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Silicon detector

M Nocente, D Rigamonti, V Perseo, M Tardocchi, G Boltruczyk, A Broslawski, A Cremona, G Croci, M Gosk, V Kiptily, S Korolczuk, M Mazzocco, A Muraro, E Strano, I Zychor, G Gorini
Gamma-ray spectroscopy measurements at MHz counting rates have been carried out, for the first time, with a compact spectrometer based on a LaBr3 scintillator and silicon photomultipliers. The instrument, which is also insensitive to magnetic fields, has been developed in view of the upgrade of the gamma-ray camera diagnostic for α particle measurements in deuterium-tritium plasmas of the Joint European Torus. Spectra were measured up to 2.9 MHz with a projected energy resolution of 3%-4% in the 3-5 MeV range, of interest for fast ion physics studies in fusion plasmas...
November 2016: Review of Scientific Instruments
E Pasch, M N A Beurskens, S A Bozhenkov, G Fuchert, J Knauer, R C Wolf
This paper describes the design of the Thomson scattering system at the Wendelstein 7-X stellarator. For the first operation campaign we installed a 10 spatial channel system to cover a radial half profile of the plasma cross section. The start-up system is based on one Nd:YAG laser with 10 Hz repetition frequency, one observation optics, five fiber bundles with one delay line each, and five interference filter polychromators with five spectral channels and silicon avalanche diodes as detectors. High dynamic range analog to digital converters with 14 bit, 1 GS/s are used to digitize the signals...
November 2016: Review of Scientific Instruments
A Netepenko, W U Boeglin, D S Darrow, R Ellis, M J Sibilia
Detection of charged fusion products, such as protons and tritons resulting from D(d, p) t reactions, can be used to determine the position and time dependent fusion reaction rate profile in spherical tokamak plasmas with neutral beam heating. We have developed a prototype instrument consisting of 6 ion-implanted-silicon surface barrier detectors combined with collimators in such a way that each detector can accept 3 MeV protons and 1 MeV tritons and thus provides a curved view across the plasma cross section...
November 2016: Review of Scientific Instruments
L Nozka, L Adamczyk, G Avoni, A Brandt, P Buglewicz, E Cavallaro, G Chiodini, L Chytka, K Ciesla, P M Davis, M Dyndal, S Grinstein, P Hamal, M Hrabovsky, K Janas, K Jirakova, M Kocian, T Komarek, K Korcyl, J Lange, D Mandat, V Michalek, I Lopez Paz, D Northacker, M Rijssenbeek, L Seabra, P Schovanek, R Staszewski, P Swierska, T Sykora
We present the construction of the optical part of the ToF (time-of-flight) subdetector prototype for the AFP (ATLAS Forward Proton) detector. The ToF detector in conjunction with a 3D silicon pixel tracker will tag and measure protons originating in central exclusive interactions p + p → p + X + p, where the two outgoing protons are scattered in the very forward directions. The ToF is required to reduce so-called pileup backgrounds that arise from multiple proton interactions in the same bunch crossing at high luminosity...
November 28, 2016: Optics Express
Risheng Cheng, Xiang Guo, Xiaosong Ma, Linran Fan, King Y Fong, Menno Poot, Hong X Tang
We describe a micromachining process to allow back-side coupling of an array of single-mode telecommunication fibers to individual superconducting nanowire single photon detectors (SNSPDs). This approach enables a back-illuminated detector structure which separates the optical access and electrical readout on two sides of the chip and thus allows for compact integration of multi-channel detectors. As proof of principle, we show the integration of four detectors on the same silicon chip with two different designs and their performances are compared...
November 28, 2016: Optics Express
Danial Chitnis, Robert J Cooper, Laura Dempsey, Samuel Powell, Simone Quaggia, David Highton, Clare Elwell, Jeremy C Hebden, Nicholas L Everdell
We present the first three-dimensional, functional images of the human brain to be obtained using a fibre-less, high-density diffuse optical tomography system. Our technology consists of independent, miniaturized, silicone-encapsulated DOT modules that can be placed directly on the scalp. Four of these modules were arranged to provide up to 128, dual-wavelength measurement channels over a scalp area of approximately 60 × 65 mm(2). Using a series of motor-cortex stimulation experiments, we demonstrate that this system can obtain high-quality, continuous-wave measurements at source-detector separations ranging from 14 to 55 mm in adults, in the presence of hair...
October 1, 2016: Biomedical Optics Express
John Lehman, Andreas Steiger, Nathan Tomlin, Malcolm White, Mathias Kehrt, Ivan Ryger, Michelle Stephens, Christian Monte, Ingmar Mueller, Joerg Hollandt, Marla Dowell
The absolute responsivity of a planar cryogenic radiometer fabricated from micromachined silicon and having carbon nanotubes, as the absorber and thermistor were measured in the visible and far infrared (free-field terahertz) wavelength range by means of detector-based radiometry. The temperature coefficient of the thermistor near 4.8 K and noise equivalent power were evaluated along with independent characterization of the window transmittance and specular reflectance of the nanotube absorber. Measurements of absolute power by means of electrical substitution are compared to the German national standard and the uncertainty of the radiometer responsivity as a function of wavelength is summarized...
