WorldWideScience

Sample records for cherenkov imaging applications

  1. Cherenkov detectors for spatial imaging applications using discrete-energy photons

    Science.gov (United States)

    Rose, Paul B.; Erickson, Anna S.

    2016-08-01

    Cherenkov detectors can offer a significant advantage in spatial imaging applications when excellent timing response, low noise and cross talk, large area coverage, and the ability to operate in magnetic fields are required. We show that an array of Cherenkov detectors with crude energy resolution coupled with monochromatic photons resulting from a low-energy nuclear reaction can be used to produce a sharp image of material while providing large and inexpensive detector coverage. The analysis of the detector response to relative transmission of photons with various energies allows for reconstruction of material's effective atomic number further aiding in high-Z material identification.

  2. Large size SiPM matrix for Imaging Atmospheric Cherenkov Telescopes applications

    Science.gov (United States)

    Ambrosi, G.; Corti, D.; Ionica, M.; Manea, C.; Mariotti, M.; Rando, R.; Reichardt, I.; Schultz, C.

    2016-07-01

    SiPM photo detectors are nowadays commonly used in many applications. For large size telescopes like MAGIC or the future Large Size Telescope (LST) of the Cherenkov Telescope Array (CTA) project, a pixel size of some square centimeters is needed. An analog amplifier and sum stage was built and characterized. A large and compact SiPM matrix prototype, with the associated focusing optics, was assembled into a monolithic light detector with an active area of 3 cm2. The performance of the electronics is tailored for Imaging Atmospheric Cherenkov Telescopes (IACT) applications, with fast signal and adequate signal-to-noise (S/N) ratio.

  3. Cherenkov radiation fluence estimates in tissue for molecular imaging and therapy applications

    Science.gov (United States)

    Glaser, Adam K.; Zhang, Rongxiao; Andreozzi, Jacqueline; Gladstone, David; Pogue, Brian

    2016-03-01

    Cherenkov radiation has emerged as a novel source of light with a number of applications in the biomedical sciences. It's unique properties, including its broadband emission spectrum, spectral weighting in the ultraviolet and blue wavebands, and local generation of light within a given tissue have made it an attractive source of light for techniques ranging from widefield imaging to oximetry and phototherapy. To help guide the future development of this field in the context of molecular imaging, quantitative estimates of the light fluence rates of Cherenkov radiation from a number of radionuclide and external radiotherapy beams in tissue was explored for the first time. Using Monte Carlo simulations, these values were found to be on the order of 0.1 - 1 nW/cm2 per MBq/g for radionuclides and 1 - 10 μW/cm2 per Gy/sec for external radiotherapy beams, dependent on the given waveband and optical properties. For phototherapy applications, the total light fluence was found to be on the order of nJ/cm2 for radionuclides, and mJ/cm2 for radiotherapy beams. To validate these findings, experimental validation was completed with an MV x-ray photon beam incident onto a tissue phantom, confirming the magnitudes of the simulation values. The results indicate that diagnostic potential is reasonable for Cherenkov excitation of molecular probes, but phototherapy may remain elusive at these relatively low fluence values.

  4. Cherenkov radiation fluence estimates in tissue for molecular imaging and therapy applications

    International Nuclear Information System (INIS)

    Cherenkov radiation has recently emerged as an interesting phenomenon for a number of applications in the biomedical sciences. Its unique properties, including broadband emission spectrum, spectral weight in the ultraviolet and blue wavebands, and local generation of light within a given tissue, have made it an attractive new source of light within tissue for molecular imaging and phototherapy applications. While several studies have investigated the total Cherenkov light yield from radionuclides in units of [photons/decay], further consideration of the light propagation in tissue is necessary to fully consider the utility of this signal in vivo. Therefore, to help further guide the development of this novel field, quantitative estimates of the light fluence rate of Cherenkov radiation from both radionuclides and radiotherapy beams in a biological tissue are presented for the first time. Using Monte Carlo simulations, these values were found to be on the order of 0.01–1 nW cm−2 per MBq g−1 for radionuclides, and 1–100 μW cm−2 per Gy s−1 for external radiotherapy beams, dependent on the given waveband, optical properties, and radiation source. For phototherapy applications, the total light fluence was found to be on the order of nJ cm−2 for radionuclides, and mJ cm−2 for radiotherapy beams. The results indicate that diagnostic potential is reasonable for Cherenkov excitation of molecular probes, but phototherapy may remain elusive at such exceedingly low fluence values. The results of this study are publicly available for distribution online at www.dartmouth.edu/optmed/. (paper)

  5. DELPHI's Ring Imaging Cherenkov Chamber

    CERN Multimedia

    1989-01-01

    The hundreds of mirrors around this Ring Imaging Cherenkov Chamber reflect cones of light created by fast moving particles to a detector. The velocity of a particle can be measured by the size of the ring produced on the detector. DELPHI, which ran from 1989 to 2000 on the LEP accelerator, was primarily concerned with particle identification.

  6. Calibration of Cherenkov detectors for monoenergetic photon imaging in active interrogation applications

    Energy Technology Data Exchange (ETDEWEB)

    Rose, P.B., E-mail: prose6@gatech.edu; Erickson, A.S., E-mail: anna.erickson@me.gatech.edu

    2015-11-01

    Active interrogation of cargo containers using monoenergetic photons offers a rapid and low-dose approach to search for shielded special nuclear materials. Cherenkov detectors can be used for imaging of the cargo provided that gamma ray energies used in interrogation are well resolved, as the case in {sup 11}B(d,n-γ){sup 12}C reaction resulting in 4.4 MeV and 15.1 MeV photons. While an array of Cherenkov threshold detectors reduces low energy background from scatter while providing the ability of high contrast transmission imaging, thus confirming the presence of high-Z materials, these detectors require a special approach to energy calibration due to the lack of resolution. In this paper, we discuss the utility of Cherenkov detectors for active interrogation with monoenergetic photons as well as the results of computational and experimental studies of their energy calibration. The results of the studies with sources emitting monoenergetic photons as well as complex gamma ray spectrum sources, for example {sup 232}Th, show that calibration is possible as long as the energies of photons of interest are distinct.

  7. Trends in the development of large area photon detectors for Cherenkov light imaging applications

    CERN Document Server

    Nappi, E

    2003-01-01

    Since the successful operations of hi-tech devices at OMEGA, DELPHI and SLD, the technique of Cherenkov light imaging has gone through an impressive and fruitful evolution driven by the conception of novel large area photon detectors. The well-assessed potentialities of thin CsI films, employed as reflective photoconverters in gas counters operated at atmospheric pressure, will be compared with the promising features of hybrid and multianode vacuum photomultipliers. Recently proposed single-photon gaseous detectors based on GEMs will also be reviewed.

  8. Cherenkov imaging and biochemical sensing in vivo during radiation therapy

    Science.gov (United States)

    Zhang, Rongxiao

    While Cherenkov emission was discovered more than eighty years ago, the potential applications of imaging this during radiation therapy have just recently been explored. With approximately half of all cancer patients being treated by radiation at some point during their cancer management, there is a constant challenge to ensure optimal treatment efficiency is achieved with maximal tumor to normal tissue therapeutic ratio. To achieve this, the treatment process as well as biological information affecting the treatment should ideally be effective and directly derived from the delivery of radiation to the patient. The value of Cherenkov emission imaging was examined here, primarily for visualization of treatment monitoring and then secondarily for Cherenkov-excited luminescence for tissue biochemical sensing within tissue. Through synchronized gating to the short radiation pulses of a linear accelerator (200Hz & 3 micros pulses), and applying a gated intensified camera for imaging, the Cherenkov radiation can be captured near video frame rates (30 frame per sec) with dim ambient room lighting. This procedure, sometimes termed Cherenkoscopy, is readily visualized without affecting the normal process of external beam radiation therapy. With simulation, phantoms and clinical trial data, each application of Cherenkoscopy was examined: i) for treatment monitoring, ii) for patient position monitoring and motion tracking, and iii) for superficial dose imaging. The temporal dynamics of delivered radiation fields can easily be directly imaged on the patient's surface. Image registration and edge detection of Cherenkov images were used to verify patient positioning during treatment. Inter-fraction setup accuracy and intra-fraction patient motion was detectable to better than 1 mm accuracy. Cherenkov emission in tissue opens up a new field of biochemical sensing within the tissue environment, using luminescent agents which can be activated by this light. In the first study of

  9. NICHE: The Non-Imaging CHErenkov Array

    CERN Document Server

    Bergman, Douglas

    2012-01-01

    The accurate measurement of the Cosmic Ray (CR) nuclear composition around and above the Knee (~ 10^15.5 eV) has been difficult due to uncertainties inherent to the measurement techniques and/or dependence on hadronic Monte Carlo simulation models required to interpret the data. Measurement of the Cherenkov air shower signal, calibrated with air fluorescence measurements, offers a methodology to provide an accurate measurement of the nuclear composition evolution over a large energy range. NICHE will use an array of widely-spaced, non-imaging Cherenkov counters to measure the amplitude and time-spread of the air shower Cherenkov signal to extract CR nuclear composition measurements and to cross-calibrate the Cherenkov energy and composition measurements with TA/TALE fluorescence and surface detector measurements.

  10. Volcanoes muon imaging using Cherenkov telescopes

    CERN Document Server

    Catalano, Osvaldo; Mineo, Teresa; Cusumano, Giancarlo; Maccarone, Maria Concetta; Pareschi, Giovanni

    2015-01-01

    A detailed understanding of a volcano inner structure is one of the key-points for the volcanic hazards evaluation. To this aim, in the last decade, geophysical radiography techniques using cosmic muon particles have been proposed. By measuring the differential attenuation of the muon flux as a function of the amount of rock crossed along different directions, it is possible to determine the density distribution of the interior of a volcano. Up to now, a number of experiments have been based on the detection of the muon tracks crossing hodoscopes, made up of scintillators or nuclear emulsion planes. Using telescopes based on the atmospheric Cherenkov imaging technique, we propose a new approach to study the interior of volcanoes detecting the Cherenkov light produced by relativistic cosmic-ray muons that survive after crossing the volcano. The Cherenkov light produced along the muon path is imaged as a typical annular pattern containing all the essential information to reconstruct particle direction and energ...

  11. The BRAHMS ring imaging Cherenkov detector

    Science.gov (United States)

    Debbe, R.; Jørgensen, C. E.; Olness, J.; Yin, Z.

    2007-01-01

    A Ring Imaging Cherenkov detector built for the BRAHMS experiment at the Brookhaven RHIC is described. This detector has a high index of refraction gas radiator. Cherenkov light is focused on a photo-multiplier based photon detector with a large spherical mirror. The combination of momentum and ring radius measurement provides particle identification from 2.5 to 35 GeV/ c for pions and kaons and well above 40 GeV/ c for protons during runs that had the radiator index of refraction set at n-1=1700×10-6.

  12. The PHENIX ring imaging Cherenkov detector

    Energy Technology Data Exchange (ETDEWEB)

    Akiba, Y.; Begay, R.; Burwood-Hoy, J.; Chappell, R.B.; Crook, D.W.; Ebisu, K.; Emery, M.S.; Ferrierra, J.; Frawley, A.D.; Hamagaki, H.; Hara, H.; Hayano, R.S.; Hemmick, T.K.; Hibino, M.; Hutter, R.; Kennedy, M.; Kikuchi, J.; Matsumoto, T.; Moscone, G.G.; Nagasaka, Y.; Nishimura, S.; Oyama, K.; Sakaguchi, T.; Salomone, S.; Shigaki, K.; Tanaka, Y.; Walker, J.W.; Wintenberg, A.L.; Young, G.R

    2000-10-11

    The PHENIX experiment at RHIC is primarily a lepton and photon detector. Electron detection takes place in the two central arms of PHENIX, with the primary electron identifier in each arm being a ring imaging Cherenkov detector. This paper contains a description of the two identical RICH detectors and of their expected performance.

  13. Volcanoes muon imaging using Cherenkov telescopes

    Science.gov (United States)

    Catalano, O.; Del Santo, M.; Mineo, T.; Cusumano, G.; Maccarone, M. C.; Pareschi, G.

    2016-01-01

    A detailed understanding of a volcano inner structure is one of the key-points for the volcanic hazards evaluation. To this aim, in the last decade, geophysical radiography techniques using cosmic muon particles have been proposed. By measuring the differential attenuation of the muon flux as a function of the amount of rock crossed along different directions, it is possible to determine the density distribution of the interior of a volcano. Up to now, a number of experiments have been based on the detection of the muon tracks crossing hodoscopes, made up of scintillators or nuclear emulsion planes. Using telescopes based on the atmospheric Cherenkov imaging technique, we propose a new approach to study the interior of volcanoes detecting of the Cherenkov light produced by relativistic cosmic-ray muons that survive after crossing the volcano. The Cherenkov light produced along the muon path is imaged as a typical annular pattern containing all the essential information to reconstruct particle direction and energy. Our new approach offers the advantage of a negligible background and an improved spatial resolution. To test the feasibility of our new method, we have carried out simulations with a toy-model based on the geometrical parameters of ASTRI SST-2M, i.e. the imaging atmospheric Cherenkov telescope currently under installation onto the Etna volcano. Comparing the results of our simulations with previous experiments based on particle detectors, we gain at least a factor of 10 in sensitivity. The result of this study shows that we resolve an empty cylinder with a radius of about 100 m located inside a volcano in less than 4 days, which implies a limit on the magma velocity of 5 m/h.

  14. Wavelet Imaging Cleaning Method for Atmospheric Cherenkov Telescopes

    OpenAIRE

    Lessard, R. W.; Cayón, L.; Sembroski, G.H.; Gaidos, J. A.

    2001-01-01

    We present a new method of image cleaning for imaging atmospheric Cherenkov telescopes. The method is based on the utilization of wavelets to identify noise pixels in images of gamma-ray and hadronic induced air showers. This method selects more signal pixels with Cherenkov photons than traditional image processing techniques. In addition, the method is equally efficient at rejecting pixels with noise alone. The inclusion of more signal pixels in an image of an air shower allows for a more ac...

  15. The Ring Imaging Cherenkov Detectors for LHCb

    CERN Document Server

    Papanestis, Antonis

    2005-01-01

    The success of the LHCb experiment depends heavily on particle identification over the momentum 2-100 GeV/c. To meet this challenge, LHCb uses a Ring Imaging Cherenkov (RICH) system composed of two detectors with three radiators. RICH1 has both aerogel and gas (C$_4$F$_{10}$) radiators, while RICH2 has only a gas (CF$_4$) radiator. The design of RICH1 is almost complete, whereas RICH2 has been constructed and installed (Nov 2005). Novel Hybrid Photon Detectors (HPDs) have been developed in collaboration with industry to detect the Cherenkov photons. A silicon pixel detector bump-bonded to a readout chip is encapsulated in a vacuum tube. A bi-alkali photocathode is deposited on the inside of the quartz entrance window to convert photons in the range 200-600 nm. The pixel chip is manufactured in 0.25 $\\mu$m deep-submicron radiation-tolerant technology and consists of 1024 logical pixels, each pixel having an area of 0.5 mm x 05. Mm. Photo-electrons are accelerated by a 20kV potential, resulting in a signal of ...

  16. Test of a ring imaging Cherenkov counter

    International Nuclear Information System (INIS)

    We have tested a ring imaging Cherenkov counter with readout of the projection chamber type. A specific detector response of N0=80 cm-1 was measured which corresponds to 8 photoelectrons per event in a 1.60 m long nitrogen radiator. The resolution of the ring radius was measured to be Δr/r=3.6%. The crosstalk between neighboring wires due to photons generated in the avalanche process was estimated to contribute up to 50% per hit. It was reduced considerably by inserting shielding walls between the wires and by adding C2H6 or iC4H10 to the CH4-TMAE gas mixture. (orig.)

  17. Applications of Cherenkov Light Emission for Dosimetry in Radiation Therapy

    Science.gov (United States)

    Glaser, Adam Kenneth

    Since its discovery in the 1930's, the Cherenkov effect has been paramount in the development of high-energy physics research. It results in light emission from charged particles traveling faster than the local speed of light in a dielectric medium. The ability of this emitted light to describe a charged particle's trajectory, energy, velocity, and mass has allowed scientists to study subatomic particles, detect neutrinos, and explore the properties of interstellar matter. However, only recently has the phenomenon been considered in the practical context of medical physics and radiation therapy dosimetry, where Cherenkov light is induced by clinical x-ray photon, electron, and proton beams. To investigate the relationship between this phenomenon and dose deposition, a Monte Carlo plug-in was developed within the Geant4 architecture for medically-oriented simulations (GAMOS) to simulate radiation-induced optical emission in biological media. Using this simulation framework, it was determined that Cherenkov light emission may be well suited for radiation dosimetry of clinically used x-ray photon beams. To advance this application, several novel techniques were implemented to realize the maximum potential of the signal, such as time-gating for maximizing the signal to noise ratio (SNR) and Cherenkov-excited fluorescence for generating isotropic light release in water. Proof of concept experiments were conducted in water tanks to demonstrate the feasibility of the proposed method for two-dimensional (2D) projection imaging, three-dimensional (3D) parallel beam tomography, large field of view 3D cone beam tomography, and video-rate dynamic imaging of treatment plans for a number of common radiotherapy applications. The proposed dosimetry method was found to have a number of unique advantages, including but not limited to its non-invasive nature, water-equivalence, speed, high-resolution, ability to provide full 3D data, and potential to yield data in-vivo. Based on

  18. GAW (Gamma Air Watch) a novel imaging Cherenkov telescope

    CERN Document Server

    Cusumano, G; Biondo, B; Catalano, O; Giarrusso, S; Gugliotta, G; La Fata, L; Maccarone, M C; Mangano, A; Mineo, T; Russo, F; Sacco, B

    2001-01-01

    GAW (Gamma Air Watch) is a new imaging Cherenkov telescope designed for observation of very high-energy gamma-ray sources. GAW will be equipped with a 3 meter diameter Fresnel lens as light collector and with an array of 300 multi-anode photomultipliers at the focal plane. The pixel size will be 4 arcmin wide for a total field of view of 10.5 degrees. Whith respect to the planned imaging Cherenkov telescopes (CANGAROO III, HESS, MAGIC, VERITAS) GAW follows a different approach for what concerns both the optical system and the detection working mode: the Cherenkov light collector is a single acrylic flat Fresnel lens (instead of mirrors) that allows to achieve wide field of view; the photomultipliers operate in single photoelectron counting mode (instead of charge integration). The single photoelectron counting mode allows to reach a low energy threshold of ~200 GeV, in spite of the relatively small dimension of the GAW optic system.

  19. Detection of tau neutrinos by imaging air Cherenkov telescopes

    Science.gov (United States)

    Góra, D.; Bernardini, E.

    2016-09-01

    This paper investigates the potential to detect tau neutrinos in the energy range of 1-1000 PeV searching for very inclined showers with imaging Cherenkov telescopes. A neutrino induced tau lepton escaping from the Earth may decay and initiate an air shower which can be detected by a fluorescence or Cherenkov telescope. We present here a study of the detection potential of Earth-skimming neutrinos taking into account neutrino interactions in the Earth crust, local matter distributions at various detector sites, the development of tau-induced showers in air and the detection of Cherenkov photons with IACTs. We analyzed simulated shower images on the camera focal plane and implemented generic reconstruction chains based on Hillas parameters. We find that present IACTs can distinguish air showers induced by tau neutrinos from the background of hadronic showers in the PeV-EeV energy range. We present the neutrino trigger efficiency obtained for a few configurations being considered for the next-generation Cherenkov telescopes, i.e. the Cherenkov Telescope Array. Finally, for a few representative neutrino spectra expected from astrophysical sources, we compare the expected event rates at running IACTs to what is expected for the dedicated IceCube neutrino telescope.

  20. MO-A-BRD-06: In Vivo Cherenkov Video Imaging to Verify Whole Breast Irradiation Treatment

    International Nuclear Information System (INIS)

    Purpose: To show in vivo video imaging of Cherenkov emission (Cherenkoscopy) can be acquired in the clinical treatment room without affecting the normal process of external beam radiation therapy (EBRT). Applications of Cherenkoscopy, such as patient positioning, movement tracking, treatment monitoring and superficial dose estimation, were examined. Methods: In a phase 1 clinical trial, including 12 patients undergoing post-lumpectomy whole breast irradiation, Cherenkov emission was imaged with a time-gated ICCD camera synchronized to the radiation pulses, during 10 fractions of the treatment. Images from different treatment days were compared by calculating the 2-D correlations corresponding to the averaged image. An edge detection algorithm was utilized to highlight biological features, such as the blood vessels. Superficial dose deposited at the sampling depth were derived from the Eclipse treatment planning system (TPS) and compared with the Cherenkov images. Skin reactions were graded weekly according to the Common Toxicity Criteria and digital photographs were obtained for comparison. Results: Real time (fps = 4.8) imaging of Cherenkov emission was feasible and feasibility tests indicated that it could be improved to video rate (fps = 30) with system improvements. Dynamic field changes due to fast MLC motion were imaged in real time. The average 2-D correlation was about 0.99, suggesting the stability of this imaging technique and repeatability of patient positioning was outstanding. Edge enhanced images of blood vessels were observed, and could serve as unique biological markers for patient positioning and movement tracking (breathing). Small discrepancies exists between the Cherenkov images and the superficial dose predicted from the TPS but the former agreed better with actual skin reactions than did the latter. Conclusion: Real time Cherenkoscopy imaging during EBRT is a novel imaging tool that could be utilized for patient positioning, movement tracking

  1. MO-A-BRD-06: In Vivo Cherenkov Video Imaging to Verify Whole Breast Irradiation Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, R; Glaser, A [Dartmouth College, Hanover, NH - New Hampshire (United States); Jarvis, L [Dartmouth-Hitchcock Medical Center, City Of Lebanon, New Hampshire (United States); Gladstone, D [Dartmouth-Hitchcock Medical Center, Hanover, City of Lebanon (Lebanon); Andreozzi, J; Hitchcock, W; Pogue, B [Dartmouth College, Hanover, NH (United States)

    2014-06-15

    Purpose: To show in vivo video imaging of Cherenkov emission (Cherenkoscopy) can be acquired in the clinical treatment room without affecting the normal process of external beam radiation therapy (EBRT). Applications of Cherenkoscopy, such as patient positioning, movement tracking, treatment monitoring and superficial dose estimation, were examined. Methods: In a phase 1 clinical trial, including 12 patients undergoing post-lumpectomy whole breast irradiation, Cherenkov emission was imaged with a time-gated ICCD camera synchronized to the radiation pulses, during 10 fractions of the treatment. Images from different treatment days were compared by calculating the 2-D correlations corresponding to the averaged image. An edge detection algorithm was utilized to highlight biological features, such as the blood vessels. Superficial dose deposited at the sampling depth were derived from the Eclipse treatment planning system (TPS) and compared with the Cherenkov images. Skin reactions were graded weekly according to the Common Toxicity Criteria and digital photographs were obtained for comparison. Results: Real time (fps = 4.8) imaging of Cherenkov emission was feasible and feasibility tests indicated that it could be improved to video rate (fps = 30) with system improvements. Dynamic field changes due to fast MLC motion were imaged in real time. The average 2-D correlation was about 0.99, suggesting the stability of this imaging technique and repeatability of patient positioning was outstanding. Edge enhanced images of blood vessels were observed, and could serve as unique biological markers for patient positioning and movement tracking (breathing). Small discrepancies exists between the Cherenkov images and the superficial dose predicted from the TPS but the former agreed better with actual skin reactions than did the latter. Conclusion: Real time Cherenkoscopy imaging during EBRT is a novel imaging tool that could be utilized for patient positioning, movement tracking

  2. Lunar Imaging and Ionospheric Calibration for the Lunar Cherenkov Technique

    CERN Document Server

    McFadden, Rebecca; Mevius, Maaijke

    2013-01-01

    The Lunar Cherenkov technique is a promising method for UHE neutrino and cosmic ray detection which aims to detect nanosecond radio pulses produced during particle interactions in the Lunar regolith. For low frequency experiments, such as NuMoon, the frequency dependent dispersive effect of the ionosphere is an important experimental concern as it reduces the pulse amplitude and subsequent chances of detection. We are continuing to investigate a new method to calibrate the dispersive effect of the ionosphere on lunar Cherenkov pulses via Faraday rotation measurements of the Moon's polarised emission combined with geomagnetic field models. We also extend this work to include radio imaging of the Lunar surface, which provides information on the physical and chemical properties of the lunar surface that may affect experimental strategies for the lunar Cherenkov technique.

  3. A G-APD based Camera for Imaging Atmospheric Cherenkov Telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Anderhub, H. [Eidgenoessische Technische Hochschule Zuerich, 8093 Zuerich (Switzerland); Backes, M. [Technische Universitaet Dortmund, 44221 Dortmund (Germany); Biland, A.; Boller, A.; Braun, I. [Eidgenoessische Technische Hochschule Zuerich, 8093 Zuerich (Switzerland); Bretz, T. [Ecole Polytechnique Federale de Lausanne, 1015 Lausanne (Switzerland); Commichau, S.; Commichau, V.; Dorner, D.; Gendotti, A. [Eidgenoessische Technische Hochschule Zuerich, 8093 Zuerich (Switzerland); Grimm, O., E-mail: oliver.grimm@phys.ethz.c [Eidgenoessische Technische Hochschule Zuerich, 8093 Zuerich (Switzerland); Gunten, H. von; Hildebrand, D.; Horisberger, U. [Eidgenoessische Technische Hochschule Zuerich, 8093 Zuerich (Switzerland); Koehne, J.-H. [Technische Universitaet Dortmund, 44221 Dortmund (Germany); Kraehenbuehl, T.; Kranich, D.; Lorenz, E.; Lustermann, W. [Eidgenoessische Technische Hochschule Zuerich, 8093 Zuerich (Switzerland); Mannheim, K. [Universitaet Wuerzburg, 97074 Wuerzburg (Germany)

    2011-02-01

    Imaging Atmospheric Cherenkov Telescopes (IACT) for Gamma-ray astronomy are presently using photomultiplier tubes as photo sensors. Geiger-mode avalanche photodiodes (G-APD) promise an improvement in sensitivity and, important for this application, ease of construction, operation and ruggedness. G-APDs have proven many of their features in the laboratory, but a qualified assessment of their performance in an IACT camera is best undertaken with a prototype. This paper describes the design and construction of a full-scale camera based on G-APDs realized within the FACT project (First G-APD Cherenkov Telescope).

  4. The fluid systems for the SLD Cherenkov ring imaging detector

    International Nuclear Information System (INIS)

    We describe the design and operation of the fluid delivery, monitor and control systems for the SLD barrel Cherenkov Ring Imaging Detector (CRID). The systems deliver drift gas (C2H6 + TMAE), radiator gas (C5F12 + N2) and radiator liquid (C6F14). Measured critical quantities such as electron lifetime in the drift gas and ultra-violet (UV) transparencies of the radiator fluids, together with the operational experience, are also reported

  5. The Ring Imaging Cherenkov detector (RICH) of the AMS experiment

    CERN Document Server

    Barão, F; Alcaraz, J; Arruda, L; Barrau, A; Barreira, G; Belmont, E; Berdugo, J; Brinet, M; Buénerd, M; Casadei, D; Casaus, J; Cortina, E; Delgado, C; Díaz, C; Derome, L; Eraud, L; Garcia-Lopez, R J; Gallin-Martel, L; Giovacchini, F; Gonçalves, P; Lanciotti, E; Laurenti, G; Malinine, A; Maña, C; Marin, J; Martínez, G; Menchaca-Rocha, A; Molla, M; Palomares, C; Panniello, M; Pereira, R; Pimenta, M; Protasov, K; Sánchez, E; Seo, E S; Sevilla, N; Torrento, A; Vargas-Trevino, M; Veziant, O

    2006-01-01

    The Alpha Magnetic Spectrometer (AMS) experiment to be installed on the International Space Station (ISS) will be equipped with a proximity focusing Ring Imaging Cherenkov (RICH) detector for measuring the electric charge and velocity of the charged cosmic particles. A RICH prototype consisting of 96 photomultiplier units, including a piece of the conical reflector, was built and its performance evaluated with ion beam data. Preliminary results of the in-beam tests performed with ion fragments resulting from collisions of a 158 GeV/c/nuc primary beam of Indium ions (CERN SPS) on a Pb target are reported. The collected data included tests to the final front-end electronics and to different aerogel radiators. Cherenkov rings for a large range of charged nuclei and with reflected photons were observed. The data analysis confirms the design goals. Charge separation up to Fe and velocity resolution of the order of 0.1% for singly charged particles are obtained.

  6. The Ring Imaging CHerenkov Detectors of the LHCb Experiment

    CERN Document Server

    Perego, Davide Luigi

    2012-01-01

    Particle identification is a fundamental requirement of the LHCb experiment to fulfill its physics programme. Positive hadron identification is performed by two Ring Imaging CHerenkov (RICH) detectors. This system covers the full angular acceptance of the experiment and is equipped with three Cherenkov radiators to identify particles in a wide momentum range from1 GeV/ c up to 100 GeV/ c . The Hybrid Photon Detectors (HPDs) located outside the detector acceptance provide the photon detection with 500,000 channels. Specific read–out electronics has been developed to readout and process data from the HPDs including data transmission and power distribution. The operation and performanceoftheRICHsystemare ensuredbythe constant controland monitoringoflowandhighvoltage systems,of thegas qualityandenvironmental parameters,ofthe mirror alignment,and finallyofthe detector safety. The description of the LHCb RICH is given. The experience in operating the detector at the Large Hadron Collider is presented and discusse...

  7. Detection of tau neutrinos by Imaging Air Cherenkov Telescopes

    CERN Document Server

    Gora, Dariusz

    2015-01-01

    This paper investigates the potential to detect tau neutrinos in the energy range of 1-1000 PeV searching for very inclined showers with imaging Cherenkov telescopes. A neutrino induced tau lepton escaping from the Earth may decay and initiate an air shower which can be detected by a fluorescence or Cherenkov telescope. We present here a study of the detection potential of Earth-skimming neutrinos taking into account neutrino interactions in the Earth crust, local matter distributions at various detector sites, the development of tau-induced showers in air and the detection of Cherenkov photons with IACTs. We analysed simulated shower images on the camera focal plane and implemented generic reconstruction chains based on Hillas parameters. We find that present IACTs can distinguish air showers induced by tau neutrinos from the background of hadronic showers in the PeV-EeV energy range. We present the neutrino trigger efficiency obtained for a few configurations being considered for the next-generation Cherenk...

  8. Detection of tau neutrinos by Imaging Air Cherenkov Telescopes

    CERN Document Server

    Gora, Dariusz

    2016-01-01

    This paper investigates the potential to detect tau neutrinos in the energy range of 1-1000 PeV searching for very inclined showers with imaging Cherenkov telescopes. A neutrino induced tau lepton escaping from the Earth may decay and initiate an air shower which can be detected by a fluorescence or Cherenkov telescope. We present here a study of the detection potential of Earth-skimming neutrinos taking into account neutrino interactions in the Earth crust, local matter distributions at various detector sites, the development of tau-induced showers in air and the detection of Cherenkov photons with IACTs. We analyzed simulated shower images on the camera focal plane and implemented generic reconstruction chains based on Hillas parameters. We find that present IACTs can distinguish air showers induced by tau neutrinos from the background of hadronic showers in the PeV-EeV energy range. We present the neutrino trigger efficiency obtained for a few configurations being considered for the next-generation Cherenk...

  9. Status of the development of large area photon detectors based on THGEMs and hybrid MPGD architectures for Cherenkov imaging applications

    Science.gov (United States)

    Alexeev, M.; Birsa, R.; Bradamante, F.; Bressan, A.; Büchele, M.; Chiosso, M.; Ciliberti, P.; Torre, S. Dalla; Dasgupta, S.; Denisov, O.; Duic, V.; Finger, M.; Finger, M.; Fischer, H.; Giorgi, M.; Gobbo, B.; Gregori, M.; Herrmann, F.; Königsmann, K.; Levorato, S.; Maggiora, A.; Martin, A.; Menon, G.; Steiger, K.; Novy, J.; Panzieri, D.; Pereira, F. A.; Santos, C. A.; Sbrizzai, G.; Schiavon, P.; Schopferer, S.; Slunecka, M.; Sozzi, F.; Steiger, L.; Sulc, M.; Takekawa, S.; Tessarotto, F.; Veloso, J. F. C. A.; Makke, N.

    2016-07-01

    We report about the development status of large area gaseous single photon detectors based on a novel hybrid concept for RICH applications. The hybrid concept combines Thick Gaseous Electron Multipliers (THGEMs) coupled to CsI, working as a photon sensitive pre-amplification stage, and Micromegas, as a multiplication stage. The most recent achievements within the research and development programme consist in the assembly and study of 300 × 300mm2 hybrid photon detectors, the optimization of front-end electronics, and engineering towards large area detectors. Hybrid detectors with an active area of 300 × 300mm2 have been successfully operated in laboratory conditions and at a CERN PS T10 test beam, achieving effective gains in the order of 105 and good time resolution (σ = 7 ns); APV25 front-end chips have been coupled to the detector resulting in noise levels lower than 1000 electrons; the production and characterization of 300 × 600mm2 THGEMs is ongoing. A set of hybrid detectors with 600 × 600mm2 active area is envisaged to upgrade COMPASS RICH-1 at CERN in 2016.

  10. The TACTIC atmospheric Cherenkov Imaging telescope

    CERN Document Server

    Koul, R; Kaul, S K; Kaul, S R; Kumar, N; Yadav, K K; Bhatt, N; Venugopal, K; Goyal, H C; Kothari, M; Chandra, P; Rannot, R C; Dhar, V K; Koul, M K; Kaul, R K; Kotwal, S; Chanchalani, K; Thoudam, S; Chouhan, N; Sharma, M; Bhattacharya, S; Sahayanathan, S

    2007-01-01

    The TACTIC $\\gamma$-ray telescope, equipped with a light collector of area $\\sim$9.5m$^2$ and a medium resolution imaging camera of 349-pixels, has been in operation at Mt.Abu, India since 2001. This paper describes the main features of its various subsystems and its overall performance with regard to (a) tracking accuracy of its 2-axes drive system, (b) spot size of the light collector, (c) back-end signal processing electronics and topological trigger generation scheme, (d) data acquisition and control system and (e) relative and absolute gain calibration methodology. Using a trigger field of view of 11$\\times$11 pixels ($\\sim$ 3.4$^\\circ nsiderable scope for the TACTIC telescope to monitor similar TeV $\\gamma$-ray emission activity from other active galactic nuclei on a long term basis.

  11. Ultra-high resolution of radiocesium distribution detection based on Cherenkov light imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Seiichi, E-mail: s-yama@met.nagoya-u.ac.jp [Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine (Japan); Ogata, Yoshimune [Department of Radiological and Medical Laboratory Sciences, Nagoya University Graduate School of Medicine (Japan); Kawachi, Naoki; Suzui, Nobuo; Yin, Yong-Gen; Fujimaki, Shu [Radiotracer Imaging Group, Japan Atomic Energy Agency (Japan)

    2015-03-21

    After the nuclear disaster in Fukushima, radiocesium contamination became a serious scientific concern and research of its effects on plants increased. In such plant studies, high resolution images of radiocesium are required without contacting the subjects. Cherenkov light imaging of beta radionuclides has inherently high resolution and is promising for plant research. Since {sup 137}Cs and {sup 134}Cs emit beta particles, Cherenkov light imaging will be useful for the imaging of radiocesium distribution. Consequently, we developed and tested a Cherenkov light imaging system. We used a high sensitivity cooled charge coupled device (CCD) camera (Hamamatsu Photonics, ORCA2-ER) for imaging Cherenkov light from {sup 137}Cs. A bright lens (Xenon, F-number: 0.95, lens diameter: 25 mm) was mounted on the camera and placed in a black box. With a 100-μm {sup 137}Cs point source, we obtained 220-μm spatial resolution in the Cherenkov light image. With a 1-mm diameter, 320-kBq {sup 137}Cs point source, the source was distinguished within 2-s. We successfully obtained Cherenkov light images of a plant whose root was dipped in a {sup 137}Cs solution, radiocesium-containing samples as well as line and character phantom images with our imaging system. Cherenkov light imaging is promising for the high resolution imaging of radiocesium distribution without contacting the subject.

  12. Characterization study of silica aerogel for Cherenkov imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sallaz-Damaz, Y. [LPSC, IN2P3/CNRS, 53 av. des Martyrs, 38026 Grenoble Cedex (France); Derome, L., E-mail: derome@lpsc.in2p3.f [LPSC, IN2P3/CNRS, 53 av. des Martyrs, 38026 Grenoble Cedex (France); Mangin-Brinet, M.; Loth, M.; Protasov, K.; Putze, A.; Vargas-Trevino, M.; Veziant, O.; Buenerd, M. [LPSC, IN2P3/CNRS, 53 av. des Martyrs, 38026 Grenoble Cedex (France); Menchaca-Rocha, A.; Belmont, E.; Vargas-Magana, M.; Leon-Vargas, H.; Ortiz-Velasquez, A. [Instituto de Fisica, UNAM, AP 20-364, Mexico DF (Mexico); Malinine, A. [University of Maryland, College Park, MD 20742 (United States); Barao, F.; Pereira, R. [LIP, Avenida Elias Garcia 14-1, P - 1000 Lisboa (Portugal); Bellunato, T.; Matteuzzi, C.; Perego, D.L. [Universita degli Studi di Milano-Bicocca and INFN, Milano (Italy)

    2010-03-01

    Different methods to measure the characteristics of silica aerogel tiles used as Cherenkov radiator in the CREAM and AMS experiments have been investigated to optimize the detector performances. The measurement accuracy dictated by the physics objectives on the velocity and charge resolutions set stringent requirements on the aerogel refractive index determination, namely DELTAnapprox1.5x10{sup -4} and DELTAnapprox5x10{sup -4} for the AMS and CREAM imagers, respectively. The matching of such accuracies for this material turned out to be a metrological challenge, and finally led to a full R and D program, to develop an appropriate characterization procedure. Preliminary studies performed with a standard refractive index measurement technique (laser beam deviation by a prism) have revealed a significant systematic index nonuniformity for the AMS tiles at a level (10{sup -3}), not acceptable considering the aimed accuracy. These large variations were confirmed in a beam test. A second method, mapping the transverse index gradient by deflection of a laser beam entering normally to the tile has then been developed. It is shown that this procedure is suitable to reach the required accuracy, at the price of using both methods combined. The several hundreds of tiles of the radiator plane of the CREAM and AMS Cherenkov imagers were characterized using a simplified procedure, however, appropriate for each case, compromising between the amount of work and the time available. The experimental procedures and set-ups used are described in the text, and the obtained results are reported.

  13. Workshop on Non-Imaging Cherenkov at High Energy

    CERN Document Server

    2013-01-01

    The non-Imaging Cherenkov air shower measurement technique holds great promise in furthering our understanding the Knee-to-Ankle region of the cosmic ray spectrum. In particular, this technique offers a unique way to determine the evolution of the cosmic ray nuclear composition, and an example is given by the recent spectrum results of the Tunka Collaboration. With this in mind, we are organizing a workshop, to be held at the University of Utah, to bring together the various practitioners of this cosmic ray measurement technique to share simulations, analyses, detector designs, and past experimental results amongst the community. The workshop will also be in support of our effort, NICHE, to extend the reach of the TA/TALE detector systems down to the Knee. We anticipate that the workshop will result in a white paper on the scientific importance of these high-energy cosmic ray measurements and on using the Cherenkov technique to accomplish them. Our goal is to have contributions from members of the previous ge...

  14. The HERMES dual-radiator ring imaging Cherenkov detector

    CERN Document Server

    Akopov, N; Bailey, K; Bernreuther, S; Bianchi, N; Capitani, G P; Carter, P; Cisbani, E; De Leo, R; De Sanctis, E; De Schepper, D; Dzhordzhadze, V; Filippone, B W; Frullani, S; Garibaldi, F; Hansen, J O; Hommez, B; Iodice, M; Jackson, H E; Jung, P; Kaiser, R; Kanesaka, J; Kowalczyk, R; Lagamba, L; Maas, A; Muccifora, V; Nappi, E; Negodaeva, K; Nowak, Wolf-Dieter; O'Connor, T; O'Neill, T G; Potterveld, D H; Ryckbosch, D; Sakemi, Y; Sato, F; Schwind, A; Shibata, T A; Suetsugu, K; Thomas, E; Tytgat, M; Urciuoli, G M; Van De Kerckhove, K; Van De Vyver, R; Yoneyama, S; Zhang, L F; Zohrabyan, H G

    2002-01-01

    The construction and use of a dual radiator Ring Imaging Cherenkov (RICH) detector is described. This instrument was developed for the HERMES experiment at DESY which emphasises measurements of semi-inclusive deep-inelastic scattering. It provides particle identification for pions, kaons, and protons in the momentum range from 2 to 15 GeV, which is essential to these studies. The instrument uses two radiators, C sub 4 F sub 1 sub 0 , a heavy fluorocarbon gas, and a wall of silica aerogel tiles. The use of aerogel in a RICH detector has only recently become possible with the development of clear, large, homogeneous and hydrophobic aerogel. A lightweight mirror was constructed using a newly perfected technique to make resin-coated carbon-fiber surfaces of optical quality. The photon detector consists of 1934 photomultiplier tubes (PMT) for each detector half, held in a soft steel matrix to provide shielding against the residual field of the main spectrometer magnet.

  15. The HERMES dual-radiator ring imaging Cherenkov detector

    International Nuclear Information System (INIS)

    The construction and use of a dual radiator Ring Imaging Cherenkov (RICH) detector is described. This instrument was developed for the HERMES experiment at DESY which emphasises measurements of semi-inclusive deep-inelastic scattering. It provides particle identification for pions, kaons, and protons in the momentum range from 2 to 15 GeV, which is essential to these studies. The instrument uses two radiators, C4F10, a heavy fluorocarbon gas, and a wall of silica aerogel tiles. The use of aerogel in a RICH detector has only recently become possible with the development of clear, large, homogeneous and hydrophobic aerogel. A lightweight mirror was constructed using a newly perfected technique to make resin-coated carbon-fiber surfaces of optical quality. The photon detector consists of 1934 photomultiplier tubes (PMT) for each detector half, held in a soft steel matrix to provide shielding against the residual field of the main spectrometer magnet

  16. Characterization study of silica aerogel for Cherenkov imaging

    International Nuclear Information System (INIS)

    Different methods to measure the characteristics of silica aerogel tiles used as Cherenkov radiator in the CREAM and AMS experiments have been investigated to optimize the detector performances. The measurement accuracy dictated by the physics objectives on the velocity and charge resolutions set stringent requirements on the aerogel refractive index determination, namely Δn∼1.5x10-4 and Δn∼5x10-4 for the AMS and CREAM imagers, respectively. The matching of such accuracies for this material turned out to be a metrological challenge, and finally led to a full R and D program, to develop an appropriate characterization procedure. Preliminary studies performed with a standard refractive index measurement technique (laser beam deviation by a prism) have revealed a significant systematic index nonuniformity for the AMS tiles at a level (10-3), not acceptable considering the aimed accuracy. These large variations were confirmed in a beam test. A second method, mapping the transverse index gradient by deflection of a laser beam entering normally to the tile has then been developed. It is shown that this procedure is suitable to reach the required accuracy, at the price of using both methods combined. The several hundreds of tiles of the radiator plane of the CREAM and AMS Cherenkov imagers were characterized using a simplified procedure, however, appropriate for each case, compromising between the amount of work and the time available. The experimental procedures and set-ups used are described in the text, and the obtained results are reported.

  17. Characterization study of silica aerogel for Cherenkov imaging

    Science.gov (United States)

    Sallaz-Damaz, Y.; Derome, L.; Mangin-Brinet, M.; Loth, M.; Protasov, K.; Putze, A.; Vargas-Trevino, M.; Véziant, O.; Buénerd, M.; Menchaca-Rocha, A.; Belmont, E.; Vargas-Magaña, M.; Léon-Vargas, H.; Ortiz-Velàsquez, A.; Malinine, A.; Baraõ, F.; Pereira, R.; Bellunato, T.; Matteuzzi, C.; Perego, D. L.

    2010-03-01

    Different methods to measure the characteristics of silica aerogel tiles used as Cherenkov radiator in the CREAM and AMS experiments have been investigated to optimize the detector performances. The measurement accuracy dictated by the physics objectives on the velocity and charge resolutions set stringent requirements on the aerogel refractive index determination, namely Δn˜1.5×10-4 and Δn˜5×10-4 for the AMS and CREAM imagers, respectively. The matching of such accuracies for this material turned out to be a metrological challenge, and finally led to a full R&D program, to develop an appropriate characterization procedure. Preliminary studies performed with a standard refractive index measurement technique (laser beam deviation by a prism) have revealed a significant systematic index nonuniformity for the AMS tiles at a level (10-3), not acceptable considering the aimed accuracy. These large variations were confirmed in a beam test. A second method, mapping the transverse index gradient by deflection of a laser beam entering normally to the tile has then been developed. It is shown that this procedure is suitable to reach the required accuracy, at the price of using both methods combined. The several hundreds of tiles of the radiator plane of the CREAM and AMS Cherenkov imagers were characterized using a simplified procedure, however, appropriate for each case, compromising between the amount of work and the time available. The experimental procedures and set-ups used are described in the text, and the obtained results are reported.

  18. Study of TeV range cosmic ray detection with Cherenkov imaging techniques

    International Nuclear Information System (INIS)

    The Monte Carlo study of cosmic ray detection in the TeV energy range has been triggered by the authors' interest in the ARTEMIS (Antimatter Research Through the Earth Moon Ion Spectrometer) proposal. The properties of cosmic ray showers detected by Cherenkov imaging in the visible domain are studied. The detection sensitivity and the accuracy of the reconstruction of the parent particle direction using Cherenkov imaging are discussed. The backbone of the study is the atmospheric shower Monte Carlo generator developed by A.M. Hillas. A comparison between nucleon and photon induced showers of Cherenkov detection is also included. (R.P.) 14 refs., 48 figs., 3 tabs

  19. Development of Ring Imaging Cherenkov Detectors for LHCb

    CERN Document Server

    Bellunato, T; Matteuzzi, C

    2003-01-01

    The work described in this thesis has been carried out in the framework of the development program of the Ring Imaging Cherenkov (RICH) detectors of the LHCb experiment. LHCb will operate at the Large Hadron Collider at CERN, and it will perform a wide range of measurements in the b-hadrons realm. The extensive study of CP violation and rare decays in the b-hadron system are the main goals of the experiment. An introduction to CP violation in hadronic interactions is given in chapter 1. The high b-b bar production cross section at the LHC energy will provide an unprecedented amount of data which will give LHCb a unique opportunity for precision tests on a large set of physics channels as well as a promising discovery potential for sources of CP violation arising from physics beyond the Standard Model. The experiment is designed in such a way to optimally match the kinematic structure of events where a pair of b quarks is produced in the collision between to 7 GeV protons. Chapter 2 is devoted to an overview o...

  20. Application of Geiger-mode photosensors in Cherenkov detectors

    Science.gov (United States)

    Gamal, Ahmed; Paul, Bühler; Michael, Cargnelli; Roland, Hohler; Johann, Marton; Herbert, Orth; Ken, Suzuki

    2011-05-01

    Silicon-based photosensors (SiPMs) working in the Geiger-mode represent an elegant solution for the readout of particle detectors working at low-light levels like Cherenkov detectors. Especially the insensitivity to magnetic fields makes this kind of sensors suitable for modern detector systems in subatomic physics which are usually employing magnets for momentum resolution. We are characterizing SiPMs of different manufacturers for selecting sensors and finding optimum operating conditions for given applications. Recently we designed and built a light concentrator prototype with 8×8 cells to increase the active photon detection area of an 8×8 SiPM (Hamamatsu MPPC S10931-100P) array. Monte Carlo studies, measurements of the collection efficiency, and tests with the MPPC were carried out. The status of these developments are presented.

  1. Front-end electronics and data acquisition system for imaging atmospheric Cherenkov telescopes

    International Nuclear Information System (INIS)

    In this paper, a front-end electronics based on an application-specific integrated circuit (ASIC) is presented for the future imaging atmospheric Cherenkov telescopes (IACTs). To achieve this purpose, a 16-channel ASIC chip, PARISROC 2 (Photomultiplier ARray Integrated in SiGe ReadOut Chip) is used in the analog signal processing and digitization. The digitized results are sent to the server by a user-defined User Datagram Protocol/Internet Protocol (UDP/IP) hardcore engine through Ethernet that is managed by a FPGA. A prototype electronics fulfilling the requirements of the Wide Field of View Cherenkov Telescope Array (WFCTA) of the Large High Altitude Air Shower Observatory (LHAASO) project has been designed, fabricated and tested to prove the concept of the design. A detailed description of the development with the results of the test measurements are presented. By using a new input structure and a new configuration of the ASIC, the dynamic range of the circuit is extended. A highly precise-time calibrating algorithm is also proposed, verified and optimized for the mass production. The test results suggest that the proposed electronics design fulfills the general specification of the future IACTs

  2. Multi-anode photon-multiplier readout electronics for the LHCb ring imaging Cherenkov detectors

    CERN Document Server

    Smale, N J

    2004-01-01

    A readout system for the Ring Imaging CHerenkov (RICH) detectors of the LHCb experiment has been developed. Two detector technologies for the measurement of Cherenkov photons are considered, the Multi-Anode Photo-Multiplier Tube (MAPMT) and the Hybrid Photon Detector (HPD), both of which meet the RICH requirements. The properties of the MAPMT are evaluated using a controlled single-photon source; a pixel-to-pixel gain variation of ~3 and a typical signal to noise of ~20 is measured. The relative tube efficiency is found to be reduced by ~26 % due to the detailed focusing structure of the MAPMT device. A radiation hard application-specific integrated circuit (ASIC) chip, the Beetle1.2MA0, has been developed to capture and store signals from a pair of MAPMTs. The Beetle1.2MA0 is built on the architecture of the Beetle family that was designed for silicon strip detectors, the difference being a modified front-end amplifier. The 128 input-channels of the Beetle1.2MA0 have a charge-sensitive pre-amplifier followed...

  3. Front-end electronics and data acquisition system for imaging atmospheric Cherenkov telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y.T., E-mail: chenytao@ynu.edu.cn [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Yunnan University, 650091 Kunming (China); La Taille, C. de [OMEGA (UMS 3605) - IN2P3/CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Suomijärvi, T. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Cao, Z. [Institute of High Energy Physics, 100049 Beijing (China); Deligny, O. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Dulucq, F. [OMEGA (UMS 3605) - IN2P3/CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Ge, M.M. [Yunnan University, 650091 Kunming (China); Lhenry-Yvon, I. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Martin-Chassard, G. [OMEGA (UMS 3605) - IN2P3/CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex (France); Nguyen Trung, T.; Wanlin, E. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Xiao, G.; Yin, L.Q. [Institute of High Energy Physics, 100049 Beijing (China); Yun Ky, B. [Institut de Physique Nucléaire, IN2P3-CNRS, Université Paris-Sud, 91406 Orsay Cedex (France); Zhang, L. [Yunnan University, 650091 Kunming (China); Zhang, H.Y. [Tsinghua University, 100084 Beijing (China); Zhang, S.S.; Zhu, Z. [Institute of High Energy Physics, 100049 Beijing (China)

    2015-09-21

    In this paper, a front-end electronics based on an application-specific integrated circuit (ASIC) is presented for the future imaging atmospheric Cherenkov telescopes (IACTs). To achieve this purpose, a 16-channel ASIC chip, PARISROC 2 (Photomultiplier ARray Integrated in SiGe ReadOut Chip) is used in the analog signal processing and digitization. The digitized results are sent to the server by a user-defined User Datagram Protocol/Internet Protocol (UDP/IP) hardcore engine through Ethernet that is managed by a FPGA. A prototype electronics fulfilling the requirements of the Wide Field of View Cherenkov Telescope Array (WFCTA) of the Large High Altitude Air Shower Observatory (LHAASO) project has been designed, fabricated and tested to prove the concept of the design. A detailed description of the development with the results of the test measurements are presented. By using a new input structure and a new configuration of the ASIC, the dynamic range of the circuit is extended. A highly precise-time calibrating algorithm is also proposed, verified and optimized for the mass production. The test results suggest that the proposed electronics design fulfills the general specification of the future IACTs.

  4. Lunar imaging and ionospheric calibration for the Lunar Cherenkov technique

    NARCIS (Netherlands)

    McFadden, R.; Scholten, O.; Mevius, M.

    2013-01-01

    The Lunar Cherenkov technique is a promising method for UHE neutrino and cosmic ray detection which aims to detect nanosecond radio pulses produced during particle interactions in the Lunar regolith. For low frequency experiments, such as NuMoon, the frequency dependent dispersive effect of the iono

  5. Monitor and control systems for the SLD Cherenkov Ring Imaging Detector

    International Nuclear Information System (INIS)

    To help ensure the stable long-term operation of a Cherenkov Ring Detector at high efficiency, a comprehensive monitor and control system is being developed. This system will continuously monitor and maintain the correct operating temperatures, and will provide an on-line monitor and maintain the correct operating temperatures, and will provide an on-line monitor of the pressures, flows, mixing, and purity of the various fluids. In addition the velocities and trajectories of Cherenkov photoelectrons drifting within the imaging chambers will be measured using a pulsed uv lamp and a fiberoptic light injection system. 9 refs., 6 figs

  6. A Cherenkov imager for the charge measurement of the elements of nuclear cosmic radiation

    International Nuclear Information System (INIS)

    A Cherenkov imager, CHERCAM (Cherenkov Camera) has been designed and built for the CREAM (Cosmic Ray Energetics and Mass) balloon-borne experiment. The instrument will perform charge measurements of nuclear cosmic-ray over a range extending from proton to iron in the energy domain from 1010 to 1015 eV. This work has focused on the development of CHERCAM by creating a simulation of the detector and on the aerogel plan characterization for the radiator. But it has also expanded on the technical aspects of the construction of the detector and its various tests, as well as the development of calibration software and data analysis. (author)

  7. An analog neural network hardware solution to a Cherenkov ring imaging particle identifier

    International Nuclear Information System (INIS)

    This paper describes the implementation of an analog neural network chip (Intel 80170NX) to the pad readout of a Cherenkov ring imaging detector system. A similar system has previously been tested in software in order to separate proton and pion events. The architecture, training and testing in analog hardware is described. (orig.)

  8. Search for long-lived heavy charged particles using a ring imaging Cherenkov technique at LHCb

    NARCIS (Netherlands)

    Aaij, R.; Adeva, B.; Adinolfi, M.; Affolder, A.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Cartelle, P. Alvarez; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; An, L.; Anderlini, L.; Anderson, J.; Andreotti, M.; Andrews, J. E.; Appleby, R. B.; Gutierrez, O. Aquines; Archilli, F.; d'Argent, P.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Baesso, C.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Batozskaya, V.; Battista, V.; Bay, A.; Beaucourt, L.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Bel, L. J.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bertolin, A.; Bettler, M. -O.; Van Beuzekom, M.; Bien, A.; Bifani, S.; Bird, T.; Birnkraut, A.; Bizzeti, A.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Borsato, M.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brett, D.; Britsch, M.; Britton, T.; Brodzicka, J.; Brook, N. H.; Bursche, A.; Buytaert, J.; Cadeddu, S.; Calabrese, R.; Calvi, M.; Calvo Gomez, M.; Campana, P.; Perez, D. Campora; Capriotti, L.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carniti, P.; Carson, L.; Carvalho Akiba, K.; Casanova Mohr, R.; Casse, G.; Cassina, L.; Garcia, L. Castillo; Cattaneo, M.; Cauet, Ch.; Cavallero, G.; Cenci, R.; Charles, M.; Charpentier, Ph.; Chefdeville, M.; Chen, S.; Cheung, S. F.; Chiapolini, N.; Chrzaszcz, M.; Vidal, X. Cid; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coco, V.; Cogan, J.; Cogneras, E.; Cogoni, V.; Cojocariu, L.; Collazuol, G.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Corvo, M.; Counts, I.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Crocombe, A.; CruzTorres, M.; Cunliffe, S.; Currie, R.; D'Ambrosio, C.; Dalseno, J.; David, P. N. Y.; Davis, A.; De Bruyn, K.; De Capua, S.; De Cian, M.; De Miranda, J. M.; De Paula, L.; De Silva, W.; De Simone, P.; Dean, C. T.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Deleage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Dey, B.; Di Canto, A.; Di Ruscio, F.; Dijkstra, H.; Donleavy, S.; Dordei, F.; Dorigo, M.; Dosil Suarez, A.; Dossett, D.; Dovbnya, A.; Dreimanis, K.; Dujany, G.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; ElRifai, I.; Elsasser, Ch.; Ely, S.; Esen, S.; Evans, H. M.; Evans, T.; Falabella, A.; Faerber, C.; Farinelli, C.; Farley, N.; Farry, S.; Fay, R.; Ferguson, D.; Fernandez Albor, V.; Ferrari, F.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fiorini, M.; Firlej, M.; Fitzpatrick, C.; Fiutowski, T.; Fol, P.; Fontana, M.; Fontanelli, F.; Forty, R.; Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Fu, J.; Furfaro, E.; Torreira, A. Gallas; Galli, D.; Gallorini, S.; Gambetta, S.; Gandelman, M.; Gandini, P.; Gao, Y.; Garcia Pardinas, J.; Garofoli, J.; Tico, J. Garra; Garrido, L.; Gascon, D.; Gaspar, C.; Gauld, R.; Gavardi, L.; Gazzoni, G.; Geraci, A.; Gerick, D.; Gersabeck, E.; Gersabeck, M.; Gershon, T.; Ghez, Ph.; Gianelle, A.; Giani, S.; Gibson, V.; Giubega, L.; Gligorov, V. V.; Goebel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.; Gotti, C.; Gandara, M. Grabalosa; Diaz, R. Graciani; Cardoso, L. A. Granado; Grauges, E.; Graverini, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Gruenberg, O.; Gui, B.; Gushchin, E.; Guz, Yu.; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Han, X.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Henry, L.; Hernando Morata, J. A.; van Herwijnen, E.; Hess, M.; Hicheur, A.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Humair, T.; Hussain, N.; Hutchcroft, D.; Hynds, D.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jalocha, J.; Jans, E.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Jurik, N.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Karodia, S.; Kelsey, M.; Kenyon, I. R.; Kenzie, M.; Ketel, T.; Khanji, B.; Khurewathanakul, C.; Klaver, S.; Klimaszewski, K.; Kochebina, O.; Kolpin, M.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucewicz, W.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G.; Lai, A.; Lambert, D.; Lambert, R. W.; Lanfranchi, G.; Langenbruch, C.; Langhans, B.; Latham, T.; Lazzeroni, C.; Le Gac, R.; van Leerdam, J.; Lees, J. P.

    2015-01-01

    A search is performed for heavy long-lived charged particles using 3.0 fb(-1) of proton-proton collisions collected at root s = 7 and 8 TeV with the LHCb detector. The search is mainly based on the response of the ring imaging Cherenkov detectors to distinguish the heavy, slow-moving particles from

  9. Electrostatic design of the barrel CRID (Cherenkov Ring Imaging Detector) and associated measurements

    Energy Technology Data Exchange (ETDEWEB)

    Abe, K.; Hasegawa, K.; Suekane, F.; Yuta, H. (Tohoku Univ., Sendai (Japan). Dept. of Physics); Antilogus, P.; Aston, D.; Bienz, T.; Bird, F.; Dunwoodie, W.; Hallewell, G.; Kawahara, H.; Kwon, Y.; Leith, D.W.G.S.; Muller, D.; Nagamine, T.; Pavel, T.; Ratcliff, B.; Rensing, P.; Schultz, D.; Shapiro, S.; Simopoulos, C.; Solodov, E.; Toge, N.; Va' Vra, J. Williams, H. (Stanford Linear Accelerator Center, Menlo Park, CA (US

    1990-04-01

    We report on the electrostatic design and related measurements of the barrel Cherenkov Ring Imaging Detector for the Stanford Large Detector experiment at the Stanford Linear Accelerator Center Linear Collider. We include test results of photon feedback in TMAE-laden gas, distortion measurements in the drift boxes and corona measurements. 13 refs., 21 figs.

  10. FACT: Towards Robotic Operation of an Imaging Air Cherenkov Telescope

    CERN Document Server

    Biland, A; Backes, M; Boccone, V; Braun, I; Bretz, T; Buss, J; Cadoux, F; Commichau, V; Djambazov, L; Dorner, D; Einecke, S; Eisenacher, D; Gendotti, A; Grimm, O; von Gunten, H; Haller, C; Hildebrand, D; Horisberger, U; Huber, B; Kim, K -S; Knoetig, M L; Koehne, J -H; Kraehenbuehl, T; Krumm, B; Lee, M; Lorenz, E; Lustermann, W; Lyard, E; Mannheim, K; Meharga, M; Meier, K; Montaruli, T; Neise, D; Nessi-Tedaldi, F; Overkemping, A -K; Paravac, A; Pauss, F; Renker, D; Rhode, W; Ribordy, M; Roeser, U; Stucki, J -P; Schneider, J; Steinbring, T; Temme, F; Thaele, J; Tobler, S; Viertel, G; Vogler, P; Walter, R; Warda, K; Weitzel, Q; Zaenglein, M

    2013-01-01

    The First G-APD Cherenkov Telescope (FACT) became operational at La Palma in October 2011. Since summer 2012, due to very smooth and stable operation, it is the first telescope of its kind that is routinely operated from remote, without the need for a data-taking crew on site. In addition, many standard tasks of operation are executed automatically without the need for manual interaction. Based on the experience gained so far, some alterations to improve the safety of the system are under development to allow robotic operation in the future. We present the setup and precautions used to implement remote operations and the experience gained so far, as well as the work towards robotic operation.

  11. Digital FDIRC: A focused differential internal reflection Cherenkov imaged by SiPM arrays

    Science.gov (United States)

    Marrocchesi, P. S.; Bagliesi, M. G.; Basti, A.; Bigongiari, G.; Bonechi, S.; Brogi, P.; Checchia, C.; Collazuol, G.; Maestro, P.; Morsani, F.; Piemonte, C.; Stolzi, F.; Suh, J. E.; Sulaj, A.

    2016-07-01

    A prototype of an Internal Reflection Cherenkov, equipped with a SiO2 (fused silica) radiator bar optically connected to a cylindrical mirror, was tested at CERN SPS in March 2015 with a beam of relativistic ions obtained from fragmentation of primary argon nuclei at energies 13, 19 and 30 GeV/n. The detector, designed to identify cosmic nuclei, features an imaging focal plane of dimensions ~ 4 cm × 3 cm equipped with 16 arrays of NUV-SiPM (near-ultraviolet sensitive silicon photon avalanche detector) for a total of 1024 sensitive elements. The outstanding performance of the photodetectors (with negligible background in between adjacent photopeaks) allowed us to apply the technique of photon counting to the Cherenkov light collected on the focal plane. Thanks to the fine granularity of the array elements, the Cherenkov pattern was recorded together with the total number of detected photoelectrons increasing as Z2 as a function of the atomic number Z. In this paper, we report the performance of the SiPM arrays and the excellent resolution achieved by the digital Cherenkov prototype in the charge identification of the elements present in the beam.

  12. Cherenkov Video Imaging Allows for the First Visualization of Radiation Therapy in Real Time

    International Nuclear Information System (INIS)

    Purpose: To determine whether Cherenkov light imaging can visualize radiation therapy in real time during breast radiation therapy. Methods and Materials: An intensified charge-coupled device (CCD) camera was synchronized to the 3.25-μs radiation pulses of the clinical linear accelerator with the intensifier set × 100. Cherenkov images were acquired continuously (2.8 frames/s) during fractionated whole breast irradiation with each frame an accumulation of 100 radiation pulses (approximately 5 monitor units). Results: The first patient images ever created are used to illustrate that Cherenkov emission can be visualized as a video during conditions typical for breast radiation therapy, even with complex treatment plans, mixed energies, and modulated treatment fields. Images were generated correlating to the superficial dose received by the patient and potentially the location of the resulting skin reactions. Major blood vessels are visible in the image, providing the potential to use these as biological landmarks for improved geometric accuracy. The potential for this system to detect radiation therapy misadministrations, which can result from hardware malfunction or patient positioning setup errors during individual fractions, is shown. Conclusions: Cherenkoscopy is a unique method for visualizing surface dose resulting in real-time quality control. We propose that this system could detect radiation therapy errors in everyday clinical practice at a time when these errors can be corrected to result in improved safety and quality of radiation therapy

  13. Cherenkov Video Imaging Allows for the First Visualization of Radiation Therapy in Real Time

    Energy Technology Data Exchange (ETDEWEB)

    Jarvis, Lesley A., E-mail: Lesley.a.jarvis@hitchcock.org [Department of Medicine, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire (United States); Norris Cotton Cancer Center at the Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Zhang, Rongxiao [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire (United States); Gladstone, David J. [Department of Medicine, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire (United States); Norris Cotton Cancer Center at the Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire (United States); Jiang, Shudong [Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire (United States); Hitchcock, Whitney [Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire (United States); Friedman, Oscar D.; Glaser, Adam K.; Jermyn, Michael [Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire (United States); Pogue, Brian W. [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire (United States); Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire (United States)

    2014-07-01

    Purpose: To determine whether Cherenkov light imaging can visualize radiation therapy in real time during breast radiation therapy. Methods and Materials: An intensified charge-coupled device (CCD) camera was synchronized to the 3.25-μs radiation pulses of the clinical linear accelerator with the intensifier set × 100. Cherenkov images were acquired continuously (2.8 frames/s) during fractionated whole breast irradiation with each frame an accumulation of 100 radiation pulses (approximately 5 monitor units). Results: The first patient images ever created are used to illustrate that Cherenkov emission can be visualized as a video during conditions typical for breast radiation therapy, even with complex treatment plans, mixed energies, and modulated treatment fields. Images were generated correlating to the superficial dose received by the patient and potentially the location of the resulting skin reactions. Major blood vessels are visible in the image, providing the potential to use these as biological landmarks for improved geometric accuracy. The potential for this system to detect radiation therapy misadministrations, which can result from hardware malfunction or patient positioning setup errors during individual fractions, is shown. Conclusions: Cherenkoscopy is a unique method for visualizing surface dose resulting in real-time quality control. We propose that this system could detect radiation therapy errors in everyday clinical practice at a time when these errors can be corrected to result in improved safety and quality of radiation therapy.

