.; Vecchi, M.; Vicini, P.; Wischnewski, R.

    2010-03-01

    The selection of the photomultiplier plays a crucial role in the R&D activity related to a large-scale underwater neutrino telescope. This paper illustrates the main procedures and facilities used to characterize the performances of 72 large area photomultipliers, Hamamatsu model R7081 sel. The voltage to achieve a gain of 5×10 7, dark count rate and single photoelectron time and charge properties of the overall response were measured with a properly attenuated 410 nm pulsed laser. A dedicated study of the spurious pulses was also performed. The results prove that the photomultipliers comply with the general requirements imposed by the project.

  17. Photomultiplier nonlinear response in time-domain laser-induced luminescence spectroscopy

    Directory of Open Access Journals (Sweden)

    Leandro José Bossy Schip

    2007-02-01

    Full Text Available A new procedure to find the limiting range of the photomultiplier linear response of a low-cost, digital oscilloscope-based time-resolved laser-induced luminescence spectrometer (TRLS, is presented. A systematic investigation on the instrument response function with different signal input terminations, and the relationship between the luminescence intensity reaching the photomultiplier and the measured decay time are described. These investigations establish that setting the maximum intensity of the luminescence signal below 0.3V guarantees, for signal input terminations equal or higher than 99.7 ohm, a linear photomultiplier response.

  18. An innovative silicon photomultiplier digitizing camera for gamma-ray astronomy

    National Research Council Canada - National Science Library

    Heller, M; Schioppa, E jr; Porcelli, A; Pujadas, I Troyano; Ziȩtara, K; Volpe, D della; Montaruli, T; Cadoux, F; Favre, Y; Aguilar, J A; Christov, A; Prandini, E; Rajda, P; Rameez, M; Bilnik, W; Błocki, J; Bogacz, L; Borkowski, J; Bulik, T; Frankowski, A; Grudzińska, M; Idźkowski, B; Jamrozy, M; Janiak, M; Kasperek, J; Lalik, K; Lyard, E; Mach, E; Mandat, D; Marszałek, A; Miranda, L D. Medina; Michałowski, J; Moderski, R; Neronov, A; Niemiec, J; Ostrowski, M; Paśko, P; Pech, M; Schovanek, P; Seweryn, K; Sliusar, V; Skowron, K; Stawarz, Ł; Stodulska, M; Stodulski, M; Walter, R; Wiȩcek, M; Zagdański, A

    2017-01-01

    ...) of the Cherenkov Telescope Array (CTA) project. The SST-1M will be equipped with a 4 m-diameter segmented reflector dish and an innovative fully digital camera based on silicon photo-multipliers...

  19. Gastrostomy Tube (G-Tube)

    Science.gov (United States)

    ... the recovery room, sometimes called the "post-op" (post-operative) room or PACU (post-anesthesia care unit), and ... site; discharge that's yellow, green, or foul-smelling; fever) excessive bleeding or drainage from the tube site ...

  20. Study the performance of LYSO and CeBr3 crystals using Silicon Photomultipliers

    Science.gov (United States)

    Kryemadhi, Abaz

    2016-03-01

    The Silicon Photomultipliers (SiPMs) are novel photon-detectors which have been progressively found their use in particle physics. Their small size, good single photon resolution, simple readout, and immunity to magnetic fields offers advantages compared to traditional photomultipliers. LYSO and CeBr3 crystals are relatively new scintillators with high light yield and fast decay time. The response of these detectors to low energy gamma rays and cosmic ray muons will be presented. Messiah College Workload Reallocation Program.

  1. Application of ultrashort laser pulses for timing characterization of silicon photomultipliers

    Science.gov (United States)

    Popova, E. V.; Buzhan, P. Zh; Stifutkin, A. A.; Ilyin, A. L.; Mavritskii, O. B.; Egorov, A. N.; Nastulyavichius, A. A.

    2016-08-01

    The application of femtosecond laser irradiation for the investigation of Geiger discharge process in silicon photomultiplier (SiPM) is discussed. It is shown experimentally that sub-picosecond pulses of laser beam focused to micron spot sizes allow studying the dynamics of Geiger discharge process in single cell of silicon photomultiplier. These studies are aimed at identifying the factors limiting the timing resolution of this class of devices.

  2. Characterization of Silicon Photomultiplier Detectors using Cosmic Radiation

    Science.gov (United States)

    Zavala, Favian; Castro, Juan; Niduaza, Rexavalmar; Wedel, Zachary; Fan, Sewan; Ritt, Stefan; Fatuzzo, Laura

    2014-03-01

    The silicon photomultiplier light detector has gained a lot of attention lately in fields such as particle physics, astrophysics, and medical physics. Its popularity stems from its lower cost, compact size, insensitivity to magnetic fields, and its excellent ability to distinguish a quantized number of photons. They are normally operated at room temperature and biased above their breakdown voltages. As such, they may also exhibit properties that may hinder their optimal operation which include a thermally induced high dark count rate, after pulse effects, and cross talk from photons in nearby pixels. At this poster session, we describe our data analysis and our endeavor to characterize the multipixel photon counter (MPPC) detectors from Hamamatsu under different bias voltages and temperature conditions. Particularly, we describe our setup which uses cosmic rays to induce scintillation light delivered to the detector by wavelength shifting optical fibers and the use of a fast 1 GHz waveform sampler, the domino ring sampler (DRS4) digitizer board. Department of Education grant number P031S90007.

  3. A new instrument for high statistics measurement of photomultiplier characteristics

    CERN Document Server

    Bozza, C; Costa, M; Di Capua, F; Kulikovskiy, V; Mele, R; Migliozzi, P; Mollo, C M; Pellegrino, C; Riccobene, G; Vivolo, D

    2016-01-01

    Since the early days of experimental particle physics photomultipliers (PMTs) have played an important role in the detector design. Thanks to their capability of fast photon counting, PMTs are extensively used in the new-generation of astroparticle physics experiments, such as air, ice and water Cherenkov detectors. The use of PMTs of 3-inches or smaller diameter was made possible thanks to the capability of building detectors with large photocathode area distributed in a sustainable number of channels. Small size PMTs ($\\leq$ 3-inches) show little sensitivity to the Earth magnetic field, small transit time, stable transit time spread; the price per photocathode area is less comparing to the one for the large area PMTs, typically used so far in such applications. In this paper we report on the design and performance of a new instrument for mass characterisation of PMTs (from 1-inch to 3-inch size), capable to calibrate hundreds of PMTs per day and provide measurements of dark counts, signal amplitude, late-, ...

  4. Characterization of Silicon Photomultipliers for nEXO

    CERN Document Server

    Ostrovskiy, I; Auty, D; Dalmasson, J; Didberidze, T; DeVoe, R; Gratta, G; Huth, L; James, L; Lupin-Jimenez, L; Ohmert, N; Piepke, A

    2015-01-01

    Silicon Photomultipliers (SiPMs) are attractive candidates for light detectors for next generation liquid xenon double-beta decay experiments, like nEXO. In this paper we discuss the requirements that the SiPMs must satisfy in order to be suitable for nEXO and similar experiments, describe the two test setups operated by the nEXO collaboration, and present the results of characterization of SiPMs from several vendors. In particular, we find that the photon detection efficiency at the peak of xenon scintillation light emission (175-178 nm) approaches (exceeds) the nEXO requirements for tested FBK (Hamamatsu) devices. Additionally, the nEXO collaboration performed radioassay of several grams of bare FBK devices using neutron activation analysis, indicating levels of 40K, 232Th, and 238U of the order of <0.15, (6.9e10-4 - 1.3e10-2), and <0.11 mBq/kg, respectively.

  5. An instrument for measuring scintillators efficiently based on silicon photomultipliers.

    Science.gov (United States)

    Yang, M J; Zhang, Z M; Wang, Y J; Li, D W; Zhou, W; Tang, H H; Liu, Y T; Chai, P; Shuai, L; Huang, X C; Liu, S Q; Zhu, M L; Jiang, X P; Zhang, Y W; Li, T; Ma, B; Sun, S F; Sun, L Y; Wang, Q; Lu, Z R; Zhang, T; Wei, L

    2016-11-01

    An instrument used for measuring multiple scintillators' light output and energy resolution was developed. The instrument consisted of a light sensor array which was composed of 64 discrete SiPMs (Silicon Photomultipliers), a corresponding individual channel readout electronics system, and a data processing algorithm. A Teflon grid and a large interval between adjacent SiPMs were employed to eliminate the optical cross talk among scintillators. The scintillators' light output was obtained by comparing with a reference sample with known light output. Given the SiPM temperature dependency and the difference among each SiPM, a temperature offset correction algorithm and a non-uniformity correction algorithm were added to the instrument. A positioning algorithm, based on nine points, was designed to evaluate the performance of a scintillator array. Tests were performed to evaluate the instrument's performance. The uniformity of 64 channels for light output measurement was better than 98%, the stability was better than 98% when temperature varied from 15 °C to 40 °C, and the nonlinearity under 511 keV was better than 2%. This instrument was capable of selecting scintillators and evaluating the packaging technology of scintillator arrays with high efficiency and accuracy.

  6. Study of the radiation damage of silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Nitschke, Michael; Chmill, Valery; Garutti, Erika; Klanner, Robert; Schwandt, Joern [Institute for Experimental Physics, Hamburg University, Luruper Chaussee 149, D-22761 Hamburg (Germany)

    2016-07-01

    Radiation damage significantly changes the performance of silicon photomultipliers (SiPM). In this work, we first have characterized KETEK SiPMs with a pixel size of 15 x 15 μm{sup 2} using I-V (current-voltage), C/G-V/f (capacitance/impedance-voltage/frequency) and Q-V (charge-voltage) measurements with and without illumination with blue light of 470 nm from an LED. The SiPM parameters determined are DCR (dark count rate), relative PDE (photon detection efficiency), G (Gain), XT (cross-talk), Geiger breakdown characteristics, C{sub pix} (pixel capacitance) and R{sub q} (quenching resistance). Following this first characterization, the SiPMs were irradiated using reactor neutrons with fluences of 10{sup 9}, 10{sup 10}, 10{sup 11}, 5 . 10{sup 11}, and 10{sup 12} n/cm{sup 2}. Afterwards, the same measurements were repeated, and the dependence of the SiPM parameters on neutron fluence was determined. The results are used to optimize the radiation tolerance of SiPMs.

  7. Dark noise rates in irradiated silicon photomultiplier arrays

    Energy Technology Data Exchange (ETDEWEB)

    Bachmann, Sebastian; Comerma, Albert; Gerick, David; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Kecke, Matthieu; Leverington, Blake; Mazorra de Cos, Jose; Mitzel, Dominik; Neuner, Max; Uwer, Ulrich [Physikalisches Institut, Universitaet Heidelberg (Germany); Collaboration: LHCb-Collaboration

    2016-07-01

    The planned downstream tracking system - the Scintillating Fibre Tracker - for the LHCb upgrade uses silicon photomultiplier (SiPM) arrays of 128 channels to read out mats made of 250 μm diameter scintillating fibres. In the LHCb environment the neutron flux degrades the silicon detectors to the edge of an acceptable performance in terms of DCR. Studies have shown that the dark count rate (DCR) of the SiPMs increases linearly with the neutron flux. Towards the end of the designed lifetime of the experiment the DCR per SiPM channel operated at T = -40 C is expected to reach a few MHz after partial annealing. To reduce the impact of the DCR - while at the same time provide efficient hit reconstruction - a clustering algorithm is developed to separate signal from noise. A brief introduction into the custom designed read-out ASIC and the cluster algorithm are presented along with the studies of the dark count cluster rate dependency on the neutron flux, the DCR per channel and the effects of the applied signal thresholds for the clustering algorithm.

  8. Silicon photomultipliers. Properties and applications in a highly granular calorimeter

    Energy Technology Data Exchange (ETDEWEB)

    Feege, Nils

    2008-12-15

    Silicon Photomultipliers (SiPMs) are novel semiconductor-based photodetectors operated in Geiger mode. Their response is not linear, and both their gain and their photon detection efficiency depend on the applied bias voltage and on temperature. The CALICE collaboration investigates several technology options for highly granular calorimeters for the future ILC. The prototype of a scintillator-steel sampling calorimeter with analogue readout for hadrons constructed at DESY and successfully operated in testbeam experiments at DESY, CERN and FNAL by this collaboration is the first large scale application for 7608 SiPMs developed by MEPhI. This thesis deals with properties of the SiPMs used in the calorimeter prototype. The effective numer of pixels of the SiPMs, which influences their saturation behaviour, is extracted from in situ measurements and compared to results obtained for the bare SiPMs. In addition, the effects of temperature and voltage changes on the parameters necessary for the calibration of the SiPMs and the detector are determined. Methods which allow for correcting or compensating these effects are evaluated. An approach to improve the absolute calibration of the temperature sensors in the prototype is described and temperature profiles are studied. Finally, a procedure to adjust the light yield of the cells of the prototype is presented. The results of the application of this procedure during the commissioning of the detector at FNAL are discussed. (orig.)

  9. An instrument for measuring scintillators efficiently based on silicon photomultipliers

    Science.gov (United States)

    Yang, M. J.; Zhang, Z. M.; Wang, Y. J.; Li, D. W.; Zhou, W.; Tang, H. H.; Liu, Y. T.; Chai, P.; Shuai, L.; Huang, X. C.; Liu, S. Q.; Zhu, M. L.; Jiang, X. P.; Zhang, Y. W.; Li, T.; Ma, B.; Sun, S. F.; Sun, L. Y.; Wang, Q.; Lu, Z. R.; Zhang, T.; Wei, L.

    2016-11-01

    An instrument used for measuring multiple scintillators' light output and energy resolution was developed. The instrument consisted of a light sensor array which was composed of 64 discrete SiPMs (Silicon Photomultipliers), a corresponding individual channel readout electronics system, and a data processing algorithm. A Teflon grid and a large interval between adjacent SiPMs were employed to eliminate the optical cross talk among scintillators. The scintillators' light output was obtained by comparing with a reference sample with known light output. Given the SiPM temperature dependency and the difference among each SiPM, a temperature offset correction algorithm and a non-uniformity correction algorithm were added to the instrument. A positioning algorithm, based on nine points, was designed to evaluate the performance of a scintillator array. Tests were performed to evaluate the instrument's performance. The uniformity of 64 channels for light output measurement was better than 98%, the stability was better than 98% when temperature varied from 15 °C to 40 °C, and the nonlinearity under 511 keV was better than 2%. This instrument was capable of selecting scintillators and evaluating the packaging technology of scintillator arrays with high efficiency and accuracy.

  10. Evaluation of performance of silicon photomultipliers in lidar applications

    Science.gov (United States)

    Vinogradov, Sergey L.

    2017-05-01

    Silicon Photomultipliers (SiPMs) are a well-recognized new generation of photon number resolving avalanche photodetectors. Many advantages - a high gain with an ultra-low excess noise of multiplication, multi-pixel architecture, relatively low operating voltage - make SiPMs very competitive in a growing number of applications. Challenging demands of LIDAR applications for a receiver having high sensitivity starting from single photons, superior time-offlight resolution, robustness including surviving at bright light flashes, solid-state compactness and more, are expected to be feasible for the SiPMs. Despite some known drawbacks, namely crosstalk, afterpulsing, dark noise, limited dynamic range, SiPMs are already considered as promising substitutes for conventional APDs and PMTs in LIDAR applications. However, these initial considerations are based on a rather simplified representation of the SiPM as a generic LIDAR receiver described by generic expressions. This study is focused on a comprehensive evaluation of a SiPM potential considering essential features of this new technology, which could affect applicability and performance of SiPMs as LIDAR receivers. Namely, an excess noise due to correlated processes of crosstalk and afterpulsing, are included into account utilizing the well-established framework of analytical probabilistic models. The analysis of SiPM performance in terms of a photon number and time resolution clarifies their competitiveness over conventional APD and PMT and anticipates the development of next SiPM generations.

  11. PARISROC, a Photomultiplier Array Integrated Read Out Chip

    CERN Document Server

    Di Lorenzo, S Conforti; Dulucq, F; De La Taille, C; Martin-Chassard, G; Berni, M El; Wei, W

    2010-01-01

    PARISROC is a complete read out chip, in AMS SiGe 0.35 !m technology, for photomultipliers array. It allows triggerless acquisition for next generation neutrino experiments and it belongs to an R&D program funded by the French national agency for research (ANR) called PMm2: ?Innovative electronics for photodetectors array used in High Energy Physics and Astroparticles? (ref.ANR-06-BLAN-0186). The ASIC (Application Specific Integrated Circuit) integrates 16 independent and auto triggered channels with variable gain and provides charge and time measurement by a Wilkinson ADC (Analog to Digital Converter) and a 24-bit Counter. The charge measurement should be performed from 1 up to 300 photo- electrons (p.e.) with a good linearity. The time measurement allowed to a coarse time with a 24-bit counter at 10 MHz and a fine time on a 100ns ramp to achieve a resolution of 1 ns. The ASIC sends out only the relevant data through network cables to the central data storage. This paper describes the front-end electroni...

  12. (Hybrid) Baryons Symmetries and Masses

    CERN Document Server

    Page, P R

    1999-01-01

    We construct (hybrid) baryons in the flux-tube model of Isgur and Paton. In the limit of adiabatic quark motion, we build proper eigenstates of orbital angular momentum and construct the flavour, spin and J^P of hybrid baryons from the symmetries of the system. The lowest mass hybrid baryon is estimated at approximately 2 GeV.

  13. Energy Resolution of Ce:GAGG and Pr:LuAG Scintillators Coupled to 3 {mm} × 3 {mm} Silicon Photomultipliers

    Science.gov (United States)

    Stewart, Andrew George; Seitz, Bjoern; O'Neill, Kevin; Wall, Liam; Jackson, J. Carl

    2016-10-01

    Silicon Photomultipliers (SiPM) have shown great promise as a suitable replacement for conventional vacuum based Photomultiplier Tubes (PMT). Progress in recent years has been vast with SiPM sensors pushing the boundaries in energy and timing resolution as well as photon detection efficiency and active surface area. In this study we report the energy resolution and linearity of two novel scintillator crystals, Cerium doped Gd3Al2Ga3O12 (Ce:GAGG) and Praseodymium doped Lu3Al5O12 (Pr:LuAG), readout by three different types of 3 × 3 mm2 silicon photomultiplier sensors produced by SensL (MicroFM, MicroFB, MicroFC). Such a scintillator-SiPM architecture has applications in pre-clinical and clinical medical imaging modalities such as Positron Emission Tomography (PET). N-on-P (M series), P-on-N (B series) and low-noise P-on-N (C series) versions of the SiPM sensor platform have been coupled to the crystals and the response characterized over a range of gamma energies and detector bias values. A saturation-corrected energy resolution of 11.7% was achieved for a MicroFM device coupled to a 3 × 3 × 30 mm3 Ce:GAGG crystal at 20°C. An energy resolution of 16.1% was obtained for a MicroFB device optically coupled to to a 3 × 3 × 30 mm3 Pr:LuAG crystal at 20°C.

  14. Performance evaluation of neuro-PET using silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jiwoong; Choi, Yong, E-mail: ychoi@sogang.ac.kr; Jung, Jin Ho, E-mail: jinho1115@gmail.com; Kim, Sangsu; Im, Ki Chun

    2016-05-21

    Recently, we have developed the second prototype Silicon photomultiplier (SiPM) based positron emission tomography (PET) scanner for human brain imaging. The PET system was comprised of detector block which consisted of 4×4 SiPMs and 4×4 Lutetium Yttrium Orthosilicate arrays, charge signal transmission method, high density position decoder circuit and FPGA-embedded ADC boards. The purpose of this study was to evaluate the performance of the newly developed neuro-PET system. The energy resolution, timing resolution, spatial resolution, sensitivity, stability of the photo-peak position and count rate performance were measured. Tomographic image of 3D Hoffman brain phantom was also acquired to evaluate imaging capability of the neuro-PET. The average energy and timing resolutions measured for 511 keV gamma rays were 17±0.1% and 3±0.3 ns, respectively. Spatial resolution and sensitivity at the center of field of view (FOV) were 3.1 mm and 0.8%, respectively. The average scatter fraction was 0.4 with an energy window of 350–650 keV. The maximum true count rate and maximum NECR were measured as 43.3 kcps and 6.5 kcps at an activity concentration of 16.7 kBq/ml and 5.5 kBq/ml, respectively. Long-term stability results show that there was no significant change in the photo-peak position, energy resolution and count rate for 60 days. Phantom imaging studies were performed and they demonstrated the feasibility for high quality brain imaging. The performance tests and imaging results indicate that the newly developed PET is useful for brain imaging studies, if the axial FOV is extended to improve the system sensitivity.

  15. Characterization of strontium iodide scintillators with silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Lee J.; Phlips, Bernard

    2016-06-01

    This work characterizes a commercially available europium-doped strontium iodide detector recently developed by Radiation Monitoring Devices (RMD). The detector has been chosen for a space-based mission scheduled to launch in early 2017. The primary goal of this work was to characterize the detector's response over the expected operational range of −10 °C to 30 °C as well as the expected operational voltage range of +26.5–+28.5 V and identify background interferences that may develop due to neutron activation produced by cosmic-ray interactions. The 8 mm×8 mm×20 mm detectors use KETEK silicon photomultipliers (SiPM), with an active area of 6 mmx6 mm (KETEK PM6660). Our results show substantial integral nonlinearity due to the SiPM ranging from 0% to 25% at room temperature over the energy range of 80–2614 keV. The nonlinearity, a function of temperature and overvoltage, leads to an underestimate of the full width at half max (FWHM), which is 2.6% uncorrected at 662 keV and 3.8% corrected at 662 keV. The temperature dependence of the detector results in a noise threshold that increases substantially above 30 °C due to the SiPM dark rate. In an effort to simulate the harsh environment of space, neutron activation of the detector was also explored. Gamma-ray lines at 127 keV and 164 keV were observed in the detector along with Kα x-rays associated with europium. Beta decay from europium- and iodine-activation products were also observed within the detector.

  16. A large area, silicon photomultiplier-based PET detector module.

    Science.gov (United States)

    Raylman, Rr; Stolin, A; Majewski, S; Proffitt, J

    2014-01-21

    The introduction of silicon photomultipliers (SiPM) has facilitated construction of compact, efficient and magnetic field-hardened positron emission tomography (PET) scanners. To take full advantage of these devices, methods for using them to produce large field-of-view PET scanners are needed. In this investigation, we explored techniques to combine two SiPM arrays to form the building block for a small animal PET scanner. The module consists of a 26 × 58 array of 1.5 × 1.5mm(2) LYSO elements (spanning 41 × 91mm(2)) coupled to two SensL SiPM arrays. The SiPMs were read out with new multiplexing electronics developed for this project. To facilitate calculation of event position with multiple SiPM arrays it was necessary to spread scintillation light amongst a number of elements with a small light guide. This method was successful in permitting identification of all detector elements, even at the seam between two SiPM arrays. Since the performance of SiPMs is enhanced by cooling, the detector module was fitted with a cooling jacket, which allowed the temperature of the device and electronics to be controlled. Testing demonstrated that the peak-to-valley contrast ratio of the light detected from the scintillation array was increased by ∼45% when the temperature was reduced from 28 °C to 16 °C. Energy resolution for 511 keV photons improved slightly from 18.8% at 28 °C to 17.8% at 16 °C. Finally, the coincidence timing resolution of the module was found to be insufficient for time-of-flight applications (∼2100 ps at 14 °C). The first use of these new modules will be in the construction of a small animal PET scanner to be integrated with a 3T clinical magnetic resonance imaging scanner.

  17. Performance evaluation of neuro-PET using silicon photomultipliers

    Science.gov (United States)

    Jung, Jiwoong; Choi, Yong; Jung, Jin Ho; Kim, Sangsu; Im, Ki Chun

    2016-05-01

    Recently, we have developed the second prototype Silicon photomultiplier (SiPM) based positron emission tomography (PET) scanner for human brain imaging. The PET system was comprised of detector block which consisted of 4×4 SiPMs and 4×4 Lutetium Yttrium Orthosilicate arrays, charge signal transmission method, high density position decoder circuit and FPGA-embedded ADC boards. The purpose of this study was to evaluate the performance of the newly developed neuro-PET system. The energy resolution, timing resolution, spatial resolution, sensitivity, stability of the photo-peak position and count rate performance were measured. Tomographic image of 3D Hoffman brain phantom was also acquired to evaluate imaging capability of the neuro-PET. The average energy and timing resolutions measured for 511 keV gamma rays were 17±0.1% and 3±0.3 ns, respectively. Spatial resolution and sensitivity at the center of field of view (FOV) were 3.1 mm and 0.8%, respectively. The average scatter fraction was 0.4 with an energy window of 350-650 keV. The maximum true count rate and maximum NECR were measured as 43.3 kcps and 6.5 kcps at an activity concentration of 16.7 kBq/ml and 5.5 kBq/ml, respectively. Long-term stability results show that there was no significant change in the photo-peak position, energy resolution and count rate for 60 days. Phantom imaging studies were performed and they demonstrated the feasibility for high quality brain imaging. The performance tests and imaging results indicate that the newly developed PET is useful for brain imaging studies, if the axial FOV is extended to improve the system sensitivity.

  18. Silicon photomultiplier (SPM) detection of low-level bioluminescence for the development of deployable whole-cell biosensors: Possibilities and limitations

    Science.gov (United States)

    Li, Huaqing; Lopes, Nicholas; Moser, Scott; Sayler, Gary; Ripp, Steven

    2015-01-01

    Whole-cell bacterial bioreporters await miniaturized photon counting modules with high sensitivity and robust compatible hardware to fulfill their promise of versatile, on-site biosensor functionality. In this study, we explore the photon counting readout properties of the silicon photomultiplier (SPM) with a thermoelectric cooler and the possibilities of detecting low-level bioluminescent signals. Detection performance was evaluated through a simulated LED light source and the bioluminescence produced by the genetically engineered Pseudomonas fluorescens bacterial bioreporter 5RL. Compared with the conventional photomultiplier tube (PMT), the results revealed that the cooled SPM exhibits a wider linear response to inducible substrate concentrations (salicylate) ranging from 250 to 5000 ppb. Although cooling of the SPM lowered dark count rates and improved the minimum detectable signal, and the application of a digital filter enhanced the signal-to-noise ratio, the detection of very low light signals is still limited and remains a challenge in the design of compact photon counting systems. PMID:22305444

  19. Chest tube insertion

    Science.gov (United States)

    ... tube insertion; Insertion of tube into chest; Tube thoracostomy; Pericardial drain ... Kirsch TD, Sax J. Tube thoracostomy. In: Roberts JR, ed. Roberts and ... . 6th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 10.

  20. Jejunostomy feeding tube

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000181.htm Jejunostomy feeding tube To use the sharing features on this ... vomiting Your child's stomach is bloated Alternate Names Feeding - jejunostomy tube; G-J tube; J-tube; Jejunum ...

  1. Compact Pulse Width Modulation Circuitry for Silicon Photomultiplier Readout

    Science.gov (United States)

    Bieniosek, M F; Olcott, P D; Levin, C S

    2013-01-01

    The adoption of solid state photo-detectors for positron emission tomography (PET) system design and the interest in 3D interaction information from PET detectors has lead to an increasing number of readout channels in PET systems. To handle these additional readout channels, PET readout electronics should be simplified to reduce the power consumption, cost, and size of the electronics for a single channel. Pulse width modulation (PWM), where detector pulses are converted to digital pulses with width proportional to the detected photon energy, promises to simplify PET readout by converting the signals to digital form at the beginning of the processing chain, and allowing a single time-to-digital converter to perform the data acquisition for many channels rather than routing many analog channels and digitizing in the back end. Integrator based PWM systems, also known as charge-to-time converters (QTC), are especially compact, reducing the front-end electronics to an op-amp integrator with a resistor discharge, and a comparator. QTCs, however, have a long dead-time during which dark count noise is integrated, reducing the output signal to noise ratio. This work presents a QTC based PWM circuit with a gated integrator that shows performance improvements over existing QTC based PWM. By opening and closing an analog switch on the input of the integrator, the circuit can be controlled to integrate only the portions of the signal with a high signal-to-noise ratio. It also allows for multiplexing different detectors into the same PWM circuit while avoiding uncorrelated noise propagation between photodetector channels. Four gated integrator PWM circuits were built to readout the spatial channels of two position sensitive solid state photomultiplier (PS-SSPM). Results show a 4×4 array 0.9mm×0.9mm×15mm of LYSO crystals being identified on the 5mm×5mm PS-SSPM at room temperature with no degradation for 2-fold multiplexing. In principle, much larger multiplexing ratios are

  2. Optimizing timing performance of silicon photomultiplier-based scintillation detectors.

    Science.gov (United States)

    Yeom, Jung Yeol; Vinke, Ruud; Levin, Craig S

    2013-02-21

    Precise timing resolution is crucial for applications requiring photon time-of-flight (ToF) information such as ToF positron emission tomography (PET). Silicon photomultipliers (SiPM) for PET, with their high output capacitance, are known to require custom preamplifiers to optimize timing performance. In this paper, we describe simple alternative front-end electronics based on a commercial low-noise RF preamplifier and methods that have been implemented to achieve excellent timing resolution. Two radiation detectors with L(Y)SO scintillators coupled to Hamamatsu SiPMs (MPPC S10362-33-050C) and front-end electronics based on an RF amplifier (MAR-3SM+), typically used for wireless applications that require minimal additional circuitry, have been fabricated. These detectors were used to detect annihilation photons from a Ge-68 source and the output signals were subsequently digitized by a high speed oscilloscope for offline processing. A coincident resolving time (CRT) of 147 ± 3 ps FWHM and 186 ± 3 ps FWHM with 3 × 3 × 5 mm(3) and with 3 × 3 × 20 mm(3) LYSO crystal elements were measured, respectively. With smaller 2 × 2 × 3 mm(3) LSO crystals, a CRT of 125 ± 2 ps FWHM was achieved with slight improvement to 121 ± 3 ps at a lower temperature (15° C). Finally, with the 20 mm length crystals, a degradation of timing resolution was observed for annihilation photon interactions that occur close to the photosensor compared to shallow depth-of-interaction (DOI). We conclude that commercial RF amplifiers optimized for noise, besides their ease of use, can produce excellent timing resolution comparable to best reported values acquired with custom readout electronics. On the other hand, as timing performance degrades with increasing photon DOI, a head-on detector configuration will produce better CRT than a side-irradiated setup for longer crystals.

  3. Particle trackers based on 1 mm and 0.7 mm scintillating fibers readout by a multi-anode photomultiplier

    Science.gov (United States)

    Leverington, Blake; Rosellini, Rossano; Anelli, Mario; Campana, Pierluigi

    2013-08-01

    A prototype particle tracking detector was constructed at LNF with 1 mm and 0.7 mm plastic scintillating fibers with a 64 channel Hamamatsu H7546A-200 Ultra-bialkali flat-panel multi-anode photomultiplier readout. Cosmic ray tracks from an array of 11 gas-filled drift tubes were matched to signals in the scintillating fibers in order to measure the resolution and efficiency of tracks reconstructed in the fiber-based tracker. The fibers allow for two possible readout methods, a hit-based (digital) and an amplitude-based (analog) mode. A GEANT4 detector simulation was also developed to compare cosmic ray data with Monte Carlo results. These fiber tracker designs are suggested as a way to meet the resolution and efficiency goals of modern detectors, such as an upgraded LHCb Outer Tracker. Resolutions for the fiber trackers were found to be 0.236 mm and 0.175 mm for the 1 mm and 0.7 mm trackers, respectively, in analog mode.

  4. Multi-time-over-threshold technique for photomultiplier signal processing: Description and characterization of the SCOTT ASIC

    Energy Technology Data Exchange (ETDEWEB)

    Ferry, S. [CEA/Irfu/SPP, Gif-sur-Yvette (France); Guilloux, F., E-mail: fabrice.guilloux@cea.fr [CEA/Irfu/SEDI, Gif-sur-Yvette (France); Anvar, S.; Chateau, F.; Delagnes, E.; Gautard, V.; Louis, F.; Monmarthe, E.; Le Provost, H. [CEA/Irfu/SEDI, Gif-sur-Yvette (France); Russo, S. [Dipartimento di Scienze Fisiche Universita di Napoli, Napoli (Italy); Schuller, J.-P.; Stolarczyk, Th.; Vallage, B. [CEA/Irfu/SPP, Gif-sur-Yvette (France); Zonca, E. [CEA/Irfu/SEDI, Gif-sur-Yvette (France)

    2012-12-11

    KM3NeT aims to build a cubic-kilometer scale neutrino telescope in the Mediterranean Sea based on a 3D array of photomultiplier tubes. A dedicated ASIC, named SCOTT, has been developed for the readout electronics of the PMTs: it uses up to 16 adjustable thresholds to digitize the signals with the multi-time-over-threshold technique. Digital outputs of discriminators feed a circular sampling memory and a 'first in first out' digital memory for derandomization. At the end of the data processing, the ASIC produces a digital waveform sampled at 800 MHz. A specific study was carried out to process PMT data and has showed that five specifically chosen thresholds are suited to reach the required timing precision. A dedicated method based on the duration of the signal over a given threshold allows an equivalent timing precision at any charge. A charge estimator using the information from the thresholds allows a charge determination within less than 20% up to 60 pe.

  5. Segmented scintillation detectors with silicon photomultiplier readout for measuring antiproton annihilations.

    Science.gov (United States)

    Sótér, A; Todoroki, K; Kobayashi, T; Barna, D; Horváth, D; Hori, M

    2014-02-01

    The Atomic Spectroscopy and Collisions Using Slow Antiprotons experiment at the Antiproton Decelerator (AD) facility of CERN constructed segmented scintillators to detect and track the charged pions which emerge from antiproton annihilations in a future superconducting radiofrequency Paul trap for antiprotons. A system of 541 cast and extruded scintillator bars were arranged in 11 detector modules which provided a spatial resolution of 17 mm. Green wavelength-shifting fibers were embedded in the scintillators, and read out by silicon photomultipliers which had a sensitive area of 1 × 1 mm(2). The photoelectron yields of various scintillator configurations were measured using a negative pion beam of momentum p ≈ 1 GeV/c. Various fibers and silicon photomultipliers, fiber end terminations, and couplings between the fibers and scintillators were compared. The detectors were also tested using the antiproton beam of the AD. Nonlinear effects due to the saturation of the silicon photomultiplier were seen at high annihilation rates of the antiprotons.

  6. Application of the silicon photomultipliers for detectors in the GlueX experiment

    Energy Technology Data Exchange (ETDEWEB)

    Somov, Sergey V. [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoe shosse 31, Moscow, 115409, Russia; Tolstukhin, Ivan [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoe shosse 31, Moscow, 115409, Russia; Somov, Alexander S. [Jefferson Lab, Newport News, VA

    2015-11-01

    The GlueX detector in Hall D at Jefferson Lab is instrumented with about 5000 Silicon Photomultipliers (SiPM) manufactured by Hamamatsu Corporation [2]. These photo sensors have properties similar to conventional photomultipliers but can be operated at high magnetic fields. Silicon photomultipliers with a sensitive area of 3x3 mm2 are used to detect light from the following GlueX scintillator detectors: the tagger microscope, pair spectrometer, and start counter. Arrays of 4x4 SiPMs sensors were chosen for the instrumentation of the barrel electromagnetic calorimeter. The tagger microscope must operate at high rates (up to 2.5 MHz) and provide time measurements with a resolution better than 0.3 ns. The paper will describe some results of the characterization of SiPMs for various GlueX sub-detectors.

  7. Segmented scintillation detectors with silicon photomultiplier readout for measuring antiproton annihilations

    CERN Document Server

    Sótér, A; Kobayashi, T; Barna, D; Horvath, D; Hori, M

    2014-01-01

    The Atomic Spectroscopy and Collisions Using Slow Antiprotons (ASACUSA) experiment at the Antiproton Decelerator (AD) facility of CERN constructed segmented scintillators to detect and track the charged pions which emerge from antiproton annihilations in a future superconducting radiofrequency Paul trap for antiprotons. A system of 541 cast and extruded scintillator bars were arranged in 11 detector modules which provided a spatial resolution of 17 mm. Green wavelength-shifting fibers were embedded in the scintillators, and read out by silicon photomultipliers which had a sensitive area of 1 x 1 mm^2. The photoelectron yields of various scintillator configurations were measured using a negative pion beam of momentum p ~ 1 GeV/c. Various fibers and silicon photomultipliers, fiber end terminations, and couplings between the fibers and scintillators were compared. The detectors were also tested using the antiproton beam of the AD. Nonlinear effects due to the saturation of the silicon photomultiplier were seen a...