November 14, 2016: Optics Express
Carey E Donald, Richard P Scott, Kathy L Blaustein, Mary L Halbleib, Makhfousse Sarr, Paul C Jepson, Kim A Anderson
We detected between 2 and 10 pesticides per person with novel sampling devices worn by 35 participants who were actively engaged in farming in Diender, Senegal. Participants were recruited to wear silicone wristbands for each of two separate periods of up to 5 days. Pesticide exposure profiles were highly individualized with only limited associations with demographic data. Using a 63-pesticide dual-column gas chromatography-electron capture detector (GC-ECD) method, we detected pyrethoid insecticides most frequently, followed by organophosphate pesticides which have been linked to adverse health outcomes...
August 2016: Royal Society Open Science
Xianjun Ye, Matthew D McCluskey
In conventional confocal microscopy, a physical pinhole is placed at the image plane prior to the detector to limit the observation volume. In this work, we present a modular design of a scanning confocal microscope which uses a CCD camera to replace the physical pinhole for materials science applications. Experimental scans were performed on a microscope resolution target, a semiconductor chip carrier, and a piece of etched silicon wafer. The data collected by the CCD were processed to yield images of the specimen...
2016: PloS One
Mohammad Alavirad, Anthony Olivieri, Langis Roy, Pierre Berini
In this paper we present a sub-bandgap photodetector consisting of a metal grating on a thin metal patch on silicon, which makes use of the enhancement produced by the excitation of surface plasmon polaritons at the metal-silicon interface. The grating is defined via e-beam lithography and Au lift-off on a Au patch defined beforehand by optical lithography on doped p-type silicon. The surface plasmon polaritons are absorbed by the metal, leading to the creation of hot holes that can cross into the silicon where they are collected as the photocurrent...
October 3, 2016: Optics Express
M Morrocchi, W C J Hunter, A Del Guerra, T K Lewellen, P E Kinahan, L R MacDonald, M G Bisogni, R S Miyaoka
A PET detector featuring a pseudo-monolithic crystal is being developed as a more cost-effective alternative to a full monolithic crystal PET detector. This work evaluates different methods to localize the scintillation events in quartered monolithic crystals that are optically coupled. A semi-monolithic crystal assembly was formed using four 26  ×  26  ×  10 mm(3) LYSO crystals optically coupled together using optical adhesive, to mimic a 52  ×  52  ×  10 mm(3) monolithic crystal detector...
December 7, 2016: Physics in Medicine and Biology
J T Taylor, G Poludniowski, T Price, C Waltham, P P Allport, G L Casse, M Esposito, P M Evans, S Green, S Manger, S Manolopoulos, J Nieto-Camero, D J Parker, J Symons, N M Allinson
PURPOSE: Radiography and tomography using proton beams promise benefit to image guidance and treatment planning for proton therapy. A novel proton tracking detector is described and experimental demonstrations at a therapy facility are reported. A new type of proton CT reconstructing relative "scattering power" rather than "stopping power" is also demonstrated. Notably, this new type of imaging does not require the measurement of the residual energies of the protons. METHODS: A large area, silicon microstrip tracker with high spatial and temporal resolution has been developed by the Proton Radiotherapy Verification and Dosimetry Applications consortium and commissioned using beams of protons at iThemba LABS, Medical Radiation Department, South Africa...
November 2016: Medical Physics
Min-Young Lee, Bin Han, Cesare Jenkins, Lei Xing, Tae-Suk Suh
PURPOSE: The purpose of total body irradiation (TBI) techniques is to deliver a uniform radiation dose to the entire volume of a patient's body. Due to variations in the thickness of the patient, it is difficult to produce such a uniform dose distribution throughout the body. In many techniques, a compensator is used to adjust the dose delivered to various sections of the patient. The current study aims to develop and validate an innovative method of using depth-sensing cameras and 3D printing techniques for TBI treatment planning and compensator fabrication...
November 2016: Medical Physics
B Bassey, M Martinson, N Samadi, G Belev, C Karanfil, P Qi, D Chapman
A multiple energy imaging system that can extract multiple endogenous or induced contrast materials as well as water and bone images would be ideal for imaging of biological subjects. The continuous spectrum available from synchrotron light facilities provides a nearly perfect source for multiple energy x-ray imaging. A novel multiple energy x-ray imaging system, which prepares a horizontally focused polychromatic x-ray beam, has been developed at the BioMedical Imaging and Therapy bend magnet beamline at the Canadian Light Source...