  14. Camera selection for real-time in vivo radiation treatment verification systems using Cherenkov imaging

    Energy Technology Data Exchange (ETDEWEB)

    Andreozzi, Jacqueline M., E-mail: Jacqueline.M.Andreozzi.th@dartmouth.edu; Glaser, Adam K. [Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755 (United States); Zhang, Rongxiao [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States); Jarvis, Lesley A.; Gladstone, David J. [Department of Medicine, Geisel School of Medicine and Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03766 (United States); Pogue, Brian W., E-mail: Brian.W.Pogue@dartmouth.edu [Thayer School of Engineering and Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States)

    2015-02-15

    Purpose: To identify achievable camera performance and hardware needs in a clinical Cherenkov imaging system for real-time, in vivo monitoring of the surface beam profile on patients, as novel visual information, documentation, and possible treatment verification for clinicians. Methods: Complementary metal-oxide-semiconductor (CMOS), charge-coupled device (CCD), intensified charge-coupled device (ICCD), and electron multiplying-intensified charge coupled device (EM-ICCD) cameras were investigated to determine Cherenkov imaging performance in a clinical radiotherapy setting, with one emphasis on the maximum supportable frame rate. Where possible, the image intensifier was synchronized using a pulse signal from the Linac in order to image with room lighting conditions comparable to patient treatment scenarios. A solid water phantom irradiated with a 6 MV photon beam was imaged by the cameras to evaluate the maximum frame rate for adequate Cherenkov detection. Adequate detection was defined as an average electron count in the background-subtracted Cherenkov image region of interest in excess of 0.5% (327 counts) of the 16-bit maximum electron count value. Additionally, an ICCD and an EM-ICCD were each used clinically to image two patients undergoing whole-breast radiotherapy to compare clinical advantages and limitations of each system. Results: Intensifier-coupled cameras were required for imaging Cherenkov emission on the phantom surface with ambient room lighting; standalone CMOS and CCD cameras were not viable. The EM-ICCD was able to collect images from a single Linac pulse delivering less than 0.05 cGy of dose at 30 frames/s (fps) and pixel resolution of 512 × 512, compared to an ICCD which was limited to 4.7 fps at 1024 × 1024 resolution. An intensifier with higher quantum efficiency at the entrance photocathode in the red wavelengths [30% quantum efficiency (QE) vs previous 19%] promises at least 8.6 fps at a resolution of 1024 × 1024 and lower monetary

  15. The image camera of the 17 m diameter air Cherenkov telescope MAGIC

    CERN Document Server

    Ostankov, A P

    2001-01-01

    The image camera of the 17 m diameter MAGIC telescope, an air Cherenkov telescope currently under construction to be installed at the Canary island La Palma, is described. The main goal of the experiment is to cover the unexplored energy window from approx 10 to approx 300 GeV in gamma-ray astrophysics. In its first phase with a classical PMT camera the MAGIC telescope is expected to reach an energy threshold of approx 30 GeV. The operational conditions, the special characteristics of the developed PMTs and their use with light concentrators, the fast signal transfer scheme using analog optical links, the trigger and DAQ organization as well as image reconstruction strategy are described. The different paths being explored towards future camera improvements, in particular the constraints in using silicon avalanche photodiodes and GaAsP hybrid photodetectors in air Cherenkov telescopes are discussed.

  16. Simulation of Imaging Atmospheric Cherenkov Telescopes with CORSIKA and sim_telarray

    OpenAIRE

    Bernlohr, Konrad

    2008-01-01

    Imaging Atmospheric Cherenkov Telescopes (IACTs) have resulted in a breakthrough in very-high energy (VHE) gamma-ray astrophysics. While early IACT installations faced the problem of detecting any sources at all, current instruments are able to see many sources, often over more than two orders of magnitude in energy. As instruments and analysis methods have matured, the requirements for calibration and modelling of physical and instrumental effects have increased. In this article, a set of Mo...

  17. The optical reflector system for the CANGAROO-II imaging atmospheric Cherenkov telescope

    CERN Document Server

    Kawachi, A; Jimbo, J; Kamei, S; Kifune, T; Kubo, H; Kushida, J; Le Bohec, S; Miyawaki, K; Mori, M; Nishijima, K; Patterson, J R; Suzuki, R; Tanimori, T; Yanagita, S; Yoshikoshi, T; Yuki, A

    2001-01-01

    A new imaging atmospheric Cherenkov telescope (CANGAROO-II) with a light-weight reflector has been constructed. Light, robust, and durable mirror facets of containing CFRP (Carbon Fiber Reinforced Plastic) laminates were developed for the telescope. The attitude of each facet can be adjusted by stepping motors. In this paper, we describe the design, manufacturing, alignment procedure, and the performance of the CANGAROO-II optical reflector system.

  18. Cherenkov radiation imaging of beta emitters: in vitro and in vivo results

    International Nuclear Information System (INIS)

    The main purpose of this work was to investigate both in vitro and in vivo Cherenkov radiation (CR) emission coming from 18F and 32P. The main difference between 18F and 32P is mainly the number of the emitted light photons, more precisely the same activity of 32P emits more CR photons with respect to 18F. In vitro results obtained by comparing beta counter measurements with photons average radiance showed that Cherenkov luminescence imaging (CLI) allows quantitative tracer activity measurements. In order to investigate in vivo the CLI approach, we studied an experimental xenograft tumor model of mammary carcinoma (BB1 tumor cells). Cherenkov in vivo dynamic whole body images of tumor bearing mice were acquired and the tumor tissue time activity curves reflected the well-known physiological accumulation of 18F-FDG in malignant tissues with respect to normal tissues. The results presented here show that it is possible to use conventional optical imaging devices for in vitro or in vivo study of beta emitters.

  19. Design and construction of a Cherenkov imager for charge measurement of nuclear cosmic rays

    CERN Document Server

    Bourrion, O; Bondoux, D; Bouly, J L; Bouvier, J; Boyer, B; Brinet, M; Buenerd, M; Damieux, G; Derome, L; Eraud, L; Foglio, R; Fombaron, D; Grondin, D; Lee, M H; Lutz, L; Marton, M; Menchaca-Rocha, A; Pelissier, A; Périé, J N; Putze, A; Roudier, S; Sallaz-Damaz, Y; Seo, E S; Scordilis, J P; Yoon, Y S

    2011-01-01

    A proximity focusing Cherenkov imager called CHERCAM, has been built for the charge measurement of nuclear cosmic rays with the CREAM instrument. It consists of a silica aerogel radiator plane across from a detector plane equipped with 1,600 1" diameter photomultipliers. The two planes are separated by a ring expansion gap. The Cherenkov light yield is proportional to the charge squared of the incident particle. The expected relative light collection accuracy is in the few percents range. It leads to an expected single element separation over the range of nuclear charge Z of main interest 1 < Z < 26. CHERCAM is designed to fly with the CREAM balloon experiment. The design of the instrument and the implemented technical solutions allowing its safe operation in high altitude conditions (radiations, low pressure, cold) are presented.

  20. Design and construction of a Cherenkov imager for charge measurement of nuclear cosmic rays

    Energy Technology Data Exchange (ETDEWEB)

    Bourrion, O; Bernard, C; Bondoux, D; Bouly, J L; Bouvier, J; Boyer, B; Brinet, M; Buenerd, M; Damieux, G; Derome, L; Eraud, L; Foglio, R; Fombaron, D; Grondin, D; Marton, M; Pelissier, A [Laboratoire de Physique Subatomique et de Cosmologie, Universite Joseph Fourier Grenoble 1, CNRS/IN2P3, Institut Polytechnique de Grenoble, 53, rue des Martyrs, Grenoble (France); Lee, M H; Lutz, L [University of Maryland, College Park MD 20742 (United States); Menchaca-Rocha, A [Instituto de Fisica, UNAM, A.P. 20-364, 01000 Mexico DF (Mexico); Perie, J N, E-mail: olivier.bourrion@lpsc.in2p3.fr [Universite de Toulouse, INSA, UPS, Mines Albi, ISAE, ICA (Institut Clement Ader), 133, avenue de Rangueil, F-31077 Toulouse (France)

    2011-06-15

    A proximity focusing Cherenkov imager called CHERCAM, has been built for the charge measurement of nuclear cosmic rays with the CREAM instrument. It consists of a silica aerogel radiator plane across from a detector plane equipped with 1,600 1'' diameter photomultipliers. The two planes are separated by a ring expansion gap. The Cherenkov light yield is proportional to the charge squared of the incident particle. The expected relative light collection accuracy is in the few percents range. It leads to an expected single element separation over the range of nuclear charge Z of main interest 1 {<=} Z{approx}<26. CHERCAM is designed to fly with the CREAM balloon experiment. The design of the instrument and the implemented technical solutions allowing its safe operation in high altitude conditions (radiations, low pressure, cold) are presented.

  1. Studies of Multi-Anode PMTs for a Ring Imaging Cherenkov for CLAS12

    Science.gov (United States)

    Lendacky, Andrew; Benmokhtar, Fatiha; Kubarovsky, Valery; Kim, Andrey

    2015-10-01

    At Thomas Jefferson National Accelerator Facility (TJNAF), the CLAS12 detector in Hall B is undergoing an upgrade. A Ring Imaging Cherenkov (R.I.C.H) detector is being built to improve particle identification in the 3-8 GeV/c momentum range. Approximately four hundred Hamamatsu H121700 Multi-Anode Photomultiplier Tubes (MA-PMTs) are being used in this detector to measure photons emitted through Cherenkov Radiation. These MA-PMTs' characteristics are being tested and measured, and I will be presenting my work about the crosstalk study. Crosstalk is the occurrence of incident light striking one area of the photocathode, but is additionally measured in nearby areas. By using a Class 3b laser in the 470 nm wavelength, and an optical density resembling the single photon emission spectrum, the crosstalk for the H121700 MA-PMTs are measured and categorized into a database for future reference.

  2. Optimal strategies for observation of active galactic nuclei variability with Imaging Atmospheric Cherenkov Telescopes

    CERN Document Server

    Giomi, Matteo; Maier, Gernot

    2016-01-01

    Variable emission is one of the defining characteristic of active galactic nuclei (AGN). While providing precious information on the nature and physics of the sources, variability is often challenging to observe with time- and field-of-view-limited astronomical observatories such as Imaging Atmospheric Cherenkov Telescopes (IACTs). In this work, we address two questions relevant for the observation of sources characterized by AGN-like variability: what is the most time-efficient way to detect such sources, and what is the observational bias that can be introduced by the choice of the observing strategy when conducting blind surveys of the sky. Different observing strategies are evaluated using simulated light curves and realistic instrument response functions of the Cherenkov Telescope Array (CTA), a future gamma-ray observatory. We show that strategies that makes use of very small observing windows, spread over large periods of time, allows for a faster detection of the source, and are less influenced by the...

  3. Evaluation of Multi-Anode Photomultipliers for the CLAS12 Ring-Imaging Cherenkov Detector

    Science.gov (United States)

    Samuel, Jenna

    2015-04-01

    Thomas Jefferson National Accelerator Facility has recently upgraded its Continuous Electron Beam Accelerator Facility (CEBAF) Large Acceptance Spectrometer (CLAS12) to provide a comprehensive study of the complex internal structure and dynamics of the nucleon. The upgrade includes new detectors such as the Ring Imaging Cherenkov detector (RICH). The RICH will use multi-anode photomultipliers (MAPMTs) for the detection of Cherenkov photons. Our study compared two models of Hamamatsu MAPMTs (H8500 and H12700) under consideration for the CLAS12 RICH in terms of their single photoelectron (SPE) peak, dark current, and crosstalk. The MAPMTs were tested inside a light-tight box, using a low intensity laser to simulate single photoelectron events similar to Cherenkov radiation. The H12700's SPE peaks were on average 78% the width of the H8500's peaks. For both models, the probability of dark current was on the order of 10-4. The probability of crosstalk for H8500s was 1.6 to 2.7 times that for H12700s. The H12700s were deemed better because they had negligible crosstalk and dark current while providing a narrower peak for single photoelectron events. Thomas Jefferson National Accelerator Facility, Science Undergraduate Laboratory Internship.

  4. Detection of Shielded Special Nuclear Material With a Cherenkov-Based Transmission Imaging System

    Science.gov (United States)

    Rose, Paul; Erickson, Anna; Mayer, Michael; Jovanovic, Igor

    2015-10-01

    Detection of shielded special nuclear material, SSNM, while in transit, offers a unique challenge. Typical cargo imaging systems are Bremsstrahlung-based and cause an abundance of unnecessary signal in the detectors and doses to the cargo contents and surroundings. Active interrogation with dual monoenergetic photons can unveil the illicit material when coupled with a high-contrast imaging system while imparting significantly less dose to the contents. Cherenkov detectors offer speed, resilience, inherent energy threshold rejection, directionality and scalability beyond the capability of most scintillators. High energy resolution is not a priority when using two well separated gamma rays, 4.4 and 15.1 MeV, generated from low energy nuclear reactions such as 11B(d,n- γ)12C. These gamma rays offer a measure of the effective atomic number, Z, of the cargo by taking advantage of the large difference in photon interaction cross sections, Compton scattering and pair production. This imaging system will be coupled to neutron detectors to provide unique signature of SNM by monitoring delayed neutrons. Our experiments confirm that the Cherenkov imaging system can be used with the monoenergetic source to relate transmission and atomic number of the scanned material.

  5. The possibilities of Cherenkov telescopes to perform cosmic-ray muon imaging of volcanoes

    Science.gov (United States)

    Carbone, Daniele; Catalano, Osvaldo; Cusumano, Giancarlo; Del Santo, Melania; Maccarone, Maria Concetta; Mineo, Teresa; Pareschi, Giovanni; Vercellone, Stefano; Zuccarello, Luciano

    2016-04-01

    Volcanic activity is regulated by the interaction of gas-liquid flow with conduit geometry. Hence, the quantitative understanding of the inner shallow structure of a volcano is mandatory to forecast the occurrence of dangerous stages of activity and mitigate volcanic hazards. Among the techniques used to investigate the underground structure of a volcano, muon imaging offers some advantages, as it provides a fine spatial resolution, and does not require neither spatially dense measurements in active zones, nor the implementation of cost demanding energizing systems, as when electric or active seismic sources are utilized. The principle of muon radiography is essentially the same as X-ray radiography: muons are more attenuated by higher density parts inside the target and thus information about its inner structure are obtained from the differential muon absorption. Up-to-date, muon imaging of volcanic structures has been mainly accomplished with detectors that employ planes of scintillator strips. These telescopes are exposed to different types of background noise (accidental coincidence of vertical shower particles, horizontal high-energy electrons, flux of upward going particles), whose amplitude is high relative to the tiny flux of interest. An alternative technique is based on the detection of the Cherenkov light produced by muons. The latter can be imaged as an annular pattern that contains the information needed to reconstruct both direction and energy of the particle. Cherenkov telescopes have never been utilized to perform muon imaging of volcanoes. Nonetheless, thanks to intrinsic features, they offer the possibility to detect the through-target muon flux with negligible levels of background noise. Under some circumstances, they would also provide a better spatial resolution and acceptance than scintillator-based telescopes. Furthermore, contrarily to the latter systems, Cherenkov detectors allow in-situ measurements of the open-sky energy spectrum of

  6. The Topo-trigger: a new concept of stereo trigger system for imaging atmospheric Cherenkov telescopes

    CERN Document Server

    López-Coto, Rubén; Paoletti, Riccardo; Bigas, Oscar Blanch; Cortina, Juan

    2016-01-01

    Imaging atmospheric Cherenkov telescopes (IACTs) such as the Major Atmospheric Gamma-ray Imaging Cherenkov (MAGIC) telescopes endeavor to reach the lowest possible energy threshold. In doing so the trigger system is a key element. Reducing the trigger threshold is hampered by the rapid increase of accidental triggers generated by ambient light, the so-called Night Sky Background (NSB). In this paper we present a topological trigger, dubbed Topo-trigger, which rejects events on the basis of their relative orientation in the telescope cameras. We have simulated and tested the trigger selection algorithm in the MAGIC telescopes. The algorithm was tested using MonteCarlo simulations and shows a rejection of 85% of the accidental stereo triggers while preserving 99 % of the gamma rays. A full implementation of this trigger system would achieve an increase in collection area between 10 and 20% at the energy threshold. The analysis energy threshold of the instrument is expected to decrease by ?8 %. The selection alg...

  7. The modeling of the nuclear composition measurement performance of the Non-Imaging CHErenkov Array (NICHE)

    CERN Document Server

    Krizmanic, John; Sokolsky, Pierre

    2013-01-01

    In its initial deployment, the Non-Imaging CHErenkov Array (NICHE)will measure the flux and nuclear composition of cosmic rays from below 10^16 eV to 10^18 eV by using measurements of the amplitude and time-spread of the air-shower Cherenkov signal to achieve a robust event-by-event measurement of Xmax and energy. NICHE will have sufficient area and angular acceptance to have significant overlap with TA/TALE, within which NICHE is located, to allow for energy cross-calibration. In order to quantify NICHE's ability to measure the cosmic ray nuclear composition, 4-component composition models were constructed based upon a poly-gonato model of J. Hoerandel using simulated Xmax distributions of the composite composition as a function of energy. These composition distributions were then unfolded into individual components via an analysis technique that included NICHE's simulated Xmax and energy resolution performance as a function of energy as well as the effects of finite event statistics. Details of the construc...

  8. Supernova remnants and pulsar wind nebulae with Imaging Atmospheric Cherenkov Telescopes (IACTs)

    Science.gov (United States)

    Eger, Peter

    2015-08-01

    The observation of very-high-energy (VHE, E > 100 GeV) gamma rays is an excellent tool to study the most energetic and violent environments in the Galaxy. This energy range is only accessible with ground-based instruments such as Imaging Atmospheric Cherenkov Telescopes (IACTs) that reconstruct the energy and direction of the primary gamma ray by observing the Cherenkov light from the induced extended air showers in Earths atmosphere. The main goals of Galactic VHE gamma-ray science are the identification of individual sources of cosmic rays (CRs), such as supernova remnants (SNRs), and the study of other extreme astrophysical objects at the highest energies, such as gamma-ray binaries and pulsar wind nebulae (PWNe). One of the main challenges is the discrimination between leptonic and hadronic gamma-ray production channels. To that end, the gamma-ray signal from each individual source needs to be brought into context with the multi-wavelength environment of the astrophysical object in question, particularly with observations tracing the density of the surrounding interstellar medium, or synchrotron radiation from relativistic electrons. In this review presented at the European Cosmic Ray Symposium 2014 (ECRS2014), the most recent developments in the field of Galactic VHE gamma-ray science are highlighted, with particular emphasis on SNRs and PWNe.

  9. Optimal strategies for observation of active galactic nuclei variability with Imaging Atmospheric Cherenkov Telescopes

    Science.gov (United States)

    Giomi, Matteo; Gerard, Lucie; Maier, Gernot

    2016-07-01

    Variable emission is one of the defining characteristic of active galactic nuclei (AGN). While providing precious information on the nature and physics of the sources, variability is often challenging to observe with time- and field-of-view-limited astronomical observatories such as Imaging Atmospheric Cherenkov Telescopes (IACTs). In this work, we address two questions relevant for the observation of sources characterized by AGN-like variability: what is the most time-efficient way to detect such sources, and what is the observational bias that can be introduced by the choice of the observing strategy when conducting blind surveys of the sky. Different observing strategies are evaluated using simulated light curves and realistic instrument response functions of the Cherenkov Telescope Array (CTA), a future gamma-ray observatory. We show that strategies that makes use of very small observing windows, spread over large periods of time, allows for a faster detection of the source, and are less influenced by the variability properties of the sources, as compared to strategies that concentrate the observing time in a small number of large observing windows. Although derived using CTA as an example, our conclusions are conceptually valid for any IACTs facility, and in general, to all observatories with small field of view and limited duty cycle.

  10. GAW - An Imaging Atmospheric Cherenkov Telescope with Large Field of View

    CERN Document Server

    Cusumano, G; Alberdi, A; Alvarez, M; Assis, P; Biondo, B; Bocchino, F; Brogueira, P; Caballero, J A; Carvajal, M; Castro-Tirado, A J; Catalano, O; Celi, F; Delgado, C; Di Cocco, G; Dominguez, A; Navas, J M Espino; Santo, M C Espirito; Gallardo, M I; García, J E; Giarrusso, S; Gómez, M; Gómez, J L; Gonçalves, P; Guerriero, M; La Barbera, A; La Rosa, G; Lozano, M; Maccarone, M C; Mangano, A; Martel, I; Massaro, E; Mineo, T; Moles, M; Pérez-Bernal, F; Peres-Torres, M A; Pimenta, M; Pina, A; Prada, F; Quesada, J M; Quintana, J M; Quintero, J R; Rodríguez, J; Russo, F; Sacco, B; Sanchez-Conde, M A; Segreto, A; Tome', B; Postigo, A de Ugarte; Vallania, P

    2007-01-01

    GAW, acronym for Gamma Air Watch, is a Research and Development experiment in the TeV range, whose main goal is to explore the feasibility of large field of view Imaging Atmospheric Cherenkov Telescopes. GAW is an array of three relatively small telescopes (2.13 m diameter) which differs from the existing and presently planned projects in two main features: the adoption of a refractive optics system as light collector and the use of single photoelectron counting as detector working mode. The optics system allows to achieve a large field of view (24x24 squared degrees) suitable for surveys of large sky regions. The single photoelectron counting mode in comparison with the charge integration mode improves the sensitivity by permitting also the reconstruction of events with a small number of collected Cherenkov photons. GAW, which is a collaboration effort of Research Institutes in Italy, Portugal and Spain, will be erected in the Calar Alto Observatory (Sierra de Los Filabres - Andalucia, Spain), at 2150 m a.s....

  11. Cherenkov imaging during volumetric modulated arc therapy for real-time radiation beam tracking and treatment response monitoring

    Science.gov (United States)

    Andreozzi, Jacqueline M.; Zhang, Rongxiao; Glaser, Adam K.; Gladstone, David J.; Jarvis, Lesley A.; Pogue, Brian W.

    2016-03-01

    External beam radiotherapy utilizes high energy radiation to target cancer with dynamic, patient-specific treatment plans. The otherwise invisible radiation beam can be observed via the optical Cherenkov photons emitted from interaction between the high energy beam and tissue. Using a specialized camera-system, the Cherenkov emission can thus be used to track the radiation beam on the surface of the patient in real-time, even for complex cases such as volumetric modulated arc therapy (VMAT). Two patients undergoing VMAT of the head and neck were imaged and analyzed, and the viability of the system to provide clinical feedback was established.

  12. Precision optical systems for the new generation of Ring Imaging Cherenkov detectors in high energy physics experiments

    International Nuclear Information System (INIS)

    High precision optical systems are required for the new generation of Ring Imaging Cherenkov detectors in high energy physics experiments. In the framework of the LHCb and COMPASS experiments, we have started an R and D programme to assess and to eventually overcome the limits of present technologies. Here, we present the available mirror technologies and discuss the optical and mechanical parameters

  13. Multianode Photo Multiplier Tubes as Photo Detectors for Ring Imaging Cherenkov Detectors

    CERN Document Server

    Muheim, F

    2003-01-01

    The 64-channel Multianode Photo Multiplier (MaPMT) has been evaluated as a candidate for the LHCb Ring Imaging Cherenkov (RICH) photo detectors. We present result from data taken with a 3x3 array of closely packed MaPMTs mounted onto the RICH 1 prototype vessel, exposed to charged particle beams at CERN, and read out at LHC speed. Using a LED light source, we have performed spatial light scans to study the light collection efficiency of the MaPMTs We have also measured the performance of the MaPMTs as a function of the applied high voltage. Different dynode resistor chains have been used to study the tubes at low gains. In addition, we have studied the behaviour of the MaPMT in magnetic fields.

  14. Search for long-lived heavy charged particles using a ring imaging Cherenkov technique at LHCb

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Adeva, B. [Universidad de Santiago de Compostela (Spain); Adinolfi, M. [Bristol Univ. (United Kingdom). H.H. Wills Physics Lab.; and others

    2015-12-15

    A search is performed for heavy long-lived charged particles using 3.0 fb{sup -1} of proton-proton collisions collected at √(s) = 7 and 8 TeV with the LHCb detector. The search is mainly based on the response of the ring imaging Cherenkov detectors to distinguish the heavy, slow-moving particles from muons. No evidence is found for the production of such long-lived states. The results are expressed as limits on the Drell-Yan production of pairs of long-lived particles, with both particles in the LHCb pseudorapidity acceptance, 1.8 < η < 4.9. The mass-dependent cross-section upper limits are in the range 2-4 fb (at 95 % CL) for masses between 14 and 309 GeV/c{sup 2}. (orig.)

  15. Search for long-lived heavy charged particles using a ring imaging Cherenkov technique at LHCb

    Energy Technology Data Exchange (ETDEWEB)

    Aaij, R. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Adeva, B. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain); Adinolfi, M. [H.H. Wills Physics Laboratory, University of Bristol, Bristol (United Kingdom); Affolder, A. [Oliver Lodge Laboratory, University of Liverpool, Liverpool (United Kingdom); Ajaltouni, Z. [Clermont Université, Université Blaise Pascal, CNRS/IN2P3, LPC, Clermont-Ferrand (France); and others

    2015-12-15

    A search is performed for heavy long-lived charged particles using 3.0 fb{sup -1} of proton–proton collisions collected at √s= 7 and 8 TeV with the LHCb detector. The search is mainly based on the response of the ring imaging Cherenkov detectors to distinguish the heavy, slow-moving particles from muons. No evidence is found for the production of such long-lived states. The results are expressed as limits on the Drell–Yan production of pairs of long-lived particles, with both particles in the LHCb pseudorapidity acceptance, 1.8<η<4.9. The mass-dependent cross-section upper limits are in the range 2–4 fb (at 95 % CL) for masses between 14 and 309 GeV /c{sup 2}.

  16. The Cherenkov Telescope Array

    OpenAIRE

    Bigongiari, Ciro

    2016-01-01

    The Cherenkov Telescope Array (CTA) is planned to be the next generation ground based observatory for very high energy (VHE) gamma-ray astronomy. Gamma-rays provide a powerful insight into the non-thermal universe and hopefully a unique probe for new physics. Imaging Cherenkov telescopes have already discovered more than 170 VHE gamma-ray emitters providing plentiful of valuable data and clearly demonstrating the power of this technique. In spite of the impressive results there are indication...

  17. Gamma-Hadron Separation Methods for the VERITAS Array of Four Imaging Atmospheric Cherenkov Telescopes

    CERN Document Server

    Krawczynski, H; Duke, C; Holder, J; Le Bohec, S; Maier, G; Sembroski, G

    2006-01-01

    Ground-based arrays of imaging atmospheric Cherenkov telescopes have emerged as the most sensitive gamma-ray detectors in the energy range of about 100 GeV and above. The strengths of these arrays are a very large effective collection area on the order of 100,000 square meter, combined with excellent single photon angular and energy resolutions. The sensitivity of such detectors is limited by statistical fluctuations in the number of Cosmic Ray initiated air showers that resemble gamma-ray air showers in many ways. In this paper, we study the performance of simple event reconstruction methods when applied to simulated data of the Very Energetic Radiation Imaging Telescope Array System (VERITAS) experiment. We review methods for reconstructing the arrival direction and the energy of the primary photons, and examine means to improve on their performance. For a software threshold energy of 300 GeV (100 GeV), the methods achieve point source angular and energy resolutions of sigma[63%]= 0.1 degree (0.2 degree) an...

  18. All-fiber femtosecond Cherenkov source

    Directory of Open Access Journals (Sweden)

    Tu H.

    2013-03-01

    Full Text Available An all-fiber femtosecond Cherenkov radiation source is demonstrated for the first time, to the best of our knowledge. Using a stable monolithic femtosecond Ybdoped fiber laser as the pump source, and the combination of photonic crystal fibers as the wave-conversion medium, we have generated tunable Cherenkov radiation at visible wavelengths 580 – 630 nm, with pulse duration of sub-160 fs, and the 3 dB spectral bandwidth not exceeding 36 nm. Such femtosecond source can find applications in practical biophotonics such as bio-imaging and microscopy.

  19. All-fiber femtosecond Cherenkov source

    DEFF Research Database (Denmark)

    Liu, Xiaomin; Lægsgaard, Jesper; Møller, Uffe Visbech;

    2013-01-01

    An all-fiber femtosecond Cherenkov radiation source is demonstrated for the first time, to the best of our knowledge. Using a stable monolithic femtosecond Ybdoped fiber laser as the pump source, and the combination of photonic crystal fibers as the wave-conversion medium, we have generated tunable...... Cherenkov radiation at visible wavelengths 580 - 630 nm, with pulse duration of sub-160 fs, and the 3 dB spectral bandwidth not exceeding 36 nm. Such femtosecond source can find applications in practical biophotonics such as bio-imaging and microscopy....

  20. The Ring Imaging Cherenkov detector of the AMS experiment: test beam results with a prototype

    CERN Document Server

    Arruda, Luísa; Goncalves, Patrícia; Pereira, Rui

    2008-01-01

    The Alpha Magnetic Spectrometer (AMS) to be installed on the International Space Station (ISS) will be equipped with a proximity Ring Imaging Cherenkov (RICH) detector for measuring the velocity and electric charge of the charged cosmic particles. This detector will contribute to the high level of redundancy required for AMS as well as to the rejection of albedo particles. Charge separation up to iron and a velocity resolution of the order of 0.1% for singly charged particles are expected. A RICH protoptype consisting of a detection matrix with 96 photomultiplier units, a segment of a conical mirror and samples of the radiator materials was built and its performance was evaluated. Results from the last test beam performed with ion fragments resulting from the collision of a 158 GeV/c/nucleon primary beam of indium ions (CERN SPS) on a lead target are reported. The large amount of collected data allowed to test and characterize different aerogel samples and the sodium fluoride radiator. In addition, the reflec...

  1. A ring imaging Cherenkov counter for the AMS experiment: simulation, prototype and perspective

    International Nuclear Information System (INIS)

    The AMS spectrometer is scheduled to be installed on the International Space Station ISS in 2003. The detector will be equipped with a Ring Imaging Cherenkov Counter (RICH). The report starts with a presentation of the physics goals of AMS and continues with a description of the spectrometer. The RICH detector response and event reconstruction is then described and detailed. The presentation proceeds with a simulation study of cosmic ray nuclei expected with the AMS RICH counter in space. Next, the thesis reports on the research and development of a RICH prototype built and tested in the period 1997-1999 in the Grenoble Institute of Nuclear Science (ISN). The response of the prototype and its calibration are described. Tests have been performed with cosmic rays at ground and ion beam at GSI-Darmstadt. The data analysis of the test campaigns is then presented and compared with simulation results. Finally, a dedicated test of Albedo particle Rejection Power of the RICH detector is reported. (author)

  2. Pixel hybrid photon detectors for the ring imaging Cherenkov detectors of LHCb

    CERN Document Server

    Somerville, L

    2005-01-01

    A Pixel Hybrid Photon Detector (pixel HPD) has been developed for the LHCb Ring Imaging Cherenkov (RICH) detectors. The pixel HPD is a vacuum tube with a multi-alkali photocathode, high-voltage cross- focused electron optics and an anode consisting of a silicon pixel detector bump-bonded to a CMOS readout chip; the readout chip is thus fully encapsulated in the device. The pixel HPD fulfils the stringent requirements for the RICH detectors of LHCb, combining single photon sensitivity, high signal-to-noise ratio and fast readout with an ~8cm diameter active area and an effective pixel size of 2.5mm 2.5mm at the photocathode. The performance and characteristics of two prototype pixel HPDs have been studied in laboratory measurements and in recent beam tests. The results of all measurements agree with expectations and fulfil the LHCb RICH requirements. In readiness for production of the ~500pixel HPDs for the RICH detectors, a test programme was designed and implemented to ensure component quality control at eac...

  3. Tunable femtosecond Cherenkov fiber laser

    DEFF Research Database (Denmark)

    Liu, Xiaomin; Svane, Ask Sebastian; Lægsgaard, Jesper;

    2014-01-01

    We demonstrate electrically-tunable femtosecond Cherenkov fiber laser output at the visible range. Using an all-fiber, self-starting femtosecond Yb-doped fiber laser as the pump source and nonlinear photonic crystal fiber link as the wave-conversion medium, ultrafast, milliwatt-level, tunable...... and spectral isolated Cherenkov radiation at visible wavelengths are reported. Such a femtosecond Cherenkov laser source is promising for practical biophotonics applications....

  4. Measurement of charged hadron spectra at the Z0 with Cherenkov ring imaging

    International Nuclear Information System (INIS)

    This dissertation attempts to probe hadronization, the process by which the fundamental quarks described by quantum chromodynamics produce the jets of hadrons that the author observed in experiments. The measurements are made using e+e- collisions at the SLAC Linear Collider (SLC), operating at the Z0 resonance with the SLC Large Detector (SLD), and the unique capabilities of the SLC/SLD facility are exploited. First, the spectra of charged hadrons (π±, K±, and p/anti p) are measured. This is accomplished with the SLD Cherenkov Ring Imaging Detector (CRID), one of a first generation of devices that have been developed for efficient particle identification over a wide momentum range. The use of the CRID is central to this dissertation, and its design and performance are described in detail here. The measured spectra agree with other measurements at the Z0 and extend the momentum coverage. Next, the excellent spatial resolution of the SLD tracking systems, along with the small and stable beam spots of the SLC, is employed to identify jets produced from heavy b or c quarks and to separate them from the remaining light-quark (uds) jets. This removes the effects of heavy quark fragmentation and decays of heavy-quark hadrons from the study of hadronization. The first measurements of particle spectra in light-quark jets are then presented. Finally, the highly-polarized incident electron beam of the SLC, together with the electroweak asymmetries of the quarks, is exploited to separate quark and antiquark jets. Significant differences in quark-antiquark production of protons and of kaons are observed at high momenta. This signal suggests a leading particle effect, where the particles containing the primary quark of a jet are more likely to populate the high-momentum phase space than are other hadrons

  5. Tests of innovative photon detectors and integrated electronics for the large-area CLAS12 ring-imaging Cherenkov detector

    Energy Technology Data Exchange (ETDEWEB)

    Contalbrigo, Marco [INFN, Ferrara, Italy

    2015-07-01

    A large area ring-imaging Cherenkov detector has been designed to provide clean hadron identification capability in the momentum range from 3 GeV/c to 8 GeV/c for the CLAS12 experiments at the upgraded 12 GeV continuous electron beam accelerator facility of Jefferson Lab. Its aim is to study the 3D nucleon structure in the yet poorly explored valence region by deep-inelastic scattering, and to perform precision measurements in hadron spectroscopy. The adopted solution foresees a novel hybrid optics design based on an aerogel radiator, composite mirrors and a densely packed and highly segmented photon detector. Cherenkov light will either be imaged directly (forward tracks) or after two mirror reflections (large angle tracks). Extensive tests have been performed on Hamamatsu H8500 and novel flat multi-anode photomultipliers under development and on various types of silicon photomultipliers. A large scale prototype based on 28 H8500 MA-PMTs has been realized and tested with few GeV/c hadron beams at the T9 test-beam facility of CERN. In addition a small prototype was used to study the response of customized SiPM matrices within a temperature interval ranging from 25 down to –25 °C. The preliminary results of the individual photon detector tests and of the prototype performance at the test-beams are here reported.

  6. Tests of innovative photon detectors and integrated electronics for the large-area CLAS12 ring-imaging Cherenkov detector

    Energy Technology Data Exchange (ETDEWEB)

    Contalbrigo, M., E-mail: contalbrigo@fe.infn.it

    2015-07-01

    A large area ring-imaging Cherenkov detector has been designed to provide clean hadron identification capability in the momentum range from 3 GeV/c to 8 GeV/c for the CLAS12 experiments at the upgraded 12 GeV continuous electron beam accelerator facility of Jefferson Lab. Its aim is to study the 3D nucleon structure in the yet poorly explored valence region by deep-inelastic scattering, and to perform precision measurements in hadron spectroscopy. The adopted solution foresees a novel hybrid optics design based on an aerogel radiator, composite mirrors and a densely packed and highly segmented photon detector. Cherenkov light will either be imaged directly (forward tracks) or after two mirror reflections (large angle tracks). Extensive tests have been performed on Hamamatsu H8500 and novel flat multi-anode photomultipliers under development and on various types of silicon photomultipliers. A large scale prototype based on 28 H8500 MA-PMTs has been realized and tested with few GeV/c hadron beams at the T9 test-beam facility of CERN. In addition a small prototype was used to study the response of customized SiPM matrices within a temperature interval ranging from 25 down to −25 °C. The preliminary results of the individual photon detector tests and of the prototype performance at the test-beams are here reported.

  7. A new analysis strategy for detection of faint gamma-ray sources with Imaging Atmospheric Cherenkov Telescopes

    CERN Document Server

    Becherini, Yvonne; Marandon, Vincent; Punch, Michael; Pita, Santiago; 10.1016/j.astropartphys.2011.03.005

    2011-01-01

    A new background rejection strategy for gamma-ray astrophysics with stereoscopic Imaging Atmospheric Cherenkov Telescopes (IACT), based on Monte Carlo (MC) simulations and real background data from the H.E.S.S. [High Energy Stereoscopic System, see [1].] experiment, is described. The analysis is based on a multivariate combination of both previously-known and newly-derived discriminant variables using the physical shower properties, as well as its multiple images, for a total of eight variables. Two of these new variables are defined thanks to a new energy evaluation procedure, which is also presented here. The method allows an enhanced sensitivity with the current generation of ground-based Cherenkov telescopes to be achieved, and at the same time its main features of rapidity and flexibility allow an easy generalization to any type of IACT. The robustness against Night Sky Background (NSB) variations of this approach is tested with MC simulated events. The overall consistency of the analysis chain has been ...

  8. TH-C-17A-03: Dynamic Visualization and Dosimetry of IMRT and VMAT Treatment Plans by Video-Rate Imaging of Cherenkov Radiation in Pure Water

    Energy Technology Data Exchange (ETDEWEB)

    Glaser, A; Andreozzi, J; Davis, S [Thayer School of Engineering, Dartmouth College, NH (United States); Zhang, R [Department of Physics and Astronomy, Dartmouth College, Hanover, NH (United States); Fox, C; Gladstone, D [Dartmouth Hitchcock Medical Center, Lebanon, NH (Lebanon); Pogue, B [Thayer School of Engineering, Dartmouth College, NH (United States); Department of Physics and Astronomy, Dartmouth College, Hanover, NH (United States)

    2014-06-15

    Purpose: A novel optical dosimetry technique for the QA and verification of intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) radiotherapy plans was investigated for the first time by capturing images of the induced Cherenkov radiation in water. Methods: An intensified CCD camera (ICCD) was used to acquire a two-dimensional (2D) projection image of the Cherenkov radiation induced by IMRT and VMAT plans, based on the Task Group 119 C-Shape geometry. Plans were generated using the Varian Eclipse treatment planning system (TPS) and delivered using 6 MV x-rays from a Varian TrueBeam Linear Accelerator (Linac) incident on a water tank. The ICCD acquisition was gated to the Linac, operated for single pulse imaging, and binned to a resolution of 512×512 pixels. The resulting videos were analyzed temporally for regions of interest (ROI) covering the planning target volume (PTV) and organ at risk (OAR) and summed to obtain an overall light distribution, which was compared to the expected dose distribution from the TPS using a gammaindex analysis. Results: The chosen camera settings resulted in data at 23.5 frames per second. Temporal intensity plots of the PTV and OAR ROIs confirmed the preferential delivery of dose to the PTV versus the OAR, and the gamma analysis yielded 95.2% and 95.6% agreement between the light distribution and expected TPS dose distribution based upon a 3% / 3 mm dose difference and distance-to-agreement criterion for the IMRT and VMAT plans respectively. Conclusion: The results from this initial study demonstrate the first documented use of Cherenkov radiation for optical dosimetry of dynamic IMRT and VMAT treatment plans. The proposed modality has several potential advantages over alternative methods including the real-time nature of the acquisition, and upon future refinement may prove to be a robust and novel dosimetry method with both research and clinical applications. NIH R01CA109558 and R21EB017559.

  9. TH-C-17A-03: Dynamic Visualization and Dosimetry of IMRT and VMAT Treatment Plans by Video-Rate Imaging of Cherenkov Radiation in Pure Water

    International Nuclear Information System (INIS)

    Purpose: A novel optical dosimetry technique for the QA and verification of intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) radiotherapy plans was investigated for the first time by capturing images of the induced Cherenkov radiation in water. Methods: An intensified CCD camera (ICCD) was used to acquire a two-dimensional (2D) projection image of the Cherenkov radiation induced by IMRT and VMAT plans, based on the Task Group 119 C-Shape geometry. Plans were generated using the Varian Eclipse treatment planning system (TPS) and delivered using 6 MV x-rays from a Varian TrueBeam Linear Accelerator (Linac) incident on a water tank. The ICCD acquisition was gated to the Linac, operated for single pulse imaging, and binned to a resolution of 512×512 pixels. The resulting videos were analyzed temporally for regions of interest (ROI) covering the planning target volume (PTV) and organ at risk (OAR) and summed to obtain an overall light distribution, which was compared to the expected dose distribution from the TPS using a gammaindex analysis. Results: The chosen camera settings resulted in data at 23.5 frames per second. Temporal intensity plots of the PTV and OAR ROIs confirmed the preferential delivery of dose to the PTV versus the OAR, and the gamma analysis yielded 95.2% and 95.6% agreement between the light distribution and expected TPS dose distribution based upon a 3% / 3 mm dose difference and distance-to-agreement criterion for the IMRT and VMAT plans respectively. Conclusion: The results from this initial study demonstrate the first documented use of Cherenkov radiation for optical dosimetry of dynamic IMRT and VMAT treatment plans. The proposed modality has several potential advantages over alternative methods including the real-time nature of the acquisition, and upon future refinement may prove to be a robust and novel dosimetry method with both research and clinical applications. NIH R01CA109558 and R21EB017559

  10. Strange meson spectroscopy in K[omega] and K[phi] at 11 GeV/c and Cherenkov ring imaging at SLD

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Youngjoon.

    1993-01-01

    This thesis consists of two independent parts; development of Cherenkov Ring Imaging Detector (CRID) system and analysis of high-statistics data of strange meson reactions from the LASS spectrometer. Part 1: The CRID system is devoted to charged particle identification in the SLAC Large Detector (SLD) to study e[sup +]e[sup [minus

  11. An astroclimatological study of candidate sites to host an imaging atmospheric Cherenkov telescope in Romania

    CERN Document Server

    Radu, A A; Curtef, V; Felea, D; Hasegan, D; Lucaschi, B; Manea, A; Popa, V; Ralita, I

    2011-01-01

    We come out in this paper with an astroclimatological study of meteorological data on relative humidity, dew point temperature, air temperature, wind speed, barometric air pressure, and sky cloudiness recorded at four Romanian locations (Baisoara, Rosia Montana, Semenic, Ceahlau) and Nordic Optical Telescope (NOT) located at Observatorio del Roque de Los Muchachos, in the Canary Islands. Long term trends of microclimates have been compared in order to identify the site-to-site variations. We have performed this analysis as part of a site testing campaign aimed at finding the best location for the establishment of a small Cherenkov telescope in Romania. The conditions at the Romanian sites have been compared to those of the Canary Islands considered as a reference. A statistical approach has been used for data analysis. Monthly and annual samples have been extracted from series of raw data for nighttime, daytime and entire day intervals. Percentage distributions of meteorological parameters, whose values excee...

  12. Strange meson spectroscopy in Kω and Kφ at 11 GeV/c and Cherenkov ring imaging at SLD

    International Nuclear Information System (INIS)

    This thesis consists of two independent parts; development of Cherenkov Ring Imaging Detector (CRID) system and analysis of high-statistics data of strange meson reactions from the LASS spectrometer. Part 1: The CRID system is devoted to charged particle identification in the SLAC Large Detector (SLD) to study e+e- collisions at √s = mZ0. By measuring the angles of emission of the Cherenkov photons inside liquid and gaseous radiators, π/K/p separation will be achieved up to ∼30 GeV/c. The signals from CRID are read in three coordinates, one of which is measured by charge-division technique. To obtain a ∼1% spatial resolution in the charge-division, low-noise CRID preamplifier prototypes were developed and tested resulting in 5 gain. To help ensure the long-term stability of CRID operation at high efficiency, a comprehensive monitoring and control system was developed. Part 2: Results from the partial wave analysis of strange meson final states in the reactions K-p → K-ωp and K-p → bar K0φn are presented. The analyses are based on data from a 4.1 event/nb exposure of the LASS spectrometer in K-p interactions at 11 GeV/c. The data sample of K-ωp final state contains ∼105 events. From the partial wave analysis, resonance structures of JP = 2-, 3- and 2+ amplitudes are observed in the Kω system. The analysis of 2- amplitudes provides an evidence for two strange meson states in the mass region around 1.75 GeV/c2. The appropriate branching fractions are calculated and compared with the SU(3) predictions. The partial wave analysis of bar K0φ system favors JP = 1- and 2+ states in the 1.9--2.0 GeV/c2 region

  13. 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.

  14. Study of timing performance of silicon photomultiplier and application for a Cherenkov detector

    Science.gov (United States)

    Ahmed, G. S. M.; Bühler, P.; Marton, J.; Suzuki, K.

    2011-02-01

    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 3×3 mm 2 MPPCs S10362-33-100C from Hamamatsu Photonics as photo-detectors. The MPPC sensors were operated with Peltier cooling to minimize thermal noise and to avoid gain drifts. The test measurements at the DA Φ 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.

  15. Particle Identification in Cherenkov Detectors using Convolutional Neural Networks

    CERN Document Server

    Theodore, Tomalty

    2016-01-01

    Cherenkov detectors are used for charged particle identification. When a charged particle moves through a medium faster than light can propagate in that medium, Cherenkov radiation is released in the shape of a cone in the direction of movement. The interior of the Cherenkov detector is instrumented with PMTs to detect this Cherenkov light. Particles, then, can be identified by the shapes of the images on the detector walls.

  16. The cross-talk problem in SiPMs and their use as light sensors for imaging atmospheric Cherenkov telescopes

    International Nuclear Information System (INIS)

    One of the major drawbacks of a SiPM is due to the so-called cross-talk effect. Often, one single photon in a chain reaction can generate more photons and thus can fire more than one micro-cell of a SiPM. This can be considered as a noise in the signal multiplication process and this degrades the signal/noise ratio. In self-trigger schemes this noise can be so high that it can make operating them difficult at low threshold settings. For the past few years, we have dwelt on this effect aiming to suppress it at the design stage. One can use (a) trenches around the micro-cells for suppressing the direct photon 'communication' channel and (b) the so-called double p-n junction for suppressing photon-induced charge 'communication' in neighbor pixels. The low cross-talk is mandatory, for example, for producing SiPM-based light sensor modules for the Imaging Atmospheric Cherenkov Technique projects for ground-based gamma-ray astrophysics. We produced and tested a few modules consisting of 4 SiPMs, each with a size of 5 mmx5 mm of custom production type. We report here on the main parameters of these units.

  17. All-fiber femtosecond Cherenkov radiation source

    DEFF Research Database (Denmark)

    Liu, Xiaomin; Lægsgaard, Jesper; Møller, Uffe;

    2012-01-01

    -conversion medium, we demonstrate milliwatt-level, stable, and tunable Cherenkov radiation at visible wavelengths 580–630 nm, with pulse duration of sub-160-fs, and the 3 dB spectral bandwidth not exceeding 36 nm. Such an all-fiber Cherenkov radiation source is promising for practical applications in biophotonics...

  18. The Non-Imaging CHErenkov Array (NICHE): A TA/TALE Extension to Measure the Flux and Composition of Very-High Energy Cosmic Rays

    CERN Document Server

    Krizmanic, John

    2013-01-01

    Co-sited with TA/TALE, the Non-Imaging CHErenkov Array (NICHE) will measure the flux and nuclear composition of cosmic rays from below 10^16 eV to 10^18 eV in its initial deployment. Furthermore, the low-energy threshold can be significantly decreased below the cosmic ray knee via counter redeployment or by including additional counters. NICHE uses easily deployable detectors to measure the amplitude and time-spread of the air-shower Cherenkov signal to achieve an event-by-event measurement of Xmax and energy, each with excellent resolution. NICHE will have sufficient area and angular acceptance to have significant overlap with the TA/TALE detectors to allow for energy cross-calibration. Simulated NICHE performance has shown that the array has the ability to distinguish between several different composition models as well as measure the end of Galactic cosmic ray spectrum.

  19. New large aperture, hybrid photo-detector and photo multiplier tube for a gigantic water Cherenkov ring imaging detector

    Energy Technology Data Exchange (ETDEWEB)

    Hirota, Seiko, E-mail: s_hirota@scphys.kyoto-u.ac.jp [Kyoto University, Department of Physics (Japan); Nishimura, Yasuhiro [University of Tokyo, ICRR (Japan); Suda, Yusuke [University of Tokyo, Department of Physics (Japan); Okajima, Yuji [Tokyo Institute of Technology, Department of Physics (Japan); Shiozawa, Masato; Nakayama, Shoei; Tanaka, Hidekazu; Hayato, Yoshinari; Ikeda, Motoyasu; Nakahata, Masayuki [University of Tokyo, ICRR (Japan); Yokoyama, Masashi; Aihara, Hiroaki [University of Tokyo, Department of Physics (Japan); Ichikawa, Atsuko; Minamino, Akihiro; Huang, Kunxian; Nakaya, Tsuyoshi [Kyoto University, Department of Physics (Japan); Kawai, Yoshihiko; Suzuki, Masatoshi; Ohmura, Takayuki [Hamamatsu Photonics K.K. (Japan)

    2014-12-01

    We are developing a 20-in. aperture high quantum efficiency photo-multiplier tube (PMT) and a hybrid photo-detector (HPD) for Hyper-Kamiokande which is a next generation underground large water Cherenkov detector. We have measured prototypes of 20-in. PMT with a high quantum efficiency photocathode, 30% at 400 nm, and 8-in. HPDs with a normal quantum efficiency photocathode, 22% at 400 nm, in a 200-ton water tank and checked their performance. The PMTs have a 2.7 ns (sigma) timing resolution and 43% (sigma) charge resolution for single photo-electron. Compared to PMTs, HPDs show a better performance with a 1.7 ns timing resolution and 32. - Highlights: • For Hyper-Kamiokande, a large aperture hybrid photo-detector (HPD) has been developed. • The application of high quantum efficiency photo-cathode has been also studied. • The 8-in. HPDs and 20-in. HQE PMTs have been tested in a 200-ton water tank from summer in 2013. • The HPDs show better charge and timing resolution, and lower dark rate than PMTs. • The HQE PMTs have not been stabilized yet and show higher dark rate than normal PMTs.

  20. Stability Property of Numerical Cherenkov Radiation and its Application to Relativistic Shock Simulations

    CERN Document Server

    Ikeya, Naoki

    2014-01-01

    We studied the stability property of numerical Cherenkov radiation in relativistic plasma flows employing particle-in-cell simulations. Using the implicit finite-difference time-domain method to solve Maxwell equations, we found that nonphysical instability was greatly inhibited with a CFL number of 1.0. The present result contrasts with recently reported results (Vay et al., 2011; Godfrey & Vay,2013) in which magical CFL numbers in the range 0.5-0.7 were obtained with explicit field solvers. In addition, we found employing higher-order shape functions and an optimal implicitness factor further suppressed long-wavelength modes of the instability. The findings allowed the examination of the long-term evolution of a relativistic collisionless shock without the generation of nonphysical wave excitations in the upstream. This achievement will allow us to investigate particle accelerations in relativistic shocks associated with, for example, gamma-ray bursts.

  1. Gamma/hadron segregation for a ground based imaging atmospheric Cherenkov telescope using machine learning methods: Random Forest leads

    International Nuclear Information System (INIS)

    A detailed case study of γ-hadron segregation for a ground based atmospheric Cherenkov telescope is presented. We have evaluated and compared various supervised machine learning methods such as the Random Forest method, Artificial Neural Network, Linear Discriminant method, Naive Bayes Classifiers, Support Vector Machines as well as the conventional dynamic supercut method by simulating triggering events with the Monte Carlo method and applied the results to a Cherenkov telescope. It is demonstrated that the Random Forest method is the most sensitive machine learning method for γ-hadron segregation. (research papers)

  2. Development of a 144-channel Hybrid Avalanche Photo-Detector for Belle II ring-imaging Cherenkov counter with an aerogel radiator

    Energy Technology Data Exchange (ETDEWEB)

    Nishida, S., E-mail: shohei.nishida@kek.jp [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Adachi, I. [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Hamada, N. [Toho University, Funabashi (Japan); Hara, K. [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Iijima, T. [Nagoya University, Nagoya (Japan); Iwata, S.; Kakuno, H. [Tokyo Metropolitan University, Hachioji (Japan); Kawai, H. [Chiba University, Chiba (Japan); Korpar, S.; Krizan, P. [Jozef Stefan Institute, Ljubljana (Slovenia); Ogawa, S. [Toho University, Funabashi (Japan); Pestotnik, R.; Ŝantelj, L.; Seljak, A. [Jozef Stefan Institute, Ljubljana (Slovenia); Sumiyoshi, T. [Tokyo Metropolitan University, Hachioji (Japan); Tabata, M. [Chiba University, Chiba (Japan); Tahirovic, E. [Jozef Stefan Institute, Ljubljana (Slovenia); Yoshida, K. [Tokyo Metropolitan University, Hachioji (Japan); Yusa, Y. [Niigata University, Niigata (Japan)

    2015-07-01

    The Belle II detector, a follow up of the very successful Belle experiment, is under construction at the SuperKEKB electron–positron collider at KEK in Japan. For the PID system in the forward region of the spectrometer, a proximity-focusing ring-imaging Cherenkov counter with an aerogel radiator is being developed. For the position sensitive photon sensor, a 144-channel Hybrid Avalanche Photo-Detector has been developed with Hamamatsu Photonics K.K. In this report, we describe the specification of the Hybrid Avalanche Photo-Detector and the status of the mass production.

  3. Development of a 144-channel Hybrid Avalanche Photo-Detector for Belle II ring-imaging Cherenkov counter with an aerogel radiator

    International Nuclear Information System (INIS)

    The Belle II detector, a follow up of the very successful Belle experiment, is under construction at the SuperKEKB electron–positron collider at KEK in Japan. For the PID system in the forward region of the spectrometer, a proximity-focusing ring-imaging Cherenkov counter with an aerogel radiator is being developed. For the position sensitive photon sensor, a 144-channel Hybrid Avalanche Photo-Detector has been developed with Hamamatsu Photonics K.K. In this report, we describe the specification of the Hybrid Avalanche Photo-Detector and the status of the mass production

  4. The Cherenkov Telescope Array

    CERN Document Server

    Bigongiari, Ciro

    2016-01-01

    The Cherenkov Telescope Array (CTA) is planned to be the next generation ground based observatory for very high energy (VHE) gamma-ray astronomy. Gamma-rays provide a powerful insight into the non-thermal universe and hopefully a unique probe for new physics. Imaging Cherenkov telescopes have already discovered more than 170 VHE gamma-ray emitters providing plentiful of valuable data and clearly demonstrating the power of this technique. In spite of the impressive results there are indications that the known sources represent only the tip of the iceberg. A major step in sensitivity is needed to increase the number of detected sources, observe short time-scale variability and improve morphological studies of extended sources. An extended energy coverage is advisable to observe far-away extragalactic objects and improve spectral analysis. CTA aims to increase the sensitivity by an order of magnitude compared to current facilities, to extend the accessible gamma-ray energies from a few tens of GeV to a hundred o...

  5. Search for long-lived heavy charged particles using a ring imaging Cherenkov technique at LHCb

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; d'Argent, Philippe; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Birnkraut, Alex; Bizzeti, Andrea; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casanova Mohr, Raimon; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cavallero, Giovanni; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Di Ruscio, Francesco; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Gazzoni, Giulio; Geraci, Angelo; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Gianì, Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Humair, Thibaud; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Kenzie, Matthew; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Machikhiliyan, Irina V; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; McSkelly, Ben; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Mitzel, Dominik Stefan; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Janine; Müller, Katharina; Müller, Vanessa; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Osorio Rodrigues, Bruno; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Aranzazu; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Poikela, Tuomas; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skillicorn, Ian; Skwarnicki, Tomasz; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Sterpka, Christopher Francis; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szumlak, Tomasz; T'Jampens, Stephane; Tekampe, Tobias; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Todd, Jacob; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ubeda Garcia, Mario; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wiedner, Dirk; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang

    2015-01-01

    A search is performed for heavy long-lived charged particles using 3.0 fb$^{-1}$ of pp collisions collected at $\\sqrt{s}$= 7 and 8 TeV with the LHCb detector. The search is mainly based on the response of the ring imaging Cherenkovdetectors to distinguish the heavy, slow-moving particles from muons. No evidence is found for the production of such long-lived states. The results are expressed as limits on the Drell-Yan production of pairs of long-lived particles, with both particles in the LHCb pseudorapidity acceptance, $1.8 < \\eta < 4.9$. The mass-dependent cross-section upper limits are in the range 2-4 fb (at 95\\% CL) for masses between 124 and 309 GeV/c$^2$.

  6. All-fiber femtosecond Cherenkov radiation source.

    Science.gov (United States)

    Liu, Xiaomin; Lægsgaard, Jesper; Møller, Uffe; Tu, Haohua; Boppart, Stephen A; Turchinovich, Dmitry

    2012-07-01

    An all-fiber femtosecond source of spectrally isolated Cherenkov radiation is reported, to the best of our knowledge, for the first time. Using a monolithic, self-starting femtosecond Yb-doped fiber laser as the pump source and the combination of photonic crystal fibers as the wave-conversion medium, we demonstrate milliwatt-level, stable, and tunable Cherenkov radiation at visible wavelengths 580-630 nm, with pulse duration of sub-160-fs, and the 3 dB spectral bandwidth not exceeding 36 nm. Such an all-fiber Cherenkov radiation source is promising for practical applications in biophotonics such as bioimaging and microscopy. PMID:22743523

  7. The TORCH PMT: a close packing, multi-anode, long life MCP-PMT for Cherenkov applications

    International Nuclear Information System (INIS)

    Photek (U.K.) and the TORCH collaboration are undertaking a three year development program to produce a novel square MCP-PMT for single photon detection. The TORCH detector aims to provide particle identification in the 2–10 GeV/c momentum range, using a Time-of-Flight method based on Cherenkov light. It is a stand-alone R and D project with possible application in LHCb, and has been proposed for the LHCb Upgrade. The Microchannel Plate (MCP) detector will provide a single photon timing accuracy of 40 ps, and its development will include the following properties: (i) Long lifetime up to at least 5 C/cm2; (ii) Multi-anode output with a spatial resolution of 6 mm and 0.4 mm respectively in the horizontal and vertical directions, incorporating a novel charge-sharing technique; (iii) Close packing on two opposing sides with an active area fill factor of 88% in the horizontal direction. Results from simulations modelling the MCP detector performance factoring in the pulse height variation from the detector, NINO threshold levels and potential charge sharing techniques that enhance the position resolution beyond the physical pitch of the pixel layout will be discussed. Also, a novel method of coupling the MCP-PMT output pads using Anisotropic Conductive Film (ACF) will be described. This minimises parasitic input capacitance by allowing very close proximity between the frontend electronics and the MCP detector

  8. A Monte Carlo template-based analysis for very high definition imaging atmospheric Cherenkov telescopes as applied to the VERITAS telescope array

    CERN Document Server

    ,

    2015-01-01

    We present a sophisticated likelihood reconstruction algorithm for shower-image analysis of imaging Cherenkov telescopes. The reconstruction algorithm is based on the comparison of the camera pixel amplitudes with the predictions from a Monte Carlo based model. Shower parameters are determined by a maximisation of a likelihood function. Maximisation of the likelihood as a function of shower fit parameters is performed using a numerical non-linear optimisation technique. A related reconstruction technique has already been developed by the CAT and the H.E.S.S. experiments, and provides a more precise direction and energy reconstruction of the photon induced shower compared to the second moment of the camera image analysis. Examples are shown of the performance of the analysis on simulated gamma-ray data from the VERITAS array.

  9. Qualification and Testing of a Large Hot Slumped Secondary Mirror for Schwarzschild-Couder Imaging Air Cherenkov Telescopes

    Science.gov (United States)

    Rodeghiero, G.; Giro, E.; Canestrari, R.; Pernechele, C.; Sironi, G.; Pareschi, G.; Lessio, L.; Conconi, P.

    2016-05-01

    Dual-mirror Schwarzschild-Couder (SC) telescopes are based on highly aspherical optics, and they represent a novel design in the world of very high energy astrophysics. This work addresses the realization and the qualification of the secondary mirror for an SC telescope, named ASTRI, developed in the context of the Cherenkov Telescope Array Observatory. The discussion surveys the overall development from the early design concept to the final acceptance optical tests.

  10. The Non-Imaging CHErenkov Array (NICHE): A TA/TALE extension to measure the flux and composition of Very-High Energy Cosmic Rays

    Science.gov (United States)

    Bergman, Douglas; Krizmanic, John; Sokolsky, Pierre

    2013-04-01

    Co-sited with TA/TALE, the Non-Imaging CHErenkov Array (NICHE) will measure the flux and nuclear composition of cosmic rays from below 10^16 eV to over 10^18 eV in its initial deployment. Furthermore, the low-energy reach can be lowered below the cosmic ray knee via counter redeployment or additional counters. NICHE uses easily deployable detectors to measure the amplitude and time-spread of the air-shower Cherenkov signal to achieve an event-by-event measurement of Xmax and energy, each with excellent resolution. NICHE will have sufficient area and angular acceptance to have significant overlap with the TA/TALE detectors to allow for energy cross-calibration. Simulated NICHE performance has shown that the array has the ability to distinguish between several different composition models as well as measure the end of Galactic cosmic ray spectrum. In this talk, the NICHE design, array performance, and status will be discussed as well as NICHE's ability to measure the cosmic ray nuclear composition as a function of energy.

  11. Searches for dark matter self-annihilation signals from dwarf spheroidal galaxies and the Fornax galaxy cluster with imaging air Cherenkov telescopes

    International Nuclear Information System (INIS)

    Many astronomical observations indicate that dark matter pervades the universe and dominates the formation and dynamics of cosmic structures. Weakly interacting massive particles (WIMPs) with masses in the GeV to TeV range form a popular class of dark matter candidates. WIMP self-annihilation may lead to the production of γ-rays in the very high energy regime above 100 GeV, which is observable with imaging air Cherenkov telescopes (IACTs). For this thesis, observations of dwarf spheroidal galaxies (dSph) and the Fornax galaxy cluster with the Cherenkov telescope systems H.E.S.S., MAGIC and VERITAS were used to search for γ-ray signals of dark matter annihilations. The work consists of two parts: First, a likelihood-based statistical technique was introduced to combine published results of dSph observations with the different IACTs. The technique also accounts for uncertainties on the ''J factors'', which quantify the dark matter content of the dwarf galaxies. Secondly, H.E.S.S. observations of the Fornax cluster were analyzed. In this case, a collection of dark matter halo models was used for the J factor computation. In addition, possible signal enhancements from halo substructures were considered. None of the searches yielded a significant γ-ray signal. Therefore, the results were used to place upper limits on the thermally averaged dark matter self-annihilation cross-section left angle σν right angle. Different models for the final state of the annihilation process were considered. The cross-section limits range from left angle σν right angle UL∝10-19 cm3s-1 to left angle σν right angle UL∝10-25 cm3s-1 for dark matter particles masses between 100 GeV and 100 TeV. Some of the diverse model uncertainties causing this wide range of left angle σν right angle UL values were analyzed.