  8. Very high-gain and low-excess noise near-infrared single-photon avalanche detector: an NIR solid state photomultiplier

    Science.gov (United States)

    Linga, Krishna; Yevtukhov, Yuriy; Liang, Bing

    2009-05-01

    A new family of photodetectors with a Discrete Amplification (DA) mechanism allows the realization of very high gain and low excess noise factor in the visible and near infrared spectral regions and offers an alternative to conventional photomultiplier tubes and Geiger mode avalanche photodetectors. These photodetectors can operate in linear detection mode with gain-bandwidth product in excess of 4X1014 and in photon counting mode with count rates up to 108 counts/sec. Potential benefits of this technology over conventional avalanche photodetectors include ultra low excess noise factor, very high gain, and lower reset time (photodetectors in the near infrared wavelength range. The measured devices have the following performance characteristics: gain > 2X105, excess noise factor Lidar, quantum cryptography, night vision and other military, defence and aerospace applications.

  9. Study of the Light Emission Process from the Double Chooz Photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Calvo, E.; Cerrada, M.; Crespo, J. I.; Gil-Botella, I.; Jimenez, S.; Lopez, M.; Novella, P.; Palomares, C.; Santorelli, R.; Verdugo, A.

    2012-09-13

    In this document we present a study of the light emitted by the base of a Hamamatsu R7081MOD-ASSY photomultiplier (PMT) of the same type used in the Double Chooz experiment. Several characteristic features of the light signal have been found in terms of amplitude, length and pulse shape. Additional investigations on the properties of the epoxy used to cover the photomultiplier base have been carried out. A possible explanation of the light emission process is discussed at the end of the study. (Author) 1 ref.

  10. A new multianodic large area photomultiplier to be used in underwater neutrino detectors

    Energy Technology Data Exchange (ETDEWEB)

    Aiello, S. [INFN Sezione Catania, Via S. Sofia 64, 95123 Catania (Italy); Amore, A. [Dipartimento di Fisica e Astronomia, Universita di Catania, Via S. Sofia 64, 95123 Catania (Italy); Anghinolfi, M.; Battaglieri, M. [INFN, sezione di Genova, Via Dodecaneso 33, I-16146 Genova (Italy); Bersani, A. [Dipartimento di Fisica dell' Universita di Genova, Via Dodecaneso 33, 16146 Genova (Italy); INFN, sezione di Genova, Via Dodecaneso 33, I-16146 Genova (Italy); Brunoldi, M. [Dipartimento di Fisica dell' Universita di Genova, Via Dodecaneso 33, 16146 Genova (Italy); Caponetto, L. [INFN Sezione Catania, Via S. Sofia 64, 95123 Catania (Italy); De Vita, R.; Fratini, K. [INFN, sezione di Genova, Via Dodecaneso 33, I-16146 Genova (Italy); Grimaldi, A. [INFN Sezione Catania, Via S. Sofia 64, 95123 Catania (Italy); Kulikovskiy, V. [Institute of Nuclear Physics, Moscow State University, 119899 Moscow (Russian Federation); Leonora, E. [INFN Sezione Catania, Via S. Sofia 64, 95123 Catania (Italy); Lo Presti, D. [Dipartimento di Fisica e Astronomia, Universita di Catania, Via S. Sofia 64, 95123 Catania (Italy); INFN Sezione Catania, Via S. Sofia 64, 95123 Catania (Italy); Mini, G. [Dipartimento di Fisica dell' Universita di Genova, Via Dodecaneso 33, 16146 Genova (Italy); Minutoli, S.; Musico, P.; Osipenko, M.; Ottonello, G.; Piombo, D. [INFN, sezione di Genova, Via Dodecaneso 33, I-16146 Genova (Italy); Randazzo, N. [INFN Sezione Catania, Via S. Sofia 64, 95123 Catania (Italy)] (and others)

    2009-07-01

    In this article we describe the properties of a new 10-in. hemispherical photomultiplier manufactured by Hamamatsu. The prototype has a segmented photocathode and four independent amplification stages. The photomultiplier is one of the main components of a newly designed direction-sensitive optical module to be employed in large-scale underwater neutrino telescopes. The R and D activity has been co-funded by the INFN and the KM3NeT Consortium. The prototype performance fully meets with the design specifications.

  11. A tube-in-tube thermophotovoltaic generator

    Energy Technology Data Exchange (ETDEWEB)

    Ashcroft, J.; Campbell, B.; Depoy, D.

    1996-12-31

    A thermophotovoltaic device includes at least one thermal radiator tube, a cooling tube concentrically disposed within each thermal radiator tube and an array of thermophotovoltaic cells disposed on the exterior surface of the cooling tube. A shell having a first end and a second end surrounds the thermal radiator tube. Inner and outer tubesheets, each having an aperture corresponding to each cooling tube, are located at each end of the shell. The thermal radiator tube extends within the shell between the inner tubesheets. The cooling tube extends within the shell through the corresponding apertures of the two inner tubesheets to the corresponding apertures of the two outer tubesheets. A plurality of the thermal radiator tubes can be arranged in a staggered or an in-line configuration within the shell.

  12. Test of scintillating bars coupled to Silicon Photomultipliers for a charged particle tracking device

    CERN Document Server

    Cecchini, S; Esposti, L Degli; Lax, I; Mandrioli, G; Mauri, N; Pasqualini, L; Patrizii, L; Pozzato, M; Sirri, G; Tenti, M

    2016-01-01

    The results obtained in laboratory tests, using scintillator bars read by silicon photomultipliers are reported. The present approach is the first step for designing a precision tracking system to be placed inside a free magnetized volume for the charge identification of low energy crossing particles. The devised system is demonstrated able to provide a spatial resolution better than 2 mm.

  13. Development of a thermal neutron detector based on scintillating fibers and silicon photomultipliers.

    Science.gov (United States)

    Barbagallo, Massimo; Cosentino, Luigi; Greco, Giuseppe; Montereali, Rosa Maria; Pappalardo, Alfio; Scirè, Carlotta; Scirè, Sergio; Vincenti, Maria Aurora; Finocchiaro, Paolo

    2010-09-01

    We propose a technique for thermal neutron detection, based on a (6)Li converter placed in front of scintillating fibers readout by means of silicon photomultipliers. Such a technique allows building cheap and compact detectors and dosimeters, thus possibly opening new perspectives in terms of granular monitoring of neutron fluxes as well as space-resolved neutron detection.

  14. A method to stabilise the performance of negatively fed KM3NeT photomultipliers

    NARCIS (Netherlands)

    Adrián-Martínez, S.; Ageron, M.; Aiello, S.; Albert, A.; Ameli, F.; Anassontzis, E.G.; Andre, M.; Androulakis, G.; Anghinolfi, M.; Anton, G.; Ardid, M.; Avgitas, T.; Barbarino, G.; Barbarito, E.; Baret, B.; Barrios-Martí, J.; Belias, A.; Berbee, E.; Berg, A. van den; Bertin, V.; Beurthey, S.; Beveren, V. van; Beverini, N.; Biagi, S.; Biagioni, A.; Billault, M.; Bondì, M.; Bormuth, R.; Bouhadef, B.; Bourlis, G.; Bourret, S.; Boutonnet, C.; Bouwhuis, M.; Bozza, C.; Bruijn, R.; Brunner, J.; Buis, E.J.; Buompane, R.; Busto, J.; Cacopardo, G.; Caillat, L.; Calamai, M.; Calvo, D.; Capone, A.; Caramete, L.; Cecchini, S.; Celli, S.; Champion, C.; Cherubini, S.; Chiarella, V.; Chiarelli, L.; Chiarusi, T.; Circella, M.; Classen, L.; Cobas, D.; Cocimano, R.; Coelho, J.A.B.; Coleiro, A.; Colonges, S.; Coniglione, R.; Cordelli, M.; Cosquer, A.; Coyle, P.; Creusot, A.; Cuttone, G.; D'Amato, C.; D'Amico, A.; D'Onofrio, A.; De Bonis, G.; De Sio, C.; Di Capua, F.; Di Palma, I.; Distefano, C.; Donzaud, C.; Dornic, D.; Dorosti-Hasankiadeh, Q.; Drakopoulou, E.; Drouhin, D.; Durocher, M.; Eberl, T.; Eichie, S.; Van Eijk, D.; El Bojaddaini, I.; Elsaesser, D.; Enzenhöfer, A.; Favaro, M.; Fermani, P.; Ferrara, G.; Frascadore, G.; Furini, M.; Fusco, L.A.; Gal, T.; Galatà, S.; Garufi, F.; Gay, P.; Gebyehu, M.; Giacomini, F.; Gialanella, L.; Giordano, V.; Gizani, N.; Gracia, R.; Graf, K.; Grégoire, T.; Grella, G.; Grmek, A.; Guerzoni, M.; Habel, R.; Hallmann, S.; Haren, H. van; Harissopulos, S.; Heid, T.; Heijboer, A.; Heine, E.; Henry, S.; Hernández-Rey, J.J.; Hevinga, M.; Hofestädt, J.; Hugon, C.M.F.; Illuminati, G.; James, C.W.; Jansweijer, P.; Jongen, M.; Jong, M. de; Kadler, M.; Kalekin, O.; Kappes, A.; Katz, U.F.; Keller, P.; Kieft, G.; Kießling, D.; Koffeman, E.N.; Kooijman, P.; Kouchner, A.; Kreter, M.; Kulikovskiy, V.; Lahmann, R.; Lamare, P.; Leisos, A.; Leonora, E.; Clark, M.L.; Liolios, A.; Alvarez, C.D.L.; Lo Presti, D.; Löhner, H.; Lonardo, A.; Lotze, M.; Loucatos, S.; Maccioni, E.; Mannheim, K.; Manzali, M.; Margiotta, A.; Margotti, A.; Marinelli, A.; Mariš, O.; Markou, C.; Martínez-Mora, J.A.; Martini, A.; Marzaioli, F.; Mele, R.; Melis, K.W.; Michael, T.; Migliozzi, P.; Migneco, E.; Mijakowski, P.; Miraglia, A.; Mollo, C.M.; Mongelli, M.; Morganti, M.; Moussa, A.; Musico, P.; Musumeci, M.; Nicolau, C.A.; Olcina, I.; Olivetto, C.; Orlando, A.; Orzelli, A.; Pancaldi, G.; Paolucci, A.; Papaikonomou, A.; Papaleo, R.; Pǎvǎlaš, G.E.; Peek, H.; Pellegrini, G.; Pellegrino, C.; Perrina, C.; Pfutzner, M.; Piattelli, P.; Pikounis, K.; Poma, G.E.; Popa, V.; Pradier, T.; Pratolongo, F.; Pühlhofer, G.; Pulvirenti, S.; Quinn, L.; Racca, C.; Raffaelli, F.; Randazzo, N.; Real, D.; Resvanis, L.; Reubelt, J.; Riccobene, G.; Rossi, C.; Rovelli, A.; Saldaña, M.; Salvadori, I.; Samtleben, D.F.E.; Sánchez García, A.; Sánchez Losa, A.; Sanguineti, M.; Santangelo, A.; Santonocito, D.; Sapienza, P.; Schimmel, F.; Schmelling, J.; Schnabel, J.; Sciacca, V.; Sedita, M.; Seitz, T.; Sgura, I.; Simeone, F.; Sipala, V.; Spisso, B.; Spurio, M.; Stavropoulos, G.; Steijger, J.; Stellacci, S.M.; Stransky, D.; Taiuti, M.; Tayalati, Y.; Terrasi, F.; Tézier, D.; Theraube, S.; Timmer, P.; Tönnis, C.; Trasatti, L.; Travaglini, R.; Trovato, A.; Tsirigotis, A.; Tzamarias, S.; Tzamariudaki, E.; Vallage, B.; Van Elewyck, V.; Vermeulen, J.; Versari, F.; Vicini, P.; Viola, S.; Vivolo, D.; Volkert, M.; Wiggers, L.; Wilms, J.; Wolf, E. de; Zachariadou, K.; Zani, S.; Zornoza, J.D.; Zúñiga, J.

    2016-01-01

    The KM3NeT research infrastructure, currently under construction in the Mediterranean Sea, will host neutrino telescopes for the identification of neutrino sources in the Universe and for studies of the neutrino mass hierarchy. These telescopes will house hundreds of thousands of photomultiplier

  15. EQUIPMENTS TO SINGLE PHOTON REGISTRATION. Part 2. SILICON PHOTOMULTIPLIER SIGNAL PRELIMINARY PROCESSING. (Review

    Directory of Open Access Journals (Sweden)

    O. V. Dvornikov

    2013-01-01

    Full Text Available Bias circuits, output signals and readout electronics of silicon photomultipliers are considered. Requirements to analog IC for SiPM signal preliminary processing are formulated. According to requirements the set of radiation hardened analog ICs including the comparator and transresistance amplifiers with different gain and speed is produced.

  16. Characterization of large-area photomultipliers under low magnetic fields: Design and performance of the magnetic shielding for the Double Chooz neutrino experiment

    Energy Technology Data Exchange (ETDEWEB)

    Calvo, E.; Cerrada, M.; Fernandez-Bedoya, C.; Gil-Botella, I. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Av. Complutense 22, 28040 Madrid (Spain); Palomares, C., E-mail: mc.palomares@ciemat.e [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Av. Complutense 22, 28040 Madrid (Spain); Rodriguez, I.; Toral, F.; Verdugo, A. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Av. Complutense 22, 28040 Madrid (Spain)

    2010-09-21

    A precise quantitative measurement of the effect of low magnetic fields in Hamamatsu R7081 photomultipliers has been performed. These large-area photomultipliers will be used in the Double Chooz neutrino experiment. A magnetic shielding has been developed for these photomultipliers. Its design and performance is also reported in this paper.

  17. Feeding tube - infants

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007235.htm Feeding tube - infants To use the sharing features on this page, please enable JavaScript. A feeding tube is a small, soft, plastic tube placed ...

  18. Tube-shape verifier

    Science.gov (United States)

    Anderson, A. N.; Christ, C. R.

    1980-01-01

    Inexpensive apparatus checks accuracy of bent tubes. Assortment of slotted angles and clamps is bolted down to flat aluminum plate outlining shape of standard tube bent to desired configuration. Newly bent tubes are then checked against this outline. Because parts are bolted down, tubes can be checked very rapidly without disturbing outline. One verifier per tube-bending machine can really speed up production in tube-bending shop.

  19. Development of a PET/Cerenkov-light hybrid imaging system

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Seiichi, E-mail: s-yama@met.nagoya-u.ac.jp; Hamamura, Fuka; Kato, Katsuhiko; Ogata, Yoshimune [Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine, Aichi 461-8673 (Japan); Watabe, Tadashi; Ikeda, Hayato; Kanai, Yasukazu; Hatazawa, Jun [Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine, Osaka 565-0871 (Japan); Watabe, Hiroshi [CYRIC, Tohoku University, Miyagi 980-8578 (Japan)

    2014-09-15

    Purpose: Cerenkov-light imaging is a new molecular imaging technology that detects visible photons from high-speed electrons using a high sensitivity optical camera. However, the merit of Cerenkov-light imaging remains unclear. If a PET/Cerenkov-light hybrid imaging system were developed, the merit of Cerenkov-light imaging would be clarified by directly comparing these two imaging modalities. Methods: The authors developed and tested a PET/Cerenkov-light hybrid imaging system that consists of a dual-head PET system, a reflection mirror located above the subject, and a high sensitivity charge coupled device (CCD) camera. The authors installed these systems inside a black box for imaging the Cerenkov-light. The dual-head PET system employed a 1.2 × 1.2 × 10 mm{sup 3} GSO arranged in a 33 × 33 matrix that was optically coupled to a position sensitive photomultiplier tube to form a GSO block detector. The authors arranged two GSO block detectors 10 cm apart and positioned the subject between them. The Cerenkov-light above the subject is reflected by the mirror and changes its direction to the side of the PET system and is imaged by the high sensitivity CCD camera. Results: The dual-head PET system had a spatial resolution of ∼1.2 mm FWHM and sensitivity of ∼0.31% at the center of the FOV. The Cerenkov-light imaging system's spatial resolution was ∼275μm for a {sup 22}Na point source. Using the combined PET/Cerenkov-light hybrid imaging system, the authors successfully obtained fused images from simultaneously acquired images. The image distributions are sometimes different due to the light transmission and absorption in the body of the subject in the Cerenkov-light images. In simultaneous imaging of rat, the authors found that {sup 18}F-FDG accumulation was observed mainly in the Harderian gland on the PET image, while the distribution of Cerenkov-light was observed in the eyes. Conclusions: The authors conclude that their developed PET

  20. Pollen tube behavior in different Mandarin hybrids

    OpenAIRE

    Distefano, Gaetano; Las Casas, Giuseppina; La Malfa, Stefano; Gentile, Alessandra; Tribulato, Eugenio; Herrero Romero, María

    2009-01-01

    Seedlessness is an important trait in the evaluation of commercial mandarin for fresh consumption. However, in the last decade, the presence of seeds in fruit of cultivars considered as seedless has become a problem in different citrus-growing areas because the commercial value is depreciated. Seeds have appeared concomitantly with the introduction of new cultivars that appear to be cross-compatible. To overcome this problem, different strategies have been explored, but a definitive answer is...

  1. Time-resolved single-photon detection module based on silicon photomultiplier: A novel building block for time-correlated measurement systems

    Science.gov (United States)

    Martinenghi, E.; Di Sieno, L.; Contini, D.; Sanzaro, M.; Pifferi, A.; Dalla Mora, A.

    2016-07-01

    We present the design and preliminary characterization of the first detection module based on Silicon Photomultiplier (SiPM) tailored for single-photon timing applications. The aim of this work is to demonstrate, thanks to the design of a suitable module, the possibility to easily exploit SiPM in many applications as an interesting detector featuring large active area, similarly to photomultipliers tubes, but keeping the advantages of solid state detectors (high quantum efficiency, low cost, compactness, robustness, low bias voltage, and insensitiveness to magnetic field). The module integrates a cooled SiPM with a total photosensitive area of 1 mm2 together with the suitable avalanche signal read-out circuit, the signal conditioning, the biasing electronics, and a Peltier cooler driver for thermal stabilization. It is able to extract the single-photon timing information with resolution better than 100 ps full-width at half maximum. We verified the effective stabilization in response to external thermal perturbations, thus proving the complete insensitivity of the module to environment temperature variations, which represents a fundamental parameter to profitably use the instrument for real-field applications. We also characterized the single-photon timing resolution, the background noise due to both primary dark count generation and afterpulsing, the single-photon detection efficiency, and the instrument response function shape. The proposed module can become a reliable and cost-effective building block for time-correlated single-photon counting instruments in applications requiring high collection capability of isotropic light and detection efficiency (e.g., fluorescence decay measurements or time-domain diffuse optics systems).

  2. WE-AB-BRB-03: Investigation of a Small Photomultiplier-Based Probe for Use in Beam Diagnostics and Medical Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, F; Tosh, R [NIST, Gaithersburg, MD (United States)

    2015-06-15

    Purpose: Investigate the use of a small photomultiplier-based probe as a possible beam diagnostic and medical dosimetry tool. Methods: Cerenkov emission produced by clinical accelerator beams was detected by a small photomultiplier tube (PMT). Measurements of Clinac beams were made both in air and by inserting the PMT directly into a water phantom. A conical collimator placed in front of the PMT reduced the angular acceptance and the detection of scattered light. With this arrangement, we obtained response curves as a function of depth along the central axis similar in shape and magnitude to those obtained with ionization chambers. Subsequent measurements were made with the PMT covered in aluminum foil, obtaining a signal arising primarily from direct Cerenkov light produced in the glass entrance window. With an oscilloscope and amplifier/MCA system, we were able to monitor the response to individual beam pulses and observe variations in the beam pulse shape and magnitude as a function of dose rate. Results: Using Cerenkov signals detected by a PMT, we were able to obtain reasonable beam quality metrics, and the response was found to be linear over a range of dose rates. The fast response of the PMT allowed for the observation of small changes in the shape and magnitude of the beam pulse. With this system we were able to detect small changes in the dose per pulse delivered by the accelerator. Conclusion: A small PMT probe has shown promise as a beam diagnostic and medical dosimetry tool. Its fast response allows for real time beam pulse monitoring, and the integrated response can yield relative and perhaps even absolute dose information with a properly calibrated system. For accelerator diagnostics, monitoring of the beam pulse shape can aid in beam tuning, particularly in electron mode, where no target current pulse is available.

  3. Time-resolved single-photon detection module based on silicon photomultiplier: A novel building block for time-correlated measurement systems.

    Science.gov (United States)

    Martinenghi, E; Di Sieno, L; Contini, D; Sanzaro, M; Pifferi, A; Dalla Mora, A

    2016-07-01

    We present the design and preliminary characterization of the first detection module based on Silicon Photomultiplier (SiPM) tailored for single-photon timing applications. The aim of this work is to demonstrate, thanks to the design of a suitable module, the possibility to easily exploit SiPM in many applications as an interesting detector featuring large active area, similarly to photomultipliers tubes, but keeping the advantages of solid state detectors (high quantum efficiency, low cost, compactness, robustness, low bias voltage, and insensitiveness to magnetic field). The module integrates a cooled SiPM with a total photosensitive area of 1 mm(2) together with the suitable avalanche signal read-out circuit, the signal conditioning, the biasing electronics, and a Peltier cooler driver for thermal stabilization. It is able to extract the single-photon timing information with resolution better than 100 ps full-width at half maximum. We verified the effective stabilization in response to external thermal perturbations, thus proving the complete insensitivity of the module to environment temperature variations, which represents a fundamental parameter to profitably use the instrument for real-field applications. We also characterized the single-photon timing resolution, the background noise due to both primary dark count generation and afterpulsing, the single-photon detection efficiency, and the instrument response function shape. The proposed module can become a reliable and cost-effective building block for time-correlated single-photon counting instruments in applications requiring high collection capability of isotropic light and detection efficiency (e.g., fluorescence decay measurements or time-domain diffuse optics systems).

  4. Time-resolved single-photon detection module based on silicon photomultiplier: A novel building block for time-correlated measurement systems

    Energy Technology Data Exchange (ETDEWEB)

    Martinenghi, E., E-mail: edoardo.martinenghi@polimi.it; Di Sieno, L.; Contini, D.; Dalla Mora, A. [Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Sanzaro, M. [Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Pifferi, A. [Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Istituto di Fotonica e Nanotecnologie, Consiglio Nazionale delle Ricerche, Piazza Leonardo da Vinci 32, 20133 Milano (Italy)

    2016-07-15

    We present the design and preliminary characterization of the first detection module based on Silicon Photomultiplier (SiPM) tailored for single-photon timing applications. The aim of this work is to demonstrate, thanks to the design of a suitable module, the possibility to easily exploit SiPM in many applications as an interesting detector featuring large active area, similarly to photomultipliers tubes, but keeping the advantages of solid state detectors (high quantum efficiency, low cost, compactness, robustness, low bias voltage, and insensitiveness to magnetic field). The module integrates a cooled SiPM with a total photosensitive area of 1 mm{sup 2} together with the suitable avalanche signal read-out circuit, the signal conditioning, the biasing electronics, and a Peltier cooler driver for thermal stabilization. It is able to extract the single-photon timing information with resolution better than 100 ps full-width at half maximum. We verified the effective stabilization in response to external thermal perturbations, thus proving the complete insensitivity of the module to environment temperature variations, which represents a fundamental parameter to profitably use the instrument for real-field applications. We also characterized the single-photon timing resolution, the background noise due to both primary dark count generation and afterpulsing, the single-photon detection efficiency, and the instrument response function shape. The proposed module can become a reliable and cost-effective building block for time-correlated single-photon counting instruments in applications requiring high collection capability of isotropic light and detection efficiency (e.g., fluorescence decay measurements or time-domain diffuse optics systems).

  5. The calibration system for the photomultiplier array of the SNO+ experiment

    CERN Document Server

    Alves, R; Bradbury, S; Carvalho, J; Chauhan, D; Clark, K; Coulter, I; Descamps, F; Falk, E; Gurriana, L; Kraus, C; Lefeuvre, G; Maio, A; Maneira, J; Mottram, M; Peeters, S; Rose, J; Seabra, L; Sinclair, J; Skensved, P; Waterfield, J; White, R; Wilson, J R

    2014-01-01

    A light injection system using LEDs and optical fibres was designed for the calibration and monitoring of the photomultiplier array of the SNO+ experiment at SNOLAB. Large volume, non-segmented, low-background detectors for rare event physics, such as the multi-purpose SNO+ experiment, need a calibration system that allow an accurate and regular measurement of the performance parameters of their photomultiplier arrays, while minimising the risk of radioactivity ingress. The design implemented for SNO+ uses a set of optical fibres to inject light pulses from external LEDs into the detector. The design, fabrication and installation of this light injection system, as well as the first commissioning tests, are described in this paper. Monte Carlo simulations were compared with the commissioning test results, confirming that the system meets the performance requirements.

  6. Operation and first results of the NEXT-DEMO prototype using a silicon photomultiplier tracking array

    CERN Document Server

    Álvarez, V; Cárcel, S; Castel, J; Cebrián, S; Cervera, A; Conde, C A N; Dafni, T; Dias, T H V T; Díaz, J; Egorov, M; Esteve, R; Evtoukhovitch, P; Fernandes, L M P; Ferrario, P; Ferreira, A L; Freitas, E D C; Gehman, V M; Gil, A; Goldschmidt, A; Gómez, H; Gómez-Cadenas, J J; González-Díaz, D; Gutiérrez, R M; Hauptman, J; Morata, J A Hernando; Herrera, D C; Iguaz, F J; Irastorza, I G; Jinete, M A; Labarga, L; Laing, A; Liubarsky, I; Lopes, J A M; Lorca, D; Losada, M; Luzón, G; Marí, A; Martín-Albo, J; Martínez, A; Martínez, G; Miller, T; Moiseenko, A; Monrabal, F; Monteiro, C M B; Mora, F J; Moutinho, L M; Vidal, J Muñoz; da Luz, H Natal; Navarro, G; Nebot-Guinot, M; Nygren, D; Oliveira, C A B; Palma, R; Pérez, J; Aparicio, J L Pérez; Renner, J; Ripoll, L; Rodríguez, A; Rodríguez, J; Santos, F P; Santos, J M F dos; Seguí, L; Serra, L; Shuman, D; Simón, A; Sofka, C; Sorel, M; Toledo, J F; Tomás, A; Torrent, J; Tsamalaidze, Z; Veloso, J F C A; Villar, J A; Webb, R; White, J T; Yahlali, N

    2013-01-01

    NEXT-DEMO is a high-pressure xenon gas TPC which acts as a technological test-bed and demonstrator for the NEXT-100 neutrinoless double beta decay experiment. In its current configuration the apparatus fully implements the NEXT-100 design concept. This is an asymmetric TPC, with an energy plane made of photomultipliers and a tracking plane made of silicon photomultipliers (SiPM) coated with TPB. The detector in this new configuration has been used to reconstruct the characteristic signature of electrons in dense gas. Demonstrating the ability to identify the MIP and ``blob'' regions. Moreover, the SiPM tracking plane allows for the definition of a large fiducial region in which an excellent energy resolution of 1.82% FWHM at 511 keV has been measured (a value which extrapolates to 0.83% at the xenon Qbetabeta).

  7. Characterization of Silicon Photomultiplier Readout Designs for Use in Positron Emission Tomography Systems

    Science.gov (United States)

    Liu, Chen-Yi

    Geiger-mode avalanche photodiodes, or silicon photomultipliers, are promising light sensors for the next generation Positron Emission Tomography (PET) scanners. The sensor is being used in the scanner's gamma ray detector to measure scintillation light. This thesis describes the test results of three gamma ray detectors that utilize silicon photomultipliers. The first one is a commercial detector, and the other two are custom made. The detectors are tested for their 511 keV photon energy and timing resolution, as well as their ability to measure light from small scintillator crystals. The two custom made detectors had smaller active area, but outperformed the commercial detector in energy resolution. The introduction of buffer amplifiers improved the timing resolution of one detector. All three detectors had their crystal decoding ability limited by signal multiplexing and the sensor's dark noise. Finally, a detector design was proposed for the PET system being developed in our group.

  8. Gaseous photomultipliers with solid photocathodes for the detection of sparks, flames and dangerous gases

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, P.; Francke, T.; Lund-Jensen, B.; Peskov, V. E-mail: vladimir.peskov@cern.ch

    2003-06-01

    In many applications, it is necessary to detect sparks or flames in daylight conditions or in illuminated areas. Most flames emit strongly in the ultraviolet spectrum (180-280 nm), and this property can be used for reliable identification of flames. We have developed new spark and flame detectors based on gaseous photomultipliers with CsI, CuI or CsTe photocathodes. A modified version of the detector can also detect smoke and dangerous vapors. These detectors are able to perform complex monitoring and detection functions. Some of their advantages are: low cost, high sensitivity, large output signal and operation under battery power. Gaseous photomultipliers can be position sensitive and, if necessary, be used in combination with various optical systems, for example for monitoring flames from space.

  9. Optimization of the uniformity of light yield from scintillator tiles read out directly by silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Bobchenko, B.; Chadeeva, M. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Moscow Engineering Physics Institute, Moscow (Russian Federation); Danilov, M. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Moscow Engineering Physics Institute, Moscow (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny (Russian Federation); Mironov, D., E-mail: dima.mironov@itep.ru [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Moscow Engineering Physics Institute, Moscow (Russian Federation); Moscow Institute of Physics and Technology, Dolgoprudny (Russian Federation); Rusinov, V.; Tarkovskiy, E. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Moscow Engineering Physics Institute, Moscow (Russian Federation)

    2015-07-01

    The scintillator tiles with direct readout by silicon photomultipliers (SiPM) have been studied. The SiPM is placed inside the dimple machined in the center of the big face of 30×30×3 mm{sup 3} tile. The different dimple geometries were studied. The tiles with the optimal dimple design show the uniformity of response comparable to the tiles with fiber readout. The direct-readout approach provides a reasonable way for the construction of supermultichannel calorimeters.

  10. Improvement of sensitivity in continuous wave near infra-red spectroscopy systems by using silicon photomultipliers.

    Science.gov (United States)

    Pagano, Roberto; Libertino, Sebania; Sanfilippo, Delfo; Fallica, Giorgio; Lombardo, Salvatore

    2016-04-01

    We experimentally analyze the signal-to-noise ratio of continuous wave (CW) near infrared spectroscopy (NIRS) reflectance systems based on light emitting diodes and silicon photomultipliers for high performance low cost NIRS biomedical systems. We show that under suitable experimental conditions such systems exhibit a high SNR, which allows an SDS of 7 cm, to our knowledge the largest ever demonstrated in a CW-NIRs system.

  11. Development of a scintillation detector with a photosensor based on matrices of silicon photomultipliers

    Science.gov (United States)

    Yanin, A. F.; Dzaparova, I. M.; Gorbacheva, E. A.; Kurenya, A. N.; Kochkarov, M. M.; Petkov, V. B.; Sergeev, A. V.

    2017-01-01

    Scintillation detector with matrices of silicon photomultipliers (SiPM) as multi-channel photosensors is under development. The use of SiPM matrices gives a possibility to do a snapshot of glowing track of charged particle traversing a scintillator. The snapshots of the events inside the scintillator were taken for the two SiPM matrices arrangements. The comparison characteristics of snapshots for these arrangements are presented.

  12. Scintillation neutron detectors based on solid-state photomultipliers and lightguides

    Energy Technology Data Exchange (ETDEWEB)

    Litvin, V. S., E-mail: vlitvin@inr.ru; Marin, V. N.; Karaevsky, S. K.; Trunov, D. N.; Axenov, S. N.; Stolyarov, A. A.; Sadykov, R. A. [Russian Academy of Sciences, Institute for Nuclear Research (Russian Federation)

    2016-01-15

    Neutron detectors based on scintillation screens ZnS(Ag)/LiF and solid-state photomultipliers have been developed. Lightguides are used to collect light. The application of a coincidence scheme provides a low dark count and a neutron detection efficiency as high as 70%. A scheme of x-y neutron detector based on wavelength shifting fibers is also proposed. Tests of the proposed versions of detectors in a neutron beam have shown their efficiency.

  13. Silicon photomultiplier-based Compton Telescope for Safety and Security (SCoTSS)

    CERN Document Server

    Sinclair, Laurel E; Hanna, David S; Seywerd, Henry C J; MacLeod, Audrey M L; Boyle, Patrick J

    2016-01-01

    A Compton gamma imager has been developed for use in consequence management operations and in security investigations. The imager uses solid inorganic scintillator, known for robust performance in field survey conditions. The design was constrained in overall size by the requirement that it be person transportable and operable from a variety of platforms. In order to introduce minimal dead material in the path of the incoming and scattered gamma rays, custom silicon photomultipliers (SiPMs), with a thin glass substrate, were used to collect the scintillation light from the scatter layers. To move them out of the path of the gamma rays, preamplification electronics for the silicon photomultipliers were located a distance from the imager. This imager, the Silicon photomultiplier Compton Telescope for Safety and Security (SCoTSS) is able to provide a one-degree image resolution in a plus-minus 45 degree field of view for a 10 mCi point source 40 m distant, within about one minute, for gamma-ray energies ranging ...

  14. Final definition of sets of photomultipliers for the tile hadron calorimeter of the ATLAS detector.

    CERN Document Server

    Lefèvre, R; Vazeille, F

    2001-01-01

    In order to fulfil to technical and physical requirements, the photomultiplier blocks of the tile hadron calorimeter of ATLAS have to be classified in sets corresponding to different types of cells. This note presents the final setting. It is an update of what has been done in [1]. The main difference is that it takes into account the fact that some cells of the calorimeter are equipped with tiles made of PSM polystyrene and some with tiles made of BASF polystyrene. The output light for BASF tiles is about 25% higher than for PSM ones [2]. To correct a part of this effect of non-uniformity of the calorimeter, it is foreseen here to associate photomultipliers with lower quantum efficiencies to cells equipped with BASF tiles. It leads to define six sets of photomultipliers: two for barrel like super-drawer and four for extended barrel ones. The method used to define the sets is reported and two applications are presented. The first ones takes into account the overall calorimeter needs and is based on 2445 photo...

  15. MR-compatibility assessment of the first preclinical PET-MRI insert equipped with digital silicon photomultipliers.

    Science.gov (United States)

    Wehner, J; Weissler, B; Dueppenbecker, P M; Gebhardt, P; Goldschmidt, B; Schug, D; Kiessling, F; Schulz, V

    2015-03-21

    PET (positron emission tomography) with its high sensitivity in combination with MRI (magnetic resonance imaging) providing anatomic information with good soft-tissue contrast is considered to be a promising hybrid imaging modality. However, the integration of a PET detector into an MRI system is a challenging task since the MRI system is a sensitive device for external disturbances and provides a harsh environment for electronic devices. Consequently, the PET detector has to be transparent for the MRI system and insensitive to electromagnetic disturbances. Due to the variety of MRI protocols imposing a wide range of requirements regarding the MR-compatibility, an extensive study is mandatory to reliably assess worst-case interference phenomena between the PET detector and the MRI scanner. We have built the first preclinical PET insert, designed for a clinical 3 T MRI, using digital silicon photomultipliers (digital SiPM, type DPC 3200-22, Philips Digital Photon Counting). Since no thorough interference investigation with this new digital sensor has been reported so far, we present in this work such a comprehensive MR-compatibility study. Acceptable distortion of the B0 field homogeneity (volume RMS = 0.08 ppm, peak-to-peak value = 0.71 ppm) has been found for the PET detector installed. The signal-to-noise ratio degradation stays between 2-15% for activities up to 21 MBq. Ghosting artifacts were only found for demanding EPI (echo planar imaging) sequences with read-out gradients in Z direction caused by additional eddy currents originated from the PET detector. On the PET side, interference mainly between the gradient system and the PET detector occurred: extreme gradient tests were executed using synthetic sequences with triangular pulse shape and maximum slew rate. Under this condition, a relative degradation of the energy (⩽10%) and timing (⩽15%) resolution was noticed. However, barely measurable performance deterioration occurred when morphological MRI

  16. MR-compatibility assessment of the first preclinical PET-MRI insert equipped with digital silicon photomultipliers

    Science.gov (United States)

    Wehner, J.; Weissler, B.; Dueppenbecker, P. M.; Gebhardt, P.; Goldschmidt, B.; Schug, D.; Kiessling, F.; Schulz, V.