November 2, 2016: Physics in Medicine and Biology
Petter Ström, Per Petersson, Marek Rubel, Göran Possnert
A dedicated detector system for heavy ion elastic recoil detection analysis at the Tandem Laboratory of Uppsala University is presented. Benefits of combining a time-of-flight measurement with a segmented anode gas ionization chamber are demonstrated. The capability of ion species identification is improved with the present system, compared to that obtained when using a single solid state silicon detector for the full ion energy signal. The system enables separation of light elements, up to Neon, based on atomic number while signals from heavy elements such as molybdenum and tungsten are separated based on mass, to a sample depth on the order of 1 μm...
October 2016: Review of Scientific Instruments
Danielle N Gurgew, David M Broadway, Mikhail Gubarev, Brian D Ramsey, Don A Gregory
An X-ray reflectometer (XRR) system has been developed at the Marshall Space Flight Center (MSFC) for characterizing various soft and hard X-ray optic coatings. The XRR instrument generates X-ray radiation using a high-output rotating anode source (RAS), operational over a voltage range of 5-35 kV and a current range of 10-150 mA. Copper is used as the target material to produce an X-ray spectrum from which the Kα line at 8.048 keV is isolated for the reflectivity measurements. Five precision slits are mounted along the X-ray beam path to limit the extent of the beam at the sample and to adjust the resolution in the measurements...
October 2016: Review of Scientific Instruments
Kento Terasaki, Toshioh Fujibuchi, Hiroo Murazaki, Taku Kuramoto, Yoshiyuki Umezu, Yang Ishigaki, Yoshinori Matsumoto
Real-time radiation dose management is important because staff members working in interventional radiology may be exposed to relatively high doses of primary and scattered radiation from the body of a patient. In this study, we investigated the dependence of energy and dose rate of the commercially available semiconductor detector named Pocket Geiger (POKEGA) for personal monitoring in diagnostic X-rays. In the energy-dependence study, a suitable metal filter and the threshold level were examined for energy compensation using a Monte Carlo calculation code...
October 28, 2016: Radiological Physics and Technology
Sebastian Cartier, Matias Kagias, Anna Bergamaschi, Zhentian Wang, Roberto Dinapoli, Aldo Mozzanica, Marco Ramilli, Bernd Schmitt, Martin Brückner, Erik Fröjdh, Dominic Greiffenberg, Davit Mayilyan, Davide Mezza, Sophie Redford, Christian Ruder, Lukas Schädler, Xintian Shi, Dhanya Thattil, Gemma Tinti, Jiaguo Zhang, Marco Stampanoni
MÖNCH is a 25 µm-pitch charge-integrating detector aimed at exploring the limits of current hybrid silicon detector technology. The small pixel size makes it ideal for high-resolution imaging. With an electronic noise of about 110 eV r.m.s., it opens new perspectives for many synchrotron applications where currently the detector is the limiting factor, e.g. inelastic X-ray scattering, Laue diffraction and soft X-ray or high-resolution color imaging. Due to the small pixel pitch, the charge cloud generated by absorbed X-rays is shared between neighboring pixels for most of the photons...
November 1, 2016: Journal of Synchrotron Radiation
Alexander Britz, Tadesse A Assefa, Andreas Galler, Wojciech Gawelda, Michael Diez, Peter Zalden, Dmitry Khakhulin, Bruno Fernandes, Patrick Gessler, Hamed Sotoudi Namin, Andreas Beckmann, Manuel Harder, Hasan Yavaş, Christian Bressler
The technical implementation of a multi-MHz data acquisition scheme for laser-X-ray pump-probe experiments with pulse limited temporal resolution (100 ps) is presented. Such techniques are very attractive to benefit from the high-repetition rates of X-ray pulses delivered from advanced synchrotron radiation sources. Exploiting a synchronized 3.9 MHz laser excitation source, experiments in 60-bunch mode (7.8 MHz) at beamline P01 of the PETRA III storage ring are performed. Hereby molecular systems in liquid solutions are excited by the pulsed laser source and the total X-ray fluorescence yield (TFY) from the sample is recorded using silicon avalanche photodiode detectors (APDs)...
November 1, 2016: Journal of Synchrotron Radiation
Martina Zangheri, Fabio Di Nardo, Mara Mirasoli, Laura Anfossi, Augusto Nascetti, Domenico Caputo, Giampiero De Cesare, Massimo Guardigli, Claudio Baggiani, Aldo Roda
A novel and disposable cartridge for chemiluminescent (CL)-lateral flow immunoassay (LFIA) with integrated amorphous silicon (a-Si:H) photosensors array was developed and applied to quantitatively detect human serum albumin (HSA) in urine samples. The presented analytical method is based on an indirect competitive immunoassay using horseradish peroxidase (HRP) as a tracer, which is detected by adding the luminol/enhancer/hydrogen peroxide CL cocktail. The system comprises an array of a-Si:H photosensors deposited on a glass substrate, on which a PDMS cartridge that houses the LFIA strip and the reagents necessary for the CL immunoassay was optically coupled to obtain an integrated analytical device controlled by a portable read-out electronics...
December 2016: Analytical and Bioanalytical Chemistry
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