  12. Bokeh Mirror Alignment for Cherenkov Telescopes

    CERN Document Server

    Ahnen, M L; Balbo, M; Bergmann, M; Biland, A; Blank, M; Bretz, T; Bruegge, K A; Buss, J; Domke, M; Dorner, D; Einecke, S; Hempfling, C; Hildebrand, D; Hughes, G; Lustermann, W; Mannheim, K; Mueller, S A; Neise, D; Neronov, A; Noethe, M; Overkemping, A -K; Paravac, A; Pauss, F; Rhode, W; Shukla, A; Temme, F; Thaele, J; Toscano, S; Vogler, P; Walter, R; Wilbert, A

    2016-01-01

    Imaging Atmospheric Cherenkov Telescopes (IACTs) need imaging optics with large apertures and high image intensities to map the faint Cherenkov light emitted from cosmic ray air showers onto their image sensors. Segmented reflectors fulfill these needs, and composed from mass production mirror facets they are inexpensive and lightweight. However, as the overall image is a superposition of the individual facet images, alignment remains a challenge. Here we present a simple, yet extendable method, to align a segmented reflector using its Bokeh. Bokeh alignment does not need a star or good weather nights but can be done even during daytime. Bokeh alignment optimizes the facet orientations by comparing the segmented reflectors Bokeh to a predefined template. The optimal Bokeh template is highly constricted by the reflector's aperture and is easy accessible. The Bokeh is observed using the out of focus image of a near by point like light source in a distance of about 10 focal lengths. We introduce Bokeh alignment ...

  13. An Experiment to Demonstrate Cherenkov / Scintillation Signal Separation

    CERN Document Server

    Caravaca, J; Land, B J; Wallig, J; Yeh, M; Gann, G D Orebi

    2016-01-01

    The ability to separately identify the Cherenkov and scintillation light components produced in scintillating mediums holds the potential for a major breakthrough in neutrino detection technology, allowing development of a large, low-threshold, directional detector with a broad physics program. The CHESS (CHErenkov / Scintillation Separation) experiment employs an innovative detector design with an array of small, fast photomultiplier tubes and state-of-the-art electronics to demonstrate the reconstruction of a Cherenkov ring in a scintillating medium based on photon hit time and detected photoelectron density. This paper describes the physical properties and calibration of CHESS along with first results. The ability to reconstruct Cherenkov rings is demonstrated in a water target, and a time precision of 338 +/- 12 ps FWHM is achieved. Monte Carlo based predictions for the ring imaging sensitivity with a liquid scintillator target predict an efficiency for identifying Cherenkov hits of 94 +/- 1% and 81 +/- 1...

  14. Optical and radiographical characterization of silica aerogel for Cherenkov radiator

    CERN Document Server

    Tabata, Makoto; Hatakeyama, Yoshikiyo; Kawai, Hideyuki; Morita, Takeshi; Nishikawa, Keiko

    2012-01-01

    We present optical and X-ray radiographical characterization of silica aerogels with refractive index from 1.05 to 1.07 for a Cherenkov radiator. A novel pin-drying method enables us to produce highly transparent hydrophobic aerogels with high refractive index by shrinking wet-gels. In order to investigate the uniformity in the density (i.e., refractive index) of an individual aerogel monolith, we use the laser Fraunhofer method, an X-ray absorption technique, and Cherenkov imaging by a ring imaging Cherenkov detector in a beam test. We observed an increase in density at the edge of the aerogel tiles, produced by pin-drying.

  15. Upgrading and testing the 3D reconstruction of gamma-ray air showers as observed with an array of Imaging Atmospheric Cherenkov telescopes

    CERN Document Server

    Naumann-Godó, M; Degrange, B

    2009-01-01

    Stereoscopic arrays of Imaging Atmospheric Cherenkov Telescopes allow to reconstruct gamma-ray-induced showers in 3 dimensions, which offers several advantages: direct access to the shower parameters in space and straightforward calorimetric measurement of the incident energy. In addition, correlations between the different images of the same shower are taken into account. An analysis method based on a simple 3D-model of electromagnetic showers was recently implemented in the framework of the H.E.S.S. experiment. In the present article, the method is completed by an additional quality criterion, which reduces the background contamination by a factor of about 2 in the case of extended sources, while keeping gamma-ray efficiency at a high level. On the other hand, the dramatic flares of the blazar PKS 2155-304 in July 2006, which provided H.E.S.S. data with an almost pure gamma-ray sample, offered the unique opportunity of a precision test of the 3D-reconstruction method as well as of the H.E.S.S. simulations u...

  16. All-fiber femtosecond Cherenkov source

    OpenAIRE

    Tu H.; Møller U.; Lægsgaard J.; Liu X.; Boppart S. A.; Turchinovich D.

    2013-01-01

    An all-fiber femtosecond Cherenkov radiation source is demonstrated for the first time, to the best of our knowledge. Using a stable monolithic femtosecond Ybdoped fiber laser as the pump source, and the combination of photonic crystal fibers as the wave-conversion medium, we have generated tunable Cherenkov radiation at visible wavelengths 580 – 630 nm, with pulse duration of sub-160 fs, and the 3 dB spectral bandwidth not exceeding 36 nm. Such femtosecond source can find applications in pra...

  17. Strange meson spectroscopy in K{omega} and K{phi} at 11 GeV/c and Cherenkov ring imaging at SLD

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Youngjoon

    1993-01-01

    This thesis consists of two independent parts; development of Cherenkov Ring Imaging Detector (CRID) system and analysis of high-statistics data of strange meson reactions from the LASS spectrometer. Part 1: The CRID system is devoted to charged particle identification in the SLAC Large Detector (SLD) to study e{sup +}e{sup {minus}} collisions at {radical}s = m{sub Z{sup 0}}. By measuring the angles of emission of the Cherenkov photons inside liquid and gaseous radiators, {pi}/K/p separation will be achieved up to {approximately}30 GeV/c. The signals from CRID are read in three coordinates, one of which is measured by charge-division technique. To obtain a {approximately}1% spatial resolution in the charge-division, low-noise CRID preamplifier prototypes were developed and tested resulting in <1000 electrons noise for an average photoelectron signal with 2 {times} 10{sup 5} gain. To help ensure the long-term stability of CRID operation at high efficiency, a comprehensive monitoring and control system was developed. Part 2: Results from the partial wave analysis of strange meson final states in the reactions K{sup {minus}}p {yields} K{sup {minus}}{omega}p and K{sup {minus}}p {yields} {bar K}{sup 0}{phi}n are presented. The analyses are based on data from a 4.1 event/nb exposure of the LASS spectrometer in K{sup {minus}}p interactions at 11 GeV/c. The data sample of K{sup {minus}}{omega}p final state contains {approximately}10{sup 5} events. From the partial wave analysis, resonance structures of J{sup P} = 2{sup {minus}}, 3{sup {minus}} and 2{sup +} amplitudes are observed in the K{omega} system. The analysis of 2{sup {minus}} amplitudes provides an evidence for two strange meson states in the mass region around 1.75 GeV/c{sup 2}. The appropriate branching fractions are calculated and compared with the SU(3) predictions. The partial wave analysis of {bar K}{sup 0}{phi} system favors J{sup P} = 1{sup {minus}} and 2{sup +} states in the 1.9--2.0 GeV/c{sup 2} region.

  18. The upgraded MAGIC Cherenkov telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Tescaro, D., E-mail: dtescaro@iac.es [Instituto de Astrofísica de Canarias (IAC), E-38205 La Laguna, Tenerife (Spain); Universidad de La Laguna (ULL), Dept. Astrofísica, E-38206 La Laguna, Tenerife (Spain)

    2014-12-01

    The MAGIC Cherenkov telescopes underwent a major upgrade in 2011 and 2012. A new 1039-pixel camera and a larger area digital trigger system were installed in MAGIC-I, making it essentially identical to the newer MAGIC-II telescope. The readout systems of both telescopes were also upgraded, with fully programmable receiver boards and DRS4-chip-based digitization systems. The upgrade eased the operation and maintenance of the telescopes and also improved significantly their performance. The system has now an integral sensitivity as good as 0.6% of the Crab Nebula flux (for E>400GeV), with an effective analysis threshold at 70 GeV. This allows MAGIC to secure one of the leading roles among the current major ground-based Imaging Atmospheric Cherenkov telescopes for the next 5–10 years. - Highlights: • In 2011 and 2012 the MAGIC telescopes underwent a two-stage major upgrade. • The new camera of MAGIC-I allows us to exploit a 1.4 larger trigger area. • The novel DRS4-based readout systems allow a cost-effective ultra-fast digitization. • The upgrade greatly improved the maintainability of the system. • MAGIC has now an optimal integral sensitivity of 0.6% of the Crab Nebula flux.

  19. Analogue Sum ASIC for L1 Trigger Decision in Cherenkov Telescope Cameras

    CERN Document Server

    Barrio, Joan Abel; Boix, Joan; Delagnes, Eric; Delgado, Carlos; Coromina, Lluis Freixas; Gascon, David; Guilloux, Fabrice; Coto, Ruben Lopez; Martinez, Gustavo; Sanuy, Andreu; Tejedor, Luis Angel

    2014-01-01

    The Cherenkov Telescope Array (CTA) project aims to build the largest ground-based gamma-ray observatory based on an array of Imaging Atmospheric Cherenkov Telescopes (IACTs). The CTA will implement a multi-level trigger system to distinguish between gamma ray-like induced showers and background images induced by night sky background (NSB) light. The trigger system is based on coincident detections among pixels (level 0 trigger), clusters of pixels (level 1) or telescopes. In this article, the first version of the application specific integrated circuit (ASIC) for Level 1 trigger system is presented, capable of working with different Level 0 strategies and different trigger region sizes. In addition, it complies with all the requirements specified by the CTA project, specially the most critical ones as regards noise, bandwidth, dynamic range and power consumption. All these features make the presented system very suitable for use in the CTA cameras and improve the features of discrete components prototypes of...

  20. Statistical properties of Cherenkov and quasi-Cherenkov superradiance

    CERN Document Server

    Anishchenko, S V

    2016-01-01

    We consider the effects of shot noise and particle energy spread on statistical properties of Cherenkov and quasi-Cherenkov superradiance emitted by a relativistic electron beam. In the absence of energy spread, we have found the root-mean-square deviations of both peak radiated power and instability growth time as a function of the number of particles. It is shown that energy spread can lead to a sharp drop in the radiated power of Cherenkov and quasi-Cherenkov superradiance at high currents.

  1. ROBAST: Development of a Non-Sequential Ray-Tracing Simulation Library and its Applications in the Cherenkov Telescope Array

    CERN Document Server

    ,

    2015-01-01

    We have developed a non-sequential ray-tracing simulation library, ROot-BAsed Simulator for ray Tracing (ROBAST), which is aimed for wide use in optical simulations of cosmic-ray (CR) and gamma-ray telescopes. The library is written in C++ and fully utilizes the geometry library of the ROOT analysis framework. Despite the importance of optics simulations in CR experiments, no open-source software for ray-tracing simulations that can be widely used existed. To reduce the unnecessary effort demanded when different research groups develop multiple ray-tracing simulators, we have successfully used ROBAST for many years to perform optics simulations for the Cherenkov Telescope Array (CTA). Among the proposed telescope designs for CTA, ROBAST is currently being used for three telescopes: a Schwarzschild--Couder telescope, one of the Schwarzschild--Couder small-sized telescopes, and a large-sized telescope (LST). ROBAST is also used for the simulations and the development of hexagonal light concentrators that has be...

  2. R and D in photosensors and data acquisition systems for a new generation of Cosmic Ray Cherenkov and Fluorescence Imaging focal planes

    International Nuclear Information System (INIS)

    In this work we present the design, first prototypes and experimental R and D activities on the development of novel imaging cameras for Imaging Atmospheric Cherenkov and Fluorescence Telescopes. The baseline solution for the focal plane is based on a photosensor architecture instrumented with Silicon Photomultipliers (SiPMs). To decrease the trigger threshold and improve the signal-to-noise ratio for low-energy events, the Photon Counting technique is used. For very bright events the conventional Charge Integration approach is retained. The large number of channels requires a compact and modular design with minimal cabling and distance between the photosensors and the frontend. Other design requirements are an efficient light concentration system treated with an anti-reflective coating, a liquid cooling system able to keep the SiPMs at a temperature of −20°C to −10°C, a low-power frontend electronics down to 1 kW/m2 and an easy field maintenance, high reliability data acquisition and trigger system. In the baseline design, the data acquisition system is partitioned in on-board frontend and off-detector high-level trigger electronics. Extensive use of mixed-signal ASICs and low-power FPGAs for early data reduction (Level 1 trigger), compatible with a liquid cooling sub-system for temperature control is adopted. The off-detector data acquisition and higher trigger (Level 2 and Level 3) architecture is based on the VME64X standard. The boards are connected by multi-Gbps optical links to the focal plane camera. Trigger primitives are sent asynchronously to the trigger boards via data links running at their own clocks. Data and slow-control data streams are also sent over the same links with the parallel VME64X backplane kept for trigger board configuration, slow-control and final data readout. Each 8-slot 6U crate can process up to about 3.6×104 SiPM channels.

  3. Photonic chip based optical frequency comb using soliton induced Cherenkov radiation

    CERN Document Server

    Brasch, Victor; Geiselmann, Michael; Lihachev, Grigoriy; Pfeiffer, Martin H P; Gorodetsky, Michael L; Kippenberg, Tobias J

    2014-01-01

    By continuous wave pumping of a dispersion engineered, planar silicon nitride microresonator, continuously circulating, sub-30fs short temporal dissipative solitons are generated, that correspond to pulses of 6 optical cycles and constitute a coherent optical frequency comb in the spectral domain. Emission of soliton induced Cherenkov radiation caused by higher order dispersion broadens the spectral bandwidth to 2/3 of an octave, sufficient for self referencing, in excellent agreement with recent theoretical predictions and the broadest coherent microresonator frequency comb generated to date. The ability to preserve coherence over a broad spectral bandwidth using soliton induced Cherenkov radiation marks a critical milestone in the development of planar optical frequency combs, enabling on one hand application in e.g. coherent communications, broadband dual comb spectroscopy and Raman spectral imaging, while on the other hand significantly relaxing dispersion requirements for broadband microresonator frequen...

  4. Performance of the STACEE Atmospheric Cherenkov Telescope

    CERN Document Server

    Williams, D A; Boone, L M; Chantell, M C; Conner, Z; Covault, C E; Dragovan, M; Fortin, P; Gingrich, D M; Gregorich, D T; Hanna, D S; Mohanty, G B; Mukherjee, R; Ong, R A; Oser, S M; Ragan, K; Scalzo, R A; Schütte, D R; Theoret, C G; Tümer, T O; Vincent, F; Zweerink, J A

    2000-01-01

    The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) is located at the National Solar Thermal Test Facility of Sandia National Laboratories in Albuquerque, New Mexico, USA. The field of solar tracking mirrors (heliostats) around a central receiver tower is used to direct Cherenkov light from atmospheric showers onto secondary mirrors on the tower, which in turn image the light onto cameras of photomultiplier tubes. The STACEE Collaboration has previously reported a detection of the Crab Nebula with approximately 7 standard deviation significance, using 32 heliostats (STACEE-32). This result demonstrates both the viability of the technique and the suitability of the site. We are in the process of completing an upgrade to 48 heliostats (STACEE-48) en route to an eventual configuration using 64 heliostats (STACEE-64) in early 2001. In this paper, we summarize the results obtained on the sensitivity of STACEE-32 and our expectations for STACEE-48 and STACEE-64.

  5. ROBAST: Development of a ROOT-based ray-tracing library for cosmic-ray telescopes and its applications in the Cherenkov Telescope Array

    Science.gov (United States)

    Okumura, Akira; Noda, Koji; Rulten, Cameron

    2016-03-01

    We have developed a non-sequential ray-tracing simulation library, ROOT-basedsimulatorforraytracing (ROBAST), which is aimed to be widely used in optical simulations of cosmic-ray (CR) and gamma-ray telescopes. The library is written in C++, and fully utilizes the geometry library of the ROOT framework. Despite the importance of optics simulations in CR experiments, no open-source software for ray-tracing simulations that can be widely used in the community has existed. To reduce the dispensable effort needed to develop multiple ray-tracing simulators by different research groups, we have successfully used ROBAST for many years to perform optics simulations for the Cherenkov Telescope Array (CTA). Among the six proposed telescope designs for CTA, ROBAST is currently used for three telescopes: a Schwarzschild-Couder (SC) medium-sized telescope, one of SC small-sized telescopes, and a large-sized telescope (LST). ROBAST is also used for the simulation and development of hexagonal light concentrators proposed for the LST focal plane. Making full use of the ROOT geometry library with additional ROBAST classes, we are able to build the complex optics geometries typically used in CR experiments and ground-based gamma-ray telescopes. We introduce ROBAST and its features developed for CR experiments, and show several successful applications for CTA.

  6. Reverse surface-polariton cherenkov radiation

    Science.gov (United States)

    Tao, Jin; Wang, Qi Jie; Zhang, Jingjing; Luo, Yu

    2016-08-01

    The existence of reverse Cherenkov radiation for surface plasmons is demonstrated analytically. It is shown that in a metal-insulator-metal (MIM) waveguide, surface plasmon polaritons (SPPs) excited by an electron moving at a speed higher than the phase velocity of SPPs can generate Cherenkov radiation, which can be switched from forward to reverse direction by tuning the core thickness of the waveguide. Calculations are performed in both frequency and time domains, demonstrating that a radiation pattern with a backward-pointing radiation cone can be achieved at small waveguide core widths, with energy flow opposite to the wave vector of SPPs. Our study suggests the feasibility of generating and steering electron radiation in simple plasmonic systems, opening the gate for various applications such as velocity-selective particle detections.

  7. TARGET: A Digitizing And Trigger ASIC For The Cherenkov Telescope Array

    CERN Document Server

    Funk, S; Katagiri, H; Kraus, M; Okumura, A; Schoorlemmer, H; Shigenaka, A; Tajima, H; Tibaldo, L; Varner, G; Zink, A; Zorn, J

    2016-01-01

    The future ground-based gamma-ray observatory Cherenkov Telescope Array (CTA) will feature multiple types of imaging atmospheric Cherenkov telescopes, each with thousands of pixels. To be affordable, camera concepts for these telescopes have to feature low cost per channel and at the same time meet the requirements for CTA in order to achieve the desired scientific goals. We present the concept of the TeV Array Readout Electronics with GSa/s sampling and Event Trigger (TARGET) Application Specific Circuit (ASIC), envisaged to be used in the cameras of various CTA telescopes, e.g. the Gamma-ray Cherenkov Telescope (GCT), a proposed 2-Mirror Small-Sized Telescope, and the Schwarzschild-Couder Telescope (SCT), a proposed Medium-Sized Telescope. In the latest version of this readout concept the sampling and trigger parts are split into dedicated ASICs, TARGET C and T5TEA, both providing 16 parallel input channels. TARGET C features a tunable sampling rate (usually 1 GSa/s), a 16k sample deep buffer for each chann...

  8. Atmospheric Cherenkov Gamma-ray Telescopes

    CERN Document Server

    Holder, Jamie

    2015-01-01

    The stereoscopic imaging atmospheric Cherenkov technique, developed in the 1980s and 1990s, is now used by a number of existing and planned gamma-ray observatories around the world. It provides the most sensitive view of the very high energy gamma-ray sky (above 30 GeV), coupled with relatively good angular and spectral resolution over a wide field-of-view. This Chapter summarizes the details of the technique, including descriptions of the telescope optical systems and cameras, as well as the most common approaches to data analysis and gamma-ray reconstruction.

  9. A Medium Sized Schwarzschild-Couder Cherenkov Telescope Mechanical Design Proposed for the Cherenkov Telescope Array

    CERN Document Server

    Byrum, K; Benbow, W; Cameron, R; Criswell, S; Errando, M; Guarino, V; Kaaret, P; Kieda, D; Mukherjee, R; Naumann, D; Nieto, D; Northrop, R; Okumura, A; Roache, E; Rousselle, J; Schlenstedt, S; Sternberger, R; Vassiliev, V; Wakely, S; Zhao, H

    2015-01-01

    The Cherenkov Telescope Array (CTA) is an international next-generation ground-based gamma-ray observatory. CTA will be implemented as southern and northern hemisphere arrays of tens of small, medium and large-sized imaging Cherenkov telescopes with the goal of improving the sensitivity over the current-generation experiments by an order of magnitude. CTA will provide energy coverage from ~20 GeV to more than 300 TeV. The Schwarzschild-Couder (SC) medium size (9.5m) telescopes will feature a novel aplanatic two-mirror optical design capable of accommodating a wide field-of-view with significantly improved angular resolution as compared to the traditional Davies-Cotton optical design. A full-scale prototype SC medium size telescope structure has been designed and will be constructed at the Fred Lawrence Whipple Observatory in southern Arizona during the fall of 2015. concentrate on the novel features of the design.

  10. The Atmospheric Monitoring Strategy for the Cherenkov Telescope Array

    CERN Document Server

    Daniel, M K

    2015-01-01

    The Imaging Atmospheric Cherenkov Technique (IACT) is unusual in astronomy as the atmosphere actually forms an intrinsic part of the detector system, with telescopes indirectly detecting very high energy particles by the generation and transport of Cherenkov photons deep within the atmosphere. This means that accurate measurement, characterisation and monitoring of the atmosphere is at the very heart of successfully operating an IACT system. The Cherenkov Telescope Array (CTA) will be the next generation IACT observatory with an ambitious aim to improve the sensitivity of an order of magnitude over current facilities, along with corresponding improvements in angular and energy resolution and extended energy coverage, through an array of Large (23m), Medium (12m) and Small (4m) sized telescopes spread over an area of order ~km$^2$. Whole sky coverage will be achieved by operating at two sites: one in the northern hemisphere and one in the southern hemisphere. This proceedings will cover the characterisation of...

  11. The GCT camera for the Cherenkov Telescope Array

    CERN Document Server

    Brown, Anthony M; Allan, D; Amans, J P; Armstrong, T P; Balzer, A; Berge, D; Boisson, C; Bousquet, J -J; Bryan, M; Buchholtz, G; Chadwick, P M; Costantini, H; Cotter, G; Daniel, M K; De Franco, A; De Frondat, F; Dournaux, J -L; Dumas, D; Fasola, G; Funk, S; Gironnet, J; Graham, J A; Greenshaw, T; Hervet, O; Hidaka, N; Hinton, J A; Huet, J -M; Jegouzo, I; Jogler, T; Kraus, M; Lapington, J S; Laporte, P; Lefaucheur, J; Markoff, S; Melse, T; Mohrmann, L; Molyneux, P; Nolan, S J; Okumura, A; Osborne, J P; Parsons, R D; Rosen, S; Ross, D; Rowell, G; Sato, Y; Sayede, F; Schmoll, J; Schoorlemmer, H; Servillat, M; Sol, H; Stamatescu, V; Stephan, M; Stuik, R; Sykes, J; Tajima, H; Thornhill, J; Tibaldo, L; Trichard, C; Vink, J; Watson, J J; White, R; Yamane, N; Zech, A; Zink, A; Zorn, J

    2016-01-01

    The Gamma-ray Cherenkov Telescope (GCT) is proposed for the Small-Sized Telescope component of the Cherenkov Telescope Array (CTA). GCT's dual-mirror Schwarzschild-Couder (SC) optical system allows the use of a compact camera with small form-factor photosensors. The GCT camera is ~0.4 m in diameter and has 2048 pixels; each pixel has a ~0.2 degree angular size, resulting in a wide field-of-view. The design of the GCT camera is high performance at low cost, with the camera housing 32 front-end electronics modules providing full waveform information for all of the camera's 2048 pixels. The first GCT camera prototype, CHEC-M, was commissioned during 2015, culminating in the first Cherenkov images recorded by a SC telescope and the first light of a CTA prototype. In this contribution we give a detailed description of the GCT camera and present preliminary results from CHEC-M's commissioning.

  12. Normalized and Asynchronous Mirror Alignment for Cherenkov Telescopes

    CERN Document Server

    Ahnen, M L; Balbo, M; Bergmann, M; Biland, A; Blank, M; Bretz, T; Bruegge, K A; Buss, J; Domke, M; Dorner, D; Einecke, S; Hempfling, C; Hildebrand, D; Hughes, G; Lustermann, W; Mannheim, K; Mueller, S A; Neise, D; Neronov, A; Noethe, M; Overkemping, A -K; Paravac, A; Pauss, F; Rhode, W; Shukla, A; Temme, F; Thaele, J; Toscano, S; Vogler, P; Walter, R; Wilbert, A

    2016-01-01

    Imaging Atmospheric Cherenkov Telescopes (IACTs) need imaging optics with large apertures and high image intensities to map the faint Cherenkov light emitted from cosmic ray air showers onto their image sensors. Segmented reflectors fulfill these needs, and as they are composed from mass production mirror facets they are inexpensive and lightweight. However, as the overall image is a superposition of the individual facet images, alignment is a challenge. Here we present a computer vision based star tracking alignment method, which also works for limited or changing star light visibility. Our method normalizes the mirror facet reflection intensities to become independent of the reference star's intensity or the cloud coverage. Using two CCD cameras, our method records the mirror facet orientations asynchronously of the telescope drive system, and thus makes the method easy to integrate into existing telescopes. It can be combined with remote facet actuation, but does not require one to work. Furthermore, it ca...

  13. Cherenkov counter for particle identification test beam

    International Nuclear Information System (INIS)

    The Cherenkov counter used for selecting electrons of the test beam has been studied in this article. The design, manufacture, assembly and testing of the Cherenkov counter are described. And the performance of this counter is measured. The CO2 gas is used as Cherenkov radiator, the XP2020Q photomultiplier is applied for recording signals of the Cherenkov light. The (99.0±0.5)% efficiency of the electron selection has been reached

  14. The Gamma-ray Cherenkov Telescope for the Cherenkov Telescope Array

    CERN Document Server

    Tibaldo, L; Allan, D; Amans, J -P; Armstrong, T P; Balzer, A; Berge, D; Boisson, C; Bousquet, J -J; Brown, A M; Bryan, M; Buchholtz, G; Chadwick, P M; Costantini, H; Cotter, G; Daniel, M K; De Franco, A; De Frondat, F; Dournaux, J -L; Dumas, D; Ernenwein, J -P; Fasola, G; Funk, S; Gironnet, J; Graham, J A; Greenshaw, T; Hervet, O; Hidaka, N; Hinton, J A; Huet, J -M; Jankowsky, D; Jegouzo, I; Jogler, T; Kraus, M; Lapington, J S; Laporte, P; Lefaucheur, J; Markoff, S; Melse, T; Mohrmann, L; Molyneux, P; Nolan, S J; Okumura, A; Osborne, J P; Parsons, R D; Rosen, S; Ross, D; Rowell, G; Rulten, C B; Sato, Y; Sayede, F; Schmoll, J; Schoorlemmer, H; Servillat, M; Sol, H; Stamatescu, V; Stephan, M; Stuik, R; Sykes, J; Tajima, H; Thornhill, J; Trichard, C; Vink, J; Watson, J J; White, R; Yamane, N; Zech, A; Zink, A; Zorn, J

    2016-01-01

    The Cherenkov Telescope Array (CTA) is a forthcoming ground-based observatory for very-high-energy gamma rays. CTA will consist of two arrays of imaging atmospheric Cherenkov telescopes in the Northern and Southern hemispheres, and will combine telescopes of different types to achieve unprecedented performance and energy coverage. The Gamma-ray Cherenkov Telescope (GCT) is one of the small-sized telescopes proposed for CTA to explore the energy range from a few TeV to hundreds of TeV with a field of view $\\gtrsim 8^\\circ$ and angular resolution of a few arcminutes. The GCT design features dual-mirror Schwarzschild-Couder optics and a compact camera based on densely-pixelated photodetectors as well as custom electronics. In this contribution we provide an overview of the GCT project with focus on prototype development and testing that is currently ongoing. We present results obtained during the first on-telescope campaign in late 2015 at the Observatoire de Paris-Meudon, during which we recorded the first Cher...

  15. Molecular imaging. Fundamentals and applications

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Jie (ed.) [Chinese Academy of Sciences, Beijing (China). Intelligent Medical Research Center

    2013-07-01

    Covers a wide range of new theory, new techniques and new applications. Contributed by many experts in China. The editor has obtained the National Science and Technology Progress Award twice. ''Molecular Imaging: Fundamentals and Applications'' is a comprehensive monograph which describes not only the theory of the underlying algorithms and key technologies but also introduces a prototype system and its applications, bringing together theory, technology and applications. By explaining the basic concepts and principles of molecular imaging, imaging techniques, as well as research and applications in detail, the book provides both detailed theoretical background information and technical methods for researchers working in medical imaging and the life sciences. Clinical doctors and graduate students will also benefit from this book.

  16. The Photodetector Plane of the 4m Davies Cotton Small Size Telescope for the Cherenkov Telescope Array

    CERN Document Server

    Boccone, V; Basili, A; Christov, A; della Volpe, M; Montaruli, T

    2013-01-01

    Photomultipliers (PMTs) are currently adopted for the photodetector plane of Imaging Atmospheric Cherenkov Telescopes (IACTs). Even though PMT quantum efficiency has improved impressively in the recent years, one of the main limitation for their application in the gamma-astronomy field - the impossibility to operate with moon light - still remains. As a matter of fact, the light excess would lead to significant and faster camera ageing. Solid state detectors, in particular Geiger-mode avalanche photo-diodes (G-APDs) represent a valuable alternative solution to overcome this limitation as demonstrated in the field by the FACT experiment (The First G- APD Cherenkov Telescope). They can be regarded as a more promising long term approach, which can be easily adopted for the new generation of cameras and for the Cherenkov Telescope Array (CTA). We describe here the Photo-Detector Plane (PDP) of the camera for the 4 m Davies Cotton CTA Small Size Telescopes, for which large area G-APD coupled to non-imaging light c...

  17. Quenching the scintillation in CF{sub 4} Cherenkov gas radiator

    Energy Technology Data Exchange (ETDEWEB)

    Blake, T. [Department of Physics, University of Warwick, Coventry (United Kingdom); D' Ambrosio, C. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Easo, S. [STFC Rutherford Appleton Laboratory, Didcot (United Kingdom); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Eisenhardt, S. [School of Physics and Astronomy, University of Edinburgh, Edinburgh (United Kingdom); Fitzpatrick, C. [Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne (Switzerland); Forty, R.; Frei, C. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Gibson, V. [Cavendish Laboratory, University of Cambridge, Cambridge (United Kingdom); Gys, T. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Harnew, N.; Hunt, P. [Department of Physics, University of Oxford, Oxford (United Kingdom); Jones, C.R. [Cavendish Laboratory, University of Cambridge, Cambridge (United Kingdom); Lambert, R.W. [Nikhef National Institute for Subatomic Physics and VU University Amsterdam, Amsterdam (Netherlands); Matteuzzi, C. [Sezione INFN di Milano Bicocca, Milano (Italy); Muheim, F. [School of Physics and Astronomy, University of Edinburgh, Edinburgh (United Kingdom); Papanestis, A., E-mail: antonis.papanestis@stfc.ac.uk [STFC Rutherford Appleton Laboratory, Didcot (United Kingdom); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Perego, D.L. [Sezione INFN di Milano Bicocca, Milano (Italy); Università di Milano Bicocca, Milano (Italy); Piedigrossi, D. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Plackett, R. [Imperial College London, London (United Kingdom); Powell, A. [Department of Physics, University of Oxford, Oxford (United Kingdom); and others

    2015-08-11

    CF{sub 4} is used as a Cherenkov gas radiator in one of the Ring Imaging Cherenkov detectors at the LHCb experiment at the CERN Large Hadron Collider. CF{sub 4} is well known to have a high scintillation photon yield in the near and far VUV, UV and in the visible wavelength range. A large flux of scintillation photons in our photon detection acceptance between 200 and 800 nm could compromise the particle identification efficiency. We will show that this scintillation photon emission system can be effectively quenched, consistent with radiationless transitions, with no significant impact on the photons resulting from Cherenkov radiation.

  18. Cherenkov angle and charge reconstruction with the RICH detector of the AMS experiment

    CERN Document Server

    Barão, F; Borges, J; Gonçalves, P; Pimenta, M; Pérez, I

    2003-01-01

    The Alpha Magnetic Spectrometer experiment to be installed on the International Space Station will be equipped with a proximity focusing Ring Imaging Cherenkov (RICH) detector, for measurements of particle electric charge and velocity. In this note, two possible methods for reconstructing the Cherenkov angle and the electric charge with the RICH are discussed. A Likelihood method for the Cherenkov angle reconstruction was applied leading to a velocity determination for protons with a resolution of around 0.1%. The existence of a large fraction of background photons which can vary from event to event implied a charge reconstruction method based on an overall efficiency estimation on an event-by-event basis.

  19. Normalized and asynchronous mirror alignment for Cherenkov telescopes

    Science.gov (United States)

    Ahnen, M. L.; Baack, D.; Balbo, M.; Bergmann, M.; Biland, A.; Blank, M.; Bretz, T.; Bruegge, K. A.; Buss, J.; Domke, M.; Dorner, D.; Einecke, S.; Hempfling, C.; Hildebrand, D.; Hughes, G.; Lustermann, W.; Mannheim, K.; Mueller, S. A.; Neise, D.; Neronov, A.; Noethe, M.; Overkemping, A.-K.; Paravac, A.; Pauss, F.; Rhode, W.; Shukla, A.; Temme, F.; Thaele, J.; Toscano, S.; Vogler, P.; Walter, R.; Wilbert, A.

    2016-09-01

    Imaging Atmospheric Cherenkov Telescopes (IACTs) need imaging optics with large apertures and high image intensities to map the faint Cherenkov light emitted from cosmic ray air showers onto their image sensors. Segmented reflectors fulfill these needs, and as they are composed from mass production mirror facets they are inexpensive and lightweight. However, as the overall image is a superposition of the individual facet images, alignment is a challenge. Here we present a computer vision based star tracking alignment method, which also works for limited or changing star light visibility. Our method normalizes the mirror facet reflection intensities to become independent of the reference star's intensity or the cloud coverage. Using two CCD cameras, our method records the mirror facet orientations asynchronously of the telescope drive system, and thus makes the method easy to integrate into existing telescopes. It can be combined with remote facet actuation, but does not require one to work. Furthermore, it can reconstruct all individual mirror facet point spread functions without moving any mirror. We present alignment results on the 4 m First Geiger-mode Avalanche Cherenkov Telescope (FACT).

  20. BIOLUMINESCENCE IMAGING: PROGRESS AND APPLICATIONS

    OpenAIRE

    Badr, Christian E.; Tannous, Bakhos A

    2011-01-01

    Application of bioluminescence imaging has grown tremendously in the past decade and has significantly contributed to the core conceptual advances in biomedical research. This technology provides valuable means for monitoring of different biological processes for immunology, oncology, virology and neuroscience. In this review, we will discuss current trends in bioluminescence and its application in different fields with emphasis on cancer research.

  1. Photosensor Characterization for the Cherenkov Telescope Array: Silicon Photomultiplier versus Multi-Anode Photomultiplier Tube

    OpenAIRE

    Bouvier, Aurelien; Gebremedhin, Lloyd; Johnson, Caitlin; Kuznetsov, Andrey; Williams, David; Otte, Nepomuk; Strausbaugh, Robert; Hidaka, Naoya; Tajima, Hiroyasu; Hinton, Jim; White, Richard; Errando, Manel; Mukherjee, Reshmi

    2013-01-01

    Photomultiplier tube technology has been the photodetector of choice for the technique of imaging atmospheric Cherenkov telescopes since its birth more than 50 years ago. Recently, new types of photosensors are being contemplated for the next generation Cherenkov Telescope Array. It is envisioned that the array will be partly composed of telescopes using a Schwarzschild-Couder two mirror design never built before which has significantly improved optics. The camera of this novel optical design...

  2. Prototyping the graphical user interface for the operator of the Cherenkov Telescope Array

    OpenAIRE

    Sadeh, Iftach; Oya, Igor; Schwarz, Joseph; Pietriga, Emmanuel

    2016-01-01

    The Cherenkov Telescope Array (CTA) is a planned gamma-ray observatory. CTA will incorporate about 100 imaging atmospheric Cherenkov telescopes (IACTs) at a Southern site, and about 20 in the North. Previous IACT experiments have used up to five telescopes. Subsequently, the design of a graphical user interface (GUI) for the operator of CTA involves new challenges. We present a GUI prototype, the concept for which is being developed in collaboration with experts from the field of Human-Comput...

  3. Cherenkov particle identification in FOCUS

    CERN Document Server

    Link, J M; Alimonti, G; Anjos, J C; Arena, V; Bediaga, I; Bianco, S; Boca, G; Bonomi, G; Boschini, M; Butler, J N; Carrillo, S; Casimiro, E; Cawlfield, C; Cheung, H W K; Cho, K; Chung, Y S; Cinquini, L; Cuautle, E; Cumalat, J P; D'Angelo, P; Di Corato, M; Dini, P; Engh, D; Fabbri, Franco Luigi; Gaines, I; Garbincius, P H; Gardner, R; Garren, L A; Giammarchi, M; Gianini, G; Gottschalk, E; Göbel, C; Handler, T; Hernández, H; Hosack, M; Inzani, P; Johns, W E; Kang, J S; Kasper, P H; Kim, D Y; Ko, B R; Kreymer, A E; Kryemadhi, A; Kutschke, R; Kwak, J W; Lee, K B; Leveraro, F; Liguori, G; Magnin, J; Malvezzi, S; Massafferri, A; Menasce, D; Merlo, M M; Mezzadri, M; Milazzo, L; Miranda, J M D; Mitchell, R; Montiel, E; Moroni, L; Méndez, H; Méndez, L; Nehring, M S; O'Reilly, B; Olaya, D; Pantea, D; Paris, A; Park, H; Park, K S; Pedrini, D; Pepe, I M; Pontoglio, C; Prelz, F; Quinones, J; Rahimi, A; Ramírez, J E; Ratti, S P; Reis, A C D; Reyes, M; Riccardi, C; Rivera, C; Rovere, M; Sala, S; Sarwar, S; Segoni, I; Sheaff, M; Sheldon, P D; Stenson, K; Sánchez-Hernández, A; Uribe, C; Vaandering, E W; Vitulo, P; Vázquez, F; Webster, M; Wilson, J R; Wiss, J; Xiong, W; Yager, P M; Zallo, A; Zhang, Y

    2002-01-01

    We describe the algorithm used to identify charged tracks in the fixed-target charm-photoproduction experiment FOCUS. We begin by describing the new algorithm and contrast this approach with that used in our preceding experiment - E687. We next illustrate the algorithm's performance using physics signals. Finally, we briefly describe some of the methods used to monitor the quantum efficiency and noise of the Cherenkov cells.

  4. Cherenkov particle identification in FOCUS

    Energy Technology Data Exchange (ETDEWEB)

    Link, J.M.; Reyes, M.; Yager, P.M.; Anjos, J.C.; Bediaga, I.; Goebel, C.; Magnin, J.; Massafferri, A.; Miranda, J.M. de; Pepe, I.M.; Reis, A.C. dos; Carrillo, S.; Casimiro, E.; Cuautle, E.; Sanchez-Hernandez, A.; Uribe, C.; Vazquez, F.; Cinquini, L.; Cumalat, J.P.; O' Reilly, B.; Ramirez, J.E.; Vaandering, E.W.; Butler, J.N.; Cheung, H.W.K.; Gaines, I.; Garbincius, P.H.; Garren, L.A.; Gottschalk, E.; Kasper, P.H.; Kreymer, A.E.; Kutschke, R.; Bianco, S.; Fabbri, F.L.; Sarwar, S.; Zallo, A.; Cawlfield, C.; Kim, D.Y.; Park, K.S.; Rahimi, A.; Wiss, J. E-mail: jew@uiuc.edu; Gardner, R.; Kryemadhi, A.; Chung, Y.S.; Kang, J.S.; Ko, B.R.; Kwak, J.W.; Lee, K.B.; Park, H.; Alimonti, G.; Boschini, M.; D' Angelo, P.; DiCorato, M.; Dini, P.; Giammarchi, M.; Inzani, P.; Leveraro, F.; Malvezzi, S.; Menasce, D.; Mezzadri, M.; Milazzo, L.; Moroni, L.; Pedrini, D.; Pontoglio, C.; Prelz, F.; Rovere, M.; Sala, S.; Davenport III, T.F.; Agostino, L.; Arena, V.; Boca, G.; Bonomi, G.; Gianini, G.; Liguori, G.; Merlo, M.M.; Pantea, D.; Ratti, S.P.; Riccardi, C.; Segoni, I.; Vitulo, P.; Hernandez, H.; Lopez, A.M.; Mendez, H.; Mendez, L.; Montiel, E.; Olaya, D.; Paris, A.; Quinones, J.; Rivera, C.; Xiong, W.; Zhang, Y.; Wilson, J.R.; Cho, K.; Handler, T.; Mitchell, R.; Engh, D.; Johns, W.E.; Hosack, M.; Nehring, M.S.; Sheldon, P.D.; Stenson, K.; Webster, M.S.; Sheaff, M

    2002-05-21

    We describe the algorithm used to identify charged tracks in the fixed-target charm-photoproduction experiment FOCUS. We begin by describing the new algorithm and contrast this approach with that used in our preceding experiment - E687. We next illustrate the algorithm's performance using physics signals. Finally, we briefly describe some of the methods used to monitor the quantum efficiency and noise of the Cherenkov cells.

  5. Biomedical Imaging Principles and Applications

    CERN Document Server

    Salzer, Reiner

    2012-01-01

    This book presents and describes imaging technologies that can be used to study chemical processes and structural interactions in dynamic systems, principally in biomedical systems. The imaging technologies, largely biomedical imaging technologies such as MRT, Fluorescence mapping, raman mapping, nanoESCA, and CARS microscopy, have been selected according to their application range and to the chemical information content of their data. These technologies allow for the analysis and evaluation of delicate biological samples, which must not be disturbed during the profess. Ultimately, this may me

  6. Physics for Medical Imaging Applications

    CERN Document Server

    Caner, Alesssandra; Rahal, Ghita

    2007-01-01

    The book introduces the fundamental aspects of digital imaging and covers four main themes: Ultrasound techniques and imaging applications; Magnetic resonance and MPJ in hospital; Digital imaging with X-rays; and Emission tomography (PET and SPECT). Each of these topics is developed by analysing the underlying physics principles and their implementation, quality and safety aspects, clinical performance and recent advancements in the field. Some issues specific to the individual techniques are also treated, e.g. choice of radioisotopes or contrast agents, optimisation of data acquisition and st

  7. Medical imaging technology and applications

    CERN Document Server

    Iniewski, Krzysztof

    2014-01-01

    The book has two intentions. First, it assembles the latest research in the field of medical imaging technology in one place. Detailed descriptions of current state-of-the-art medical imaging systems (comprised of x-ray CT, MRI, ultrasound, and nuclear medicine) and data processing techniques are discussed. Information is provided that will give interested engineers and scientists a solid foundation from which to build with additional resources. Secondly, it exposes the reader to myriad applications that medical imaging technology has enabled.

  8. Cherenkov radiation threshold in random inhomogeneous media

    CERN Document Server

    Grichine, V M

    2009-01-01

    Cherenkov radiation in media with random inhomogeneities like aerogel or Earth atmosphere is discussed. The spectral-angular distribution of Cherenkov photons emitted by relativistic charged particle and averaged over the dielectric permittivity fluctuations shows angular broadening similarly to the case of media with the photon absorption. The broadening results in the smoothing of Cherenkov threshold, and therefore media with strong photon scattering have more extended dependence of Cherenkov light output on the particle speed. It can be potentially used for the particle identification

  9. Progress in Cherenkov femtosecond fiber lasers

    DEFF Research Database (Denmark)

    Liu, Xiaomin; Svane, Ask Sebastian; Lægsgaard, Jesper;

    2016-01-01

    We review the recent developments in the field of ultrafast Cherenkov fiber lasers. Two essential properties of such laser systems—broad wavelength tunability and high efficiency of Cherenkov radiation wavelength conversion are discussed. The exceptional performance of the Cherenkov fiber laser...... Cherenkov laser with all-fiber architecture is presented and discussed. Operating in the visible range, it delivers 100–200 fs wavelength-tunable pulses with multimilliwatt output power and exceptionally low noise figure an order of magnitude lower than the traditional wavelength tunable supercontinuumbased...

  10. Stellar intensity interferometry: Optimizing air Cherenkov telescope array layouts

    CERN Document Server

    Jensen, Hannes; LeBohec, Stephan; Nuñez, Paul D; 10.1117/12.856412

    2010-01-01

    Kilometric-scale optical imagers seem feasible to realize by intensity interferometry, using telescopes primarily erected for measuring Cherenkov light induced by gamma rays. Planned arrays envision 50--100 telescopes, distributed over some 1--4 km$^2$. Although array layouts and telescope sizes will primarily be chosen for gamma-ray observations, also their interferometric performance may be optimized. Observations of stellar objects were numerically simulated for different array geometries, yielding signal-to-noise ratios for different Fourier components of the source images in the interferometric $(u,v)$-plane. Simulations were made for layouts actually proposed for future Cherenkov telescope arrays, and for subsets with only a fraction of the telescopes. All large arrays provide dense sampling of the $(u,v)$-plane due to the sheer number of telescopes, irrespective of their geographic orientation or stellar coordinates. However, for improved coverage of the $(u,v)$-plane and a wider variety of baselines (...

  11. A ring imaging Cherenkov counter for the AMS experiment: simulation, prototype and perspective; Un imageur d'anneaux tcherenkov pour l'experience AMS: simulation, prototypie et perspectives physiques

    Energy Technology Data Exchange (ETDEWEB)

    Thuillier, T

    2000-05-01

    The AMS spectrometer is scheduled to be installed on the International Space Station ISS in 2003. The detector will be equipped with a Ring Imaging Cherenkov Counter (RICH). The report starts with a presentation of the physics goals of AMS and continues with a description of the spectrometer. The RICH detector response and event reconstruction is then described and detailed. The presentation proceeds with a simulation study of cosmic ray nuclei expected with the AMS RICH counter in space. Next, the thesis reports on the research and development of a RICH prototype built and tested in the period 1997-1999 in the Grenoble Institute of Nuclear Science (ISN). The response of the prototype and its calibration are described. Tests have been performed with cosmic rays at ground and ion beam at GSI-Darmstadt. The data analysis of the test campaigns is then presented and compared with simulation results. Finally, a dedicated test of Albedo particle Rejection Power of the RICH detector is reported. (author)

  12. SU-E-I-87: Calibrating Cherenkov Emission to Match Superficial Dose in Tissue

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, R; Pogue, B [Dartmouth College, Hanover, NH (United States); Glaser, A; Gladstone, D [Dartmouth Hitchcock-Medical Center, Hanover, NH (United States)

    2015-06-15

    Purpose: Through Monte Carlo simulations and phantom studies, the dominant factors affecting the calibration of superficial Cherenkov intensity to absolute surface dose was investigated, including tissue optical properties, curvatures, beam properties and imaging angle. Methods: The phasespace files for the TrueBeam system from Varian were used in GAMOS (a GEANT4 based Monte Carlo simulation toolkit) to simulate surface emission Cherenkov signals and the correlated deposited dose. The parameters examined were: i) different tissue optical properties (skin color from light to dark), ii) beam types (X-ray and electron beam), iii) beam energies, iv) thickness of tissues (2.5 cm to 20 cm), v) SSD (80 cm to 120 cm), vi) field sizes (0.5×0.5 cm2 to 20×20 cm2), vii) entrance/exit sides, viii) curvatures (cylinders with diameters from 2.5 cm to 20cm) and ix) imaging angles (0 to 90 degrees). In a specific case, for any Cherenkov photon emitted from the surface, the original position and direction, final position and direction and energy were recorded. Similar experimental measurements were taken in a range of the most pertinent parameters using tissue phantoms. Results: Combining the dose distribution and sampling sensitivity of Cherenkov emission, quantitatively accurate calibration factors (the amount of radiation dose represented by a single Cherenkov photon) were calculated. The data showed relatively large dependence upon different optical properties, curvature, entrance/exit and beam types. For a diffusive surface, the calibration factor was insensitive to imaging angles smaller than 60 degrees. Normalization with the reflectance image was experimentally validated as a simple and accurate method for calibrations of different optical properties. Conclusion: This study sheds light on how and to what extent different conditions affect the calibration from Cherenkov intensity to absolute superficial dose and provides practical solutions to allow quantitative Cherenkov

  13. Simulated response of Cherenkov glass detectors to MeV photons

    Energy Technology Data Exchange (ETDEWEB)

    Hayward, J P [University of Tennessee, Knoxville (UTK); Bell, Zane W [ORNL; Boatner, Lynn A [ORNL; Hobbs, C. L. [University of Tennessee, Knoxville (UTK); Johnson, Rose E [ORNL; Ramey, Joanne Oxendine [ORNL; Jellison Jr, Gerald Earle [ORNL

    2012-01-01

    Cherenkov detectors are widely used for par ticle identification in high-energy physics and for track imaging in astrophysics. Glass Cherenkov detectors that are sensitive to beta emissions originating from neutron activation have been demonstrated recently as a potential replacement for activation foils. In this work, we evaluate Cherenkov glass detectors for sensitivity and specificity to MeV photons through simulations using Geant4. The model has been previously compared with measurements of isotopic gamma sources. It includes Cherenkov gener ation, light transport, light collection, photoelectron pro duction and time response in photomultiplier tubes. The model incorporates measured, wavelength-dependent absorption and refractive index data. Simulations are con ducted for glasses the size of fabricated samples and also for the same glasses in monolithic, square-meter-size. Implications for selective detection of MeV photons are discussed.

  14. Raman Imaging Techniques and Applications

    CERN Document Server

    2012-01-01

    Raman imaging has long been used to probe the chemical nature of a sample, providing information on molecular orientation, symmetry and structure with sub-micron spatial resolution. Recent technical developments have pushed the limits of micro-Raman microscopy, enabling the acquisition of Raman spectra with unprecedented speed, and opening a pathway to fast chemical imaging for many applications from material science and semiconductors to pharmaceutical drug development and cell biology, and even art and forensic science. The promise of tip-enhanced raman spectroscopy (TERS) and near-field techniques is pushing the envelope even further by breaking the limit of diffraction and enabling nano-Raman microscopy.

  15. Low-Noise Operation of All-Fiber Femtosecond Cherenkov Laser

    DEFF Research Database (Denmark)

    Liu, Xiaomin; Villanueva Ibáñez, Guillermo Eduardo; Lægsgaard, Jesper;

    2013-01-01

    We investigate the noise properties of a femtosecond all-fiber Cherenkov radiation source with emission wavelength around 600 nm, based on an Yb-fiber laser and a highly-nonlinear photonic crystal fiber. A relative intensity noise as low as - 103 dBc/Hz, corresponding to 2.48 % pulse......-to-pulse fluctuation in energy, was observed at the Cherenkov radiation output power of 4.3 mW, or 150 pJ pulse energy. This pulse-to-pulse fluctuation is at least 10.6 dB lower compared to spectrally-sliced supercontinuum sources traditionally used for ultrafast fiberbased generation at visible wavelengths. Low noise...... makes allfiber Cherenkov sources promising for biophotonics applications such as multi-photon microscopy, where minimum pulse-to-pulse energy fluctuation is required. We present the dependency of the noise figure on both the Cherenkov radiation output power and its spectrum....

  16. TORCH - a Cherenkov-based time-of-flight detector

    CERN Document Server

    van Dijk, M W U; Cowie, E N; Cussans, D; D' Ambrosio, C; Forty, R; Frei, C; Gys, T; Piedigrossi, D; Castillo Garcia, L; Fopma, J; Gao, R; Harnew, N; Keri, T

    2014-01-01

    TORCH is an innovative high-precision time-of-flight system to provide particle identification in the difficult intermediate momentum region up to 10 GeV/c. It is also suitable for large-area applications. The detector provides a time-of-flight measurement from the imaging of Cherenkov photons emitted in a 1 cm thick quartz radiator. The photons propagate by total internal reflection to the edge of the quartz plate, where they are focused onto an array of photon detectors at the periphery. A time-of-flight resolution of about 10–15 ps per incident charged particle needs to be achieved for a three sigma kaon–pion separation up to 10 GeV/c momentum for the TORCH located 9.5 m from the interaction point. Given ∼ 30 detected photons per incident charged particle, this requires measuring the time-of-arrival of individual photons to about 70 ps. This paper will describe the design of a TORCH prototype involving a number of ground-breaking and challenging techniques.

  17. Study of a Cherenkov TOF-PET module

    Science.gov (United States)

    Korpar, S.; Dolenec, R.; Križan, P.; Pestotnik, R.; Stanovnik, A.

    2013-12-01

    An apparatus, consisting of two PbF2 crystals, each coupled to a multichannel plate photomultiplier (MCP-PMT), has been constructed in order to measure the time-of-flight (TOF) of the two 511 keV annihilation photons produced in positron emission tomography (PET). Excellent timing is achieved by detecting the prompt Cherenkov photons produced by the absorption of the 511 keV gamma photons. The present work describes the measurement and image reconstruction of two 22Na point sources. In addition, the influence of the radiator thickness and the Cherenkov light absorption cut-off of the crystal on the efficiency and the timing resolution have been studied by Monte Carlo simulation.

  18. Photo multiplier tubes candidates for the Cherenkov telescope array project

    International Nuclear Information System (INIS)

    Photo Multiplier Tubes (PMTs) are the most wide spread detectors for fast low-level light signals. They are commonly used as standard light sensors for camera systems in imaging atmospheric Cherenkov telescopes. Years ago, an improvement program for the PMT candidates for the Cherenkov Telescope Array (CTA) project was initialized with the companies Hamamatsu Photonics K.K. (Japan) and Electron Tubes Enterprises Ltd. (England). CTA is the next generation of imaging atmospheric Cherenkov telescopes for high energy gamma ray astrophysics. Therefore, we need PMTs with outstanding good parameters concerning quantum efficiency, pulse width, after-pulsing and transit time spread. The currently available ''super-bialkali'' PMTs show a peak Quantum Efficiency of 40% and have an enhanced collection efficiency of up to 95-98% for wavelengths≥400 nm. The pulse width averages around 3ns at a gain of 40000. Also, the after-pulsing for a set threshold level of ≥4 photo electrons is reduced down to 0,02%. We report on the measurement results of PMT R-12292-100 from Hamamatsu as the final version and the intermediate version PMT D569/3SA from Electron Tubes Enterprises as candidate PMTs for the CTA project.

  19. Novel Photo Multiplier Tubes for the Cherenkov Telescope Array Project

    CERN Document Server

    Toyama, Takeshi; Dickinson, Hugh; Fruck, Christian; Hose, Jürgen; Kellermann, Hanna; Knötig, Max; Lorenz, Eckart; Menzel, Uta; Nakajima, Daisuke; Orito, Reiko; Paneque, David; Schweizer, Thomas; Teshima, Masahiro; Yamamoto, Tokonatsu

    2013-01-01

    Currently the standard light sensors for imaging atmospheric Cherenkov telescopes are the classical photo multiplier tubes that are using bialkali photo cathodes. About eight years ago we initiated an improvement program with the Photo Multiplier Tube (PMT) manufacturers Hamamatsu (Japan), Electron Tubes Enterprises (England) and Photonis (France) for the needs of imaging atmospheric Cherenkov telescopes. As a result, after about 40 years of stagnation of the peak Quantum Efficiency (QE) on the level of 25-27%, new PMTs appeared with a peak QE of 35%. These have got the name super-bialkali. The second significant upgrade has happened very recently, as a result of a dedicated improvement program for the candidate PMT for Cherenkov Telescope Array. The latter is going to be the next generation major instrument in the field of very high energy gamma astrophysics and will consist of over 100 telescopes of three different sizes of 23m, 12m and 4-7m, located both in southern and northern hemispheres. Now PMTs with ...

  20. Bioluminescence imaging characteristics and application

    International Nuclear Information System (INIS)

    Bioluminescence imaging (BLI) by luciferase gene marked cells or DNA, in the presence of ATP and oxygen, catalytic oxidation reaction of fluorescein luminescence. So that it can directly monitor in vivo cell activity and gene behavior. In this paper, by comparing the BLI and MRI, PET, radiography of the similarities and differences, as well as about their cancer, stem cells and immune cells transportation, apoptosis and other aspects of the application, in order to better provide the basis for promoting the application of BLI. (authors)

  1. NICHE: Using Cherenkov radiation to extend Telescope Array to sub-PeV energies

    Science.gov (United States)

    Bergman, Douglas; Krizmanic, John; Tsunesada, Yoshiki; Abu-Zayyad, Tareq; Belz, John; Thomson, Gordon

    2016-03-01

    The Non-Imaging CHErenkov (NICHE) Array will measure the flux and nuclear composition evolution of cosmic rays (CRs) from below 1 PeV to 1 EeV. NICHE will be co-sited with the Telescope Array (TA) Low Energy (TALE) extension, and will observe events simultaneously with the TALE telescopes acting in imaging-Cherenkov mode. This will be the first hybrid-Cherenkov (simultaneous imaging and non-imaging Cherenkov) measurements of CRs in the Knee region of the CR energy spectrum. NICHE uses easily deployable detectors to measure the amplitude and time-spread of the air-shower Cherenkov signal to achieve an event-by-event measurement of Xmax and energy, each with excellent resolution. First generation detectors are under construction and will form an initial prototype array (j-NICHE) that will be deployed in Summer 2016. In this talk, the NICHE design, array performance, prototype development, and status will be discussed as well as NICHE's ability to measure the cosmic ray nuclear composition as a function of energy.

  2. ROBAST: Development of a ROOT-Based Ray-Tracing Library for Cosmic-Ray Telescopes and its Applications in the Cherenkov Telescope Array

    CERN Document Server

    Okumura, Akira; Rulten, Cameron

    2016-01-01

    We have developed a non-sequential ray-tracing simulation library, ROOT-based simulator for ray tracing (ROBAST), which is aimed to be widely used in optical simulations of cosmic-ray (CR) and gamma-ray telescopes. The library is written in C++, and fully utilizes the geometry library of the ROOT framework. Despite the importance of optics simulations in CR experiments, no open-source software for ray-tracing simulations that can be widely used in the community has existed. To reduce the dispensable effort needed to develop multiple ray-tracing simulators by different research groups, we have successfully used ROBAST for many years to perform optics simulations for the Cherenkov Telescope Array (CTA). Among the six proposed telescope designs for CTA, ROBAST is currently used for three telescopes: a Schwarzschild-Couder (SC) medium-sized telescope, one of SC small-sized telescopes, and a large-sized telescope (LST). ROBAST is also used for the simulation and development of hexagonal light concentrators propose...

  3. The Efficient Discrimination Of Electron And Pi-zero Events In A Water Cherenkov Detector And The Application To Neutrino Oscillation Experiments

    CERN Document Server

    Barszczak, T

    2005-01-01

    Super-Kamiokande, a large water Cherenkov detector, observed atmospheric neutrinos produced by interactions of cosmic rays in the atmosphere. By observing zenith angle and energy of the particles produced by the neutrinos in single ring events in Super-Kamiokande, it became apparent that the muon neutrino (νμ) undergoes oscillations. During the oscillations, ν μ changes into another kind of neutrino, which can be either the tau neutrino (ντ) or a sterile neutrino (ν s). In addition, a small component of νe is possible but not considered here. With the standard single ring analysis, using two-flavor oscillations without matter effects, it was hard to discriminate between these two possibilities because, while νs doesn't interact at all and ν τ does, interactions of ντ don't produce a significant single ring signal. Due to the large mass of the taon (τ), charged current interactions of ντ are sup...

  4. Biomedical image understanding methods and applications

    CERN Document Server

    Lim, Joo-Hwee; Xiong, Wei

    2015-01-01

    A comprehensive guide to understanding and interpreting digital images in medical and functional applications Biomedical Image Understanding focuses on image understanding and semantic interpretation, with clear introductions to related concepts, in-depth theoretical analysis, and detailed descriptions of important biomedical applications. It covers image processing, image filtering, enhancement, de-noising, restoration, and reconstruction; image segmentation and feature extraction; registration; clustering, pattern classification, and data fusion. With contributions from ex

  5. Imaging technologies in oilfield applications

    Institute of Scientific and Technical Information of China (English)

    XIE C.G.; NORTH R.; WILT M.; ZHANG P.; DENACLARA H.; LEVESQUE C.

    2005-01-01

    In this paper, we describe some recent imaging technologies developed by Schlumberger for oilfield downhole multiphase flow production logging (PL) and cross-well electromagnetic (EM) survey applications. FloScan Imager (FSITM) has been introduced as a 3-phase oil/gas/water flow PL tool for deviated and horizontal wells. FSI sensors can map fluid velocity and holdup profiles along a vertical diameter of the wellbore at every survey depth, enabling a robust estimate of the individual phase flow rates in complex flow regimes. The cross-well EM survey is based on cross-borehole induction logging technique and provides resistivity distribution at a reservoir scale. It is a useful tool for reservoir management and is most effective in dynamic fields where fluid saturations are variable in time and space. The tool can be used to identify (water or steam) flooded and bypassed regions. By monitoring changes in the resistivity spatial distribution with time, cross-well EM survey is very effective at mapping inter-well temperature and structure. Some field examples are shown for both FloScan Imager PL tool and cross-well resistivity imaging survey.

  6. Tachyonic Cherenkov emission from Jupiter's radio electrons

    International Nuclear Information System (INIS)

    Tachyonic Cherenkov radiation from inertial relativistic electrons in the Jovian radiation belts is studied. The tachyonic modes are coupled to a frequency-dependent permeability tensor and admit a negative mass-square, rendering them superluminal and dispersive. The superluminal radiation field can be cast into Maxwellian form, using 3D field strengths and inductions, and the spectral densities of tachyonic Cherenkov radiation are derived. The negative mass-square gives rise to a longitudinal flux component. A spectral fit to Jupiter's radio spectrum, inferred from ground-based observations and the Cassini 2001 fly-by, is performed with tachyonic Cherenkov flux densities averaged over a thermal electron population.

  7. PyFACT: Python and FITS analysis for Cherenkov telescopes

    Science.gov (United States)

    Raue, Martin; Deil, Christoph

    2012-12-01

    Ground-based very-high energy (VHE; E>100 GeV) gamma-ray astronomy is growing from being conducted by small teams in closed collaborations into a full-fledged branch of astronomy with open observatories. This is best illustrated by the number of known sources: it increased by one order of magnitude in the past ten years, from 10 in the year 2000 to more than 100 in 2010. It is expected that this trend will continue with the next-generation instrument Cherenkov Telescope Array (CTA). This transformation has a profound impact on the data format and analysis of Imaging Atmospheric Cherenkov Telescopes (IACTs). Up to now, IACT data analysis was an internal task performed by specialists with no public access to the data or software. In the future, a large community of VHE astronomers from different scientific topics should be enabled to work with the data. Ease of use, compatibility, and integration with existing astronomy standards and tools will be key. In this contribution, a collection of Python tools for the analysis of data in FITS format (PyFACT; Python and FITS Analysis for Cherenkov Telescopes) is presented, which connects with existing tools like xspec, sherpa, and ds9. The package is available as open source (https://github.com/mraue/pyfact, comments and contributions welcome). Advantages of the chosen ansatz are discussed and implications for future observatories and data archival are presented.

  8. Color imaging fundamentals and applications

    CERN Document Server

    Reinhard, Erik; Oguz Akyuz, Ahmet; Johnson, Garrett

    2008-01-01

    This book provides the reader with an understanding of what color is, where color comes from, and how color can be used correctly in many different applications. The authors first treat the physics of light and its interaction with matter at the atomic level, so that the origins of color can be appreciated. The intimate relationship between energy levels, orbital states, and electromagnetic waves helps to explain why diamonds shimmer, rubies are red, and the feathers of the Blue Jay are blue. Then, color theory is explained from its origin to the current state of the art, including image captu

  9. Cooperative quasi-Cherenkov radiation

    CERN Document Server

    Anishchenko, S V

    2014-01-01

    We study the features of cooperative parametric (quasi-Cherenkov) radiation arising when initially unmodulated electron (positron) bunches pass through a crystal (natural or artificial) under the conditions of dynamical diffraction of electromagnetic waves in the presence of shot noise. A detailed numerical analysis is given for cooperative THz radiation in artificial crystals. The radiation intensity above 200~MW$/$cm$^2$ is obtained in simulations. In two- and three-wave diffraction cases, the peak intensity of cooperative radiation emitted at small and large angles to particle velocity is investigated as a function of the particle number in an electron bunch. The peak radiation intensity appeared to increase monotonically until saturation is achieved. At saturation, the shot noise causes strong fluctuations in the intensity of cooperative parametric radiation. It is shown that the duration of radiation pulses can be much longer than the particle flight time through the crystal. This enables a thorough expe...