    2015-03-01

    PET (positron emission tomography) with its high sensitivity in combination with MRI (magnetic resonance imaging) providing anatomic information with good soft-tissue contrast is considered to be a promising hybrid imaging modality. However, the integration of a PET detector into an MRI system is a challenging task since the MRI system is a sensitive device for external disturbances and provides a harsh environment for electronic devices. Consequently, the PET detector has to be transparent for the MRI system and insensitive to electromagnetic disturbances. Due to the variety of MRI protocols imposing a wide range of requirements regarding the MR-compatibility, an extensive study is mandatory to reliably assess worst-case interference phenomena between the PET detector and the MRI scanner. We have built the first preclinical PET insert, designed for a clinical 3 T MRI, using digital silicon photomultipliers (digital SiPM, type DPC 3200-22, Philips Digital Photon Counting). Since no thorough interference investigation with this new digital sensor has been reported so far, we present in this work such a comprehensive MR-compatibility study. Acceptable distortion of the B0 field homogeneity (volume RMS = 0.08 ppm, peak-to-peak value = 0.71 ppm) has been found for the PET detector installed. The signal-to-noise ratio degradation stays between 2-15% for activities up to 21 MBq. Ghosting artifacts were only found for demanding EPI (echo planar imaging) sequences with read-out gradients in Z direction caused by additional eddy currents originated from the PET detector. On the PET side, interference mainly between the gradient system and the PET detector occurred: extreme gradient tests were executed using synthetic sequences with triangular pulse shape and maximum slew rate. Under this condition, a relative degradation of the energy (⩽10%) and timing (⩽15%) resolution was noticed. However, barely measurable performance deterioration occurred when morphological MRI

  17. Feeding tube insertion - gastrostomy

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002937.htm Feeding tube insertion - gastrostomy To use the sharing features on this page, please enable JavaScript. A gastrostomy feeding tube insertion is the placement of a feeding ...

  18. Neural Tube Defects

    Science.gov (United States)

    Neural tube defects are birth defects of the brain, spine, or spinal cord. They happen in the ... that she is pregnant. The two most common neural tube defects are spina bifida and anencephaly. In ...

  19. Reaching 200-ps timing resolution in a time-of-flight and depth-of-interaction positron emission tomography detector using phosphor-coated crystals and high-density silicon photomultipliers.

    Science.gov (United States)

    Kwon, Sun Il; Ferri, Alessandro; Gola, Alberto; Berg, Eric; Piemonte, Claudio; Cherry, Simon R; Roncali, Emilie

    2016-10-01

    Current research in the field of positron emission tomography (PET) focuses on improving the sensitivity of the scanner with thicker detectors, extended axial field-of-view, and time-of-flight (TOF) capability. These create the need for depth-of-interaction (DOI) encoding to correct parallax errors. We have proposed a method to encode DOI using phosphor-coated crystals. Our initial work using photomultiplier tubes (PMTs) demonstrated the possibilities of the proposed method, however, a major limitation of PMTs for this application is poor quantum efficiency in yellow light, corresponding to the wavelengths of the converted light by the phosphor coating. In contrast, the red-green-blue-high-density (RGB-HD) silicon photomultipliers (SiPMs) have a high photon detection efficiency across the visible spectrum. Excellent coincidence resolving time (CRT; [Formula: see text]) was obtained by coupling RGB-HD SiPMs and [Formula: see text] lutetium fine silicate crystals coated on a third of one of their lateral sides. Events were classified in three DOI bins ([Formula: see text] width) with an average sensitivity of 83.1%. A CRT of [Formula: see text] combined with robust DOI encoding is a marked improvement in the phosphor-coated approach that we pioneered. For the first time, we read out these crystals with SiPMs and clearly demonstrated the potential of the RGB-HD SiPMs for this TOF-DOI PET detector.

  20. Test of scintillator bars coupled to Silicon Photomultipliers for a charged particle tracking device

    Science.gov (United States)

    Cecchini, S.; D'Antone, I.; Esposti, L. Degli; Lax, I.; Mandrioli, G.; Mauri, N.; Pasqualini, L.; Patrizii, L.; Pozzato, M.; Sirri, G.; Tenti, M.

    2017-02-01

    This work is the first step in the implementation of a tracking detector for instrumenting a light spectrometer to study O(1 GeV) νμ CC interactions. A spatial resolution of O(1 mm) is required for the precise determination of momentum and charge of muons produced in such interactions. A tracking system prototype composed of planes of scintillator bars coupled to Silicon Photomultipliers in analog mode readout has been developed. The devised system provides a spatial resolution of better than 2 mm in reconstructing muon tracks. Results obtained in laboratory tests and with cosmic ray muons are discussed.

  1. Characterization and Optimization of silicon photomultipliers for the development of intraoperative beta probes

    Energy Technology Data Exchange (ETDEWEB)

    Hudin, N.; Pinot, L. [Laboratoire Imagerie et Modelisation en Neurobiologie et Cancerologie (UMR 8165), Campus d' Orsay, IN2P3-CNRS, 91406 Orsay Cedex (France); Dinu, N. [Laboratoire de l' Accelerateur Lineaire, IN2P3-CNRS, 91898 Orsay (France); Charon, Y. [Laboratoire Imagerie et Modelisation en Neurobiologie et Cancerologie (UMR 8165), Campus d' Orsay, IN2P3-CNRS, 91406 Orsay Cedex (France); Puill, V. [Laboratoire de l' Accelerateur Lineaire, IN2P3-CNRS, 91898 Orsay (France); Janvier, B. [Laboratoire Imagerie et Modelisation en Neurobiologie et Cancerologie (UMR 8165), Campus d' Orsay, IN2P3-CNRS, 91406 Orsay Cedex (France); Chaumat, V. [Laboratoire de l' Accelerateur Lineaire, IN2P3-CNRS, 91898 Orsay (France); Duval, M.-A.; Abi Haidar, D.; Siebert, R. [Laboratoire Imagerie et Modelisation en Neurobiologie et Cancerologie (UMR 8165), Campus d' Orsay, IN2P3-CNRS, 91406 Orsay Cedex (France); Menard, L., E-mail: menard@imnc.in2p3.fr [Laboratoire Imagerie et Modelisation en Neurobiologie et Cancerologie (UMR 8165), Campus d' Orsay, IN2P3-CNRS, 91406 Orsay Cedex (France)

    2012-12-11

    This work reports the results of a comprehensive study aiming to characterize and optimize the performances of Silicon Photomultipliers (SiPM) as photodetectors for intraoperative beta detection of radiolabeled tumor tissues. In that purpose, we focused our measurements on the influence of temperature and operating voltage on dark noise (count rate and amplitude distribution), absolute photon detection efficiency and total gain of different SiPM devices from Hamamatsu. The impact of these parameters on the overall beta sensitivity of SiPM-based scintillation detectors was quantified as a function of the intensity of the incident light following a simple physical model that is shown to correspond well with measurements.

  2. Calibration of photomultipliers and initial adjustment of the LHCb Electromagnetic Calorimeter for pilot LHC runs

    CERN Document Server

    Machikhiliyan, Irina

    2013-01-01

    The procedure for the initial adjustment of the LHCb ECAL energy scale is described. The calibration technique to determine the gains of photomultipliers in situ is discussed in details, including its technical implementation and the studies on possible systematic effects. Finally, the di-photon invariant mass distributions from early data collected in the end of 2009 in the course of the LHC start-up are presented, proving the sufficient level of the initial cell-to-cell intercalibration to detect clear signal from $\\pi^0 \\to \\gamma \\gamma$ decays.

  3. Single photon timing resolution and detection efficiency of the IRST silicon photo-multipliers

    Energy Technology Data Exchange (ETDEWEB)

    Collazuol, G. [Scuola Normale Superiore, 56127 Pisa (Italy); INFN Sezione di Pisa, 56127 Pisa (Italy)], E-mail: gianmaria.collazuol@pi.infn.it; Ambrosi, G. [INFN Sezione di Perugia, 06123 Perugia (Italy); Boscardin, M. [Fondazione Bruno Kessler - IRST, Divisione Microsistemi, 38050 Trento (Italy); Corsi, F. [DEE-Politecnico di Bari and INFN Sezione di Bari, 70125 Bari (Italy); Dalla Betta, G.F. [INFN Sezione di Padova, Gruppo Collegato di Trento, 38050 Trento (Italy); Del Guerra, A. [INFN Sezione di Pisa, 56127 Pisa (Italy); Dipartimento di Fisica, Universita di Pisa, 56127 Pisa (Italy); Dinu, N. [INFN Sezione di Padova, Gruppo Collegato di Trento, 38050 Trento (Italy); Galimberti, M. [Intense Laser Irradiation Laboratory, IPCF-CNR, 56127 Pisa (Italy); Giulietti, D. [INFN Sezione di Pisa, 56127 Pisa (Italy); Dipartimento di Fisica, Universita di Pisa, 56127 Pisa (Italy); Intense Laser Irradiation Laboratory, IPCF-CNR, 56127 Pisa (Italy); Gizzi, L.A.; Labate, L. [INFN Sezione di Pisa, 56127 Pisa (Italy); Intense Laser Irradiation Laboratory, IPCF-CNR, 56127 Pisa (Italy); Llosa, G.; Marcatili, S. [INFN Sezione di Pisa, 56127 Pisa (Italy); Dipartimento di Fisica, Universita di Pisa, 56127 Pisa (Italy); Morsani, F. [INFN Sezione di Pisa, 56127 Pisa (Italy); Piemonte, C.; Pozza, A. [Fondazione Bruno Kessler - IRST, Divisione Microsistemi, 38050 Trento (Italy); Zaccarelli, L. [INFN Sezione di Pisa, 56127 Pisa (Italy); Zorzi, N. [Fondazione Bruno Kessler - IRST, Divisione Microsistemi, 38050 Trento (Italy)

    2007-10-21

    Silicon photo-multipliers (SiPM) consist in matrices of tiny, passive quenched avalanche photo-diode cells connected in parallel via integrated resistors and operated in Geiger mode. Novel types of SiPM are being developed at FBK-IRST (Trento, Italy). Despite their classical shallow junction n-on-p structure the devices are unique in their enhanced photo-detection efficiency (PDE) for short-wavelengths and in their low level of dark rate and excess noise factor. After a summary of the extensive SiPM characterization we will focus on the study of PDE and the single photon timing resolution.

  4. Geant4 simulation of optical photon transport in scintillator tile with direct readout by silicon photomultiplier

    Science.gov (United States)

    Korpachev, S.; Chadeeva, M.

    2017-01-01

    The direct coupling of silicon photomultiplier to the scintillator tile is considered to be the main option for active elements of the highly granular hadron calorimeter developed for future linear collider experiments. In this study, the response of the scintillator-SiPM system to minimum ionising particles was simulated using the optical photon transport functionality available in the Geant4 package. The uniformity of response for both flat tile and tile with dimple was estimated from the simulations and compared to the experimental results obtained in the previous studies.

  5. Time-domain diffuse optical tomography using silicon photomultipliers: feasibility study.

    Science.gov (United States)

    Di Sieno, Laura; Zouaoui, Judy; Hervé, Lionel; Pifferi, Antonio; Farina, Andrea; Martinenghi, Edoardo; Derouard, Jacques; Dinten, Jean-Marc; Mora, Alberto Dalla

    2016-11-01

    Silicon photomultipliers (SiPMs) have been very recently introduced as the most promising detectors in the field of diffuse optics, in particular due to the inherent low cost and large active area. We also demonstrate the suitability of SiPMs for time-domain diffuse optical tomography (DOT). The study is based on both simulations and experimental measurements. Results clearly show excellent performances in terms of spatial localization of an absorbing perturbation, thus opening the way to the use of SiPMs for DOT, with the possibility to conceive a new generation of low-cost and reliable multichannel tomographic systems.

  6. Reconstruction of scintillations coordinates in cylindrical large detector with radial arrangement of photomultipliers

    CERN Document Server

    Alekseev, V M; Verbitskij, V S; Verbitskij, S S; Lapik, M A; Tselebrovskij, A N; Lapik, A M; Rusakov, A V; Savopulo, M L; Smirnov, V V; Chubarov, M N

    2002-01-01

    Paper describes algorithm to calculate scintillation coordinates elaborated for a coordinate-sensitive large detector based on liquid scintillator with radial arrangement of nine FEU-174 photomultipliers. Paper contains the simulation results of coordinate resolution dependence in detector centre on energy of gamma-quanta within 0.2-8 MeV range. Using this algorithm one processed the experimental data obtained with application of sup 6 sup 0 Co gamma-radiation source and the results of determination of scintillation coordinates for gamma-quanta beam. The accuracy of coordinate determination in detector centre when applying the descried algorithm constitutes approx 10 mm

  7. Photoelectron Yields of Scintillation Counters with Embedded Wavelength-Shifting Fibers Read Out With Silicon Photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Artikov, Akram; et al.

    2017-09-19

    Photoelectron yields of extruded scintillation counters with titanium dioxide coating and embedded wavelength shifting fibers read out by silicon photomultipliers have been measured at the Fermilab Test Beam Facility using 120\\,GeV protons. The yields were measured as a function of transverse, longitudinal, and angular positions for a variety of scintillator compositions and reflective coating mixtures, fiber diameters, and photosensor sizes. Timing performance was also studied. These studies were carried out by the Cosmic Ray Veto Group of the Mu2e collaboration as part of their R\\&D program.

  8. A Pseudoscalar Hybrid Meson?

    CERN Document Server

    Page, P R

    1996-01-01

    New experimental information on the non--exotic J^{PC} = 0^{-+} isovector seen at 1.8 GeV by VES yields convincing evidence of its excited gluonic (hybrid) nature when a critical study of alternative quarkonium assignments is made in the context of ^3 P_0 decay by flux--tube breaking. Production of this gluonic excitation via meson exchange is promising, although its two photon production vanishes.

  9. Intercostal drainage tube or intracardiac drainage tube?

    Directory of Open Access Journals (Sweden)

    N Anitha

    2016-01-01

    Full Text Available Although insertion of chest drain tubes is a common medical practice, there are risks associated with this procedure, especially when inexperienced physicians perform it. Wrong insertion of the tube has been known to cause morbidity and occasional mortality. We report a case where the left ventricle was accidentally punctured leading to near-exsanguination. This report is to highlight the need for experienced physicians to supervise the procedure and train the younger physician in the safe performance of the procedure.

  10. Photomultiplier voltage setting: possible important source of variability in molecular equivalents of soluble fluorochrome (MESF) calculation?

    Science.gov (United States)

    Rigolin, G M; Lanza, F; Castoldi, G

    1995-08-01

    We evaluated the effect of flow cytometer photomultiplier (PMT) voltage setting on molecular equivalents of soluble fluorochrome (MESF) calculation by using two different quantitative microbead calibrating kits as calibrating standards and a third one as an unknown testing sample of stable intensity of fluorescence. Based on the analysis of residual values derived from linear regression and on the determinations of the resolution index, we demonstrated that, on a FACScan instrument, the window of photomultiplier setting for fluorescein isothiocyanate (FITC) fluorescence determinations is 590-670 V. However, the best region was in the range of 610-650 V. Within the 590-670 PMT voltage region, the evaluation of the same testing sample at different PMT voltages, at 590 V, gave MESF percentage differences of 15% and 13% on the two lower unknown standards of intensity compared to the values obtained at the nearby 630 V setting. In the analyzed PMT region, logarithmic amplifier response was globally maintained, whereas evaluation of the same unknown testing sample in both linear (Lin) and logarithmic (Log) amplification demonstrated (at the higher intensities of fluorescence) Log-Lin minimal differences within the 610-650 PMT voltage range. According to our data, it can be stated that PMT voltages between 610 and 650 provide the best instrument performances and that PMT setting may be proposed as a source of variability in MESF calculation that deserves a careful evaluation in quality-control trials.

  11. Silicon photomultipliers for improved detection of low light levels in miniature near-infrared spectroscopy instruments.

    Science.gov (United States)

    Zimmermann, R; Braun, F; Achtnich, T; Lambercy, O; Gassert, R; Wolf, M

    2013-05-01

    Silicon photomultipliers are novel solid state photodetectors that recently became commercially available. The goal of this paper was to investigate their suitability for low light level detection in miniaturized functional near-infrared spectroscopy instruments. Two measurement modules with a footprint of 26×26 mm(2) were built, and the signal-to-noise ratio was assessed for variable source-detector separations between 25 and 65 mm on phantoms with similar optical properties to those of a human head. These measurements revealed that the signal-to-noise ratio of the raw signal was superior to an empirically derived design requirement for source-detector separations up to 50 mm. An arterial arm occlusion was also performed on one of the authors in vivo, to induce reproducible hemodynamic changes which confirmed the validity of the measured signals. The proposed use of silicon photomultipliers in functional near-infrared spectroscopy bears large potential for future development of precise, yet compact and modular instruments, and affords improvements of the source-detector separation by 67% compared to the commonly used 30 mm.

  12. Performance of CATIROC: ASIC for smart readout of large photomultiplier arrays

    Science.gov (United States)

    Blin, S.; Callier, S.; Conforti Di Lorenzo, S.; Dulucq, F.; De La Taille, C.; Martin-Chassard, G.; Seguin-Moreau, N.

    2017-03-01

    CATIROC (Charge And Time Integrated Read Out Chip) is a complete read-out chip manufactured in AustriaMicroSystem (AMS) SiGe 0.35 μm technology, designed to read arrays of 16 photomultipliers (PMTs). It is an upgraded version of PARISROC2 [1] designed in 2010 in the context of the PMm2 (square meter PhotoMultiplier) project [2]. CATIROC is a SoC (System on Chip) that processes analog signals up to the digitization and sparsification to reduce the cost and cable number. The ASIC is composed of 16 independent channels that work in triggerless mode, auto-triggering on the single photo-electron. It provides a charge measurement up to 400 photoelectrons (70 pC) on two scales of 10 bits and a timing information with an accuracy of 200 ps rms. The ASIC was sent for fabrication in February 2015 and then received in September 2015. It is a good candidate for two Chinese projects (LHAASO and JUNO). The architecture and the measurements will be detailed in the paper.

  13. Development of high performance readout ASICs for silicon photomultipliers (SiPMs)

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Wei

    2012-07-24

    Silicon Photomultipliers (SiPMs) are novel kind of solid state photon detectors with extremely high photon detection resolution. They are composed of hundreds or thousands of avalanche photon diode pixels connected in parallel. These avalanche photon diodes are operated in Geiger Mode. SiPMs have the same magnitude of multiplication gain compared to the conventional photomultipliers (PMTs). Moreover, they have a lot of advantages such as compactness, relatively low bias voltage and magnetic field immunity etc. Special readout electronics are required to preserve the high performance of the detector. KLauS and STiC are two CMOS ASIC chips designed in particular for SiPMs. KLauS is used for SiPM charge readout applications. Since SiPMs have a much larger detector capacitance compared to other solid state photon detectors such as PIN diodes and APDs, a few special techniques are used inside the chip to make sure a descent signal to noise ratio for pixel charge signal can be obtained. STiC is a chip dedicated to SiPM time-of-flight applications. High bandwidth and low jitter design schemes are mandatory for such applications where time jitter less than tens of picoseconds is required. Design schemes and error analysis as well as measurement results are presented in the thesis.

  14. In-depth study of single photon time resolution for the Philips digital silicon photomultiplier

    Science.gov (United States)

    Liu, Z.; Gundacker, S.; Pizzichemi, M.; Ghezzi, A.; Auffray, E.; Lecoq, P.; Paganoni, M.

    2016-06-01

    The digital silicon photomultiplier (SiPM) has been commercialised by Philips as an innovative technology compared to analog silicon photomultiplier devices. The Philips digital SiPM, has a pair of time to digital converters (TDCs) connected to 12800 single photon avalanche diodes (SPADs). Detailed measurements were performed to understand the low photon time response of the Philips digital SiPM. The single photon time resolution (SPTR) of every single SPAD in a pixel consisting of 3200 SPADs was measured and an average value of 85 ps full width at half maximum (FWHM) was observed. Each SPAD sends the signal to the TDC with different signal propagation time, resulting in a so called trigger network skew. This distribution of the trigger network skew for a pixel (3200 SPADs) has been measured and a variation of 50 ps FWHM was extracted. The SPTR of the whole pixel is the combination of SPAD jitter, trigger network skew, and the SPAD non-uniformity. The SPTR of a complete pixel was 103 ps FWHM at 3.3 V above breakdown voltage. Further, the effect of the crosstalk at a low photon level has been studied, with the two photon time resolution degrading if the events are a combination of detected (true) photons and crosstalk events. Finally, the time response to multiple photons was investigated.

  15. Characterization studies of Silicon Photomultipliers and crystals matrices for a novel time of flight PET detector

    CERN Document Server

    Auffray, Etiennette; Cortinovis, Daniele; Doroud, Katayoun; Garutti, Erika; Lecoq, Paul; Liu, Zheng; Martinez, Rosana; Paganoni, Marco; Pizzichemi, Marco; Silenzi, Alessandro; Xu, Chen; Zvolský, Milan

    2015-01-01

    This paper describes the characterization of crystal matrices and silicon photomultiplier arrays for a novel Positron Emission Tomography (PET) detector, namely the external plate of the EndoTOFPET-US system. The EndoTOFPET-US collaboration aims to integrate Time-Of-Flight PET with ultrasound endoscopy in a novel multimodal device, capable to support the development of new biomarkers for prostate and pancreatic tumors. The detector consists in two parts: a PET head mounted on an ultrasound probe and an external PET plate. The challenging goal of 1 mm spatial resolution for the PET image requires a detector with small crystal size, and therefore high channel density: 4096 LYSO crystals individually readout by Silicon Photomultipliers (SiPM) make up the external plate. The quality and properties of these components must be assessed before the assembly. The dark count rate, gain, breakdown voltage and correlated noise of the SiPMs are measured, while the LYSO crystals are evaluated in terms of light yield and en...

  16. Time resolution of the plastic scintillator strips with matrix photomultiplier readout for J-PET tomograph

    CERN Document Server

    Moskal, P; Alfs, D; Bednarski, T; Białas, P; Czerwiński, E; Gajos, A; Giergiel, K; Gorgol, M; Jasińska, B; Kamińska, D; Kapłon, Ł; Korcyl, G; Kowalski, P; Kozik, T; Krzemień, W; Kubicz, E; Niedźwiecki, Sz; Pałka, M; Raczyński, L; Rudy, Z; Sharma, N G; Słomski, A; Silarski, M; Strzelecki, A; Wieczorek, A; Wiślicki, W; Witkowski, P; Zieliński, M; Zoń, N

    2016-01-01

    Recent tests of a single module of the Jagiellonian Positron Emission Tomography system (J-PET) consisting of 30 cm long plastic scintillator strips have proven its applicability for the detection of annihilation quanta (0.511 MeV) with a coincidence resolving time (CRT) of 0.266 ns. The achieved resolution is almost by a factor of two better with respect to the current TOF-PET detectors and it can still be improved since, as it is shown in this article, the intrinsic limit of time resolution for the determination of time of the interaction of 0.511 MeV gamma quanta in plastic scintillators is much lower. As the major point of the article, a method allowing to record timestamps of several photons, at two ends of the scintillator strip, by means of matrix of silicon photomultipliers (SiPM) is introduced. As a result of simulations, conducted with the number of SiPM varying from 4 to 42, it is shown that the improvement of timing resolution saturates with the growing number of photomultipliers, and that the 2 x...

  17. Shock tube measurements of the optical absorption of triatomic carbon, C3

    Science.gov (United States)

    Jones, J. J.

    1977-01-01

    The spectral absorption of C3 has been measured in a shock tube using a test gas mixture of acetylene diluted with argon. The absorption of a pulsed xenon light source was measured by means of eight photomultiplier channels to a spectrograph and an accompanying drum camera. The postshock test gas temperature and pressure were varied over the range 3300-4300 K and 0.36 to 2.13 atmospheres, respectively. The results showed appreciable absorption from C3 for the wavelength range 300 to 540 nanometers. The computed electronic oscillator strength varied from 0.12 to 0.06 as a function of temperature.

  18. Pulse Tube Refrigerator

    Science.gov (United States)

    Matsubara, Yoichi

    The pulse tube refrigerator is one of the regenerative cycle refrigerators such as Stirling cycle or Gifford-McMahon cycle which gives the cooling temperature below 150 K down to liquid helium temperature. In 1963, W. E. Gifford invented a simple refrigeration cycle which is composed of compressor, regenerator and simple tube named as pulse tube which gives a similar function of the expander in Stirling or Gifford-McMahon cycle. The thermodynamically performance of this pulse tube refrigerator is inferior to that of other regenerative cycles. In 1984, however, Mikulin and coworkers made a significant advance in pulse tube configuration called as orifice pulse tube. After this, several modifications of the pulse tube hot end configuration have been developed. With those modifications, the thermodynamic performance of the pulse tube refrigerator became the same order to that of Stirling and Gifford-McMahon refrigerator. This article reviews the brief history of the pulse tube refrigerator development in the view point of its thermodynamically efficiency. Simplified theories of the energy flow in the pulse tube have also been described.

  19. (Hybrid) Baryons Quantum Numbers and Adiabatic Potentials

    CERN Document Server

    Page, P R

    1999-01-01

    We construct (hybrid) baryons in the flux-tube model of Isgur and Paton. In the limit of adiabatic quark motion, we build proper eigenstates of orbital angular momentum and indicate the flavour, spin, chirality and J^P of (hybrid) baryons. The adiabatic potential is calculated as a function of the quark positions.

  20. Domestic Development of Single-Photon Emission Computed Tomography (SPECT) Unit with Detector based on Silicon Photomultipliers

    Science.gov (United States)

    Grishakov, S.; Ryzhikova, O.; Sergienko, V.; Ansheles, A.; Novikov, S.

    2017-01-01

    The idea of creating a single-photon emission computed tomography unit with solid-state photomultipliers is not new [1], as the problems of analog-to-digital conversion with a lot of noise and a wide range of values of intrinsic spatial resolution of the detector in a center and relevant fields of view could not be solved by means of gamma-camera detector architectures based on vacuum photomultipliers. This paper offers a new SPECT imaging solution that is free from these problems.

  1. Development of small-animal PET prototype using silicon photomultiplier (SiPM): initial results of phantom and animal imaging studies.

    Science.gov (United States)

    Kwon, Sun Il; Lee, Jae Sung; Yoon, Hyun Suk; Ito, Mikiko; Ko, Guen Bae; Choi, Jae Yeon; Lee, Sung-Hyuk; Chan Song, In; Jeong, Jae Min; Lee, Dong Soo; Hong, Seong Jong

    2011-04-01

    Silicon photomultiplier (SiPM; also called a Geiger-mode avalanche photodiode) is a promising semiconductor photosensor in PET and PET/MRI because it is intrinsically MRI-compatible and has internal gain and timing properties comparable to those of a photomultiplier tube. In this study, we have developed a small-animal PET system using SiPMs and lutetium gadolinium oxyorthosilicate (LGSO) crystals and performed physical evaluation and animal imaging studies to show the feasibility of this system. The SiPM PET system consists of 8 detectors, each of which comprises 2 × 6 SiPMs and 4 × 13 LGSO crystals. Each crystal has dimensions of 1.5 × 1.5 × 7 mm. The crystal face-to-face diameter and axial field of view are 6.0 cm and 6.5 mm, respectively. Bias voltage is applied to each SiPM using a finely controlled voltage supply because the gain of the SiPM strongly depends on the supply voltage. The physical characteristics were studied by measuring energy resolution, sensitivity, and spatial resolution. Various mouse and rat images were obtained to study the feasibility of the SiPM PET system in in vivo animal studies. Reconstructed PET images using a maximum-likelihood expectation maximization algorithm were coregistered with animal CT images. All individual LGSO crystals within the detectors were clearly distinguishable in flood images obtained by irradiating the detector using a (22)Na point source. The energy resolution for individual crystals was 25.8% ± 2.6% on average for 511-keV photopeaks. The spatial resolution measured with the (22)Na point source in a warm background was 1.0 mm (2 mm off-center) and 1.4 mm (16 mm off-center) when the maximum-likelihood expectation maximization algorithm was applied. A myocardial (18)F-FDG study in mice and a skeletal (18)F study in rats demonstrated the fine spatial resolution of the scanner. The feasibility of the SiPM PET system was also confirmed in the tumor images of mice using (18)F-FDG and (68)Ga-RGD and in the

  2. Heated Tube Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Heated Tube Facility at NASA GRC investigates cooling issues by simulating conditions characteristic of rocket engine thrust chambers and high speed airbreathing...

  3. Fuel nozzle tube retention

    Energy Technology Data Exchange (ETDEWEB)

    Cihlar, David William; Melton, Patrick Benedict

    2017-02-28

    A system for retaining a fuel nozzle premix tube includes a retention plate and a premix tube which extends downstream from an outlet of a premix passage defined along an aft side of a fuel plenum body. The premix tube includes an inlet end and a spring support feature which is disposed proximate to the inlet end. The premix tube extends through the retention plate. The spring retention feature is disposed between an aft side of the fuel plenum and the retention plate. The system further includes a spring which extends between the spring retention feature and the retention plate.

  4. Optimization and experiment on pollination tube of collision and air-blowing hybrid rice pollination machine%“击穗气吹式”杂交水稻制种授粉机授粉管优化与试验

    Institute of Scientific and Technical Information of China (English)

    王永维; 唐晨; 王俊; 胡金冰; 任奇锋

    2015-01-01

    为克服人工授粉效率低、花粉分布均匀性差等缺点,实现杂交水稻制种机械化授粉,该文设计并试制了击穗-气吹式杂交水稻授粉机,利用CFD数值仿真技术对该机气吹嘴式和气吹孔式2种授粉管的气流场分布进行数值模拟,测试了不同流量下授粉管各吹气孔流速;然后进行田间授粉试验,采用重力玻片法检测了授粉机授粉与人工授粉时花粉分布。结果表明,在相同进气口速度条件下,吹孔式授粉管外部分气吹孔气流倾斜,授粉管外侧存在气流未达到的死区;气嘴式授粉管外侧各气吹嘴气流方向基本一致,可为气流授粉提供均匀稳定的气流场,吹嘴式授粉管是较理想的授粉管型式;在进气口风速为5.4、10.0和13.5 m/s时,吹嘴式授粉管各气吹嘴出口气流速度的模拟与实测值沿授粉管的变化趋势一致,气吹嘴出口气流速度模拟值与实测值的平均误差分别为2.14%、2.40%和3.43%,气流沿授粉管分布的均匀性变异系数分别为14.76%、15.93%和16.31%。田间授粉试验表明,在气吹嘴出口平均流速为7.3 m/s时,该机的每行花粉量及各母本行花粉量分布的均匀性上均优于人工授粉,授粉效率高于人工授粉法,为杂交水稻制种机械化授粉提供了实用机型。%Pollination is the key process in the hybrid rice seed production. To realizing mechanical pollination of hybrid rice, this paper designed and trial-manufactured a hybrid rice pollination machine combined collision and air-blowing method. Flow field distribution of two types of the pollination tube on the machine, including air-blow nozzle type and air-blow hole type were simulated using CFD technology. And the flow velocity out of each nozzle or hole on pollination tube was measured, and the pollination experiments in the paddy field using pollination machine prototype were carried out. In the experiment, the pollen

  5. Steam generator tube failures

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, P.E.; Shah, V.N.; Ward, L.W.; Ellison, P.G.

    1996-04-01

    A review and summary of the available information on steam generator tubing failures and the impact of these failures on plant safety is presented. The following topics are covered: pressurized water reactor (PWR), Canadian deuterium uranium (CANDU) reactor, and Russian water moderated, water cooled energy reactor (VVER) steam generator degradation, PWR steam generator tube ruptures, the thermal-hydraulic response of a PWR plant with a faulted steam generator, the risk significance of steam generator tube rupture accidents, tubing inspection requirements and fitness-for-service criteria in various countries, and defect detection reliability and sizing accuracy. A significant number of steam generator tubes are defective and are removed from service or repaired each year. This wide spread damage has been caused by many diverse degradation mechanisms, some of which are difficult to detect and predict. In addition, spontaneous tube ruptures have occurred at the rate of about one every 2 years over the last 20 years, and incipient tube ruptures (tube failures usually identified with leak detection monitors just before rupture) have been occurring at the rate of about one per year. These ruptures have caused complex plant transients which have not always been easy for the reactor operators to control. Our analysis shows that if more than 15 tubes rupture during a main steam line break, the system response could lead to core melting. Although spontaneous and induced steam generator tube ruptures are small contributors to the total core damage frequency calculated in probabilistic risk assessments, they are risk significant because the radionuclides are likely to bypass the reactor containment building. The frequency of steam generator tube ruptures can be significantly reduced through appropriate and timely inspections and repairs or removal from service.

  6. Initial results of simultaneous PET/MRI experiments with an MRI-compatible silicon photomultiplier PET scanner

    National Research Council Canada - National Science Library

    Yoon, Hyun Suk; Ko, Guen Bae; Kwon, Sun Il; Lee, Chan Mi; Ito, Mikiko; Chan Song, In; Lee, Dong Soo; Hong, Seong Jong; Lee, Jae Sung

    2012-01-01

    ...). However, the silicon photomultiplier (SiPM), also called the Geiger-mode APD, is gaining attention in the development of the next generation of PET/MRI systems because the SiPM has much better performance than the APD...

  7. Study of timing performance of Silicon Photomultiplier and application for a Cherenkov detector

    CERN Document Server

    Ahmed, G S M; Marton, J; Suzuki, K

    2010-01-01

    Silicon photomultipliers are very versatile photo detectors due to their high photon detection efficiency, fast response, single photon counting capability, high amplification, and their insensitivity to magnetic fields. At our institute we are studying the performance of these photo detectors at various operating conditions. On the basis of the experience in the laboratory we built a prototype of a timing Cherenkov detector consisting of a quartz radiator with two $3\\times 3$ mm$^2$ MPPCs S10362-33-100C from Hamamatsu Photonics as photodetectors. The MPPC sensors were operated with Peltier cooling to minimize thermal noise and to avoid gain drifts. The test measurements at the DA$\\Phi$NE Beam-Test Facility (BTF) at the Laboratori Nazionali di Frascati (LNF) with pulsed 490 MeV electrons and the results on timing performance with Cherenkov photons are presented.

  8. Analysis of Silicon Photomultiplier Detector Waveforms from Cosmic Rays using Digital Signal Processing Techniques

    Science.gov (United States)

    Castro, Juan; Zavala, Favian; Niduaza, Rexavalmar; Wedel, Zachary; Fan, Sewan; Ritt, Stefan; Fatuzzo, Laura

    2014-03-01

    Silicon photomultiplier detectors exhibit high gain, low operating voltage, are insensitive to magnetic fields, and can detect light at the single photon level, making them very attractive for applications in fields such as particle physics, astrophysics, and medical physics. However, they exhibit effects that may prevent their optimal operation, including thermally induced high dark count rate, after pulse effects, and cross talk produced from photons in nearby pixels. In this presentation, we describe our coincidence setup using two scintillator pads and a Hamamatsu multipixel photon counter (MPPC) to gather cosmic ray produced signal pulses, and our methods of analysis for the detector waveforms. In particular, we discuss our methods of digitization, software implementation of low pass and Gaussian type filters, and the application of a domino ring sampler (DRS4) digitizing board to obtain signal waveforms to determine the operating characteristics for these detectors. Department of Education grant number P031S90007.

  9. KLauS – A charge readout and fast discrimination chip for silicon photomultipliers

    CERN Document Server

    Dorn, M; Shen, W; Sidlauskas, G; Schultz-Coulon, H.C

    2012-01-01

    photomultipliers. The chip has been designed for the application in the analog hadronic calorimeter developed by the CALICE collaboration for the next linear collider experiment . To address the severe power constraints introduced by the highly granular design of the calorimeter, the chip has been designed for low power consumption while maintaining the high dynamic range and timing precision required by the experiment. In addition, a power gating scheme has been implemented to further decrease the average power consumption. For a duty cycle of 1% a value of 25µW per channel is achieved without affecting the readout capabilities of the chip. The chip has been designed in the 0.35µm SiGe technology and provides a low power readout channel for SiPMs with low gain for the input stage of the existing readout chip SPIROC. The analog channel of KLauS will be implemented in a future version of the SPIROC chip.

  10. Application of scintillating properties of liquid xenon and silicon photomultiplier technology to medical imaging

    Science.gov (United States)

    Gomez-Cadenas, J. J.; Benlloch-Rodriguez, J. M.; Ferrario, Paola

    2016-04-01

    We describe a new positron emission time-of-flight apparatus using liquid xenon. The detector is based in a liquid xenon scintillating cell. The cell shape and dimensions can be optimized depending on the intended application. In its simplest form, the liquid xenon scintillating cell is a box in which two faces are covered by silicon photomultipliers and the others by a reflecting material such as Teflon. It is a compact, homogenous and highly efficient detector which shares many of the desirable properties of monolithic crystals, with the added advantage of high yield and fast scintillation offered by liquid xenon. Our initial studies suggest that good energy and spatial resolution comparable with that achieved by lutetium oxyorthosilicate crystals can be obtained with a detector based in liquid xenon scintillating cells. In addition, the system can potentially achieve an excellent coincidence resolving time of better than 100 ps.