  10. INTENSITY INTERFEROMETRY WITH CHERENKOV TELESCOPES

    Directory of Open Access Journals (Sweden)

    D. B. Kieda

    2010-01-01

    Full Text Available Se discuten las capacidades de arreglos de interferometría de intensidad estelar (SII que se pueden construir usando la siguiente generación de arreglos de telescopios de Cherenkov de imágenes de aire (IACTs. Estos arreglos de IACT tendrán un gran diámetro de - 100 m (> 8 m de re ectores ópticos, ofreciendo cerca de 5000 líneas de base interferométricas, extendiéndose a partir de 50 m a más que 1000 m. La implementación del SII en arreglos de IACT permitirán imágenes de alta resolución (< 0:1 mas en anchos de banda cortos (bandas B/V, que son óptimas para el estudio de estrellas calientes.

  11. Development of a SiPM Camera for a Schwarzschild-Couder Cherenkov Telescope for the Cherenkov Telescope Array

    CERN Document Server

    Otte, A N; Dickinson, H.; Funk, S.; Jogler, T.; Johnson, C.A.; Karn, P.; Meagher, K.; Naoya, H.; Nguyen, T.; Okumura, A.; Santander, M.; Sapozhnikov, L.; Stier, A.; Tajima, H.; Tibaldo, L.; Vandenbroucke, J.; Wakely, S.; Weinstein, A.; Williams, D.A.

    2015-01-01

    We present the development of a novel 11328 pixel silicon photomultiplier (SiPM) camera for use with a ground-based Cherenkov telescope with Schwarzschild-Couder optics as a possible medium-sized telescope for the Cherenkov Telescope Array (CTA). The finely pixelated camera samples air-shower images with more than twice the optical resolution of cameras that are used in current Cherenkov telescopes. Advantages of the higher resolution will be a better event reconstruction yielding improved background suppression and angular resolution of the reconstructed gamma-ray events, which is crucial in morphology studies of, for example, Galactic particle accelerators and the search for gamma-ray halos around extragalactic sources. Packing such a large number of pixels into an area of only half a square meter and having a fast readout directly attached to the back of the sensors is a challenging task. For the prototype camera development, SiPMs from Hamamatsu with through silicon via (TSV) technology are used. We give ...

  12. Neutron Detection via the Cherenkov Effect

    Energy Technology Data Exchange (ETDEWEB)

    Bell, Zane W [ORNL; Boatner, Lynn A [ORNL

    2010-01-01

    We have incorporated neutron-absorbing elements in transparent, nonscintillating glasses and used the Cherenkov effect to convert neutron-induced beta-gamma radiation directly into light. Use of the Cherenkov effect requires glasses with a high index of refraction (to lower the threshold and increase the number of Cherenkov photons) and neutron absorbers resulting in radioactive products emitting high-energy beta or gamma radiation. In this paper, we present a brief description of the requirements for developing efficient Cherenkov-based neutron detectors, show the results of measurements of the response of representative samples to thermal and fast neutron fluxes, and give the results of a calculation of the expected response of a detector to a moderated fission spectrum.

  13. Neutron Detection via the Cherenkov Effect

    Energy Technology Data Exchange (ETDEWEB)

    Bell, Zane W [ORNL; Boatner, Lynn A [ORNL

    2008-01-01

    We have incorporated neutron-absorbing elements in transparent, non-scintillating glasses and used the Cherenkov effect to convert neutron-induced beta-gamma radiation directly into light. Use of the Cherenkov effect requires glasses with a high index of refraction (to lower the threshold and increase the number of Cherenkov photons), and neutron absorbers resulting in radioactive products emitting high-energy beta or gamma radiation. In this paper, we present a brief description of the requirements for developing efficient Cherenkov-based neutron detectors, show the results of measurements of the response of representative samples to a thermal neutron flux, and give the results of a calculation of the expected response of a detector to a moderated fission spectrum.

  14. A facility to evaluate the focusing performance of mirrors for Cherenkov Telescopes

    CERN Document Server

    Canestrari, Rodolfo; Bonnoli, Giacomo; Farisato, Giancarlo; Lessio, Luigi; Rodeghiero, Gabriele; Spiga, Rossella; Toso, Giorgio; Pareschi, Giovanni

    2015-01-01

    With the advent of the imaging atmospheric Cherenkov technique in late 1980's, ground-based observations of Very High-Energy gamma rays came into reality. Since the first source detected at TeV energies in 1989 by Whipple, the number of high energy gamma-ray sources has rapidly grown up to more than 150 thanks to the second generation experiments like MAGIC, H.E.S.S. and VERITAS. The Cherenkov Telescope Array observatory is the next generation of Imaging Atmospheric Cherenkov Telescopes, with at least 10 times higher sensitivity than current instruments. Cherenkov Telescopes have to be equipped with optical dishes of large diameter -- in general based on segmented mirrors -- with typical angular resolution of a few arc-minutes. To evaluate the mirror's quality specific metrological systems are required that possibly take into account the environmental conditions in which typically Cherenkov telescopes operate (in open air without dome protection). For this purpose a new facility for the characterization of mi...

  15. A quartz Cherenkov detector for polarimetry at the ILC

    International Nuclear Information System (INIS)

    At the proposed International Linear Collider (ILC), the use of polarised electron and positron beams is a key ingredient of the physics program. A measurement of the polarisation with a yet unprecedented precision of δP/P=0.25% is required. To achieve this, Compton polarimeter measurements in front of and behind the collision point are foreseen. In this thesis, a novel concept for a detector for ILC polarimetry is introduced to eliminate one of the dominating systematics limiting the previous best measurement of beam polarisation: a detector using quartz as Cherenkov medium could increase the tolerance against non-linear photodetector responses. The high refractive index of quartz results in a higher Cherenkov light yield compared to conventional Cherenkov gases. This could allow single-peak resolution in the Cherenkov photon spectra produced by the Compton electrons at the polarimeters. The detailed simulation studies presented in this work imply that such single-peak resolution is possible. Considerations for the choice of a suitable detector geometry are discussed. A four-channel prototype has been constructed and successfully operated in a first testbeam campaign at the DESY testbeam, confirming simulation predictions. Although further studies have to be considered to quantify all aspects of the detector response, the findings of the analysis of the data from the first testbeam are promising with regards to reaching the desired light yield. In the final part of this thesis, the application of a detector concept allowing single-peak resolution to the polarisation measurement at the ILC is examined. Two of the main sources of systematic uncertainties on the polarimeter measurements are detector non-linearities and misalignments. The performance of the suggested quartz detector concept in Monte Carlo studies promises a control of these systematics which meets the precision requirements for ILC polarimetry.

  16. Neutron imaging and applications a reference for the imaging community

    CERN Document Server

    McGreevy, Robert L; Bilheux, Hassina Z

    2009-01-01

    Offers an introduction to the basics of neutron beam production in addition to the wide scope of techniques that enhance imaging application capabilities. This title features a section that describes imaging single grains in polycrystalline materials, neutron imaging of geological materials and other materials science and engineering areas.

  17. Measurements of Cherenkov Photons with Silicon Photomultipliers

    CERN Document Server

    Korpar, S; Chagani, H; Dolenec, R; Hara, K; Iijima, T; Krizan, P; Nishida, S; Pestotnik, R; Stanovnik, A

    2008-01-01

    A novel photon detector, the Silicon Photomultiplier (SiPM), has been tested in proximity focusing Ring Imaging Cherenkov (RICH) counters that were exposed to cosmic-ray particles in Ljubljana, and a 2 GeV electron beam at the KEK research facility. This type of RICH detector is a candidate for the particle identification detector upgrade of the BELLE detector at the KEK B-factory, for which the use of SiPMs, microchannel plate photomultiplier tubes or hybrid avalanche photodetectors, rather than traditional Photomultiplier Tubes (PMTs) is essential due to the presence of high magnetic fields. In both experiments, SiPMs are found to compare favourably with PMTs, with higher photon detection rates per unit area. Through the use of hemispherical and truncated pyramid light guides to concentrate photons onto the active surface area, the light yield increases significantly. An estimate of the contribution to dark noise from false coincidences between SiPMs in an array is also presented.

  18. Design optimization of the proximity focusing RICH with dual aerogel radiator using a maximum-likelihood analysis of Cherenkov rings

    Science.gov (United States)

    Pestotnik, R.; Križan, P.; Korpar, S.; Iijima, T.

    2008-09-01

    The use of a sequence of aerogel radiators with different refractive indices in a proximity focusing Cherenkov ring imaging detector has been shown to improve the resolution of the Cherenkov angle. In order to obtain further information on the capabilities of such a detector, a maximum-likelihood analysis has been performed on simulated data, with the simulation being appropriate for the upgraded Belle detector. The results show that by using a sequence of two aerogel layers with different refractive indices, the K/π separation efficiency is improved in the kinematic region above 3 GeV/ c. In the low momentum region, the focusing configuration (with n1 and n2 chosen such that the Cherenkov rings from different aerogel layers at 4 GeV/ c overlap) shows a better performance than the defocusing one (where the two Cherenkov rings are well separated).

  19. Measurement of Cherenkov photons by SiPMs with light guides

    Energy Technology Data Exchange (ETDEWEB)

    Korpar, S. [Faculty of Chemistry and Chemical Engineering, University of Maribor (Slovenia); J. Stefan Institute, Ljubljana (Slovenia)], E-mail: samo.korpar@ijs.si; Chagani, H.; Dolenec, R. [J. Stefan Institute, Ljubljana (Slovenia); Hara, K.; Iijima, T. [Nagoya University, Nagoya (Japan); Krizan, P. [J. Stefan Institute, Ljubljana (Slovenia); Faculty of Mathematics and Physics, University of Ljubljana (Slovenia); Mazuka, Y. [Nagoya University, Nagoya (Japan); Pestotnik, R. [J. Stefan Institute, Ljubljana (Slovenia); Stanovnik, A. [J. Stefan Institute, Ljubljana (Slovenia); Faculty of Electrical Engineering, University of Ljubljana (Slovenia); Yamaoka, M. [Nagoya University, Nagoya (Japan)

    2009-10-21

    Silicon Photomultipliers (SiPMs) are attractive photon detectors for Ring Imaging Cherenkov (RICH) counters inside large magnetic spectrometers due to their insensitivity to magnetic fields. We have investigated the possibilities offered by these new photon detectors in a cosmic ray test set-up. Cherenkov photons emitted by cosmic ray particles in an aerogel radiator have been detected with silicon photomultipliers for the first time. Estimates and tests show how light concentrators may improve the detection efficiency, thus showing promise for a SiPM based RICH detector. The optimum shape for these light guides is investigated.

  20. Layout design studies for medium-sized telescopes within the Cherenkov Telescope Array

    CERN Document Server

    Hassan, T; Nieto, D; Wood, M

    2015-01-01

    The Cherenkov Telescope Array (CTA) is an international project for a next-generation ground-based gamma-ray observatory. CTA, conceived as an array of tens of imaging atmospheric Cherenkov telescopes, comprising small, medium and large-size telescopes, is aiming to improve on the sensitivity of current-generation experiments by an order of magnitude and provide energy coverage from 20 GeV to more than 300 TeV. In this study we explore how the medium-sized telescopes layout design and composition impacts the overall CTA performance by analyzing Monte Carlo simulations including Davies-Cotton and Schwarzschild-Couder medium-sized telescopes.

  1. Prototyping the graphical user interface for the operator of the Cherenkov Telescope Array

    CERN Document Server

    Sadeh, Iftach; Schwarz, Joseph; Pietriga, Emmanuel

    2016-01-01

    The Cherenkov Telescope Array (CTA) is a planned gamma-ray observatory. CTA will incorporate about 100 imaging atmospheric Cherenkov telescopes (IACTs) at a Southern site, and about 20 in the North. Previous IACT experiments have used up to five telescopes. Subsequently, the design of a graphical user interface (GUI) for the operator of CTA involves new challenges. We present a GUI prototype, the concept for which is being developed in collaboration with experts from the field of Human-Computer Interaction. The prototype is based on Web technology; it incorporates a Python web server, Web Sockets and graphics generated with the d3.js Javascript library.

  2. Video-rate optical dosimetry and dynamic visualization of IMRT and VMAT treatment plans in water using Cherenkov radiation

    Energy Technology Data Exchange (ETDEWEB)

    Glaser, Adam K., E-mail: Adam.K.Glaser@dartmouth.edu, E-mail: Brian.W.Pogue@dartmouth.edu; Andreozzi, Jacqueline M.; Davis, Scott C. [Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755 (United States); Zhang, Rongxiao [Department of Physics and Astronomy, Dartmouth College, Hanover, New Hampshire 03755 (United States); Pogue, Brian W., E-mail: Adam.K.Glaser@dartmouth.edu, E-mail: Brian.W.Pogue@dartmouth.edu [Department of Physics and Astronomy and Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755 (United States); Fox, Colleen J.; Gladstone, David J. [Norris Cotton Cancer Center, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03766 (United States)

    2014-06-15

    Purpose: A novel technique for optical dosimetry of dynamic intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) plans was investigated for the first time by capturing images of the induced Cherenkov radiation in water. Methods: A high-sensitivity, intensified CCD camera (ICCD) was configured to acquire a two-dimensional (2D) projection image of the Cherenkov radiation induced by IMRT and VMAT plans, based on the Task Group 119 (TG-119) C-Shape geometry. Plans were generated using the Varian Eclipse treatment planning system (TPS) and delivered using 6 MV x-rays from a Varian TrueBeam Linear Accelerator (Linac) incident on a water tank doped with the fluorophore quinine sulfate. The ICCD acquisition was gated to the Linac target trigger pulse to reduce background light artifacts, read out for a single radiation pulse, and binned to a resolution of 512 × 512 pixels. The resulting videos were analyzed temporally for various regions of interest (ROI) covering the planning target volume (PTV) and organ at risk (OAR), and summed to obtain an overall light intensity distribution, which was compared to the expected dose distribution from the TPS using a gamma-index analysis. Results: The chosen camera settings resulted in 23.5 frames per second dosimetry videos. Temporal intensity plots of the PTV and OAR ROIs confirmed the preferential delivery of dose to the PTV versus the OAR, and the gamma analysis yielded 95.9% and 96.2% agreement between the experimentally captured Cherenkov light distribution and expected TPS dose distribution based upon a 3%/3 mm dose difference and distance-to-agreement criterion for the IMRT and VMAT plans, respectively. Conclusions: The results from this initial study demonstrate the first documented use of Cherenkov radiation for video-rate optical dosimetry of dynamic IMRT and VMAT treatment plans. The proposed modality has several potential advantages over alternative methods including the real

  3. Video-rate optical dosimetry and dynamic visualization of IMRT and VMAT treatment plans in water using Cherenkov radiation

    International Nuclear Information System (INIS)

    Purpose: A novel technique for optical dosimetry of dynamic intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) plans was investigated for the first time by capturing images of the induced Cherenkov radiation in water. Methods: A high-sensitivity, intensified CCD camera (ICCD) was configured to acquire a two-dimensional (2D) projection image of the Cherenkov radiation induced by IMRT and VMAT plans, based on the Task Group 119 (TG-119) C-Shape geometry. Plans were generated using the Varian Eclipse treatment planning system (TPS) and delivered using 6 MV x-rays from a Varian TrueBeam Linear Accelerator (Linac) incident on a water tank doped with the fluorophore quinine sulfate. The ICCD acquisition was gated to the Linac target trigger pulse to reduce background light artifacts, read out for a single radiation pulse, and binned to a resolution of 512 × 512 pixels. The resulting videos were analyzed temporally for various regions of interest (ROI) covering the planning target volume (PTV) and organ at risk (OAR), and summed to obtain an overall light intensity distribution, which was compared to the expected dose distribution from the TPS using a gamma-index analysis. Results: The chosen camera settings resulted in 23.5 frames per second dosimetry videos. Temporal intensity plots of the PTV and OAR ROIs confirmed the preferential delivery of dose to the PTV versus the OAR, and the gamma analysis yielded 95.9% and 96.2% agreement between the experimentally captured Cherenkov light distribution and expected TPS dose distribution based upon a 3%/3 mm dose difference and distance-to-agreement criterion for the IMRT and VMAT plans, respectively. Conclusions: The results from this initial study demonstrate the first documented use of Cherenkov radiation for video-rate optical dosimetry of dynamic IMRT and VMAT treatment plans. The proposed modality has several potential advantages over alternative methods including the real

  4. Quantum calculation of the Vavilov-Cherenkov radiation by twisted electrons

    Science.gov (United States)

    Ivanov, I. P.; Serbo, V. G.; Zaytsev, V. A.

    2016-05-01

    We present a detailed quantum electrodynamical description of Vavilov-Cherenkov radiation emitted by a relativistic twisted electron in the transparent medium. Simple expressions for the spectral and spectral-angular distributions as well as for the polarization properties of the emitted radiation are obtained. Unlike the plane-wave case, the twisted electron produces radiation within the annular angular region, with enhancement towards its boundaries. Additionally, the emitted photons can have linear polarization not only in the scattering plane but also in the orthogonal direction. We find that the Vavilov-Cherenkov radiation emitted by an electron in a superposition of two vortex states exhibits a strong azimuthal asymmetry. Thus, the Vavilov-Cherenkov radiation offers itself as a convenient diagnostic tool of such electrons and complements the traditional microscopic imaging.

  5. Influence of aerosols from biomass burning on the spectral analysis of Cherenkov telescopes

    CERN Document Server

    Reyes, R de los; Bernloehr, K; Krueger, P; Deil, C; Gast, H; Kosack, K; Marandon, V

    2013-01-01

    During the last decade, imaging atmospheric Cherenkov telescopes (IACTs) have proven themselves as astronomical detectors in the very-high-energy (VHE; E>0.1 TeV) regime. The IACT technique observes the VHE photons indirectly, using the Earth's atmosphere as a calorimeter. Much of the calibration of Cherenkov telescope experiments is done using Monte Carlo simulations of the air shower development, Cherenkov radiation and detector, assuming certain models for the atmospheric conditions. Any deviation of the real conditions during observations from the assumed atmospheric model will result in a wrong reconstruction of the primary gamma-ray energy and the resulting source spectra. During eight years of observations, the High Energy Stereoscopic System (H.E.S.S.) has experienced periodic natural as well as anthropogenic variations of the atmospheric transparency due to aerosols created by biomass burning. In order to identify data that have been taken under such long-term reductions in atmospheric transparency, ...

  6. Quantum calculation of the Vavilov-Cherenkov radiation by twisted electrons

    CERN Document Server

    Ivanov, I P; Zaytsev, V A

    2016-01-01

    We present the detailed quantum electrodynamical description of Vavilov-Cherenkov radiation emitted by a relativistic twisted electron in the transparent medium. Simple expressions for the spectral and spectral-angular distributions as well as for the polarization properties of the emitted radiation are obtained. Unlike the plane-wave case, the twisted electron produces radiation within the annular angular region, with enhancement towards its boundaries. Additionally, the emitted photons can have linear polarization not only in the scattering plane but also in the orthogonal direction. We find that the Vavilov-Cherenkov radiation emitted by an electron in a superposition of two vortex states exhibits a strong azimuthal asymmetry. Thus, the Vavilov-Cherenkov radiation offers itself as a convenient diagnostic tool of such electrons and complements the traditional microscopic imaging.

  7. Image Sensors in Security and Medical Applications

    OpenAIRE

    Artyomov, Evgeny; Fish, Alexander; Yadid-Pecht, Orly

    2007-01-01

    This paper briefly reviews CMOS image sensor technology and its utilization in security and medical applications. The role and future trends of image sensors in each of the applications are discussed. To provide the reader deeper understanding of the technology aspects the paper concentrates on the selected applications such as surveillance, biometrics, capsule endoscopy and artificial retina. The reasons for concentrating on these applications are due to their importance in our d...

  8. Applications Of Image Processing In Criminalistics

    Science.gov (United States)

    Krile, Thomas F.; Walkup, John F.; Barsallo, Adonis; Olimb, Hal; Tarng, Jaw-Horng

    1987-01-01

    A review of some basic image processing techniques for enhancement and restoration of images is given. Both digital and optical approaches are discussed. Fingerprint images are used as examples to illustrate the various processing techniques and their potential applications in criminalistics.

  9. Fuzzy image processing and applications with Matlab

    CERN Document Server

    Chaira, Tamalika

    2009-01-01

    In contrast to classical image analysis methods that employ ""crisp"" mathematics, fuzzy set techniques provide an elegant foundation and a set of rich methodologies for diverse image-processing tasks. However, a solid understanding of fuzzy processing requires a firm grasp of essential principles and background knowledge.Fuzzy Image Processing and Applications with MATLAB® presents the integral science and essential mathematics behind this exciting and dynamic branch of image processing, which is becoming increasingly important to applications in areas such as remote sensing, medical imaging,

  10. Medical imaging technology reviews and computational applications

    CERN Document Server

    Dewi, Dyah

    2015-01-01

    This book presents the latest research findings and reviews in the field of medical imaging technology, covering ultrasound diagnostics approaches for detecting osteoarthritis, breast carcinoma and cardiovascular conditions, image guided biopsy and segmentation techniques for detecting lung cancer, image fusion, and simulating fluid flows for cardiovascular applications. It offers a useful guide for students, lecturers and professional researchers in the fields of biomedical engineering and image processing.

  11. The Cherenkov Radiation for Non-Trivial Systems; La Radiacion Cherenkov en Sistemas No Triviales

    Energy Technology Data Exchange (ETDEWEB)

    Grau Carles, A.

    2002-07-01

    The charge pathways and the dielectric properties of the medium are two essential aspects to be considered in the study of the emission of Cherenkov radiation. We described the evolution of the Cherenkov wavefront when the charges follow circular or helical pathways. Also we derive expressions for the refractive Index in different transparent media (solid, liquid or gas), focusing our attention on optically active plasmas. The optical analogies between the plasma and the birefringent crystals is studied in detail. Finally, we list some examples of plasmas, which can be considered emitters of Cherenkov radiation. (Author) 52 refs.

  12. Spectral dependence of angular distribution halfwidths of Vavilov-Cherenkov radiation

    International Nuclear Information System (INIS)

    Angular distributions of Vavilov-Cherenkov radiation have been measured. This radiaiton is excited during 210 keV electron propagation in a mica 2.5 mm thick target in a spectral range from 2500 up to 5000 A. A formula for diffraction halfwidth of angular distribution has been derived, its applicability limits are pointed out. Experimental halfwidth agrees with the calculated ones. The deviation of angular distribution maximum from Vavilov-Cherenkov radiation angle is analyzed. This deviation is due to radiator boundaries and multiple scattering of electrons

  13. Combined complex Doppler and Cherenkov effect in left-handed metamaterials

    CERN Document Server

    Ziemkiewicz, David

    2015-01-01

    We derive the formula of the complex Doppler shift in a two-dimensional, dispersive metamaterial and we show that a moving, monochromatic radiation source generates multiple frequency modes. The role of the group velocity is stressed and the Doppler shifted radiation field exhibits features of the Cherenkov effect. The presented theory is also applicable to the case of a moving, nonoscillating charge and explains many peculiar characteristics of the Cherenkov radiation in lefthanded metamaterials such as the backward direction of power emission, the constant radiation angle and the lack of velocity threshold.

  14. All-fiber femtosecond Cherenkov radiation source

    OpenAIRE

    Liu, Xiaomin; Lægsgaard, Jesper; Møller, Uffe; Tu, Haohua; Boppart, Stephen A.; Turchinovich, Dmitry

    2012-01-01

    An all-fiber femtosecond source of spectrally isolated Cherenkov radiation is reported, to the best of our knowledge, for the first time. Using a monolithic, self-starting femtosecond Yb-doped fiber laser as the pump source and the combination of photonic crystal fibers as the wave-conversion medium, we demonstrate milliwatt-level, stable, and tunable Cherenkov radiation at visible wavelengths 580–630 nm, with pulse duration of sub-160-fs, and the 3 dB spectral bandwidth not exceeding 36 nm. ...

  15. Flipping photons backward: reversed Cherenkov radiation

    Directory of Open Access Journals (Sweden)

    Hongsheng Chen

    2011-01-01

    Full Text Available Charged particles moving faster than light in a medium produce Cherenkov radiation. In traditional, positive index-of-refraction materials this radiation travels forward. Metamaterials, with negative indices of refraction, flip the radiation backward. This readily separates it from the particles, providing higher flexibility in photon manipulation and is useful for particle identification and counting. Here we review recent advances in reversed Cherenkov radiation research, including the first demonstration of backward emission. We also discuss the potential for developing new types of devices, such as ones that pierce invisibility cloaks.

  16. Application of image fusion techniques in DSA

    Science.gov (United States)

    Ye, Feng; Wu, Jian; Cui, Zhiming; Xu, Jing

    2007-12-01

    Digital subtraction angiography (DSA) is an important technology in both medical diagnoses and interposal therapy, which can eliminate the interferential background and give prominence to blood vessels by computer processing. After contrast material is injected into an artery or vein, a physician produces fluoroscopic images. Using these digitized images, a computer subtracts the image made with contrast material from a series of post injection images made without background information. By analyzing the characteristics of DSA medical images, this paper provides a solution of image fusion which is in allusion to the application of DSA subtraction. We fuse the images of angiogram and subtraction, in order to obtain the new image which has more data information. The image that fused by wavelet transform can display the blood vessels and background information clearly, and medical experts gave high score on the effect of it.

  17. Medical image informatics infrastructure design and applications.

    Science.gov (United States)

    Huang, H K; Wong, S T; Pietka, E

    1997-01-01

    Picture archiving and communication systems (PACS) is a system integration of multimodality images and health information systems designed for improving the operation of a radiology department. As it evolves, PACS becomes a hospital image document management system with a voluminous image and related data file repository. A medical image informatics infrastructure can be designed to take advantage of existing data, providing PACS with add-on value for health care service, research, and education. A medical image informatics infrastructure (MIII) consists of the following components: medical images and associated data (including PACS database), image processing, data/knowledge base management, visualization, graphic user interface, communication networking, and application oriented software. This paper describes these components and their logical connection, and illustrates some applications based on the concept of the MIII. PMID:9509399

  18. On-site mirror facet condensation measurements for the Cherenkov Telescope Array

    Science.gov (United States)

    Dipold, J.; Medina, M. C.; García, B.; Rasztocky, E.; Mancilla, A.; Maya, J.; Larrarte, J. J.; de Souza, V.

    2016-09-01

    The Imaging Atmospheric Cherenkov Technique (IACT) has provided very important discoveries in Very High Energy (VHE) γ-ray astronomy for the last two decades, being exploited mainly by experiments such as H.E.S.S., MAGIC and VERITAS. The same technique will be used by the next generation of γ-ray telescopes, Cherenkov Telescope Array - CTA, which is conceived to be an Observatory composed by two arrays strategically placed in both hemispheres, one in the Northern and one in the Southern. Each site will consist of several tens of Cherenkov telescopes of different sizes and will be equipped with about 10000 m2 of reflective surface. Because of its large size, the reflector of a Cherenkov telescope is composed of many individual mirror facets. Cherenkov telescopes operate without any protective system from weather conditions therefore it is important to understand how the reflective surfaces behave under different environmental conditions. This paper describes a study of the behavior of the mirrors in the presence of water vapor condensation. The operational time of a telescope is reduced by the presence of condensation on the mirror surface, therefore, to control and to monitor the formation of condensation is an important issue for IACT observatories. We developed a method based on pictures of the mirrors to identify the areas with water vapor condensation. The method is presented here and we use it to estimate the time and area two mirrors had condensation when exposed to the environmental conditions in the Argentinean site. The study presented here shows important guidelines in the selection procedure of mirror technologies and shows an innovative monitoring tool to be used in future Cherenkov telescopes.

  19. Sparse microwave imaging: Principles and applications

    Institute of Scientific and Technical Information of China (English)

    ZHANG BingChen; HONG Wen; WU YiRong

    2012-01-01

    This paper provides principles and applications of the sparse microwave imaging theory and technology.Synthetic aperture radar (SAR) is an important method of modern remote sensing.During decades microwave imaging technology has achieved remarkable progress in the system performance of microwave imaging technology,and at the same time encountered increasing complexity in system implementation.The sparse microwave imaging introduces the sparse signal processing theory to radar imaging to obtain new theory,new system and new methodology of microwave imaging.Based on classical SAR imaging model and fundamental theories of sparse signal processing,we can derive the model of sparse microwave imaging,which is a sparse measurement and recovery problem and can be solved with various algorithms.There exist several fundamental points that must be considered in the efforts of applying sparse signal processing to radar imaging,including sparse representation,measurement matrix construction,unambiguity reconstruction and performance evaluation.Based on these considerations,the sparse signal processing could be successfully applied to radar imaging,and achieve benefits in several aspects,including improvement of image quality,reduction of data amount for sparse scene and enhancement of system performance.The sparse signal processing has also been applied in several specific radar imaging applications.

  20. Principle and applications of terahertz molecular imaging.

    Science.gov (United States)

    Son, Joo-Hiuk

    2013-05-31

    The principle, characteristics and applications of molecular imaging with terahertz electromagnetic waves are reviewed herein. The terahertz molecular imaging (TMI) technique uses nanoparticle probes to achieve dramatically enhanced sensitivity compared with that of conventional terahertz imaging. Surface plasmons, induced around the nanoparticles, raise the temperature of water in biological cells, and the temperature-dependent changes in the optical properties of water, which are large in the terahertz range, are measured differentially by terahertz waves. TMI has been applied to cancer diagnosis and nanoparticle drug delivery imaging. The technique is also compared with magnetic resonance imaging by using a dual-modality nanoparticle probe.

  1. Photoacoustic lifetime imaging and its biomedical applications

    Science.gov (United States)

    Shao, Qi

    Even though oxygen plays a crucial role in body function and cancer biology, methods of measuring oxygen level in tissue are all limited. The current gold standard relies on an invasive electrode for only single-point reading at a time. The photoacoustic lifetime imaging (PALI) approach overcomes these major limitations by applying photoacoustic probing to oxygen-sensitive optical transient absorption. The capability of assessing oxygen distribution is demonstrated by imaging tumor hypoxia in a small animal model, and monitoring changes of tissue oxygen induced by external modulations. Proposed applications of this imaging technique includes imaging-guided photodynamic therapy (PDT) and activatable probes for molecular imaging.

  2. Image Mining Techniques and Applications.

    OpenAIRE

    Deepika Kishor Nagthane

    2013-01-01

    Digitization in every sector leads to the growth of digital data in a tremendous amount. Digital data are not only available in the form of text but it is also available in the form of images, audio and video. Decision making people in every field like business, public sector, hospital, etc. are trying to get useful and implicit information from the already existing digital data bases. Image mining is the concept used to extract implicit and useful data from images stored in the large data ba...

  3. Development of a custom on-line ultrasonic vapour analyzer and flow meter for the ATLAS inner detector, with application to Cherenkov and gaseous charged particle detectors

    OpenAIRE

    Alhrooba, M.; Batesb, R.; Degeorged, C.; Deterree, C.; DiGirolamoc, B.; Doubekf, M.; Favrec, G.; Godlewskib, J.; Hallewellg, G.; Hasiba, A.; Katuninh, S.; Langeving, N.; Battistinc, M.; Lombardc, D.; Mathieug, M.

    2015-01-01

    Precision sound velocity measurements can simultaneously determine binary gas composition and flow. We have developed an analyzer with custom microcontroller-based electronics, currently used in the ATLAS Detector Control System, with numerous potential applications. Three instruments monitor C3F8 and CO2 coolant leak rates into the nitrogen envelopes of the ATLAS silicon microstrip and Pixel detectors. Two further instruments will aid operation of the new thermosiphon coolant recirculator: o...

  4. Progress on Cherenkov Reconstruction in MICE

    CERN Document Server

    Kaplan, Daniel M; Rajaram, Durga; Winter, Miles; Cremaldi, Lucien; Sanders, David; Summers, Don

    2016-01-01

    Two beamline Cherenkov detectors (Ckov-a,-b) support particle identification in the MICE beamline. Electrons and high-momentum muons and pions can be identified with good efficiency. We report on the Ckov-a,-b performance in detecting pions and muons with MICE Step I data and derive an upper limit on the pion contamination in the standard MICE muon beam.

  5. Fundamental and exotic physics with Cherenkov telescopes

    Energy Technology Data Exchange (ETDEWEB)

    De Angelis, A., E-mail: alessandro.de.angelis@cern.c [Dipartimento di Fisica dell' Universita di Udine and INFN, Udine (Italy); De Lotto, B. [Dipartimento di Fisica dell' Universita di Udine and INFN, Udine (Italy); Roncadelli, M. [INFN Pavia (Italy)

    2011-02-21

    The detection of high-energy {gamma} rays from astrophysical sources, using the Fermi/LAT detector and in the very-high-energy limit the Cherenkov telescopes MAGIC, H.E.S.S. and VERITAS, can provide tests of fundamental physics with unprecedented sensitivity, and possibly allows to probe new and exotic scenarios.

  6. Prior image constrained image reconstruction in emerging computed tomography applications

    Science.gov (United States)

    Brunner, Stephen T.

    Advances have been made in computed tomography (CT), especially in the past five years, by incorporating prior images into the image reconstruction process. In this dissertation, we investigate prior image constrained image reconstruction in three emerging CT applications: dual-energy CT, multi-energy photon-counting CT, and cone-beam CT in image-guided radiation therapy. First, we investigate the application of Prior Image Constrained Compressed Sensing (PICCS) in dual-energy CT, which has been called "one of the hottest research areas in CT." Phantom and animal studies are conducted using a state-of-the-art 64-slice GE Discovery 750 HD CT scanner to investigate the extent to which PICCS can enable radiation dose reduction in material density and virtual monochromatic imaging. Second, we extend the application of PICCS from dual-energy CT to multi-energy photon-counting CT, which has been called "one of the 12 topics in CT to be critical in the next decade." Numerical simulations are conducted to generate multiple energy bin images for a photon-counting CT acquisition and to investigate the extent to which PICCS can enable radiation dose efficiency improvement. Third, we investigate the performance of a newly proposed prior image constrained scatter correction technique to correct scatter-induced shading artifacts in cone-beam CT, which, when used in image-guided radiation therapy procedures, can assist in patient localization, and potentially, dose verification and adaptive radiation therapy. Phantom studies are conducted using a Varian 2100 EX system with an on-board imager to investigate the extent to which the prior image constrained scatter correction technique can mitigate scatter-induced shading artifacts in cone-beam CT. Results show that these prior image constrained image reconstruction techniques can reduce radiation dose in dual-energy CT by 50% in phantom and animal studies in material density and virtual monochromatic imaging, can lead to radiation

  7. Computer vision for biomedical image applications. Proceedings

    International Nuclear Information System (INIS)

    This book constitutes the refereed proceedings of the First International Workshop on Computer Vision for Biomedical Image Applications: Current Techniques and Future Trends, CVBIA 2005, held in Beijing, China, in October 2005 within the scope of ICCV 20. (orig.)

  8. Atmospheric multiple scattering of fluorescence and Cherenkov light emitted by extensive air showers

    OpenAIRE

    Pekala, J.; Homola, P.; Wilczynska, B.; Wilczynski, H.

    2009-01-01

    Atmospheric scattering of light emitted by an air shower not only attenuates direct fluorescence light from the shower, but also contributes to the observed shower light. So far only direct and singly-scattered Cherenkov photons have been taken into account in routine analyses of the observed optical image of air showers. In this paper a Monte Carlo method of evaluating the contribution of multiply scattered light to the optical air shower image is presented, as well as results of simulations...

  9. INFN Camera demonstrator for the Cherenkov Telescope Array

    CERN Document Server

    Ambrosi, G; Aramo, C.; Bertucci, B.; Bissaldi, E.; Bitossi, M.; Brasolin, S.; Busetto, G.; Carosi, R.; Catalanotti, S.; Ciocci, M.A.; Consoletti, R.; Da Vela, P.; Dazzi, F.; De Angelis, A.; De Lotto, B.; de Palma, F.; Desiante, R.; Di Girolamo, T.; Di Giulio, C.; Doro, M.; D'Urso, D.; Ferraro, G.; Ferrarotto, F.; Gargano, F.; Giglietto, N.; Giordano, F.; Giraudo, G.; Iacovacci, M.; Ionica, M.; Iori, M.; Longo, F.; Mariotti, M.; Mastroianni, S.; Minuti, M.; Morselli, A.; Paoletti, R.; Pauletta, G.; Rando, R.; Fernandez, G. Rodriguez; Rugliancich, A.; Simone, D.; Stella, C.; Tonachini, A.; Vallania, P.; Valore, L.; Vagelli, V.; Verzi, V.; Vigorito, C.

    2015-01-01

    The Cherenkov Telescope Array is a world-wide project for a new generation of ground-based Cherenkov telescopes of the Imaging class with the aim of exploring the highest energy region of the electromagnetic spectrum. With two planned arrays, one for each hemisphere, it will guarantee a good sky coverage in the energy range from a few tens of GeV to hundreds of TeV, with improved angular resolution and a sensitivity in the TeV energy region better by one order of magnitude than the currently operating arrays. In order to cover this wide energy range, three different telescope types are envisaged, with different mirror sizes and focal plane features. In particular, for the highest energies a possible design is a dual-mirror Schwarzschild-Couder optical scheme, with a compact focal plane. A silicon photomultiplier (SiPM) based camera is being proposed as a solution to match the dimensions of the pixel (angular size of ~ 0.17 degrees). INFN is developing a camera demonstrator made by 9 Photo Sensor Modules (PSMs...

  10. Open-structure composite mirrors for the Cherenkov Telescope Array

    CERN Document Server

    Dyrda, Michal; Niemiec, Jacek; Stodulski, Marek

    2013-01-01

    The Cherenkov Telescope Array (CTA) Observatory for high-energy gamma-ray astronomy will comprise several tens of imaging atmospheric Cherenkov telescopes (IACTs) of different size with a total reflective area of about 10,000 m$^2$. Here we present a new technology for the production of IACT mirrors that has been developed in the Institute of Nuclear Physics PAS in Krakow, Poland. An open-structure composite mirror consists of a rigid flat sandwich support structure and cast-in-mould spherical epoxy resin layer. To this layer a thin glass sheet complete with optical coating is cold-slumped to provide the spherical reflective layer of the mirror. The main components of the sandwich support structure are two flat float glass panels inter spaced with V-shape aluminum spacers of equal length. The sandwich support structure is open, thus enabling good cooling and ventilation of the mirror. A special arrangement of the aluminum spacers also prohibits water being trapped inside. The open-structure technology thus re...

  11. NECTAr: New electronics for the Cherenkov Telescope Array

    Energy Technology Data Exchange (ETDEWEB)

    Vorobiov, S., E-mail: vorobiov@lpta.in2p3.f [LPTA, Universite Montpellier II and IN2P3/CNRS, Montpellier (France); Bolmont, J.; Corona, P. [LPNHE, Universite Paris VI and IN2P3/CNRS, Paris (France); Delagnes, E. [IRFU/DSM/CEA, Saclay, Gif-sur-Yvette (France); Feinstein, F. [LPTA, Universite Montpellier II and IN2P3/CNRS, Montpellier (France); Gascon, D. [ICC-UB, Universitat Barcelona, Barcelona (Spain); Glicenstein, J.-F. [IRFU/DSM/CEA, Saclay, Gif-sur-Yvette (France); Naumann, C.L.; Nayman, P. [LPNHE, Universite Paris VI and IN2P3/CNRS, Paris (France); Sanuy, A. [ICC-UB, Universitat Barcelona, Barcelona (Spain); Toussenel, F.; Vincent, P. [LPNHE, Universite Paris VI and IN2P3/CNRS, Paris (France)

    2011-05-21

    The European astroparticle physics community aims to design and build the next generation array of Imaging Atmospheric Cherenkov Telescopes (IACTs), that will benefit from the experience of the existing H.E.S.S. and MAGIC detectors, and further expand the very-high energy astronomy domain. In order to gain an order of magnitude in sensitivity in the 10 GeV to >100TeV range, the Cherenkov Telescope Array (CTA) will employ 50-100 mirrors of various sizes equipped with 1000-4000 channels per camera, to be compared with the 6000 channels of the final H.E.S.S. array. A 3-year program, started in 2009, aims to build and test a demonstrator module of a generic CTA camera. We present here the NECTAr design of front-end electronics for the CTA, adapted to the trigger and data acquisition of a large IACTs array, with simple production and maintenance. Cost and camera performances are optimized by maximizing integration of the front-end electronics (amplifiers, fast analog samplers, ADCs) in an ASIC, achieving several GS/s and a few {mu}s readout dead-time. We present preliminary results and extrapolated performances from Monte Carlo simulations.

  12. A Compact High Energy Camera for the Cherenkov Telescope Array

    CERN Document Server

    Daniel, M K; Berge, D; Buckley, J; Chadwick, P M; Cotter, G; Funk, S; Greenshaw, T; Hidaka, N; Hinton, J; Lapington, J; Markoff, S; Moore, P; Nolan, S; Ohm, S; Okumura, A; Ross, D; Sapozhnikov, L; Schmoll, J; Sutcliffe, P; Sykes, J; Tajima, H; Varner, G S; Vandenbroucke, J; Vink, J; Williams, D

    2013-01-01

    The Compact High Energy Camera (CHEC) is a camera-development project involving UK, US, Japanese and Dutch institutes for the dual-mirror Small-Sized Telescopes (SST-2M) of the Cherenkov Telescope Array (CTA). Two CHEC prototypes, based on different photosensors are funded and will be assembled and tested in the UK over the next ~18 months. CHEC is designed to record flashes of Cherenkov light lasting from a few to a hundred nanoseconds, with typical RMS image width and length of ~0.2 x 1.0 degrees, and has a 9 degree field of view. The physical camera geometry is dictated by the telescope optics: a curved focal surface with radius of curvature 1m and diameter ~35cm is required. CHEC is designed to work with both the ASTRI and GATE SST-2M telescope structures and will include an internal LED flasher system for calibration. The first CHEC prototype will be based on multi-anode photomultipliers (MAPMs) and the second on silicon photomultipliers (SiPMs or MPPCs). The first prototype will soon be installed on the...

  13. Image processing applications in NDE

    Energy Technology Data Exchange (ETDEWEB)

    Morris, R.A.

    1980-01-01

    Nondestructive examination (NDE) can be defined as a technique or collection of techniques that permits one to determine some property of a material or object without damaging the object. There are a large number of such techniques and most of them use visual imaging in one form or another. They vary from holographic interferometry where displacements under stress are measured to the visual inspection of an objects surface to detect cracks after penetrant has been applied. The use of image processing techniques on the images produced by NDE is relatively new and can be divided into three general categories: classical image enhancement; mensuration techniques; and quantitative sensitometry. An example is discussed of how image processing techniques are used to nondestructively and destructively test the product throughout its life cycle. The product that will be followed is the microballoon target used in the laser fusion program. The laser target is a small (50 to 100 ..mu..m - dia) glass sphere with typical wall thickness of 0.5 to 6 ..mu..m. The sphere may be used as is or may be given a number of coatings of any number of materials. The beads are mass produced by the millions and the first nondestructive test is to separate the obviously bad beads (broken or incomplete) from the good ones. After this has been done, the good beads must be inspected for spherocity and wall thickness uniformity. The microradiography of the glass, uncoated bead is performed on a specially designed low-energy x-ray machine. The beads are mounted in a special jig and placed on a Kodak high resolution plate in a vacuum chamber that contains the x-ray source. The x-ray image is made with an energy less that 2 keV and the resulting images are then inspected at a magnification of 500 to 1000X. Some typical results are presented.

  14. CMOS Image Sensors for High Speed Applications

    Directory of Open Access Journals (Sweden)

    M. Jamal Deen

    2009-01-01

    Full Text Available Recent advances in deep submicron CMOS technologies and improved pixel designs have enabled CMOS-based imagers to surpass charge-coupled devices (CCD imaging technology for mainstream applications. The parallel outputs that CMOS imagers can offer, in addition to complete camera-on-a-chip solutions due to being fabricated in standard CMOS technologies, result in compelling advantages in speed and system throughput. Since there is a practical limit on the minimum pixel size (4~5 μm due to limitations in the optics, CMOS technology scaling can allow for an increased number of transistors to be integrated into the pixel to improve both detection and signal processing. Such smart pixels truly show the potential of CMOS technology for imaging applications allowing CMOS imagers to achieve the image quality and global shuttering performance necessary to meet the demands of ultrahigh-speed applications. In this paper, a review of CMOS-based high-speed imager design is presented and the various implementations that target ultrahigh-speed imaging are described. This work also discusses the design, layout and simulation results of an ultrahigh acquisition rate CMOS active-pixel sensor imager that can take 8 frames at a rate of more than a billion frames per second (fps.

  15. Development of a custom on-line ultrasonic vapour analyzer/flowmeter for the ATLAS inner detector, with application to gaseous tracking and Cherenkov detectors

    CERN Document Server

    Bates, R; Berry, S; Berthoud, J; Bitadze, A; Bonneau, P; Botelho-Direito, J; Bousson, N; Boyd, G; Bozza, G; Da Riva, E; Degeorge, C; DiGirolamo, B; Doubek, M; Godlewski, J; Hallewell, G; Katunin, S; Lombard, D; Mathieu, M; McMahon, S; Nagai, K; Perez-Rodriguez, E; Rossi, C; Rozanov, A; Vacek, V; Vitek, M; Zwalinski, L

    2013-01-01

    Precision sound velocity measurements can simultaneously determine binary gas composition and flow. We have developed an analyzer with custom electronics, currently in use in the ATLAS inner detector, with numerous potential applications. The instrument has demonstrated ~0.3% mixture precision for C3F8/C2F6 mixtures and < 10-4 resolution for N2/C3F8 mixtures. Moderate and high flow versions of the instrument have demonstrated flow resolutions of +/- 2% F.S. for flows up to 250 l.min-1, and +/- 1.9% F.S. for linear flow velocities up to 15 ms-1; the latter flow approaching that expected in the vapour return of the thermosiphon fluorocarbon coolant recirculator being built for the ATLAS silicon tracker.

  16. Development of a custom on-line ultrasonic vapour analyzer and flow meter for the ATLAS inner detector, with application to Cherenkov and gaseous charged particle detectors

    Science.gov (United States)

    Alhroob, M.; Bates, R.; Battistin, M.; Berry, S.; Bitadze, A.; Bonneau, P.; Bousson, N.; Boyd, G.; Bozza, G.; Crespo-Lopez, O.; Degeorge, C.; Deterre, C.; DiGirolamo, B.; Doubek, M.; Favre, G.; Godlewski, J.; Hallewell, G.; Hasib, A.; Katunin, S.; Langevin, N.; Lombard, D.; Mathieu, M.; McMahon, S.; Nagai, K.; O'Rourke, A.; Pearson, B.; Robinson, D.; Rossi, C.; Rozanov, A.; Strauss, M.; Vacek, V.; Zwalinski, L.

    2015-03-01

    Precision sound velocity measurements can simultaneously determine binary gas composition and flow. We have developed an analyzer with custom microcontroller-based electronics, currently used in the ATLAS Detector Control System, with numerous potential applications. Three instruments monitor C3F8 and CO2 coolant leak rates into the nitrogen envelopes of the ATLAS silicon microstrip and Pixel detectors. Two further instruments will aid operation of the new thermosiphon coolant recirculator: one of these will monitor air leaks into the low pressure condenser while the other will measure return vapour flow along with C3F8/C2F6 blend composition, should blend operation be necessary to protect the ATLAS silicon tracker under increasing LHC luminosity. We describe these instruments and their electronics.

  17. Development of a custom on-line ultrasonic vapour analyzer/flowmeter for the ATLAS inner detector, with application to gaseous tracking and Cherenkov detectors

    Science.gov (United States)

    Bates, R.; Battistin, M.; Berry, S.; Berthoud, J.; Bitadze, A.; Bonneau, P.; Botelho-Direito, J.; Bousson, N.; Boyd, G.; Bozza, G.; Da Riva, E.; Degeorge, C.; DiGirolamo, B.; Doubek, M.; Godlewski, J.; Hallewell, G.; Katunin, S.; Lombard, D.; Mathieu, M.; McMahon, S.; Nagai, K.; Perez-Rodriguez, E.; Rossi, C.; Rozanov, A.; Vacek, V.; Vitek, M.; Zwalinski, L.

    2013-01-01

    Precision sound velocity measurements can simultaneously determine binary gas composition and flow. We have developed an analyzer with custom electronics, currently in use in the ATLAS inner detector, with numerous potential applications. The instrument has demonstrated ~ 0.3% mixture precision for C3F8/C2F6 mixtures and < 10-4 resolution for N2/C3F8 mixtures. Moderate and high flow versions of the instrument have demonstrated flow resolutions of ± 2% of full scale for flows up to 250 l min-1, and ± 1.9% of full scale for linear flow velocities up to 15 m s-1 the latter flow approaching that expected in the vapour return of the thermosiphon fluorocarbon coolant recirculator being built for the ATLAS silicon tracker.

  18. Infrared thermal imaging fundamentals, research and applications

    CERN Document Server

    Vollmer, Michael

    2011-01-01

    This richly illustrated hands-on guide is designed for researchers, teachers and practitioners. The huge selection of examples taken from science, basic teaching of physics, practical applications in industry and a variety of other disciplines spanning the range from medicine to volcano research allows readers to pick those that come closest to their own individual task at hand. Following a look at the fundamentals of IR thermal imaging, properties of the imaging systems, as well as basic and advanced methods, the book goes on to discuss IR imaging applications in teaching, research and indust

  19. Clinical applications of choroidal imaging technologies

    Directory of Open Access Journals (Sweden)

    Jay Chhablani

    2015-01-01

    Full Text Available Choroid supplies the major blood supply to the eye, especially the outer retinal structures. Its understanding has significantly improved with the advent of advanced imaging modalities such as enhanced depth imaging technique and the newer swept source optical coherence tomography. Recent literature reports the findings of choroidal changes, quantitative as well as qualitative, in various chorioretinal disorders. This review article describes applications of choroidal imaging in the management of common diseases such as age-related macular degeneration, high myopia, central serous chorioretinopathy, chorioretinal inflammatory diseases, and tumors. This article briefly discusses future directions in choroidal imaging including angiography.

  20. Image Processing Application on Graphics processors

    Directory of Open Access Journals (Sweden)

    Chouchene Marwa

    2014-04-01

    Full Text Available In this work, we introduce real time image processing techniques using modern programmable Graphic Processing Units GPU. GPU are SIMD (Single Instruction, Multiple Data device that is inherently data-parallel. By utilizing NVIDIA new GPU programming framework, “Compute Unified Device Architecture” CUDA as a computational resource, we realize significant acceleration in image processing algorithm computations. We show that a range of computer vision algorithms map readily to CUDA with significant performance gains. Specifically, we demonstrate the efficiency of our approach by a parallelization and optimization of image processing, Morphology applications and image integral.

  1. Magnetic imaging and its applications to materials

    CERN Document Server

    De Graef, Marc

    2000-01-01

    Volume 36 provides an extensive introduction to magnetic imaging,including theory and practice, utilizing a wide range of magnetic sensitive imaging methods. It also illustrates the applications of these modern experimental techniques together with imaging calculations to today's advanced magnetic materials. This book is geared towards the upper-level undergraduate students and entry-level graduate students majoring in physics or materials science who are interested in magnetic structure and magnetic imaging. Researchers involved in studying magnetic materials should alsofind the book usef

  2. Fundamentals and applications of neutron imaging (applications part 10). Applications of neutron imaging to medical field

    International Nuclear Information System (INIS)

    Described is the application of neutron (Nt) imaging in 3 objects, small animals and excised organs, odontology, and BNCT (boron Nt capture therapy). Nt radiography (NR) uses the fast and thermal Nt. For the former Nt, NR is done by transferring the permeation image on In-leaf to X-ray film or by direct imaging on nitro-cellulose film; and for the latter, by imaging on X-ray film through Gd-converter, by transfer of the image on In- or Dy-leaf to the film or by use of (BaFBr-Gd2O3) Nt imaging plate. NR in animals can image air-containing organs like the lung. For human excised organs, NR can give images of wet tissues in hard organs like malignant tumors in the bone due to a large and small Nt cross sections of H and Ca, respectively. Excised gallstones (cholesterol- and Ca-derived) have been subjected to NR. NR of the pancreatic cancer has been reported with fast Nt. Many studies of NR have been reported in odontology, involving animals', human normal, treated and prosthetic teeth. NR can give information different in nature from X-ray radiography and further development of NR in odontology is expected as one of nondestructive tests. In BNCT-related field, NCAR (NC autoradiography) has been applied for seeing the distribution of 10B in the tumor-bearing mouse given a B compound. Thermal and cold Nts are irradiated on the mouse whole body section and yielded (4He+7Li) radioactivity is detected by CR-39 plastic track detector undergone with various etching treatments. The distribution in the body and tumor can be observed by NCAR and by the recently-developed, versatile high speed image acquisition microscope, respectively. Micro-dosimetry on the CR-39 is thought possible by the latter microscope. (R.T.)

  3. Wavelength Shifters for Water Cherenkov Detectors

    CERN Document Server

    Dai, Xiongxin; Bellerive, Alain; Hargrove, Cliff; Sinclair, David; Mifflin, Cathy; Zhang Feng

    2008-01-01

    The light yield of a water-based Cherenkov detector can be significantly improved by adding a wavelength shifter. Wavelength shifter (WLS) molecules absorb ultraviolet photons and re-emit them at longer wavelengths where typical photomultiplier tubes are more sensitive. In this study, several wavelength shifter compounds are tested for possible deployment in the Sudbury Neutrino Observatory (SNO). Test results on optical properties and chemical compatibility for a few WLS candidates are reported; together with timing and gain measurements. A Monte Carlo simulation of the SNO detector response is used to estimate the total light gain with WLS. Finally, a cosmic ray Cherenkov detector was built to investigate the optical properties of WLS.

  4. Mirror Development for the Cherenkov Telescope Array

    CERN Document Server

    Förster, A; Baba, H; Bähr, J; Bonardi, A; Bonnoli, G; Brun, P; Canestrari, R; Chadwick, P; Chikawa, M; Carton, P -H; De Souza, V; Dipold, J; Doro, M; Durand, D; Dyrda, M; Giro, E; Glicenstein, J -F; Hanabata, Y; Hayashida, M; Hrabovski, M; Jeanney, C; Kagaya, M; Katagiri, H; Lessio, L; MANDAT, D; Mariotti, M; Medina, C; Michałowski, J; Micolon, P; Nakajima, D; Niemiec, J; Nozato, A; Palatka, M; Pareschi, G; Pech, M; Peyaud, B; Pühlhofer, G; Rataj, M; Rodeghiero, G; Rojas, G; Rousselle, J; Sakonaka, R; Schovanek, P; Seweryn, K; Schultz, C; Shu, S; Stinzing, F; Stodulski, M; Teshima, M; Travniczek, P; Van Eldik, C; Vassiliev, V; Wiśniewski, Ł; Wörnlein, A; Yoshida, T

    2013-01-01

    The Cherenkov Telescope Array (CTA) is a planned observatory for very-high energy gamma-ray astronomy. It will consist of several tens of telescopes of different sizes, with a total mirror area of up to 10,000 square meters. Most mirrors of current installations are either polished glass mirrors or diamond-turned aluminium mirrors, both labour intensive technologies. For CTA, several new technologies for a fast and cost-efficient production of light-weight and reliable mirror substrates have been developed and industrial pre-production has started for most of them. In addition, new or improved aluminium-based and dielectric surface coatings have been developed to increase the reflectance over the lifetime of the mirrors compared to those of current Cherenkov telescope instruments.

  5. Characterization of coherent Cherenkov radiation source

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, A.V.

    2015-01-21

    Engineering formulae for calculation of peak, and spectral brightness of resonant long-range wakefield extractor are given. It is shown that the brightness is dominated by beam density in the slow wave structure and antenna gain of the outcoupling. Far field radiation patterns and brightness of circular and high aspect ratio planar radiators are compared. A possibility to approach diffraction limited brightness is demonstrated. The role of group velocity in designing of the Cherenkov source is analyzed. The approach can be applied for design and characterization of various structure-dominated sources (e.g., wakefield extractors with gratings or dielectrics, or FEL-Cherenkov combined sources) radiating into a free space using an antenna (in microwave to sub-mm wave regions). The high group velocity structures can be also effective as energy dechirpers and for diagnostics of microbunched relativistic electron beams.

  6. Recent progress in silica aerogel Cherenkov radiator

    CERN Document Server

    Tabata, Makoto; Kawai, Hideyuki; Kubo, Masato; Sato, Takeshi

    2012-01-01

    In this paper, we present recent progress in the development of hydrophobic silica aerogel as a Cherenkov radiator. In addition to the conventional method, the recently developed pin-drying method for producing high-refractive-index aerogels with high transparency was studied in detail. Optical qualities and large tile handling for crack-free aerogels were investigated. Sufficient photons were detected from high-performance aerogels in a beam test.

  7. Study of TOF PET using Cherenkov light

    Science.gov (United States)

    Korpar, S.; Dolenec, R.; Križan, P.; Pestotnik, R.; Stanovnik, A.

    We report on measurements of coincident 511 keV annihilation photons via detection of Cherenkov radiation in PbF2 crystals attached to a microchannel plate photomultiplier. Back to back timing resolution has been studied with segmented crystals. The detection efficiency has also been measured and compared to the simulation results. We have also searched for the optimum radiator parameters by simulating timing resolution and effciency as a function of crystal thickness and transmission cut-off.

  8. QUEST: wide angle Cherenkov light measurements at EAS-TOP

    Science.gov (United States)

    EAS-Top Collaboration; Korosteleva, E. E.; Kuzmichev, L. A.; Prosin, V. V.; Lubsandorzhiev, B. K.

    Wide angle Cherenkov light detectors based upon the QUASAR-370 photo-multipliers have been installed on five Cherenkov telescopes of the EAS-TOP array to study the energy spectrum and composition of primary cosmic rays around the knee . The energy threshold of quasars array was close to that of EAS-TOP electromagnetic detectors array. The first results of joint analysis of Cherenkov and electromagnetic data together with the adequate CORSIKA simulation results are discussed.

  9. Roughness tolerances for Cherenkov telescope mirrors

    Science.gov (United States)

    Tayabaly, K.; Spiga, D.; Canestrari, R.; Bonnoli, G.; Lavagna, M.; Pareschi, G.

    2015-09-01

    The Cherenkov Telescope Array (CTA) is a forthcoming international ground-based observatory for very high-energy gamma rays. Its goal is to reach sensitivity five to ten times better than existing Cherenkov telescopes such as VERITAS, H.E.S.S. or MAGIC and extend the range of observation to energies down to few tens of GeV and beyond 100 TeV. To achieve this goal, an array of about 100 telescopes is required, meaning a total reflective surface of several thousands of square meters. Thence, the optimal technology used for CTA mirrors' manufacture should be both low-cost (~1000 euros/m2) and allow high optical performances over the 300-550 nm wavelength range. More exactly, a reflectivity higher than 85% and a PSF (Point Spread Function) diameter smaller than 1 mrad. Surface roughness can significantly contribute to PSF broadening and limit telescope performances. Fortunately, manufacturing techniques for mirrors are now available to keep the optical scattering well below the geometrically-predictable effect of figure errors. This paper determines first order surface finish tolerances based on a surface microroughness characterization campaign, using Phase Shift Interferometry. That allows us to compute the roughness contribution to Cherenkov telescope PSF. This study is performed for diverse mirror candidates (MAGIC-I and II, ASTRI, MST) varying in manufacture technologies, selected coating materials and taking into account the degradation over time due to environmental hazards.

  10. Detection of atmospheric Cherenkov radiation using solar heliostat mirrors

    CERN Document Server

    Ong, R A

    1996-01-01

    The gamma-ray energy region between 20 and 250 GeV is largely unexplored. Ground-based atmospheric Cherenkov detectors offer a possible way to explore this region, but large Cherenkov photon collection areas are needed to achieve low energy thresholds. This paper discusses the development of a Cherenkov detector using the heliostat mirrors of a solar power plant as the primary collector. As part of this development, we built a prototype detector consisting of four heliostat mirrors and used it to record atmospheric Cherenkov radiation produced in extensive air showers created by cosmic ray particles.

  11. Schwarzschild-Couder telescope for the Cherenkov Telescope Array: Development of the Optical System

    CERN Document Server

    Rousselle, Julien; Errando, Manel; Humensky, Brian; Mukherjee, Reshmi; Nieto, Daniel; Okumura, Akira; Vassiliev, Vladimir

    2013-01-01

    The CTA (Cherenkov Telescope Array) is the next generation ground-based experiment for very high-energy (VHE) gamma-ray observations. It will integrate several tens of imaging atmospheric Cherenkov telescopes (IACTs) with different apertures into a single astronomical instrument. The US part of the CTA collaboration has proposed and is developing a novel IACT design with a Schwarzschild-Couder (SC) aplanatic two mirror optical system. In comparison with the traditional single mirror Davies-Cotton IACT the SC telescope, by design, can accommodate a wide field-of-view, with significantly improved imaging resolution. In addition, the reduced plate scale of an SC telescope makes it compatible with highly integrated cameras assembled from silicon photo multipliers. In this submission we report on the status of the development of the SC optical system, which is part of the effort to construct a full-scale prototype telescope of this type at the Fred Lawrence Whipple Observatory in southern Arizona.

  12. Monte Carlo Studies of medium-size telescope designs for the Cherenkov Telescope Array

    CERN Document Server

    Wood, M; Dumm, J; Funk, S

    2015-01-01

    We present studies for optimizing the next generation of ground-based imaging atmospheric Cherenkov telescopes (IACTs). Results focus on mid-sized telescopes (MSTs) for CTA, detecting very high energy gamma rays in the energy range from a few hundred GeV to a few tens of TeV. We describe a novel, flexible detector Monte Carlo package, FAST (FAst Simulation for imaging air cherenkov Telescopes), that we use to simulate different array and telescope designs. The simulation is somewhat simplified to allow for efficient exploration over a large telescope design parameter space. We investigate a wide range of telescope performance parameters including optical resolution, camera pixel size, and light collection area. In order to ensure a comparison of the arrays at their maximum sensitivity, we analyze the simulations with the most sensitive techniques used in the field, such as maximum likelihood template reconstruction and boosted decision trees for background rejection. Choosing telescope design parameters repre...

  13. Photosensor Characterization for the Cherenkov Telescope Array: Silicon Photomultiplier versus Multi-Anode Photomultiplier Tube

    CERN Document Server

    Bouvier, Aurelien; Johnson, Caitlin; Kuznetsov, Andrey; Williams, David; Otte, Nepomuk; Strausbaugh, Robert; Hidaka, Naoya; Tajima, Hiroyasu; Hinton, Jim; White, Richard; Errando, Manel; Mukherjee, Reshmi

    2013-01-01

    Photomultiplier tube technology has been the photodetector of choice for the technique of imaging atmospheric Cherenkov telescopes since its birth more than 50 years ago. Recently, new types of photosensors are being contemplated for the next generation Cherenkov Telescope Array. It is envisioned that the array will be partly composed of telescopes using a Schwarzschild-Couder two mirror design never built before which has significantly improved optics. The camera of this novel optical design has a small plate scale which enables the use of compact photosensors. We present an extensive and detailed study of the two most promising devices being considered for this telescope design: the silicon photomultiplier and the multi-anode photomultiplier tube. We evaluated their most critical performance characteristics for imaging gamma-ray showers, and we present our results in a cohesive manner to clearly evaluate the advantages and disadvantages that both types of device have to offer in the context of GeV-TeV gamma...