  11. The upgrade of the CMS hadron calorimeter with silicon 5 photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Strobbe, N. [Fermilab

    2016-09-01

    The upgrade of the hadron calorimeter of the CMS experiment at the CERN Large Hadron Collider is currently underway. The endcap sections will be upgraded in the winter of 2016–2017 and the barrel sections during the second LHC long shutdown in 2019. The existing photosensors will be replaced with about 16 000 new silicon photomultipliers (SiPMs), resulting in the first large installation of SiPMs in a radiation environment. All associated front-end electronics will also be upgraded. This paper discusses the motivation for the upgrade and provides a description 17 of the new system, including the SiPMs with associated control electronics and the front-end readout cards.

  12. New Photonis XP20D0 photomultiplier for fast timing in nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Moszynski, M. [Soltan Institute for Nuclear Studies, PL 05-400 Swierk-Otwock (Poland)]. E-mail: marek@ipj.gov.pl; Gierlik, M. [Soltan Institute for Nuclear Studies, PL 05-400 Swierk-Otwock (Poland); Kapusta, M. [Soltan Institute for Nuclear Studies, PL 05-400 Swierk-Otwock (Poland); Nassalski, A. [Soltan Institute for Nuclear Studies, PL 05-400 Swierk-Otwock (Poland); Szczesniak, T. [Soltan Institute for Nuclear Studies, PL 05-400 Swierk-Otwock (Poland); Fontaine, Ch. [Photonis. Av. Roger Roncier, B.P. 520, F 19106 Brive La Gaillarde Cedex (France); Lavoute, P. [Photonis. Av. Roger Roncier, B.P. 520, F 19106 Brive La Gaillarde Cedex (France)

    2006-11-01

    Growing interest in the time-of-flight positron emission tomography (TOF PET) prompts the study of a new Photonis XP20D0 photomultiplier, equipped with a screening grid at the anode, in application to a fast timing with LSO and LaBr{sub 3} crystals. The high time resolution of 200{+-}4 and 210{+-}4 ps was obtained for 511 keV annihilation quanta using LaBr{sub 3} and LSO crystals in the coincidence experiment with a small BaF{sub 2} crystal, respectively. It reflects an importance of the grid and high quantum efficiency of the XP20D0. A high-time resolution observed in the present experiments makes good prospects for a development of TOF PET.

  13. Scintillators with Silicon Photomultiplier Readout for Timing Measurements in Hadronic Showers

    CERN Document Server

    Soldner, Christian

    2011-01-01

    The advent of silicon photomultipliers has enabled big advances in high energy physics instrumentation, for example by allowing the construction of extremely granular hadronic calorimeters with photon sensors integrated into small scintillator tiles. Direct coupling of the SiPM to the plastic scintillator, without use of wavelength shifting fibers, provides a fast detector response, making such devices well suited for precise timing measurements. We have constructed a setup consisting of 15 such scintillator tiles read out with fast digitizers with deep buffers to measure the time structure of signals in hadronic calorimeters. Specialized data reconstruction algorithms that allow the determination of the arrival time of individual photons by a detailed analysis of the recorded waveforms and that provide automatic calibration of the gain of the photon sensor, have been developed. We will discuss the experimental apparatus and the data analysis. In addition, we will report on first results obtained in a hadroni...

  14. Characterization and modeling of crosstalk and afterpulsing in Hamamatsu silicon photomultipliers

    CERN Document Server

    Rosado, Jaime

    2015-01-01

    The crosstalk and afterpulsing in Hamamatsu silicon photomultipliers, called Multi-Pixel Photon Counters (MPPCs), have been studied in depth. Several components of the correlated noise have been identified according to their different possible causes and their effects on the signal. In particular, we have distinguished between prompt and delayed crosstalk as well as between trap-assisted and hole-induced afterpulsing. The prompt crosstalk has been characterized through the pulse amplitude spectrum measured at dark conditions. The newest MPPC series, which incorporate isolating trenches between pixels, exhibit a very low prompt crosstalk, but a small component remains likely due to secondary photons reflected on the top surface of the device and photon-generated minority carriers diffusing in the silicon substrate. We present a meticulous procedure to characterize the afterpulsing and delayed crosstalk through the amplitude and delay time distributions of secondary pulses. Our results indicate that both noise ...

  15. The Strip Silicon Photo-Multiplier: An innovation for enhanced time and position measurement

    Science.gov (United States)

    Doroud, K.; Williams, M. C. S.; Yamamoto, K.

    2017-05-01

    There is considerable R&D concerning precise time measurement from a variety of detectors, and in particular for the Silicon PhotoMultiplier (SiPM). In this paper we discuss a new geometry for the SiPM in the form of a strip. A strip can be read out at both end, with each end coupled to an individual TDC (time to digital converter). The time difference is related to the position of the firing SPAD along the length of the strip, while the average of the two times gives the time of the hit. Results from the testing of the first prototype Strip SiPMs are presented in this paper.

  16. The silicon photomultipliers in the detector subsystems of the GlueX experiment

    Science.gov (United States)

    Somov, A.; Barbosa, F.; Tolstukhin, I.; Somov, S. V.; Berdnikov, V. V.

    2017-01-01

    The subsystem detectors of GlueX experiment use silicon photomultiplier (SiPM). Around five thousand SiPM’s in total uses in the detectors of experiment. The detectors operate in condition of load level 2MHz and up to 104 pixels «fired» with ∼0.3ns time resolution. The list of such detectors: the tagger microscope, the pair spectrometer, the start counter which surrounded the liquid hydrogen target; the electromagnetic barrel calorimeter to measure energy and direction of secondary photons comes from the target. We present the results of the time resolution measurements and the relaxation time measurements for two SiPM types in experimental conditions.

  17. A new imaging device based on UV scintillators and a large area gas photomultiplier

    Energy Technology Data Exchange (ETDEWEB)

    Sekiya, H., E-mail: sekiya@icrr.u-tokyo.ac.jp [Kamioka Observatory, Institute for Cosmic Ray Research, Univeristy of Tokyo, 456, Higashi-Mozumi Hida, Gifu 506-1205 (Japan); Kamioka Satellite, Institute for the Physics and Mathematics of the Universe, 456, Higashi-Mozumi Hida, Gifu 506-1205 (Japan); Ida, C.; Kubo, H.; Kurosawa, S.; Miuchi, K.; Tanimori, T.; Taniue, K. [Department of Physics, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake, Sakyo, Kyoto 606-8502 (Japan); Yoshikawa, A.; Yanagida, T.; Yokota, Y. [Institute of Multidisciplinary, Research for Advanced Materials, Tohoku University, 2-1-1, Katahira, Aoba, Sendai, Miyagi 980-8577 (Japan); Fukuda, K.; Ishizu, S.; Kawaguchi, N.; Suyama, T. [Tokuyama Corporation, 3-3-1, Shibuya, Shibuya, Tokyo 150-8383 (Japan)

    2011-05-15

    A new type high spatial resolution radiation detector based on a UV scintillator+a UV imaging gas photomultiplier is presented. The prototype UV detector consists of a 10 cmx10 cm {mu}PIC, 2 GEMs and a semitransparent CsI photocathode deposited on a MgF{sub 2} window. The effective photo-sensitive area is {phi}34 mm and the readouts are 400 {mu}m pitch strips. A newly developed 20 mm size LaF{sub 3}(Nd) crystal which emits 172 nm photons is coupled to the detector for the first step. The detector was tested in pulse mode operation with 5.5 MeV {alpha} particles from {sup 241}Am. The single photoelectrons were successfully detected and the images of the crystal shape were clearly obtained.

  18. A digital silicon photomultiplier with multiple time-to-digital converters

    Energy Technology Data Exchange (ETDEWEB)

    Garutti, Erika [University Hamburg (Germany); Silenzi, Alessandro [DESY, Hamburg (Germany); Xu, Chen [DESY, Hamburg (Germany); University Hamburg (Germany)

    2013-07-01

    A silicon photomultiplier (SiPM) with pixel level signal digitization and column-wise connected time-to-digital converters (TDCs) has been developed for an endoscopic Positron Emission Tomography (PET) detector. A digital SiPM has pixels consist of a single photon avalanche diode (SPAD) and circuit elements to optimize overall dark counts and temporal response. Compared with conventional analog SiPM, digital SiPM's direct signal route from SPAD to TDC improves single photon time resolution. In addition, using multiple TDCs can perform the statistical estimation of the time-of-arrival in multiple photon detection case such as readout of scintillation crystals. Characterization measurements of the prototype digital SiPM and a Monte-Carlo simulation to predict the timing performance of the PET detector are shown.

  19. High speed simultaneous measurement of pulse area and time-of-flight for photomultiplier signals

    Energy Technology Data Exchange (ETDEWEB)

    Hartouni, E.P.; Jensen, D.A.; Klima, B.; Kreisler, M.N.; Lee, S.; Markianos, K.; Nordberg, M.; Rabin, M.S.Z.; Uribe, J.; Wesson, D. (Dept. of Physics and Astronomy, Univ. Massachusetts, Amherst, MA (United States)); Church, M.; Gara, A.; Gottschalk, E.; Hylton, R.; Knapp, B.C.; Sippach, W.; Stern, B.; Wiencke, L. (Columbia Univ., Nevis Lab., Irvington-on-Hudson, NY (United States)); Christian, D.; Etchegoyen, M.C.B.; Gutierrez, G.; Holmes, S.; Strait, J.; Wehmann, A. (Fermilab, Batavia, IL (United States)); Avilez, C.; Correa, W.; Felix, J.; Flores, H.; Moreno, G.; Romero, M.; Sosa, M. (Inst. de Fisica, Univ. Guanajuato, Leon (Mexico)); Forbush, M.; Huson, F.R.; White, J.T.; Wightman, J.A. (Dept. of Physics, Texas A and M Univ., TX (United States))

    1992-06-15

    A modular system to provide high speed simultaneous measurements of pulse area and time-of-flight for photomultiplier signals is described. By requiring a minimum pulse size and a time-of-flight signal within a gate before recording either measurement, the system achieves several advantages over other techniques. In particular, since no time is wasted reading channels without useful information, read out speed is enhanced. The system permits accurate measurements at rates exceeding 10 MHz per channel and can be read out without excessive dead time at rates up to approximately 100 kHz. Data storage problems are also reduced. Both pulse area and time-of-flight are measured using 128 bins (7 bits). Costs are less than 40 US Dollar per channel. Other advantages and design features are discussed. (orig.).

  20. Ultrafast Readout of Scintillating Fibres Using Upgraded Position-Sensitive Photomultipliers

    CERN Multimedia

    2002-01-01

    % RD-17 \\\\ \\\\To design a high rate topological trigger device for the future DIRAC Experiment at CERN an extensive work is in progress on a scintillating-fibre detector using a position-sensitive photomultiplier. Several detector prototypes with different lengths ($<$~50~cm) of sensitive area have been tested at T7S~PS beam. \\\\ \\\\With 0.5~mm diameter fibres a spatial resolution of $\\sim$125~$\\mu$m was obtained with a detection efficiency higher than 95\\%. The time resolution is $\\sim$600~ps, and the track position is properly digitized in real time (about 10~ns) by multi-channel peak sensing circuit. Based on experimental data simulations were also performed a comparison of different types of front-end electronics for multi-channel readout.

  1. Hologram recording tubes

    Science.gov (United States)

    Rajchman, J. H.

    1973-01-01

    Optical memories allow extremely large numbers of bits to be stored and recalled in a matter of microseconds. Two recording tubes, similar to conventional image-converting tubes, but having a soft-glass surface on which hologram is recorded, do not degrade under repeated hologram read/write cycles.

  2. Silicon Photomultipliers and front-end electronics performance for Cherenkov Telescope Array camera development

    Science.gov (United States)

    Ambrosi, G.; Bissaldi, E.; Giglietto, N.; Giordano, F.; Ionica, M.; Paoletti, R.; Rando, R.; Simone, D.; Vagelli, V.

    2017-02-01

    In the last few years a number of efforts have been undertaken to develop new technology related to Silicon Photomultipliers (SiPMs). These photosensors consist of an array of identical Avalanche Photodiodes operating in Geiger mode and connected in parallel to a single output. The Italian Institute of Nuclear Physics (INFN) is involved in the R&D program Progetto Premiale Telescopi CHErenkov made in Italy (TECHE.it) to develop photosensors for a SiPM based camera that will be part of the Cherenkov Telescope Array (CTA) observatory. In this framework tests are ongoing on innovative devices suitable to detect Cherenkov light in the blue and near-UV wavelength region, the so-called Near Ultra-Violet Silicon Photomultipliers (NUV SiPMs). The tests on photosensors produced by Fondazione Bruno Kessler (FBK) are revealing promising performance: low operating voltage, capability to detect very low intensity light down to a single photon and high Photo Detection Efficiency (PDE) in the range 390-410 nm. In particular the developed device is a High Density NUV-SiPM (NUV-HD SiPM) based on a micro-cell of 30 μm×30 μm and 6 mm×6 mm area. Tests on this detector in single-cell configuration and in a matrix arrangement have been done. At the same time front-end electronics based on the waveform sampling technique optimized for the new NUV-HD SIPMs is under study and development.

  3. Time resolution of the plastic scintillator strips with matrix photomultiplier readout for J-PET tomograph

    Science.gov (United States)

    Moskal, P.; Rundel, O.; Alfs, D.; Bednarski, T.; Białas, P.; Czerwiński, E.; Gajos, A.; Giergiel, K.; Gorgol, M.; Jasińska, B.; Kamińska, D.; Kapłon, Ł.; Korcyl, G.; Kowalski, P.; Kozik, T.; Krzemień, W.; Kubicz, E.; Niedźwiecki, Sz; Pałka, M.; Raczyński, L.; Rudy, Z.; Sharma, N. G.; Słomski, A.; Silarski, M.; Strzelecki, A.; Wieczorek, A.; Wiślicki, W.; Witkowski, P.; Zieliński, M.; Zoń, N.

    2016-03-01

    Recent tests of a single module of the Jagiellonian Positron Emission Tomography system (J-PET) consisting of 30 cm long plastic scintillator strips have proven its applicability for the detection of annihilation quanta (0.511 MeV) with a coincidence resolving time (CRT) of 0.266 ns. The achieved resolution is almost by a factor of two better with respect to the current TOF-PET detectors and it can still be improved since, as it is shown in this article, the intrinsic limit of time resolution for the determination of time of the interaction of 0.511 MeV gamma quanta in plastic scintillators is much lower. As the major point of the article, a method allowing to record timestamps of several photons, at two ends of the scintillator strip, by means of matrix of silicon photomultipliers (SiPM) is introduced. As a result of simulations, conducted with the number of SiPM varying from 4 to 42, it is shown that the improvement of timing resolution saturates with the growing number of photomultipliers, and that the 2× 5 configuration at two ends allowing to read twenty timestamps, constitutes an optimal solution. The conducted simulations accounted for the emission time distribution, photon transport and absorption inside the scintillator, as well as quantum efficiency and transit time spread of photosensors, and were checked based on the experimental results. Application of the 2× 5 matrix of SiPM allows for achieving the coincidence resolving time in positron emission tomography of ≈ 0.170 ns for 15 cm axial field-of-view (AFOV) and ≈ 0.365 ns for 100 cm AFOV. The results open perspectives for construction of a cost-effective TOF-PET scanner with significantly better TOF resolution and larger AFOV with respect to the current TOF-PET modalities.

  4. Molybdenum Tube Characterization report

    Energy Technology Data Exchange (ETDEWEB)

    Beaux II, Miles Frank [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Usov, Igor Olegovich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-07

    Chemical vapor deposition (CVD) techniques have been utilized to produce free-standing molybdenum tubes with the end goal of nuclear fuel clad applications. In order to produce tubes with properties desirable for this application, deposition rates were lowered requiring long deposition durations on the order of 50 hours. Standard CVD methods as well as fluidized-bed CVD (FBCVD) methods were applied towards these objectives. Characterization of the tubes produced in this manner revealed material suitable for fuel clad applications, but lacking necessary uniformity across the length of the tubes. The production of freestanding Mo tubes that possess the desired properties across their entire length represents an engineering challenge that can be overcome in a next iteration of the deposition system.

  5. Categorising YouTube

    DEFF Research Database (Denmark)

    Simonsen, Thomas Mosebo

    2011-01-01

    This article provides a genre analytical approach to creating a typology of the User Generated Content (UGC) of YouTube. The article investigates the construction of navigation processes on the YouTube website. It suggests a pragmatic genre approach that is expanded through a focus on YouTube’s...... technological affordances. Through an analysis of the different pragmatic contexts of YouTube, it is argued that a taxonomic understanding of YouTube must be analysed in regards to the vacillation of a user-driven bottom-up folksonomy and a hierarchical browsing system that emphasises a culture of competition...... and which favours the already popular content of YouTube. With this taxonomic approach, the UGC videos are registered and analysed in terms of empirically based observations. The article identifies various UGC categories and their principal characteristics. Furthermore, general tendencies of the UGC within...

  6. Wavy tube heat pumping

    Energy Technology Data Exchange (ETDEWEB)

    Haldeman, C. W.

    1985-12-03

    A PVC conduit about 4'' in diameter and a little more than 40 feet long is adapted for being seated in a hole in the earth and surrounds a coaxial copper tube along its length that carries Freon between a heat pump and a distributor at the bottom. A number of wavy conducting tubes located between the central conducting tube and the wall of the conduit interconnect the distributor with a Freon distributor at the top arranged for connection to the heat pump. The wavy conducting tubing is made by passing straight soft copper tubing between a pair of like opposed meshing gears each having four convex points in space quadrature separated by four convex recesses with the radius of curvature of each point slightly less than that of each concave recess.

  7. What Are Neural Tube Defects?

    Science.gov (United States)

    ... NICHD Research Information Clinical Trials Resources and Publications Neural Tube Defects (NTDs): Condition Information Skip sharing on social media links Share this: Page Content What are neural tube defects? Neural (pronounced NOOR-uhl ) tube defects are ...

  8. First TDCR measurements at low energies using a miniature x-ray tube.

    Science.gov (United States)

    Halter, E; Thiam, C; Bobin, C; Bouchard, J; Chambellan, D; Chauvenet, B; Hamel, M; Rocha, L; Trocmé, M; Woo, R

    2014-11-01

    Developed for radionuclide standardization using liquid scintillation, the Triple to Double Coincidence Ratio (TDCR) method is applied using coincidence counting obtained with a specific three-photomultiplier system. For activity determination, a statistical model of light emission is classically used to establish a relation between the detection efficiency and the experimental TDCR value. At LNE-LNHB, a stochastic approach of the TDCR modeling was developed using the Monte Carlo code Geant4. The interest of this TDCR-Geant4 model is the possibility to simulate the propagation of optical photons from their creation in the scintillation vial to the production of photoelectrons in photomultipliers. As an alternative to the use of radionuclide sources, first TDCR measurements are presented using a miniature x-ray tube closely coupled to the scintillation vial. The objective of this new set-up was to enable low-energy depositions (lower than 20 keV) in liquid scintillator in order to study the influence of both time and geometrical dependence between PMTs already observed with radioactive sources. As for the statistical TDCR model, the non-linearity of light emission is implemented in the TDCR-Geant4 model using the Birks formula which depends on the kB factor and the scintillation yield. Measurements performed with the x-ray tube are extended to the assessment of these parameters and they are tested afterwards in the TDCR-Geant4 model for activity measurements of (3)H. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Isolated Fallopian Tube Torsion

    Directory of Open Access Journals (Sweden)

    S. Kardakis

    2013-01-01

    Full Text Available Isolated torsion of the Fallopian tube is a rare gynecological cause of acute lower abdominal pain, and diagnosis is difficult. There are no pathognomonic symptoms; clinical, imaging, or laboratory findings. A preoperative ultrasound showing tubular adnexal masses of heterogeneous echogenicity with cystic component is often present. Diagnosis can rarely be made before operation, and laparoscopy is necessary to establish the diagnosis. Unfortunately, surgery often is performed too late for tube conservation. Isolated Fallopian tube torsion should be suspected in case of acute pelvic pain, and prompt intervention is necessary.

  10. Free-Living Tube Worm Endosymbionts Found at Deep-Sea Vents▿ †

    Science.gov (United States)

    Harmer, Tara L.; Rotjan, Randi D.; Nussbaumer, Andrea D.; Bright, Monika; Ng, Andrew W.; DeChaine, Eric G.; Cavanaugh, Colleen M.

    2008-01-01

    Recent evidence suggests that deep-sea vestimentiferan tube worms acquire their endosymbiotic bacteria from the environment each generation; thus, free-living symbionts should exist. Here, free-living tube worm symbiont phylotypes were detected in vent seawater and in biofilms at multiple deep-sea vent habitats by PCR amplification, DNA sequence analysis, and fluorescence in situ hybridization. These findings support environmental transmission as a means of symbiont acquisition for deep-sea tube worms. PMID:18408062

  11. Tube-Forming Assays.

    Science.gov (United States)

    Brown, Ryan M; Meah, Christopher J; Heath, Victoria L; Styles, Iain B; Bicknell, Roy

    2016-01-01

    Angiogenesis involves the generation of new blood vessels from the existing vasculature and is dependent on many growth factors and signaling events. In vivo angiogenesis is dynamic and complex, meaning assays are commonly utilized to explore specific targets for research into this area. Tube-forming assays offer an excellent overview of the molecular processes in angiogenesis. The Matrigel tube forming assay is a simple-to-implement but powerful tool for identifying biomolecules involved in angiogenesis. A detailed experimental protocol on the implementation of the assay is described in conjunction with an in-depth review of methods that can be applied to the analysis of the tube formation. In addition, an ImageJ plug-in is presented which allows automatic quantification of tube images reducing analysis times while removing user bias and subjectivity.

  12. Chest tube insertion - slideshow

    Science.gov (United States)

    ... presentations/100008.htm Chest tube insertion - series—Normal anatomy To use the sharing features ... pleural space is the space between the inner and outer lining of the lung. It is normally very thin, and lined only ...

  13. Snorkeling and Jones tubes

    OpenAIRE

    Lam, Lewis Y. W.; Weatherhead, Robert G.

    2015-01-01

    We report a case of tympanic membrane rupture during snorkeling in a 17-year-old young man who had previously undergone bilateral Jones tubes placed for epiphora. To our knowledge, this phenomenon has not been previously reported.

  14. Snorkeling and Jones tubes.

    Science.gov (United States)

    Lam, Lewis Y W; Weatherhead, Robert G

    2015-01-01

    We report a case of tympanic membrane rupture during snorkeling in a 17-year-old young man who had previously undergone bilateral Jones tubes placed for epiphora. To our knowledge, this phenomenon has not been previously reported.

  15. Nasogastric feeding tube

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000182.htm Nasogastric feeding tube To use the sharing features on this ... the nose. It can be used for all feedings or for giving a person extra calories. It ...

  16. Ear tube insertion - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100045.htm Ear tube insertion - series—Normal anatomy To use the ... 4 Overview The eardrum (tympanic membrane) separates the ear canal from the middle ear. Review Date 8/ ...

  17. Kinking of medical tubes.

    Science.gov (United States)

    Ingles, David

    2004-05-01

    The phenomenon of kinking in medical tubing remains a problem for some applications, particularly critical ones such as transporting gasses or fluids. Design features are described to prevent its occurrence.

  18. Using a nasogastric tube.

    Science.gov (United States)

    Candy, C

    1986-09-01

    This discussion of the use of a nasogastric tube covers the equipment needed, the method, rehydration and feeding, prolonged nasogastric feeding, and stopping nasogastric feeding. A nasogastric tube is useful when children are unable to drink safely and in sufficient amounts for any of the following reasons: severe dehydration; if intravenous (IV) therapy is unavailable; low birth weight infants; or the child is drowsy or vomiting. Severely malnourished children may be fed initially in this way if they are too weak or anorexic to eat or drink normally. The following equipment is needed: nasogastric tube; lubricating fluid; a syringe; blue litmus paper, if available; adhesive tape; stethoscope if available; and fluid to be given. Explain to the child's parents and the child, if old enough to understand, what will be done; lie infants flat; measure the approximate length from the child's nostril to the ear lobe and then to the top of the abdomen with the tube and mark the position; clean the nostrils to remove the mucus, and lubricate the tip of the tube and gently insert into the nostril; give the child a drink of water if he or she is conscious; continue to pass the tube down until the position marked reaches the nostril; use the syringe to suck up some fluid and test with blue litmus paper to check that the tube is in the stomach; and inject 5-10 ml of fluid (saline or oral rehydration solution, not milk formula) by syringe if satisfied the tube is in the correct position. Where possible, give a continuous drip of fluid. If this is not possible, give frequent small amounts using the syringe as a funnel. If feeding continues for more than 24 hours, clean the nostrils daily with warm water and change the tube to the other nostril every few days. Also keep the mouth very clean with a dilute solution of 8% sodium bicarbonate, if available, or citrus fruit juice. To remove the tube, remove the adhesive tape, take the tube out gently and smoothly, and offer the child a

  19. Magnesium tube hydroforming

    Energy Technology Data Exchange (ETDEWEB)

    Liewald, M.; Pop, R. [Institute for Metal Forming Technology (IFU), Stuttgart (Germany)

    2008-04-15

    Magnesium alloys reveal a good strength-to-weight ratio in the family of lightweight metals and gains potential to provide up to 30% mass savings compared to aluminium and up to 75 % compared to steel. The use of sheet magnesium alloys for auto body applications is however limited due to the relatively low formability at room temperature. Within the scope of this paper, extruded magnesium tubes, which are suitable for hydroforming applications, have been investigated. Results obtained at room temperature using magnesium AZ31 tubes show that circumferential strains are limited to a maximal value of 4%. In order to examine the influence of the forming temperature on tube formability, investigations have been carried out with a new die set for hot internal high pressure (IHP) forming at temperatures up to 400 C. Earlier investigations with magnesium AZ31 tubes have shown that fractures occur along the welding line at tubes extruded over a spider die, whereby a non-uniform expansion at bursting with an elongation value of 24% can be observed. A maximum circumferential strain of approx. 60% could be attained when seamless, mechanically pre-expanded and annealed tubes of the same alloy have been used. The effect of annealing time on materials forming properties shows a fine grained structure for sufficient annealing times as well as deterioration with a large increase at same time. Hence, seamless ZM21 tubes have been used in the current investigations. With these tubes, an increased tensile fracture strain of 116% at 350 C is observed as against 19% at 20 C, obtained by tensile testing of milled specimens from the extruded tubes. This behaviour is also seen under the condition of tool contact during the IHP forming process. To determine the maximum circumferential strain at different forming temperatures and strain rates, the tubes are initially bulged in a die with square cross-section under plane stress conditions. Thereafter, the tubes are calibrated by using an

  20. Power vacuum tubes handbook

    CERN Document Server

    Whitaker, Jerry

    2012-01-01

    Providing examples of applications, Power Vacuum Tubes Handbook, Third Edition examines the underlying technology of each type of power vacuum tube device in common use today. The author presents basic principles, reports on new development efforts, and discusses implementation and maintenance considerations. Supporting mathematical equations and extensive technical illustrations and schematic diagrams help readers understand the material. Translate Principles into Specific Applications This one-stop reference is a hands-on guide for engineering personnel involved in the design, specification,

  1. Development of gamma-photon/Cerenkov-light hybrid system for simultaneous imaging of I-131 radionuclide

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Seiichi; Suzuki, Mayumi; Kato, Katsuhiko [Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine (Japan); Watabe, Tadashi; Ikeda, Hayato; Kanai, Yasukazu [Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine (Japan); Ogata, Yoshimune [Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine (Japan); Hatazawa, Jun [Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine (Japan)

    2016-09-11

    Although iodine 131 (I-131) is used for radionuclide therapy, high resolution images are difficult to obtain with conventional gamma cameras because of the high energy of I-131 gamma photons (364 keV). Cerenkov-light imaging is a possible method for beta emitting radionuclides, and I-131 (606 MeV maximum beta energy) is a candidate to obtain high resolution images. We developed a high energy gamma camera system for I-131 radionuclide and combined it with a Cerenkov-light imaging system to form a gamma-photon/Cerenkov-light hybrid imaging system to compare the simultaneously measured images of these two modalities. The high energy gamma imaging detector used 0.85-mm×0.85-mm×10-mm thick GAGG scintillator pixels arranged in a 44×44 matrix with a 0.1-mm thick reflector and optical coupled to a Hamamatsu 2 in. square position sensitive photomultiplier tube (PSPMT: H12700 MOD). The gamma imaging detector was encased in a 2 cm thick tungsten shield, and a pinhole collimator was mounted on its top to form a gamma camera system. The Cerenkov-light imaging system was made of a high sensitivity cooled CCD camera. The Cerenkov-light imaging system was combined with the gamma camera using optical mirrors to image the same area of the subject. With this configuration, we simultaneously imaged the gamma photons and the Cerenkov-light from I-131 in the subjects. The spatial resolution and sensitivity of the gamma camera system for I-131 were respectively ~3 mm FWHM and ~10 cps/MBq for the high sensitivity collimator at 10 cm from the collimator surface. The spatial resolution of the Cerenkov-light imaging system was 0.64 mm FWHM at 10 cm from the system surface. Thyroid phantom and rat images were successfully obtained with the developed gamma-photon/Cerenkov-light hybrid imaging system, allowing direct comparison of these two modalities. Our developed gamma-photon/Cerenkov-light hybrid imaging system will be useful to evaluate the advantages and disadvantages of these two

  2. Development of gamma-photon/Cerenkov-light hybrid system for simultaneous imaging of I-131 radionuclide

    Science.gov (United States)

    Yamamoto, Seiichi; Suzuki, Mayumi; Kato, Katsuhiko; Watabe, Tadashi; Ikeda, Hayato; Kanai, Yasukazu; Ogata, Yoshimune; Hatazawa, Jun

    2016-09-01

    Although iodine 131 (I-131) is used for radionuclide therapy, high resolution images are difficult to obtain with conventional gamma cameras because of the high energy of I-131 gamma photons (364 keV). Cerenkov-light imaging is a possible method for beta emitting radionuclides, and I-131 (606 MeV maximum beta energy) is a candidate to obtain high resolution images. We developed a high energy gamma camera system for I-131 radionuclide and combined it with a Cerenkov-light imaging system to form a gamma-photon/Cerenkov-light hybrid imaging system to compare the simultaneously measured images of these two modalities. The high energy gamma imaging detector used 0.85-mm×0.85-mm×10-mm thick GAGG scintillator pixels arranged in a 44×44 matrix with a 0.1-mm thick reflector and optical coupled to a Hamamatsu 2 in. square position sensitive photomultiplier tube (PSPMT: H12700 MOD). The gamma imaging detector was encased in a 2 cm thick tungsten shield, and a pinhole collimator was mounted on its top to form a gamma camera system. The Cerenkov-light imaging system was made of a high sensitivity cooled CCD camera. The Cerenkov-light imaging system was combined with the gamma camera using optical mirrors to image the same area of the subject. With this configuration, we simultaneously imaged the gamma photons and the Cerenkov-light from I-131 in the subjects. The spatial resolution and sensitivity of the gamma camera system for I-131 were respectively ~3 mm FWHM and ~10 cps/MBq for the high sensitivity collimator at 10 cm from the collimator surface. The spatial resolution of the Cerenkov-light imaging system was 0.64 mm FWHM at 10 cm from the system surface. Thyroid phantom and rat images were successfully obtained with the developed gamma-photon/Cerenkov-light hybrid imaging system, allowing direct comparison of these two modalities. Our developed gamma-photon/Cerenkov-light hybrid imaging system will be useful to evaluate the advantages and disadvantages of these two

  3. Aeronautical tubes and pipes

    Science.gov (United States)

    Beauclair, N.

    1984-12-01

    The main and subcomponent French suppliers of aircraft tubes and pipes are discussed, and the state of the industry is analyzed. Quality control is essential for tubes with regard to their i.d. and metallurgical compositions. French regulations do not allow welded seam tubes in hydraulic circuits unless no other form is available, and then rustproofed steel must be installed. The actual low level of orders for any run of tubes dictates that the product is only one of several among the manufacturers' line. Automation, both in NDT and quality control, assures that the tubes meet specifications. A total of 10 French companies participate in the industry, serving both civil and military needs, with some companies specializing only in titanium, steel, or aluminum materials. Concerns wishing to enter the market must upgrade their equipment to meet the higher aeronautical specifications and be prepared to furnish tubes and pipes that serve both functional and structural purposes simultaneously. Additionally, pipe-bending machines must also perform to tight specifications. Pipes can range from 0.2 mm exterior diameter to 40 mm, with wall thicknesses from 0.02 mm to 3 mm. A chart containing a list of manufacturers and their respective specifications and characteristics is presented, and a downtrend in production with reduction of personnel is noted.

  4. A gas laser tube

    Energy Technology Data Exchange (ETDEWEB)

    Tetsuo, F.; Tokhikhide, N.

    1984-04-19

    A gas laser tube is described in which contamination of the laser gas mixture by the coolant is avoided, resulting in a longer service life of the mirrors. The holder contains two tubes, one inside the other. The laser gas mixture flows through the internal tube. An electrode is fastened to the holder. The coolant is pumped through the slot between the two tubes, for which a hole is cut into the holder. The external tube has a ring which serves to seal the cavity containing the coolant from the atmosphere. The internal tube has two rings, one to seal the laser gas mixture and the other to seal the coolant. A slot is located between these two rings, which leads to the atmosphere (the atmosphere layer). With this configuration, the degradation of the sealing properties of the internal ring caused by interaction with the atmospheric layer is not reflected in the purity of the laser gas mixture. Moreover, pollution of the mirrors caused by the penetration of the coolant into the cavity is eliminated.

  5. Dynamic tube/support interaction in heat exchanger tubes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, S.S.

    1991-01-01

    The supports for heat exchanger tubes are usually plates with drilled holes; other types of supports also have been used. To facilitate manufacture and to allow for thermal expansion of the tubes, small clearances are used between tubes and tube supports. The dynamics of tube/support interaction in heat exchangers is fairly complicated. Understanding tube dynamics and its effects is important for heat exchangers. This paper summarizes the current state of the art on this subject and to identify future research needs. Specifically, the following topics are discussed: dynamics of loosely supported tubes, tube/support gap dynamics, tube response in flow, tube damage and wear, design considerations, and future research needs. 55 refs., 1 fig.

  6. Endurance of Damping Properties of Foam-Filled Tubes.

    Science.gov (United States)

    Strano, Matteo; Marra, Alessandro; Mussi, Valerio; Goletti, Massimo; Bocher, Philippe

    2015-07-07

    The favorable energy-absorption properties of metal foams have been frequently proposed for damping or anti-crash applications. The aim of this paper is to investigate the endurance of these properties for composite structures, made by a metal or a hybrid metal-polymeric foam used as the core filling of a tubular metal case. The results of experimental tests are shown, run with two types of structures: 1) square steel tubes filled with aluminum or with hybrid aluminum-polymer foams; 2) round titanium tubes filled with aluminum foams. The paper shows that the damping properties of a foam-filled tube change (improve) with the number of cycles, while all other dynamic properties are nearly constant. This result is very important for several potential applications where damping is crucial, e.g., for machine tools.

  7. Endurance of Damping Properties of Foam-Filled Tubes

    Directory of Open Access Journals (Sweden)

    Matteo Strano

    2015-07-01

    Full Text Available The favorable energy-absorption properties of metal foams have been frequently proposed for damping or anti-crash applications. The aim of this paper is to investigate the endurance of these properties for composite structures, made by a metal or a hybrid metal-polymeric foam used as the core filling of a tubular metal case. The results of experimental tests are shown, run with two types of structures: 1 square steel tubes filled with aluminum or with hybrid aluminum-polymer foams; 2 round titanium tubes filled with aluminum foams. The paper shows that the damping properties of a foam-filled tube change (improve with the number of cycles, while all other dynamic properties are nearly constant. This result is very important for several potential applications where damping is crucial, e.g., for machine tools.

  8. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... search for current job openings visit HHS USAJobs Home > NEI YouTube Videos > NEI YouTube Videos: Amblyopia NEI YouTube Videos YouTube Videos Home Age-Related Macular Degeneration Amblyopia Animations Blindness Cataract ...