  14. Experimental study of the atmospheric neutrino backgrounds for proton decay to positron and neutral pion searches in water Cherenkov detectors

    CERN Document Server

    Mine, S; Andringa, S; Aoki, S; Argyriades, J; Asakura, K; Ashie, R; Berghaus, F; Berns, H; Bhang, H; Blondel, A; Borghi, S; Bouchez, J; Burguet-Castell, J; Casper, D; Catala, J; Cavata, C; Cervera-Villanueva, Anselmo; Chen, S M; Cho, K O; Choi, J H; Dore, U; Espinal, X; Fechner, M; Fernández, E; Fujii, Y; Fukuda, Y; Gomez-Cadenas, J; Gran, R; Hara, T; Hasegawa, M; Hasegawa, T; Hayato, Y; Helmer, R L; Hiraide, K; Hosaka, J; Ichikawa, A K; Iinuma, M; Ikeda, A; Ishida, T; Ishihara, K; Ishii, T; Ishitsuka, M; Itow, Y; Iwashita, T; Jang, H I; Jeon, E J; Jeong, I S; Joo, K K; Jover, G; Jung, C K; Kajita, T; Kameda, J; Kaneyuki, K; Kato, I; Kearns, E; Kim, C O; Khabibullin, M; Khotjantsev, A; Kielczewska, D; Kim, J Y; Kim, S B; Kitching, P; Kobayashi, K; Kobayashi, T; Konaka, A; Koshio, Y; Kropp, W; Kudenko, Yu; Kuno, Y; Kurimoto, Y; Kutter, T; Learned, J; Likhoded, S; Lim, I T; Loverre, P F; Ludovici, L; Maesaka, H; Mallet, J; Mariani, C; Matsuno, S; Matveev, V; McConnel, K; McGrew, C; Mikheyev, S; Minamino, A; Mineev, O; Mitsuda, C; Miura, M; Moriguchi, Y; Moriyama, S; Nakadaira, T; Nakahata, M; Nakamura, K; Nakano, I; Nakaya, T; Nakayama, S; Namba, T; Nambu, R; Nawang, S; Nishikawa, K; Nitta, K; Nova, F; Novella, P; Obayashi, Y; Okada, A; Okumura, K; Oser, S M; Oyama, Y; Pac, M Y; Pierre, F; Rodríguez, A; Saji, C; Sakuda, M; Sánchez, F; Scholberg, K; Schroeter, R; Sekiguchi, M; Shiozawa, M; Shiraishi, K; Sitjes, G; Smy, M; Sobel, H; Sorel, M; Stone, J; Sulak, L; Suzuki, A; Suzuki, Y; Tada, M; Takahashi, T; Takenaga, Y; Takeuchi, Y; Taki, K; Takubo, Y; Tamura, N; Tanaka, M; Terri, R; T'Jampens, S; Tornero-Lopez, A; Totsuka, Y; Vagins, M; Whitehead, L; Walter, C W; Wang, W; Wilkes, R J; Yamada, S; Yamada, Y; Yamamoto, S; Yanagisawa, C; Yershov, N; Yokoyama, H; Yokoyama, M; Yoo, J; Yoshida, M; Zalipska, J

    2008-01-01

    The atmospheric neutrino background for proton decay to positron and neutral pion in ring imaging water Cherenkov detectors is studied with an artificial accelerator neutrino beam for the first time. In total, about 314,000 neutrino events corresponding to about 10 megaton-years of atmospheric neutrino interactions were collected by a 1,000 ton water Cherenkov detector (KT). The KT charged-current single neutral pion production data are well reproduced by simulation programs of neutrino and secondary hadronic interactions used in the Super-Kamiokande (SK) proton decay search. The obtained proton to positron and neutral pion background rate by the KT data for SK from the atmospheric neutrinos whose energies are below 3 GeV is about two per megaton-year. This result is also relevant to possible future, megaton-scale water Cherenkov detectors.

  15. Novel hemispheric image formation: concepts and applications

    Science.gov (United States)

    Thibault, Simon; Konen, Pierre; Roulet, Patrice; Villegas, Mathieu

    2008-04-01

    Panoramic and hemispheric lens technologies represent new and exciting opportunities in both imaging and projection systems. Such lenses offer intriguing applications for the transportation/automotive industry, in the protection of civilian and military areas, business. In this paper we describe a new optical design technique that provides a greater degree of freedom in producing a variety of hemispheric spatial light distribution areas. This innovative optical design strategy, of generating and controlling image mapping, has been successful in producing high-resolution imaging and projection systems. This success has subsequently generated increased interest in the high-resolution camera/projector and the concept of absolute measurement with high-resolution wide-angle lenses. The new technique described in this paper uses optimization techniques to improve the performance of a customized wide-angle lens optical system for a specific application. By adding a custom angle-to-pixel ratio at the optical design stage, this customized optical system provides ideal image coverage while reducing and optimizing signal processing. This novel image formation technique requires the development of new algorithms in order to view the panoramic image on a display without any residual distortion.

  16. Image Processing and its Military Applications

    Directory of Open Access Journals (Sweden)

    V. V.D. Shah

    1987-10-01

    Full Text Available One of the important breakthroughs, image processing is the stand alone, non-human image understanding system (IUS. The task of understanding images becomes monumental as one tries to define what understanding really is. Both pattern recognition and artificial intelligence are used in addition to traditional signal processing. Scene analysis procedures using edge and texture segmentation can be considered as the early stages of image understanding process. Symbolic representation and relationship grammers come at subsequent stages. Thus it is not reasonable to put a man into a loop of signal processing at certain sensors such as remotely piloted vehicles, satellites and spacecrafts. Consequently smart sensors and semi-automatic processes are being developed. Land remote sensing has been another important application of the image processing. With the introduction of programmes like Star Wars this particular application has gained a special importance from the Military's point of view. This paper provides an overview of digital image processing and explores the scope of the technology of remote sensing and IUSs from the Military's point of view. An example of the autonomous vehicle project now under progress in the US is described in detail to elucidate the impact of IUSs.

  17. Recent applications of hyperspectral imaging in microbiology.

    Science.gov (United States)

    Gowen, Aoife A; Feng, Yaoze; Gaston, Edurne; Valdramidis, Vasilis

    2015-05-01

    Hyperspectral chemical imaging (HSI) is a broad term encompassing spatially resolved spectral data obtained through a variety of modalities (e.g. Raman scattering, Fourier transform infrared microscopy, fluorescence and near-infrared chemical imaging). It goes beyond the capabilities of conventional imaging and spectroscopy by obtaining spatially resolved spectra from objects at spatial resolutions varying from the level of single cells up to macroscopic objects (e.g. foods). In tandem with recent developments in instrumentation and sampling protocols, applications of HSI in microbiology have increased rapidly. This article gives a brief overview of the fundamentals of HSI and a comprehensive review of applications of HSI in microbiology over the past 10 years. Technical challenges and future perspectives for these techniques are also discussed.

  18. An Innovative Workspace for The Cherenkov Telescope Array

    CERN Document Server

    Costa, Alessandro; Becchini, Ugo; Massimino, Piero; Riggi, Simone; Sanchez, David; Vitello, Fabio

    2016-01-01

    The Cherenkov Telescope Array (CTA) is an initiative to build the next generation, ground-based gamma-ray observatories. We present a prototype workspace developed at INAF that aims at providing innovative solutions for the CTA community. The workspace leverages open source technologies providing web access to a set of tools widely used by the CTA community. Two different user interaction models, connected to an authentication and authorization infrastructure, have been implemented in this workspace. The first one is a workflow management system accessed via a science gateway (based on the Liferay platform) and the second one is an interactive virtual desktop environment. The integrated workflow system allows to run applications used in astronomy and physics researches into distributed computing infrastructures (ranging from clusters to grids and clouds). The interactive desktop environment allows to use many software packages without any installation on local desktops exploiting their native graphical user i...

  19. Genitourinary imaging: Current and emerging applications

    Directory of Open Access Journals (Sweden)

    O′ Donoghue P

    2010-01-01

    Full Text Available This review discusses the current and emerging techniques in urinary tract imaging. Recent technical advances and novel discoveries make this an exciting but challenging time for urinary tract imaging. The first section describes the imaging of the adrenal gland which has made great strides in the last decade, the current major adrenal imaging modalities as well as new applications are discussed with particular attention to the role of imaging in the incidentally detected adrenal lesion. In the second section the role of ultrasound, computed tomography (CT and magnetic resonance (MR in evaluation of the renal tract are discussed with the new technical advances leading to earlier detection and characterization of renal lesions. Complementary to this is the emerging role of CT and MR urography in assessment of the urinary tract and bladder in contrast to the demise of plain film studies/intravenous urography. The role of CT angiography in assessment of the renal vasculature is also discussed. The third section discusses the role of prostate imaging in the diagnosis, staging and management of prostate cancer. Transrectal ultrasonography, can be used to guide biopsy, CT is frequently used in staging, with bone scintigraphy and positron emission tomography having roles in advanced disease. Currently, all imaging modalities, especially MR are evolving to improve disease detection and staging. The final section discusses the recently encountered adverse reaction of nephrogenic systemic fibrosis in patients post gadolinium-enhanced MRI and how to help prevent this adverse reaction.

  20. Genitourinary imaging: current and emerging applications.

    Science.gov (United States)

    O' Donoghue, P M; McSweeney, S E; Jhaveri, K

    2010-01-01

    This review discusses the current and emerging techniques in urinary tract imaging. Recent technical advances and novel discoveries make this an exciting but challenging time for urinary tract imaging. The first section describes the imaging of the adrenal gland which has made great strides in the last decade, the current major adrenal imaging modalities as well as new applications are discussed with particular attention to the role of imaging in the incidentally detected adrenal lesion. In the second section the role of ultrasound, computed tomography (CT) and magnetic resonance (MR) in evaluation of the renal tract are discussed with the new technical advances leading to earlier detection and characterization of renal lesions. Complementary to this is the emerging role of CT and MR urography in assessment of the urinary tract and bladder in contrast to the demise of plain film studies/intravenous urography. The role of CT angiography in assessment of the renal vasculature is also discussed. The third section discusses the role of prostate imaging in the diagnosis, staging and management of prostate cancer. Transrectal ultrasonography, can be used to guide biopsy, CT is frequently used in staging, with bone scintigraphy and positron emission tomography having roles in advanced disease. Currently, all imaging modalities, especially MR are evolving to improve disease detection and staging. The final section discusses the recently encountered adverse reaction of nephrogenic systemic fibrosis in patients post gadolinium-enhanced MRI and how to help prevent this adverse reaction.

  1. Applications of Imaging Flow Cytometry for Microalgae.

    Science.gov (United States)

    Hildebrand, Mark; Davis, Aubrey; Abbriano, Raffaela; Pugsley, Haley R; Traller, Jesse C; Smith, Sarah R; Shrestha, Roshan P; Cook, Orna; Sánchez-Alvarez, Eva L; Manandhar-Shrestha, Kalpana; Alderete, Benjamin

    2016-01-01

    The ability to image large numbers of cells at high resolution enhances flow cytometric analysis of cells and cell populations. In particular, the ability to image intracellular features adds a unique aspect to analyses, and can enable correlation between molecular phenomena resulting in alterations in cellular phenotype. Unicellular microalgae are amenable to high-throughput analysis to capture the diversity of cell types in natural samples, or diverse cellular responses in clonal populations, especially using imaging cytometry. Using examples from our laboratory, we review applications of imaging cytometry, specifically using an Amnis(®) ImageStream(®)X instrument, to characterize photosynthetic microalgae. Some of these examples highlight advantages of imaging flow cytometry for certain research objectives, but we also include examples that would not necessarily require imaging and could be performed on a conventional cytometer to demonstrate other concepts in cytometric evaluation of microalgae. We demonstrate the value of these approaches for (1) analysis of populations, (2) documentation of cellular features, and (3) analysis of gene expression.

  2. Multimodal interaction in image and video applications

    CERN Document Server

    Sappa, Angel D

    2013-01-01

    Traditional Pattern Recognition (PR) and Computer Vision (CV) technologies have mainly focused on full automation, even though full automation often proves elusive or unnatural in many applications, where the technology is expected to assist rather than replace the human agents. However, not all the problems can be automatically solved being the human interaction the only way to tackle those applications. Recently, multimodal human interaction has become an important field of increasing interest in the research community. Advanced man-machine interfaces with high cognitive capabilities are a hot research topic that aims at solving challenging problems in image and video applications. Actually, the idea of computer interactive systems was already proposed on the early stages of computer science. Nowadays, the ubiquity of image sensors together with the ever-increasing computing performance has open new and challenging opportunities for research in multimodal human interaction. This book aims to show how existi...

  3. Recent results on aerogel development for use in Cherenkov counters

    CERN Document Server

    Danilyuk, A F; Savelieva, M D; Bobrovnikov, V S; Buzykaev, A R; Kravchenko, E A; Lavrov, A V; Onuchin, A P

    2002-01-01

    Synthesis of silica aerogel for Cherenkov counters is being studied for more than 10 years at the Boreskov Institute of Catalysis in collaboration with the Budker Institute of Nuclear Physics. Index of refraction, light scattering length and light absorption length are optical characteristics which determine the quality of aerogel Cherenkov counter. These parameters were measured for the aerogel produced. The results are presented.

  4. Poster — Thur Eve — 18: Cherenkov Emission By High-Energy Radiation Therapy Beams: A Characterization Study

    Energy Technology Data Exchange (ETDEWEB)

    Zlateva, Y.; El Naqa, I. [Medical Physics Unit, Department of Oncology, McGill University, Montreal, QC (Canada); Quitoriano, N. [Department of Mining and Materials Engineering McGill University, Montreal, QC (Canada)

    2014-08-15

    We investigate Cherenkov emission (CE) by radiotherapy beams via radiation dose-versus-CE correlation analyses, CE detection optimization by means of a spectral shift towards the near-infrared (NIR) window of biological tissue, and comparison of CE to on-board MV imaging. Dose-CE correlation was investigated via simulation and experiment. A Monte Carlo (MC) CE simulator was designed using Geant4. Experimental phantoms include: water; tissue-simulating phantom composed of water, Intralipid®, and beef blood; plastic phantom with solid water insert. The detector system comprises an optical fiber and diffraction-grating spectrometer incorporating a front/back-illuminated CCD. The NIR shift was carried out with CdSe/ZnS quantum dots (QDs), emitting at (650±10) nm. CE and MV images were acquired with a CMOS camera and electronic portal imaging device. MC and experimental studies indicate a strong linear dose-CE correlation (Pearson coefficient > 0.99). CE by an 18-MeV beam was effectively NIR-shifted in water and a tissue-simulating phantom, exhibiting a significant increase at 650 nm for QD depths up to 10 mm. CE images exhibited relative contrast superior to MV images by a factor of 30. Our work supports the potential for application of CE in radiotherapy online imaging for patient setup and treatment verification, since CE is intrinsic to the beam and non-ionizing and QDs can be used to improve CE detectability, potentially yielding image quality superior to MV imaging for the case of low-density-variability, low-optical-attenuation materials (ex: breast/oropharynx). Ongoing work involves microenvironment functionalization of QDs and application of multi-channel spectrometry for simultaneous acquisition of dosimetric and tumor oxygenation signals.

  5. Uncooled LWIR imaging: applications and market analysis

    Science.gov (United States)

    Takasawa, Satomi

    2015-05-01

    The evolution of infrared (IR) imaging sensor technology for defense market has played an important role in developing commercial market, as dual use of the technology has expanded. In particular, technologies of both reduction in pixel pitch and vacuum package have drastically evolved in the area of uncooled Long-Wave IR (LWIR; 8-14 μm wavelength region) imaging sensor, increasing opportunity to create new applications. From the macroscopic point of view, the uncooled LWIR imaging market is divided into two areas. One is a high-end market where uncooled LWIR imaging sensor with sensitivity as close to that of cooled one as possible is required, while the other is a low-end market which is promoted by miniaturization and reduction in price. Especially, in the latter case, approaches towards consumer market have recently appeared, such as applications of uncooled LWIR imaging sensors to night visions for automobiles and smart phones. The appearance of such a kind of commodity surely changes existing business models. Further technological innovation is necessary for creating consumer market, and there will be a room for other companies treating components and materials such as lens materials and getter materials and so on to enter into the consumer market.

  6. Performance of a hybrid photon detector prototype with electrostatic cross-focussing and integrated silicon Pixel readout for Cherenkov ring detection

    CERN Document Server

    Alemi, M; Bibby, J H; Campbell, M; Duane, A; Easo, S; Gys, Thierry; Halley, A W; Piedigrossi, D; Puertolas, D; Rosso, E; Simmons, B; Snoeys, W; Websdale, David M; Wotton, S A; Wyllie, Ken H

    1999-01-01

    We report on the first test beam performance of a hybrid photon detector prototype, using binary readout electronics, intended for use in the ring imaging Cherenkov detectors of the LHCb experiment at the CERN Large Hadron Collider. The photon detector is based on a cross-focussed image intensifier tube geometry. The anode consists of a silicon pixel array bump-bonded to a binary readout chip with matching pixel electronics. The detector has been installed in a quarter-scale prototype vessel of the LHCb ring imaging Cherenkov system. Focussed ring images produced by 120 GeV/c negative pions traversing an air radiator have been recorded. The observed light yield and Cherenkov angle resolution are discussed.

  7. TARGET: toward a solution for the readout electronics of the Cherenkov Telescope Array

    CERN Document Server

    Tibaldo, L; Albert, A M; Funk, S; Kawashima, T; Kraus, M; Okumura, A; Sapozhnikov, L; Tajima, H; Varner, G S; Wu, T; Zink, A

    2015-01-01

    TARGET is an application specific integrated circuit (ASIC) designed to read out signals recorded by the photosensors in cameras of very-high-energy gamma-ray telescopes exploiting the imaging of Cherenkov radiation from atmospheric showers. TARGET capabilities include sampling at a high rate (typically 1 GSample/s), digitization, and triggering on the sum of four adjacent pixels. The small size, large number of channels read out per ASIC (16), low cost per channel, and deep buffer for trigger latency (~16 $\\mu$s at 1 GSample/s) make TARGET ideally suited for the readout in systems with a large number of telescopes instrumented with compact photosensors like multi-anode or silicon photomultipliers combined with dual-mirror optics. The possible advantages of such systems are better sensitivity, a larger field of view, and improved angular resolution. The two latest generations of TARGET ASICs, TARGET 5 and TARGET 7, are soon to be used for the first time in two prototypes of small-sized and medium-sized dual-m...

  8. Applications Of Binary Image Analysis Techniques

    Science.gov (United States)

    Tropf, H.; Enderle, E.; Kammerer, H. P.

    1983-10-01

    After discussing the conditions where binary image analysis techniques can be used, three new applications of the fast binary image analysis system S.A.M. (Sensorsystem for Automation and Measurement) are reported: (1) The human view direction is measured at TV frame rate while the subject's head is free movable. (2) Industrial parts hanging on a moving conveyor are classified prior to spray painting by robot. (3) In automotive wheel assembly, the eccentricity of the wheel is minimized by turning the tyre relative to the rim in order to balance the eccentricity of the components.

  9. The GERDA Muon Veto Cherenkov Detector

    International Nuclear Information System (INIS)

    The GERDA experiment is designed to examine 0νββ of 76Ge with a lifetime of 1026 years. To reach the goal of 10-3 background events/(keV*kg*year), several background reduction techniques will be used. Cosmic muons can produce background in form of particles and radioactivity. To reject them a muon veto system, using the water tank surrounding the GERDA cryostat as an active Cherenkov veto, is built up. The design, simulations and the construction of this veto are described in the poster. (author)

  10. The Cherenkov Telescope Array Large Size Telescope

    CERN Document Server

    Ambrosi, G; Baba, H; Bamba, A; Barceló, M; de Almeida, U Barres; Barrio, J A; Bigas, O Blanch; Boix, J; Brunetti, L; Carmona, E; Chabanne, E; Chikawa, M; Colin, P; Conteras, J L; Cortina, J; Dazzi, F; Deangelis, A; Deleglise, G; Delgado, C; Díaz, C; Dubois, F; Fiasson, A; Fink, D; Fouque, N; Freixas, L; Fruck, C; Gadola, A; García, R; Gascon, D; Geffroy, N; Giglietto, N; Giordano, F; Grañena, F; Gunji, S; Hagiwara, R; Hamer, N; Hanabata, Y; Hassan, T; Hatanaka, K; Haubold, T; Hayashida, M; Hermel, R; Herranz, D; Hirotani, K; Inoue, S; Inoue, Y; Ioka, K; Jablonski, C; Kagaya, M; Katagiri, H; Kishimoto, T; Kodani, K; Kohri, K; Konno, Y; Koyama, S; Kubo, H; Kushida, J; Lamanna, G; Flour, T Le; López-Moya, M; López, R; Lorenz, E; Majumdar, P; Manalaysay, A; Mariotti, M; Martínez, G; Martínez, M; Mazin, D; Miranda, J M; Mirzoyan, R; Monteiro, I; Moralejo, A; Murase, K; Nagataki, S; Nakajima, D; Nakamori, T; Nishijima, K; Noda, K; Nozato, A; Ohira, Y; Ohishi, M; Ohoka, H; Okumura, A; Orito, R; Panazol, J L; Paneque, D; Paoletti, R; Paredes, J M; Pauletta, G; Podkladkin, S; Prast, J; Rando, R; Reimann, O; Ribó, M; Rosier-Lees, S; Saito, K; Saito, T; Saito, Y; Sakaki, N; Sakonaka, R; Sanuy, A; Sasaki, H; Sawada, M; Scalzotto, V; Schultz, S; Schweizer, T; Shibata, T; Shu, S; Sieiro, J; Stamatescu, V; Steiner, S; Straumann, U; Sugawara, R; Tajima, H; Takami, H; Tanaka, S; Tanaka, M; Tejedor, L A; Terada, Y; Teshima, M; Totani, T; Ueno, H; Umehara, K; Vollhardt, A; Wagner, R; Wetteskind, H; Yamamoto, T; Yamazaki, R; Yoshida, A; Yoshida, T; Yoshikoshi, T

    2013-01-01

    The two arrays of the Very High Energy gamma-ray observatory Cherenkov Telescope Array (CTA) will include four Large Size Telescopes (LSTs) each with a 23 m diameter dish and 28 m focal distance. These telescopes will enable CTA to achieve a low-energy threshold of 20 GeV, which is critical for important studies in astrophysics, astroparticle physics and cosmology. This work presents the key specifications and performance of the current LST design in the light of the CTA scientific objectives.

  11. Cherenkov detector for beam quality measurement

    Science.gov (United States)

    Orfanelli, S.

    2016-07-01

    A new detector to measure the machine induced background at larger radii has been developed and installed in the CMS experiment at the LHC. It consists of forty modules, each comprising a quartz bar read out by a photomultiplier tube. Since Cherenkov radiation is emitted in a forward cone around the charged particle trajectory, these detectors can distinguish between the arrival directions of the machine induced background and the collision products. The back-end electronics consists of a uTCA readout with excellent time resolution. The installation in the CMS is described and first commissioning measurements with the LHC beams in Run II are presented.

  12. Gadolinium study for a water Cherenkov detector

    CERN Document Server

    Kibayashi, Atsuko

    2009-01-01

    Modification of large water Cherenkov detectors by addition of gadolinium has been proposed. The large cross section for neutron capture on Gd will greatly improve the sensitivity to antielectron neutrinos from supernovae and reactors. A five-year project to build and develop a prototype detector based on Super-Kamiokande (SK) has started. We are performing various studies, including a material soak test in Gd solution, light attenuation length measurements, purification system development, and neutron tagging efficiency measurements using SK data and a Geant4-based simulation. We present an overview of the project and the recent R&D results.

  13. Cherenkov radiation as a serendipitous phenomenon

    Science.gov (United States)

    Kadmensky, S. G.

    2015-05-01

    A brief account is given of P A Cherenkov's Voronezh years, a period during which the future Nobel laureate in physics attended school (in the village of Novaya Chigla near Voronezh) and studied at Voronezh State University. The history of the serendipitous discovery of the radiation which was to be named after him is described and its importance for modern science is discussed. Possible modern approaches are considered to explain — without using the concept of 'cold nuclear synthesis' — some other unexpected experimental results on the nonthermonuclear fusion of light nuclei stimulated by electron beams and by laser and gamma radiations.

  14. Modelling and study of the Cherenkov effect

    Energy Technology Data Exchange (ETDEWEB)

    Mishev, A. E-mail: libor.makovicka@pu-pm.univ-fcomte.fr; Duverger, E.; Makovicka, L.; Stamenov, J

    2001-06-01

    Studies at the Institute for Nuclear Research and Nuclear Energy particularly in regard to cosmic ray detection and construction of the Muonic Cherenkov telescope at the University of Blagoevgrad indicate a need for the development of a theoretical model based on observed phenomena and a refinement of this for detection system optimisation. This was introduced in the EGS4 code system. The first simulations consecrate on a number of different geometries of the water tank in total reflection. The model was compared with experimental data involving a {sup 60}Co gamma source and the telescope. (author)

  15. Active optics system of the ASTRI SST-2M prototype for the Cherenkov Telescope Array

    Science.gov (United States)

    Gardiol, Daniele; Capobianco, Gerardo; Fantinel, Daniela; Giro, Enrico; Lessio, Luigi; Loreggia, Davide; Rodeghiero, Gabriele; Russo, Federico; Volpicelli, Antonio C.

    2014-07-01

    ASTRI (Astrofisica con Specchi a Tecnologia Replicante Italiana) SST-2M is an end-to-end prototype of Small Size class of Telescope for the Cherenkov Telescope Array. It will apply a dual mirror configuration to Imaging Atmospheric Cherenkov Telescopes. The 18 segments composing the primary mirror (diameter 4.3 m) are equipped with an active optics system enabling optical re-alignment during telescope slew. The secondary mirror (diameter 1.8 m) can be moved along three degrees of freedom to perform focus and tilt corrections. We describe the kinematic model used to predict the system performance as well as the hardware and software design solution that will be implemented for optics control.

  16. First ground based measurement of atmospheric Cherenkov light from cosmic rays

    CERN Document Server

    Aharonian, F A; Bazer-Bachi, A R; Beilicke, M; Benbow, W; Berge, D; Bernlöhr, K; Boisson, C; Bolz, O; Borrel, V; Braun, I; Brion, E; Brown, A M; Buhler, R; Büsching, I; Carrigan, S; Chadwick, P M; Chounet, L M; Coignet, G; Cornils, R; Costamante, L; Degrange, B; Dickinson, H J; Djannati-Atai, A; O'Connor-Drury, L; Dubus, G; Egberts, K; Emmanoulopoulos, D; Espigat, P; Feinstein, F; Ferrero, E; Fiasson, A; Fontaine, G; Funk, Seb; Funk, S; Fussling, M; Gallant, Y A; Giebels, B; Glicenstein, J F; Glück, B; Goret, P; Hadjichristidis, C; Hauser, D; Hauser, M; Heinzelmann, G; Henri, G; Hermann, G; Hinton, J A; Hoffmann, A; Hofmann, W; Holleran, M; Hoppe, S; Horns, D; Jacholkowska, A; De Jager, O C; Kendziorra, E; Kerschhaggl, M; Khelifi, B; Komin, Nu; Konopelko, A; Kosack, K; Lamanna, G; Latham, I J; Le Gallou, R; Lemiere, A; Lemoine-Goumard, M; Lohse, T; Martin, J M; Martineau-Huynh, O; Marcowith, A; Masterson, C; Maurin, G; McComb, T J L; Moulin, E; De Naurois, Mathieu; Nedbal, D; Nolan, S J; Noutsos, A; Olive, J P; Orford, K J; Osborne, J L; Panter, M; Pelletier, G; Pita, S; Pühlhofer, G; Punch, M; Ranchon, S; Raubenheimer, B C; Raue, M; Rayner, S M; Reimer, A; Ripken, J; Rob, L; Rolland, L; Rosier-Lees, S; Rowell, G; Sahakian, V V; Santangelo, A; Sauge, L; Schlenker, S; Schlickeiser, R; Schroder, R; Schwanke, U; Schwarzburg, S; Schwemmer, S; Shalchi, A; Sol, H; Spangler, D; Spanier, F; Steenkamp, R; Stegmann, C; Superina, G; Tam, P H; Tavernet, J P; Terrier, R; Tluczykont, M; Van Eldik, C; Vasileiadis, G; Venter, C; Vialle, J P; Vincent, P; Völk, H J; Wagner, S J; Ward, M

    2007-01-01

    A recently proposed novel technique for the detection of cosmic rays with arrays of Imaging Atmospheric Cherenkov Telescopes is applied to data from the High Energy Stereoscopic System (H.E.S.S.). The method relies on the ground based detection of Cherenkov light emitted from the primary particle prior to its first interaction in the atmosphere. The charge of the primary particle (Z) can be estimated from the intensity of this light, since it is proportional to Z$^2$. Using H.E.S.S. data, an energy spectrum for cosmic-ray iron nuclei in the energy range 13--200 TeV is derived. The reconstructed spectrum is consistent with previous direct measurements and is one of the most precise so far in this energy range.

  17. Status of the technologies for the production of the Cherenkov Telescope Array (CTA) mirrors

    CERN Document Server

    Pareschi, G; Baba, H; Bähr, J; Bonardi, A; Bonnoli, G; Brun, P; Canestrari, R; Chadwick, P; Chikawa, M; Carton, P -H; de Souza, V; Dipold, J; Doro, M; Durand, D; Dyrda, M; Förster, A; Garczarczyk, M; Giro, E; Glicenstein, J -F; Hanabata, Y; Hayashida, M; Hrabovski, M; Jeanney, C; Kagaya, M; Katagiri, H; Lessio, L; Mandat, D; Mariotti, M; Medina, C; Michałowski, J; Micolon, P; Nakajima, D; Niemiec, J; Nozato, A; Palatka, M; Pech, M; Peyaud, B; Pühlhofer, G; Rataj, M; Rodeghiero, G; Rojas, G; Rousselle, J; Sakonaka, R; Schovanek, P; Seweryn, K; Schultz, C; Shu, S; Stinzing, F; Stodulski, M; Teshima, M; Travniczek, P; van Eldik, C; Vassiliev, V; Wiśniewski, Ł; Wörnlein, A; Yoshida, T

    2013-01-01

    The Cherenkov Telescope Array (CTA) is the next generation very high-energy gamma-ray observatory, with at least 10 times higher sensitivity than current instruments. CTA will comprise several tens of Imaging Atmospheric Cherenkov Telescopes (IACTs) operated in array-mode and divided into three size classes: large, medium and small telescopes. The total reflective surface could be up to 10,000 m2 requiring unprecedented technological efforts. The properties of the reflector directly influence the telescope performance and thus constitute a fundamental ingredient to improve and maintain the sensitivity. The R&D status of lightweight, reliable and cost-effective mirror facets for the CTA telescope reflectors for the different classes of telescopes is reviewed in this paper.

  18. Design and Operation of FACT -- The First G-APD Cherenkov Telescope

    CERN Document Server

    Anderhub, H; Biland, A; Boccone, V; Braun, I; Bretz, T; Buß, J; Cadoux, F; Commichau, V; Djambazov, L; Dorner, D; Einecke, S; Eisenacher, D; Gendotti, A; Grimm, O; von Gunten, H; Haller, C; Hildebrand, D; Horisberger, U; Huber, B; Kim, K -S; Knoetig, M L; K"ohne, J H; Kr"ahenb"uhl, T; Krumm, B; Lee, M; Lorenz, E; Lustermann, W; Lyard, E; Mannheim, K; Meharga, M; Meier, K; Montaruli, T; Neise, D; Nessi-Tedaldi, F; Overkemping, A -K; Paravac, A; Pauss, F; Renker, D; Rhode, W; Ribordy, M; R"oser, U; Stucki, J -P; Schneider, J; Steinbring, T; Temme, F; Thaele, J; Tobler, S; Viertel, G; Vogler, P; Walter, R; Warda, K; Weitzel, Q; Z"anglein, M

    2013-01-01

    The First G-APD Cherenkov Telescope (FACT) is designed to detect cosmic gamma-rays with energies from several hundred GeV up to about 10 TeV using the Imaging Atmospheric Cherenkov Technique. In contrast to former or existing telescopes, the camera of the FACT telescope is comprised of solid-state Geiger-mode Avalanche Photodiodes (G-APD) instead of photomultiplier tubes for photo detection. It is the first full-scale device of its kind employing this new technology. The telescope is operated at the Observatorio del Roque de los Muchachos (La Palma, Canary Islands, Spain) since fall 2011. This paper describes in detail the design, construction and operation of the system, including hardware and software aspects. Technical experiences gained after one year of operation are discussed and conclusions with regard to future projects are drawn.

  19. Monte Carlo Performance Studies of Candidate Sites for the Cherenkov Telescope Array

    CERN Document Server

    Maier, G; Bernlöhr, K; Bregeon, J; Di Pierro, F; Hassan, T; Jogler, T; Hinton, J; Moralejo, A; Wood, M

    2015-01-01

    The Cherenkov Telescope Array (CTA) is the next-generation gamma-ray observatory with sensitivity in the energy range from 20 GeV to beyond 300 TeV. CTA is proposed to consist of two arrays of 40-100 imaging atmospheric Cherenkov telescopes, with one site located in each of the Northern and Southern Hemispheres. The evaluation process for the candidate sites for CTA is supported by detailed Monte Carlo simulations, which take different attributes like site altitude and geomagnetic field configuration into account. In this contribution we present the comparison of the sensitivity and performance of the different CTA site candidates for the measurement of very-high energy gamma rays.

  20. On the Use of Cherenkov Telescopes for Outer Solar System Body Occultations

    CERN Document Server

    Lacki, Brian C

    2014-01-01

    Imaging Atmosphere Cherenkov Telescopes (IACT) are arrays of very large optical telescopes that are well-suited for rapid photometry of bright sources. I investigate their potential in observing stellar occultations by small objects in the outer Solar System, Transjovian Objects (TJOs). These occultations cast diffraction patterns on the Earth. Current IACT arrays are capable of detecting objects smaller than 100 meters in radius in the Kuiper Belt and 1 km radius out to 5000 AU. The future Cherenkov Telescope Array (CTA) will have even greater capabilities. Because the arrays include several telescopes, they can potentially measure the speeds of TJOs without degeneracies, and the sizes of the TJOs and background stars. I estimate the achievable precision using a Fisher matrix analysis. With CTA, the precisions of these parameter estimations will be as good as a few percent. I consider how often IACTs can observe occultations by members of different TJO populations, including Centaurs, Kuiper Belt Objects (KB...

  1. Sensitivity of the space-based CHerenkov from Astrophysical Neutrinos Telescope (CHANT)

    CERN Document Server

    Neronov, A; Anchordoqui, L A; Adams, J; Olinto, A V

    2016-01-01

    Neutrinos with energies in the PeV to EeV range produce upgoing extensive air showers when they interact underground close enough to the surface of the Earth. We study the possibility for detection of such showers with a system of very wide field-of-view imaging atmospheric Cherenkov telescopes, named CHANT for CHerenkov from Astrophysical Neutrinos Telescope, pointing down to a strip below the Earth's horizon from space. We find that CHANT provides sufficient sensitivity for the study of the astrophysical neutrino flux in a wide energy range, from 10~PeV to 10~EeV. A space-based CHANT system can discover and study in detail the cosmogenic neutrino flux originating from interactions of ultra-high-energy cosmic rays in the intergalactic medium.

  2. A versatile digital camera trigger for telescopes in the Cherenkov Telescope Array

    CERN Document Server

    Schwanke, U; Sulanke, K -H; Vorobiov, S; Wischnewski, R

    2015-01-01

    This paper describes the concept of an FPGA-based digital camera trigger for imaging atmospheric Cherenkov telescopes, developed for the future Cherenkov Telescope Array (CTA). The proposed camera trigger is designed to select images initiated by the Cherenkov emission of extended air showers from very-high energy (VHE, E>20 GeV) photons and charged particles while suppressing signatures from background light. The trigger comprises three stages. A first stage employs programmable discriminators to digitize the signals arriving from the camera channels (pixels). At the second stage, a grid of low-cost FPGAs is used to process the digitized signals for camera regions with 37 pixels. At the third stage, trigger conditions found independently in any of the overlapping 37-pixel regions are combined into a global camera trigger by few central FPGAs. Trigger prototype boards based on Xilinx FPGAs have been designed, built and tested and were shown to function properly. Using these components a full camera trigger wi...

  3. Active gated imaging for automotive safety applications

    Science.gov (United States)

    Grauer, Yoav; Sonn, Ezri

    2015-03-01

    The paper presents the Active Gated Imaging System (AGIS), in relation to the automotive field. AGIS is based on a fast gated-camera equipped with a unique Gated-CMOS sensor, and a pulsed Illuminator, synchronized in the time domain to record images of a certain range of interest which are then processed by computer vision real-time algorithms. In recent years we have learned the system parameters which are most beneficial to night-time driving in terms of; field of view, illumination profile, resolution and processing power. AGIS provides also day-time imaging with additional capabilities, which enhances computer vision safety applications. AGIS provides an excellent candidate for camera-based Advanced Driver Assistance Systems (ADAS) and the path for autonomous driving, in the future, based on its outstanding low/high light-level, harsh weather conditions capabilities and 3D potential growth capabilities.

  4. Biomedical Applications of Terahertz Spectroscopy and Imaging.

    Science.gov (United States)

    Yang, Xiang; Zhao, Xiang; Yang, Ke; Liu, Yueping; Liu, Yu; Fu, Weiling; Luo, Yang

    2016-10-01

    Terahertz (THz=10(12)Hz) radiation has attracted wide attention for its unprecedented sensing ability and its noninvasive and nonionizing properties. Tremendous strides in THz instrumentation have prompted impressive breakthroughs in THz biomedical research. Here, we review the current state of THz spectroscopy and imaging in various biomedical applications ranging from biomolecules, including DNA/RNA, amino acids/peptides, proteins, and carbohydrates, to cells and tissues. We also address the potential biological effects of THz radiation during its biological applications and propose future prospects for this cutting-edge technology.

  5. Terahertz integrated antenna arrays for imaging applications

    OpenAIRE

    Alonso del Pino, María

    2013-01-01

    Terahertz is the portion of the spectrum that covers a frequency range between 300 GHz - 3 THz. This frequency band has proven its potential for imaging applications thanks to the good compromise between spatial resolution and penetration; however, this push towards high frequencies contains many technological difficulties in all the subsystems involved in the signal generation, transmission and detection. The power budget restrictions and high losses that sources and receivers currently suff...

  6. Whole body MR imaging: applications in oncology.

    Science.gov (United States)

    Johnston, C; Brennan, S; Ford, S; Eustace, S

    2006-04-01

    This article reviews technique and clinical applications of whole body MR imaging as a diagnostic tool in cancer staging. In particular the article reviews its role as an alternative to scintigraphy (bone scan and PET) in staging skeletal spread of disease, its role in assessing total tumour burden, its role in multiple myeloma and finally its evolving non oncologic role predominantly assessing total body composition.

  7. Parallelism and Scalability in an Image Processing Application

    DEFF Research Database (Denmark)

    Rasmussen, Morten Sleth; Stuart, Matthias Bo; Karlsson, Sven

    2008-01-01

    parallel programs. This paper investigates parallelism and scalability of an embedded image processing application. The major challenges faced when parallelizing the application were to extract enough parallelism from the application and to reduce load imbalance. The application has limited immediately...

  8. A microwave inverse Cherenkov accelerator (MICA)

    Science.gov (United States)

    Zhang, T. B.; Marshall, T. C.

    1996-02-01

    By "inverting" the stimulated Cherenkov effect to stimulated Cherenkov absorption, it is possible to build an electron accelerator device driven by high power microwaves that propagate in a slow-wave TM mode (axial E-field). In this paper, we have solved for the wave dispersion in the structure, found the field distributions, and then used the Lorentz force equations to obtain the motion of a group of electrons distributed in radius and velocity. We find the radial forces are focusing. Electrons in a well-defined filament ( r < 0.5 mm) remain collimated and do not strike the dielectric. By using the 15 MW of rf power available at 2.865 GHz, we can accelerate an electron beam (˜6 MeV, few ps pulses) to energy ˜16 MeV. This results in a relatively compact structure that has the advantage of a smooth-bore design and no need of magnetic focusing. The techniques for improving the dielectric breakdown the surface should permit axial fields in the range of 100-200 kV/cm.

  9. The high-altitude water Cherenkov Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Mostafa, Miguel A., E-mail: miguel@psu.edu [Department of Physics, Colorado State University, Ft Collins, CO (United States)

    2014-07-01

    The High-Altitude Water Cherenkov (HAWC) observatory is a large field of view, continuously operated, TeV γ -ray experiment under construction at 4,100ma.s.l. in Mexico. The HAWC observatory will have an order of magnitude better sensitivity, angular resolution, and background rejection than its predecessor, the Milagro experiment. The improved performance will allow to detect both the transient and steady emissions, to study the Galactic diffuse emission at TeV energies, and to measure or constrain the TeV spectra of GeV γ -ray sources. In addition, HAWC will be the only ground-based instrument capable of detecting prompt emission from γ -ray bursts above 50 GeV. The HAWC observatory will consist of an array of 300 water Cherenkov detectors (WCDs), each with four photomultiplier tubes. This array is currently under construction on the flanks of the Sierra Negra volcano near the city of Puebla, Mexico. The first 30 WCDs (forming an array approximately the size of Milagro) were deployed in Summer 2012, and 100 WCDs will be taking data by May, 2013. We present in this paper the motivation for constructing the HAWC observatory, the status of the deployment, and the first results from the constantly growing array. (author)

  10. Roughness tolerances for Cherenkov telescope mirrors

    CERN Document Server

    Tayabaly, K; Canestrari, R; Bonnoli, G; Lavagna, M; Pareschi, G

    2016-01-01

    The Cherenkov Telescope Array (CTA) is a forthcoming international ground-based observatory for very high-energy gamma rays. Its goal is to reach sensitivity five to ten times better than existing Cherenkov telescopes such as VERITAS, H.E.S.S. or MAGIC and extend the range of observation to energies down to few tens of GeV and beyond 100 TeV. To achieve this goal, an array of about 100 telescopes is required, meaning a total reflective surface of several thousands of square meters. Thence, the optimal technology used for CTA mirrors manufacture should be both low-cost (~1000 euros/m2) and allow high optical performances over the 300-550 nm wavelength range. More exactly, a reflectivity higher than 85% and a PSF (Point Spread Function) diameter smaller than 1 mrad. Surface roughness can significantly contribute to PSF broadening and limit telescope performances. Fortunately, manufacturing techniques for mirrors are now available to keep the optical scattering well below the geometrically-predictable effect of ...

  11. The High Altitude Water Cherenkov Observatory

    CERN Document Server

    ,

    2013-01-01

    The High Altitude Water Cherenkov (HAWC) observatory is a large field of view, continuously operated, TeV gamma-ray experiment under construction at 4,100 m a.s.l. in Mexico. The HAWC observatory will have an order of magnitude better sensitivity, angular resolution, and background rejection than its predecessor, the Milagro experiment. The improved performance will allow us to detect both transient and steady emissions, to study the Galactic diffuse emission at TeV energies, and to measure or constrain the TeV spectra of GeV gamma-ray sources. In addition, HAWC will be the only ground-based instrument capable of detecting prompt emission from gamma-ray bursts above 50 GeV. The HAWC observatory will consist of an array of 300 water Cherenkov detectors (WCDs), each with four photomultiplier tubes. This array is currently under construction on the flanks of the Sierra Negra volcano near the city of Puebla, Mexico. The first thirty WCDs (forming an array approximately the size of Milagro) were deployed in Summer...

  12. Medical diagnostic imaging systems: technology and applications

    International Nuclear Information System (INIS)

    This book attempts to assess the current status and future developments of the medical imaging industry. The first chapter contains brief descriptions, of the basic principles of various imaging modalities (radiologic, CT, nuclear, ultrasound, and thermography), and a chapter describing areas of clinical applications for each modality follows. Chapter 3 provides a profile of the industry, listing the various manufacturers of medical imaging products and their share of the market, based on 1976 to 1978 statistics. Chapter 4 describes briefly the current sources of research support (industry versus government agencies) but does not provide data either in absolute dollars or relative amounts. Chapters 5 to 14 cover a broad spectrum of advanced imaging systems by categories, including x-ray (5 and 6), CT (7 and 8), nuclear (9 and 10), ultrasound (11), thermography (12), NMR (13), and miscellaneous (14), and they may be considered the meat of the book because they provide the basis for predictions of future developments in the medical imaging industry

  13. The Physics and Nuclear Nonproliferation Goals of WATCHMAN: A WAter CHerenkov Monitor for ANtineutrinos

    CERN Document Server

    Askins, M; Bernstein, A; Dazeley, S; Dye, S T; Handler, T; Hatzikoutelis, A; Hellfeld, D; Jaffke, P; Kamyshkov, Y; Land, B J; Learned, J G; Marleau, P; Mauger, C; Gann, G D Orebi; Roecker, C; Rountree, S D; Shokair, T M; Smy, M B; Svoboda, R; Sweany, M; Vagins, M R; van Bibber, K A; Vogelaar, R B; Wetstein, M J; Yeh, M

    2015-01-01

    This article describes the physics and nonproliferation goals of WATCHMAN, the WAter Cherenkov Monitor for ANtineutrinos. The baseline WATCHMAN design is a kiloton scale gadolinium-doped (Gd) light water Cherenkov detector, placed 13 kilometers from a civil nuclear reactor in the United States. In its first deployment phase, WATCHMAN will be used to remotely detect a change in the operational status of the reactor, providing a first- ever demonstration of the potential of large Gd-doped water detectors for remote reactor monitoring for future international nuclear nonproliferation applications. During its first phase, the detector will provide a critical large-scale test of the ability to tag neutrons and thus distinguish low energy electron neutrinos and antineutrinos. This would make WATCHMAN the only detector capable of providing both direction and flavor identification of supernova neutrinos. It would also be the third largest supernova detector, and the largest underground in the western hemisphere. In a...

  14. Image Understanding Applications of Lattice Autoassociative Memories.

    Science.gov (United States)

    Grana, Manuel; Chyzhyk, Darya

    2016-09-01

    Multivariate mathematical morphology (MMM) aims to extend the mathematical morphology from gray scale images to images whose pixels are high-dimensional vectors, such as remote sensing hyperspectral images and functional magnetic resonance images (fMRIs). Defining an ordering over the multidimensional image data space is a fundamental issue MMM, to ensure that ensuing morphological operators and filters are mathematically consistent. Recent approaches use the outputs of two-class classifiers to build such reduced orderings. This paper presents the applications of MMM built on reduced supervised orderings based on lattice autoassociative memories (LAAMs) recall error measured by the Chebyshev distance. Foreground supervised orderings use one set of training data from a foreground class, whereas background/foreground supervised orderings use two training data sets, one for each relevant class. The first case study refers to the realization of the thematic segmentation of the hyperspectral images using spatial-spectral information. Spectral classification is enhanced by a spatial processing consisting in the spatial correction guided by a watershed segmentation computed by the LAAM-based morphological operators. The approach improves the state-of-the-art hyperspectral spatial-spectral thematic map building approaches. The second case study is the analysis of resting state fMRI data, working on a data set of healthy controls, schizophrenia patients with and without auditory hallucinations. We perform two experiments: 1) the localization of differences in brain functional networks on population-dependent templates and 2) the classification of subjects into each possible pair of cases. In this data set, we find that the LAAM-based morphological features improve over the conventional correlation-based graph measure features often employed in fMRI data classification.

  15. Atmospheric multiple scattering of fluorescence and Cherenkov light emitted by extensive air showers

    CERN Document Server

    Pekala, J; Wilczynska, B; Wilczynski, H; 10.1016/j.nima.2009.03.244

    2009-01-01

    Atmospheric scattering of light emitted by an air shower not only attenuates direct fluorescence light from the shower, but also contributes to the observed shower light. So far only direct and singly-scattered Cherenkov photons have been taken into account in routine analyses of the observed optical image of air showers. In this paper a Monte Carlo method of evaluating the contribution of multiply scattered light to the optical air shower image is presented, as well as results of simulations and a parameterization of scattered light contribution to measured shower signal.

  16. Applications of scientific imaging in environmental toxicology

    Science.gov (United States)

    El-Demerdash, Aref M.

    The national goals of clean air, clean water, and healthy ecosystems are a few of the primary forces that drive the need for better environmental monitoring. As we approach the end of the 1990s, the environmental questions at regional to global scales are being redefined and refined in the light of developments in environmental understanding and technological capability. Research in the use of scientific imaging data for the study of the environment is urgently needed in order to explore the possibilities of utilizing emerging new technologies. The objective of this research proposal is to demonstrate the usability of a wealth of new technology made available in the last decade to providing a better understanding of environmental problems. Research is focused in two imaging techniques macro and micro imaging. Several examples of applications of scientific imaging in research in the field of environmental toxicology were presented. This was achieved on two scales, micro and macro imaging. On the micro level four specific examples were covered. First, the effect of utilizing scanning electron microscopy as an imaging tool in enhancing taxa identification when studying diatoms was presented. Second, scanning electron microscopy combined with energy dispersive x-ray analyzer were demonstrated as a valuable and effective tool for identifying and analyzing household dust samples. Third, electronic autoradiography combined with FT-IR microscopy were used to study the distribution pattern of [14C]-Malathion in rats as a result of dermal exposure. The results of the autoradiography made on skin sections of the application site revealed the presence of [ 14C]-activity in the first region of the skin. These results were evidenced by FT-IR microscopy. The obtained results suggest that the penetration of Malathion into the skin and other tissues is vehicle and dose dependent. The results also suggest the use of FT-IR microscopy imaging for monitoring the disposition of

  17. Cherenkov light-based beam profiling for ultrarelativistic electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Adli, E., E-mail: Erik.Adli@fys.uio.no [Department of Physics, University of Oslo, N-0316 Oslo (Norway); SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Gessner, S.J.; Corde, S.; Hogan, M.J. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Bjerke, H.H. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Department of Physics, Norwegian University of Science and Technology, N-7491 Trondheim (Norway)

    2015-05-21

    We describe a beam profile monitor design based on Cherenkov light emitted from a charged particle beam in an air gap. The main components of the profile monitor are silicon wafers used to reflect Cherenkov light onto a camera lens system. The design allows for measuring large beam sizes, with large photon yield per beam charge and excellent signal linearity with beam charge. The profile monitor signal is independent of the particle energy for ultrarelativistic particles. Different design and parameter considerations are discussed. A Cherenkov light-based profile monitor has been installed at the FACET User Facility at SLAC. We report on the measured performance of this profile monitor.

  18. Cherenkov neutron detector for fusion reaction and runaway electron diagnostics

    International Nuclear Information System (INIS)

    A Cherenkov-type neutron detector was newly developed and neutron measurement experiments were performed at Korea Superconducting Tokamak Advanced Research. It was shown that the Cherenkov neutron detector can monitor the time-resolved neutron flux from deuterium-fueled fusion plasmas. Owing to the high temporal resolution of the detector, fast behaviors of runaway electrons, such as the neutron spikes, could be observed clearly. It is expected that the Cherenkov neutron detector could be utilized to provide useful information on runaway electrons as well as fusion reaction rate in fusion plasmas

  19. Tachyonic Cherenkov emission from Jupiter's radio electrons

    Energy Technology Data Exchange (ETDEWEB)

    Tomaschitz, Roman, E-mail: tom@geminga.org

    2013-12-17

    Tachyonic Cherenkov radiation from inertial relativistic electrons in the Jovian radiation belts is studied. The tachyonic modes are coupled to a frequency-dependent permeability tensor and admit a negative mass-square, rendering them superluminal and dispersive. The superluminal radiation field can be cast into Maxwellian form, using 3D field strengths and inductions, and the spectral densities of tachyonic Cherenkov radiation are derived. The negative mass-square gives rise to a longitudinal flux component. A spectral fit to Jupiter's radio spectrum, inferred from ground-based observations and the Cassini 2001 fly-by, is performed with tachyonic Cherenkov flux densities averaged over a thermal electron population.

  20. The Cherenkov Radiation for Non-Trivial Systems

    International Nuclear Information System (INIS)

    The charge pathways and the dielectric properties of the medium are two essential aspects to be considered in the study of the emission of Cherenkov radiation. We described the evolution of the Cherenkov wavefront when the charges follow circular or helical pathways. Also we derive expressions for the refractive Index in different transparent media (solid, liquid or gas), focusing our attention on optically active plasmas. The optical analogies between the plasma and the birefringent crystals is studied in detail. Finally, we list some examples of plasmas, which can be considered emitters of Cherenkov radiation. (Author) 52 refs

  1. Calibration of the Cherenkov Telescope Array

    CERN Document Server

    Gaug, Markus; Berge, David; Reyes, Raquel de los; Doro, Michele; Foerster, Andreas; Maccarone, Maria Concetta; Parsons, Dan; van Eldik, Christopher

    2015-01-01

    The construction of the Cherenkov Telescope Array is expected to start soon. We will present the baseline methods and their extensions currently foreseen to calibrate the observatory. These are bound to achieve the strong requirements on allowed systematic uncertainties for the reconstructed gamma-ray energy and flux scales, as well as on the pointing resolution, and on the overall duty cycle of the observatory. Onsite calibration activities are designed to include a robust and efficient calibration of the telescope cameras, and various methods and instruments to achieve calibration of the overall optical throughput of each telescope, leading to both inter-telescope calibration and an absolute calibration of the entire observatory. One important aspect of the onsite calibration is a correct understanding of the atmosphere above the telescopes, which constitutes the calorimeter of this detection technique. It is planned to be constantly monitored with state-of-the-art instruments to obtain a full molecular and...

  2. Observer Access to the Cherenkov Telescope Array

    CERN Document Server

    Knödlseder, Jürgen; Boisson, Catherine; Brau-Nogué, Sylvie; Deil, Christoph; Khélifi, Bruno; Mayer, Michael; Walter, Roland

    2015-01-01

    The Cherenkov Telescope Array (CTA), a ground-based facility for very-high-energy (VHE) gamma-ray astronomy, will operate as an open observatory, serving a wide scientific community to explore and to study the non-thermal universe. Open community access is a novelty in this domain, putting a challenge on the implementation of services that make VHE gamma-ray astronomy as accessible as any other waveband. We present here the design of the CTA Observer Access system that comprises support of scientific users, dissemination of data and software, tools for scientific analysis, and the system to submit observing proposals. We outline the scientific user workflows and provide the status of the current developments.

  3. Application of Java technology in radiation image processing

    International Nuclear Information System (INIS)

    The acquisition and processing of radiation image plays an important role in modern application of civil nuclear technology. The author analyzes the rationale of Java image processing technology which includes Java AWT, Java 2D and JAI. In order to demonstrate applicability of Java technology in field of image processing, examples of application of JAI technology in processing of radiation images of large container have been given

  4. Constraint on ghost-free bigravity from gravitational Cherenkov radiation

    Science.gov (United States)

    Kimura, Rampei; Tanaka, Takahiro; Yamamoto, Kazuhiro; Yamashita, Yasuho

    2016-09-01

    We investigate gravitational Cherenkov radiation in a healthy branch of background solutions in the ghost-free bigravity model. In this model, because of the modification of dispersion relations, each polarization mode can possess subluminal phase velocities, and the gravitational Cherenkov radiation could be potentially emitted from a relativistic particle. In the present paper, we derive conditions for the process of the gravitational Cherenkov radiation to occur and estimate the energy emission rate for each polarization mode. We found that the gravitational Cherenkov radiation emitted even from an ultrahigh energy cosmic ray is sufficiently suppressed for the graviton's effective mass less than 100 eV, and the bigravity model with dark matter coupled to the hidden metric is therefore consistent with observations of high energy cosmic rays.

  5. Constraint on ghost-free bigravity from gravitational Cherenkov radiation

    CERN Document Server

    Kimura, Rampei; Yamamoto, Kazuhiro; Yamashita, Yasuho

    2016-01-01

    We investigate gravitational Cherenkov radiation in a healthy branch of background solutions in the ghost-free bigravity model. In this model, because of the modification of dispersion relations, each polarization mode can possess subluminal phase velocities, and the gravitational Cherenkov radiation could be potentially emitted from a relativistic particle. In the present paper, we derive conditions for the process of the gravitational Cherenkov radiation to occur and estimate the energy emission rate for each polarization mode. We found that the gravitational Cherenkov radiation emitted even from an ultrahigh energy cosmic ray is sufficiently suppressed for the graviton's effective mass less than $100\\,{\\rm eV}$, and the bigravity model with dark matter coupled to the hidden metric is therefore consistent with observations of high energy cosmic rays.

  6. X-ray diffraction radiation in conditions of Cherenkov effect

    NARCIS (Netherlands)

    Tishchenko, A. A.; Potylitsyn, A. P.; Strikhanov, M. N.

    2006-01-01

    X-ray diffraction radiation from ultra-relativistic electrons moving near an absorbing target is considered. The emission yield is found to increase significantly in conditions of Cherenkov effect. (c) 2006 Elsevier B.V. All rights reserved.

  7. Fast timing and trigger Cherenkov detector for collider experiments

    OpenAIRE

    Grigoryev, V. A.; Kaplin, V. A.; Karavicheva, T.L.; Konevskikh, A. S.; Kurepin, A. B.; Loginov, V. A.; Melikyan, A.; Morozov, I. V.; Reshetin, A. I.; Serebryakov, D. V.; Shabanov, A. I.; Slupecki, Maciej; Trzaska, Wladyslaw; Tykmanov, E. M.

    2016-01-01

    Analysis of fast timing and trigger Cherenkov detector’s design for its use in collider experiments is presented. Several specific requirements are taken into account – necessity of the radiator’s placement as close to the beam pipe as possible along with the requirement of gapless (solid) radiator’s design. Characteristics of the Cherenkov detector’s laboratory prototype obtained using a pion beam at the CERN Proton Synchrotron are also presented, showing the possibility of ob...

  8. Application of PET/SPECT imaging in vascular disease

    NARCIS (Netherlands)

    van der Vaart, M. G.; Meerwaidt, R.; Slart, R. H. J. A.; van Dam, G. M.; Tio, R. A.; Zeebregts, C. J.

    2008-01-01

    Background. Nuclear medicine imaging differs from other imaging modalities by showing physiological processes instead of anatomical details. Objective. To describe the current applications of positron emission tomography (PET) and single photon emission computed tomography (SPECT) as a diagnostic to

  9. Inverse synthetic aperture radar imaging principles, algorithms and applications

    CERN Document Server

    Chen , Victor C

    2014-01-01

    Inverse Synthetic Aperture Radar Imaging: Principles, Algorithms and Applications is based on the latest research on ISAR imaging of moving targets and non-cooperative target recognition (NCTR). With a focus on the advances and applications, this book will provide readers with a working knowledge on various algorithms of ISAR imaging of targets and implementation with MATLAB. These MATLAB algorithms will prove useful in order to visualize and manipulate some simulated ISAR images.

  10. Novel Metal Clusters for Imaging Applications

    KAUST Repository

    Alsaiari, Shahad K.

    2014-05-01

    During the past few years, gold nanoparticles (AuNPs) have received considerable attention in many fields due to their optical properties, photothermal effect and biocompatibility. AuNPs, particularly AuNCs and AuNRs, exhibit great potential in diagnostics and imaging. In the present study, AuNCs were used to selectively image and quantify intracellular antioxidants. It was reported by Chen et al. that the strong fluorescence of AuNCs is quenched by highly reactive oxygen species (hROS). Most of applications depend on fluorescence quenching, however, for our project we designed turn-on fluorescent sensors using AuNCs that sense antioxidants. In the presence of antioxidants, AuNCs fluorescence switch on, while in the absence of antioxidants their fluorescence immediately turn off due to hROS effect. AuNRs were also used for cellular imaging in which AuNRs were conjugated to Cy3-labelled molecular beacon (MB) DNA. Next, the previous complex was loaded in two different strains of magnetotactic bacteria (MTB). MTB were used as a targeted delivery vehicle in which magnetosomes direct the movement of bacteria. The DNA sequence was specific to a certain sequence in mitochondria. The exposure of MTB to an alternating magnetic field (AMF) leads to the increase of temperature inside the bacteria, which destruct the cell wall, and hence, bacterial payload is released. When MD-DNA hybrid with the target sequence, AuNR and Cy3 separate from each other, the fluorescence of the Cy3 is restored.

  11. Wavelet Technique Applications in Planetary Nebulae Images

    Science.gov (United States)

    Leal Ferreira, M. L.; Rabaça, C. R.; Cuisinier, F.; Epitácio Pereira, D. N.

    2009-05-01

    Through the application of the wavelet technique to a planetary nebulae image, we are able to identify different scale sizes structures present in its wavelet coefficient decompositions. In a multiscale vision model, an object is defined as a hierarchical set of these structures. We can then use this model to independently reconstruct the different objects that compose the nebulae. The result is the separation and identification of superposed objects, some of them with very low surface brightness, what makes them, in general, very difficult to be seen in the original images due to the presence of noise. This allows us to make a more detailed analysis of brightness distribution in these sources. In this project, we use this method to perform a detailed morphological study of some planetary nebulae and to investigate whether one of them indeed shows internal temperature fluctuations. We have also conducted a series of tests concerning the reliability of the method and the confidence level of the objects detected. The wavelet code used in this project is called OV_WAV and was developed by the UFRJ's Astronomy Departament team.

  12. On the optical readout of gas avalanche chambers and its applications

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, M.; Breskin, A.; Charpak, G.; Daubie, E.; Dominik, W.; Fabre, J.P.; Gaudean, J.; Sauli, F.; Sauvage, D.; Strock, P.; Zeludziewicz, T.

    1986-09-25

    Gaseous avalanche counters with mixtures containing the vapour of triethylamine, are coupled to an optical readout system. Different configurations are studied in order to visualize ionization tracks produced by high-energy particles or images caused by vacuum ultraviolet light. This instrument has potential applications in the study of rare or complex events - such as the search for double-beta and proton decay - or in Cherenkov ring imaging.

  13. On the optical readout of gas avalanche chambers and its applications

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, M.; Charpak, G.; Fabre, J.P.; Gaudean, J.; Sauli, F.; Sauvage, D.; Strock, P.; Zeludziewicz, T.; Breskin, A.; Daubie, E.

    1988-01-01

    Gaseous avalanche counters with mixtures containing the vapour of triethylamine, are coupled to an optical readout system. Different configurations are studied in order to visualize ionization tracks produced by high-energy particles or images caused by vacuum ultraviolet light. This instrument has potential applications in the study of rare or complex events - such as the search for double-beta and proton decay - or in Cherenkov ring imaging.

  14. Second Harmonic Generation Imaging Microscopy: Applications to Diseases Diagnostics

    OpenAIRE

    Campagnola, Paul

    2011-01-01

    Second Harmonic Generation microscopy has emerged as a powerful new optical imaging modality. This Feature describes its chemical and physical principles and highlights current applications in disease diagnostics.

  15. Cherenkov radiation with massive, C P T -violating photons

    Science.gov (United States)

    Colladay, Don; McDonald, Patrick; Potting, Robertus

    2016-06-01

    The source of C P T violation in the photon sector of the Standard Model Extension arises from a Chern-Simons-like contribution that involves a coupling to a fixed background vector field kAF μ . These Lorentz- and C P T -violating photons have well-known theoretical issues that arise from missing states at low momenta when kAF μ is timelike. In order to make the theory consistent, a tiny mass for the photon can be introduced, well below current experimental bounds. The implementation of canonical quantization can then be implemented as in the C P T -preserving case by using the Stückelberg mechanism. We explicitly construct a covariant basis of properly normalized polarization vectors at fixed three-momentum satisfying the momentum space field equations, in terms of which the vector field can be expanded. As an application of the theory, we calculate the Cherenkov radiation rate for the case of purely timelike kAF μ and find a radiation rate at high energies that has a contribution that does not depend on the mass used to regulate the photons.

  16. Cherenkov Radiation with Massive, CPT-violating Photons

    CERN Document Server

    Colladay, Don; Potting, Robertus

    2016-01-01

    The source of CPT-violation in the photon sector of the Standard Model Extension arises from a Chern-Simons-like contribution that involves a coupling to a fixed background vector field $k_{AF}^\\mu$. These Lorentz- and CPT-violating photons have well-known theoretical issues that arise from missing states at low momenta when $k_{AF}^\\mu$ is timelike. In order to make the theory consistent, a tiny mass for the photon can be introduced, well below current experimental bounds. The implementation of canonical quantization can then be implemented as in the CPT-preserving case by using the St\\"uckelberg mechanism. We explicitly construct a covariant basis of properly-normalized polarization vectors at fixed three-momentum satisfying the momentum space field equations, in terms of which the vector field can be expanded. As an application of the theory, we calculate the Cherenkov radiation rate for the case of purely timelike $k_{AF}^\\mu$, and find a radiation rate at high energies that has a contribution that does n...

  17. Kalman filter tracking in a Cherenkov neutrino telescope

    International Nuclear Information System (INIS)

    The reconstruction of tracks in underwater Cherenkov neutrino telescopes is strongly complicated due to large background counting rate originates from 40K beta decay and to the electromagnetic showers accompanying high energy muons together with the effects of light propagation in the water, in particular the photon scattering. These two effects lead to a non-linear problem with a non-Gaussian measurement noise. A method for track reconstruction based on Kalman filter approach in this situation is presented. We use Gaussian Sum Filter algorithm to take into account non-Gaussian process noise. While usual Kalman filter estimators based on linear least-square method are optimal in case all observations are Gaussian distributed, the Gaussian Sum Filter offers a better treatment of non-Gaussian process noise and/or measurement errors when these are modeled by Gaussian mixtures. As an example of the application, the results of muon track reconstruction in NEMO underwater neutrino telescope are presented as well as the comparison of its capability with other standard track reconstruction methods.