  9. Spatial distributions of photons in plastic scintillator detected by multi-anode photomultiplier for heavy-ion position determination

    Energy Technology Data Exchange (ETDEWEB)

    Omika, S. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Yamaguchi, T., E-mail: yamaguti@phy.saitama-u.ac.jp [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Fukuda, M. [Department of Physics, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Kitagawa, A. [National Institute of Radiological Sciences, Chiba 263-8555 (Japan); Matsunaga, S. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Nagae, D. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Nishimura, D. [Department of Physics, Tokyo University of Science, Noda 278-8510 (Japan); Nishimura, T. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Ozawa, A. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Sato, S. [National Institute of Radiological Sciences, Chiba 263-8555 (Japan); Sawahata, K. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Suzuki, T.; Takeuchi, Y. [Department of Physics, Saitama University, Saitama 338-8570 (Japan)

    2015-10-11

    The spatial distributions of scintillation photons in a plastic scintillation detector were measured using a multi-anode photomultiplier H7546A coupled with 1-mm-diameter optical fibers. A row of several tens of fibers connected to the scintillator generates one-dimensional spatial distributions of photons induced by the swift passage of heavy ions. The pulse heights from each channel change depending on the beam position. This can be utilized to determine the positions of the heavy ions. To test the performance of the proposed detection method, an experiment using a {sup 84}Kr beam with intermediate energies ranging from 40 to 85 MeV/nucleon was performed at the heavy-ion medical accelerator in Chiba (HIMAC). The photon spatial distributions were successfully observed. By optimizing the photomultiplier bias voltage and threshold in the pulse height analyses, a detection efficiency of 98% and a position resolution of 1.1 mm in σ were achieved simultaneously.

  10. Performance of Silicon Photomultipliers for the Dual-Mirror Medium-Sized Telescopes of the Cherenkov Telescope Array

    CERN Document Server

    Biteau, Jonathan; Dang, Dennis; Doyle, Kevin; Johnson, Caitlin A.; Williams, David A.

    2015-01-01

    Gamma-ray observations in the very-high-energy domain (E > 30 GeV) can exploit the imaging of few-nanosecond Cherenkov flashes from atmospheric particle showers. Photomultipliers have been used as the primary photosensors to detect gamma-ray induced Cherenkov light for the past 25 years, but they are increasingly challenged by the swift progress of silicon photomultipliers (SiPMs). We are working to identify the optimal photosensors for medium-sized Schwarzschild-Couder telescopes (SCT), which are proposed to contribute a significant fraction of the sensitivity of the Cherenkov Telescope Array in its core energy range. We present the capabilities of the latest SiPMs from the Hamamatsu, SensL, and Excelitas companies that we have characterized in our laboratory, and compare them to the SiPMs equipping the prototype SCT camera that is under construction.

  11. Using ASD8 as readout of multianode photomultipliers for single photoelectron discrimination in the HERA-B RICH detector

    Science.gov (United States)

    Ariño, I.; Chmeissani, M.; Conde, P.; Garrido, L.; Gascon, D.; Miquel, R.; Peralta, D.; Sieiro, J.

    2001-01-01

    ASD8 is the analog front end chosen to read out the photodetectors of the HERA-B RICH. A test of 1791 boards was performed to study which were the best operating conditions, to make a quality assessment and to optimize the distribution of the boards on the RICH focal plane. Nevertheless, some drawbacks are apparent when a board designed for tracker detectors is employed to convert a photomultiplier signal.

  12. Particle physics methodologies applied to time-of-flight positron emission tomography with silicon-photomultipliers and inorganic scintillators

    OpenAIRE

    Leming, Edward J

    2015-01-01

    Positron emission tomography, or PET, is a medical imaging technique which has been used in clinical environments for over two decades. With the advent of fast timing detectors and scintillating crystals, it is possible to envisage improvements to the technique\\ud with the inclusion of time-of-flight capabilities. In this context, silicon photomultipliers coupled to fast inorganic LYSO crystals are investigated as a possible technology choice. As part of the ENVISION collaboration a range of ...

  13. A gain regulation system for a large set of photomultipliers using light-emitting diodes and optical filters

    CERN Document Server

    De Palma, M; Sacchetti, A; Spirelli, P; Waldner, F

    1979-01-01

    Describes the solution adopted for the on-line gain regulation with a PDP 11/60 of the 480 photomultipliers of the calorimeter of the experiment NA5 (at CERN) by means of light emitting diodes (LEDs) and polymer optical fibers. The regulation of the light yield of the LEDs is obtained comparing it to the light pulse of a NaI scintillator doped with /sup 241/Am. (6 refs).

  14. A double photomultiplier Compton camera and its readout system for mice imaging

    Science.gov (United States)

    Fontana, Cristiano Lino; Atroshchenko, Kostiantyn; Baldazzi, Giuseppe; Bello, Michele; Uzunov, Nikolay; Di Domenico, Giovanni Di

    2013-04-01

    We have designed a Compton Camera (CC) to image the bio-distribution of gamma-emitting radiopharmaceuticals in mice. A CC employs the "electronic collimation", i.e. a technique that traces the gamma-rays instead of selecting them with physical lead or tungsten collimators. To perform such a task, a CC measures the parameters of the Compton interaction that occurs in the device itself. At least two detectors are required: one (tracker), where the primary gamma undergoes a Compton interaction and a second one (calorimeter), in which the scattered gamma is completely absorbed. Eventually the polar angle and hence a "cone" of possible incident directions are obtained (event with "incomplete geometry"). Different solutions for the two detectors are proposed in the literature: our design foresees two similar Position Sensitive Photomultipliers (PMT, Hamamatsu H8500). Each PMT has 64 output channels that are reduced to 4 using a charge multiplexed readout system, i.e. a Series Charge Multiplexing net of resistors. Triggering of the system is provided by the coincidence of fast signals extracted at the last dynode of the PMTs. Assets are the low cost and the simplicity of design and operation, having just one type of device; among drawbacks there is a lower resolution with respect to more sophisticated trackers and full 64 channels Readout. This paper does compare our design of our two-Hamamatsu CC to other solutions and shows how the spatial and energy accuracy is suitable for the inspection of radioactivity in mice.

  15. Digital silicon photomultiplier readout of a new fast and bright scintillation crystal (Ce:GFAG)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong-Seok [Department of Bio-convergence Engineering, Korea University, Seoul (Korea, Republic of); Leem, Hyun-Tae [Molecular Imaging Research & Education (MiRe) Laboratory, Department of Electronic Engineering, Sogang University, Seoul (Korea, Republic of); Yamamoto, Seiichi [Department of Medical Technology, Nagoya University Graduate School of Medicine, Nagoya (Japan); Choi, Yong, E-mail: ychoi@sogang.ac.kr [Molecular Imaging Research & Education (MiRe) Laboratory, Department of Electronic Engineering, Sogang University, Seoul (Korea, Republic of); Kamada, Kei [New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai (Japan); C& A corporation, Sendai (Japan); Yoshikawa, Akira [New Industry Creation Hatchery Center (NICHe), Tohoku University, Sendai (Japan); C& A corporation, Sendai (Japan); Institute for Material Research, Tohoku University, Sendai (Japan); Park, Sang-Geon [Department of Electrical & Electronics, Silla University, Pusan (Korea, Republic of); Yeom, Jung-Yeol, E-mail: jungyeol@korea.ac.kr [Department of Bio-convergence Engineering, Korea University, Seoul (Korea, Republic of); School of Biomedical Engineering, Korea University, Seoul (Korea, Republic of)

    2016-10-01

    A new Gadolinium Fine Aluminum Gallate (Ce:GFAG) scintillation crystal with both high energy resolution and fast timing properties has successfully been grown. Compared to Gd{sub 3}Al{sub 2}Ga{sub 3}O{sub 12} (Ce:GAGG), this new inorganic scintillation crystal has a high luminosity similar to and a faster decay time. In this paper, we report on the timing and energy performance results of the new GFAG scintillation crystal read out with digital silicon photomultipliers (dSiPM) for positron emission tomography (PET) application. The best coincidence resolving time (FWHM) of polished 3×3×5 mm{sup 3} crystals was 223±6 ps for GFAG crystals compared to 396±28 ps for GAGG crystals and 131±3 ps for LYSO crystals respectively. An energy resolution (511 keV peak of Na-22) of 10.9±0.2% was attained with GFAG coupled to dSiPM after correcting for saturation effect, compared to 9.5±0.3% for Ce:GAGG crystals and 11.9±0.4% for LYSO crystals respectively. It is expected that this new scintillator may be competitive in terms of overall properties such as energy resolution, timing resolution and growing (raw material) cost, compared to existing scintillators for positron emission tomography (PET).

  16. Real-time fluorescence lifetime actuation for cell sorting using a CMOS SPAD silicon photomultiplier.

    Science.gov (United States)

    Rocca, Francescopaolo Mattioli Della; Nedbal, Jakub; Tyndall, David; Krstajić, Nikola; Li, David Day-Uei; Ameer-Beg, Simon M; Henderson, Robert K

    2016-02-15

    Time-correlated single photon counting (TCSPC) is a fundamental fluorescence lifetime measurement technique offering high signal to noise ratio (SNR). However, its requirement for complex software algorithms for histogram processing restricts throughput in flow cytometers and prevents on-the-fly sorting of cells. We present a single-point digital silicon photomultiplier (SiPM) detector accomplishing real-time fluorescence lifetime-activated actuation targeting cell sorting applications in flow cytometry. The sensor also achieves burst-integrated fluorescence lifetime (BIFL) detection by TCSPC. The SiPM is a single-chip complementary metal-oxide-semiconductor (CMOS) sensor employing a 32×32 single-photon avalanche diode (SPAD) array and eight pairs of time-interleaved time to digital converters (TI-TDCs) with a 50 ps minimum timing resolution. The sensor's pile-up resistant embedded center of mass method (CMM) processor accomplishes low-latency measurement and thresholding of fluorescence lifetime. A digital control signal is generated with a 16.6 μs latency for cell sorter actuation allowing a maximum cell throughput of 60,000 cells per second and an error rate of 0.6%.

  17. An innovative silicon photomultiplier digitizing camera for gamma-ray astronomy

    CERN Document Server

    Heller, Matthieu; Porcelli, Alessio; Pujadas, Isaac Troyano; Zietara, Krzysztof; Della Volpe, Domenico; Montaruli, Teresa; Cadoux, Franck; Favre, Yannick; Sanchez, Juan Antonio Aguilar; Christov, Asen; Prandini, Elisa; Rajda, Pawel; Rameez, Mohamed; Blinik, Woijciech; Blocki, Jacek; Bogacz, Leszek; Borkowski, Jurek; Bulik, Tomasz; Frankowski, Adam; Grudzinska, Mira; Idzkowski, Bartosz; Jamrozy, Mateusz; Janiak, Mateusz; Kasperek, Jerzy; Lalik, Krzysztof; Lyard, Etienne; Mach, Emil; Mandat, Dusan; Marszalek, Adrian; Miranda, Luis David Medina; Michalowski, Jerzy; Neronov, Andrii; Niemiec, Jacek; Ostrowski, Michal; Pasko, Pawel; Pech, Miroslav; Schovanek, Petr; Seweryn, Karol; Sliusar, Vitalii; Skowron, Krzysztof; Stawarz, Lukasz; Stodulska, Magdalena; Stodulski, Marek; Walter, Roland; Wiecek, Marek; Zagdanski, Aleksander

    2016-01-01

    The single-mirror small-size telescope (SST-1M) is one of the three proposed designs for the small-size telescopes (SSTs) of the Cherenkov Telescope Array (CTA) project. The SST-1M will be equipped with a 4 m-diameter segmented mirror dish and an innovative fully digital camera based on silicon photo-multipliers (SiPMs). Since the SST sub-array will consist of up to 70 telescopes, the challenge is not only to build a telescope with excellent performance, but also to design it so that its components can be commissioned, assembled and tested by industry. In this paper we review the basic steps that led to the design concepts for the SST-1M camera and the ongoing realization of the first prototype, with focus on the innovative solutions adopted for the photodetector plane and the readout and trigger parts of the camera. In addition, we report on results of laboratory measurements on real scale elements that validate the camera design and show that it is capable of matching the CTA requirements of operating up to...

  18. Review of solid state photomultiplier developments by CPTA and photonique SA

    Energy Technology Data Exchange (ETDEWEB)

    McNally, David [Photonique SA, Ch. du Grand-Puits 38, 1217 Meyrin (Switzerland)], E-mail: dmcnally@photonique.ch; Golovin, Victor [CPTA, 1-ya Vladimirskaya 22, kor 2, 111141 Moscow (Russian Federation)

    2009-10-21

    We report on recently developed solid state photomultipliers (SSPMs) based on the Metal Resistive Silicon Geiger-mode Avalanche Photodiode architecture (MRS-APD). SSPMs implementing a n+ p p+ doping structure now reach up to 50% peak photon detection efficiency in the green and red parts of the visible spectrum. They operate at high gain (>3x10{sup 5}) and have exceptionally low temperature coefficient (<1.0%/deg. C). Optical cross-talk between SSPM micro-cells is significantly reduced through the use of optical trenches. Building on this technology, single die photon detectors with 1.0, 4.4 and 9.0 mm{sup 2} sensitive areas have been manufactured. Special surface treatment techniques allow for an increase of UV and blue light sensitivity for these green-red sensitive devices. We also report on SSPMs employing a p+ p n+ doping structure which exhibit high sensitivity for blue and UV light with photon detection efficiency reaching up to 30% at 420 nm.

  19. An innovative silicon photomultiplier digitizing camera for gamma-ray astronomy

    Energy Technology Data Exchange (ETDEWEB)

    Heller, M. [DPNC-Universite de Geneve, Geneva (Switzerland); Schioppa, E. Jr; Porcelli, A.; Pujadas, I.T.; Della Volpe, D.; Montaruli, T.; Cadoux, F.; Favre, Y.; Christov, A.; Rameez, M.; Miranda, L.D.M. [DPNC-Universite de Geneve, Geneva (Switzerland); Zietara, K.; Idzkowski, B.; Jamrozy, M.; Ostrowski, M.; Stawarz, L.; Zagdanski, A. [Jagellonian University, Astronomical Observatory, Krakow (Poland); Aguilar, J.A. [DPNC-Universite de Geneve, Geneva (Switzerland); Universite Libre Bruxelles, Faculte des Sciences, Brussels (Belgium); Prandini, E.; Lyard, E.; Neronov, A.; Walter, R. [Universite de Geneve, Department of Astronomy, Geneva (Switzerland); Rajda, P.; Bilnik, W.; Kasperek, J.; Lalik, K.; Wiecek, M. [AGH University of Science and Technology, Krakow (Poland); Blocki, J.; Mach, E.; Michalowski, J.; Niemiec, J.; Skowron, K.; Stodulski, M. [Instytut Fizyki Jadrowej im. H. Niewodniczanskiego Polskiej Akademii Nauk, Krakow (Poland); Bogacz, L. [Jagiellonian University, Department of Information Technologies, Krakow (Poland); Borkowski, J.; Frankowski, A.; Janiak, M.; Moderski, R. [Polish Academy of Science, Nicolaus Copernicus Astronomical Center, Warsaw (Poland); Bulik, T.; Grudzinska, M. [University of Warsaw, Astronomical Observatory, Warsaw (Poland); Mandat, D.; Pech, M.; Schovanek, P. [Institute of Physics of the Czech Academy of Sciences, Prague (Czech Republic); Marszalek, A.; Stodulska, M. [Instytut Fizyki Jadrowej im. H. Niewodniczanskiego Polskiej Akademii Nauk, Krakow (Poland); Jagellonian University, Astronomical Observatory, Krakow (Poland); Pasko, P.; Seweryn, K. [Centrum Badan Kosmicznych Polskiej Akademii Nauk, Warsaw (Poland); Sliusar, V. [Universite de Geneve, Department of Astronomy, Geneva (Switzerland); Taras Shevchenko National University of Kyiv, Astronomical Observatory, Kyiv (Ukraine)

    2017-01-15

    The single-mirror small-size telescope (SST-1M) is one of the three proposed designs for the small-size telescopes (SSTs) of the Cherenkov Telescope Array (CTA) project. The SST-1M will be equipped with a 4 m-diameter segmented reflector dish and an innovative fully digital camera based on silicon photo-multipliers. Since the SST sub-array will consist of up to 70 telescopes, the challenge is not only to build telescopes with excellent performance, but also to design them so that their components can be commissioned, assembled and tested by industry. In this paper we review the basic steps that led to the design concepts for the SST-1M camera and the ongoing realization of the first prototype, with focus on the innovative solutions adopted for the photodetector plane and the readout and trigger parts of the camera. In addition, we report on results of laboratory measurements on real scale elements that validate the camera design and show that it is capable of matching the CTA requirements of operating up to high moonlight background conditions. (orig.)

  20. A design of a valid signal selecting and position decoding ASIC for PET using silicon photomultipliers

    Science.gov (United States)

    Cho, M.; Lim, K.-t.; Kim, H.; Yeom, J.-y.; Kim, J.; Lee, C.; Choi, H.; Cho, G.

    2017-01-01

    In most cases, a PET system has numerous electrical components and channel circuits and thus it would rather be a bulky product. Also, most existing systems receive analog signals from detectors which make them vulnerable to signal distortions. For these reasons, channel reduction techniques are important. In this work, an ASIC for PET module is being proposed. An ASIC chip for 16 PET detector channels, VSSPDC, has been designed and simulated. The main function of the chip is 16-to-1 channel reduction, i.e., finding the position of only the valid signals, signal timing, and magnitudes in all 16 channels at every recorded event. The ASIC comprises four of 4-channel modules and a 2nd 4-to-1 router. A single channel module comprises a transimpedance amplifier for the silicon photomultipliers, dual comparators with high and low level references, and a logic circuitry. While the high level reference was used to test the validity of the signal, the low level reference was used for the timing. The 1-channel module of the ASIC produced an energy pulse by time-over-threshold method and it also produced a time pulse with a fixed delayed time. Since the ASIC chip outputs only a few digital pulses and does not require an external clock, it has an advantage over noise properties. The cadence simulation showed the good performance of the chip as designed.

  1. Characterization of silicon photomultipliers at National Nano-Fab Center for PET-MR.

    Science.gov (United States)

    Kim, Hyoungtaek; Sul, Woo Suk; Cho, Gyuseong

    2014-10-01

    The silicon photomultipliers (SiPMs) were fabricated for magnetic resonance compatible positron emission tomography (PET) applications using customized CMOS processes at National NanoFab Center. Each micro-cell consists of a shallow n+/p well junction on a p-type epitaxial wafer and passive quenching circuit was applied. The size of the SiPM is 3 × 3 mm(2) and the pitch of each micro-cell is 65 μm. In this work, several thousands of SiPMs were packaged and tested to build a PET ring detector which has a 60 mm axial and 390 mm radial field of view. I-V characteristics of the SiPMs are shown good uniformity and breakdown voltage is around 20 V. The photon detection efficiency was measured via photon counting method and the maximum value was recorded as 16% at 470 nm. The gamma ray spectrum of a Ge-68 isotope showed nearly 10% energy resolution at 511 keV with a 3 × 3 × 20 mm(3) LYSO crystal.

  2. Integrating printed microfluidics with silicon photomultipliers for miniaturised and highly sensitive ATP bioluminescence detection.

    Science.gov (United States)

    Santangelo, M F; Libertino, S; Turner, A P F; Filippini, D; Mak, W C

    2018-01-15

    Bioluminescence has been widely used for important biosensing applications such as the measurement of adenosine triphosphate (ATP), the energy unit in biological systems and an indicator of vital processes. The current technology for detection is mainly based on large equipment such as readers and imaging systems, which require intensive and time-consuming procedures. A miniaturised bioluminescence sensing system, which would allow sensitive and continuous monitoring of ATP, with an integrated and low-cost disposable microfluidic chamber for handling of biological samples, is highly desirable. Here, we report the design, fabrication and testing of 3D printed microfluidics chips coupled with silicon photomultipliers (SiPMs) for high sensitive real-time ATP detection. The 3D microfluidic chip reduces reactant consumption and facilitates solution delivery close to the SiPM to increase the detection efficiency. Our system detects ATP with a limit of detection (LoD) of 8nM and an analytical dynamic range between 15nM and 1µM, showing a stability error of 3%, and a reproducibility error below of 20%. We demonstrate the dynamic monitoring of ATP in a continuous-flow system exhibiting a fast response time, ~4s, and a full recovery to the baseline level within 17s. Moreover, the SiPM-based bioluminescence sensing system shows a similar analytical dynamic range for ATP detection to that of a full-size PerkinElmer laboratory luminescence reader. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Ultra-high cell-density silicon photomultipliers with high detection efficiency

    Science.gov (United States)

    Acerbi, Fabio; Gola, Alberto; Regazzoni, Veronica; Paternoster, Giovanni; Borghi, Giacomo; Piemonte, Claudio; Zorzi, Nicola

    2017-05-01

    Silicon photomultipliers (SiPMs) are arrays of many single-photon avalanche diodes (SPADs), all connected in parallel. Each SPAD is sensitive to single photons and the SiPM gives an output proportional to the number of detected photons. These sensors are becoming more and more popular in different applications, from high-energy physics to spectroscopy, and they have been significantly improved over last years, decreasing the noise, increasing the cell fill-factor (FF) and thus achieving very high photon-detection efficiency (PDE). In FBK (Trento, Italy), we developed new SiPM technologies with high-density (HD) and, more recently, ultra-high-density (UHD) of cells (i.e. density of SPADs). These technologies employ deep-trenches between cells, for electrical and optical isolation. As an extreme case the smallest-cell, SiPM, i.e. with 5μm cell pitch, has about 40000 SPADs per squared millimeter. Such small SPAD dimensions gives a significantly high dynamic range to the SiPM. These small-cells SiPM have a lower correlated noise (including lower afterpulsing probability) and a faster recharge time (in the order of few nanoseconds), and they also preserve a very good detection efficiency (despite the small SPAD dimension).

  4. A robust and semi-automatic procedure for Silicon Photomultipliers characterisation

    Science.gov (United States)

    Arosio, V.; Beretta, M.; Caccia, M.; Santoro, R.

    2017-03-01

    Silicon Photomultipliers are state-of-the-art solid state sensors of light with single photon sensitivity, unprecedented photon number resolving capability and high photon detection efficiency. SiPM are cost effective, compact, magnetic field insensitive and with an extreme flexibility in the design to cope with different applications in fundamental and applied science and industry. As a rapidly evolving technology, new generation of sensors are being continuously proposed by different producers, requiring the development of reliable and efficient SiPM characterisation methods to perform a quick assessment and comparison. The procedure presented here is based on post-processing of digitised SiPM waveforms recording the response of the sensor to an ultra-fast light pulse. For every pulse, the signal is synchronously sampled, digitised and recorded on the timescale of a few microseconds with the objective of extracting from a single set of waveforms a full picture of the sensor characteristics in terms of Gain, Breakdown Voltage, Dark Count Rate , Optical Cross-Talk and After Pulse probability. The need of a unique and consistent data-set guarantees a fast and robust characterisation, stable against environmental condition changes, notably temperature.

  5. Characterization of scintillating plastic fibers and silicon photomultipliers for their usage in a particle telescope

    Energy Technology Data Exchange (ETDEWEB)

    Pruefer, Lea; Losekamm, Martin; Poeschl, Thomas; Greenwald, Daniel; Paul, Stephan [Technische Universitaet Muenchen, 85748 Garching (Germany)

    2016-07-01

    The Multi-purpose Active-target Particle Telescope (MAPT) is a newly developed compact charged-particle detector. It can be used for space applications, such as radiation monitoring on spacecraft or for stratospheric research balloons. Its core consists of scintillating plastic fibers coupled to silicon photomultiplier (SiPMs). The energy reconstruction of the incoming particles is based on an extended Bragg curve spectroscopy technique, requiring a good measurement of the energy deposition. Therefore, non-linearities of the measured light output -such as quenching effects of the scintillating material or saturation of the SiPMs at high light yields- have to be known quantitatively. To investigate these effects, two scaled-down prototypes were built, consisting of 128 and 16 channels. The first one was tested at a stationary proton beam at Paul Scherrer Institute. We determine Birk's coefficient describing the ionization quenching of the scintillator and calculate the characteristic photon detection efficiency of the SiPMs. We explain the results of the first prototype tests and the characterization of the SiPMs.

  6. Gain compensation technique by bias correction in arrays of Silicon Photomultipliers using fully differential fast shaper

    Energy Technology Data Exchange (ETDEWEB)

    Baszczyk, M., E-mail: baszczyk@agh.edu.pl [AGH University of Science and Technology, Department of Electronics, Krakow (Poland); Dorosz, P.; Glab, S.; Kucewicz, W. [AGH University of Science and Technology, Department of Electronics, Krakow (Poland); Mik, L. [AGH University of Science and Technology, Department of Electronics, Krakow (Poland); State Higher Vocational School, Tarnow (Poland); Sapor, M. [AGH University of Science and Technology, Department of Electronics, Krakow (Poland)

    2016-07-11

    Proposed algorithm compensates the gain by changing the bias voltage of Silicon Photomultipliers (SiPM). The signal from SiPM is amplified in fully differential preamplifier then is formed in time by the fully differential fast shaper. The compensation method was tested with four channels common cathode multi-pixel photon counter from Hamamatsu. The measurement system requires only one high voltage power supply. The polarization voltage is adjusted individually in each channel indirectly by tuning the output common mode voltage (VOCM) of fully differential amplifier. The changes of VOCM affect the input voltage through the feedback network. Actual gain of the SiPM is calculated by measuring the mean amplitude of the signal resulting from detection of single photoelectron. The VOCM is adjusted by DAC so as to reach the desired value of gain by each channel individually. The advantage of the algorithm is the possibility to set the bias of each SiPM in the array independently so they all could operate in very similar conditions (have similar gain and dark count rate). The algorithm can compensate the variations of gain of SiPM by using thermally generated pulses. There is no need to use additional current to voltage conversion which could introduce extra noises.

  7. Radiation Hardness tests with neutron flux on different Silicon photomultiplier devices

    Science.gov (United States)

    Cattaneo, P. W.; Cervi, T.; Menegolli, A.; Oddone, M.; Prata, M.; Prata, M. C.; Rossella, M.

    2017-07-01

    Radiation hardness is an important requirement for solid state readout devices operating in high radiation environments common in particle physics experiments. The MEG II experiment, at PSI, Switzerland, investigates the forbidden decay μ+ → e+ γ. Exploiting the most intense muon beam of the world. A significant flux of non-thermal neutrons (kinetic energy Ek>= 0.5 MeV) is present in the experimental hall produced along the beam-line and in the hall itself. We present the effects of neutron fluxes comparable to the MEG II expected doses on several Silicon Photomultiplier (SiPMs). The tested models are: AdvanSiD ASD-NUV3S-P50 (used in MEG II experiment), AdvanSiD ASD-NUV3S-P40, AdvanSiD ASD-RGB3S-P40, Hamamatsu and Excelitas C30742-33-050-X. The neutron source is the thermal Sub-critical Multiplication complex (SM1) moderated with water, located at the University of Pavia (Italy). We report the change of SiPMs most important electric parameters: dark current, dark pulse frequency, gain, direct bias resistance, as a function of the integrated neutron fluency.

  8. Investigation of Very Fast Light Detectors: Silicon Photomultiplier and Micro PMT for a Cosmic Ray Array

    Science.gov (United States)

    Cervantes, Omar; Reyes, Liliana; Hooks, Tyler; Perez, Luis; Ritt, Stefan

    2016-03-01

    To construct a cosmic detector array using 4 scintillation detectors, we investigated 2 recent light sensor technologies from Hamamatsu, as possible readout detectors. First, we investigated several homemade versions of the multipixel photon counter (MPPC) light sensors. These detectors were either biased with internal or external high voltage power supplies. We made extensive measurements to confirm for the coincidence of the MPPC devices. Each sensor is coupled to a wavelength shifting fiber (WSF) that is embedded along a plastic scintillator sheet (30cmx60cmx1/4''). Using energetic cosmic rays, we evaluated several of these homemade detector modules placed above one another in a light proof enclosure. Next, we assembled 2 miniaturized micro photomultiplier (micro PMT), a device recently marketed by Hamamatsu. These sensors showed very fast response times. With 3 WSF embedded in scintillator sheets, we performed coincidence experiments. The detector waveforms were captured using the 5GS/sec domino ring sampler, the DRS4 and our workflow using the CERN PAW package and data analysis results would be presented. Title V Grant.

  9. Balloon Flight Test of a Compton Telescope Based on Scintillators with Silicon Photomultiplier Readouts

    CERN Document Server

    Bloser, P F; Bancroft, C M; Ryan, J M; McConnell, M L

    2016-01-01

    We present the results of the first high-altitude balloon flight test of a concept for an advanced Compton telescope making use of modern scintillator materials with silicon photomultiplier (SiPM) readouts. There is a need in the fields of high-energy astronomy and solar physics for new medium-energy gamma-ray (~0.4 - 10 MeV) detectors capable of making sensitive observations. A fast scintillator- based Compton telescope with SiPM readouts is a promising solution to this instrumentation challenge, since the fast response of the scintillators permits the rejection of background via time-of-flight (ToF) discrimination. The Solar Compton Telescope (SolCompT) prototype was designed to demonstrate stable performance of this technology under balloon-flight conditions. The SolCompT instrument was a simple two-element Compton telescope, consisting of an approximately one-inch cylindrical stilbene crystal for a scattering detector and a one-inch cubic LaBr3:Ce crystal for a calorimeter detector. Both scintillator dete...

  10. A Compact Cosmic Ray Telescope using Silicon Photomultipliers for use in High Schools

    Science.gov (United States)

    Castro, Luis; Elizondo, Leonardo; Shelor, Mark; Cervantes, Omar; Fan, Sewan; Ritt, Stefan

    2016-03-01

    Over the years, the QuarkNet and the LBL Cosmic Ray Project have helped trained thousands of high school students and teachers to explore cosmic ray physics. To get high school students in the Salinas, CA area also excited about cosmic rays, we constructed a cosmic ray telescope as a physics outreach apparatus. Our apparatus includes a pair of plastic scintillators coupled to silicon photomultipliers (SiPM) and a coincidence circuit board. We designed and constructed custom circuit boards for mounting the SiPM detectors, the high voltage power supplies and coincidence AND circuit. The AND logic signals can be used for triggering data acquisition devices including an oscilloscope, a waveform digitizer or an Arduino microcontroller. To properly route the circuit wire traces, the circuit boards were layout in Eagle and fabricated in-house using a circuit board maker from LPKF LASER, model Protomat E33. We used a Raspberry Pi computer to control a fast waveform sampler, the DRS4 to digitize the SiPM signal waveforms. The CERN PAW software package was used to analyze the amplitude and time distributions of SiPM detector signals. At this conference, we present our SiPM experimental setup, circuit board fabrication procedures and the data analysis work flow. AIP Megger's Award, Dept. of Ed. Title V Grant PO31S090007.

  11. Performance study of Philips digital silicon photomultiplier coupled to scintillating crystals

    CERN Document Server

    Liu, Z.; Auffray, E.; Lecoq, P.; Paganoni, M.

    2016-01-01

    Silicon photomultipliers (SiPMs) and scintillators are often arranged in the shape of arrays in Positron Emission Tomography (PET) systems. Digital SiPMs provide signal readout in single photon avalanche diode (SPAD) level. From the photon count rate measurement of each SPAD cell of digital SiPM, we found that the output scintillating photons distribute in an area larger than the scintillator physical coupling area. Taking advantage of the possibility to enable/disable individual cells of the digital SiPM, a group of Lutetium-yttrium oxyorthosilicate (LYSO) crystals with different dimensions coupled to a digital SiPM was used to study the influence of using different SiPM active area on the number of photons detected, energy resolution and coincidence time resolution (CTR). For the same crystal coupled to the digital SiPM, the larger the active area of digital SiPM, the higher the number of photons detected. The larger active area of the digital SiPM also results in a better energy resolution after saturation...

  12. Digital silicon photomultiplier readout of a new fast and bright scintillation crystal (Ce:GFAG)

    Science.gov (United States)

    Lee, Yong-Seok; Leem, Hyun-Tae; Yamamoto, Seiichi; Choi, Yong; Kamada, Kei; Yoshikawa, Akira; Park, Sang-Geon; Yeom, Jung-Yeol

    2016-10-01

    A new Gadolinium Fine Aluminum Gallate (Ce:GFAG) scintillation crystal with both high energy resolution and fast timing properties has successfully been grown. Compared to Gd3Al2Ga3O12 (Ce:GAGG), this new inorganic scintillation crystal has a high luminosity similar to and a faster decay time. In this paper, we report on the timing and energy performance results of the new GFAG scintillation crystal read out with digital silicon photomultipliers (dSiPM) for positron emission tomography (PET) application. The best coincidence resolving time (FWHM) of polished 3×3×5 mm3 crystals was 223±6 ps for GFAG crystals compared to 396±28 ps for GAGG crystals and 131±3 ps for LYSO crystals respectively. An energy resolution (511 keV peak of Na-22) of 10.9±0.2% was attained with GFAG coupled to dSiPM after correcting for saturation effect, compared to 9.5±0.3% for Ce:GAGG crystals and 11.9±0.4% for LYSO crystals respectively. It is expected that this new scintillator may be competitive in terms of overall properties such as energy resolution, timing resolution and growing (raw material) cost, compared to existing scintillators for positron emission tomography (PET).

  13. A Gaseous Compton Camera using a 2D-sensitive gaseous photomultiplier for Nuclear Medical Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo, C.D.R., E-mail: cdazevedo@ua.pt; Pereira, F.A.; Lopes, T.; Correia, P.M.M.; Silva, A.L.M.; Carramate, L.F.N.D.; Covita, D.S.; Veloso, J.F.C.A.

    2013-12-21

    A new Compton Camera (CC) concept based on a High Pressure Scintillation Chamber coupled to a position-sensitive Gaseous PhotoMultiplier for Nuclear Medical Imaging applications is proposed. The main goal of this work is to describe the development of a ϕ25×12cm{sup 3} cylindrical prototype, which will be suitable for scintimammography and for small-animal imaging applications. The possibility to scale it to an useful human size device is also in study. The idea is to develop a device capable to compete with the standard Anger Camera. Despite the large success of the Anger Camera, it still presents some limitations, such as: low position resolution and fair energy resolutions for 140 keV. The CC arises a different solution as it provides information about the incoming photon direction, avoiding the use of a collimator, which is responsible for a huge reduction (10{sup −4}) of the sensitivity. The main problem of the CC's is related with the Doppler Broadening which is responsible for the loss of angular resolution. In this work, calculations for the Doppler Broadening in Xe, Ar, Ne and their mixtures are presented. Simulations of the detector performance together with discussion about the gas choice are also included.

  14. Design and development of hard x-ray imaging detector using scintillator and Si photomultiplier

    Science.gov (United States)

    Goyal, S. K.; Naik, Amisha P.; Mithun, N. P. S.; Vadawale, S. V.; Acharya, Y. B.; Patel, A. R.; Ladiya, T.; Devashrayee, Niranjan M.

    2016-07-01

    There are various astrophysical phenomena which are of great importance and interest such as stellar explosions, Gamma ray bursts etc. There is also a growing interest in exploring the celestial sources in hard X-rays. High sensitive instruments are essential to perform the detailed studies of these cosmic accelerators and explosions. Hard X-ray imaging detectors having high absorption efficiency and mm spatial resolution are the key requirements to locate the generation of these astrophysical phenomenon. We hereby present a detector module which consists of a single CsI scintillation detector of size 15 x 15 x 3 mm3. The photon readout is done using an array of Silicon Photomultipliers (SiPMs). SiPM is a new development in the field of photon detection and can be described as 2D array of small (hundreds of μm2) avalanche photodiodes. We have achieved a spatial resolution of 0.5 mm with our initial setup. By using the array of these detector modules, we can build the detector with a large sensitive area with a very high spatial resolution. This paper presents the experimental details for single detector module using CsI (Tl) scintillator and SiPM and also presents the preliminary results of energy and position measurement. The GEANT4 simulation has also been carried out for the same geometry.

  15. Characterization of silicon photomultipliers at National Nano-Fab Center for PET-MR

    Science.gov (United States)

    Kim, Hyoungtaek; Sul, Woo Suk; Cho, Gyuseong

    2014-10-01

    The silicon photomultipliers (SiPMs) were fabricated for magnetic resonance compatible positron emission tomography (PET) applications using customized CMOS processes at National NanoFab Center. Each micro-cell consists of a shallow n+/p well junction on a p-type epitaxial wafer and passive quenching circuit was applied. The size of the SiPM is 3 × 3 mm2 and the pitch of each micro-cell is 65 μm. In this work, several thousands of SiPMs were packaged and tested to build a PET ring detector which has a 60 mm axial and 390 mm radial field of view. I-V characteristics of the SiPMs are shown good uniformity and breakdown voltage is around 20 V. The photon detection efficiency was measured via photon counting method and the maximum value was recorded as 16% at 470 nm. The gamma ray spectrum of a Ge-68 isotope showed nearly 10% energy resolution at 511 keV with a 3 × 3 × 20 mm3 LYSO crystal.

  16. An innovative silicon photomultiplier digitizing camera for gamma-ray astronomy

    Science.gov (United States)

    Heller, M.; Schioppa, E., Jr.; Porcelli, A.; Pujadas, I. Troyano; Ziȩtara, K.; Volpe, D. della; Montaruli, T.; Cadoux, F.; Favre, Y.; Aguilar, J. A.; Christov, A.; Prandini, E.; Rajda, P.; Rameez, M.; Bilnik, W.; Błocki, J.; Bogacz, L.; Borkowski, J.; Bulik, T.; Frankowski, A.; Grudzińska, M.; Idźkowski, B.; Jamrozy, M.; Janiak, M.; Kasperek, J.; Lalik, K.; Lyard, E.; Mach, E.; Mandat, D.; Marszałek, A.; Miranda, L. D. Medina; Michałowski, J.; Moderski, R.; Neronov, A.; Niemiec, J.; Ostrowski, M.; Paśko, P.; Pech, M.; Schovanek, P.; Seweryn, K.; Sliusar, V.; Skowron, K.; Stawarz, Ł.; Stodulska, M.; Stodulski, M.; Walter, R.; Wiȩcek, M.; Zagdański, A.

    2017-01-01

    The single-mirror small-size telescope (SST-1M) is one of the three proposed designs for the small-size telescopes (SSTs) of the Cherenkov Telescope Array (CTA) project. The SST-1M will be equipped with a 4 m-diameter segmented reflector dish and an innovative fully digital camera based on silicon photo-multipliers. Since the SST sub-array will consist of up to 70 telescopes, the challenge is not only to build telescopes with excellent performance, but also to design them so that their components can be commissioned, assembled and tested by industry. In this paper we review the basic steps that led to the design concepts for the SST-1M camera and the ongoing realization of the first prototype, with focus on the innovative solutions adopted for the photodetector plane and the readout and trigger parts of the camera. In addition, we report on results of laboratory measurements on real scale elements that validate the camera design and show that it is capable of matching the CTA requirements of operating up to high moonlight background conditions.

  17. Characterization and modeling of crosstalk and afterpulsing in Hamamatsu silicon photomultipliers

    Science.gov (United States)

    Rosado, J.; Hidalgo, S.

    2015-10-01

    The crosstalk and afterpulsing in Hamamatsu silicon photomultipliers, called Multi-Pixel Photon Counters (MPPCs), have been studied in depth. Several components of the correlated noise have been identified according to their different possible causes and their effects on the signal. In particular, we have distinguished between prompt and delayed crosstalk as well as between trap-assisted and hole-induced afterpulsing. The prompt crosstalk has been characterized through the pulse amplitude spectrum measured at dark conditions. The newest MPPC series, which incorporate isolating trenches between pixels, exhibit a very low prompt crosstalk, but a small component remains likely due to secondary photons reflected on the top surface of the device and photon-generated minority carriers diffusing in the silicon substrate.We present a meticulous procedure to characterize the afterpulsing and delayed crosstalk through the amplitude and delay time distributions of secondary pulses. Our results indicate that both noise components are due to minority carriers diffusing in the substrate and that this effect is drastically reduced in the new MPPC series as a consequence of an increase of one order of magnitude in the doping density of the substrate.Finally, we have developed a Monte Carlo simulation to study the different components of the afterpulsing and crosstalk. The simulation results support our interpretation of the experimental data. They also demonstrate that trenches longer than those employed in the Hamamatsu MPPCs would reduce the crosstalk to a much greater extent.

  18. Gain compensation technique by bias correction in arrays of Silicon Photomultipliers using fully differential fast shaper

    Science.gov (United States)

    Baszczyk, M.; Dorosz, P.; Glab, S.; Kucewicz, W.; Mik, L.; Sapor, M.

    2016-07-01

    Proposed algorithm compensates the gain by changing the bias voltage of Silicon Photomultipliers (SiPM). The signal from SiPM is amplified in fully differential preamplifier then is formed in time by the fully differential fast shaper. The compensation method was tested with four channels common cathode multi-pixel photon counter from Hamamatsu. The measurement system requires only one high voltage power supply. The polarization voltage is adjusted individually in each channel indirectly by tuning the output common mode voltage (VOCM) of fully differential amplifier. The changes of VOCM affect the input voltage through the feedback network. Actual gain of the SiPM is calculated by measuring the mean amplitude of the signal resulting from detection of single photoelectron. The VOCM is adjusted by DAC so as to reach the desired value of gain by each channel individually. The advantage of the algorithm is the possibility to set the bias of each SiPM in the array independently so they all could operate in very similar conditions (have similar gain and dark count rate). The algorithm can compensate the variations of gain of SiPM by using thermally generated pulses. There is no need to use additional current to voltage conversion which could introduce extra noises.

  19. Performance of a monolithic LaBr{sub 3}:Ce crystal coupled to an array of silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Ulyanov, Alexei, E-mail: alexey.uliyanov@ucd.ie [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Morris, Oran [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Department of Computer Science & Applied Physics, Galway-Mayo Institute of Technology, Galway (Ireland); Hanlon, Lorraine; McBreen, Sheila; Foley, Suzanne; Roberts, Oliver J.; Tobin, Isaac; Murphy, David; Wade, Colin [School of Physics, University College Dublin, Belfield, Dublin 4 (Ireland); Nelms, Nick; Shortt, Brian [European Space Agency, ESTEC, 2200 AG Noordwijk (Netherlands); Slavicek, Tomas; Granja, Carlos; Solar, Michael [Institute of Experimental and Applied Physics, Czech Technical University in Prague, 12800 Prague 2 (Czech Republic)

    2016-02-21

    A gamma-ray detector composed of a single 28×28×20 mm{sup 3} LaBr{sub 3}:Ce crystal coupled to a custom built 4×4 array of silicon photomultipliers was tested over an energy range of 30 keV to 9.3 MeV. The silicon photomultipliers were initially calibrated using 20 ns light pulses generated by a light emitting diode. The photodetector responses measured as a function of the number of incident photons were found to be non-linear and consistent with model predictions. Using corrections for the non-linearity of the silicon photomultipliers, the detector showed a linear response to gamma-rays with energies from 100 keV to the maximum available energy of 9.3 MeV. The energy resolution was found to be 4% FWHM at 662 keV. Despite the large thickness of the scintillator (20 mm) and a 5 mm thick optical window, the detector was capable of measuring the positions of the gamma-ray interaction points. The position resolution was measured at 356 keV and was found to be 8 mm FWHM in the detector plane and 11 mm FWHM for the depth of interaction. The detector can be used as a building block of a larger calorimeter system that is capable of measuring gamma-ray energies up to tens of MeV.

  20. Effect of tube size on electromagnetic tube bulging

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The commercial finite code ANSYS was employed for the simulation of the electromagnetic tube bulging process. The finite element model and boundary conditions were thoroughly discussed. ANSYS/EMAG was used to model the time varying electromagnetic field in order to obtain the radial and axial magnetic pressure acting on the tube. The magnetic pressure was then used as boundary conditions to model the high velocity deformation of various length tube with ANSYS/LSDYNA. The time space distribution of magnetic pressure on various length tubes was presented. Effect of tube size on the distribution of radial magnetic pressure and axial magnetic pressure and high velocity deformation were discussed. According to the radial magnetic pressure ratio of tube end to tube center and corresponding dimensionless length ratio of tube to coil, the free electromagnetic tube bulging was studied in classification. The calculated results show good agreements with practice.

  1. Categorising YouTube

    Directory of Open Access Journals (Sweden)

    Thomas Mosebo Simonsen

    2011-09-01

    Full Text Available This article provides a genre analytical approach to creating a typology of the User Generated Content (UGC of YouTube. The article investigates the construction of navigationprocesses on the YouTube website. It suggests a pragmatic genre approach that is expanded through a focus on YouTube’s technological affordances. Through an analysis of the different pragmatic contexts of YouTube, it is argued that a taxonomic understanding of YouTube must be analysed in regards to the vacillation of a user-driven bottom-up folksonomy and a hierarchical browsing system that emphasises a culture of competition and which favours the already popular content of YouTube. With this taxonomic approach, the UGC videos are registered and analysed in terms of empirically based observations. The article identifies various UGC categories and their principal characteristics. Furthermore, general tendencies of the UGC within the interacting relationship of new and old genres are discussed. It is argued that the utility of a conventional categorical system is primarily of analytical and theoretical interest rather than as a practical instrument.

  2. Template synthesis of test tube nanoparticles using non-destructive replication.

    Science.gov (United States)

    Wagner, Jonathan; Yao, Jingyuan; Rodgers, David; Hinds, Bruce

    2013-03-01

    Nano test tubes are a promising delivery vehicle for a range of therapeutics, including small molecule drugs and biologics. However, current template synthesis methods of producing nano test tubes are prohibitively expensive and time consuming. Here, non-destructive template replication was used to increase nano test tube yield from porous alumina by more than a hundredfold. We demonstrate how to produce nano test tubes of several sizes and compositions, including hybrid tubes with different inner and outer surfaces for targeted surface chemistry. Nano test tubes were readily suspended and stored in aqueous solutions without the need for chemical treatment. These nano test tubes should find application as delivery vehicles for therapeutics, particularly for processive 'bionanoreactors' loaded with enzymes.

  3. Tracheostomy tubes and related appliances.

    Science.gov (United States)

    Hess, Dean R

    2005-04-01

    Tracheostomy tubes are used to administer positive-pressure ventilation, to provide a patent airway, to provide protection from aspiration, and to provide access to the lower respiratory tract for airway clearance. They are available in a variety of sizes and styles, from several manufacturers. The dimensions of tracheostomy tubes are given by their inner diameter, outer diameter, length, and curvature. Differences in length between tubes of the same inner diameter, but from different manufacturers, are not commonly appreciated but may have important clinical implications. Tracheostomy tubes can be angled or curved, a feature that can be used to improve the fit of the tube in the trachea. Extra proximal length tubes facilitate placement in patients with large necks, and extra distal length tubes facilitate placement in patients with tracheal anomalies. Several tube designs have a spiral wire reinforced flexible design and have an adjustable flange design to allow bedside adjustments to meet extra-length tracheostomy tube needs. Tracheostomy tubes can be cuffed or uncuffed. Cuffs on tracheostomy tubes include high-volume low-pressure cuffs, tight-to-shaft cuffs, and foam cuffs. The fenestrated tracheostomy tube has an opening in the posterior portion of the tube, above the cuff, which allows the patient to breathe through the upper airway when the inner cannula is removed. Tracheostomy tubes with an inner cannula are called dual-cannula tracheostomy tubes. Several tracheostomy tubes are designed specifically for use with the percutaneous tracheostomy procedure. Others are designed with a port above the cuff that allows for subglottic aspiration of secretions. The tracheostomy button is used for stoma maintenance. It is important for clinicians caring for patients with a tracheostomy tube to understand the nuances of various tracheostomy tube designs and to select a tube that appropriately fits the patient.

  4. Development of an Ultrahigh Resolution Block Detector Based on 0.4 mm Pixel Ce:GAGG Scintillators and a Silicon Photomultiplier Array

    Science.gov (United States)

    Yamamoto, Seiichi; Yeom, Jung Yeol; Kamada, Kei; Endo, Takanori; Levin, Craig S.

    2013-12-01

    Ce doped Gd3Al2Ga3O12 (Ce:GAGG) is a newly developed single-crystal scintillator which has a large light output and longer emission light wavelength. The longer wavelength of the scintillation photons will produce a larger signal when coupled to typical silicon photomultiplier (Si-PM) as the quantum efficiency of semiconductor based photodetector is generally higher for light with longer wavelength. A block detector with higher spatial resolution may thus be realized by combining Ce:GAGG with Si-PM arrays. To achieve the highest possible spatial resolution for PET and SPECT detectors, we developed an ultrahigh resolution block detector using 0.4 mm × 0.4 mm × 5 mm Ce:GAGG pixels assembled to form a 24 × 24 matrix that is coupled to an Si-PM array and evaluated the performance. All Ce:GAGG pixels were separated in the 2-dimensional position histograms for Cs-137 (662 keV) gamma photons with an average peak-to-valley (P/V) ratio of 2.4. The energy resolution was 21.6% FWHM for Cs-137 (662 keV) and 23.8% for Co-57 (122 keV) gamma photons. Since Ce:GAGG does not contain naturally occurring radioisotope (Lu), beta-gamma true coincidences can be avoided and randoms are reduced when used for PET detectors. Furthermore, this property, together with its high light output and good intrinsic energy resolution, make the scintillator suited for SPECT detectors. An ultrahigh resolution PET/SPECT hybrid system might be an interesting application using Ce:GAGG/Si-PM block detectors.

  5. Analysis of ependymal ciliary beat pattern and beat frequency using high speed imaging: comparison with the photomultiplier and photodiode methods

    Directory of Open Access Journals (Sweden)

    O'Callaghan Chris

    2012-06-01

    Full Text Available Abstract Background The aim of this study was to compare beat frequency measurements of ependymal cilia made by digital high speed imaging to those obtained using the photomultiplier and modified photodiode techniques. Using high speed video analysis the relationship of the power and recover strokes was also determined. Methods Ciliated strips of ependyma attached to slices from the brain of Wistar rats were incubated at 30°C and observed using a ×50 water immersion lens. Ciliary beat frequency was measured using each of the three techniques: the high speed video, photodiode and photomultiplier. Readings were repeated after 30 minutes incubation at 37°C. Ependymal cilia were observed in slow motion and the precise movement of cilia during the recovery stroke relative to the path travelled during the power stroke was measured. Results The mean (95% confidence intervals beat frequencies determined by the high speed video, photomultiplier and photodiode at 30°C were 27.7 (26.6 to 28.8, 25.5 (24.4 to 26.6 and 20.8 (20.4 to 21.3 Hz, respectively. The mean (95% confidence intervals beat frequencies determined by the high speed video, photomultiplier and photodiode at 37°C were 36.4 (34 to 39.5, 38.4 (36.8 to 39.9 and 18.8 (16.9 to 20.5 Hz. The inter and intra observer reliability for measurement of ciliary beat frequency was 3.8% and 1%, respectively. Ependymal cilia were observed to move in a planar fashion during the power and recovery strokes with a maximum deviation to the right of the midline of 12.1(11.8 to 13.0° during the power stroke and 12.6(11.6 to 13.6° to the left of the midline during the recovery stroke. Conclusion The photodiode technique greatly underestimates ciliary beat frequency and should not be used to measure ependymal ciliary beat frequency at the temperatures studied. Ciliary beat frequency from the high speed video and photomultiplier techniques cannot be used interchangeably. Ependymal cilia had minimal deviation to

  6. Hybrid vehicles

    Energy Technology Data Exchange (ETDEWEB)

    West, J.G.W. [Electrical Machines (United Kingdom)

    1997-07-01

    The reasons for adopting hybrid vehicles result mainly from the lack of adequate range from electric vehicles at an acceptable cost. Hybrids can offer significant improvements in emissions and fuel economy. Series and parallel hybrids are compared. A combination of series and parallel operation would be the ideal. This can be obtained using a planetary gearbox as a power split device allowing a small generator to transfer power to the propulsion motor giving the effect of a CVT. It allows the engine to run at semi-constant speed giving better fuel economy and reduced emissions. Hybrid car developments are described that show the wide range of possible hybrid systems. (author)

  7. Low-cost, compact, cooled photomultiplier assembly for use in magnetic fields up to 1400 Gauss

    Science.gov (United States)

    Patch, R. W.; Tashjian, R. A.; Jentner, T. A.

    1975-01-01

    Use of vortex tube for cooling and concentric shielding have produced smaller and more compact unit than was previously available. Future uses of device could include installation in gas chromatographs and mass spectrometers. Additional uses would include measurements and controls in magnetohydrodynamic power generators and fusion reactors.

  8. Heat-shrink plastic tubing seals joints in glass tubing

    Science.gov (United States)

    Del Duca, B.; Downey, A.

    1968-01-01

    Small units of standard glass apparatus held together by short lengths of transparent heat-shrinkable polyolefin tubing. The tubing is shrunk over glass O-ring type connectors having O-rings but no lubricant.

  9. A double photomultiplier Compton camera and its readout system for mice imaging

    Energy Technology Data Exchange (ETDEWEB)

    Fontana, Cristiano Lino [Physics Department Galileo Galilei, University of Padua, Via Marzolo 8, Padova 35131 (Italy) and INFN Padova, Via Marzolo 8, Padova 35131 (Italy); Atroshchenko, Kostiantyn [Physics Department Galileo Galilei, University of Padua, Via Marzolo 8, Padova 35131 (Italy) and INFN Legnaro, Viale dell' Universita 2, Legnaro PD 35020 (Italy); Baldazzi, Giuseppe [Physics Department, University of Bologna, Viale Berti Pichat 6/2, Bologna 40127, Italy and INFN Bologna, Viale Berti Pichat 6/2, Bologna 40127 (Italy); Bello, Michele [INFN Legnaro, Viale dell' Universita 2, Legnaro PD 35020 (Italy); Uzunov, Nikolay [Department of Natural Sciences, Shumen University, 115 Universitetska str., Shumen 9712, Bulgaria and INFN Legnaro, Viale dell' Universita 2, Legnaro PD 35020 (Italy); Di Domenico, Giovanni [Physics Department, University of Ferrara, Via Saragat 1, Ferrara 44122 (Italy) and INFN Ferrara, Via Saragat 1, Ferrara 44122 (Italy)

    2013-04-19

    We have designed a Compton Camera (CC) to image the bio-distribution of gamma-emitting radiopharmaceuticals in mice. A CC employs the 'electronic collimation', i.e. a technique that traces the gamma-rays instead of selecting them with physical lead or tungsten collimators. To perform such a task, a CC measures the parameters of the Compton interaction that occurs in the device itself. At least two detectors are required: one (tracker), where the primary gamma undergoes a Compton interaction and a second one (calorimeter), in which the scattered gamma is completely absorbed. Eventually the polar angle and hence a 'cone' of possible incident directions are obtained (event with 'incomplete geometry'). Different solutions for the two detectors are proposed in the literature: our design foresees two similar Position Sensitive Photomultipliers (PMT, Hamamatsu H8500). Each PMT has 64 output channels that are reduced to 4 using a charge multiplexed readout system, i.e. a Series Charge Multiplexing net of resistors. Triggering of the system is provided by the coincidence of fast signals extracted at the last dynode of the PMTs. Assets are the low cost and the simplicity of design and operation, having just one type of device; among drawbacks there is a lower resolution with respect to more sophisticated trackers and full 64 channels Readout. This paper does compare our design of our two-Hamamatsu CC to other solutions and shows how the spatial and energy accuracy is suitable for the inspection of radioactivity in mice.

  10. Delay grid multiplexing: simple time-based multiplexing and readout method for silicon photomultipliers

    Science.gov (United States)

    Won, Jun Yeon; Ko, Guen Bae; Lee, Jae Sung

    2016-10-01

    In this paper, we propose a fully time-based multiplexing and readout method that uses the principle of the global positioning system. Time-based multiplexing allows simplifying the multiplexing circuits where the only innate traces that connect the signal pins of the silicon photomultiplier (SiPM) channels to the readout channels are used as the multiplexing circuit. Every SiPM channel is connected to the delay grid that consists of the traces on a printed circuit board, and the inherent transit times from each SiPM channel to the readout channels encode the position information uniquely. Thus, the position of each SiPM can be identified using the time difference of arrival (TDOA) measurements. The proposed multiplexing can also allow simplification of the readout circuit using the time-to-digital converter (TDC) implemented in a field-programmable gate array (FPGA), where the time-over-threshold (ToT) is used to extract the energy information after multiplexing. In order to verify the proposed multiplexing method, we built a positron emission tomography (PET) detector that consisted of an array of 4  ×  4 LGSO crystals, each with a dimension of 3  ×  3  ×  20 mm3, and one- to-one coupled SiPM channels. We first employed the waveform sampler as an initial study, and then replaced the waveform sampler with an FPGA-TDC to further simplify the readout circuits. The 16 crystals were clearly resolved using only the time information obtained from the four readout channels. The coincidence resolving times (CRTs) were 382 and 406 ps FWHM when using the waveform sampler and the FPGA-TDC, respectively. The proposed simple multiplexing and readout methods can be useful for time-of-flight (TOF) PET scanners.

  11. Delay grid multiplexing: simple time-based multiplexing and readout method for silicon photomultipliers.

    Science.gov (United States)

    Won, Jun Yeon; Ko, Guen Bae; Lee, Jae Sung

    2016-10-07

    In this paper, we propose a fully time-based multiplexing and readout method that uses the principle of the global positioning system. Time-based multiplexing allows simplifying the multiplexing circuits where the only innate traces that connect the signal pins of the silicon photomultiplier (SiPM) channels to the readout channels are used as the multiplexing circuit. Every SiPM channel is connected to the delay grid that consists of the traces on a printed circuit board, and the inherent transit times from each SiPM channel to the readout channels encode the position information uniquely. Thus, the position of each SiPM can be identified using the time difference of arrival (TDOA) measurements. The proposed multiplexing can also allow simplification of the readout circuit using the time-to-digital converter (TDC) implemented in a field-programmable gate array (FPGA), where the time-over-threshold (ToT) is used to extract the energy information after multiplexing. In order to verify the proposed multiplexing method, we built a positron emission tomography (PET) detector that consisted of an array of 4  ×  4 LGSO crystals, each with a dimension of 3  ×  3  ×  20 mm(3), and one- to-one coupled SiPM channels. We first employed the waveform sampler as an initial study, and then replaced the waveform sampler with an FPGA-TDC to further simplify the readout circuits. The 16 crystals were clearly resolved using only the time information obtained from the four readout channels. The coincidence resolving times (CRTs) were 382 and 406 ps FWHM when using the waveform sampler and the FPGA-TDC, respectively. The proposed simple multiplexing and readout methods can be useful for time-of-flight (TOF) PET scanners.

  12. Irradiation study of UV Silicon Photomultipliers for the Mu2e calorimeter

    Science.gov (United States)

    Baccaro, S.; Cemmi, A.; Cordelli, M.; Diociaiuti, E.; Donghia, R.; Ferrari, A.; Giovannella, S.; Loreti, S.; Miscetti, S.; Müller, S.; Pillon, M.; Sarra, I.

    2017-02-01

    The Mu2e calorimeter is composed of 1400 un-doped CsI crystals, coupled to large area UV extended Silicon Photomultipliers (SiPMs), arranged in two annular disks. This calorimeter has to provide precise information on energy, timing and position resolutions. It should also be fast enough to handle the high rate background and it must operate and survive in the high radiation environment. Simulation studies estimated that, in the highest irradiated regions, each photo-sensor will absorb a dose of 20 krad and will be exposed to a neutron fluency of 5.5×1011n1 MeV/cm2 in three years of running, with a safety factor of 3 included. At the end of 2015, we have concluded an irradiation campaign at the Frascati Neutron Generator (FNG, Frascati, Italy) measuring the response of two different 16 array models from Hamamatsu, which differ for the protection windows and a SiPM from FBK. In 2016, we have carried out two additional irradiation campaigns with neutrons and photons at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR, Dresden, Germany) and at the Calliope gamma irradiation facility at ENEA-Casaccia, respectively. A negligible increment of the leakage current and no gain change have been observed with the dose irradiation. On the other hand, at the end of the neutron irradiation, the gain does not show large changes whilst the leakage current increases by around a factor of 2000. In these conditions, the too high leakage current makes problematic to bias the SiPMs, thus requiring to cool them down to a running temperature of ~0oC.

  13. A detector head design for small-animal PET with silicon photomultipliers (SiPM).

    Science.gov (United States)

    Moehrs, Sascha; Del Guerra, Alberto; Herbert, Deborah J; Mandelkern, Mark A

    2006-03-07

    Small-animal PET systems are now striving for sub-millimetre resolution. Current systems based upon PSPMTs and finely pixellated scintillators can be pushed to higher resolution, but at the expense of other performance parameters and a rapidly escalating cost. Moreover, depth of interaction (DOI) information is usually difficult to assess in such systems, even though this information is highly desirable to reduce the parallax error, which is often the dominant error for such high-resolution systems. In this study we propose a high-resolution detector head for a small-animal PET imaging system with intrinsic DOI information. Instead of a pixellated scintillator, our design is based upon the classic Anger camera principle, i.e. the head is constructed of modular layers each consisting of a continuous slab of scintillator, viewed by a new type of compact silicon photodetector. The photodetector is the recently developed silicon photomultiplier (SiPM) that as well as being very compact has many other attractive properties: high gain at low bias voltage, excellent single-photoelectron resolution and fast timing. A detector head of about 4 x 4 cm2 in area is proposed, constructed from three modular layers of the type described above. We perform a simulation study, using the Monte Carlo simulation package Geant4. The simulation results are used to optimize the geometry of the detector head and characterize its performance. Additionally, hit estimation algorithms are studied to determine the interaction position of annihilation photons correctly over the whole detector surface. The resulting detector has a nearly uniform efficiency for 511 keV photons of approximately 70% and an intrinsic spatial resolution of less than approximately 0.4 mm full width at half maximum (fwhm).

  14. The Silicon Photomultiplier for application to high-resolution Positron Emission Tomography

    Science.gov (United States)

    Herbert, D. J.; Moehrs, S.; D'Ascenzo, N.; Belcari, N.; Del Guerra, A.; Morsani, F.; Saveliev, V.

    2007-04-01

    Positron Emission Tomography (PET) for small animal studies requires high-resolution gamma cameras with high sensitivity. Traditionally, inorganic scintillators are used and, in recent times, coupled to position sensitive PMTs to achieve a higher resolution. Such PSPMTs are costly, operated at high voltage and have a relatively low packing fraction. However, their advantage, compared to current solid state photodetectors, is their high signal-to-noise ratio. The Silicon Photomultiplier (SiPM) is a silicon diode detector that shows great promise as a photodetector for scintillators and hence application in nuclear medicine imaging applications. The microcell MRS (Metal-Resistor-Semiconductor) structure of the SiPM leads to a self-quenching, Geiger-mode avalanche photodiode (GAPD), that produces a large gain (5×105) at low bias voltage (50 V) and proportional output for moderate photon flux. Such a compact silicon detector, with a performance similar to a PMT, is obviously well disposed to being developed into a close-packed array in order to have a position-sensitive detection surface. We propose a miniature, high-resolution camera for a small-animal PET imaging system that is based on such an array of SiPM. The design is based upon the classic Anger camera principle; each detector module consists of a continuous slab of scintillator, viewed by a matrix of SiPM. A detector head of 4×4 cm2 in area is proposed, constructed from three such modules of the continuous camera described above. The stacked layers would give the system intrinsic depth of interaction (DOI) information. A summary of measured SiPM performance and results of a simulation of the proposed camera, using the Monte Carlo package GEANT4, are presented. It is shown that using three layers of 5 mm thick LSO, gives an efficiency of 68% with maximum count rates in the front layers. Intrinsic spatial resolution of system.

  15. Extending the dynamic range of silicon photomultipliers without increasing pixel count

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Kurtis F., E-mail: kurtis.johnson@cern.c [Department of Physics, Florida State University, Tallahassee, FL (United States)

    2010-09-21

    A silicon photomultiplier, sometimes called 'multipixel photon counter', which we here refer to as a 'SiPM', is a photo-sensitive device built from an avalanche photodiode array of pixels on a common silicon substrate, such that it can detect single photon events. The dimensions of a pixel may vary from 20 to 100 {mu}m and their density can be greater than 1000 per square millimeter. Each pixel in a SiPM operates in Geiger mode and is coupled to the output by a quenching resistor. Although each pixel operates in digital mode, the SiPM is an analog device because all the pixels are read in parallel, making it possible to generate signals within a dynamic range from a single photon to a large number of photons, ultimately limited by the number of pixels on the chip. In this note we describe a simple and general method of increasing the dynamic range of a SiPM beyond that one may naively assume from the shape of the cumulative distribution function of the SiPM response to the average number of photons per pixel. We show that by rendering the incoming flux of photons to be non-uniform in a prescribed manner, a significant increase in dynamic range is achievable. Such re-distribution of the incoming flux may be accomplished with simple, non-focusing lenses, prisms, interference films, mirrors or attenuating films. Almost any optically non-inert interceding device can increase the dynamic range of the SiPM.

  16. Downhole pulse tube refrigerators

    Energy Technology Data Exchange (ETDEWEB)

    Swift, G.; Gardner, D. [Los Alamos National Lab., NM (United States). Condensed Matter and Thermal Physics Group

    1997-12-01

    This report summarizes a preliminary design study to explore the plausibility of using pulse tube refrigeration to cool instruments in a hot down-hole environment. The original motivation was to maintain Dave Reagor`s high-temperature superconducting electronics at 75 K, but the study has evolved to include three target design criteria: cooling at 30 C in a 300 C environment, cooling at 75 K in a 50 C environment, cooling at both 75 K and 30 C in a 250 C environment. These specific temperatures were chosen arbitrarily, as representative of what is possible. The primary goals are low cost, reliability, and small package diameter. Pulse-tube refrigeration is a rapidly growing sub-field of cryogenic refrigeration. The pulse tube refrigerator has recently become the simplest, cheapest, most rugged and reliable low-power cryocooler. The authors expect this technology will be applicable downhole because of the ratio of hot to cold temperatures (in absolute units, such as Kelvin) of interest in deep drilling is comparable to the ratios routinely achieved with cryogenic pulse-tube refrigerators.

  17. The thermal tube

    Energy Technology Data Exchange (ETDEWEB)

    Semena, M.G.

    1980-08-30

    A thermal tube is proposed which contains a layer of dielectric, capillary porous material located on the internal surface of the body. To increase the heat transmitting capability, the layer of capillary porous material is made in the form of a felting, formed by hollow fibers from a non-alkaline, borosilicate glass.

  18. Prawns in Bamboo Tube

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Ingredients: 400 grams Jiwei prawns, 25 grams pork shreds, 5 grams sliced garlic. Condiments: 5 grams cooking oil, minced ginger root and scallions, cooking wine, salt, pepper and MSG (optional) Method: 1. Place the Shelled prawns into a bowl and mix with all the condiments. 2. Stuff the prawns into a fresh bamboo tube,

  19. Cladding tube manufacturing technology

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, R. [Kraftwerk Union AG, Mulheim (Germany); Jeong, Y.H.; Baek, B.J.; Kim, K.H.; Kim, S.J.; Choi, B.K.; Kim, J.M. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1999-04-01

    This report gives an overview of the manufacturing routine of PWR cladding tubes. The routine essentially consists of a series of deformation and annealing processes which are necessary to transform the ingot geometry to tube dimensions. By changing shape, microstructure and structure-related properties are altered simultaneously. First, a short overview of the basics of that part of deformation geometry is given which is related to tube reducing operations. Then those processes of the manufacturing routine which change the microstructure are depicted, and the influence of certain process parameters on microstructure and material properties are shown. The influence of the resulting microstructure on material properties is not discussed in detail, since it is described in my previous report 'Alloy Development for High Burnup Cladding.' Because of their paramount importance still up to now, and because manufacturing data and their influence on properties for other alloys are not so well established or published, the descriptions are mostly related to Zry4 tube manufacturing, and are only in short for other alloys. (author). 9 refs., 46 figs.

  20. Misdirected Minitracheostomy Tube

    Science.gov (United States)

    Singh, Ajmer; Nanda, Chinmaya; Mehta, Yatin

    2017-01-01

    We report a patient who after an uneventful coronary artery bypass graft surgery and left ventricular aneurysmorrhaphy developed intracerebral hemorrhage and subsequently required minitracheostomy. Chest X-ray showed misdirected minitracheostomy tube facing upward toward the laryngeal opening which was repositioned using bronchoscope. PMID:28074805

  1. Misdirected minitracheostomy tube

    Directory of Open Access Journals (Sweden)

    Ajmer Singh

    2017-01-01

    Full Text Available We report a patient who after an uneventful coronary artery bypass graft surgery and left ventricular aneurysmorrhaphy developed intracerebral hemorrhage and subsequently required minitracheostomy. Chest X-ray showed misdirected minitracheostomy tube facing upward toward the laryngeal opening which was repositioned using bronchoscope.

  2. Characterization of a high-resolution hybrid DOI detector for a dedicated breast PET/CT scanner

    Science.gov (United States)

    Godinez, Felipe; Chaudhari, Abhijit J.; Yang, Yongfeng; Farrell, Richard; Badawi, Ramsey D.

    2012-06-01

    The aim of this study is to design and test a new high-resolution hybrid depth of interaction (DOI) detector for a dedicated breast PET/CT scanner. Two detectors have been designed and built. The completed detectors are based on a 14 × 14 array of 1.5 × 1.5 × 20 mm3 unpolished lutetium orthosilicate scintillation crystals, with each element coated in a 50 μm layer of reflective material. The detector is read out from both ends using a position-sensitive photomultiplier tube (PSPMT) and a large active area (20 × 20 mm2) avalanche photodiode (APD) to enable acquisition of DOI information. Nuclear instrumentation modules were used to characterize the detectors’ performances in terms of timing, intrinsic spatial resolution (ISR) and energy resolution, as well as DOI resolution with a dual-ended readout configuration. Measurements with the APD were performed at a temperature of 10 °C. All crystals were identified at all depths, even though the signal amplitude from the PSPMT decreases with depth away from it. We measured a timing resolution of 2.4 ns, and an average energy resolution of 19%. The mean ISR was measured to be 1.2 mm for crystals in the central row of the array for detectors in the face-to-face position. Two off-center positions were measured corresponding to 26° and 51° oblique photon incidence, and the mean ISR at these positions was 1.5 and 1.7 mm, respectively. The average DOI resolution across all crystals and depths was measured to be 2.9 mm (including the beam width of 0.6 mm). This detector design shows good promise as a high-resolution detector for a dedicated breast PET/CT scanner.

  3. Restore condition of Incore thimble tubes in guide tubes

    Energy Technology Data Exchange (ETDEWEB)

    Solanas, A.; Izquierdo, J.

    2014-07-01

    Aging of Nuclear Power Plant and succession of outages lead to wear and twist of the thimbles tubes but also to the fooling of Incore guide tubes. These can create friction and a high strength must be used for thimble tubes withdrawal. (Author)

  4. Eustachian tube function in children after insertion of ventilation tubes.

    NARCIS (Netherlands)

    Heerbeek, N. van; Ingels, K.J.A.O.; Snik, A.F.M.; Zielhuis, G.A.

    2001-01-01

    This study was performed to assess the effect of the insertion of ventilation tubes and the subsequent aeration of the middle ear on eustachian tube (ET) function in children. Manometric ET function tests were performed repeatedly for 3 months after the placement of ventilation tubes in 83 children

  5. Enteral Tube Feeding and Pneumonia

    Science.gov (United States)

    Gray, David Sheridan; Kimmel, David

    2006-01-01

    To determine the effects of enteral tube feeding on the incidence of pneumonia, we performed a retrospective review of all clients at our institution who had gastrostomy or jejunostomy tubes placed over a 10-year period. Ninety-three subjects had a history of pneumonia before feeding tube insertion. Eighty had gastrostomy and 13, jejunostomy…

  6. Neural tube defects

    Directory of Open Access Journals (Sweden)

    M.E. Marshall

    1981-09-01

    Full Text Available Neural tube defects refer to any defect in the morphogenesis of the neural tube, the most common types being spina bifida and anencephaly. Spina bifida has been recognised in skeletons found in north-eastern Morocco and estimated to have an age of almost 12 000 years. It was also known to the ancient Greek and Arabian physicians who thought that the bony defect was due to the tumour. The term spina bifida was first used by Professor Nicolai Tulp of Amsterdam in 1652. Many other terms have been used to describe this defect, but spina bifida remains the most useful general term, as it describes the separation of the vertebral elements in the midline.

  7. Vortex tube optimization theory

    Energy Technology Data Exchange (ETDEWEB)

    Lewins, Jeffery [Cambridge Univ., Magdalene Coll., Cambridge (United Kingdom); Bejan, Adrian [Duke Univ., Dept. of Mechanical Engineering and Materials Science, Durham, NC (United States)

    1999-11-01

    The Ranque-Hilsch vortex tube splits a single high pressure stream of gas into cold and warm streams. Simple models for the vortex tube combined with regenerative precooling are given from which an optimisation can be undertaken. Two such optimisations are needed: the first shows that at any given cut or fraction of the cold stream, the best refrigerative load, allowing for the temperature lift, is nearly half the maximum loading that would result in no lift. The second optimisation shows that the optimum cut is an equal division of the vortex streams between hot and cold. Bounds are obtainable within this theory for the performance of the system for a given gas and pressure ratio. (Author)

  8. Fast identification of substance by measuring two Raman peaks with dual strip silicon photomultipliers and gated photon counting technique.

    Science.gov (United States)

    Zhang, Guoqing; Hu, Xiaobo; Cheng, Yue; Zhang, Chunling; Liu, Lina; Yang, Ru; Liang, Kun; Han, Dejun

    2011-08-20

    In this report, we use carbon tetrachloride as an example to demonstrate that substance can be quickly identified through the measurement of the two Raman peaks simply by an integrated module of dual strip silicon photomultipliers operating at room temperature in conjunction with a gated photon counting technique. Both the peak positions and the relative intensity ratio of the two Raman peaks are used to identify the substance with a reduced false acceptance rate. A complete Raman spectrum of the substance can also be measured by using this method combined with a scanning monochromator. © 2011 Optical Society of America

  9. KLauS: a low power Silicon Photomultiplier charge readout ASIC in 0.18 UMC CMOS

    Science.gov (United States)

    Briggl, K.; Chen, H.; Schimansky, D.; Shen, W.; Stankova, V.; Schultz-Coulon, H. C.