  18. TH-C-17A-04: Shining Light On the Implementation of Cherenkov Emission in Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Zlateva, Y; Quitoriano, N [I El Naqa, McGill University, Montreal, QC (Canada)

    2014-06-15

    Purpose: We hypothesize that Cherenkov emission (CE) by radiotherapy beams is correlated with radiation dose, CE detection can be maximized by a spectral shift towards the near-infrared (NIR) window of biological tissue, and in certain tissue types (ex. breast/oropharynx), it could prove superior to mega-voltage (MV) imaging. Therefore, we compare CE imaging to onboard MV imaging. Methods: Dose-CE correlation was investigated via simulation and experiment. A Monte Carlo (MC) CE simulator was designed using Geant4. Experimental phantoms include: water; tissuesimulating phantom composed of water, fat emulsion, and beef blood; plastic phantom with solid water insert. The optical spectrometry system consisted of a multi-mode optical fiber and diffraction-grating spectrometer incorporating a front/back-illuminated charge-coupled device (CCD). CdSe/ZnS quantum dots (QDs), emitting at (650±10) nm, were used to achieve NIR shift of the CE signal. CE and MV images were acquired with a complementary metal-oxide-semiconductor (CMOS) camera and an electronic portal imaging device (EPID), respectively. Results: MC and experimental studies indicate a strong linear correlation between radiation dose and CE (Pearson coefficient > 0.99). CE by an 18 MeV beam was effectively shifted towards the NIR in water and in a tissue-simulating phantom, exhibiting a 50% increase at 650 nm for QD depths of ∼3 mm. CE images exhibited relative contrast superior to EPID images by a factor of 30. Conclusion: Our work supports the potential for application of CE in radiotherapy online imaging for patient setup and treatment verification, since CE is intrinsic to the beam and non-ionizing, and QDs can be used to improve CE detectability, yielding image quality superior to MV imaging for the case of low density variability, low optical attenuation materials, such as breast or oropharyngeal cavities. Ongoing work involves microenvironment functionalization of QDs and application of multichannel

  19. TH-C-17A-04: Shining Light On the Implementation of Cherenkov Emission in Radiation Therapy

    International Nuclear Information System (INIS)

    Purpose: We hypothesize that Cherenkov emission (CE) by radiotherapy beams is correlated with radiation dose, CE detection can be maximized by a spectral shift towards the near-infrared (NIR) window of biological tissue, and in certain tissue types (ex. breast/oropharynx), it could prove superior to mega-voltage (MV) imaging. Therefore, we compare CE imaging to onboard MV imaging. Methods: Dose-CE correlation was investigated via simulation and experiment. A Monte Carlo (MC) CE simulator was designed using Geant4. Experimental phantoms include: water; tissuesimulating phantom composed of water, fat emulsion, and beef blood; plastic phantom with solid water insert. The optical spectrometry system consisted of a multi-mode optical fiber and diffraction-grating spectrometer incorporating a front/back-illuminated charge-coupled device (CCD). CdSe/ZnS quantum dots (QDs), emitting at (650±10) nm, were used to achieve NIR shift of the CE signal. CE and MV images were acquired with a complementary metal-oxide-semiconductor (CMOS) camera and an electronic portal imaging device (EPID), respectively. Results: MC and experimental studies indicate a strong linear correlation between radiation dose and CE (Pearson coefficient > 0.99). CE by an 18 MeV beam was effectively shifted towards the NIR in water and in a tissue-simulating phantom, exhibiting a 50% increase at 650 nm for QD depths of ∼3 mm. CE images exhibited relative contrast superior to EPID images by a factor of 30. Conclusion: Our work supports the potential for application of CE in radiotherapy online imaging for patient setup and treatment verification, since CE is intrinsic to the beam and non-ionizing, and QDs can be used to improve CE detectability, yielding image quality superior to MV imaging for the case of low density variability, low optical attenuation materials, such as breast or oropharyngeal cavities. Ongoing work involves microenvironment functionalization of QDs and application of multichannel

  20. Sensivity studies for the Cherenkov Telescope Array

    Science.gov (United States)

    Collado, Tarek Hassan

    2015-06-01

    Since the creation of the first telescope in the 17th century, every major discovery in astrophysics has been the direct consequence of the development of novel observation techniques, opening new windows in the electromagnetic spectrum. After Karl Jansky discovered serendipitously the first radio source in 1933, Grote Reber built the first parabolic radio telescope in his backyard, planting the seed of a whole new field in astronomy. Similarly, new technologies in the 1950s allowed the establishment of other fields, such as the infrared, ultraviolet or the X-rays. The highest energy end of the electromagnetic spectrum, the γ-ray range, represents the last unexplored window for astronomers and should reveal the most extreme phenomena that take place in the Universe. Given the technical complexity of γ-ray detection and the extremely relative low fluxes, γ-ray astronomy has undergone a slower development compared to other wavelengths. Nowadays, the great success of consecutive space missions together with the development and refinement of new detection techniques from the ground, has allowed outstanding scientific results and has brought gamma-ray astronomy to a worthy level in par with other astronomy fields. This work is devoted to the study and improvement of the future Cherenkov Telescope Array (CTA), the next generation of ground based γ-ray detectors, designed to observe photons with the highest energies ever observed from cosmic sources.

  1. A backscattered x-ray imager for medical applications

    Science.gov (United States)

    Morris, Eric Jude L.; Dibianca, Frank A.; Shukla, Hemant; Gulabani, Daya

    2005-04-01

    Conventional X-ray radiographic systems rely on transmitted photons for the production of images. Backscatter imaging makes use of the more abundant scattered photons for image formation. Specifically, incoherently (Compton) scattered X-ray photons are detected and used for image formation in this modality of medical imaging. However, additional information is obtained when the transmitted X-ray photons are also detected and used. Transmission radiography produces a two-dimensional image of a three dimensional system, therefore image information from a shallower object is often contaminated by image information from underlying objects. Backscattered x-ray imaging largely overcomes this deficiency by imaging depth selectively, which reduces corruption of shallow imaging information by information from deeper objects lying under it. Backscattered x-ray imaging may be particularly useful for examining anatomical structures at shallow depths beneath the skin. Some typical applications for such imaging might be breast imaging, middle ear imaging, imaging of skin melanomas, etc. Previous investigations, by way of theoretical calculations and computational simulations into the feasibility of this kind of imaging have uncovered high-contrast and SNR parameters. Simulations indicate that this method can be used for imaging relatively high-density objects at depths of up to approximately five centimeters below the surface. This paper presents both theoretical and experimental SNR results on this new medical imaging modality.

  2. A Prototype Data Format for the Cherenkov Telescope Array: Regions Of Interest (ROI)

    CERN Document Server

    ,

    2015-01-01

    The Cherenkov Telescope Array (CTA) is a ground-based $\\gamma$-ray observatory that will observe the full sky in the energy range from 20 GeV to 100 TeV from facilities in both hemispheres. It is proposed to consist of more than 100 telescopes and the large amount of data produced will exceed the volume of current VHE Imaging Atmospheric Cherenkov Telescopes by $\\sim$two orders of magnitude. This volume of data represents a new challenge to the community, which is looking for new data formats to transfer and store the CTA data. One of the prototypes currently under study is the ROI (Regions Of Interest) file format for camera images. It can store only those pixels of a camera image that are close to the shower, thus removing the major part of the night sky background (NSB) while keeping all pixels that might belong to the shower. Simple on-the-fly compression is used to reduce the file size even further. Here, we explain the ROI prototype in detail and present preliminary results when applied to simulations.

  3. Using Raster Scans of Bright Stars to Measure the Relative Total Throughputs of Cherenkov Telescopes

    CERN Document Server

    Griffin, Sean

    2013-01-01

    Gamma-ray astronomy at energies in excess of 100 GeV is carried out using arrays of imaging Cherenkov telescopes. Each telescope comprises a large reflector, of order 10 m diameter, made of many mirror facets, and a camera consisting of a matrix of photomultiplier pixels. Differences in the total throughput between nominally identical telescopes, due to aging of the mirrors and PMTs and other effects, should be monitored to reduce possible systematic errors. One way to directly measure the throughput of such telescopes is to track bright stars and measure the photocurrents produced by their light falling on camera pixels. We have developed such a procedure using the four telescopes in the VERITAS array. We note the technique is general, however, and could be applied to other imaging Cherenkov experiments. For this measurement, a raster scan is performed on a single star such that its image is swept across the central pixels in the camera, thus providing a statistically robust set of measurements in a short pe...

  4. Design of a Cherenkov telescope for the measurement of PCR composition above 1 PeV

    Directory of Open Access Journals (Sweden)

    Galkin V I

    2013-06-01

    Full Text Available The problem of PCR Composition at super high energies is far from being solved.EAS Cherenkov light spatial-angular distribution (CL SAD can yield important information on the primary mass. In order to use EAS CL SAD for the study of PCR composition one needs a set of imaging telescopes with the appropriate parameters supported by a dense net of fast optical detectors capable of measuring EAS Cherenkov light pulses. On the basis of full Monte-Carlo simulations the pixel size of imaging telescopes is optimized for a specific observation level ∼4km which is typical for the Eastern Pamir mountains. Another goal to be pursued by the new detector array is the search for ultra high energy gamma ray sources and this is where the imaging technique can help a lot. A simple criterion is introduced to recognize gamma-quanta against the proton background and its performance, once again analyzed using simulated events, sets certain limits to the pixel size.

  5. Characteristics of Cherenkov Radiation in Naturally Occuring Ice

    CERN Document Server

    Mikkelsen, R E; Uggerhøj, U I; Klein, S R

    2016-01-01

    We revisit the theory of Cherenkov radiation in uniaxial crystals. Historically, a number of flawed attempts have been made at explaining this radiation phenomenon and a consistent error-free description is nowhere available. We apply our calculation to a large modern day telescope - IceCube. Being located at the Antarctica, this detector makes use of the naturally occuring ice as a medium to generate Cherenkov radiation. However, due to the high pressure at the depth of the detector site, large volumes of hexagonal ice crystals are formed. We calculate how this affects the Cherenkov radiation yield and angular dependence. We conclude that the effect is small, at most about a percent, and would only be relevant in future high precision instruments like e.g. Precision IceCube Next Generation Upgrade (PINGU). For radio-Cherenkov experiments which use the presence of a clear Cherenkov cone to determine the arrival direction, any variation in emission angle will directly and linearly translate into a change in ap...

  6. Application of Uncooled Monolithic Thermoelectric Linear Arrays to Imaging Radiometers

    Science.gov (United States)

    Kruse, Paul W.

    Introduction Identification of Incipient Failure of Railcar Wheels Technical Description of the Model IR 1000 Imaging Radiometer Performance of the Model IR 1000 Imaging Radiometer Initial Application Summary Imaging Radiometer for Predictive and Preventive Maintenance Description Operation Specifications Summary References INDEX CONTENTS OF VOLUMES IN THIS SERIES

  7. Practical Applications of Synthetic Aperture Imaging

    DEFF Research Database (Denmark)

    Nikolov, Svetoslav Ivanov; Kortbek, Jacob; Jensen, Jørgen Arendt

    2010-01-01

    Synthetic aperture imaging has been a focus of research for almost 3 decades. The research carried out at the Center for Fast Ultrasound Imaging has demonstrated that synthetic aperture focusing not only can be used in-vivo, but that it also yields superior B-mode and blood flow images. In the last...

  8. Large Size Telescope camera support structures for the Cherenkov Telescope Array

    CERN Document Server

    Deleglise, G; Lamanna, G

    2013-01-01

    The design of the camera support structures for the Cherenkov Telescope Array (CTA) Large Size Telescopes (LSTs) is based on an elliptical arch geometry reinforced along its orthogonal projection by two symmetric sets of stabilizing ropes. The main requirements in terms of minimal camera displacement, minimal weight, minimal shadowing on the telescope mirror, maximal strength of the structures and fast dynamical stabilization have led to the application of Carbon Fibre Plastic Reinforced (CFPR) technologies. This work presents the design, static and dynamic performance of the telescope fulfilling critical specifications for the major scientific objectives of the CTA LST, e.g. Gamma Ray Burst detection.

  9. Robust image modeling technique with a bioluminescence image segmentation application

    Science.gov (United States)

    Zhong, Jianghong; Wang, Ruiping; Tian, Jie

    2009-02-01

    A robust pattern classifier algorithm for the variable symmetric plane model, where the driving noise is a mixture of a Gaussian and an outlier process, is developed. The veracity and high-speed performance of the pattern recognition algorithm is proved. Bioluminescence tomography (BLT) has recently gained wide acceptance in the field of in vivo small animal molecular imaging. So that it is very important for BLT to how to acquire the highprecision region of interest in a bioluminescence image (BLI) in order to decrease loss of the customers because of inaccuracy in quantitative analysis. An algorithm in the mode is developed to improve operation speed, which estimates parameters and original image intensity simultaneously from the noise corrupted image derived from the BLT optical hardware system. The focus pixel value is obtained from the symmetric plane according to a more realistic assumption for the noise sequence in the restored image. The size of neighborhood is adaptive and small. What's more, the classifier function is base on the statistic features. If the qualifications for the classifier are satisfied, the focus pixel intensity is setup as the largest value in the neighborhood.Otherwise, it will be zeros.Finally,pseudo-color is added up to the result of the bioluminescence segmented image. The whole process has been implemented in our 2D BLT optical system platform and the model is proved.

  10. Separation of scintillation and Cherenkov lights in linear alkyl benzene

    Science.gov (United States)

    Li, Mohan; Guo, Ziyi; Yeh, Minfang; Wang, Zhe; Chen, Shaomin

    2016-09-01

    To separate scintillation and Cherenkov lights in water-based liquid scintillator detectors is a desired feature for future neutrino and proton decay experiments. Linear alkyl benzene (LAB) is one important ingredient of a water-based liquid scintillator currently under development. In this paper we report on the separation of scintillation and Cherenkov lights observed in an LAB sample. The rise and decay times of the scintillation light are measured to be (7.7 ± 3.0) ns and (36.6 ± 2.4) ns , respectively, while the full width [-3σ, 3σ] of the Cherenkov light is 12 ns and is dominated by the time resolution of the photomultiplier tubes. The scintillation light yield was measured to be (1.01 ± 0.12) ×103 photons / MeV .

  11. Separation of Scintillation and Cherenkov Lights in Linear Alkyl Benzene

    CERN Document Server

    Li, Mohan; Yeh, Minfang; Wang, Zhe; Chen, Shaomin

    2015-01-01

    To separate scintillation and Cherenkov lights in water-based liquid scintillator detectors is a desired feature for future neutrino and proton decay researches. Linear alkyl benzene (LAB) is one important ingredient of a water-based liquid scintillator being developed. In this paper we observed a good separation of scintillation and Cherenkov lights in an LAB sample. The rising and decay times of the scintillation light of the LAB were measured to be $(7.7\\pm3.0)\\ \\rm{ns}$ and $(36.6\\pm2.4)\\ \\rm{ns}$, respectively, while the full width [-3$\\sigma$, 3$\\sigma$] of the Cherenkov light was 12 ns dominated by the time resolution of our photomultiplier tubes. The light yield of the scintillation was measured to be $(1.01\\pm0.12)\\times10^3\\ \\rm{photons}/\\rm{MeV}$.

  12. The first GCT camera for the Cherenkov Telescope Array

    CERN Document Server

    De Franco, A.; Allan, D.; Armstrong, T.; Ashton, T.; Balzer, A.; Berge, D.; Bose, R.; Brown, A.M.; Buckley, J.; Chadwick, P.M.; Cooke, P.; Cotter, G.; Daniel, M.K.; Funk, S.; Greenshaw, T.; Hinton, J.; Kraus, M.; Lapington, J.; Molyneux, P.; Moore, P.; Nolan, S.; Okumura, A.; Ross, D.; Rulten, C.; Schmoll, J.; Schoorlemmer, H.; Stephan, M.; Sutcliffe, P.; Tajima, H.; Thornhill, J.; Tibaldo, L.; Varner, G.; Watson, J.; Zink, A.

    2015-01-01

    The Gamma Cherenkov Telescope (GCT) is proposed to be part of the Small Size Telescope (SST) array of the Cherenkov Telescope Array (CTA). The GCT dual-mirror optical design allows the use of a compact camera of diameter roughly 0.4 m. The curved focal plane is equipped with 2048 pixels of ~0.2{\\deg} angular size, resulting in a field of view of ~9{\\deg}. The GCT camera is designed to record the flashes of Cherenkov light from electromagnetic cascades, which last only a few tens of nanoseconds. Modules based on custom ASICs provide the required fast electronics, facilitating sampling and digitisation as well as first level of triggering. The first GCT camera prototype is currently being commissioned in the UK. On-telescope tests are planned later this year. Here we give a detailed description of the camera prototype and present recent progress with testing and commissioning.

  13. Research and Development for a Gadolinium Doped Water Cherenkov Detector

    CERN Document Server

    Renshaw, Andrew

    2012-01-01

    The proposed introduction of a soluble gadolinium (Gd) compound into water Cherenkov detectors can result in a high efficiency for the detection of free neutrons capturing on the Gd. The delayed 8 MeV gamma cascades produced by these captures, in coincidence with a prompt positron signal, serve to uniquely identify electron antineutrinos interacting via inverse beta decay. Such coincidence detection can reduce backgrounds, allowing a large Gd-enhanced water Cherenkov detector to make the first observation of supernova relic neutrinos and high precision measurements of Japan's reactor antineutrino flux, while still allowing for all current physics studies to be continued. Now, a dedicated Gd test facility is operating in the Kamioka Mine. This new facility houses everything needed to successfully operate a Gd doped water Cherenkov detector. Successful running of this facility will demonstrate that adding Gd salt to SK is both safe for the detector and is capable of delivering the expected physics benefits.

  14. Cherenkov and Scintillation Light Separation in Organic Liquid Scintillators

    CERN Document Server

    Caravaca, J; Land, B J; Yeh, M; Gann, G D Orebi

    2016-01-01

    The CHErenkov / Scintillation Separation experiment (CHESS) has been used to demonstrate the separation of Cherenkov and scintillation light in both linear alkylbenzene (LAB) and LAB with 2g/L of PPO as a fluor (LAB/PPO). This is the first such demonstration for the more challenging LAB/PPO cocktail and improves on previous results for LAB. A time resolution of 338 +/- 12 ps FWHM results in an efficiency for identifying Cherenkov photons in LAB/PPO of 70 +/- 3% and 63 +/- 8% for time- and charge-based separation, respectively, with scintillation contamination of 36 +/- 5% and 38 +/- 4%. LAB/PPO data is consistent with a rise time of 0.75 +/- 0.25 ns.

  15. The GERDA muon veto Cherenkov detector

    International Nuclear Information System (INIS)

    The GERmanium Detector Array, GERDA, is a new experiment designed to examine the neutrinoless double beta decay 0νββ of 76Ge which has a lifetime of at least 1026 years and a single energy deposition of 2039 keV. To reach the goal of 10-3 background events/(keVkgy), several background reduction techniques like anti-coincidence and pulse shape analysis will be used. Cosmic muons can produce background in form of particles and radioactivity. To reject them, two independent detector systems will be integrated in GERDA. One of these is a Cherenkov muon veto detector, that uses the water tank around the cryostat in which the crystals will be operated. It is equipped with 66 photomultipliers (PMTs) with 8 in. diameter. The PMT distribution was found via extensive Monte Carlo studies to reach the highest efficiencies for dangerous muons (these are muons that cause an energy deposition of around 2 MeV in the germanium detectors), even though the PMTs cover less than 0.1% of the water tank surface. High efficiencies depend strongly on the amount of detected photons. For this, as many surfaces as possible will be covered with 'VM2000', a highly reflective foil from 3 M. This foil has a high reflectivity in a wide range of wavelength and it also shifts photons from the UV into the optical range. It, more or less, doubles the amount of detectable photons, because the photomultipliers used, have an detection maximum between 370 and 400 nm. Thus, a detection efficiency of 98% should be easily achieved.

  16. Applications of Digital Image Analysis in Experimental Mechanics

    OpenAIRE

    Lyngbye, J. : Ph.D.

    1992-01-01

    The present thesis "Application of Digital Image Analysis in Experimental Mechanics" has been prepared as a part of Janus Lyngbyes Ph.D. study during the period December 1988 to June 1992 at the Department of Building technology and Structural Engineering, University of Aalborg, Denmark. In this thesis attention will be focused on optimal use and analysis of the information of digital images. This is realized during investigation and application of parametric methods in digital image analysis...

  17. Applications of non-imaging micro-optic systems

    OpenAIRE

    Baker, Katherine Anne

    2012-01-01

    While imaging optics necessarily transmit a clear image of an object, non-imaging optics manipulate light in many different ways. Two important applications are illumination and concentration. In this thesis, I cover an application in each of these areas involving small-scale optics. Extremely low birth weight infants typically require intubation, but existing laryngoscopes for viewing the airway are not suited to this population. Small commercial cameras can fit within the required geometry,...

  18. Application of cone beam computed tomography in facial imaging science

    Institute of Scientific and Technical Information of China (English)

    Zacharias Fourie; Janalt Damstra; Yijin Ren

    2012-01-01

    The use of three-dimensional (3D) methods for facial imaging has increased significantly over the past years.Traditional 2D imaging has gradually being replaced by 3D images in different disciplines,particularly in the fields of orthodontics,maxillofacial surgery,plastic and reconstructive surgery,neurosurgery and forensic sciences.In most cases,3D facial imaging overcomes the limitations of traditional 2D methods and provides the clinician with more accurate information regarding the soft-tissues and the underlying skeleton.The aim of this study was to review the types of imaging methods used for facial imaging.It is important to realize the difference between the types of 3D imaging methods as application and indications thereof may differ.Since 3D cone beam computed tomography (CBCT) imaging will play an increasingly importanl role in orthodontics and orthognathic surgery,special emphasis should be placed on discussing CBCT applications in facial evaluations.

  19. TARGET 5: a new multi-channel digitizer with triggering capabilities for gamma-ray atmospheric Cherenkov telescopes

    CERN Document Server

    Albert, A; Kawashima, T; Murphy, M; Okumura, A; Quagliani, R; Sapozhnikov, L; Tajima, H; Tibaldo, L; Vandenbroucke, J; Wu, T

    2016-01-01

    TARGET~5 is a new application-specific integrated circuit (ASIC) of the TARGET family, designed for the readout of signals from photosensors in the cameras of imaging atmospheric Cherenkov telescopes (IACTs) for ground-based gamma-ray astronomy. TARGET~5 combines sampling and digitization on 16 signal channels with the formation of trigger signals based on the analog sum of groups of four channels. {\\rev We describe the ASIC architecture and performance.} TARGET~5 improves over the performance of the first-generation TARGET ASIC, achieving: tunable sampling frequency from {\\rev $1$~GSa/s}}; a dynamic range on the data path of 1.2 V with {\\mod effective dynamic range of 11}~bits and DC noise of ${\\sim}0.6$~mV; 3-dB bandwidth of 500 MHz; {\\rev crosstalk between adjacent channels $100$~p.e.} (assuming 4 mV per p.e.); and minimum stable trigger threshold of 20 mV (5 p.e.) with trigger noise of 5 mV (1.2 p.e.), {\\rev which is} mostly limited by {\\mod interference between trigger and sampling operations}. {\\mod TAR...

  20. Reconfigurable machine for applications in image and video compression

    Science.gov (United States)

    Hartenstein, Reiner W.; Becker, Juergen; Kress, Rainier; Reinig, Helmut; Schmidt, Karin

    1995-02-01

    This paper presents a reconfigurable machine for applications in image or video compression. The machine can be used stand alone or as a universal accelerator co-processor for desktop computers for image processing. It is well suited for image compression algorithms such as JPEG for still pictures or for encoding MPEG movies. It provides a much cheaper and more flexible hardware platform than special image compression ASICs and it can substantially accelerate desktop computing.

  1. Review of diffusion tensor imaging and its application in children

    International Nuclear Information System (INIS)

    Diffusion MRI is an imaging technique that uses the random motion of water to probe tissue microstructure. Diffusion tensor imaging (DTI) can quantitatively depict the organization and connectivity of white matter. Given the non-invasiveness of the technique, DTI has become a widely used tool for researchers and clinicians to examine the white matter of children. This review covers the basics of diffusion-weighted imaging and diffusion tensor imaging and discusses examples of their clinical application in children. (orig.)

  2. Review of diffusion tensor imaging and its application in children

    Energy Technology Data Exchange (ETDEWEB)

    Vorona, Gregory A. [Children' s Hospital of Richmond at Virginia Commonwealth University, Department of Radiology, Richmond, VA (United States); Berman, Jeffrey I. [Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

    2015-09-15

    Diffusion MRI is an imaging technique that uses the random motion of water to probe tissue microstructure. Diffusion tensor imaging (DTI) can quantitatively depict the organization and connectivity of white matter. Given the non-invasiveness of the technique, DTI has become a widely used tool for researchers and clinicians to examine the white matter of children. This review covers the basics of diffusion-weighted imaging and diffusion tensor imaging and discusses examples of their clinical application in children. (orig.)

  3. Application of electrical capacitance tomography for imaging industrial processes

    Institute of Scientific and Technical Information of China (English)

    DYAKOWSKI Tom

    2005-01-01

    Electrical tomography is, in certain cases, the most attractive method for real imaging of industrial processes, because of its inherent simplicity, rugged cons truction of the tomographer and high-speed capability. This paper presents examples illustrating applications of electrical tomography for imaging fluidized beds, bubble columns and pneumatic conveyors. Electrical tomography opens up new ways for processing, imaging and modelling multi-phase flows as shown by 2D and 3D images illustrating the various types of flow morphology.

  4. A template method for measuring the iron spectrum in cosmic rays with Cherenkov telescopes

    CERN Document Server

    Fleischhack, Henrike

    2015-01-01

    The energy-dependent abundance of elements in cosmic rays plays an important role in understanding their acceleration and propagation. Most current results are obtained either from direct measurements by balloon- or satellite-borne detectors, or from indirect measurements by air shower detector arrays on the Earth's surface. Imaging Atmospheric Cherenkov Telescopes (IACTs), used primarily for $\\gamma$-ray astronomy, can also be used for cosmic-ray physics. They are able to measure Cherenkov light emitted both by heavy nuclei and by secondary particles produced in air showers, and are thus sensitive to the charge and energy of cosmic ray particles with energies of tens to hundreds of TeV. A template-based method, which can be used to reconstruct the charge and energy of primary particles simultaneously from images taken by IACTs, will be introduced. Heavy nuclei, such as iron, can be separated from lighter cosmic rays with this method, and thus the abundance and spectrum of these nuclei can be measured in the ...

  5. From MAGIC to CTA: the INAF participation to Cherenkov Telescopes experiments for very high energy astrophysics .

    Science.gov (United States)

    Antonelli, L. A.; INAF MAGIC Collaboration

    The next decade can be considered the "golden age" of the Gamma Ray Astronomy with the two satellites for Gamma Ray Astronomy (AGILE and GLAST) in orbit. Therefore, thanks to many other X-ray experiments already in orbit (e.g. Swift, Chandra, NewtonXMM, etc.) it will be possible to image the Universe for the first time all over the electromagnetic spectrum almost contemporarily. The new generations of ground-based very high gamma-ray instruments are ready to extend the observed band also to the very high frequencies. Scientists from the Italian National Institute for Astrophysics (INAF) are involved in many, both space- and ground- based gamma ray experiments, and recently such an involvement has been largely improved in the field of the Imaging Atmospheric Cherenkov Telescopes (IACT). INAF is now member of the MAGIC collaboration and is participating to the realization of the second MAGIC telescope. MAGIC, as well other IACT experiments, is not operated as an observatory so a proper guest observer program does not exist. A consortium of European scientists (including INAF scientists) is thus now thinking to the design of a new research infrastructure: the Cherenkov Telescope Array (CTA). CTA is conceived to provide 10 times the sensitivity of current instruments, combined with increased flexibility and increased coverage from some 10 GeV to some 100 TeV. CTA will be operated as an observatory to serve a wider community of astronomer and astroparticle physicists.

  6. Cosmic ray composition measurements and cosmic ray background free gamma-ray observations with Cherenkov telescopes

    CERN Document Server

    Neronov, A; Vovk, Ie; Mirzoyan, R

    2016-01-01

    Muon component of extensive air showers (EAS) initiated by cosmic ray particles carries information on the primary particle identity. We show that the muon content of EAS could be measured in a broad energy range from 10-100 TeV up to ultra-high-energy cosmic ray range using wide field-of-view imaging atmospheric Cherenkov telescopes observing strongly inclined or nearly horizontal EAS from the ground of from high altitude. Cherenkov emission from muons in such EAS forms a distinct component (halo or tail) of the EAS image in the telescope camera. We show that detection of the muon signal could be used to measure composition of the cosmic ray spectrum in the energy ranges of the knee, the ankle and of the Galactic-to-extragalactic transition. It could also be used to veto the cosmic ray background in gamma-ray observations. This technique provides a possibility for up to two orders of magnitude improvement of sensitivity for gamma-ray flux in the energy band above 10 PeV, compared to KASCADE-Grande, and an or...

  7. Digital image analysis of palaeoenvironmental records and applications

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Environmental change signals in geological or biological records are commonly reflected on their reflecting or transmitting images. These environmental signals can be extracted through digital image analysis. The analysis principle involves section line selection, color value reading and calculating environmental proxy index along the section lines, layer identification, auto-chronology and investigation of structure evolution of growth bands. On detailed illustrations of the image technique, this note provides image analyzing procedures of coral, tree-ring and stalagmite records. The environmental implications of the proxy index from image analysis are accordingly given through application demonstration of the image technique.

  8. FACT-The first Cherenkov telescope using a G-APD camera for TeV gamma-ray astronomy

    Energy Technology Data Exchange (ETDEWEB)

    Anderhub, H. [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); Backes, M., E-mail: michael.backes@physik.tu-dortmund.d [Technische Universitaet Dortmund, D-44221 Dortmund (Germany); Biland, A.; Boller, A.; Braun, I. [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); Bretz, T. [Ecole Polytechnique Federale de Lausanne, CH-1015 (Switzerland); Commichau, S.; Commichau, V. [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); Domke, M. [Technische Universitaet Dortmund, D-44221 Dortmund (Germany); Dorner, D. [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); ISDC, Data Centre for Astrophysics, CH-1290 Versoix (Switzerland); Gendotti, A.; Grimm, O.; Gunten, H. von; Hildebrand, D.; Horisberger, U. [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); Koehne, J.-H. [Technische Universitaet Dortmund, D-44221 Dortmund (Germany); Kraehenbuehl, T.; Kranich, D. [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); Krumm, B. [Technische Universitaet Dortmund, D-44221 Dortmund (Germany); Lorenz, E. [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland)

    2011-05-21

    Geiger-mode Avalanche Photodiodes (G-APD) bear the potential to significantly improve the sensitivity of Imaging Air Cherenkov Telescopes (IACT). We are currently building the First G-APD Cherenkov Telescope (FACT) by refurbishing an old IACT with a mirror area of 9.5 square meters and are constructing a new, fine-pixelized camera using novel G-APDs. The main goal is to evaluate the performance of a complete system by observing very high energy gamma-rays from the Crab Nebula. This is an important field test to check the feasibility of G-APD-based cameras to replace at some time the PMT-based cameras of planned future IACTs like AGIS and CTA. In this article, we present the basic design of such a camera as well as some important details.

  9. A Cherenkov Radiation Detector with High Density Aerogels

    CERN Document Server

    Cremaldi, Lucien; Sonnek, Peter; Summers, Donald J; Reidy, Jim

    2009-01-01

    We have designed a threshold Cherenkov detector at the Rutherford-Appleton Laboratory to identify muons with momenta between 230 and 350 MeV/c. We investigated the properties of three aerogels for the design. The nominal indexes of refraction were n = 1.03, 1.07, 1.12, respectively. Two of the samples are of high density aerogel not commonly used for Cherenkov light detection. We present results of an examination of some optical properties of the aerogel samples and present basic test beam results.

  10. High speed decision electronics combined to a beam Cherenkov counter

    International Nuclear Information System (INIS)

    The Hypolit detector for identification of particles in high energy physics using the Cherenkov radiation, is based on an intensifier tube coupled to photomultipliers via a fiber-optic matrix. Cherenkov photons are focused into a ring; particle identification consists in calculating the ring radius. A fast and high level electronic system is associated to Hypolit. Besides deriving the radius, it allows a background rejection and achieves a momentum correction. This on line tagging contributes to build the WA89 trigger. Tuning is controlled with a micro-computer which makes the access to the heart of the system friendly-user

  11. Light-weight spherical mirrors for Cherenkov detectors

    CERN Document Server

    Cisbani, E; Colilli, S; Crateri, R; Cusanno, F; De Leo, R; Fratoni, R; Frullani, S; Garibaldi, F; Giuliani, F; Gricia, M; Iodice, M; Iommi, R; Lagamba, L; Lucentini, M; Mostarda, A; Nappi, E; Pierangeli, L; Santavenere, F; Urciuoli, G M; Vernin, P

    2003-01-01

    Light-weight spherical mirrors have been appositely designed and built for the gas threshold Cherenkov detectors of the two Hall A spectrometers. The mirrors are made of a 1 mm thick aluminized plexiglass sheet, reinforced by a rigid backing consisting of a phenolic honeycomb sandwiched between two carbon fiber mats epoxy glued. The produced mirrors have a thickness equivalent to 0.55% of radiation length, and an optical slope error of about 5.5 mrad. These characteristics make these mirrors suitable for the implementation in Cherenkov threshold detectors. Ways to improve the mirror features are also discussed in view of their possible employment in RICH detectors.

  12. Counting Extra Dimensions Magnetic Cherenkov Radiation from High Energy Neutrinos

    CERN Document Server

    Domokos, Gabor K; Kövesi-Domokos, S; Erdas, Andrea

    2003-01-01

    In theories which require a space of dimension d > 4, there is a natural mechanism of suppressing neutrino masses: while Standard Model fields are confined to a 3-brane, right handed neutrinos live in the bulk. Due to Kaluza-Klein excitations, the effective magnetic moments of neutrinos are enhanced. The effective magnetic moment is a monotonically growing function of the energy of the neutrino: consequently, high energy neutrinos can emit observable amounts of magnetic Cherenkov radiation. By observing the energy dependence of the magnetic Cherenkov radiation, one may be able to determine the number of compactified dimensions.

  13. Image Deblurring Using Derivative Compressed Sensing for Optical Imaging Application

    CERN Document Server

    Rostami, Mohammad; Wang, Zhou

    2011-01-01

    Reconstruction of multidimensional signals from the samples of their partial derivatives is known to be a standard problem in inverse theory. Such and similar problems routinely arise in numerous areas of applied sciences, including optical imaging, laser interferometry, computer vision, remote sensing and control. Though being ill-posed in nature, the above problem can be solved in a unique and stable manner, provided proper regularization and relevant boundary conditions. In this paper, however, a more challenging setup is addressed, in which one has to recover an image of interest from its noisy and blurry version, while the only information available about the imaging system at hand is the amplitude of the generalized pupil function (GPF) along with partial observations of the gradient of GPF's phase. In this case, the phase-related information is collected using a simplified version of the Shack-Hartmann interferometer, followed by recovering the entire phase by means of derivative compressed sensing. Su...

  14. Signal and image processing in medical applications

    CERN Document Server

    Kumar, Amit; Rahim, B Abdul; Kumar, D Sravan

    2016-01-01

    This book highlights recent findings on and analyses conducted on signals and images in the area of medicine. The experimental investigations involve a variety of signals and images and their methodologies range from very basic to sophisticated methods. The book explains how signal and image processing methods can be used to detect and forecast abnormalities in an easy-to-follow manner, offering a valuable resource for researchers, engineers, physicians and bioinformatics researchers alike.

  15. Perceptual digital imaging methods and applications

    CERN Document Server

    Lukac, Rastislav

    2012-01-01

    Visual perception is a complex process requiring interaction between the receptors in the eye that sense the stimulus and the neural system and the brain that are responsible for communicating and interpreting the sensed visual information. This process involves several physical, neural, and cognitive phenomena whose understanding is essential to design effective and computationally efficient imaging solutions. Building on advances in computer vision, image and video processing, neuroscience, and information engineering, perceptual digital imaging greatly enhances the capabilities of tradition

  16. Practical Applications of Synthetic Aperture Imaging

    OpenAIRE

    Nikolov, Svetoslav Ivanov; Kortbek, Jacob; Jensen, Jørgen Arendt

    2010-01-01

    Synthetic aperture imaging has been a focus of research for almost 3 decades. The research carried out at the Center for Fast Ultrasound Imaging has demonstrated that synthetic aperture focusing not only can be used in-vivo, but that it also yields superior B-mode and blood flow images. In the last years synthetic aperture focusing has moved from the lab to commercial products. The implementations vary in their scope and purpose. Some scanners use synthetic aperture imaging to improve the det...

  17. Versatile architecture for image recognition applications

    Science.gov (United States)

    Sacramone, Anthony; Scola, Joseph; Shazeer, Dov J.

    1992-03-01

    Architectures for the development of image recognition algorithms must support the implementation of systematic procedures for solving image recognition problems. All too often, designers develop image recognition architectures in an ad hoc fashion which lacks the structure to meet long term needs. Vendors typically supply customers with standard image processing libraries and display tools. Combining these tools and formulating development strategies have remained stumbling blocks in the design of complete image recognition algorithm development environments. In this paper, an architecture is presented which provides a well defined framework, and at the same time is sufficiently flexible to accommodate images of multiple sensor and data types. The primary components of the architecture are: ground-truthing, preprocessing (which includes image processing and segmentation), feature extraction, classification, and performance analysis. Powerful and well defined data structures are exploited for each of the primary components. Groups of programs called tasks manipulate one or more of these data structures, each task belonging to one of the primary components. Multiple tasks can be executed in an unsupervised mode over an entire database of images. Results are then subjected to performance analysis and feedback. A description of the primary components and how they are integrated to facilitate the rapid prototyping and development of image recognition algorithms is presented.

  18. Application of MATLAB in pretreatment technology of the underwater images

    International Nuclear Information System (INIS)

    The technology of underwater laser imaging has very important practical value at ocean exploitation such as underwater reconnaissance, target recognition, but its imagery is usually affected by speckle noise. A large number of background noise are brought to underwater laser image for the reasons of absorption and scattering of water, which is also the cause of noises and low contrast of the underwater images. In order to improve the effect of the images, digital image processing techniques are introduced. The result of underwater image processing acts as the input of feature extraction and recognition of the underwater objects. Histogram equalization, contrast enhancement, smoothing filtering are applied to process the blurry underwater laser images. The results of the experiment show these application of Matlab are effective and applicable. (authors)

  19. BOOK REVIEW: Infrared Thermal Imaging: Fundamentals, Research and Applications Infrared Thermal Imaging: Fundamentals, Research and Applications

    Science.gov (United States)

    Planinsic, Gorazd

    2011-09-01

    Ten years ago, a book with a title like this would be interesting only to a narrow circle of specialists. Thanks to rapid advances in technology, the price of thermal imaging devices has dropped sharply, so they have, almost overnight, become accessible to a wide range of users. As the authors point out in the preface, the growth of this area has led to a paradoxical situation: now there are probably more infrared (IR) cameras sold worldwide than there are people who understand the basic physics behind them and know how to correctly interpret the colourful images that are obtained with these devices. My experience confirms this. When I started using the IR camera during lectures on the didactics of physics, I soon realized that I needed more knowledge, which I later found in this book. A wide range of potential readers and topical areas provides a good motive for writing a book such as this one, but it also represents a major challenge for authors, as compromises in the style of writing and choice of topics are required. The authors of this book have successfully achieved this, and indeed done an excellent job. This book addresses a wide range of readers, from engineers, technicians, and physics and science teachers in schools and universities, to researchers and specialists who are professionally active in the field. As technology in this area has made great progress in recent times, this book is also a valuable guide for those who opt to purchase an infrared camera. Chapters in this book could be divided into three areas: the fundamentals of IR thermal imaging and related physics (two chapters); IR imaging systems and methods (two chapters) and applications, including six chapters on pedagogical applications; IR imaging of buildings and infrastructure, industrial applications, microsystems, selected topics in research and industry, and selected applications from other fields. All chapters contain numerous colour pictures and diagrams, and a rich list of relevant

  20. Emerging applications of conjugated polymers in molecular imaging.

    Science.gov (United States)

    Li, Junwei; Liu, Jie; Wei, Chen-Wei; Liu, Bin; O'Donnell, Matthew; Gao, Xiaohu

    2013-10-28

    In recent years, conjugated polymers have attracted considerable attention from the imaging community as a new class of contrast agent due to their intriguing structural, chemical, and optical properties. Their size and emission wavelength tunability, brightness, photostability, and low toxicity have been demonstrated in a wide range of in vitro sensing and cellular imaging applications, and have just begun to show impact in in vivo settings. In this Perspective, we summarize recent advances in engineering conjugated polymers as imaging contrast agents, their emerging applications in molecular imaging (referred to as in vivo uses in this paper), as well as our perspectives on future research.

  1. Imaging-Genetics Applications in Child Psychiatry

    Science.gov (United States)

    Pine, Daniel S.; Ernst, Monique; Leibenluft, Ellen

    2010-01-01

    Objective: To place imaging-genetics research in the context of child psychiatry. Method: A conceptual overview is provided, followed by discussion of specific research examples. Results: Imaging-genetics research is described linking brain function to two specific genes, for the serotonin-reuptake-transporter protein and a monoamine oxidase…

  2. Photoacoustic tomography: applications for atherosclerosis imaging

    Science.gov (United States)

    Sangha, Gurneet S.; Goergen, Craig J.

    2016-08-01

    Atherosclerosis is a debilitating condition that increases a patient’s risk for intermittent claudication, limb amputation, myocardial infarction, and stroke, thereby causing approximately 50% of deaths in the western world. Current diagnostic imaging techniques, such as ultrasound, digital subtraction angiography, computed tomography angiography, magnetic resonance angiography, and optical imaging remain suboptimal for detecting development of early stage plaques. This is largely due to the lack of compositional information, penetration depth, and/or clinical efficiency of these traditional imaging techniques. Photoacoustic imaging has emerged as a promising modality that could address some of these limitations to improve the diagnosis and characterization of atherosclerosis-related diseases. Photoacoustic imaging uses near-infrared light to induce acoustic waves, which can be used to recreate compositional images of tissue. Recent developments in photoacoustic techniques show its potential in noninvasively characterizing atherosclerotic plaques deeper than traditional optical imaging approaches. In this review, we discuss the significance and development of atherosclerosis, current and novel clinical diagnostic methods, and recent works that highlight the potential of photoacoustic imaging for both experimental and clinical studies of atherosclerosis.

  3. Comparison of Cherenkov excited fluorescence and phosphorescence molecular sensing from tissue with external beam irradiation.

    Science.gov (United States)

    Lin, Huiyun; Zhang, Rongxiao; Gunn, Jason R; Esipova, Tatiana V; Vinogradov, Sergei; Gladstone, David J; Jarvis, Lesley A; Pogue, Brian W

    2016-05-21

    Ionizing radiation delivered by a medical linear accelerator (LINAC) generates Cherenkov emission within the treated tissue. A fraction of this light, in the 600-900 nm wavelength region, propagates through centimeters of tissue and can be used to excite optical probes in vivo, enabling molecular sensing of tissue analytes. The success of isolating the emission signal from this Cherenkov excitation background is dependent on key factors such as: (i) the Stokes shift of the probe spectra; (ii) the excited state lifetime; (iii) the probe concentration; (iv) the depth below the tissue surface; and (v) the radiation dose used. Previous studies have exclusively focused on imaging phosphorescent dyes, rather than fluorescent dyes. However there are only a few biologically important phosphorescent dyes and yet in comparison there are thousands of biologically relevant fluorescent dyes. So in this study the focus was a study of efficacy of Cherenkov-excited luminescence using fluorescent commercial near-infrared probes, IRDye 680RD, IRDye 700DX, and IRDye 800CW, and comparing them to the well characterized phosphorescent probe Oxyphor PtG4, an oxygen sensitive dye. Each probe was excited by Cherenkov light from a 6 MV external radiation beam, and measured in continuous wave or time-gated modes. The detection was performed by spectrally resolving the luminescence signals, and measuring them with spectrometer-based separation on an ICCD detector. The results demonstrate that IRDye 700DX and PtG4 allowed for the maximal signal to noise ratio. In the case of the phosphorescent probe, PtG4, with emission decays on the microsecond (μs) time scale, time-gated acquisition was possible, and it allowed for higher efficacy in terms of the probe concentration and detection depth. Phantoms containing the probe at 5 mm depth could be detected at concentrations down to the nanoMolar range, and at depths into the tissue simulating phantom near 3 cm. In vivo studies showed that 5

  4. Comparison of Cherenkov excited fluorescence and phosphorescence molecular sensing from tissue with external beam irradiation

    Science.gov (United States)

    Lin, Huiyun; Zhang, Rongxiao; Gunn, Jason R.; Esipova, Tatiana V.; Vinogradov, Sergei; Gladstone, David J.; Jarvis, Lesley A.; Pogue, Brian W.

    2016-05-01

    Ionizing radiation delivered by a medical linear accelerator (LINAC) generates Cherenkov emission within the treated tissue. A fraction of this light, in the 600–900 nm wavelength region, propagates through centimeters of tissue and can be used to excite optical probes in vivo, enabling molecular sensing of tissue analytes. The success of isolating the emission signal from this Cherenkov excitation background is dependent on key factors such as: (i) the Stokes shift of the probe spectra; (ii) the excited state lifetime; (iii) the probe concentration; (iv) the depth below the tissue surface; and (v) the radiation dose used. Previous studies have exclusively focused on imaging phosphorescent dyes, rather than fluorescent dyes. However there are only a few biologically important phosphorescent dyes and yet in comparison there are thousands of biologically relevant fluorescent dyes. So in this study the focus was a study of efficacy of Cherenkov-excited luminescence using fluorescent commercial near-infrared probes, IRDye 680RD, IRDye 700DX, and IRDye 800CW, and comparing them to the well characterized phosphorescent probe Oxyphor PtG4, an oxygen sensitive dye. Each probe was excited by Cherenkov light from a 6 MV external radiation beam, and measured in continuous wave or time-gated modes. The detection was performed by spectrally resolving the luminescence signals, and measuring them with spectrometer-based separation on an ICCD detector. The results demonstrate that IRDye 700DX and PtG4 allowed for the maximal signal to noise ratio. In the case of the phosphorescent probe, PtG4, with emission decays on the microsecond (μs) time scale, time-gated acquisition was possible, and it allowed for higher efficacy in terms of the probe concentration and detection depth. Phantoms containing the probe at 5 mm depth could be detected at concentrations down to the nanoMolar range, and at depths into the tissue simulating phantom near 3 cm. In vivo studies showed that 5

  5. Characterizing the radiation response of Cherenkov glass detectors with isotopic sources

    Energy Technology Data Exchange (ETDEWEB)

    Hayward, J P [University of Tennessee, Knoxville (UTK); Hobbs, C. L. [University of Tennessee, Knoxville (UTK); Bell, Zane W [ORNL; Boatner, Lynn A [ORNL; Johnson, Rose E [ORNL; Ramey, Joanne Oxendine [ORNL; Jellison Jr, Gerald Earle [ORNL; Lillard, Cole R [ORNL; Ramey, Lucas A [ORNL

    2012-01-01

    Abstract Cherenkov detectors are widely used for particle identification and threshold detectors in high-energy physics. Glass Cherenkov detectors that are sensitive to beta emissions originating from neutron activation have been demonstrated recently as a potential replacement for activation foils. In this work, we set the groundwork to evaluate large Cherenkov glass detectors for sensitivity to MeV photons through first understanding the measured response of small Cherenkov glass detectors to isotopic gamma-ray sources. Counting and pulse height measurements are acquired with reflected glass Cherenkov detectors read out with a photomultiplier tube. Simulation was used to inform our understanding of the measured results. This simulation included radioactive source decay, radiation interaction, Cherenkov light generation, optical ray tracing, and photoelectron production. Implications for the use of Cherenkov glass detectors to measure low energy gammaray response are discussed.

  6. Efficient Image Blur in Web-Based Applications

    DEFF Research Database (Denmark)

    Kraus, Martin

    2010-01-01

    Scripting languages require the use of high-level library functions to implement efficient image processing; thus, real-time image blur in web-based applications is a challenging task unless specific library functions are available for this purpose. We present a pyramid blur algorithm, which can...... be implemented using a subimage copy function, and evaluate its performance with various web browsers in comparison to an infinite impulse response filter. While this pyramid algorithm was first proposed for GPU-based image processing, its applicability to web-based applications indicates that some GPU...

  7. Mathematical Morphology Techniques For Image Processing Applications In Biomedical Imaging

    Science.gov (United States)

    Bartoo, Grace T.; Kim, Yongmin; Haralick, Robert M.; Nochlin, David; Sumi, Shuzo M.

    1988-06-01

    Mathematical morphology operations allow object identification based on shape and are useful for grouping a cluster of small objects into one object. Because of these capabilities, we have implemented and evaluated this technique for our study of Alzheimer's disease. The microscopic hallmark of Alzheimer's disease is the presence of brain lesions known as neurofibrillary tangles and senile plaques. These lesions have distinct shapes compared to normal brain tissue. Neurofibrillary tangles appear as flame-shaped structures, whereas senile plaques appear as circular clusters of small objects. In order to quantitatively analyze the distribution of these lesions, we have developed and applied the tools of mathematical morphology on the Pixar Image Computer. As a preliminary test of the accuracy of the automatic detection algorithm, a study comparing computer and human detection of senile plaques was performed by evaluating 50 images from 5 different patients. The results of this comparison demonstrates that the computer counts correlate very well with the human counts (correlation coefficient = .81). Now that the basic algorithm has been shown to work, optimization of the software will be performed to improve its speed. Also future improvements such as local adaptive thresholding will be made to the image analysis routine to further improve the systems accuracy.

  8. Multimodality Image Fusion-Guided Procedures: Technique, Accuracy, and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Abi-Jaoudeh, Nadine, E-mail: naj@mail.nih.gov [National Institutes of Health, Radiology and Imaging Sciences (United States); Kruecker, Jochen, E-mail: jochen.kruecker@philips.com [Philips Research North America (United States); Kadoury, Samuel, E-mail: samuel.kadoury@polymtl.ca [Ecole Polytechnique de Montreal, Department of Computer and Software Engineering, Institute of Biomedical Engineering (Canada); Kobeiter, Hicham, E-mail: hicham.kobeiter@gmail.com [CHU Henri Mondor, UPEC, Departments of Radiology and d' imagrie medicale (France); Venkatesan, Aradhana M., E-mail: VenkatesanA@cc.nih.gov; Levy, Elliot, E-mail: levyeb@cc.nih.gov; Wood, Bradford J., E-mail: bwood@cc.nih.gov [National Institutes of Health, Radiology and Imaging Sciences (United States)

    2012-10-15

    Personalized therapies play an increasingly critical role in cancer care: Image guidance with multimodality image fusion facilitates the targeting of specific tissue for tissue characterization and plays a role in drug discovery and optimization of tailored therapies. Positron-emission tomography (PET), magnetic resonance imaging (MRI), and contrast-enhanced computed tomography (CT) may offer additional information not otherwise available to the operator during minimally invasive image-guided procedures, such as biopsy and ablation. With use of multimodality image fusion for image-guided interventions, navigation with advanced modalities does not require the physical presence of the PET, MRI, or CT imaging system. Several commercially available methods of image-fusion and device navigation are reviewed along with an explanation of common tracking hardware and software. An overview of current clinical applications for multimodality navigation is provided.

  9. Application of optical coherence tomography based microangiography for cerebral imaging

    Science.gov (United States)

    Baran, Utku; Wang, Ruikang K.

    2016-03-01

    Requirements of in vivo rodent brain imaging are hard to satisfy using traditional technologies such as magnetic resonance imaging and two-photon microscopy. Optical coherence tomography (OCT) is an emerging tool that can easily reach at high speeds and provide high resolution volumetric images with a relatively large field of view for rodent brain imaging. Here, we provide the overview of recent developments of functional OCT based imaging techniques for neuroscience applications on rodents. Moreover, a summary of OCT-based microangiography (OMAG) studies for stroke and traumatic brain injury cases on rodents are provided.

  10. Multi-sensor image fusion and its applications

    CERN Document Server

    Blum, Rick S

    2005-01-01

    Taking another lesson from nature, the latest advances in image processing technology seek to combine image data from several diverse types of sensors in order to obtain a more accurate view of the scene: very much the same as we rely on our five senses. Multi-Sensor Image Fusion and Its Applications is the first text dedicated to the theory and practice of the registration and fusion of image data, covering such approaches as statistical methods, color-related techniques, model-based methods, and visual information display strategies.After a review of state-of-the-art image fusion techniques,

  11. In vivo Coherent Raman Imaging for Neuroscience Applications

    Science.gov (United States)

    Cote, Daniel

    2010-08-01

    The use of coherent Raman imaging is described for applications in neuroscience. Myelin imaging of the spinal cord can be performed with Raman imaging through the use of the vibration in carbon-hydrogen bonds, dominant in lipids. First, we demonstrate in vivo histomorphometry in live animal for characterization of myelin-related nervous system pathologies. This is used to characterize spinal cord health during multiple sclerosis. Second, Raman spectroscopy of tissue is discussed. We discuss the challenges that live animal imaging brings, together with important aspects of coherent Raman imaging in tissue.

  12. The ARCADE Raman Lidar System for the Cherenkov Telescope Array

    CERN Document Server

    Valore, Laura; Doro, Michele; Iarlori, Marco; Rizi, Vincenzo; Tonachini, Aurelio Siro; Vallania, Piero

    2015-01-01

    The Cherenkov Telescope Array (CTA) is the next generation of ground-based very high energy gamma-ray instruments; the facility will be organized in two arrays, one for each hemisphere. The atmospheric calibration of the CTA telescopes is a critical task. The atmosphere affects the measured Cherenkov yield in several ways: the air-shower development itself, the variation of the Cherenkov angle with altitude, the loss of photons due to scattering and absorption of Cherenkov light out of the camera field-of-view and the scattering of photons into the camera. In this scenario, aerosols are the most variable atmospheric component in time and space and therefore need a continuous monitoring. Lidars are among the most used instruments in atmospheric physics to measure the aerosol attenuation profiles of light. The ARCADE Lidar system is a very compact and portable Raman Lidar system that has been built within the FIRB 2010 grant and is currently taking data in Lamar, Colorado. The ARCADE Lidar is proposed to operat...

  13. Detection of atmospheric Cherenkov radiation using solar heliostat mirrors

    Science.gov (United States)

    Ong, R. A.; Bhattacharya, D.; Covault, C. E.; Dixon, D. D.; Gregorich, D. T.; Hanna, D. S.; Oser, S.; Québert, J.; Smith, D. A.; Tümer, O. T.; Zych, A. D.

    1996-10-01

    There is considerable interest world-wide in developing large area atmospheric Cherenkov detectors for ground-based gamma-ray astronomy. This interest stems, in large part, from the fact that the gamma-ray energy region between 20 and 250 GeV is unexplored by any experiment. Atmospheric Cherenkov detectors offer a possible way to explore this region, but large photon collection areas are needed to achieve low energy thresholds. We are developing an experiment using the heliostat mirrors of a solar power plant as the primary collecting element. As part of this development, we built a detector using four heliostat mirrors, a secondary Fresnel lens, and a fast photon detection system. In November 1994, we used this detector to record atmospheric Cherenkov radiation produced by cosmic ray particles showering in the atmosphere. The detected rate of cosmic ray events was consistent with an energy threshold near 1 TeV. The data presented here represent the first detection of atmospheric Cherenkov radiation using solar heliostats viewed from a central tower.

  14. Application of ASAP in integral imaging

    Science.gov (United States)

    Wang, Hong-xia; Xu, Zhi-li; Wen, Shao-jie; Wu, Chun-hong

    2012-10-01

    Integral imaging (II) is a technique that is capable of displaying 3D images with continuous parallax in full natural color. At present Integral Imaging is a popular three-dimensional imaging technology. It is becoming the most perspective technique in developing next generation three-dimensional TV (3DTV) and visualization field due to its outstanding advantages. The micro-lens array is used in recording and replaying 3D scene information in this technique with true color, simply reconstruction and non-relevant light source. In order to research really many precision instrument are required. But the price is too high to set up a complicated authentic imaging system. In the same time the imaging condition is very difficult to satisfy. ASAP (Advanced System Analysis Program) is an advanced imitates optical software to solve reality optical questions. It is used in many research territories. In this paper the ASAP software is proposed to simulate and model the micro-lens array sheet. The ray tracing and energy distribution is completed. According to the study results we can optimum lens designing through modifying the focal length, aperture size and imaging position. We hope the study cost can be reduced and the efficiency can be improved through the use of simulation method to optical design software ASAP.

  15. APPLICATION OF IMAGE MANIPULATION FOR CAVITATION ANALYZING

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new method, which is called image manipulation,is introduced to analyze the cavitation of flow field for the first time. As the complexity of the cavitation development must be considering,only the method of image manipulation can calculate the strength of the cavitation more accurately. This method based on wavelet transform is used to eliminate the noise. The area of the cavitations is deduced to serve as the strength of cavitation. The method is applied in an example of inducer's rotating cavitation. The results show that using image manipulation can get the accurate date of cavitation with ease,and the reason of the inducer shaft's vibration is uncovered clearly.

  16. Applications of thermal imaging in avian science

    OpenAIRE

    McCafferty, D. J.

    2013-01-01

    Thermal imaging, or infrared thermography, has been used in avian science since the 1960s. More than 30 species of birds, ranging in size from passerines to ratites, have been studied using this technology. The main strength of this technique is that it is a non-invasive and non-contact method of measuring surface temperature. Its limitations and measurement errors are well understood and suitable protocols have been developed for a variety of experimental settings. Thermal imaging has been u...

  17. Simulated gamma-ray pulse profile of the Crab pulsar with the Cherenkov Telescope Array

    Science.gov (United States)

    Burtovoi, A.; Zampieri, L.

    2016-07-01

    We present simulations of the very high energy (VHE) gamma-ray light curve of the Crab pulsar as observed by the Cherenkov Telescope Array (CTA). The CTA pulse profile of the Crab pulsar is simulated with the specific goal of determining the accuracy of the position of the interpulse. We fit the pulse shape obtained by the Major Atmospheric Gamma-Ray Imaging Cherenkov (MAGIC) telescope with a three-Gaussian template and rescale it to account for the different CTA instrumental and observational configurations. Simulations are performed for different configurations of CTA and for the ASTRI (Astrofisica con Specchi a Tecnologia Replicante Italiana) mini-array. The northern CTA configuration will provide an improvement of a factor of ˜3 in accuracy with an observing time comparable to that of MAGIC (73 h). Unless the VHE spectrum above 1 TeV behaves differently from what we presently know, unreasonably long observing times are required for a significant detection of the pulsations of the Crab pulsar with the high-energy-range sub-arrays. We also found that an independent VHE timing analysis is feasible with Large Size Telescopes. CTA will provide a significant improvement in determining the VHE pulse shape parameters necessary to constrain theoretical models of the gamma-ray emission of the Crab pulsar. One of such parameters is the shift in phase between peaks in the pulse profile at VHE and in other energy bands that, if detected, may point to different locations of the emission regions.

  18. SST-GATE: A dual mirror telescope for the Cherenkov Telescope Array

    CERN Document Server

    Zech, A; Blake, S; Boisson, C; Costille, C; De-Frondat, F; Dournaux, J -L; Dumas, D; Fasola, G; Greenshaw, T; Hervet, O; Huet, J -M; Laporte, P; Rulten, C; Savoie, D; Sayede, F; Schmoll, J

    2013-01-01

    The Cherenkov Telescope Array (CTA) will be the world's first open observatory for very high energy gamma-rays. Around a hundred telescopes of different sizes will be used to detect the Cherenkov light that results from gamma-ray induced air showers in the atmosphere. Amongst them, a large number of Small Size Telescopes (SST), with a diameter of about 4 m, will assure an unprecedented coverage of the high energy end of the electromagnetic spectrum (above ~1TeV to beyond 100 TeV) and will open up a new window on the non-thermal sky. Several concepts for the SST design are currently being investigated with the aim of combining a large field of view (~9 degrees) with a good resolution of the shower images, as well as minimizing costs. These include a Davies-Cotton configuration with a Geiger-mode avalanche photodiode (GAPD) based camera, as pioneered by FACT, and a novel and as yet untested design based on the Schwarzschild-Couder configuration, which uses a secondary mirror to reduce the plate-scale and to all...

  19. Prototype of a production system for Cherenkov Telescope Array with DIRAC

    CERN Document Server

    Arrabito, L; Haupt, A; Graciani Diaz, R; Stagni, F; Tsaregorodtsev, A

    2015-01-01

    The Cherenkov Telescope Array (CTA) — an array of many tens of Imaging Atmospheric Cherenkov Telescopes deployed on an unprecedented scale — is the next generation instrument in the field of very high energy gamma-ray astronomy. CTA will operate as an open observatory providing data products to the scientific community. An average data stream of about 10 GB/s for about 1000 hours of observation per year, thus producing several PB/year, is expected. Large CPU time is required for data-processing as well for massive Monte Carlo simulations needed for detector calibration purposes. The current CTA computing model is based on a distributed infrastructure for the archive and the data off-line processing. In order to manage the off-line data-processing in a distributed environment, CTA has evaluated the DIRAC (Distributed Infrastructure with Remote Agent Control) system, which is a general framework for the management of tasks over distributed heterogeneous computing environments. In particular, a production sy...

  20. Expected performance of the ASTRI mini-array in the framework of the Cherenkov Telescope Array

    Science.gov (United States)

    Di Pierro, F.; Bigongiari, C.; Stamerra, A.; Vallania, P.; ASTRI Collaboration; CTA Consortium, the

    2016-05-01

    The Cherenkov Telescope Array (CTA) Observatory is a world-wide project for the ground-based study of the sources of the highest energy photons. By adopting telescopes of three different size categories it will cover the wide energy range from tens of GeV up to hundreds of TeV, limited only by the source physical properties and the gamma absorption by the extragalactic background light. The full sky coverage will be assured by two arrays, one in each hemisphere. An array of small size telescopes (SSTs), covering the highest energy region (3-100 TeV), the region most flux limited for current imaging atmospheric Cherenkov telescopes, is planned to be deployed at the southern CTA site in the first phase of the CTA project. The ASTRI collaboration has developed a prototype of a dual mirror SST equipped with a SiPM-based focal plane (ASTRI SST-2M) and has proposed to install a mini-array of nine of such telescopes at the CTA southern site (the ASTRI mini-array). In order to study the expected performance and the scientific capabilities of different telescope configurations, full Monte Carlo (MC) simulations of the shower development in the atmosphere for both gammas and hadronic background have been performed, followed by detailed simulations of the telescopes. In this work the expected performance of the ASTRI mini-array in terms of sensitivity, angular and energy resolution are presented and discussed.

  1. 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...

  2. The IFAE/UAB and LUPM Raman LIDARs for Cherenkov Telescope Array Observatory

    CERN Document Server

    López-Oramas, A; Bigas, O Blanch; Boix, J; Da Deppo, V; Doro, M; Font, L; Garrido, D; Gaug, M; Martínez, M; Vasileiadis, G

    2013-01-01

    The Cherenkov Telescope Array (CTA) is the next generation of Imaging Atmospheric Cherenkov Telescopes. It will reach a sensitivity and an energy resolution with no precendent in very high energy gamma-ray astronomy. In order to achieve this goal, the systematic uncertainties derived from the atmospheric conditions shall be reduced to the minimum. Different instruments may help account for these uncertainties. The Barcelona IFAE/UAB (acronyms for Institut de F\\'isica d'Altes Energies and Universitat Aut\\`onoma de Barcelona, respectively) and the Montpellier LUPM (Laboratoire Univers et Particules de Montpellier) groups are building Raman LIDARs, devices which can reduce the systematic uncertainties in the reconstruction of the gamma-ray energies from 20$%$ down to 5$%$. The Raman LIDARs subject of this work have coaxial 1.8 m mirrors with a Nd-YAG laser each. A liquid light-guide collects the light at the focal plane and transports it to the readout system. We are developping a monochromator with the purpose ...

  3. The Cherenkov Telescope Array On-Site integral sensitivity: observing the Crab

    CERN Document Server

    Fioretti, Valentina; Schussler, Fabian

    2016-01-01

    The Cherenkov Telescope Array (CTA) is the future large observatory in the very high energy (VHE) domain. Operating from 20 GeV to 300 TeV, it will be composed of tens of Imaging Air Cherenkov Telescopes (IACTs) displaced in a large area of a few square kilometers in both the southern and northern hemispheres. The CTA/DATA On-Site Analysis (OSA) is the system devoted to the development of dedicated pipelines and algorithms to be used at the CTA site for the reconstruction, data quality monitoring, science monitoring and realtime science alerting during observations. The OSA integral sensitivity is computed here for the most studied source at Gamma-rays, the Crab Nebula, for a set of exposures ranging from 1000 seconds to 50 hours, using the full CTA Southern array. The reason for the Crab Nebula selection as the first example of OSA integral sensitivity is twofold: (i) this source is characterized by a broad spectrum covering the entire CTA energy range; (ii) it represents, at the time of writing, the standar...