    2016-03-01

    We present the development of a low power Silicon Photomultiplier charge readout ASIC for an imaging calorimeter at a future linear collider. The analog front-end is designed to achieve sufficient signal-to-noise ratio for single pixel signals using low gain SiPMs, while allowing charge measurements over the full dynamic range of the sensors. The front-end consists of an input stage, two charge measurement branches and a fast comparator. A SAR ADC with a resolution of 10 bit digitizes the pulse height information. An additional pipelined SAR stage allows to increase the quantization resolution to 12 bit for calibration measurements.

  10. Vacuum ultra-violet and ultra-violet scintillation light detection by means of silicon photomultipliers at cryogenic temperature

    Energy Technology Data Exchange (ETDEWEB)

    Falcone, A., E-mail: andrea.falcone@pv.infn.it [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Bertoni, R. [INFN Sezione di Milano Bicocca, Piazza della Scienza, 3, 20126 Milano (Italy); Boffelli, F. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Bonesini, M. [INFN Sezione di Milano Bicocca, Piazza della Scienza, 3, 20126 Milano (Italy); Cervi, T. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); Menegolli, A. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Montanari, C.; Prata, M.C.; Rappoldi, A.; Raselli, G.L.; Rossella, M.; Simonetta, M. [INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Spanu, M. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); Torti, M. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Zani, A. [INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy)

    2015-07-01

    We tested the performance of two types of silicon photomultipliers, AdvanSiD ASD-NUV-SiPM3S-P and Hamamatsu 3×3 MM-50 UM VUV2, both at room (300 K) and at liquid nitrogen (77 K) temperature: breakdown voltage, quenching resistance, signal shape, gain and dark counts rate have been studied as function of temperature. The response of the devices to ultra-violet light is also studied. - Highlights: • We tested 2 SiPMs both at room and at cryogenic temperature. • Breakdown voltage, quenching resistance, gain and dark rate were measured. • Efficiency for VUV light detection was measured.

  11. A wandering tube.

    Science.gov (United States)

    Dubin, Ina; Gelber, Moshe; Schattner, Ami

    2016-12-05

    The predominant causes of acute mechanical small bowel obstruction in geriatric patients are adhesions and hernias, which is not much different than in other adult age groups. Unusual etiologies may be encountered, such as volvulus or gallstone ileus, but a displaced feeding gastrostomy tube is a distinctly rare cause of intestinal obstruction which needs to be considered by emergency physicians as it may be increasingly encountered.

  12. Primary fallopian tube carcinoma

    Directory of Open Access Journals (Sweden)

    Mladenović-Segedi Ljiljana

    2009-01-01

    Full Text Available Introduction. Primary fallopian tube carcinoma is extremely rare, making 0.3-1.6% of all female genital tract malignancies. Although the etymology of this tumor is unknown, it is suggested to be associated with chronic tubal inflammation, infertility, tuberculous salpingitis and tubal endometriosis. High parity is considered to be protective. Cytogenetic studies show the disease to be associated with over expression of p53, HER2/neu and c-myb. There is also some evidence that BRCA1 and BRCA2 mutations have a role in umorogeneis. Clinical features. The most prevailing symptoms with fallopian tube carcinoma are abdominal pain, abnormal vaginal discharge/bleeding and the most common finding is an adnexal mass. In many patients, fallopian tube carcinoma is asymptomatic. Diagnosis. Due to its rarity, preoperative diagnosis of primary fallopian tube carcinoma is rarely made. It is usually misdiagnosed as ovarian carcinoma, tuboovarian abscess or ectopic pregnancy. Sonographic features of the tumor are non-specific and include the presence of a fluid-filled adnexal structure with a significant solid component, a sausage-shaped mass, a cystic mass with papillary projections within, a cystic mass with cog wheel appearance and an ovoid-shaped structure containing an incomplete separation and a highly vascular solid nodule. More than 80% of patients have elevated pretreatment serum CA-125 levels, which is useful in follow-up after the definite treatment. Treatment. The treatment approach is similar to that of ovarian carcinoma, and includes total abdominal hysterectomy and bilateral salpingo-oophorectomy. Staging is followed with chemotherapy.

  13. Shape Memory Composite Hybrid Hinge

    Science.gov (United States)

    Fang, Houfei; Im, Eastwood; Lin, John; Scarborough, Stephen

    2012-01-01

    There are two conventional types of hinges for in-space deployment applications. The first type is mechanically deploying hinges. A typical mechanically deploying hinge is usually composed of several tens of components. It is complicated, heavy, and bulky. More components imply higher deployment failure probability. Due to the existence of relatively moving components among a mechanically deploying hinge, it unavoidably has microdynamic problems. The second type of conventional hinge relies on strain energy for deployment. A tape-spring hinge is a typical strain energy hinge. A fundamental problem of a strain energy hinge is that its deployment dynamic is uncontrollable. Usually, its deployment is associated with a large impact, which is unacceptable for many space applications. Some damping technologies have been experimented with to reduce the impact, but they increased the risks of an unsuccessful deployment. Coalescing strain energy components with shape memory composite (SMC) components to form a hybrid hinge is the solution. SMCs are well suited for deployable structures. A SMC is created from a high-performance fiber and a shape memory polymer resin. When the resin is heated to above its glass transition temperature, the composite becomes flexible and can be folded or packed. Once cooled to below the glass transition temperature, the composite remains in the packed state. When the structure is ready to be deployed, the SMC component is reheated to above the glass transition temperature, and it returns to its as-fabricated shape. A hybrid hinge is composed of two strain energy flanges (also called tape-springs) and one SMC tube. Two folding lines are placed on the SMC tube to avoid excessive strain on the SMC during folding. Two adapters are used to connect the hybrid hinge to its adjacent structural components. While the SMC tube is heated to above its glass transition temperature, a hybrid hinge can be folded and stays at folded status after the temperature

  14. Traveling-Wave Tubes

    Science.gov (United States)

    Kory, Carol L.

    1998-01-01

    The traveling-wave tube (TWT) is a vacuum device invented in the early 1940's used for amplification at microwave frequencies. Amplification is attained by surrendering kinetic energy from an electron beam to a radio frequency (RF) electromagnetic wave. The demand for vacuum devices has been decreased largely by the advent of solid-state devices. However, although solid state devices have replaced vacuum devices in many areas, there are still many applications such as radar, electronic countermeasures and satellite communications, that require operating characteristics such as high power (Watts to Megawatts), high frequency (below 1 GHz to over 100 GHz) and large bandwidth that only vacuum devices can provide. Vacuum devices are also deemed irreplaceable in the music industry where musicians treasure their tube-based amplifiers claiming that the solid-state and digital counterparts could never provide the same "warmth" (3). The term traveling-wave tube includes both fast-wave and slow-wave devices. This article will concentrate on slow-wave devices as the vast majority of TWTs in operation fall into this category.

  15. Balloon flight test of a Compton telescope based on scintillators with silicon photomultiplier readouts

    Energy Technology Data Exchange (ETDEWEB)

    Bloser, P.F., E-mail: Peter.Bloser@unh.edu; Legere, J.S.; Bancroft, C.M.; Ryan, J.M.; McConnell, M.L.

    2016-03-11

    We present the results of the first high-altitude balloon flight test of a concept for an advanced Compton telescope making use of modern scintillator materials with silicon photomultiplier (SiPM) readouts. There is a need in the fields of high-energy astronomy and solar physics for new medium-energy gamma-ray (~0.4–10 MeV) detectors capable of making sensitive observations of both line and continuum sources over a wide dynamic range. A fast scintillator-based Compton telescope with SiPM readouts is a promising solution to this instrumentation challenge, since the fast response of the scintillators permits both the rejection of background via time-of-flight (ToF) discrimination and the ability to operate at high count rates. The Solar Compton Telescope (SolCompT) prototype presented here was designed to demonstrate stable performance of this technology under balloon-flight conditions. The SolCompT instrument was a simple two-element Compton telescope, consisting of an approximately one-inch cylindrical stilbene crystal for a scattering detector and a one-inch cubic LaBr{sub 3}:Ce crystal for a calorimeter detector. Both scintillator detectors were read out by 2×2 arrays of Hamamatsu S11828-3344 MPPC devices. Custom front-end electronics provided optimum signal rise time and linearity, and custom power supplies automatically adjusted the SiPM bias voltage to compensate for temperature-induced gain variations. A tagged calibration source, consisting of ~240 nCi of {sup 60}Co embedded in plastic scintillator, was placed in the field of view and provided a known source of gamma rays to measure in flight. The SolCompT balloon payload was launched on 24 August 2014 from Fort Sumner, NM, and spent ~3.75 h at a float altitude of ~123,000 ft. The instrument performed well throughout the flight. After correcting for small (~10%) residual gain variations, we measured an in-flight ToF resolution of ~760 ps (FWHM). Advanced scintillators with SiPM readouts continue to show

  16. Bismuth germanate coupled to near ultraviolet silicon photomultipliers for time-of-flight PET.

    Science.gov (United States)

    Kwon, Sun Il; Gola, Alberto; Ferri, Alessandro; Piemonte, Claudio; Cherry, Simon R

    2016-09-21

    Bismuth germanate (BGO) was a very attractive scintillator in early-generation positron emission tomography (PET) scanners. However, the major disadvantages of BGO are lower light yield and longer rise and decay time compared to currently popular scintillators such as LSO and LYSO. This results in poorer coincidence timing resolution and it has generally been assumed that BGO is not a suitable scintillator for time-of-flight (TOF) PET applications. However, when a 511 keV photon interacts in a scintillator, a number of Cerenkov photons are produced promptly by energetic electrons released by photoelectric or Compton interactions. If these prompt photons can be captured, they could provide a better timing trigger for PET. Since BGO has a high refractive index (increasing the Cerenkov light yield) and excellent optical transparency down to 320 nm (Cerenkov light yield is higher at shorter wavelengths), we hypothesized that the coincidence timing resolution of BGO can be significantly improved by efficient detection of the Cerenkov photons. However, since the number of Cerenkov photons is far less than the number of scintillation photons, and they are more abundant in the UV and blue part of the spectrum, photosensors need to have high UV/blue sensitivity, fast temporal response, and very low noise in order to trigger on the faint Cerenkov signal. In this respect, NUV-HD silicon photomultipliers (SiPMs) (FBK, Trento, Italy) are an excellent fit for our approach. In this study, coincidence events were measured using BGO crystals coupled with NUV-HD SiPMs. The existence and influence of Cerenkov photons on the timing measurements were studied using different configurations to exploit the directionality of the Cerenkov emissions. Coincidence resolving time values (FWHM) of ~270 ps from 2  ×  3  ×  2 mm(3) BGO crystals and ~560 ps from 3  ×  3  ×  20 mm(3) BGO crystals were obtained. To our knowledge, these are the best

  17. A Study of Position-Sensitive Solid-State Photomultiplier Signal Properties.

    Science.gov (United States)

    Schmall, Jeffrey P; Du, Junwei; Judenhofer, Martin S; Dokhale, Purushottam; Christian, James; McClish, Mickel; Shah, Kanai S; Cherry, Simon R

    2014-06-12

    We present an analysis of the signal properties of a position-sensitive solid-state photomultiplier (PS-SSPM) that has an integrated resistive network for position sensing. Attractive features of PS-SSPMs are their large area and ability to resolve small scintillator crystals. However, the large area leads to a high detector capacitance, and in order to achieve high spatial resolution a large network resistor value is required. These inevitably create a low-pass filter that drastically slows what would be a fast micro-cell discharge pulse. Significant changes in the signal shape of the PS-SSPM cathode output as a function of position are observed, which result in a position-dependent time delay when using traditional time pick-off methods such as leading edge discrimination and constant fraction discrimination. The timing resolution and time delay, as a function of position, were characterized for two different PS-SSPM designs, a continuous 10 mm × 10 mm PS-SSPM and a tiled 2 × 2 array of 5 mm × 5 mm PS-SSPMs. After time delay correction, the block timing resolution, measured with a 6 × 6 array of 1.3 × 1.3 × 20 mm(3) LSO crystals, was 8.6 ns and 8.5 ns, with the 10 mm PS-SSPM and 5 mm PS-SSPM respectively. The effect of crystal size on timing resolution was also studied, and contrary to expectation, a small improvement was measured when reducing the crystal size from 1.3 mm to 0.5 mm. Digital timing methods were studied and showed great promise for allowing accurate timing by implementation of a leading edge time pick-off. Position-dependent changes in signal shape on the anode side also are present, which complicates peak height data acquisition methods used for positioning. We studied the effect of trigger position on signal amplitude, flood histogram quality, and depth-of-interaction resolution in a dual-ended readout detector configuration. We conclude that detector timing and positioning can be significantly improved by implementation of digital timing

  18. Evaluation of Matrix9 silicon photomultiplier array for small-animal PET

    Science.gov (United States)

    Du, Junwei; Schmall, Jeffrey P.; Yang, Yongfeng; Di, Kun; Roncali, Emilie; Mitchell, Gregory S.; Buckley, Steve; Jackson, Carl; Cherry, Simon R.

    2015-01-01

    Purpose: The MatrixSL-9-30035-OEM (Matrix9) from SensL is a large-area silicon photomultiplier (SiPM) photodetector module consisting of a 3 × 3 array of 4 × 4 element SiPM arrays (total of 144 SiPM pixels) and incorporates SensL’s front-end electronics board and coincidence board. Each SiPM pixel measures 3.16 × 3.16 mm2 and the total size of the detector head is 47.8 × 46.3 mm2. Using 8 × 8 polished LSO/LYSO arrays (pitch 1.5 mm) the performance of this detector system (SiPM array and readout electronics) was evaluated with a view for its eventual use in small-animal positron emission tomography (PET). Methods: Measurements of noise, signal, signal-to-noise ratio, energy resolution, flood histogram quality, timing resolution, and array trigger error were obtained at different bias voltages (28.0–32.5 V in 0.5 V intervals) and at different temperatures (5 °C–25 °C in 5 °C degree steps) to find the optimal operating conditions. Results: The best measured signal-to-noise ratio and flood histogram quality for 511 keV gamma photons were obtained at a bias voltage of 30.0 V and a temperature of 5 °C. The energy resolution and timing resolution under these conditions were 14.2% ± 0.1% and 4.2 ± 0.1 ns, respectively. The flood histograms show that all the crystals in the 1.5 mm pitch LSO array can be clearly identified and that smaller crystal pitches can also be resolved. Flood histogram quality was also calculated using different center of gravity based positioning algorithms. Improved and more robust results were achieved using the local 9 pixels for positioning along with an energy offset calibration. To evaluate the front-end detector readout, and multiplexing efficiency, an array trigger error metric is introduced and measured at different lower energy thresholds. Using a lower energy threshold greater than 150 keV effectively eliminates any mispositioning between SiPM arrays. Conclusions: In summary, the Matrix9 detector system can resolve

  19. Sensitivity encoded silicon photomultiplier--a new sensor for high-resolution PET-MRI.

    Science.gov (United States)

    Schulz, Volkmar; Berker, Yannick; Berneking, Arne; Omidvari, Negar; Kiessling, Fabian; Gola, Alberto; Piemonte, Claudio

    2013-07-21

    Detectors for simultaneous positron emission tomography and magnetic resonance imaging in particular with sub-mm spatial resolution are commonly composed of scintillator crystal arrays, readout via arrays of solid state sensors, such as avalanche photo diodes (APDs) or silicon photomultipliers (SiPMs). Usually a light guide between the crystals and the sensor is used to enable the identification of crystals which are smaller than the sensor elements. However, this complicates crystal identification at the gaps and edges of the sensor arrays. A solution is to use as many sensors as crystals with a direct coupling, which unfortunately increases the complexity and power consumption of the readout electronics. Since 1997, position-sensitive APDs have been successfully used to identify sub-mm crystals. Unfortunately, these devices show a limitation in their time resolution and a degradation of spatial resolution when placed in higher magnetic fields. To overcome these limitations, this paper presents a new sensor concept that extends conventional SiPMs by adding position information via the spatial encoding of the channel sensitivity. The concept allows a direct coupling of high-resolution crystal arrays to the sensor with a reduced amount of readout channels. The theory of sensitivity encoding is detailed and linked to compressed sensing to compute unique sparse solutions. Two devices have been designed using one- and two-dimensional linear sensitivity encoding with eight and four readout channels, respectively. Flood histograms of both devices show the capability to precisely identify all 4 × 4 LYSO crystals with dimensions of 0.93 × 0.93 × 10 mm(3). For these crystals, the energy and time resolution (MV ± SD) of the devices with one (two)-dimensional encoding have been measured to be 12.3 · (1 ± 0.047)% (13.7 · (1 ± 0.047)%) around 511 keV with a paired coincidence time resolution (full width at half maximum) of 462 · (1 ± 0.054) ps (452 · (1 ± 0

  20. Bismuth germanate coupled to near ultraviolet silicon photomultipliers for time-of-flight PET

    Science.gov (United States)

    Kwon, Sun Il; Gola, Alberto; Ferri, Alessandro; Piemonte, Claudio; Cherry, Simon R.

    2016-09-01

    Bismuth germanate (BGO) was a very attractive scintillator in early-generation positron emission tomography (PET) scanners. However, the major disadvantages of BGO are lower light yield and longer rise and decay time compared to currently popular scintillators such as LSO and LYSO. This results in poorer coincidence timing resolution and it has generally been assumed that BGO is not a suitable scintillator for time-of-flight (TOF) PET applications. However, when a 511 keV photon interacts in a scintillator, a number of Cerenkov photons are produced promptly by energetic electrons released by photoelectric or Compton interactions. If these prompt photons can be captured, they could provide a better timing trigger for PET. Since BGO has a high refractive index (increasing the Cerenkov light yield) and excellent optical transparency down to 320 nm (Cerenkov light yield is higher at shorter wavelengths), we hypothesized that the coincidence timing resolution of BGO can be significantly improved by efficient detection of the Cerenkov photons. However, since the number of Cerenkov photons is far less than the number of scintillation photons, and they are more abundant in the UV and blue part of the spectrum, photosensors need to have high UV/blue sensitivity, fast temporal response, and very low noise in order to trigger on the faint Cerenkov signal. In this respect, NUV-HD silicon photomultipliers (SiPMs) (FBK, Trento, Italy) are an excellent fit for our approach. In this study, coincidence events were measured using BGO crystals coupled with NUV-HD SiPMs. The existence and influence of Cerenkov photons on the timing measurements were studied using different configurations to exploit the directionality of the Cerenkov emissions. Coincidence resolving time values (FWHM) of ~270 ps from 2  ×  3  ×  2 mm3 BGO crystals and ~560 ps from 3  ×  3  ×  20 mm3 BGO crystals were obtained. To our knowledge, these are the best

  1. Study of the silicon photomultipliers and their applications in positron emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Chen

    2014-05-15

    This thesis deals with silicon photomultipliers (SiPM) used in scintillation detectors and their applications in positron emission tomography (PET). The study of the SiPM is mainly focused on the application to the proposed EndoTOFPET-US detector, which is a multi-modality PET detector facilitating the development of new biomarkers for pancreas and prostate cancers. A Monte Carlo simulation tool is developed for the optimization of the detector's single channel design. In order to obtain a 200 ps system coincidence time resolution and maximize the detector sensitivity, the requirements for the crystal geometry, light yield and SiPM photon detection efficiency are specified based on the simulation study. In addition, the nonlinear response of the SiPM can be corrected by the simulation tool and the energy resolution of the detector is extracted. A series of measurements are established to characterize SiPMs in a fast and reliable way with high precision. The static characterization measures the value of different components in the derived electrical model of the SiPM, whereas the dynamic characterization extracts parameters that is crucial for the operation of the SiPM. Several SiPM samples are tested and their characteristics are compared. The developed setup and the precision of the measurement fulfill the requirements of the quality assurance test for the commissioning of the EndoTOFPET-US detector. The test foresees large quantities of SiPMs to be characterized. In addition, the developed measuring procedure has contributed to the study of X-ray induced surface damage of a SiPM from Hamamatsu. Characteristics of the device are measured before and after irradiating the SiPM with different X-ray doses, the results are compared and discussed. A comparative study of a digital and an analog SiPM in gamma spectroscopy with the inorganic scintillator is presented. The characteristics of a prototype digital SiPM that is developed for the EndoTOFPETUS detector is

  2. Reliability of steam generator tubing

    Energy Technology Data Exchange (ETDEWEB)

    Kadokami, E. [Mitsubishi Heavy Industries Ltd., Hyogo-ku (Japan)

    1997-02-01

    The author presents results on studies made of the reliability of steam generator (SG) tubing. The basis for this work is that in Japan the issue of defects in SG tubing is addressed by the approach that any detected defect should be repaired, either by plugging the tube or sleeving it. However, this leaves open the issue that there is a detection limit in practice, and what is the effect of nondetectable cracks on the performance of tubing. These studies were commissioned to look at the safety issues involved in degraded SG tubing. The program has looked at a number of different issues. First was an assessment of the penetration and opening behavior of tube flaws due to internal pressure in the tubing. They have studied: penetration behavior of the tube flaws; primary water leakage from through-wall flaws; opening behavior of through-wall flaws. In addition they have looked at the question of the reliability of tubing with flaws during normal plant operation. Also there have been studies done on the consequences of tube rupture accidents on the integrity of neighboring tubes.

  3. 东方百合杂种后代试管苗叶片总DNA提取方法的选择%Choosing Suitable Method to Extract Genomic DNA from the Leaves of In-tube Seedling of the Hybrid Offspring of Oriental Lily

    Institute of Scientific and Technical Information of China (English)

    胡凤荣; 国荣荣; 王斐; 王江勇

    2013-01-01

      以东方百合‘Sorbonne’בFrancia’的杂种后代试管苗叶片为材料,采用CTAB-高盐法、简易CTAB法、CTAB-硅珠法和SDS-CTAB法等4种DNA提取方法,比较DNA耗时、纯度、得率、浓度和质量等指标,以期为东方百合‘Sorbonne’בFrancia’杂种群体大量杂种后代试管苗叶片总DNA的提取筛选适宜方法.结果表明,除CTAB-硅珠法未获得DNA,其余3种方法均获得条带清晰、完整性好的DNA.在耗时方面, CTAB-硅珠法<简易CTAB法tube seedling of oriental lily, the hybrids offspring derived from the cross of Sorbonne × Francia were used as the experimental materials in this study. We compared the DAN quality and extracting efficiency of the employed DNA extraction methods, such as SDS-CTAB, Simple and ease CTAB, CTAB-high salt precipitation and CTAB-silica purifi-cation, in the facets of the purity, yield, concentration, and time consuming to choosing the ideal DNA extraction method. Three methods can be used to extract DNA with good banding profiles and Integrity except CTAB-silica purification missing DNA. The orders of the time consuming were from more to less following as CTAB-silica purification, Simple and ease CTAB, CTAB-high salt precipitation and SDS-CTAB. In the term of DNA purity, the simple CTAB method got the highest DNA purity than that of the SDS-CTAB and CTAB-high salt precipitation, which the extracted DNA with the excellent quality with OD260/OD280, 1.98, OD260/OD230, 2.01;while the concentration of the extracted DNA reached 190.01 ng/μL as well as 57.01μg/g of the DNA yield. Above all, Simple and

  4. Pollen germination and pollen tube growth in ZP maize lines

    Directory of Open Access Journals (Sweden)

    Cerović Radosav

    2014-01-01

    Full Text Available The study was conducted on the in vitro pollen germination at 26°, 28°, 32° and 35°C for 24h of male parental lines, pollen tube growth in vivo in cross pollination of female and male parental lines that make couples in four hybrids: ZP 504 su (♀ ZPPL 51 × ♂ ZPPL 67; ZP 677 (♀ ZPPL 17 × ♂ ZPPL 201; ZP 704 (♀ ZPPL 109 × ♂ ZPPL 79, ZP 611 k (♀ ZPPL 126 × ♂ ZPPL 105, and the open pollination of female parental lines of the above mentioned hybrids. Pollen germination in vitro and pollen tube growth dynamics in vivo showed different genotypic specificities with the tests applied. The obtained results were discussed in the context of reproductive biology of ZP maize lines and aimed to create the preconditions for successful management and direction of the process in practice - seed production in certain environmental conditions.

  5. The statistical distribution of the number of counted scintillation photons in digital silicon photomultipliers: model and validation.

    Science.gov (United States)

    van Dam, Herman T; Seifert, Stefan; Schaart, Dennis R

    2012-08-07

    In the design and application of scintillation detectors based on silicon photomultipliers (SiPMs), e.g. in positron emission tomography imaging, it is important to understand and quantify the non-proportionality of the SiPM response due to saturation, crosstalk and dark counts. A new type of SiPM, the so-called digital silicon photomultiplier (dSiPM), has recently been introduced. Here, we develop a model of the probability distribution of the number of fired microcells, i.e. the number of counted scintillation photons, in response to a given amount of energy deposited in a scintillator optically coupled to a dSiPM. Based on physical and functional principles, the model elucidates the statistical behavior of dSiPMs. The model takes into account the photon detection efficiency of the detector; the light yield, excess variance and time profile of the scintillator; and the crosstalk probability, dark count rate, integration time and the number of microcells of the dSiPM. Furthermore, relations for the expectation value and the variance of the number of fired cells are deduced. These relations are applied in the experimental validation of the model using a dSiPM coupled to a LSO:Ce,Ca scintillator. Finally, we propose an accurate method for the correction of energy spectra measured with dSiPM-based scintillation detectors.

  6. Time resolution of Burle 85001 micro-channel plate photo-multipliers in comparison with Hamamatsu R2083

    Energy Technology Data Exchange (ETDEWEB)

    V. Baturin; V. Burkert; W. Kim; S. Majewsky; D. Nekrasov; K. Park; V. Popov; E. S. Smith; D. Son; S. S. Stepanyan; C. Zorn

    2005-06-01

    The CLAS detector will require improvements in its particle identification system to take advantage of the higher energies provided by the Jefferson Laboratory accelerator upgrade to 12 GeV. To this end, we have studied the timing characteristics of the micro-channel plate photo-multiplier 85001 from Burle, which can be operated in a high magnetic field environment. For reference and comparison, measurements were also made using the standard PMT R2083 from Hamamatsu using two timing methods. The cosmic ray method, which utilizes three identical scintillating counters 2cm x 3cm x 50cm with PMs at the ends, yields 59.1(0.7)ps. The location method of particles from radiative source with known coordinates has been used to compare timing resolutions of R2083 and Burle-85001. This ''coordinate method'' requires only one counter instrumented with two PMs and it yields 59.5(0.7)ps. For the micro-channel plate photomultiplier from Burle with an external amplification of 10 to the signals, the co ordinate method yields 130(4)ps. This method also makes it possible to estimate the number of primary photo-electrons.

  7. Deformation Characterization of Friction-Stir-Welded Tubes by Hydraulic Bulge Testing

    Science.gov (United States)

    Pang, Q.; Hu, Z. L.; Pan, X.; Zuo, X. Q.

    2014-10-01

    In this article, the large-diameter thin-walled aluminum alloy tubes were produced using a hybrid process combining friction-stir welding (FSW) and spinning. For this novel process, rolled aluminum alloy sheets with a thickness about 2-3 times the wall thickness of target tube, were FSW to form cylinders, and then the cylinders were subjected to spinning to get thin-walled aluminum alloy tubes. Both experimental and simulation study were conducted to investigate the deformation characterization of the FSW tube during hydraulic bulge testing, and the stress and strain states and thickness distribution of the FSW tube were investigated. It was found that the common defects of FSW tube can be significantly improved by specific welding devices. The ductility of the tube is considerably improved with nearly two times higher bulge ratio than as-spun tube after annealing treatment at 300°C. But the annealed tube still shows a high nonuniform wall thickness distribution due to the inhomogeneous deformation characteristics. With increasing deformation of the tube, the gap between the hoop and axial stress for the weld and base metal (BM) decreases. However, the hoop and axial stress of the weld are always greater than those of the BM at the same pressure.

  8. Study of the photomultiplier R7600-00-M4 for the purpose of the electromagnetic calorimeter in the AMS-02 experiment

    CERN Document Server

    Kossakowski, R; Dubois, J M; Fougeron, D; Hermel-Richard; Sottile, R; Vialle, J P

    2002-01-01

    The properties of the 4-channels photomultiplier R7600-00-M4 from Hamamatsu were extensively studied for use in the AMS-02 electromagnetic calorimeter. A scan of the photocathode with a precision in position better than 0.1 mm was performed in order to measure the position dependence of the sensitivity and of the cross talk between pixels. The influence of the magnetic field applied in X, Y and Z directions was measured. The dynamic range of the photomultiplier was measured and optimized by the appropriate choice of the high voltage divider and of the value of the high voltage.

  9. Study of the photomultiplier R7600-00-M4 for the purpose of the electromagnetic calorimeter in the AMS-02 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kossakowski, Roman; Audemer, Jean Charles; Dubois, Jean Marc; Fougeron, Denis; Hermel Richard; Sottile, Rico; Vialle, Jean Pierre [Laboratoire d' Annecy-Le-Vieux de Physique des Particules, LAPP, IN2P3-CNRS, BP 110, F-74941 Annecy-Le-Vieux (France)

    2002-07-01

    The properties of the 4-channels photomultiplier R7600-00-M4 from Hamamatsu were extensively studied for use in the AMS-02 electromagnetic calorimeter. A scan of the photocathode with a precision in position better than 0.1 mm was performed in order to measure the position dependence of the sensitivity and of the cross talk between pixels. The influence of the magnetic field applied in X, Y and Z directions was measured. The dynamic range of the photomultiplier was measured and optimized by the appropriate choice of the high voltage divider and of the value of the high voltage. (authors)

  10. Lava Tube Collapse Pits

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] We will be looking at collapse pits for the next two weeks. Collapse pits on Mars are formed in several ways. In volcanic areas, channelized lava flows can form roofs which insulate the flowing lava. These features are termed lava tubes on Earth and are common features in basaltic flows. After the lava has drained, parts of the roof of the tube will collapse under its own weight. These collapse pits will only be as deep as the bottom of the original lava tube. Another type of collapse feature associated with volcanic areas arises when very large eruptions completely evacuate the magma chamber beneath the volcano. The weight of the volcano will cause the entire edifice to subside into the void space below it. Structural features including fractures and graben will form during the subsidence. Many times collapse pits will form within the graben. In addition to volcanic collapse pits, Mars has many collapse pits formed when volatiles (such as subsurface ice) are released from the surface layers. As the volatiles leave, the weight of the surrounding rock causes collapse pits to form. These collapse pits are found in the southern hemisphere of Mars. They are likely lava tube collapse pits related to flows from Hadriaca Patera. Image information: VIS instrument. Latitude -36.8, Longitude 89.6 East (270.4 West). 19 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D

  11. Hybrid Metaheuristics

    CERN Document Server

    2013-01-01

    The main goal of this book is to provide a state of the art of hybrid metaheuristics. The book provides a complete background that enables readers to design and implement hybrid metaheuristics to solve complex optimization problems (continuous/discrete, mono-objective/multi-objective, optimization under uncertainty) in a diverse range of application domains. Readers learn to solve large scale problems quickly and efficiently combining metaheuristics with complementary metaheuristics, mathematical programming, constraint programming and machine learning. Numerous real-world examples of problems and solutions demonstrate how hybrid metaheuristics are applied in such fields as networks, logistics and transportation, bio-medical, engineering design, scheduling.

  12. Tube coalescence in the Jingfudong lava tube and implications for lava flow hazard of Tengchong volcanism

    OpenAIRE

    Zhengquan Chen; Yongshun Liu; Haiquan Wei; Jiandong Xu; Wenfeng Guo

    2016-01-01

    Tube-fed structure occurs as a general phenomenon in Tengchong basic lavas, such as lava tubes, lava plugs and tube-related collapse depressions. We deduced the development of Laoguipo lava flows, which is the longest lava tube (Jingfudong lava tube) evolved in Tengchong volcanic area. Following the detailed documentation of the tube morphology of the Jingfudong lava tube, we propose that the Jingfudong lava tube was formed through vertical coalescence of at least three tubes. The coalescence...

  13. Evaluation of Matrix9 silicon photomultiplier array for small-animal PET

    Energy Technology Data Exchange (ETDEWEB)

    Du, Junwei, E-mail: jwdu@ucdavis.edu; Schmall, Jeffrey P.; Yang, Yongfeng; Di, Kun; Roncali, Emilie; Mitchell, Gregory S. [Department of Biomedical Engineering, University of California-Davis, One Shields Avenue, Davis, California 95616 (United States); Buckley, Steve; Jackson, Carl [SensL Technologies Ltd., 6800 Airport Business Park, Cork (Ireland); Cherry, Simon R. [Department of Biomedical Engineering, University of California-Davis, One Shields Avenue, Davis, California, 95616 (United States)

    2015-02-15

    Purpose: The MatrixSL-9-30035-OEM (Matrix9) from SensL is a large-area silicon photomultiplier (SiPM) photodetector module consisting of a 3 × 3 array of 4 × 4 element SiPM arrays (total of 144 SiPM pixels) and incorporates SensL’s front-end electronics board and coincidence board. Each SiPM pixel measures 3.16 × 3.16 mm{sup 2} and the total size of the detector head is 47.8 × 46.3 mm{sup 2}. Using 8 × 8 polished LSO/LYSO arrays (pitch 1.5 mm) the performance of this detector system (SiPM array and readout electronics) was evaluated with a view for its eventual use in small-animal positron emission tomography (PET). Methods: Measurements of noise, signal, signal-to-noise ratio, energy resolution, flood histogram quality, timing resolution, and array trigger error were obtained at different bias voltages (28.0–32.5 V in 0.5 V intervals) and at different temperatures (5 °C–25 °C in 5 °C degree steps) to find the optimal operating conditions. Results: The best measured signal-to-noise ratio and flood histogram quality for 511 keV gamma photons were obtained at a bias voltage of 30.0 V and a temperature of 5 °C. The energy resolution and timing resolution under these conditions were 14.2% ± 0.1% and 4.2 ± 0.1 ns, respectively. The flood histograms show that all the crystals in the 1.5 mm pitch LSO array can be clearly identified and that smaller crystal pitches can also be resolved. Flood histogram quality was also calculated using different center of gravity based positioning algorithms. Improved and more robust results were achieved using the local 9 pixels for positioning along with an energy offset calibration. To evaluate the front-end detector readout, and multiplexing efficiency, an array trigger error metric is introduced and measured at different lower energy thresholds. Using a lower energy threshold greater than 150 keV effectively eliminates any mispositioning between SiPM arrays. Conclusions: In summary, the Matrix9 detector system

  14. Steam generator tube integrity program

    Energy Technology Data Exchange (ETDEWEB)

    Dierks, D.R.; Shack, W.J. [Argonne National Laboratory, IL (United States); Muscara, J.

    1996-03-01

    A new research program on steam generator tubing degradation is being sponsored by the U.S. Nuclear Regulatory Commission (NRC) at Argonne National Laboratory. This program is intended to support a performance-based steam generator tube integrity rule. Critical areas addressed by the program include evaluation of the processes used for the in-service inspection of steam generator tubes and recommendations for improving the reliability and accuracy of inspections; validation and improvement of correlations for evaluating integrity and leakage of degraded steam generator tubes, and validation and improvement of correlations and models for predicting degradation in steam generator tubes as aging occurs. The studies will focus on mill-annealed Alloy 600 tubing, however, tests will also be performed on replacement materials such as thermally-treated Alloy 600 or 690. An overview of the technical work planned for the program is given.

  15. LUCID A Cherenkov Tube Based Detector for Monitoring the ATLAS Experiment Luminosity

    CERN Document Server

    Sbrizzi, A

    2007-01-01

    The LUCID (LUminosity Cherenkov Integrating Detector) apparatus is composed by two symmetric arms deployed at about 17 m from the ATLAS interaction point. The purpose of this detector, which will be installed in january 2008, is to monitor the luminosity delivered by the LHC machine to the ATLAS experiment. An absolute luminosity calibration is needed and it will be provided by a Roman Pot type detector with the two arms placed at about 240 m from the interaction point. Each arm of the LUCID detector is based on an aluminum vessel containing 20 Cherenkov tubes, 15 mm diameter and 1500 mm length, filled with C4F10 radiator gas at 1.5 bar. The Cherenkov light generated by charged particles above the threshold is collected by photomultiplier tubes (PMT) directly placed at the tubes end. The challenging aspect of this detector is its readout in an environment characterized by the high dose of radiation (about 0.7 Mrad/year at 10^33cm^2 s^-1) it must withstand. In order to fulfill these radiation hardness requirem...