  4. Developments of a new mirror technology for the Cherenkov Telescope Array

    CERN Document Server

    ,

    2015-01-01

    The Cherenkov Telescope Array (CTA) observatory for very high-energy gamma rays will consist of about a hundred of imaging atmospheric Cherenkov telescopes (IACTs) of different size with a total reflective area of about 10,000 m$^2$. Here we present a novel technology for the production of IACT mirrors that has been developed in the Institute of Nuclear Physics PAS in Krakow, Poland. The mirrors are made by cold-slumping of the front reflecting aluminium-coated panel and the rear panel interspaced with aluminium spacers. Each panel is built of two glass panels laminated with a layer of a fibreglass tissue in between for reinforcement of the structure against mechanical damage. The mirror structure is open and does not require a perfect sealing needed in closed-type designs. It prohibits water to be trapped inside and enables a proper ventilation of the mirror. Full-size hexagonal prototype mirrors produced for the medium-sized CTA telescopes will be presented together with the results of recent comprehensive ...

  5. The design and performance of a prototype water Cherenkov optical time-projection chamber

    CERN Document Server

    Oberla, E

    2015-01-01

    A first experimental test of tracking relativistic charged particles by `drifting' Cherenkov photons in a water-based optical time-projection chamber (OTPC) has been performed at the Fermilab Test Beam Facility. The prototype OTPC detector consists of a 77~cm long, 28~cm diameter, 40~kg cylindrical water mass instrumented with a combination of commercial $5.1\\times5.1$~cm$^2$ micro-channel plate photo-multipliers (MCP-PMT) and $6.7\\times6.7$~cm$^2$ mirrors. Five MCP-PMTs are installed in two columns along the OTPC cylinder in a small-angle stereo configuration. A mirror is mounted opposite each MCP-PMT on the far side of the detector cylinder, effectively doubling the photo-detection efficiency and providing a time-resolved image of the Cherenkov light on the opposing wall. Each MCP-PMT is coupled to an anode readout consisting of thirty 50 Ohm microstrips. A 180-channel data acquisition system digitizes the MCP-PMT signals on one end of the microstrips using the PSEC4 waveform sampling-and-digitizing chip op...

  6. High-energy proton imaging for biomedical applications

    Science.gov (United States)

    Prall, M.; Durante, M.; Berger, T.; Przybyla, B.; Graeff, C.; Lang, P. M.; LaTessa, C.; Shestov, L.; Simoniello, P.; Danly, C.; Mariam, F.; Merrill, F.; Nedrow, P.; Wilde, C.; Varentsov, D.

    2016-01-01

    The charged particle community is looking for techniques exploiting proton interactions instead of X-ray absorption for creating images of human tissue. Due to multiple Coulomb scattering inside the measured object it has shown to be highly non-trivial to achieve sufficient spatial resolution. We present imaging of biological tissue with a proton microscope. This device relies on magnetic optics, distinguishing it from most published proton imaging methods. For these methods reducing the data acquisition time to a clinically acceptable level has turned out to be challenging. In a proton microscope, data acquisition and processing are much simpler. This device even allows imaging in real time. The primary medical application will be image guidance in proton radiosurgery. Proton images demonstrating the potential for this application are presented. Tomographic reconstructions are included to raise awareness of the possibility of high-resolution proton tomography using magneto-optics. PMID:27282667

  7. High-energy proton imaging for biomedical applications

    Science.gov (United States)

    Prall, M.; Durante, M.; Berger, T.; Przybyla, B.; Graeff, C.; Lang, P. M.; Latessa, C.; Shestov, L.; Simoniello, P.; Danly, C.; Mariam, F.; Merrill, F.; Nedrow, P.; Wilde, C.; Varentsov, D.

    2016-06-01

    The charged particle community is looking for techniques exploiting proton interactions instead of X-ray absorption for creating images of human tissue. Due to multiple Coulomb scattering inside the measured object it has shown to be highly non-trivial to achieve sufficient spatial resolution. We present imaging of biological tissue with a proton microscope. This device relies on magnetic optics, distinguishing it from most published proton imaging methods. For these methods reducing the data acquisition time to a clinically acceptable level has turned out to be challenging. In a proton microscope, data acquisition and processing are much simpler. This device even allows imaging in real time. The primary medical application will be image guidance in proton radiosurgery. Proton images demonstrating the potential for this application are presented. Tomographic reconstructions are included to raise awareness of the possibility of high-resolution proton tomography using magneto-optics.

  8. Stellar intensity interferometry over kilometer baselines: Laboratory simulation of observations with the Cherenkov Telescope Array

    CERN Document Server

    Dravins, Dainis

    2014-01-01

    A long-held astronomical vision is to realize diffraction-limited optical aperture synthesis over kilometer baselines. This will enable imaging of stellar surfaces and their environments, show their evolution over time, and reveal interactions of stellar winds and gas flows in binary star systems. An opportunity is now opening up with the large telescope arrays primarily erected for measuring Cherenkov light in air induced by gamma rays. With suitable software, such telescopes could be electronically connected and used also for intensity interferometry. With no optical connection between the telescopes, the error budget is set by the electronic time resolution of a few nanoseconds. Corresponding light-travel distances are on the order of one meter, making the method practically insensitive to atmospheric turbulence or optical imperfections, permitting both very long baselines and observing at short optical wavelengths. Theoretical modeling has shown how stellar surface images can be retrieved from such observ...

  9. Evolution of ground-based gamma-ray astronomy from the early days to the Cherenkov Telescope Arrays

    Science.gov (United States)

    Hillas, A. M.

    2013-03-01

    Most of what we know of cosmic gamma rays has come from spacecraft, but at energies above tens of GeV it has become possible to make observations with ground-based detectors of enormously greater collecting area. In recent years one such detector type, the cluster of imaging air Cherenkov telescopes, has reached a very productive state, whilst several alternative approaches have been explored, including converted solar power collectors and novel high-altitude particle shower detectors which promised to extend the energy range covered. Key examples of development from 1952 to 2011 are followed, noting the problems and discoveries that stimulated the current work, explaining the logic of the alternative approaches that were taken. The merits of the current major Cherenkov observatories and of other viable detectors are examined and compared, with examples of the astrophysical information they are beginning to provide. The detectors are still evolving, as we still do not understand the processes onto which the gamma rays provide a window. These include the acceleration of Galactic cosmic rays (in particular, the wide-band spectra of radiation from some individual supernova remnants are still hard to interpret), the highly relativistic and variable jets from active galactic nuclei, and aspects of the electrodynamics of pulsars. Larger groups of Cherenkov telescopes still offer the possibility of an increase in power of the technique for resolvable Galactic sources especially.

  10. Optimizing signal and image processing applications using Intel libraries

    Science.gov (United States)

    Landré, Jérôme; Truchetet, Frédéric

    2007-01-01

    This paper presents optimized signal and image processing libraries from Intel Corporation. Intel Performance Primitives (IPP) is a low-level signal and image processing library developed by Intel Corporation to optimize code on Intel processors. Open Computer Vision library (OpenCV) is a high-level library dedicated to computer vision tasks. This article describes the use of both libraries to build flexible and efficient signal and image processing applications.

  11. Plugin procedure in segmentation and application to hyperspectral image segmentation

    OpenAIRE

    Girard, R

    2010-01-01

    In this article we give our contribution to the problem of segmentation with plug-in procedures. We give general sufficient conditions under which plug in procedure are efficient. We also give an algorithm that satisfy these conditions. We give an application of the used algorithm to hyperspectral images segmentation. Hyperspectral images are images that have both spatial and spectral coherence with thousands of spectral bands on each pixel. In the proposed procedure we combine a reduction di...

  12. On digital image processing technology and application in geometric measure

    Science.gov (United States)

    Yuan, Jiugen; Xing, Ruonan; Liao, Na

    2014-04-01

    Digital image processing technique is an emerging science that emerging with the development of semiconductor integrated circuit technology and computer science technology since the 1960s.The article introduces the digital image processing technique and principle during measuring compared with the traditional optical measurement method. It takes geometric measure as an example and introduced the development tendency of digital image processing technology from the perspective of technology application.

  13. Multimodal imaging of bone metastases: From preclinical to clinical applications

    Directory of Open Access Journals (Sweden)

    Stephan Ellmann

    2015-10-01

    Full Text Available Metastases to the skeletal system are commonly observed in cancer patients, highly affecting the patients' quality of life. Imaging plays a major role in detection, follow-up, and molecular characterisation of metastatic disease. Thus, imaging techniques have been optimised and combined in a multimodal and multiparametric manner for assessment of complementary aspects in osseous metastases. This review summarises both application of the most relevant imaging techniques for bone metastasis in preclinical models and the clinical setting.

  14. Clinical Applications of Diffusion Tensor Imaging

    Directory of Open Access Journals (Sweden)

    Sona Saksena

    2008-01-01

    Full Text Available During the last decade, advances in the field of magnetic resonance imaging (MRI have led to the design of numerous innovative imaging techniques. These techniques have not only facilitated structural visualization of anatomy, but also have provided a wealth of functional information regarding biological processes. Diffusion tensor imaging (DTI is one such MRI technique that has generated tremendous amount of interest both in the clinical and laboratory fields. DTI attempts to analyze the magnitude and orientation of random microscopic motion of water molecules in brain tissue. It is based upon the phenomenon of water diffusion known as Brownian motion. This technique pro- vides details on tissue microstructure and organization well beyond the usual image resolution. With diffusion tensor MR imaging, diffusion anisotropy can be quantified and subtle white matter changes not normally seen on conventional MRI can be detected. These features have encouraged scientists to evaluate the integrity and direction of the fiber tracts in various pathological conditions using DTI. Tissue maladies studied by DTI in this review include cerebral ischemia and wallerian degeneration, epilepsy, multiple sclerosis, Alzheimer’s disease, schizophrenia, metabolic disorders, infections and brain tumors. We have only included the common clinical conditions to keep this review precise.

  15. Liver imaging. Clinical applications and future perspectives

    International Nuclear Information System (INIS)

    Primary hepatocellular carcinoma and liver metastases affect several millon people each year. The main imaging modalities to detect and assist diagnosis of primary and secondary liver tumours include MR imaging, CT, and US. The value of these techniques is further increased by the use of contrast agents which increase the sensitivity, and sometimes also the specificity, of the investigations. The relative advantages and drawbacks of the different contrast agents and imaging modalities in the detection and characterisation of liver tumours are discussed. Currently there is no consensus amongst investigators as to which is superior, due to the technical complexities and number of combinations possible within each of the different modalities. There continues to be advances in the hardware and software of imaging equipment, as well as a trend to develop new contrast agents with more organ-specificity. These include those targeting the hepatocytes, such as mangafodipir trisodium (MnDPDP, Teslascan), and those with reticuloendothelial cell specificity, such as the superparamagnetic iron oxides. These developments have the potential for making significant contributions to the diagnostic value of imaging procedures and, by reducing the number of investigations necessary to reach a final diagnosis, having a significant and beneficial impact on the pharmaco-economics of patient health care. (orig.)

  16. Terahertz Imaging for Biomedical Applications Pattern Recognition and Tomographic Reconstruction

    CERN Document Server

    Yin, Xiaoxia; Abbott, Derek

    2012-01-01

    Terahertz Imaging for Biomedical Applications: Pattern Recognition and Tomographic Reconstruction presents the necessary algorithms needed to assist screening, diagnosis, and treatment, and these algorithms will play a critical role in the accurate detection of abnormalities present in biomedical imaging. Terahertz biomedical imaging has become an area of interest due to its ability to simultaneously acquire both image and spectral information. Terahertz imaging systems are being commercialized with an increasing number of trials performed in a biomedical setting. Terahertz tomographic imaging and detection technology contributes to the ability to identify opaque objects with clear boundaries,and would be useful to both in vivo and ex vivo environments. This book also: Introduces terahertz radiation techniques and provides a number of topical examples of signal and image processing, as well as machine learning Presents the most recent developments in an emerging field, terahertz radiation Utilizes new methods...

  17. An Experiential Survey on Image Mining Tools, Techniques and Applications

    Directory of Open Access Journals (Sweden)

    C. Lakshmi Devasena,

    2011-03-01

    Full Text Available Digitization in every sector leads to the growth of digital data in a tremendous amount. Digital data are not only available in the form of text but it is also available in the form of images, audio andvideo. Decision making people in every field like business, public sector, hospital, etc. are trying to get useful and implicit information from the already existing digital data bases. Image mining is the concept used to extract implicit and useful data from images stored in the large data bases. Image mining is used in variety of fields like medical diagnosis, space research, remote sensing, agriculture, industries and even in the educational field. This paper elaborates the research works already done in image mining and also summarizes different tool developed, algorithms emerged and the applications of image mining used to extract the useful images in various fields.

  18. Neural networks: Application to medical imaging

    Science.gov (United States)

    Clarke, Laurence P.

    1994-01-01

    The research mission is the development of computer assisted diagnostic (CAD) methods for improved diagnosis of medical images including digital x-ray sensors and tomographic imaging modalities. The CAD algorithms include advanced methods for adaptive nonlinear filters for image noise suppression, hybrid wavelet methods for feature segmentation and enhancement, and high convergence neural networks for feature detection and VLSI implementation of neural networks for real time analysis. Other missions include (1) implementation of CAD methods on hospital based picture archiving computer systems (PACS) and information networks for central and remote diagnosis and (2) collaboration with defense and medical industry, NASA, and federal laboratories in the area of dual use technology conversion from defense or aerospace to medicine.

  19. Application of reinforcement learning for segmentation of transrectal ultrasound images

    Directory of Open Access Journals (Sweden)

    Tizhoosh Hamid R

    2008-04-01

    Full Text Available Abstract Background Among different medical image modalities, ultrasound imaging has a very widespread clinical use. But, due to some factors, such as poor image contrast, noise and missing or diffuse boundaries, the ultrasound images are inherently difficult to segment. An important application is estimation of the location and volume of the prostate in transrectal ultrasound (TRUS images. For this purpose, manual segmentation is a tedious and time consuming procedure. Methods We introduce a new method for the segmentation of the prostate in transrectal ultrasound images, using a reinforcement learning scheme. This algorithm is used to find the appropriate local values for sub-images and to extract the prostate. It contains an offline stage, where the reinforcement learning agent uses some images and manually segmented versions of these images to learn from. The reinforcement agent is provided with reward/punishment, determined objectively to explore/exploit the solution space. After this stage, the agent has acquired knowledge stored in the Q-matrix. The agent can then use this knowledge for new input images to extract a coarse version of the prostate. Results We have carried out experiments to segment TRUS images. The results demonstrate the potential of this approach in the field of medical image segmentation. Conclusion By using the proposed method, we can find the appropriate local values and segment the prostate. This approach can be used for segmentation tasks containing one object of interest. To improve this prototype, more investigations are needed.

  20. Locomotion of microspheres for imaging and light focusing applications

    CERN Document Server

    Krivitsky, Leonid A; Wang, Zengbo; Lukiyanchuk, Boris

    2013-01-01

    Super-resolution imaging using sub-diffraction field localization by micron sized transparent beads (microspheres) was recently demonstrated [1]. Practical applications in microscopy require control over the positioning of the microspheres. We present a simple method of positioning and controllable movement of a microsphere by using a glass micropipette. This allows sub-diffraction imaging at arbitrary points in three dimensions, as well as the ability to track moving objects. The results are relevant to a broad scope of applications, including sample inspection, and bio-imaging.

  1. Image processing and mathematical morphology fundamentals and applications

    CERN Document Server

    Shih, Frank Y

    2009-01-01

    In the development of digital multimedia, the importance and impact of image processing and mathematical morphology are well documented in areas ranging from automated vision detection and inspection to object recognition, image analysis and pattern recognition. Those working in these ever-evolving fields require a solid grasp of basic fundamentals, theory, and related applications and few books can provide the unique tools for learning contained in this text. Image Processing and Mathematical Morphology: Fundamentals and Applications is a comprehensive, wide-ranging overview of morphological

  2. Radium-228 analysis of natural waters by Cherenkov counting of Actinium-228

    Energy Technology Data Exchange (ETDEWEB)

    Aleissa, Khalid A.; Almasoud, Fahad I.; Islam, Mohammed S. [Atomic Energy Research Institute, King Abdul Aziz City for Science and Technology, P.O. Box 6086, Riyadh 11442 (Saudi Arabia); L' Annunziata, Michael F. [IAEA Expert, Montague Group, P.O. Box 5033, Oceanside, CA 92052-5033 (United States)], E-mail: mlannunziata@cox.net

    2008-12-15

    The activities of {sup 228}Ra in natural waters were determined by the Cherenkov counting of the daughter nuclide {sup 228}Ac. The radium was pre-concentrated on MnO{sub 2} and the radium purified via ion exchange and, after a 2-day period of incubation to allow for secular equilibrium between the parent-daughter {sup 228}Ra({sup 228}Ac), the daughter nuclide {sup 228}Ac was isolated by ion exchange according to the method of Nour et al. [2004. Radium-228 determination of natural waters via concentration on manganese dioxide and separation using Diphonix ion exchange resin. Appl. Radiat. Isot. 61, 1173-1178]. The Cherenkov photons produced by {sup 228}Ac were counted directly without the addition of any scintillation reagents. The optimum Cherenkov counting window, sample volume, and vial type were determined experimentally to achieve optimum Cherenkov photon detection efficiency and lowest background count rates. An optimum detection efficiency of 10.9{+-}0.1% was measured for {sup 228}Ac by Cherenkov counting with a very low Cherenkov photon background of 0.317{+-}0.013 cpm. The addition of sodium salicylate into the sample counting vial at a concentration of 0.1 g/mL yielded a more than 3-fold increase in the Cherenkov detection efficiency of {sup 228}Ac to 38%. Tests of the Cherenkov counting technique were conducted with several water standards of known activity and the results obtained compared closely with a conventional liquid scintillation counting technique. The advantages and disadvantages of Cherenkov counting compared to liquid scintillation counting methods are discussed. Advantages include much lower Cherenkov background count rates and consequently lower minimal detectable activities for {sup 228}Ra and no need for expensive environmentally unfriendly liquid scintillation cocktails. The disadvantages of the Cherenkov counting method include the need to measure {sup 228}Ac Cherenkov photon detection efficiency and optimum Cherenkov counting volume

  3. Radium-228 analysis of natural waters by Cherenkov counting of Actinium-228.

    Science.gov (United States)

    Aleissa, Khalid A; Almasoud, Fahad I; Islam, Mohammed S; L'Annunziata, Michael F

    2008-12-01

    The activities of (228)Ra in natural waters were determined by the Cherenkov counting of the daughter nuclide (228)Ac. The radium was pre-concentrated on MnO(2) and the radium purified via ion exchange and, after a 2-day period of incubation to allow for secular equilibrium between the parent-daughter (228)Ra((228)Ac), the daughter nuclide (228)Ac was isolated by ion exchange according to the method of Nour et al. [2004. Radium-228 determination of natural waters via concentration on manganese dioxide and separation using Diphonix ion exchange resin. Appl. Radiat. Isot. 61, 1173-1178]. The Cherenkov photons produced by (228)Ac were counted directly without the addition of any scintillation reagents. The optimum Cherenkov counting window, sample volume, and vial type were determined experimentally to achieve optimum Cherenkov photon detection efficiency and lowest background count rates. An optimum detection efficiency of 10.9+/-0.1% was measured for (228)Ac by Cherenkov counting with a very low Cherenkov photon background of 0.317+/-0.013cpm. The addition of sodium salicylate into the sample counting vial at a concentration of 0.1g/mL yielded a more than 3-fold increase in the Cherenkov detection efficiency of (228)Ac to 38%. Tests of the Cherenkov counting technique were conducted with several water standards of known activity and the results obtained compared closely with a conventional liquid scintillation counting technique. The advantages and disadvantages of Cherenkov counting compared to liquid scintillation counting methods are discussed. Advantages include much lower Cherenkov background count rates and consequently lower minimal detectable activities for (228)Ra and no need for expensive environmentally unfriendly liquid scintillation cocktails. The disadvantages of the Cherenkov counting method include the need to measure (228)Ac Cherenkov photon detection efficiency and optimum Cherenkov counting volume, which are not at all required when liquid

  4. Superconducting chip receivers for imaging application

    NARCIS (Netherlands)

    Shitov, SV; Koshelets, VP; Ermakov, AB; Filippenko, LV; Baryshev, AM; Luinge, W; Gao, [No Value

    1999-01-01

    Experimental details of a unique superconducting imaging array receiver are discussed. Each pixel contains an internally pumped receiver chip mounted on the back of the elliptical microwave lens. Each chip comprises a quasi-optical SIS mixer integrated with a superconducting flux-flow oscillator (FF

  5. Comparison of mouse mammary gland imaging techniques and applications: Reflectance confocal microscopy, GFP Imaging, and ultrasound

    International Nuclear Information System (INIS)

    Genetically engineered mouse models of mammary gland cancer enable the in vivo study of molecular mechanisms and signaling during development and cancer pathophysiology. However, traditional whole mount and histological imaging modalities are only applicable to non-viable tissue. We evaluated three techniques that can be quickly applied to living tissue for imaging normal and cancerous mammary gland: reflectance confocal microscopy, green fluorescent protein imaging, and ultrasound imaging. In the current study, reflectance confocal imaging offered the highest resolution and was used to optically section mammary ductal structures in the whole mammary gland. Glands remained viable in mammary gland whole organ culture when 1% acetic acid was used as a contrast agent. Our application of using green fluorescent protein expressing transgenic mice in our study allowed for whole mammary gland ductal structures imaging and enabled straightforward serial imaging of mammary gland ducts in whole organ culture to visualize the growth and differentiation process. Ultrasound imaging showed the lowest resolution. However, ultrasound was able to detect mammary preneoplastic lesions 0.2 mm in size and was used to follow cancer growth with serial imaging in living mice. In conclusion, each technique enabled serial imaging of living mammary tissue and visualization of growth and development, quickly and with minimal tissue preparation. The use of the higher resolution reflectance confocal and green fluorescent protein imaging techniques and lower resolution ultrasound were complementary

  6. Comparison of mouse mammary gland imaging techniques and applications: Reflectance confocal microscopy, GFP Imaging, and ultrasound

    Directory of Open Access Journals (Sweden)

    Cotarla Ion

    2008-01-01

    Full Text Available Abstract Background Genetically engineered mouse models of mammary gland cancer enable the in vivo study of molecular mechanisms and signaling during development and cancer pathophysiology. However, traditional whole mount and histological imaging modalities are only applicable to non-viable tissue. Methods We evaluated three techniques that can be quickly applied to living tissue for imaging normal and cancerous mammary gland: reflectance confocal microscopy, green fluorescent protein imaging, and ultrasound imaging. Results In the current study, reflectance confocal imaging offered the highest resolution and was used to optically section mammary ductal structures in the whole mammary gland. Glands remained viable in mammary gland whole organ culture when 1% acetic acid was used as a contrast agent. Our application of using green fluorescent protein expressing transgenic mice in our study allowed for whole mammary gland ductal structures imaging and enabled straightforward serial imaging of mammary gland ducts in whole organ culture to visualize the growth and differentiation process. Ultrasound imaging showed the lowest resolution. However, ultrasound was able to detect mammary preneoplastic lesions 0.2 mm in size and was used to follow cancer growth with serial imaging in living mice. Conclusion In conclusion, each technique enabled serial imaging of living mammary tissue and visualization of growth and development, quickly and with minimal tissue preparation. The use of the higher resolution reflectance confocal and green fluorescent protein imaging techniques and lower resolution ultrasound were complementary.

  7. Applications of magnetic resonance image segmentation in neurology

    Science.gov (United States)

    Heinonen, Tomi; Lahtinen, Antti J.; Dastidar, Prasun; Ryymin, Pertti; Laarne, Paeivi; Malmivuo, Jaakko; Laasonen, Erkki; Frey, Harry; Eskola, Hannu

    1999-05-01

    After the introduction of digital imagin devices in medicine computerized tissue recognition and classification have become important in research and clinical applications. Segmented data can be applied among numerous research fields including volumetric analysis of particular tissues and structures, construction of anatomical modes, 3D visualization, and multimodal visualization, hence making segmentation essential in modern image analysis. In this research project several PC based software were developed in order to segment medical images, to visualize raw and segmented images in 3D, and to produce EEG brain maps in which MR images and EEG signals were integrated. The software package was tested and validated in numerous clinical research projects in hospital environment.

  8. Image feature detectors and descriptors foundations and applications

    CERN Document Server

    Hassaballah, Mahmoud

    2016-01-01

    This book provides readers with a selection of high-quality chapters that cover both theoretical concepts and practical applications of image feature detectors and descriptors. It serves as reference for researchers and practitioners by featuring survey chapters and research contributions on image feature detectors and descriptors. Additionally, it emphasizes several keywords in both theoretical and practical aspects of image feature extraction. The keywords include acceleration of feature detection and extraction, hardware implantations, image segmentation, evolutionary algorithm, ordinal measures, as well as visual speech recognition. .

  9. Digital signal processing techniques and applications in radar image processing

    CERN Document Server

    Wang, Bu-Chin

    2008-01-01

    A self-contained approach to DSP techniques and applications in radar imagingThe processing of radar images, in general, consists of three major fields: Digital Signal Processing (DSP); antenna and radar operation; and algorithms used to process the radar images. This book brings together material from these different areas to allow readers to gain a thorough understanding of how radar images are processed.The book is divided into three main parts and covers:* DSP principles and signal characteristics in both analog and digital domains, advanced signal sampling, and

  10. Continuous-terahertz-wave molecular imaging system for biomedical applications

    Science.gov (United States)

    Zhang, Rui; Zhang, Liangliang; Wu, Tong; Wang, Ruixue; Zuo, Shasha; Wu, Dong; Zhang, Cunlin; Zhang, Jue; Fang, Jing

    2016-07-01

    Molecular imaging techniques are becoming increasingly important in biomedical research and potentially in clinical practice. We present a continuous-terahertz (THz)-wave molecular imaging system for biomedical applications, in which an infrared (IR) laser is integrated into a 0.2-THz reflection-mode continuous-THz-wave imaging system to induce surface plasmon polaritons on the nanoparticles and further improve the intensity of the reflected signal from the water around the nanoparticles. A strong and rapid increment of the reflected THz signal in the nanoparticle solution upon the IR laser irradiation is demonstrated, using either gold or silver nanoparticles. This low-cost, simple, and stable continuous-THz-wave molecular imaging system is suitable for miniaturization and practical imaging applications; in particular, it shows great promise for cancer diagnosis and nanoparticle drug-delivery monitoring.

  11. Fast sensors for time-of-flight imaging applications.

    Science.gov (United States)

    Vallance, Claire; Brouard, Mark; Lauer, Alexandra; Slater, Craig S; Halford, Edward; Winter, Benjamin; King, Simon J; Lee, Jason W L; Pooley, Daniel E; Sedgwick, Iain; Turchetta, Renato; Nomerotski, Andrei; John, Jaya John; Hill, Laura

    2014-01-14

    The development of sensors capable of detecting particles and radiation with both high time and high positional resolution is key to improving our understanding in many areas of science. Example applications of such sensors range from fundamental scattering studies of chemical reaction mechanisms through to imaging mass spectrometry of surfaces, neutron scattering studies aimed at probing the structure of materials, and time-resolved fluorescence measurements to elucidate the structure and function of biomolecules. In addition to improved throughput resulting from parallelisation of data collection - imaging of multiple different fragments in velocity-map imaging studies, for example - fast image sensors also offer a number of fundamentally new capabilities in areas such as coincidence detection. In this Perspective, we review recent developments in fast image sensor technology, provide examples of their implementation in a range of different experimental contexts, and discuss potential future developments and applications. PMID:24002354

  12. Recent applications of thermal imagers for security assessment

    Energy Technology Data Exchange (ETDEWEB)

    Bisbee, T.L.

    1997-06-01

    This paper discusses recent applications by Sandia National Laboratories of cooled and uncooled thermal infrared imagers to wide-area security assessment systems. Thermal imagers can solve many security assessment problems associated with the protection of high-value assets at military bases, secure installations, and commercial facilities. Thermal imagers can provide surveillance video from security areas or perimeters both day and night without expensive security lighting. Until fairly recently, thermal imagers required open-loop cryogenic cooling to operate. The high cost of these systems and associated maintenance requirements restricted their widespread use. However, recent developments in reliable, closed-loop, linear drive cryogenic coolers and uncooled infrared imagers have dramatically reduced maintenance requirements, extended MTBF, and are leading to reduced system cost. These technology developments are resulting in greater availability and practicality for military as well as civilian security applications.

  13. Using muon rings for the optical throughput calibration of the SST-1M prototype for the Cherenkov Telescope Array

    CERN Document Server

    Toscano, S; Bilnik, W; Błocki, J; Bogacz, L; Bulik, T; Cadoux, F; Christov, A; Curyło, M; della Volpe, D; Dyrda, M; Favre, Y; Frankowski, A; Grudnik, Ł; Grudzińska, M; Heller, M; Idźkowski, B; Jamrozy, M; Janiak, M; Kasperek, J; Lalik, K; Lyard, E; Mach, E; Mandat, D; Marszałek, A; Michałowski, J; Moderski, R; Montaruli, T; Neronov, A; Niemiec, J; Ostrowski, M; Paśko, P; Pech, M; Porcelli, A; Rameez, M; Rajda, P; Schioppa, E jr; Schovanek, P; Seweryn, K; Skowron, K; Sliusar, V; Sowiński, M; Stawarz, Ł; Stodulska, M; Stodulski, M; Pujadas, I Troyano; Walter, R; Więcek, M; Zagdański, A; Ziętara, K; Żychowski, P

    2015-01-01

    Imaging Atmospheric Cherenkov Telescopes (IACTs) are ground-based instruments devoted to the study of very high energy gamma-rays coming from space. The detection technique consists of observing images created by the Cherenkov light emitted when gamma rays, or more generally cosmic rays, propagate through the atmosphere. While in the case of protons or gamma-rays the images present a filled and more or less elongated shape, energetic muons penetrating the atmosphere are visualised as characteristic circular rings or arcs. A relatively simple analysis of the ring images allows the reconstruction of all the relevant parameters of the detected muons, such as the energy, the impact parameter, and the incoming direction, with the final aim to use them to calibrate the total optical throughput of the given IACT telescope. We present the results of preliminary studies on the use of images created by muons as optical throughput calibrators of the single mirror small size telescope prototype SST-1M proposed for the Ch...

  14. The CLEO-III Ring Imaging Cherenkov Detector

    CERN Document Server

    Mountain, R J; Artuso, M; Ayad, R; Azfar, F; Coan, T E; Efimov, A; Fadeev, V; Kopp, S E; Kubota, Y; Lipeles, E; Majumder, G; Schuh, S; Skwarnicki, T; Smith, A; Staeck, J; Stone, S; Viehhauser, G; Volobuev, I P

    1999-01-01

    The CLEO-III Detector upgrade for charged particle identification is discussed. The RICH design uses solid LiF crystal radiators coupled with multi-wire chamber photon detectors, using TEA as the photosensor, and low-noise Viking readout electronics. Results from our beam test at Fermilab are presented.

  15. Ring imaging Cherenkov detector of PHENIX experiment at RHIC

    International Nuclear Information System (INIS)

    The RICH detector of the PHENIX experiment at RHIC is currently under construction. Its main function is to identity electron tracks in a very high particle density, about 1000 charged particles per unit rapidity, expected in the most violent collisions at RHIC. The design and construction status of the detector and its expected performance are described

  16. Ring imaging Cherenkov detector of PHENIX experiment at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Akiba, Y. E-mail: akiba@bnl.gov; Begay, R.; Burward-Hoy, J.; Chappell, R.; Crook, D.; Ebisu, K.; Emery, M.S.; Ferriera, J.; Frawley, A.D.; Hamagaki, H.; Hara, H.; Hayano, R.S.; Hemmick, T.K.; Hibino, M.; Hutter, R.; Kennedy, M.; Kikuchi, J.; Matsumoto, T.; Moscone, C.G.; Nagasaka, Y.; Nishimura, S.; Oyama, K.; Sakaguchi, T.; Salomone, S.; Shigaki, K.; Tanaka, Y.; Walker, J.W.; Wintenberg, A.L.; Young, G.R

    1999-08-21

    The RICH detector of the PHENIX experiment at RHIC is currently under construction. Its main function is to identity electron tracks in a very high particle density, about 1000 charged particles per unit rapidity, expected in the most violent collisions at RHIC. The design and construction status of the detector and its expected performance are described.

  17. Ring imaging Cherenkov detector of PHENIX experiment at RHIC

    CERN Document Server

    Akiba, Y; Burward-Hoy, J; Chappell, R; Crook, D; Ebisu, K; Emery, M S; Ferriera, J; Frawley, A D; Hamagaki, H; Hara, H; Hayano, R S; Hemmick, T K; Hibino, M; Hutter, R; Kennedy, M; Kikuchi, J; Matsumoto, T; Moscone, C G; Nagasaka, Y; Nishimura, S; Oyama, K; Sakaguchi, T; Salomone, S; Shigaki, K; Tanaka, Y; Walker, J W; Wintenberg, A L; Young, G R

    1999-01-01

    The RICH detector of the PHENIX experiment at RHIC is currently under construction. Its main function is to identity electron tracks in a very high particle density, about 1000 charged particles per unit rapidity, expected in the most violent collisions at RHIC. The design and construction status of the detector and its expected performance are described.

  18. MATLAB-based Applications for Image Processing and Image Quality Assessment – Part II: Experimental Results

    Directory of Open Access Journals (Sweden)

    L. Krasula

    2012-04-01

    Full Text Available The paper provides an overview of some possible usage of the software described in the Part I. It contains the real examples of image quality improvement, distortion simulations, objective and subjective quality assessment and other ways of image processing that can be obtained by the individual applications.

  19. [The application of X-ray imaging in forensic medicine].

    Science.gov (United States)

    Kučerová, Stěpánka; Safr, Miroslav; Ublová, Michaela; Urbanová, Petra; Hejna, Petr

    2014-07-01

    X-ray is the most common, basic and essential imaging method used in forensic medicine. It serves to display and localize the foreign objects in the body and helps to detect various traumatic and pathological changes. X-ray imaging is valuable in anthropological assessment of an individual. X-ray allows non-invasive evaluation of important findings before the autopsy and thus selection of the optimal strategy for dissection. Basic indications for postmortem X-ray imaging in forensic medicine include gunshot and explosive fatalities (identification and localization of projectiles or other components of ammunition, visualization of secondary missiles), sharp force injuries (air embolism, identification of the weapon) and motor vehicle related deaths. The method is also helpful for complex injury evaluation in abused victims or in persons where abuse is suspected. Finally, X-ray imaging still remains the gold standard method for identification of unknown deceased. With time modern imaging methods, especially computed tomography and magnetic resonance imaging, are more and more applied in forensic medicine. Their application extends possibilities of the visualization the bony structures toward a more detailed imaging of soft tissues and internal organs. The application of modern imaging methods in postmortem body investigation is known as digital or virtual autopsy. At present digital postmortem imaging is considered as a bloodless alternative to the conventional autopsy.

  20. Longwave Imaging for Astronomical Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a compact portable longwave camera for astronomical applications. In Phase 1, we will develop and deliver the focal plane array (FPA) - a...

  1. Longwave Imaging for Astronomical Applications Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop a compact portable longwave camera for astronomical applications. In Phase 1, we successfully developed the eye of the camera, i.e. the focal...

  2. Mass spectrometry imaging: applications to food science.

    Science.gov (United States)

    Taira, Shu; Uematsu, Kohei; Kaneko, Daisaku; Katano, Hajime

    2014-01-01

    Two-dimensional mass spectrometry (MS) analysis of biological samples by means of what is called MS imaging (MSI) is now being used to analyze analyte distribution because it facilitates determination of the existence (what is it?) and localization (where is it?) of biomolecules. Reconstruction of mass image by target signal is given after two-dimensional MS measurements on a sample section. From only one section, we can understand the existence and localization of many molecules without the need of an antibody or fluorescent reagent. In this review, we introduce the analysis of localization of functional constituents and nutrients in herbal medicine products via MSI. The ginsenosides were mainly distributed in the periderm and the tip region of the root of Panax ginseng. The capsaicin was found to be more dominantly localized in the placenta than the pericarp and seed in Capsicum fruits. We expect MSI will be a useful technique for optical quality assurance.

  3. Bayesian image reconstruction: Application to emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Nunez, J.; Llacer, J.

    1989-02-01

    In this paper we propose a Maximum a Posteriori (MAP) method of image reconstruction in the Bayesian framework for the Poisson noise case. We use entropy to define the prior probability and likelihood to define the conditional probability. The method uses sharpness parameters which can be theoretically computed or adjusted, allowing us to obtain MAP reconstructions without the problem of the grey'' reconstructions associated with the pre Bayesian reconstructions. We have developed several ways to solve the reconstruction problem and propose a new iterative algorithm which is stable, maintains positivity and converges to feasible images faster than the Maximum Likelihood Estimate method. We have successfully applied the new method to the case of Emission Tomography, both with simulated and real data. 41 refs., 4 figs., 1 tab.

  4. Clinical application of several tumor imaging agents

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Neoplasms is one of the main diseases for harming health.It is difficult to prevent the neoplasms because the factors of bringing out them are complex.To raise survival rate the early diagnosis of tumors is very important.Radionuclide imaging is useful to detect recurrent or residual diseaseand to identificate benign or malignant tumor.Several tumorimaging agents as following have clinical significance indiagnosing tumors.

  5. Liposomes - experiment of magnetic resonance imaging application

    International Nuclear Information System (INIS)

    Most pharmaceutical research effort with liposomes has been involved with the investigation of their use as drug carriers to particular target organs. Recently there has been a growing interest in liposomes not only as carrier of drugs but as a tool for the introduction of various substances into the human body. In this study, liposome delivery of nitroxyl radicals as NMR contrast agent for improved tissue imaging is experimented in rats

  6. Proton imaging apparatus for proton therapy application

    International Nuclear Information System (INIS)

    Radiotherapy with protons, due to the physical properties of these particles, offers several advantages for cancer therapy as compared to the traditional radiotherapy and photons. In the clinical use of proton beams, a p CT (Proton Computer Tomography) apparatus can contribute to improve the accuracy of the patient positioning and dose distribution calculation. In this paper a p CT apparatus built by the Prima (Proton Imaging) Italian Collaboration will be presented and the preliminary results will be discussed.

  7. Image mathematical morphology and image restoration application in detecting underground bin level

    Institute of Scientific and Technical Information of China (English)

    SUN Ji-ping; WU Bing

    2004-01-01

    By using image recognition technology, the underground bin level can be detdcted. The bin image is noised by vibration, atomy, backgroun and so on. The image restoration and image mathematical morphology were used based on neural network.A modified Hopfield network was presented for image restoration. The greed algorithm with n-simultaneous updates and apartially asynchronous algorithm were combined, improving convergence and avoiding synchronization penalties. Mathematical morphology was widely applicated in digital image processing. The basic idea of mathematical morphology is to use construction element measure image morphology for solving understand problem. Presented advanced Cellular neural network that forms MMCNN equation to be suit for mathematical morphology filter. It gave the theory of MMCNN dynamic extent and stable state. It was evidenced that arrived mathematical morphology filter through steady of dynamic precess in definite condition. The results of implementation were applied in detecting undergroug bin level.

  8. Application of XR imaging in dentistry

    International Nuclear Information System (INIS)

    Full text: For accurate and sure diagnosis in dentistry except anamnestic information (history taking) and clinical examination as an obligatory clinical examination must attend imaging investigation. For diagnosis of diseases of the teeth are used a number of imaging methods. The most widespread of them are segmental roentgenography, ortopamtomography Bitewing, as well as increasingly coming in use dental cone-beam computed tomography (3D CBCT). The aim is to introduce the types of radiographs and their benefits for prompt and proper treatment. Documentary method - a review and analysis of literature and Internet sources are made. Results and comments: Segmented radiography gives us information about the state of the tooth as a whole. Using this method gives an opportunity to visualize the crown, the neck and the root of the tooth. Ortopantomography gives a general view of the state of the maxilla and mandibula, the teeth, part of the maxillary sinuses and temporomandibular joints. Some or extra teeth, are discovered as well as dental disease conditions, bone abnormalities, cysts and others. Bitewing is used when caries is strongly suspected, though not visually, in cases of bone loss and others. The advantage of early and accurate diagnosis is to reduce future complications. Conclusion: good prevention and early detection of dental anomalies and pathologies is performed with the help of X-ray. The selection of the correct method for imaging, the proper use of X-ray machines and placing the required security means reducing the amount of radiation exposure to the patient

  9. X-ray imaging for security applications

    Science.gov (United States)

    Evans, J. Paul

    2004-01-01

    The X-ray screening of luggage by aviation security personnel may be badly hindered by the lack of visual cues to depth in an image that has been produced by transmitted radiation. Two-dimensional "shadowgraphs" with "organic" and "metallic" objects encoded using two different colors (usually orange and blue) are still in common use. In the context of luggage screening there are no reliable cues to depth present in individual shadowgraph X-ray images. Therefore, the screener is required to convert the 'zero depth resolution' shadowgraph into a three-dimensional mental picture to be able to interpret the relative spatial relationship of the objects under inspection. Consequently, additional cognitive processing is required e.g. integration, inference and memory. However, these processes can lead to serious misinterpretations of the actual physical structure being examined. This paper describes the development of a stereoscopic imaging technique enabling the screener to utilise binocular stereopsis and kinetic depth to enhance their interpretation of the actual nature of the objects under examination. Further work has led to the development of a technique to combine parallax data (to calculate the thickness of a target material) with the results of a basis material subtraction technique to approximate the target's effective atomic number and density. This has been achieved in preliminary experiments with a novel spatially interleaved dual-energy sensor which reduces the number of scintillation elements required by 50% in comparison to conventional sensor configurations.

  10. Applications of Fuzzy Logic in Image Processing – A Brief

    Directory of Open Access Journals (Sweden)

    Mahesh Prasanna K

    2015-10-01

    Full Text Available  The subject of this study is to show the application of fuzzy logic in image processing with a brief introduction to fuzzy logic and digital image processing. Digital image processing is an ever expanding and dynamic area with applications reaching out into our everyday life such as medicine, space exploration, surveillance, authentication, automated industry inspection and many more areas. Fuzzy logic, one of the decision-making techniques of artificial intelligence, has many application areas. Although it has been subjected to criticisms since its birth, especially in recent years, fuzzy logic has been proven to be applicable in almost all scientific fields. This shows that the concept of fuzzy logic will maintain its validity and the number of fields where it draws attention will increase further.

  11. High-resolution Image Reconstruction by Neural Network and Its Application in Infrared Imaging

    Institute of Scientific and Technical Information of China (English)

    ZHANG Nan; JIN Wei-qi; SU Bing-hua

    2005-01-01

    As digital image techniques have been widely used, the requirements for high-resolution images become increasingly stringent. Traditional single-frame interpolation techniques cannot add new high frequency information to the expanded images, and cannot improve resolution in deed. Multiframe-based techniques are effective ways for high-resolution image reconstruction, but their computation complexities and the difficulties in achieving image sequences limit their applications. An original method using an artificial neural network is proposed in this paper. Using the inherent merits in neural network, we can establish the mapping between high frequency components in low-resolution images and high-resolution images. Example applications and their results demonstrated the images reconstructed by our method are aesthetically and quantitatively (using the criteria of MSE and MAE) superior to the images acquired by common methods. Even for infrared images this method can give satisfactory results with high definition. In addition, a single-layer linear neural network is used in this paper, the computational complexity is very low, and this method can be realized in real time.

  12. Multifunctional Nanoparticles for Drug Delivery Applications Imaging, Targeting, and Delivery

    CERN Document Server

    Prud'homme, Robert

    2012-01-01

    This book clearly demonstrates the progression of nanoparticle therapeutics from basic research to applications. Unlike other books covering nanoparticles used in medical applications, Multifunctional Nanoparticles for Drug Delivery Applications presents the medical challenges that can be reduced or even overcome by recent advances in nanoscale drug delivery. Each chapter highlights recent progress in the design and engineering of select multifunctional nanoparticles with topics covering targeting, imaging, delivery, diagnostics, and therapy.

  13. Parallelism and Scalability in an Image Processing Application

    DEFF Research Database (Denmark)

    Rasmussen, Morten Sleth; Stuart, Matthias Bo; Karlsson, Sven

    2009-01-01

    parallel programs. This paper investigates parallelism and scalability of an embedded image processing application. The major challenges faced when parallelizing the application were to extract enough parallelism from the application and to reduce load imbalance. The application has limited immediately......The recent trends in processor architecture show that parallel processing is moving into new areas of computing in the form of many-core desktop processors and multi-processor system-on-chips. This means that parallel processing is required in application areas that traditionally have not used...

  14. Mining remote-image repositories with application to Mars Rover stereoscopic image datasets

    Science.gov (United States)

    Willis, Andrew; Shadid, Waseem; Eppes, Martha C.

    2009-02-01

    As of December 2008, the two Mars rover spacecraft Spirit and Opportunity have collected more than 4 years worth of data from nine imaging instruments producing greater than 200k images which includes both raw image data from spacecraft instruments and images generated by post-processing algorithms developed by NASA's Multimission Image Processing Laboratory (MIPL). This paper describes a prototype software system that allows scientists to browse and data-mine the images produced from NASA's Mars Exploratory Rover (MER) missions with emphasis on the automatic detection of images containing rocks that are of interest for geological research. We highlight two aspects of our prototype system: (1) software design for mining remote data repositories, (2) a computationally efficient image search engine for detecting MER images that containing rocks. Datatype abstractions made at the software design level allow users to access and visualize the source data through a single simple-to-use interface when the underlying data may originate from a local or remote image repository. Data mining queries into the MER image data are specified over chronological intervals denoted (sols) as each interval is a solar day. As in other mining applications, an automatic detection and classification algorithm is used to compute a relevance score that represents how relevant a given recorded image is to the user-specified query. Query results are presented as list of records, sorted by their relevance score, which the user may then visualize and investigate to extract information of interest. Several standard image analysis tools are provided for investigation of 2D images (e.g., histogram equalization, edge detection, etc.) and, when available, stereoscopic data is integrated with the image data using multiple windows which show both the 2D image and 3D surface geometry. The combination of data mining and a high-quality visualization interface provides MER researchers unprecedented access

  15. An Analog Trigger System for Atmospheric Cherenkov Telescopes

    CERN Document Server

    Barcelo, M; Bigas, O Blanch; Boix, J; Delgado, C; Herranz, D; Lopez-Coto, R; Martinez, G

    2013-01-01

    Arrays of Cherenkov telescopes typically use multi-level trigger schemes to keep the rate of random triggers from the night sky background low. At a first stage, individual telescopes produce a trigger signal from the pixel information in the telescope camera. The final event trigger is then formed by combining trigger signals from several telescopes. In this poster, we present a possible scheme for the Cherenkov Telescope Array telescope trigger, which is based on the analog pulse information of the pixels in a telescope camera. Advanced versions of all components of the system have been produced and working prototypes have been tested, showing a performance that meets the original specifications. Finally, issues related to integrating the trigger system in a telescope camera and in the whole array will be dealt with.

  16. Performance test of wavelength-shifting acrylic plastic Cherenkov detector

    CERN Document Server

    Beckford, B; de la Puente, A; Fuji, Y; Futatsukawa, K; Hashimoto, O; Kaneta, M; Kanda, H; Koike, T; Maeda, K; Matsumura, A; Nakamura, S N; Okayasu, Y; Perez, N; Reinhold, J; Shirotori, K; Tamura, H; Tang, L; Tsukada, K

    2010-01-01

    The collection efficiency for Cherenkov light incident on a wavelength shifting plate (WLS) has been determined during a beam test at the Proton Synchrotron facility located in the National Laboratory for High Energy Physics (KEK), Tsukuba, Japan. The experiment was conducted in order to determine the detector's response to photoelectrons converted from photons produced by a fused silica radiator; this allows for an approximation of the detector's quality. The yield of the photoelectrons was measured as a function of the momentum of the incident hadron beam. The yield is proportional to sin2{\\theta}c, where {\\theta}c is the opening angle of the Cherenkov light created. Based on estimations and results from similarly conducted tests, where the collection efficiency was roughly 39%, the experimental result was expected to be around 40% for internally produced light from the WLS. The results of the experiment determined the photon collection response efficiency of the WLS to be roughly 62% for photons created in...

  17. G-APDs in Cherenkov astronomy: The FACT camera

    Energy Technology Data Exchange (ETDEWEB)

    Kraehenbuehl, T., E-mail: thomas.kraehenbuehl@phys.ethz.ch [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); Anderhub, H. [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); Backes, M. [Technische Universitaet Dortmund, D-44221 Dortmund (Germany); Biland, A.; Boller, A.; Braun, I. [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); Bretz, T. [Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland); Commichau, V.; Djambazov, L. [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); Dorner, D.; Farnier, C. [ISDC Data Center for Astrophysics, CH-1290 Versoix (Switzerland); Gendotti, A.; Grimm, O.; Gunten, H. von; Hildebrand, D.; Horisberger, U.; Huber, B.; Kim, K.-S. [ETH Zurich, Institute for Particle Physics, CH-8093 Zurich (Switzerland); Koehne, J.-H.; Krumm, B. [Technische Universitaet Dortmund, D-44221 Dortmund (Germany); and others

    2012-12-11

    Geiger-mode avalanche photodiodes (G-APD, SiPM) are a much discussed alternative to photomultiplier tubes in Cherenkov astronomy. The First G-APD Cherenkov Telescope (FACT) collaboration builds a camera based on a hexagonal array of 1440 G-APDs and has now finalized its construction phase. A light-collecting solid PMMA cone is glued to each G-APD to eliminate dead space between the G-APDs by increasing the active area, and to restrict the light collection angle of the sensor to the reflector area in order to reduce the amount of background light. The processing of the signals is integrated in the camera and includes the digitization using the domino ring sampling chip DRS4.

  18. A Resolution to Cherenkov-like Radiation of OPERA Neutrinos

    CERN Document Server

    Oda, Ichiro

    2011-01-01

    The OPERA collabotation has reported evidence of superluminal neutrinos with a mean energy 17.5 GeV ranging up to 50 GeV. However, the superluminal interpretation of the OPERA results has been recently refuted theoretically by Cherenkov-like radiation. We discuss a loophole of this argument from the kinematical viewpoint and find it possible to avoid the Cherenkov-like radiation of the OPERA neutrinos. The key idea of our argument is to admit the fact that the neutrinos travel faster than the observed speed of light while they do slower than the true speed of light in vacuum so strictly speaking they are not superluminal but subluminal. Moreover, we present a model where these two velocities of light can be constructed by taking account of influences from dark matters near the earth.

  19. Cherenkov loss factor of short relativistic bunches:general approach

    CERN Document Server

    Baturin, S S

    2013-01-01

    The interaction of short relativistic charged particle bunches with waveguides and other accelerator system components is a critical issue for the development of X-ray FELs (free electron lasers) and linear collider projects. Wakefield Cherenkov losses of short bunches have been studied previously for resistive wall, disk-loaded, corrugated and dielectric loaded waveguides. It was noted in various publications [1] that if the slowdown layer is thin, the Cherenkov loss factor of a short bunch does not depend on the guiding system material and is a constant for any given transverse cross section dimensions of the waveguides. In this paper, we consider a new approach to the analysis of loss factors for relativistic short bunches and formulate a general integral relation that allows calculation of the loss factor for a short relativistic bunch passing an arbitrary waveguide system. The loss factors calculated by this new method for various types of waveguides with arbitrary thickness slowdown layers, including in...

  20. Gas breakdown limits for inverse Cherenkov laser accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Y. [California Univ., Los Angeles, CA (United States). Dept. of Physics; Pogorelsky, I.V. [Brookhaven National Lab., Upton, NY (United States)

    1995-07-01

    The probability of avalanche, tunneling and multiphoton ionization induced by a CO{sub 2} laser in H{sub 2} gas has been calculated. Laser light screening by a self-induced plasma density gradient is considered as the limiting factor for upscaling a CO{sub 2} laser-driven Inverse Cherenkov Laser Accelerator beyond 650 MeV/m. However, in near-resonance inverse Cherenkov acceleration where a shorter wavelength laser is used at a wavelength near the resonance of the gas (e.g. 248nm in H{sub 2}), the formation of a plasma is not a problem because the plasma density is below the critical density. In that case, the laser beam propagates unaffected through the plasma and the acceleration gradient is not limited by gas breakdown. Gradients > 1 GeV/m are possible.

  1. Design of light concentrators for Cherenkov telescope observatories

    CERN Document Server

    Hénault, F; jocou, L; Khélifi, B; Manigot, P; Hormigos, S; Knodlseder, J; Olive, J F; Jean, P; Punch, M

    2013-01-01

    The Cherenkov Telescope Array (CTA) will be the largest cosmic gamma ray detector ever built in the world. It will be installed at two different sites in the North and South hemispheres and should be operational for about 30 years. In order to cover the desired energy range, the CTA is composed of typically 50-100 collecting telescopes of various sizes (from 6 to 24-m diameters). Most of them are equipped with a focal plane camera consisting of 1500 to 2000 Photomultipliers (PM) equipped with light concentrating optics, whose double function is to maximize the amount of Cherenkov light detected by the photo-sensors, and to block any stray light originating from the terrestrial environment. Two different optical solutions have been designed, respectively based on a Compound Parabolic Concentrator (CPC), and on a purely dioptric concentrating lens. In this communication are described the technical specifications, optical designs and performance of the different solutions envisioned for all these light concentra...

  2. A scanned beam THz imaging system for medical applications

    Science.gov (United States)

    Taylor, Zachary D.; Li, Wenzao; Suen, Jon; Tewari, Priyamvada; Bennett, David; Bajwa, Neha; Brown, Elliott; Culjat, Martin; Grundfest, Warren; Singh, Rahul

    2011-10-01

    THz medical imaging has been a topic of increased interest recently due largely to improvements in source and detector technology and the identification of suitable applications. One aspect of THz medical imaging research not often adequately addressed is pixel acquisition rate and phenomenology. The majority of active THz imaging systems use translation stages to raster scan a sample beneath a fixed THz beam. While these techniques have produced high resolution images of characterization targets and animal models they do not scale well to human imaging where clinicians are unwilling to place patients on large translation stages. This paper presents a scanned beam THz imaging system that can acquire a 1 cm2 area with 1 mm2 pixels and a per-pixel SNR of 40 dB in less than 5 seconds. The system translates a focused THz beam across a stationary target using a spinning polygonal mirror and HDPE objective lens. The illumination is centered at 525 GHz with ~ 125 GHz of response normalized bandwidth and the component layout is designed to optically co-locate the stationary source and detector ensuring normal incidence across a 50 mm × 50 mm field of view at standoff of 190 mm. Component characterization and images of a test target are presented. These results are some of the first ever reported for a short standoff, high resolution, scanned beam THz imaging system and represent an important step forward for practical integration of THz medical imaging where fast image acquisition times and stationary targets (patients) are requisite.

  3. Lateral organic photodetectors for imaging applications

    Science.gov (United States)

    Shafique, Umar; Karim, Karim S.

    2011-03-01

    Organic semiconductor detectors have always been in active research interest of researchers due to its low fabrication cost. Vertical organic detectors have been studied in the past but not much of the works have been done on lateral organic detectors. The lateral design has an advantage over the vertical design that it is easy to fabricate and can be easily integrated with the backplane TFT imager circuit. Integrating an organic photodetectors with TFT imager can improve the over all sensitivity of the imager. However the lateral design limits the fill-factor. Here in our work we propose a new bilayered lateral organic photodetectors with Copper-Phthalocyanine (CUPC) as top and Perylene- Tetracarboxylic Bis- Benzimidazole (PTCBI) as the bottom layer organic material. The bottom organic semiconductor layer work as both, charge transport layer and photon absorption layer. The top and bottom layer provides and heterojunction a potential gradient enough to separate the photo generated excitons in to electrons and holes. The incident photons are absorbed in the two layers active layers giving an exciton. These excitons see a potential barrier at the CUPC-PTCBI heterojunction and separated into holes and electrons. The separated electrons are directed by the external applied electric field and thus give a increase in photocurrent. Lateral organic photodetectors are simple to design and have low dark current. The photo-response of these photo detectors is observed approximately three orders higher in magnitude compare able to its dark response. The dual layer has an advantage of tuning the devices for different absorption wavelengths and were observed more stable comparable to vertical devices.

  4. Optical Cherenkov radiation in ultrafast cascaded second-harmonic generation

    DEFF Research Database (Denmark)

    Bache, Morten; Bang, Ole; Zhou, Binbin;

    2010-01-01

    -transform-limited ultrashort mid-IR pulses with pulse durations much shorter than the input near-IR pulse. The Cherenkov radiation for the crystal considered (β-barium borate) is found for pump wavelengths in the range λ = 0.95–1.45 μm, and is located in the regime λ = 1.5–3.5 μm. For shorter pump wavelengths, the phase...

  5. An Innovative Workspace for The Cherenkov Telescope Array

    OpenAIRE

    Costa, Alessandro; Sciacca, Eva; Becciani, Ugo; Massimino, Piero; Riggi, Simone; Sanchez, David; Vitello, Fabio

    2016-01-01

    The Cherenkov Telescope Array (CTA) is an initiative to build the next generation, ground-based gamma-ray observatories. We present a prototype workspace developed at INAF that aims at providing innovative solutions for the CTA community. The workspace leverages open source technologies providing web access to a set of tools widely used by the CTA community. Two different user interaction models, connected to an authentication and authorization infrastructure, have been implemented in this wo...

  6. Single domain wall effect on parametric processes via Cherenkov-type phase matching

    OpenAIRE

    Deng, Xuewei; Ren, Huaijin; Zheng, Yuanlin; Chen, Xianfeng

    2010-01-01

    We report on important influence of single domain wall (DW) of electrically poled ferroelectric crystal on parametric processes via Cherenkov-type phase matching. It shows that the effective nonlinear polarization is confined in DW and its phase velocity can be modulated when incident light is off domain wall's direction. These effects lead to novel Cherenkov second harmonic generation (CSHG) which has no analogue in bulk ferroelectrics. Complex DW-modulated parametric process via Cherenkov-t...

  7. Clinical application of functional magnetic resonance imaging

    CERN Document Server

    Alwatban, A Z W

    2002-01-01

    The work described in this thesis was carried out at the Magnetic Resonance Centre of the University of Nottingham during the time from May 1998 to April 2001, and is the work of the except where indicated by reference. The main source of signal changes in functional magnetic resonance imaging (fMRJ) is the fluctuation of paramagnetic deoxyhaemoglobin in the venous blood during different states of functional performance. For the work of this thesis, fMRI studies were carried out using a 3 T MR system with an echo planar imaging (EPI) pulse sequence. Hearing research utilising fMRI has been previously reported in normal subjects. Hearing fMRI is normally performed by stimulating the auditory cortex via an acoustic task presentation such as music, tone, etc. However, performing the same research on deaf subjects requires special equipment to be designed to allow direct stimulation of the auditory nerve. In this thesis, a new method of direct electrical stimulation of the auditory nerve is described that uses a ...

  8. Electronic terahertz imaging for security applications

    Science.gov (United States)

    Trontelj, J.; Sešek, A.

    2016-02-01

    A sophisticated THz system with 3D imaging and narrow band spectroscopy capability is presented in the paper. The key system components are the THz source, THz detector/mixer array, scanning optics, and the signal processing unit. The system is all electronic and is portable. A battery operation option allows several hours of autonomy. The most important parameters of the THz source are output power, illumination beam size and directivity, frequency modulation range, and maximal modulation frequency. The low phase noise is also a very important parameter. Optimization of these parameters is discussed in the paper. The THz source is all solid state, composed of a phase-locked oscillator, an amplifier, and frequency multipliers. The most important element of the THz system is its sensor, which performs both signal detection and at the same time mixing of the LO signal and received signal from the target. The sensor is antenna coupled nanobolometer fabricated in a linear array of eight pixels. The sensors are suspended in the vacuum to achieve an excellent signal-to-noise ratio. The quadratic characteristic of the nano-bolometer extends over six decades allowing a large dynamic range and very high LO signal levels. The scanning mirror integrated into the system allows imaging of 1024 to 8162 pixels in the x and y dimensions that are expanded to the third dimension with a resolution of few micrometers.

  9. Evaluation of Photo Multiplier Tube candidates for the Cherenkov Telescope Array

    Science.gov (United States)

    Mirzoyan, R.; Müller, D.; Hanabata, Y.; Hose, J.; Menzel, U.; Nakajima, D.; Takahashi, M.; Teshima, M.; Toyama, T.; Yamamoto, T.

    2016-07-01

    Photo Multiplier Tubes (PMTs) are the most wide spread detectors for fast, faint light signals. Six years ago, an improvement program for the PMT candidates for the Cherenkov Telescope Array (CTA) project was started with the companies Hamamatsu Photonics K.K. and Electron Tubes Enterprises Ltd. (ETE). For maximizing the performance of the CTA imaging cameras we need PMTs with outstanding good quantum efficiency, high photoelectron collection efficiency, short pulse width, very low afterpulse probability and transit time spread. We will report on the measurements of PMT R-12992-100 from Hamamatsu as their final product and the PMT D573KFLSA as one of the latest test versions from ETE as candidate PMTs for the CTA project.

  10. FACT -- Operation of the First G-APD Cherenkov Telescope

    CERN Document Server

    Bretz, T; Buß, J; Commichau, V; Djambazov, L; Dorner, D; Einecke, S; Eisenacher, D; Freiwald, J; Grimm, O; von Gunten, H; Haller, C; Hempfling, C; Hildebrand, D; Hughes, G; Horisberger, U; Knoetig, M L; Krähenbühl, T; Lustermann, W; Lyard, E; Mannheim, K; Meier, K; Mueller, S; Neise, D; Overkemping, A -K; Paravac, A; Pauss, F; Rhode, W; Röser, U; Stucki, J -P; Steinbring, T; Temme, F; Thaele, J; Vogler, P; Walter, R; Weitzel, Q

    2014-01-01

    Since more than two years, the First G-APD Cherenkov Telescope (FACT) is operating successfully at the Canary Island of La Palma. Apart from its purpose to serve as a monitoring facility for the brightest TeV blazars, it was built as a major step to establish solid state photon counters as detectors in Cherenkov astronomy. The camera of the First G-APD Cherenkov Telesope comprises 1440 Geiger-mode avalanche photo diodes (G-APD aka. MPPC or SiPM) for photon detection. Since properties as the gain of G-APDs depend on temperature and the applied voltage, a real-time feedback system has been developed and implemented. To correct for the change introduced by temperature, several sensors have been placed close to the photon detectors. Their read out is used to calculate a corresponding voltage offset. In addition to temperature changes, changing current introduces a voltage drop in the supporting resistor network. To correct changes in the voltage drop introduced by varying photon flux from the night-sky background...

  11. Experimental study and Monte Carlo modeling of the Cherenkov effect

    Energy Technology Data Exchange (ETDEWEB)

    Mishev, A.; Angelov, I.; Duverger, E.; Gschwind, R.; Makovicka, L. E-mail: libor.makovicka@pu-pm.univ-fcomte.fr; Stamenov, J

    2001-12-01

    Studies realised at the Institute for Nuclear Research and Nuclear Energy (INRNE) particularly in cosmic ray detection and construction of Muonic Cherenkov Telescope at the South West University 'Neofit Rilski' Blagoevgrad show the need to develop a theoretical model based on observed phenomena and to refinement of this for detection system optimisation. The Cherenkov effect was introduced in EGS4 code system. The first simulations realised in collaboration between the french and the bulgarian team were consecrated to different geometries of water tank in total reflection. An additional modeling of photons mean trajectory and the mean number of reflections in the tank were made. This simple model was compared with experimental data realised with {sup 60}Co gamma source, the telescope and the most efficient water tank. A trajectory simulation of Cherenkov photons in water tank was made. An efficiency estimation of the detector registration was calculated. The atmospheric model was introduced in EGS4 code and a comparison between CORSIKA5.62 and EGS4 codes was made.

  12. Soft x-ray generation by the Cherenkov effect

    Energy Technology Data Exchange (ETDEWEB)

    Moran, M.J.; Chang, B.

    1987-01-01

    The Cherenkov effect may be used to generate coherent soft x rays by taking advantage of the dielectric constants of materials in the neighborhood of atomic resonances. The Cherenkov effect usually is not possible for x rays because the refractive index is less than one for most x-ray frequencies. However, for narrow frequency bands near atomic resonances, the refractive index can exceed unity with values large enough to generate coherent x rays with efficiencies higher than any other electron-driven technique. The basic physics of the process is discussed and is used to make rough estimates of photon production efficiencies. An exact theoretical description of Cherenkov production in thin foils is used together with recently-measured refractive indices to calculate the emission distributions of 100 eV photons from thin silicon foils. These distributions are found to be roughly consistent with the simple estimates. In addition, unusual behavior by the distributions suggests a technique that can be used to increase dramatically the peak angular intensities.

  13. Soft x-ray generation by the Cherenkov effect

    International Nuclear Information System (INIS)

    The Cherenkov effect may be used to generate coherent soft x rays by taking advantage of the dielectric constants of materials in the neighborhood of atomic resonances. The Cherenkov effect usually is not possible for x rays because the refractive index is less than one for most x-ray frequencies. However, for narrow frequency bands near atomic resonances, the refractive index can exceed unity with values large enough to generate coherent x rays with efficiencies higher than any other electron-driven technique. The basic physics of the process is discussed and is used to make rough estimates of photon production efficiencies. An exact theoretical description of Cherenkov production in thin foils is used together with recently-measured refractive indices to calculate the emission distributions of 100 eV photons from thin silicon foils. These distributions are found to be roughly consistent with the simple estimates. In addition, unusual behavior by the distributions suggests a technique that can be used to increase dramatically the peak angular intensities. 15 refs., 10 figs

  14. Soft x-ray generation by the Cherenkov effect

    International Nuclear Information System (INIS)

    The Cherenkov effect may be used to generate coherent soft x rays by taking advantage of the dielectric constants of materials in the neighborhood of atomic resonances. The Cherenkov effect usually is not possible for x rays because the refractive index is less than one for most x-ray frequencies. However, for narrow frequency bands near atomic resonances, the refractive index can exceed unity with values large enough to generate coherent x rays with efficiencies higher than any other electron-driven technique. The basic physics of the process is discussed and is used to make rough estimates of photon production efficiencies. An exact theoretical description of Cherenkov production in thin foils is used together with recently-measured refractive indices to calculate the emission distributions of 100 eV photons from thin silicon foils. These distributions are found to be roughly consistent with the simple estimates. In addition, unusual behavior by the distributions suggests a technique that can be used to increase dramatically the peak angular intensities

  15. Soft x-ray generation by the Cherenkov effect

    Energy Technology Data Exchange (ETDEWEB)

    Moran, M.J.; Chang, B.

    1987-02-25

    The Cherenkov effect may be used to generate coherent soft x rays by taking advantage of the dielectric constants of materials in the neighborhood of atomic resonances. The Cherenkov effect usually is not possible for x rays because the refractive index is less than one for most x-ray frequencies. However, for narrow frequency bands near atomic resonances, the refractive index can exceed unity with values large enough to generate coherent x rays with efficiencies higher than any other electron-driven technique. The basic physics of the process is discussed and is used to make rough estimates of photon production efficiencies. An exact theoretical description of Cherenkov production in thin foils is used together with recently-measured refractive indices to calculate the emission distributions of 100 eV photons from thin silicon foils. These distributions are found to be roughly consistent with the simple estimates. In addition, unusual behavior by the distributions suggests a technique that can be used to increase dramatically the peak angular intensities. 15 refs., 10 figs.

  16. The application of similar image retrieval in electronic commerce.

    Science.gov (United States)

    Hu, YuPing; Yin, Hua; Han, Dezhi; Yu, Fei

    2014-01-01

    Traditional online shopping platform (OSP), which searches product information by keywords, faces three problems: indirect search mode, large search space, and inaccuracy in search results. For solving these problems, we discuss and research the application of similar image retrieval in electronic commerce. Aiming at improving the network customers' experience and providing merchants with the accuracy of advertising, we design a reasonable and extensive electronic commerce application system, which includes three subsystems: image search display subsystem, image search subsystem, and product information collecting subsystem. This system can provide seamless connection between information platform and OSP, on which consumers can automatically and directly search similar images according to the pictures from information platform. At the same time, it can be used to provide accuracy of internet marketing for enterprises. The experiment shows the efficiency of constructing the system. PMID:24883411

  17. The application of similar image retrieval in electronic commerce.

    Science.gov (United States)

    Hu, YuPing; Yin, Hua; Han, Dezhi; Yu, Fei

    2014-01-01

    Traditional online shopping platform (OSP), which searches product information by keywords, faces three problems: indirect search mode, large search space, and inaccuracy in search results. For solving these problems, we discuss and research the application of similar image retrieval in electronic commerce. Aiming at improving the network customers' experience and providing merchants with the accuracy of advertising, we design a reasonable and extensive electronic commerce application system, which includes three subsystems: image search display subsystem, image search subsystem, and product information collecting subsystem. This system can provide seamless connection between information platform and OSP, on which consumers can automatically and directly search similar images according to the pictures from information platform. At the same time, it can be used to provide accuracy of internet marketing for enterprises. The experiment shows the efficiency of constructing the system.

  18. Applications of evolutionary computation in image processing and pattern recognition

    CERN Document Server

    Cuevas, Erik; Perez-Cisneros, Marco

    2016-01-01

    This book presents the use of efficient Evolutionary Computation (EC) algorithms for solving diverse real-world image processing and pattern recognition problems. It provides an overview of the different aspects of evolutionary methods in order to enable the reader in reaching a global understanding of the field and, in conducting studies on specific evolutionary techniques that are related to applications in image processing and pattern recognition. It explains the basic ideas of the proposed applications in a way that can also be understood by readers outside of the field. Image processing and pattern recognition practitioners who are not evolutionary computation researchers will appreciate the discussed techniques beyond simple theoretical tools since they have been adapted to solve significant problems that commonly arise on such areas. On the other hand, members of the evolutionary computation community can learn the way in which image processing and pattern recognition problems can be translated into an...

  19. The Application of Similar Image Retrieval in Electronic Commerce

    Directory of Open Access Journals (Sweden)

    YuPing Hu

    2014-01-01

    Full Text Available Traditional online shopping platform (OSP, which searches product information by keywords, faces three problems: indirect search mode, large search space, and inaccuracy in search results. For solving these problems, we discuss and research the application of similar image retrieval in electronic commerce. Aiming at improving the network customers’ experience and providing merchants with the accuracy of advertising, we design a reasonable and extensive electronic commerce application system, which includes three subsystems: image search display subsystem, image search subsystem, and product information collecting subsystem. This system can provide seamless connection between information platform and OSP, on which consumers can automatically and directly search similar images according to the pictures from information platform. At the same time, it can be used to provide accuracy of internet marketing for enterprises. The experiment shows the efficiency of constructing the system.

  20. Monte Carlo studies of medium-size telescope designs for the Cherenkov Telescope Array

    Science.gov (United States)

    Wood, M.; Jogler, T.; Dumm, J.; Funk, S.

    2016-01-01

    We present studies for optimizing the next generation of ground-based imaging atmospheric Cherenkov telescopes (IACTs). Results focus on mid-sized telescopes (MSTs) for CTA, detecting very high energy gamma rays in the energy range from a few hundred GeV to a few tens of TeV. We describe a novel, flexible detector Monte Carlo package, FAST (FAst Simulation for imaging air cherenkov Telescopes), that we use to simulate different array and telescope designs. The simulation is somewhat simplified to allow for efficient exploration over a large telescope design parameter space. We investigate a wide range of telescope performance parameters including optical resolution, camera pixel size, and light collection area. In order to ensure a comparison of the arrays at their maximum sensitivity, we analyze the simulations with the most sensitive techniques used in the field, such as maximum likelihood template reconstruction and boosted decision trees for background rejection. Choosing telescope design parameters representative of the proposed Davies-Cotton (DC) and Schwarzchild-Couder (SC) MST designs, we compare the performance of the arrays by examining the gamma-ray angular resolution and differential point-source sensitivity. We further investigate the array performance under a wide range of conditions, determining the impact of the number of telescopes, telescope separation, night sky background, and geomagnetic field. We find a 30-40% improvement in the gamma-ray angular resolution at all energies when comparing arrays with an equal number of SC and DC telescopes, significantly enhancing point-source sensitivity in the MST energy range. We attribute the increase in point-source sensitivity to the improved optical point-spread function and smaller pixel size of the SC telescope design.

  1. High Throughput Multispectral Image Processing with Applications in Food Science

    OpenAIRE

    Tsakanikas, Panagiotis; Pavlidis, Dimitris; Nychas, George-John

    2015-01-01

    Recently, machine vision is gaining attention in food science as well as in food industry concerning food quality assessment and monitoring. Into the framework of implementation of Process Analytical Technology (PAT) in the food industry, image processing can be used not only in estimation and even prediction of food quality but also in detection of adulteration. Towards these applications on food science, we present here a novel methodology for automated image analysis of several kinds of fo...

  2. Cross-relaxation imaging:methods, challenges and applications

    International Nuclear Information System (INIS)

    An overview of quantitative magnetization transfer (qMT) is given, with focus on cross relaxation imaging (CRI) as a fast method for quantifying the proportion of protons bound to complex macromolecules in tissue. The procedure for generating CRI maps is outlined, showing examples in the human brain and knee, and discussing the caveats and challenges in generating precise and accurate CRI maps. Finally, several applications of CRI for imaging tissue microstructure are presented.(Author)

  3. Advances in the Application of Image Processing Fruit Grading

    OpenAIRE

    Fang, Chengjun; Hua, Chunjian

    2013-01-01

    In the perspective of actual production, the paper presents the advances in the application of image processing fruit grading from several aspects, such as processing precision and processing speed of image processing technology. Furthermore, the different algorithms about detecting size, shape, color and defects are combined effectively to reduce the complexity of each algorithm and achieve a balance between the processing precision and processing speed are keys to automatic apple grading.

  4. High resolution imaging detectors and applications

    CERN Document Server

    Saha, Swapan K

    2015-01-01

    Interferometric observations need snapshots of very high time resolution of the order of (i) frame integration of about 100 Hz or (ii) photon-recording rates of several megahertz (MHz). Detectors play a key role in astronomical observations, and since the explanation of the photoelectric effect by Albert Einstein, the technology has evolved rather fast. The present-day technology has made it possible to develop large-format complementary metal oxide–semiconductor (CMOS) and charge-coupled device (CCD) array mosaics, orthogonal transfer CCDs, electron-multiplication CCDs, electron-avalanche photodiode arrays, and quantum-well infrared (IR) photon detectors. The requirements to develop artifact-free photon shot noise-limited images are higher sensitivity and quantum efficiency, reduced noise that includes dark current, read-out and amplifier noise, smaller point-spread functions, and higher spectral bandwidth. This book aims to address such systems, technologies and design, evaluation and calibration, control...

  5. Clinical application of functional magnetic resonance imaging

    International Nuclear Information System (INIS)

    The work described in this thesis was carried out at the Magnetic Resonance Centre of the University of Nottingham during the time from May 1998 to April 2001, and is the work of the author except where indicated by reference. The main source of signal changes in functional magnetic resonance imaging (fMRJ) is the fluctuation of paramagnetic deoxyhaemoglobin in the venous blood during different states of functional performance. For the work of this thesis, fMRI studies were carried out using a 3 T MR system with an echo planar imaging (EPI) pulse sequence. Hearing research utilising fMRI has been previously reported in normal subjects. Hearing fMRI is normally performed by stimulating the auditory cortex via an acoustic task presentation such as music, tone, etc. However, performing the same research on deaf subjects requires special equipment to be designed to allow direct stimulation of the auditory nerve. In this thesis, a new method of direct electrical stimulation of the auditory nerve is described that uses a transtympanic electrode implanted onto the surface of the cochlea. This approach would however, result in electromotive forces (EMFs) being induced by the time varying magnetic field, which would lead to current flow and heating, as well as deflection of the metallic electrode within the static magnetic field, and image distortion due to the magnetic susceptibility difference. A gold-plated tungsten electrode with a zero magnetic susceptibility was developed to avoid image distortion. Used with carbon leads and a carbon reference pad, it enabled safe, distortion-free fMRI studies of deaf subjects. The study revealed activation of the primary auditory cortex. This fMRI procedure can be used to demonstrate whether the auditory pathway is fully intact, and may provide a useful method for pre-operative assessment of candidates for cochlear implantation. Glucose is the energy source on which the function of the human brain is entirely dependent. Failure to

  6. Clinical application of functional magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Alwatban, Adnan Z.W

    2002-07-01

    The work described in this thesis was carried out at the Magnetic Resonance Centre of the University of Nottingham during the time from May 1998 to April 2001, and is the work of the author except where indicated by reference. The main source of signal changes in functional magnetic resonance imaging (fMRJ) is the fluctuation of paramagnetic deoxyhaemoglobin in the venous blood during different states of functional performance. For the work of this thesis, fMRI studies were carried out using a 3 T MR system with an echo planar imaging (EPI) pulse sequence. Hearing research utilising fMRI has been previously reported in normal subjects. Hearing fMRI is normally performed by stimulating the auditory cortex via an acoustic task presentation such as music, tone, etc. However, performing the same research on deaf subjects requires special equipment to be designed to allow direct stimulation of the auditory nerve. In this thesis, a new method of direct electrical stimulation of the auditory nerve is described that uses a transtympanic electrode implanted onto the surface of the cochlea. This approach would however, result in electromotive forces (EMFs) being induced by the time varying magnetic field, which would lead to current flow and heating, as well as deflection of the metallic electrode within the static magnetic field, and image distortion due to the magnetic susceptibility difference. A gold-plated tungsten electrode with a zero magnetic susceptibility was developed to avoid image distortion. Used with carbon leads and a carbon reference pad, it enabled safe, distortion-free fMRI studies of deaf subjects. The study revealed activation of the primary auditory cortex. This fMRI procedure can be used to demonstrate whether the auditory pathway is fully intact, and may provide a useful method for pre-operative assessment of candidates for cochlear implantation. Glucose is the energy source on which the function of the human brain is entirely dependent. Failure to

  7. An imaging spectrometer for microgravity application

    Science.gov (United States)

    Wong, Wallace K.

    1995-01-01

    Flame structure is the result of complex interaction of mechanisms operating in both unwanted fires and controlled combustion systems. The scientific study of gas-jet diffusion flames in reduced-gravity environment is of interest because the effects of buoyancy on flow entrainment and acceleration are lessened. Measurements of flames have been restricted to cinematography, thermocouples, and radiometers. SSG, Inc. is developing an MWIR imaging spectrometer (MIS) for microgravity flame measurements. The device will be delivered to NASA Lewis at the end of this project to demonstrate flame measurements in the laboratory. With proper modifications, the MIS can be used to monitor a gas-jet flame under microgravity on a NASA Learjet or DC-9.

  8. All-fiber generation of 29-fs pulses at 1.3-{\\mu}m via Cherenkov radiation

    CERN Document Server

    Luo, Hao; Wang, Zhiqiang; Zhang, Liang; Feng, Cheng

    2016-01-01

    We have experimentally demonstrated the all-fiber generation of 1.3-{\\mu}m femtosecond pulses via Cherenkov radiation (CR) from an ultrafast Er-doped fiber laser. The experiment shows that the pulses maintain below 40 fs in the range from 1270 to 1315 nm with multi-milliwatt average output power. The shortest generated pulses can be as short as 29 fs. This ultrashort pulse source in 1.3-{\\mu}m window can bring the benefits to many fields such as the bio-imaging and the ultrafast spectroscopy, and so on.

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

    OpenAIRE

    Masuda, Shu; Konno, Yusuke; 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

    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...

  10. Phase Sensitive X-Ray Imaging: Towards its Interdisciplinary Applications

    Science.gov (United States)

    Kottler, C.; Revol, V.; Kaufmann, R.; Urban, C.; Knop, K.; Sennhauser, U.; Jerjen, I.; Lüthi, T.; Cardot, F.; Niedermann, P.; Morel, J.-P.; Maake, C.; Walt, H.; Knop, E.; Blanc, N.

    2010-04-01

    X-ray phase imaging including phase tomography has been attracting increasing attention during the past few decades. The advantage of X-ray phase imaging is that an extremely high sensitivity is achieved for weakly absorbing materials, such as biological soft tissues, which generate a poor contrast by conventional schemes. Especially for such living samples, where the reduction of the applied dose is of paramount interest, phase sensitive measurements schemes have an inherent potential for a significant dose reduction combined with an image quality enhancement. Several methods have been invented for x-ray phase contrast imaging that either use an approach based on interferometry, diffraction or wave-field propagation. Some of these techniques have a potential for commercial applications, such as in medicine, non-destructive testing, security and inspection. The scope of this manuscript thus deals with one particular such technique that measures the diffraction caused by the specimen by means of a grating interferometer. Examples of measurements are shown that depict the potential of phase contrast imaging for future commercial applications, such as in medical imaging, non-destructive testing and inspection for quality control. The current state of the technology is briefly reviewed as well as its shortcomings to be overcome with regard to the applications.

  11. Optical and Digital Microscopic Imaging Techniques and Applications in Pathology

    Directory of Open Access Journals (Sweden)

    Xiaodong Chen

    2011-01-01

    Full Text Available The conventional optical microscope has been the primary tool in assisting pathological examinations. The modern digital pathology combines the power of microscopy, electronic detection, and computerized analysis. It enables cellular-, molecular-, and genetic-imaging at high efficiency and accuracy to facilitate clinical screening and diagnosis. This paper first reviews the fundamental concepts of microscopic imaging and introduces the technical features and associated clinical applications of optical microscopes, electron microscopes, scanning tunnel microscopes, and fluorescence microscopes. The interface of microscopy with digital image acquisition methods is discussed. The recent developments and future perspectives of contemporary microscopic imaging techniques such as three-dimensional and in vivo imaging are analyzed for their clinical potentials.

  12. Improved Strategies for Parallel Medical Image Processing Applications

    Institute of Scientific and Technical Information of China (English)

    WANG Kun; WANG Xiao-ying; LI San-li; CHEN Ying

    2008-01-01

    In order to meet the demands of high efficient and real-time computer assisted diagnosis as well as screening in medical area, to improve the efficacy of parallel medical image processing is of great importance. This article proposes improved strategies for parallel medical image processing applications,which is categorized into two genera. For each genus individual strategy is devised, including the theoretic algorithm for minimizing the exertion time. Experiment using mammograms not only justifies the validity of the theoretic analysis, with reasonable difference between the theoretic and measured value, but also shows that when adopting the improved strategies, efficacy of medical image parallel processing is improved greatly.

  13. Imaging with electromagnetic spectrum applications in food and agriculture

    CERN Document Server

    Jayasuriya, Hemantha

    2014-01-01

    This book demonstrates how imaging techniques, applying different frequency bands from the electromagnetic spectrum, are used in scientific research. Illustrated with numerous examples this book is structured according to the different radiation bands: From Gamma-rays over UV and IR to radio frequencies. In order to ensure a clear understanding of the processing methodologies, the text is enriched with descriptions of how digital images are formed, acquired, processed and how to extract information from them. A special emphasis is given to the application of imaging techniques in food and agriculture research.

  14. Period of Arnold transformation and its application in image scrambling

    Institute of Scientific and Technical Information of China (English)

    LI Bing; XU Jia-wei

    2005-01-01

    With the security problem of image information as the background, some more properties of the period of Arnold transformation of two-dimension were studied by means of introducing a integer sequence. Some new resuits are obtained. Two interesting conjectures on the period of Arnold transformation are given. When making digital images scrambling by Arnold transformation, it is important to know the period of the transformation for the image. As the application of the theory, a new method for computing the periods at last are proposed.

  15. Motion tracking in infrared imaging for quantitative medical diagnostic applications

    Science.gov (United States)

    Cheng, Tze-Yuan; Herman, Cila

    2014-01-01

    In medical applications, infrared (IR) thermography is used to detect and examine the thermal signature of skin abnormalities by quantitatively analyzing skin temperature in steady state conditions or its evolution over time, captured in an image sequence. However, during the image acquisition period, the involuntary movements of the patient are unavoidable, and such movements will undermine the accuracy of temperature measurement for any particular location on the skin. In this study, a tracking approach using a template-based algorithm is proposed, to follow the involuntary motion of the subject in the IR image sequence. The motion tacking will allow to associate a temperature evolution to each spatial location on the body while the body moves relative to the image frame. The affine transformation model is adopted to estimate the motion parameters of the template image. The Lucas-Kanade algorithm is applied to search for the optimized parameters of the affine transformation. A weighting mask is incorporated into the algorithm to ensure its tracking robustness. To evaluate the feasibility of the tracking approach, two sets of IR image sequences with random in-plane motion were tested in our experiments. A steady-state (no heating or cooling) IR image sequence in which the skin temperature is in equilibrium with the environment was considered first. The thermal recovery IR image sequence, acquired when the skin is recovering from 60-s cooling, was the second case analyzed. By proper selection of the template image along with template update, satisfactory tracking results were obtained for both IR image sequences. The achieved tracking accuracies are promising in terms of satisfying the demands imposed by clinical applications of IR thermography.

  16. Image and signal processing for networked eHealth applications

    CERN Document Server

    Maglogiannis, Ilias

    2006-01-01

    E-health is closely related with networks and telecommunications when dealing with applications of collecting or transferring medical data from distant locations for performing remote medical collaborations and diagnosis. In this book we provide an overview of the fields of image and signal processing for networked and distributed e-health applications and their supporting technologies. The book is structured in 10 chapters, starting the discussion from the lower end, that of acquisition and processing of biosignals and medical images and ending in complex virtual reality systems and technique

  17. Comparison of Fuzzy and Neuro Fuzzy Image Fusion Techniques and its Applications

    OpenAIRE

    Rao, D. Srinivasa; Seetha, M; Prasad, M. H. M. Krishna

    2012-01-01

    Image fusion is the process of integrating multiple images of the same scene into a single fused image to reduce uncertainty and minimizing redundancy while extracting all the useful information from the source images. Image fusion process is required for different applications like medical imaging, remote sensing, medical imaging, machine vision, biometrics and military applications where quality and critical information is required. In this paper, image fusion using fuzzy and neuro fuzzy lo...

  18. Applications of the Generalized X-ray Diffraction Enhanced Imaging in the Medical Imaging

    Science.gov (United States)

    Maksimenko, Anton; Hashimoto, Eiko; Ando, Masami; Sugiyama, Hiroshi

    2007-01-01

    The X-ray Diffraction Enhanced Imaging (DEI) is the analyzer-based X-ray imaging technique which allows extraction of the "pure refraction" and "apparent absorption" contrasts from two images taken on the opposite sides of the rocking curve of the analyzing crystal. The refraction contrast obtained by this method shows many advantages over conventional absorption contrast. It was successfully applied in medicine, technique and other fields of science. However, information provided by the method is rather qualitative than quantitative. This happens because either side of the rocking curve of the analyzer is approximated as a straight line what limits the ranges of applicability and introduces additional error. One can easily overcome this problem considering the rocking curve as is instead of it's Taylor's expansion. This report is dedicated to the application of this idea in medical imaging and especially computed tomography based on the refraction contrast. The results obtained via both methods are presented and compared.

  19. High-performance imagers for space applications: The strong benefits of CMOS image sensors processes

    International Nuclear Information System (INIS)

    Space community has quickly understood the benefits that CMOS technology can procure for the design and manufacture of image sensors, with respect to CCDs which have been the detector of choice for most optical applications during the last 25 years. On the other hand, a majority of space applications is requesting high electro-optics performances to avoid payload oversizing. This was not reachable by CMOS monolithic devices built with standard mixed signal processes. Since the end of the 90s, foundries have developed outstanding CMOS processes optimised for Image Sensors. Combined with the intrinsic advantages of CMOS, they allow developing powerful imagers for space missions. After explaining specificity of CIS processes, the development of a first generation of CMOS Image Sensors for optical instrument will be detailed. Continuation of this route, thanks to the use of advanced CMOS processes, will then be presented.

  20. Application of Digital Image Correlation in Uniaxial Tensile Test

    OpenAIRE

    Aydın, Murat; Wu, Xin; Çetinkaya, Kerim; Kadı, İbrahim; Mustafa YAŞAR

    2015-01-01

    Application fields of non-contact measurement techniques have been recently increasing by means of optics and technological development in measurement applications. Digital image correlation (DIC) is the one and powerful non-contact measurement method that can be used to obtain elongation and strain as well. It is versatile and flexible measurement method can be adopted to many traditional test experiments such as tensile, compression, and bending in order to calculate mechanical properties o...

  1. Interpretation of medical imaging data with a mobile application: a mobile digital imaging processing environment

    Directory of Open Access Journals (Sweden)

    Meng Kuan eLin

    2013-07-01

    Full Text Available Digital Imaging Processing (DIP requires data extraction and output from a visualization tool to be consistent. Data handling and transmission between the server and a user is a systematic process in service interpretation. The use of integrated medical services for management and viewing of imaging data in combination with a mobile visualization tool can be greatly facilitated by data analysis and interpretation. This paper presents an integrated mobile application and digital imaging processing service, called M-DIP. The objective of the system is to (1 automate the direct data tiling, conversion, pre-tiling of brain images from Medical Imaging NetCDF (MINC, Neuroimaging Informatics Technology Initiative (NIFTI to RAW formats; (2 speed up querying of imaging measurement; and (3 display high level of images with three dimensions in real world coordinates. In addition, M-DIP provides the ability to work on a mobile or tablet device without any software installation using web-based protocols. M-DIP implements three levels of architecture with a relational middle- layer database, a stand-alone DIP server and a mobile application logic middle level realizing user interpretation for direct querying and communication. This imaging software has the ability to display biological imaging data a multiple zoom levels and to increase its quality to meet users expectations. Interpretation of bioimaging data is facilitated by an interface analogous to online mapping services using real world coordinate browsing. This allows mobile devices to display multiple datasets simultaneously from a remote site. M-DIP can be used as a measurement repository that can be accessed by any network environment, such as a portable mobile or tablet device. In addition, this system and combination with mobile applications are establishing a virtualization tool in the neuroinformatics field to speed interpretation services.

  2. Dual plasmonic gold nanoparticles for multispectral photoacoustic imaging application

    Science.gov (United States)

    Raghavan, Vijay; Subhash, Hrebesh; Breathnach, Aedán.; Leahy, Martin; Dockery, Peter; Olivo, Malini

    2014-03-01

    Nanoparticle contrast agents for molecular targeted imaging have widespread interest in diagnostic applications with cellular resolution, specificity and selectivity for visualization and assessment of various disease processes. Of particular interest is gold nanoparticle owing to its tunability of the surface plasmon resonance (SPR) and its relative inertness. Here we present the synthesis of anisotropic multi-branched star shaped gold nanoparticles exhibiting dual-band plasmon absorption peaks and its application as a contrast agent for multispectral photoacoustic imaging. The transverse plasmon absorption peak of the synthesised dual plasmonic gold nanostar (DPGNS) was around 700 nm and that of longitudinal plasmon absorption in the longer wavelength region around 1050-1150 nm. Unlike most reported PA contrast agent with surface plasmon absorption in the range of 700 to 800 nm showing moderate tissue penetration, 1050-1200 nm range lies in the farther region of the optical window of biological tissue where scattering and the intrinsic optical extinction of endogenous chromophores is at its minimum. We also present a proof of principle demonstration of DPGNS as contrast agent for multispectral photoacoustic animal imaging. Our results show that DPGNS are promising for PA imaging with extended-depth imaging applications.

  3. Sodium Magnetic Resonance Imaging: Biomedical Applications

    CERN Document Server

    Madelin, Guillaume

    2012-01-01

    In this article, we present an up-to-date overview of the potential biomedical applications of sodium MRI in vivo. Sodium MRI is a subject of increasing interest in translational research as it can give some direct and quantitative biochemical information on the tissue viability, cell integrity and function, and therefore not only help the diagnosis but also the prognosis of diseases and treatment outcomes. It has already been applied in vivo in most of human tissues, such as brain for stroke or tumor detection and therapeutic response, in breast cancer, in articular cartilage, in muscle and in kidney, and it was shown in some studies that it could provide very useful new information not available through standard proton MRI. However, this technique is still very challenging due to the low detectable sodium signal in biological tissue with MRI and hardware/software limitations of the clinical scanners. The article is divided in three parts: (1) the role of sodium in biological tissues, (2) a short review on s...

  4. Large acceptance forward Cherenkov detector for the BRAHMS experiment at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Budick, B., E-mail: bb2@nyu.ed [New York University, New York, NY 10003 (United States); Beavis, D., E-mail: beavis@bnl.go [Brookhaven National Laboratory, Upton, NY 11973 (United States); Chasman, C., E-mail: chasman@bnl.go [Brookhaven National Laboratory, Upton, NY 11973 (United States)

    2010-09-21

    A multi-element detector based on Cherenkov radiation in plastic and on photomultiplier tubes has been constructed that is particularly useful in collider experiments. The detector covers the pseudorapidity interval 3.23<{eta}<5.25 with large acceptance for the products of proton-proton and heavy ion collisions. The detector's primary purposes are determining the vertex of the interaction, providing a minimum bias trigger, finding the start time for time of flight (and other timing applications), and monitoring the luminosity. Monte Carlo simulations describe the pulse height response of the detector well, as does an analytic expression that has been developed. The detector performed well in the RHIC experiment BRAHMS.

  5. a Review of Hyperspectral Imaging in Close Range Applications

    Science.gov (United States)

    Kurz, T. H.; Buckley, S. J.

    2016-06-01

    Hyperspectral imaging is an established method for material mapping, which has been conventionally applied from airborne and spaceborne platforms for a range of applications, including mineral and vegetation mapping, change detection and environmental studies. The main advantage of lightweight hyperspectral imagers lies in the flexibility to deploy them from various platforms (terrestrial imaging and from unmanned aerial vehicles; UAVs), as well as the high spectral resolution to cover an expanding wavelength range. In addition, spatial resolution allows object sampling distances from micrometres to tens of centimetres - complementary to conventional nadir-looking systems. When this new type of imaging device was initially released, few instruments were available and the applicability and potential of the method was restricted. Today, a wider range of instruments, with a range of specifications, is available, with significant improvements over the first generation of technology. In this contribution, the state-of-the-art of hyperspectral imaging will be reviewed from a close range measurement perspective, highlighting how the method supplements geometric modelling techniques. An overview of the processing workflow, adjusted to the more complex close range imaging scenario will be given. This includes the integration with 3D laser scanning and photogrammetric models to provide a geometric framework and real world coordinate system for the hyperspectral imagery.

  6. Gene therapy imaging in patients for oncological applications

    International Nuclear Information System (INIS)

    Thus far, traditional methods for evaluating gene transfer and expression have been shown to be of limited value in the clinical arena. Consequently there is a real need to develop new methods that could be repeatedly and safely performed in patients for such purposes. Molecular imaging techniques for gene expression monitoring have been developed and successfully used in animal models, but their sensitivity and reproducibility need to be tested and validated in human studies. In this review, we present the current status of gene therapy-based anticancer strategies and show how molecular imaging, and more specifically radionuclide-based approaches, can be used in gene therapy procedures for oncological applications in humans. The basis of gene expression imaging is described and specific uses of these non-invasive procedures for gene therapy monitoring illustrated. Molecular imaging of transgene expression in humans and evaluation of response to gene-based therapeutic procedures are considered. The advantages of molecular imaging for whole-body monitoring of transgene expression as a way to permit measurement of important parameters in both target and non-target organs are also analyzed. The relevance of this technology for evaluation of the necessary vector dose and how it can be used to improve vector design are also examined. Finally, the advantages of designing a gene therapy-based clinical trial with imaging fully integrated from the very beginning are discussed and future perspectives for the development of these applications outlined. (orig.)

  7. A REVIEW OF HYPERSPECTRAL IMAGING IN CLOSE RANGE APPLICATIONS

    Directory of Open Access Journals (Sweden)

    T. H. Kurz

    2016-06-01

    Full Text Available Hyperspectral imaging is an established method for material mapping, which has been conventionally applied from airborne and spaceborne platforms for a range of applications, including mineral and vegetation mapping, change detection and environmental studies. The main advantage of lightweight hyperspectral imagers lies in the flexibility to deploy them from various platforms (terrestrial imaging and from unmanned aerial vehicles; UAVs, as well as the high spectral resolution to cover an expanding wavelength range. In addition, spatial resolution allows object sampling distances from micrometres to tens of centimetres – complementary to conventional nadir-looking systems. When this new type of imaging device was initially released, few instruments were available and the applicability and potential of the method was restricted. Today, a wider range of instruments, with a range of specifications, is available, with significant improvements over the first generation of technology. In this contribution, the state-of-the-art of hyperspectral imaging will be reviewed from a close range measurement perspective, highlighting how the method supplements geometric modelling techniques. An overview of the processing workflow, adjusted to the more complex close range imaging scenario will be given. This includes the integration with 3D laser scanning and photogrammetric models to provide a geometric framework and real world coordinate system for the hyperspectral imagery.

  8. Space station application of CCD image sensors for x-ray imaging

    International Nuclear Information System (INIS)

    Charge Coupled Device (CCD) type solid state image sensors are employed in a number of space based imaging experiments and will be the basis for a camera system to acquire x-ray diffraction images on board the Space Station. This paper will present the system engineering considerations that led to the selection of CCDs over other x-ray imaging technologies and the design of the camera system. This will include discussion of the special requirements imposed by the space environment and this x-ray crystallography mission. This systems engineering discussion will be followed by a summary of high spatial resolution CCDs that are candidates for this camera, what may become available in the future, and what improvements would make CCDs even more suited to such X-ray imaging applications on the ground as well as in space

  9. Hexabundles: imaging fiber arrays for low-light astronomical applications

    DEFF Research Database (Denmark)

    Bland-Hawthorn, Joss; Bryant, Julia; Robertson, Gordon;

    2011-01-01

    We demonstrate for the first time an imaging fibre bundle (“hexabundle”) that is suitable for low-light applications in astronomy. The most successful survey instruments at optical-infrared wavelengths today have obtained data on up to a million celestial sources using hundreds of multimode fibre...

  10. Application of digital image processing for pot plant grading.

    NARCIS (Netherlands)

    Dijkstra, J.

    1994-01-01

    The application of digital image processing for grading of pot plants has been studied. Different techniques e.q. plant part identification based on knowledge based segmentation, have been developed to measure features of plants in different growth stage. Growth experiments were performed to identif

  11. Techniques for Field Application of Lingual Ultrasound Imaging

    Science.gov (United States)

    Gick, Bryan; Bird, Sonya; Wilson, Ian

    2005-01-01

    Techniques are discussed for using ultrasound for lingual imaging in field-related applications. The greatest challenges we have faced distinguishing the field setting from the laboratory setting are the lack of controlled head/transducer movement, and the related issue of tissue compression. Two experiments are reported. First, a pilot study…

  12. Optimal Phase Masks for High Contrast Imaging Applications

    Science.gov (United States)

    Ruane, Garreth J.

    Phase-only optical elements can provide a number of important functions for high-contrast imaging. This thesis presents analytical and numerical optical design methods for accomplishing specific tasks, the most significant of which is the precise suppression of light from a distant point source. Instruments designed for this purpose are known as coronagraphs. Here, advanced coronagraph designs are presented that offer improved theoretical performance in comparison to the current state-of-the-art. Applications of these systems include the direct imaging and characterization of exoplanets and circumstellar disks with high sensitivity. Several new coronagraph designs are introduced and, in some cases, experimental support is provided. In addition, two novel high-contrast imaging applications are discussed: the measurement of sub-resolution information using coronagraphic optics and the protection of sensors from laser damage. The former is based on experimental measurements of the sensitivity of a coronagraph to source displacement. The latter discussion presents the current state of ongoing theoretical work. Beyond the mentioned applications, the main outcome of this thesis is a generalized theory for the design of optical systems with one of more phase masks that provide precise control of radiation over a large dynamic range, which is relevant in various high-contrast imaging scenarios. The optimal phase masks depend on the necessary tasks, the maximum number of optics, and application specific performance measures. The challenges and future prospects of this work are discussed in detail.

  13. Application of an image processing software for quantitative autoradiography

    International Nuclear Information System (INIS)

    The present communication deals with the utilization of an image processing device for quantitative whole-body autoradiography, cell counting and also for interpretation of chromatograms. It is shown that the system parameters allow an adequate and precise determination of optical density values. Also shown are the main error sources limiting the applicability of the system. (orig.)

  14. Perspectives on Imaging: Advanced Applications. Introduction and Overview.

    Science.gov (United States)

    Lynch, Clifford A.; Lunin, Lois F.

    1991-01-01

    Provides an overview of six articles that address relationships between electronic imaging technology and information science. Articles discuss the areas of technology; applications in the fields of visual arts, medicine, and textile history; conceptual foundations; and future visions, including work in virtual reality and cyberspace. (LRW)

  15. Hexabundles: imaging fibre arrays for low-light astronomical applications

    DEFF Research Database (Denmark)

    Bland-Hawthorn, Joss; Bryant, Julie; Robertson, Gordon;

    2010-01-01

    We demonstrate for the first time an imaging fibre bundle (“hexabundle”) that is suitable for low-light applications in astronomy. The most successful survey instruments at optical-infrared wavelengths today have obtained data on up to a million celestial sources using hundreds of multimode fibre...

  16. Application of Particle Image Velocimetry Technology in Water Tunnel

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A display and analysis system for hermetical flow field in water tunnel is developed based on the particle image velocimetry(PIV) technology. It consists of some subsystems, such as lamp-house, imaging, image processing and analyzing, control and particles putting. Taking the flow fields around a sphere and a cylinder model as an example under higher Renolds number 5.8 × 105 in water tunnel, we inquired into the application of the system to water tunnel experiment by cross correlation algorithm. The measure error is less than 2 %. The test results show that the developed system can measure and display the flow field accurately in complex flow field without touching and disturbing. The research work indicates that PIV has lots of potential applications in the underwater flow field measurement.

  17. Applications of nuclear magnetic resonance imaging in process engineering

    Science.gov (United States)

    Gladden, Lynn F.; Alexander, Paul

    1996-03-01

    During the past decade, the application of nuclear magnetic resonance (NMR) imaging techniques to problems of relevance to the process industries has been identified. The particular strengths of NMR techniques are their ability to distinguish between different chemical species and to yield information simultaneously on the structure, concentration distribution and flow processes occurring within a given process unit. In this paper, examples of specific applications in the areas of materials and food processing, transport in reactors and two-phase flow are discussed. One specific study, that of the internal structure of a packed column, is considered in detail. This example is reported to illustrate the extent of new, quantitative information of generic importance to many processing operations that can be obtained using NMR imaging in combination with image analysis.

  18. Application of optical correlation techniques to particle imaging velocimetry

    Science.gov (United States)

    Wernet, Mark P.; Edwards, Robert V.

    1988-01-01

    Pulsed laser sheet velocimetry yields nonintrusive measurements of velocity vectors across an extended 2-dimensional region of the flow field. The application of optical correlation techniques to the analysis of multiple exposure laser light sheet photographs can reduce and/or simplify the data reduction time and hardware. Here, Matched Spatial Filters (MSF) are used in a pattern recognition system. Usually MSFs are used to identify the assembly line parts. In this application, the MSFs are used to identify the iso-velocity vector contours in the flow. The patterns to be recognized are the recorded particle images in a pulsed laser light sheet photograph. Measurement of the direction of the partical image displacements between exposures yields the velocity vector. The particle image exposure sequence is designed such that the velocity vector direction is determined unambiguously. A global analysis technique is used in comparison to the more common particle tracking algorithms and Young's fringe analysis technique.

  19. Application of optical correlation techniques to particle imaging

    Science.gov (United States)

    Wernet, Mark P.; Edwards, Robert V.

    1988-01-01

    Pulsed laser sheet velocimetry yields noninstrusive measurements of velocity vectors across an extended 2-dimensional region of the flow field. The application of optical correlation techniques to the analysis of multiple exposure laser light sheet photographs can reduce and/or simplify the data reduction time and hardware. Here, Matched Spatial Filters (MSF) are used in a pattern recognition system. Usuallay MSFs are used to identify the assembly line parts. In this application, the MSFs are used to identify the iso-velocity vector contours in the flow. The patterns to be recognized are the recorded particle images in a pulsed laser light sheet photograph. Measurement of the direction of the particle image displacements between exposures yields the velocity vector. The particle image exposure sequence is designed such that the velocity vector direction is determined unambiguously. A global analysis technique is used in comparison to the more common particle tracking algorithms and Young's fringe analysis technique.

  20. Hierarchical Bayesian sparse image reconstruction with application to MRFM

    CERN Document Server

    Dobigeon, Nicolas; Tourneret, Jean-Yves

    2008-01-01

    This paper presents a hierarchical Bayesian model to reconstruct sparse images when the observations are obtained from linear transformations and corrupted by an additive white Gaussian noise. Our hierarchical Bayes model is well suited to such naturally sparse image applications as it seamlessly accounts for properties such as sparsity and positivity of the image via appropriate Bayes priors. We propose a prior that is based on a weighted mixture of a positive exponential distribution and a mass at zero. The prior has hyperparameters that are tuned automatically by marginalization over the hierarchical Bayesian model. To overcome the complexity of the posterior distribution, a Gibbs sampling strategy is proposed. The Gibbs samples can be used to estimate the image to be recovered, e.g. by maximizing the estimated posterior distribution. In our fully Bayesian approach the posteriors of all the parameters are available. Thus our algorithm provides more information than other previously proposed sparse reconstr...

  1. Magnetic resonance imaging for prostate cancer clinical application

    Institute of Scientific and Technical Information of China (English)

    Bing Li; Yong Du; Hanfeng Yang; Yayong Huang; Jun Meng; Dongmei Xiao

    2013-01-01

    As prostate cancer is a biologically heterogeneous disease for which a variety of treatment options are available,the major objective of prostate cancer imaging is to achieve more precise disease characterization.In clinical practice,magnetic resonance imaging (MRI) is one of the imaging tools for the evaluation of prostate cancer,the fusion of MRI or dynamic contrast-enhanced MRI (DCE-MRI) with magnetic resonance spectroscopic imaging (MRSI) is improving the evaluation of cancer location,size,and extent,while providing an indication of tumor aggressiveness.This review summarizes the role of MRI in the application of prostate cancer and describes molecular MRI techniques (including MRSI and DCE-MRI)for aiding prostate cancer management.

  2. PET imaging in pediatric neuroradiology: current and future applications

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sunhee [Children' s Hospital of Pittsburgh of UPMC, Department of Radiology, Pittsburgh, PA (United States); Salamon, Noriko [UCLA David Geffen School of Medicine at UCLA, Department of Radiology, Ronald Reagan UCLA Medical Center, Los Angeles, CA (United States); Jackson, Hollie A.; Blueml, Stefan [Keck School of Medicine of USC, Department of Radiology, Childrens Hospital Los Angeles, Los Angeles, CA (United States); Panigrahy, Ashok [Children' s Hospital of Pittsburgh of UPMC, Department of Radiology, Pittsburgh, PA (United States); Keck School of Medicine of USC, Department of Radiology, Childrens Hospital Los Angeles, Los Angeles, CA (United States)

    2010-01-15

    Molecular imaging with positron emitting tomography (PET) is widely accepted as an essential part of the diagnosis and evaluation of neoplastic and non-neoplastic disease processes. PET has expanded its role from the research domain into clinical application for oncology, cardiology and neuropsychiatry. More recently, PET is being used as a clinical molecular imaging tool in pediatric neuroimaging. PET is considered an accurate and noninvasive method to study brain activity and to understand pediatric neurological disease processes. In this review, specific examples of the clinical use of PET are given with respect to pediatric neuroimaging. The current use of co-registration of PET with MR imaging is exemplified in regard to pediatric epilepsy. The current use of PET/CT in the evaluation of head and neck lymphoma and pediatric brain tumors is also reviewed. Emerging technologies including PET/MRI and neuroreceptor imaging are discussed. (orig.)

  3. Hardware Software co-simulation for Image Processing Applications

    Directory of Open Access Journals (Sweden)

    A.C.Suthar

    2012-03-01

    Full Text Available We proposed the concept of hardware software co-simulation for image processing using Xilinx system generator. Recent advances in synthesis tools for SIMULINK suggest a feasible high-level approach to algorithm implementation for embedded DSP systems. An efficient FPGA based hardware design for enhancement of color and grey scale images in image and video processing. The top model - based visual development process of SIMULINK facilitates host side simulation and validation, as well as synthesis of target specific code, furthermore, legacy code written in MATLAB or ANCI C can be reuse in custom blocks. However, the code generated for DSP platforms is often not very efficient. We are implemented the Image processing applications on FPGA it can be easily design

  4. Image Segmentation Analysis for NASA Earth Science Applications

    Science.gov (United States)

    Tilton, James C.

    2010-01-01

    NASA collects large volumes of imagery data from satellite-based Earth remote sensing sensors. Nearly all of the computerized image analysis of this data is performed pixel-by-pixel, in which an algorithm is applied directly to individual image pixels. While this analysis approach is satisfactory in many cases, it is usually not fully effective in extracting the full information content from the high spatial resolution image data that s now becoming increasingly available from these sensors. The field of object-based image analysis (OBIA) has arisen in recent years to address the need to move beyond pixel-based analysis. The Recursive Hierarchical Segmentation (RHSEG) software developed by the author is being used to facilitate moving from pixel-based image analysis to OBIA. The key unique aspect of RHSEG is that it tightly intertwines region growing segmentation, which produces spatially connected region objects, with region object classification, which groups sets of region objects together into region classes. No other practical, operational image segmentation approach has this tight integration of region growing object finding with region classification This integration is made possible by the recursive, divide-and-conquer implementation utilized by RHSEG, in which the input image data is recursively subdivided until the image data sections are small enough to successfully mitigat the combinatorial explosion caused by the need to compute the dissimilarity between each pair of image pixels. RHSEG's tight integration of region growing object finding and region classification is what enables the high spatial fidelity of the image segmentations produced by RHSEG. This presentation will provide an overview of the RHSEG algorithm and describe how it is currently being used to support OBIA or Earth Science applications such as snow/ice mapping and finding archaeological sites from remotely sensed data.

  5. Applications of terahertz (THz) technology to medical imaging

    Science.gov (United States)

    Arnone, Donald D.; Ciesla, Craig M.; Corchia, Alessandra; Egusa, S.; Pepper, Michael; Chamberlain, J. Martyn; Bezant, C.; Linfield, Edmund H.; Clothier, R.; Khammo, N.

    1999-09-01

    An imaging system has been developed based on pulses of Terahertz (THz) radiation generated and detected using all- optical effects accessed by irradiating semiconductors with ultrafast pulses of visible laser light. This technique, commonly referred to as T-Ray Imaging or THz Pulse Imaging (TPI), holds enormous promise for certain aspects of medical imaging. We have conducted an initial survey of possible medical applications of TPI and demonstrated that TPI images show good contrast between different animal tissue types. Moreover, the diagnostic power of TPI has been elicidated by the spectra available at each pixel in the image, which are markedly different for the different tissue types. This suggests that the spectral information inherent in TPI might be used to identify the type of soft and hard tissue at each pixel in an image and provide other diagnostic information not afforded by conventional imagin techniques. Preliminary TPI studies of pork skin show that 3D tomographic imaging of the skin surface and thickness is possible, and data from experiments on models of the human dermis are presented which demonstrate that different constituents of skin have different refractive indices. Lastly, we present the first THz image of human tissue, namely an extracted tooth. The time of flight of THz pulses through the tooth allows the thickness of the enamel to be determined, and is used to create an image showing the enamel and dentine regions. Absorption of THz pulses in the tooth allows the pulp cavity region to be identified. Initial evidence strongly suggests that TPI my be used to provide valuable diagnostic information pertaining to the enamel, dentine, and the pump cavity.

  6. Intrinsic fluorescence of selenium nanoparticles for cellular imaging applications

    Science.gov (United States)

    Khalid, A.; Tran, Phong A.; Norello, Romina; Simpson, David A.; O'Connor, Andrea J.; Tomljenovic-Hanic, Snjezana

    2016-02-01

    Nanoparticles hold great potential in contributing to high-resolution bioimaging as well as for biomedical applications. Although, selenium (Se) nanoparticles (NPs) have been investigated owing to their potential roles in therapeutics, the imaging capability of these NPs has never been explored. This manuscript identifies the intrinsic fluorescence of Se NPs, which is highly beneficial for nanoscale imaging of biological structures. The emission of individual NPs and its evolution with time is explored. The photoluminescence spectra has revealed visible to near infrared emission for Se NPs. The work finally reflects on the role of this intrinsic fluorescence for in vitro imaging and tracking in fibroblast cells, without the need of any additional tags. This technique would overcome the limitations of the conventionally used methods of imaging with tagged fluorescent proteins and dyes, preventing possible adverse cellular effects or phototoxicity caused by the added fluorescent moieties.Nanoparticles hold great potential in contributing to high-resolution bioimaging as well as for biomedical applications. Although, selenium (Se) nanoparticles (NPs) have been investigated owing to their potential roles in therapeutics, the imaging capability of these NPs has never been explored. This manuscript identifies the intrinsic fluorescence of Se NPs, which is highly beneficial for nanoscale imaging of biological structures. The emission of individual NPs and its evolution with time is explored. The photoluminescence spectra has revealed visible to near infrared emission for Se NPs. The work finally reflects on the role of this intrinsic fluorescence for in vitro imaging and tracking in fibroblast cells, without the need of any additional tags. This technique would overcome the limitations of the conventionally used methods of imaging with tagged fluorescent proteins and dyes, preventing possible adverse cellular effects or phototoxicity caused by the added fluorescent

  7. Wideband Fractal Antennas for Holographic Imaging and Rectenna Applications

    Energy Technology Data Exchange (ETDEWEB)

    Bunch, Kyle J.; McMakin, Douglas L.; Sheen, David M.

    2008-04-18

    At Pacific Northwest National Laboratory, wideband antenna arrays have been successfully used to reconstruct three-dimensional images at microwave and millimeter-wave frequencies. Applications of this technology have included portal monitoring, through-wall imaging, and weapons detection. Fractal antennas have been shown to have wideband characteristics due to their self-similar nature (that is, their geometry is replicated at different scales). They further have advantages in providing good characteristics in a compact configuration. We discuss the application of fractal antennas for holographic imaging. Simulation results will be presented. Rectennas are a specific class of antennas in which a received signal drives a nonlinear junction and is retransmitted at either a harmonic frequency or a demodulated frequency. Applications include tagging and tracking objects with a uniquely-responding antenna. It is of interest to consider fractal rectenna because the self-similarity of fractal antennas tends to make them have similar resonance behavior at multiples of the primary resonance. Thus, fractal antennas can be suited for applications in which a signal is reradiated at a harmonic frequency. Simulations will be discussed with this application in mind.

  8. Novel Applications of Laser Doppler Vibration Measurements to Medical Imaging

    Science.gov (United States)

    Tabatabai, Habib; Oliver, David E.; Rohrbaugh, John W.; Papadopoulos, Christopher

    2013-06-01

    Laser Doppler Vibrometry (LDV) has been widely used in engineering applications involving non-contact vibration and sound measurements. This technique has also been used in some biomedical applications including hearing research. The detectable frequencies are in the range of near-DC to 1 GHz or higher. This paper reviews applications of LDV in biomedical engineering and proposes new medical imaging applications based on measuring surface vibrations of tissues and organs. Tests were conducted on human skin using single point and scanning laser vibrometers. These tests suggest that skin vibrations due to the forcing excitation from the heart can be used in imaging of blood flow. The results of these tests illustrate the potential of such vibration measurements in a variety of diagnostic medical imaging applications including blood flow/restrictions, real-time monitoring of blood pressure variations, wound healing, muscle movements, etc. The fact that the measurements can be conducted remotely (non-contact) is an important benefit that adds to the promise of this approach.

  9. Improvement of Image Matching by using the Proximity Criterion: Application to Omnidirectional and Perspective Images

    Directory of Open Access Journals (Sweden)

    Ibrahim Guelzim

    2011-01-01

    Full Text Available Problem statement: In computer vision, matching is an important phase for several applications (object reconstruction, robot navigation .... The similarity measures used provided results which could be improved. Approach: This research proposed to improve image matching by using the proximity criterion. The similarity measures used mutual information and correlation coefficient. The matching was done between neighborhoods of points of interest extracted from the images. The second chance algorithm was also applied. We have worked in case which the sensor had a slight displacement between two images. The tests were performed on omnidirectional and perspective grayscale images. Results: The improvement by introducing the proximity criterion reached 15.9% for non-noised perspective images, 32.1% for noised perspective images, 47.69% for non-noised omnidirectional images and 58.5% for noised omnidirectional images. Conclusion/Recommendations: The introduction of the proximity criterion has significantly improved the performance of the matching. The method is recommended in mobile robotics, knowing that a good matching leads to a better location and better movement of the robot.

  10. The Cherenkov Surface Detector of the Pierre Auger Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Billoir, Pierre, E-mail: billoir@lpnhe.in2p3.fr [LPNHE, CNRS/IN2P3 and Univ. P. and M. Curie and Univ. D. Diderot, 4 place Jussieu 75272 Paris Cedex 05 (France); Observatorio Pierre Auger, av. San Martín Norte, 304 5613, Malargüe (Argentina)

    2014-12-01

    The Pierre Auger Observatory detects the atmospheric showers induced by cosmic rays of ultra-high energy (UHE). It is the first one to use the hybrid technique. A set of telescopes observes the fluorescence of the nitrogen molecules on clear moonless nights, giving access to the longitudinal profile of the shower. These telescopes surround a giant array of 1600 water Cherenkov tanks (covering more than 3000 km{sup 2}), which works continuously and samples the particles reaching the ground (mainly muons, photons and electrons/positrons); the light produced within the water is recorded into FADC (Fast Analog to Digital Convertes) traces. A subsample of hybrid events provides a cross calibration of the two components. We describe the structure of the Cherenkov detectors, their sensitivity to different particles and the information they can give on the direction of origin, the energy and the nature of the primary UHE object; we discuss also their discrimination power for rare events (UHE photons or neutrinos). To cope with the variability of weather conditions and the limitations of the communication system, the procedures for trigger and real time calibration have been shared between local processors and a central acquisition system. The overall system has been working almost continuously for 10 years, while being progressively completed and increased by the creation of a dense “infill” subarray. - Highlights: • The water Cherenkov technique is used in the Surface Detector of the Pierre Auger Observatory. • Cross-calibrated with the Fluorescence Detector, it provides a measurement of the primary energy. • The spectrum of the UHE cosmic rays exhibits clearly an “ankle” and a cutoff. • The muon observed muon content of the atmospheric showers is larger than expected from the models. • Stringent limits on the flux of UHE neutrinos and photons are obtained.

  11. Study of Cherenkov Light Lateral Distribution Function around the Knee Region in Extensive Air Showers

    CERN Document Server

    Al-Rubaiee, A A; M., Marwah; Al-Douri, Y

    2015-01-01

    The Cherenkov light lateral distribution function (LDF) was simulated with the CORSIKA code, in the energy range (10^13-10^16) eV. This simulation was performed for conditions and configurations of the Tunka EAS Cherenkov array for two primary particles (p and Fe). Basing on the simulated results, many approximated functions are structured for two primary particles and different zenith angles. This allowed us to reconstruct the EAS events, which is, to determine the type and energy of the primary particles that produced showers from signal amplitudes of Cherenkov radiation which measured with Tunka Cherenkov array experiment. Comparison of the calculated LDF of Cherenkov radiation with that measured at the Tunka EAS array shows the ability for identifying of the primary particle that initiated the EAS cascades determining of its primary energy around the knee region of the cosmic ray spectrum.

  12. Imaging retinal ganglion cells: enabling experimental technology for clinical application.

    Science.gov (United States)

    Smith, Corey A; Chauhan, Balwantray C

    2015-01-01

    Recent advances in clinical ophthalmic imaging have enhanced patient care. However, the ability to differentiate retinal neurons, such as retinal ganglion cells (RGCs), would advance many areas within ophthalmology, including the screening and monitoring of glaucoma and other optic neuropathies. Imaging at the single cell level would take diagnostics to the next level. Experimental methods have provided techniques and insight into imaging RGCs, however no method has yet to be translated to clinical application. This review provides an overview of the importance of non-invasive imaging of RGCs and the clinically relevant capabilities. In addition, we report on experimental data from wild-type mice that received an in vivo intravitreal injection of a neuronal tracer that labelled RGCs, which in turn were monitored for up to 100 days post-injection with confocal scanning laser ophthalmoscopy. We were able to demonstrate efficient and consistent RGC labelling with this delivery method and discuss the issue of cell specificity. This type of experimental work is important in progressing towards clinically applicable methods for monitoring loss of RGCs in glaucoma and other optic neuropathies. We discuss the challenges to translating these findings to clinical application and how this method of tracking RGCs in vivo could provide valuable structural and functional information to clinicians. PMID:25448921

  13. MEMPHYS: A large scale water Cherenkov detector at Frejus

    Energy Technology Data Exchange (ETDEWEB)

    Bellefon, A. de; Dolbeau, J.; Gorodetzky, P.; Katsanevas, S.; Patzak, T.; Salin, P.; Tonazzo, A. [APC Paris, Paris (France); Bouchez, J. [APC Paris, Paris (France)]|[DAPNIA-CEA Saclay (France); Busto, J. [CPP Marseille (France); Campagne, J.E. [LAL Orsay (France); Cavata, C.; Mosca, L. [DAPNIA-CEA Saclay (France); Dumarchez, J. [LPNHE Paris (France); Mezzetto, M. [INFN Padova (Italy); Volpe, C. [IPN Orsay (France)

    2006-07-15

    A water Cherenkov detector project, of megaton scale, to be installed in the Frejus underground site and dedicated to nucleon decay, neutrinos from supernovae, solar and atmospheric neutrinos, as well as neutrinos from a super-beam and/or a beta-beam coming from CERN, is presented and compared with competitor projects in Japan and in the USA. The performances of the European project are discussed, including the possibility to measure the mixing angle {theta}{sub 13} and the CP-violating phase {delta}. (authors)

  14. Measurements and simulations of Cherenkov light in lead fluoride crystals

    OpenAIRE

    P. Achenbach(Mainz U., Inst. Phys); Baunack, S.; Grimm, K.; Hammel, T.; von Harrach, D.,; Ginja, A. Lopes; Maas, F. E.; Schilling, E.; Stroeher, H.

    2001-01-01

    The anticipated use of more than one thousand lead fluoride (PbF2) crystals as a fast and compact Cherenkov calorimeter material in a parity violation experiment at MAMI stimulated the investigation of the light yield (L.Y.) of these crystals. The number of photoelectrons (p.e.) per MeV deposited energy has been determined with a hybrid photomultiplier tube (HPMT). In response to radioactive sources a L.Y. between 1.7 and 1.9 p.e./MeV was measured with 4% statistical and 5% systematic error. ...

  15. Nonlinear Cherenkov difference-frequency generation exploiting birefringence of KTP

    International Nuclear Information System (INIS)

    In this letter, we demonstrate the realization of nonlinear Cherenkov difference-frequency generation (CDFG) exploiting the birefringence property of KTiOPO4 (KTP) crystal. The pump and signal waves were set to be along different polarizations, thus the phase-matching requirement of CDFG, which is, the refractive index of the pump wave should be smaller than that of the signal wave, was fulfilled. The radiation angles and the intensity dependence of the CDFG on the pump wave were measured, which agreed well with the theoretical ones

  16. Towards a network of atmospheric Cherenkov detectors 7

    Energy Technology Data Exchange (ETDEWEB)

    Robin, M. [Ecole Polytechnique, 91 - Palaiseau (France); Weekes, T.C. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Mori, M. [Tokyo Univ., Institute for Cosmic Ray Research (Japan); Mariotti, M. [Padova Univ., INFN (Italy); Hofmann, W.; Aharonian, F. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Sinitsyna, V. [P.N. Lebedev Physical Institute, Moscow (Russian Federation); Smith, D. [Centre d' Etudes Nucleaires de Bordeaux Gradignan, 33 - Gradignan (France); Marleau, P. [California Univ., Davis, CA (United States); Sinnis, G. [Los Alamos National Lab., NM (United States); Volk, H. [Max-Planck-Institut fur Kernphysik (Germany); Jager, O. de [South Africa Univ., North-West (South Africa); Harding, A. [NASA Goddard Space Flight Center (United States); Coppi, P. [Yale Univ., New Haven, CT (United States); Dermer, C. [Naval Research Laboratory (United States); Goldwurm, A.; Paul, J. [CEA Saclay, Dept. d' Astrophysique, de Physique des Particules de Physique Nucleaire et de l' Instrumentation Associee, 91- Gif sur Yvette (France); Puhlhofer, G. [Landessternwarte Heidelberg (Germany); Bernardini, E. [DESy-Zeuthen (Germany); Swordy, S. [Chicago Univ., IL (United States); Yoshikoshi, T. [Tokyo Univ., Tanashi (Japan). Inst. for Cosmic Ray Research; Teshima, M. [Max-Planck-Institute for Physics, Munich (Germany); Punch, M. [Astrophysique et Cosmologie (APC), College de France, 75 - Paris (France)

    2005-07-01

    This document gathers the papers and transparencies presented at the conference. The main part of the conference was organized into 6 sessions: 1) the review of present experiments (Veritas, Cangaroo-3, Magic, Hess-1, Shalon, Cactus, Cygnus-X-3...), 2) calibration and analysis techniques in VHE (very high energy) astrophysics, 3) multi-wavelength observations and phenomenology of sources, 4) the future of ground-based VHE astronomy, 5) developments in instrumentation for Cherenkov telescopes, and 6) the evolution of the field and its link with mainstream astrophysics.

  17. CELESTE an atmospheric Cherenkov telescope for high energy gamma astrophysics

    CERN Document Server

    Paré, E; Bazer-Bachi, R; Bergeret, H; Berny, F; Briand, N; Bruel, P; Cerutti, M; Collon, J; Cordier, A; Cornebise, P; Debiais, G; Dezalay, J P; Dumora, D; Durand, E; Eschstruth, P T; Espigat, P; Fabre, B; Fleury, P; Gilly, J; Gouillaud, J C; Gregory, C; Herault, N; Holder, J; Hrabovsky, M; Incerti, S; Jouenne, A; Kalt, L; Legallou, R; Lott, B; Lodygensky, O; Manigot, P; Manseri, H; Manitaz, H; Martin, M; Morano, R; Morineaud, G; Muenz, F; Musquere, A; Naurois, M D; Neveu, J; Noppe, J M; Olive, J F; Palatka, M; Pérez, A; Quebert, J; Rebii, A; Reposeur, T; Rob, L; Roy, P; Sans, J L; Sako, T; Schovanek, P; Smith, D A; Snabre, P; Villard, G

    2002-01-01

    CELESTE is an atmospheric Cherenkov telescope based on the sampling method which makes use of the de-commissioned THEMIS solar electrical plant in the French Pyrenees. A large (2000 m sup 2) mirror surface area from 40 independent heliostats followed by a secondary optic, a trigger system using analog summing techniques and signal digitization with 1 GHz flash ADCs make possible the detection of cosmic gamma-rays down to 30 GeV. This paper provides a detailed technical description of the CELESTE installation.

  18. Development of the Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE)

    CERN Document Server

    Ong, R A

    1998-01-01

    STACEE is a proposed atmospheric Cherenkov telescope for ground-based gamma-ray astrophysics between 25 and 500 GeV. The telescope will make use of the large solar mirrors (heliostats) available at a solar research facility to achieve an energy threshold lower than any existing ground-based instrument. This paper describes the development of STACEE, including an overview of the complete instrument design and a discussion of results from recent prototype tests at the large solar heliostat field of Sandia National Laboratories.

  19. Relativistic Cherenkov radiation in a magneto-dielectric media

    Directory of Open Access Journals (Sweden)

    2016-09-01

    Full Text Available In this paper, relativistic Cherenkov radiation was studied in a 3-D magneto-dielectric medium. Electric permittivity and magnetic permeability of the medium as functions of frequency, are assumed to satisfy Kramers- Kronig equations. A new interaction Hamiltonian, which is different from Hamiltonian term in non-relativistic state, was introduced by the quantized vector potential field and particle field operator obtained from the second quantization method. The rate of electron energy dissipation was calculated using Fermi’s golden rule.

  20. Control Software for the VERITAS Cherenkov Telescope System

    CERN Document Server

    Krawczynski, H; Sembroski, G; Gibbs, K

    2003-01-01

    The VERITAS collaboration is developing a system of initially 4 and eventually 7 Cherenkov Telescopes of the 12 m diameter class for high sensitivity gamma-ray astronomy in the >50 GeV energy range. In this contribution we describe the software that controls and monitors the various VERITAS sub-systems. The software uses an object-oriented approach to cope with the complexities that arise from using sub-groups of the 7 VERITAS telescopes to observe several sources at the same time. Inter-process communication is based on the CORBA Object Request Broker protocol and watch-dog processes monitor the sub-system performance.