  16. Diffusion in a Curved Tube

    OpenAIRE

    Ogawa, Naohisa

    2011-01-01

    The diffusion of particles in confining walls forming a tube is discussed. Such a transport phenomenon is observed in biological cells and porous media. We consider the case in which the tube is winding with curvature and torsion, and the thickness of the tube is sufficiently small compared with its curvature radius. We discuss how geomerical quantities appear in a quasi-one-dimensional diffusion equation.

  17. The special relativistic shock tube

    Science.gov (United States)

    Thompson, Kevin W.

    1986-01-01

    The shock-tube problem has served as a popular test for numerical hydrodynamics codes. The development of relativistic hydrodynamics codes has created a need for a similar test problem in relativistic hydrodynamics. The analytical solution to the special relativistic shock-tube problem is presented here. The relativistic shock-jump conditions and rarefaction solution which make up the shock tube are derived. The Newtonian limit of the calculations is given throughout.

  18. Tubing for augmented heat transfer

    Energy Technology Data Exchange (ETDEWEB)

    Yampolsky, J.S.; Pavlics, P.

    1983-08-01

    The objectives of the program reported were: to determine the heat transfer and friction characteristics on the outside of spiral fluted tubing in single phase flow of water, and to assess the relative cost of a heat exchanger constructed with spiral fluted tubing with one using conventional smooth tubing. An application is examined where an isolation water/water heat exchanger was used to transfer the heat from a gaseous diffusion plant to an external system for energy recovery. (LEW)

  19. Alternate tube plugging criteria for steam generator tubes

    Energy Technology Data Exchange (ETDEWEB)

    Cueto-Felgueroso, C.; Aparicio, C.B. [Tecnatom, S.A., Madrid (Spain)

    1997-02-01

    The tubing of the Steam Generators constitutes more than half of the reactor coolant pressure boundary. Specific requirements governing the maintenance of steam generator tubes integrity are set in Plant Technical Specifications and in Section XI of the ASME Boiler and Pressure Vessel Code. The operating experience of Steam Generator tubes of PWR plants has shown the existence of some types of degradatory processes. Every one of these has an specific cause and affects one or more zones of the tubes. In the case of Spanish Power Plants, and depending on the particular Plant considered, they should be mentioned the Primary Water Stress Corrosion Cracking (PWSCC) at the roll transition zone (RTZ), the Outside Diameter Stress Corrosion Cracking (ODSCC) at the Tube Support Plate (TSP) intersections and the fretting with the Anti-Vibration Bars (AVBs) or with the Support Plates in the preheater zone. The In-Service Inspections by Eddy Currents constitutes the standard method for assuring the SG tubes integrity and they permit the monitoring of the defects during the service life of the plant. When the degradation reaches a determined limit, called the plugging limit, the SG tube must be either repaired or retired from service by plugging. Customarily, the plugging limit is related to the depth of the defect. Such depth is typically 40% of the wall thickness of the tube and is applicable to any type of defect in the tube. In its origin, that limit was established for tubes thinned by wastage, which was the predominant degradation in the seventies. The application of this criterion for axial crack-like defects, as, for instance, those due to PWSCC in the roll transition zone, has lead to an excessive and unnecessary number of tubes being plugged. This has lead to the development of defect specific plugging criteria. Examples of the application of such criteria are discussed in the article.

  20. Learning from YouTube [Video Book

    Science.gov (United States)

    Juhasz, Alexandra

    2011-01-01

    YouTube is a mess. YouTube is for amateurs. YouTube dissolves the real. YouTube is host to inconceivable combos. YouTube is best for corporate-made community. YouTube is badly baked. These are a few of the things Media Studies professor Alexandra Juhasz (and her class) learned about YouTube when she set out to investigate what actually happens…

  1. Hybrid intermediaries

    OpenAIRE

    Cetorelli, Nicola

    2014-01-01

    I introduce the concept of hybrid intermediaries: financial conglomerates that control a multiplicity of entity types active in the "assembly line" process of modern financial intermediation, a system that has become known as shadow banking. The complex bank holding companies of today are the best example of hybrid intermediaries, but I argue that financial firms from the "nonbank" space can just as easily evolve into conglomerates with similar organizational structure, thus acquiring the cap...

  2. Hybrid composites

    CSIR Research Space (South Africa)

    Jacob John, Maya

    2009-04-01

    Full Text Available effect was observed for the elongation at break of the hybrid composites. The impact strength of the hybrid composites increased with the addition of glass fibres. The tensile and impact properties of thermoplastic natural rubber reinforced short... panels made from conventional structural materials. Figure 3 illustrates the performance of cellular biocomposite panels against conventional systems used for building and residential construction, namely a pre- cast pre-stressed hollow core concrete...

  3. Method for producing a tube

    Science.gov (United States)

    Peterson, Kenneth A.; Rohde, Steven B.; Pfeifer, Kent B.; Turner, Timothy S.

    2007-01-02

    A method is described for producing tubular substrates having parallel spaced concentric rings of electrical conductors that can be used as the drift tube of an Ion Mobility Spectrometer (IMS). The invention comprises providing electrodes on the inside of a tube that are electrically connected to the outside of the tube through conductors that extend between adjacent plies of substrate that are combined to form the tube. Tubular substrates are formed from flexible polymeric printed wiring board materials, ceramic materials and material compositions of glass and ceramic, commonly known as Low Temperature Co-Fired Ceramic (LTCC). The adjacent plies are sealed together around the electrode.

  4. YouTube and 'psychiatry'.

    Science.gov (United States)

    Gordon, Robert; Miller, John; Collins, Noel

    2015-12-01

    YouTube is a video-sharing website that is increasingly used to share and disseminate health-related information, particularly among younger people. There are reports that social media sites, such as YouTube, are being used to communicate an anti-psychiatry message but this has never been confirmed in any published analysis of YouTube clip content. This descriptive study revealed that the representation of 'psychiatry' during summer 2012 was predominantly negative. A subsequent smaller re-analysis suggests that the negative portrayal of 'psychiatry' on YouTube is a stable phenomenon. The significance of this and how it could be addressed are discussed.

  5. Charm production in flux tubes

    CERN Document Server

    Aguiar, C E; Nazareth, R A M S; Pech, G

    1996-01-01

    We argue that the non-perturbative Schwinger mechanism may play an important role in the hadronic production of charm. We present a flux tube model which assumes that the colliding hadrons become color charged because of gluon exchange, and that a single non-elementary flux tube is built up as they recede. The strong chromoelectric field inside this tube creates quark pairs (including charmed ones) and the ensuing color screening breaks the tube into excited hadronic clusters. On their turn these clusters, or `fireballs', decay statistically into the final hadrons. The model is able to account for the soft production of charmed, strange and lighter hadrons within a unified framework.

  6. Charm production in flux tubes

    Science.gov (United States)

    Aguiar, C. E.; Kodama, T.; Nazareth, R. A. M. S.; Pech, G.

    1996-01-01

    We argue that the nonperturbative Schwinger mechanism may play an important role in the hadronic production of charm. We present a flux tube model which assumes that the colliding hadrons become color charged because of gluon exchange, and that a single nonelementary flux tube is built up as they recede. The strong chromoelectric field inside this tube creates quark pairs (including charmed ones) and the ensuing color screening breaks the tube into excited hadronic clusters. In their turn these clusters, or ``fireballs,'' decay statistically into the final hadrons. The model is able to account for the soft production of charmed, strange, and lighter hadrons within a unified framework.

  7. Effect of the sequence of tube rolling in a tube bundle of a shell and tube heat exchanger on the stress-deformed state of the tube sheet

    Science.gov (United States)

    Tselishchev, M. F.; Plotnikov, P. N.; Brodov, Yu. M.

    2015-11-01

    Rolling the tube sheet of a heat exchanger with U-shaped tubes, as exemplified by the vapor cooler GP-24, was simulated. The simulation was performed using the finite element method with account of elas- tic-plastic properties of the tube and tube sheet materials. The simulation consisted of two stages; at the first stage, maximum and residual contact stress in the conjunction of a separate tube and the tube sheet was determined using the "equivalent sleeve" model; at the second stage, the obtained contact stress was applied to the hole surface in the tube sheet. Thus, different tube rolling sequences were simulated: from the center to the periphery of the tube sheet and from the periphery to the center along a spiral line. The studies showed that the tube rolling sequence noticeably influences the value of the tube sheet residual deflection for the same rolling parameters of separate tubes. Residual deflection of the tube sheet in different planes was determined. It was established that the smallest residual deflection corresponds to the tube rolling sequence from the periphery to the center of the tube sheet. The following dependences were obtained for different rolling sequences: maximum deformation of the tube sheet as a function of the number of rolled tubes, residual deformation of the tube sheet along its surface, and residual deflection of the tube sheet as a function of the rotation angle at the periphery. The preferred sequence of tube rolling for minimizing the tube sheet deformation is indicated.

  8. Infrared imaging of LED lighting tubes and fluorescent tubes

    Science.gov (United States)

    Siikanen, Sami; Kivi, Sini; Kauppinen, Timo; Juuti, Mikko

    2011-05-01

    The low energy efficiency of conventional light sources is mainly caused by generation of waste heat. We used infrared (IR) imaging in order to monitor the heating of both LED tube luminaires and ordinary T8 fluorescent tubes. The IR images showed clearly how the surface temperatures of the fluorescent tube ends quickly rose up to about +50...+70°C, whereas the highest surface temperatures seen on the LED tubes were only about +30...+40°C. The IR images demonstrated how the heat produced by the individual LED chips can be efficiently guided to the supporting structure in order to keep the LED emitters cool and hence maintain efficient operation. The consumed electrical power and produced illuminance were also recorded during 24 hour measurements. In order to assess the total luminous efficacy of the luminaires, separate luminous flux measurements were made in a large integrating sphere. The currently available LED tubes showed efficacies of up to 88 lm/W, whereas a standard "cool white" T8 fluorescent tube produced ca. 75 lm/W. Both lamp types gave ca. 110 - 130 lx right below the ceiling-mounted luminaire, but the LED tubes consume only 40 - 55% of the electric power compared to fluorescent tubes.

  9. A virtual reality based simulator for learning nasogastric tube placement.

    Science.gov (United States)

    Choi, Kup-Sze; He, Xuejian; Chiang, Vico Chung-Lim; Deng, Zhaohong

    2015-02-01

    Nasogastric tube (NGT) placement is a common clinical procedure where a plastic tube is inserted into the stomach through the nostril for feeding or drainage. However, the placement is a blind process in which the tube may be mistakenly inserted into other locations, leading to unexpected complications or fatal incidents. The placement techniques are conventionally acquired by practising on unrealistic rubber mannequins or on humans. In this paper, a virtual reality based training simulation system is proposed to facilitate the training of NGT placement. It focuses on the simulation of tube insertion and the rendering of the feedback forces with a haptic device. A hybrid force model is developed to compute the forces analytically or numerically under different conditions, including the situations when the patient is swallowing or when the tube is buckled at the nostril. To ensure real-time interactive simulations, an offline simulation approach is adopted to obtain the relationship between the insertion depth and insertion force using a non-linear finite element method. The offline dataset is then used to generate real-time feedback forces by interpolation. The virtual training process is logged quantitatively with metrics that can be used for assessing objective performance and tracking progress. The system has been evaluated by nursing professionals. They found that the haptic feeling produced by the simulated forces is similar to their experience during real NGT insertion. The proposed system provides a new educational tool to enhance conventional training in NGT placement.

  10. Explosive welding of a tube into a tube sheet

    Energy Technology Data Exchange (ETDEWEB)

    Green, Sheryll C. (London, OH); Linse, Vonne D. (Columbus, OH)

    1978-10-03

    A cartridge containing an explosive charge is placed within a tube assembled within a tube sheet. The charge is detonated through use of a detonator cord containing a minimum but effective amount of explosive material. The cord is contained inside a tubular shield throughout most of its length within the cartridge. A small length of the cord extends beyond the tubular shield to contact and detonate the explosive charge in its rear portion near the cartridge base. The cartridge base is provided of substantial mass and thickness in respect to side and front walls of the cartridge to minimize bulging beyond the rear face of the tube sheet. For remote activation an electrically activated detonator of higher charge density than the cord is attached to the cord at a location spaced from the tube sheet, cartridge and tube.

  11. Explosive welding of a tube into a tube sheet

    Energy Technology Data Exchange (ETDEWEB)

    Green, S.C.; Linse, V.D.

    1978-10-03

    A cartridge containing an explosive charge is placed within a tube assembled within a tube sheet. The charge is detonated through use of a detonator cord containing a minimum but effective amount of explosive material. The cord is contained inside a tubular shield throughout most of its length within the cartridge. A small length of the cord extends beyond the tublar shield to contact and detonate the explosive charge in its rear portion near the cartridge base. The cartridge base is provided of substantial mass and thickness in respect to side and front walls of the cartridge to minimize bulging beyond the rear face of the tube sheet. For remote activation an electrically activated detonator of higher charge density than the cord is attached to the cord at a location spaced from the tube sheet, cartridge and tube.

  12. Nasogastric tube syndrome induced by an indwelling long intestinal tube.

    Science.gov (United States)

    Sano, Naoki; Yamamoto, Masayoshi; Nagai, Kentaro; Yamada, Keiichi; Ohkohchi, Nobuhiro

    2016-04-21

    The nasogastric tube (NGT) has become a frequently used device to alleviate gastrointestinal symptoms. Nasogastric tube syndrome (NTS) is an uncommon but potentially life-threatening complication of an indwelling NGT. NTS is characterized by acute upper airway obstruction due to bilateral vocal cord paralysis. We report a case of a 76-year-old man with NTS, induced by an indwelling long intestinal tube. He was admitted to our hospital for treatment of sigmoid colon cancer. He underwent sigmoidectomy to release a bowel obstruction, and had a long intestinal tube inserted to decompress the intestinal tract. He presented acute dyspnea following prolonged intestinal intubation, and bronchoscopy showed bilateral vocal cord paralysis. The NGT was removed immediately, and tracheotomy was performed. The patient was finally discharged in a fully recovered state. NTS be considered in patients complaining of acute upper airway obstruction, not only with a NGT inserted but also with a long intestinal tube.

  13. The influence of fiber orientation angle on the impact characteristic of circular aluminum tube reinforced by fiber glass/polyester

    Directory of Open Access Journals (Sweden)

    Kiatipong Komlungkang

    2015-03-01

    Full Text Available This study was aimed to increase the impact resistance of circular tubes reinforced by fiber reinforced plastic (FRP.The tube made of aluminum 6063-T5 with the D/t ratio of 25.40, 29.63, and 42.33. Outside surface of aluminum tube was reinforced by wrapping fiberglass/polyester. The fiber orientation angle were [0]3 , [45]3 , [90]3 , [0/902 ], [45/-452 ], and [90/02 ]. Then, they were tested under impact with cross head of 45 kg and speed of 6.26 m/s in axial direction. The result revealed that the impact resistance of the hybrid tube and aluminum tube trend to increase as the D/t ratio increases and The hybrid tube with wrapped angle of [0/902 ] was maximum mean load and higher than aluminum tube by 50.02, 45.14, and 52.03 % at D/t = 25.40, 29.63, and 42.33 receptively. Failure mode and crush behavior of hybrid tube were also presented and disused in this paper.

  14. Piezoelectric Rotary Tube Motor

    Science.gov (United States)

    Fisher, Charles D.; Badescu, Mircea; Braun, David F.; Culhane, Robert

    2011-01-01

    A custom rotary SQUIGGLE(Registered TradeMark) motor has been developed that sets new benchmarks for small motor size, high position resolution, and high torque without gear reduction. Its capabilities cannot be achieved with conventional electromagnetic motors. It consists of piezoelectric plates mounted on a square flexible tube. The plates are actuated via voltage waveforms 90 out of phase at the resonant frequency of the device to create rotary motion. The motors were incorporated into a two-axis postioner that was designed for fiber-fed spectroscopy for ground-based and space-based projects. The positioner enables large-scale celestial object surveys to take place in a practical amount of time.

  15. Primary Fallopian Tube Carcinoma

    Directory of Open Access Journals (Sweden)

    Prasad K Shetty

    2011-01-01

    Full Text Available Primary Fallopian Tube Carcinoma (PFTC is rare and accounts for about 0.3% of all gynecologic cancers. Less than 1500 cases have been reported in the literature. It arises in postmenopausal women and typically presents with abdominal pelvic pain, vaginal bleeding and watery discharge. However, a correct diagnosis is rarely achieved preoperative, and in many cases, the diagnosis is made after incidental surgery for unrelated conditions commonly being ovarian carcinoma . Compared with ovarian carcinoma, PFTC more often presents at early stages, but it has a worse prognosis. PFTC is usually managed in the same manner as ovarian cancer. We report a case of Left PFTC that presented as Left ovarian mass, and we briefly review the literature.

  16. Performance of a SensL-30035-16P Silicon Photomultiplier array at liquid argon temperature

    CERN Document Server

    Catalanotti, S; Covone, G; Incecco, M D; Fiorillo, G; Korga, G; Rossi, B; Walker, S

    2015-01-01

    Next generation multi-ton scale noble liquid experiments have the unique opportunity to discover dark matter particles at the TeV scale, reaching the sensitivity of 10^-48 cm2 in the WIMP nucleon scattering cross-section. A prerequisite will be the reduction of radiogenic background sources to negligible levels. This is only possible if ultra pure high efficiency photosensors are available for the scintillation light readout. Current experiments (e.g. Xenon, LUX, Darkside, ArDM) use cryogenic PMTs as photosensors. An attractive alternative is represented by silicon photomultiplier arrays (SiPM arrays), which show unrivalled performances in single photon detection. This paper reports on the performance of the SensL-30035-16P SiPM array and a custom made cryogenic front-end board at the liquid argon temperature.

  17. MuTRiG: a mixed signal Silicon Photomultiplier readout ASIC with high timing resolution and gigabit data link

    Science.gov (United States)

    Chen, H.; Briggl, K.; Eckert, P.; Harion, T.; Munwes, Y.; Shen, W.; Stankova, V.; Schultz-Coulon, H. C.

    2017-01-01

    MuTRiG is a mixed signal Silicon Photomultiplier readout ASIC designed in UMC 180 nm CMOS technology for precise timing and high event rate applications in high energy physics experiments and medical imaging. It is dedicated to the readout of the scintillating fiber detector and the scintillating tile detector of the Mu3e experiment. The MuTRiG chip extends the excellent timing performance of the STiCv3 chip with a fast digital readout for high rate applications. The high timing performance of the fully differential SiPM readout channels and 50 ps time binning TDCs are complemented by an upgraded digital readout logic and a 1.28 Gbps LVDS serial data link. The design of the chip and the characterization results of the analog front-end, TDC and the LVDS data link are presented.

  18. Characterization of the first prototypes of Silicon Photomultipliers with bulk-integrated quench resistor fabricated at MPI semiconductor laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Jendrysik, Christian, E-mail: jendrysik@hll.mpg.de [Max-Planck-Institut Halbleiterlabor, Otto-Hahn-Ring 6, D-81739 Munich (Germany); Max-Planck-Institut für Physik, Föhringer Ring 6, D-80805 Munich (Germany); Andriček, Ladislav; Liemann, Gerhard; Moser, Hans-Günther; Ninković, Jelena; Richter, Rainer [Max-Planck-Institut Halbleiterlabor, Otto-Hahn-Ring 6, D-81739 Munich (Germany); Max-Planck-Institut für Physik, Föhringer Ring 6, D-80805 Munich (Germany); Schopper, Florian [Max-Planck-Institut Halbleiterlabor, Otto-Hahn-Ring 6, D-81739 Munich (Germany); Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße, D-85748 Garching (Germany)

    2013-08-01

    In this paper new results of the characterization of Silicon Photomultipliers (SiPMs) with bulk-integrated quench resistor will be presented. The novel detector concept was developed at the Max-Planck-Institute (MPI) semiconductor laboratory and allows a metal and polysilicon free entrance window which offers an improvement in photon detection efficiency (PDE). For electrical separation and suppression of optical cross talk (OCT) an insensitive area (gap) between neighboring cells is required. Based on simulations the first prototypes with devices of different combinations of cell size and gap were fabricated, providing the opportunity to study the influence of these parameters on the detector performance. First PDE measurements of the new detector are presented together with results of the influence of geometrical variations. Also an outlook on possible future developments of the concept with single cell read-out is given.

  19. Flaming on YouTube

    NARCIS (Netherlands)

    Moor, Peter J.; Heuvelman, A.; Verleur, R.

    2010-01-01

    In this explorative study, flaming on YouTube was studied using surveys of YouTube users. Flaming is defined as displaying hostility by insulting, swearing or using otherwise offensive language. Three general conclusions were drawn. First, although many users said that they themselves do not flame,

  20. Interpreting Shock Tube Ignition Data

    Science.gov (United States)

    2003-10-01

    times only for high concentrations (of order 1% fuel or greater). The requirements of engine (IC, HCCI , CI and SI) modelers also present a different...Paper 03F-61 Interpreting Shock Tube Ignition Data D. F. Davidson and R. K. Hanson Mechanical Engineering ... Engineering Department Stanford University, Stanford CA 94305 Abstract Chemical kinetic modelers make extensive use of shock tube ignition data

  1. Flaming on YouTube

    NARCIS (Netherlands)

    Moor, Peter J.; Heuvelman, Ard; Verleur, Ria

    2010-01-01

    In this explorative study, flaming on YouTube was studied using surveys of YouTube users. Flaming is defined as displaying hostility by insulting, swearing or using otherwise offensive language. Three general conclusions were drawn. First, although many users said that they themselves do not flame,

  2. Transfer function of protoplasmic tubes of Physarum polycephalum.

    Science.gov (United States)

    Whiting, James G H; de Lacy Costello, Ben P J; Adamatzky, Andrew

    2015-02-01

    The slime mould Physarum polycephalum is a large single celled myxomycete; its plasmodium consists of tubes which extend to find sources of food. It has been previously shown that the tubes are conductive with a resistance of approximately 3 MΩ, and have been used in basic DC circuits. Hybrid slime mould-electronic circuits have been proposed, using the protoplasmic tubes, grown between agar, as Physarum wires. This paper aims to evaluate the electrical properties of the protoplasmic tubes with respect to analogue and digital waveforms. The Physarum wires act as low pass filters with a mean cut off frequency of 19kHz (SD 9 KHz); they have a 12.1 dB/decade roll-off (SD 1.9 dB/decade). Mean attenuation across the band-pass range is -6 dB (S.D. 4.5 dB). The mechanism for the frequency dependant attenuation is unknown however a combination of protoplasmic electrolyte and the cytoskeletal structure is the most likely cause. The tubes last approximately 2 weeks before forming a dry sclerotia, when they cease being conductive and is the prevalent limiting factor of their practical use; this is caused by dehydration and lack of nutrition, a limitation which may be overcome. The potential for Physarum wires in hybrid circuits is strengthened; while previous circuits were simple DC circuits, this work demonstrates that they may be used as electronic components or wires in both digital and analogue circuits or even as a computing component in analogue computers. Copyright © 2015. Published by Elsevier Ireland Ltd.

  3. Water-storage-tube systems. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hemker, P.

    1981-12-24

    Passive solar collection/storage/distribution systems were surveyed, designed, fabricated, and mechanically and thermally tested. The types studied were clear and opaque fiberglass tubes, metal tubes with plastic liners, and thermosyphoning tubes. (MHR)

  4. Vidicon storage tube electrical input/output

    Science.gov (United States)

    Lipoma, P.

    1972-01-01

    Electrical data storage tube is assembled from standard vidicon tube using conventional amplification and control circuits. Vidicon storage tube is simple, inexpensive and has an erase and preparation time of less than 5 microseconds.

  5. Very low power, high voltage base for a Photo Multiplier Tube for the KM3NeT deep sea neutrino telescope

    CERN Document Server

    Timmer, P; Peek, H

    2010-01-01

    The described system is developed in the framework of a deep-sea submerged Very Large Volume neutrino Telescope where photons are detected by a large number of Photo Multiplier Tubes. These PMTs are placed in optical modules (OM). A basic Cockcroft-Walton (CW) voltage multiplier circuit design is used to generate multiple voltages to drive the dynodes of the photomultiplier tube. To achieve a long lifetime and a high reliability the dissipation in the OM must be kept to the minimum. The design is also constrained by size restrictions, load current, voltage range, and the maximum allowable ripple in the output voltage. A surface mount PMT-base PCB prototype is designed and successfully tested. The system draws less than 1.5 mA of supply current at a voltage of 3.3 V with outputs up to -1400 Vdc cathode voltage, a factor 10 less than the commercially available state of the art

  6. Acoustical studies on corrugated tubes

    Science.gov (United States)

    Balaguru, Rajavel

    Corrugated tubes and pipes offer greater global flexibility combined with local rigidity. They are used in numerous engineering applications such as vacuum cleaner hosing, air conditioning systems of aircraft and automobiles, HVAC control systems of heating ducts in buildings, compact heat exchangers, medical equipment and offshore gas and oil transportation flexible riser pipelines. Recently there has been a renewed research interest in analyzing the flow through a corrugated tube to understand the underlying mechanism of so called whistling, although the whistling in such a tube was identified in early twentieth century. The phenomenon of whistling in a corrugated tube is interesting because an airflow through a smooth walled tube of similar dimensions will not generate any whistling tones. Study of whistling in corrugated tubes is important because, it not only causes an undesirable noise problem but also results in flow-acoustic coupling. Such a coupling can cause significant structural vibrations due to flow-acoustic-structure interaction. This interaction would cause flow-induced vibrations that could result in severe damage to mechanical systems having corrugated tubes. In this research work, sound generation (whistling) in corrugated tubes due to airflow is analyzed using experimental as well as Computational Fluid Dynamics-Large Eddy Simulation (CFD-LES) techniques. Sound generation mechanisms resulting in whistling have been investigated. The whistling in terms of frequencies and sound pressure levels for different flow velocities are studied. The analytical and experimental studies are carried out to understand the influence of various parameters of corrugated tubes such as cavity length, cavity width, cavity depth, pitch, Reynolds numbers and number of corrugations. The results indicate that there is a good agreement between theoretically calculated, computationally predicted and experimentally measured whistling frequencies and sound pressure levels

  7. Electronic components, tubes and transistors

    CERN Document Server

    Dummer, G W A

    1965-01-01

    Electronic Components, Tubes and Transistors aims to bridge the gap between the basic measurement theory of resistance, capacitance, and inductance and the practical application of electronic components in equipments. The more practical or usage aspect of electron tubes and semiconductors is given emphasis over theory. The essential characteristics of each main type of component, tube, and transistor are summarized. This book is comprised of six chapters and begins with a discussion on the essential characteristics in terms of the parameters usually required in choosing a resistor, including s

  8. PEG tubes: dealing with complications.

    Science.gov (United States)

    Malhi, Hardip; Thompson, Rosie

    A percutaneous endoscopic gastronomy tube can be used to deliver nutrition, hydration and medicines directly into the patient's stomach. Patients will require a tube if they are unable to swallow safely, putting them at risk of aspiration of food, drink and medicines into their lungs. It is vital that nurses are aware of the complications that may arise when caring for a patient with a PEG tube. It is equally important that nurses know how to deal with these complications or from where tc seek advice. This article provides a quick troubleshooting guide to help nurses deal with complications that can arise with PEG feeding.

  9. Hybrid Pixel Detectors for gamma/X-ray imaging

    Science.gov (United States)

    Hatzistratis, D.; Theodoratos, G.; Zografos, V.; Kazas, I.; Loukas, D.; Lambropoulos, C. P.

    2015-09-01

    Hybrid pixel detectors are made by direct converting high-Z semi-insulating single crystalline material coupled to complementary-metal-oxide semiconductor (CMOS) readout electronics. They are attractive because direct conversion exterminates all the problems of spatial localization related to light diffusion, energy resolution, is far superior from the combination of scintillation crystals and photomultipliers and lithography can be used to pattern electrodes with very fine pitch. We are developing 2-D pixel CMOS ASICs, connect them to pixilated CdTe crystals with the flip chip and bump bonding method and characterize the hybrids. We have designed a series of circuits, whose latest member consists of a 50×25 pixel array with 400um pitch and an embedded controller. In every pixel a full spectroscopic channel with time tagging information has been implemented. The detectors are targeting Compton scatter imaging and they can be used for coded aperture imaging too. Hybridization using CMOS can overcome the limit put on pixel circuit complexity by the use of thin film transistors (TFT) in large flat panels. Hybrid active pixel sensors are used in dental imaging and other applications (e.g. industrial CT etc.). Thus X-ray imaging can benefit from the work done on dynamic range enhancement methods developed initially for visible and infrared CMOS pixel sensors. A 2-D CMOS ASIC with 100um pixel pitch to demonstrate the feasibility of such methods in the context of X-ray imaging has been designed.

  10. LHCb: Quantum Efficiency of Hybrid Photon Detectors for the LHCb RICH

    CERN Multimedia

    Lambert, Robert W

    2007-01-01

    The production of 550 hybrid photon detectors to be used within the LHCb RICH detectors has recently finished. Photonis-DEP have succeeded in consistently improving the tube quantum efficiency, by a relative 27,% with respect to preseries and prototype tubes, when integrated over the energy spectrum.

  11. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... questions Clinical Studies Publications Catalog Photos and Images Spanish Language Information Dilated Exam Grants and Funding Extramural ... Low Vision Refractive Errors Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded video ...

  12. Tube-wave seismic imaging

    Science.gov (United States)

    Korneev, Valeri A [LaFayette, CA

    2009-05-05

    The detailed analysis of cross well seismic data for a gas reservoir in Texas revealed two newly detected seismic wave effects, recorded approximately 2000 feet above the reservoir. A tube-wave (150) is initiated in a source well (110) by a source (111), travels in the source well (110), is coupled to a geological feature (140), propagates (151) through the geological feature (140), is coupled back to a tube-wave (152) at a receiver well (120), and is and received by receiver(s) (121) in either the same (110) or a different receiving well (120). The tube-wave has been shown to be extremely sensitive to changes in reservoir characteristics. Tube-waves appear to couple most effectively to reservoirs where the well casing is perforated, allowing direct fluid contact from the interior of a well case to the reservoir.

  13. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... questions Clinical Studies Publications Catalog Photos and Images Spanish Language Information Grants and Funding Extramural Research Division ... Low Vision Refractive Errors Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded video ...

  14. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... Grants and Funding Extramural Research Division of Extramural Science Programs Division of Extramural Activities Extramural Contacts NEI ... Amaurosis Low Vision Refractive Errors Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded ...

  15. Pulse tube refrigerator; Parusukan reitoki

    Energy Technology Data Exchange (ETDEWEB)

    Hozumi, Yoshikazu [University of Tsukuba, Tsukuba (Japan); Shiraishi, Masao [Hiroshima University, Hiroshima (Japan)

    1999-06-05

    In the cryogenic field, high temperature superconductivity and research and development of the peripheral technology are popular. Refrigerating machine development of the very low temperature is also one of the results. Research and development are mainly advanced as a refrigerating machine of the center for the aerospace plane installation. There is special and small very low temperature refrigerating machine called 'the pulse tube refrigerating machine' of which the practical application is also recently being attempted for the semiconductor cooling using high temperature superconductivity. At present, the basic research of elucidation of refrigeration phenomenon of pulse tube refrigerating machine and development of high-performance pulse tube refrigerating machine is carried out by experiment in the Ministry of International Trade and Industry Mechanical Engineering Lab., Agency of Industrial Sci. and Technology and numerical simulation in Chiyoda Corp. In this report, the pulse tube refrigerating machine is introduced, and the application in the chemical engineering field is considered. (NEDO)

  16. Lunar Core Drive Tubes Summary

    Data.gov (United States)

    National Aeronautics and Space Administration — Contains a brief summary and high resolution imagery from various lunar rock and core drive tubes collected from the Apollo and Luna missions to the moon.

  17. Tube wall thickness measurement apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Lagasse, P.R.

    1987-01-06

    An apparatus is described for measuring the thickness of a tube's wall for the tube's entire length and circumference by determining the deviation of the tube wall thickness from the known thickness of a selected standard item, the apparatus comprising: a. a base; b. a first support member having first and second ends, the first end being connected to the base, the first support member having a sufficiently small circumference that the tube can be slid over the first support member; c. a spherical element, the spherical element being connected to the second end of the first support member. The spherical element has a sufficiently small circumference at its equator that the tube can be slid over the spherical element, the spherical element having at its equator a larger circumference than the first support member; d. a second support member having first and second ends, the first end being connected to the base, the second support member being spaced apart form the first support member; e. a positioning element connected to and moveable relative to the second support member; and f. an indicator connected to the positioning element and being moveable thereby to a location proximate the spherical element. The indicator includes a contact ball for contacting the selected standard item and holding it against the spherical element, the contact ball contacting the tube when the tube is disposed about the spherical element. The indicator includes a dial having a rotatable needle for indicating the deviation of the tube wall thickness from the thickness of the selected standard item, the rotatable needle being operatively connected to and responsive to the position of the contact ball.

  18. Studies of a Next-Generation Silicon-Photomultiplier-Based Time-of-Flight PET/CT System.

    Science.gov (United States)

    Hsu, David F C; Ilan, Ezgi; Peterson, William T; Uribe, Jorge; Lubberink, Mark; Levin, Craig S

    2017-09-01

    This article presents system performance studies for the Discovery MI PET/CT system, a new time-of-flight system based on silicon photomultipliers. System performance and clinical imaging were compared between this next-generation system and other commercially available PET/CT and PET/MR systems, as well as between different reconstruction algorithms. Methods: Spatial resolution, sensitivity, noise-equivalent counting rate, scatter fraction, counting rate accuracy, and image quality were characterized with the National Electrical Manufacturers Association NU-2 2012 standards. Energy resolution and coincidence time resolution were measured. Tests were conducted independently on two Discovery MI scanners installed at Stanford University and Uppsala University, and the results were averaged. Back-to-back patient scans were also performed between the Discovery MI, Discovery 690 PET/CT, and SIGNA PET/MR systems. Clinical images were reconstructed using both ordered-subset expectation maximization and Q.Clear (block-sequential regularized expectation maximization with point-spread function modeling) and were examined qualitatively. Results: The averaged full widths at half maximum (FWHMs) of the radial/tangential/axial spatial resolution reconstructed with filtered backprojection at 1, 10, and 20 cm from the system center were, respectively, 4.10/4.19/4.48 mm, 5.47/4.49/6.01 mm, and 7.53/4.90/6.10 mm. The averaged sensitivity was 13.7 cps/kBq at the center of the field of view. The averaged peak noise-equivalent counting rate was 193.4 kcps at 21.9 kBq/mL, with a scatter fraction of 40.6%. The averaged contrast recovery coefficients for the image-quality phantom were 53.7, 64.0, 73.1, 82.7, 86.8, and 90.7 for the 10-, 13-, 17-, 22-, 28-, and 37-mm-diameter spheres, respectively. The average photopeak energy resolution was 9.40% FWHM, and the average coincidence time resolution was 375.4 ps FWHM. Clinical image comparisons between the PET/CT systems demonstrated the high

  19. Tube wall thickness measurement apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Lagasse, P.R.

    1985-06-21

    An apparatus for measuring the thickness of a tube's wall for the tube's entire length and radius by determining the deviation of the tube wall thickness from the known thickness of a selected standard item. The apparatus comprises a base and a first support member having first and second ends. The first end is connected to the base and the second end is connected to a spherical element. A second support member is connected to the base and spaced apart from the first support member. A positioning element is connected to and movable relative to the second support member. An indicator is connected to the positioning element and is movable to a location proximate the spherical element. The indicator includes a contact ball for first contacting the selected standard item and holding it against the spherical element. The contact ball then contacts the tube when the tube is disposed about the spherical element. The indicator includes a dial having a rotatable needle for indicating the deviation of the tube wall thickness from the thickness of the selected standard item.

  20. Tube wall thickness measurement apparatus

    Science.gov (United States)

    Lagasse, P.R.

    1985-06-21

    An apparatus for measuring the thickness of a tube's wall for the tube's entire length and radius by determining the deviation of the tube wall thickness from the known thickness of a selected standard item. The apparatus comprises a base and a first support member having first and second ends. The first end is connected to the base and the second end is connected to a spherical element. A second support member is connected to the base and spaced apart from the first support member. A positioning element is connected to and movable relative to the second support member. An indicator is connected to the positioning element and is movable to a location proximate the spherical element. The indicator includes a contact ball for first contacting the selected standard item and holding it against the spherical element. The contact ball then contacts the tube when the tube is disposed about the spherical element. The indicator includes a dial having a rotatable needle for indicating the deviation of the tube wall thickness from the thickness of the selected standard item.