Loading...
Search for: photomultipliers
0.009 seconds

    Optimization of dimensions and inner surface of water cherenkov detector with one photomultiplier tube (PMT)

    , Article Proceedings of the 32nd International Cosmic Ray Conference, ICRC 2011 ; Volume 5 , 2011 , Pages 240-243 Mortazavi Moghaddam, S ; Khalaj, P ; Bahmanabadi, M ; Purmohammad, D ; Abdollahi, S ; China Center of Advanced Science and Technology (CCAST); Chinese Academy of Sciences (CAS); Institute of High Energy Physics (IHEP); National Natural Science Foundation of China (NSFC) ; Sharif University of Technology
    Abstract
    In order to be more precise to find primary cosmic particles directions, nowadays detectors and data analysis for studying secondary particles in extensive air showers have an ongoing progress and water Cherenkov detector is considered as a secondary particle detector. Our aim in this paper is to optimize the size and the inner surface characteristic of a cylindrical water Cherenkov tank with one PMT. By comparing simulation outputs with experiments results, we show that the diffusing inner surface is more practical than the reflective inner surface and we conclude that the optimum height for a diffusing tank with a diameter of 45cm is 60cm  

    Optimization of dimensions and inner surface of water Cherenkov detector with one photomultiplier tube (PMT) for the Alborz observatory air shower array

    , Article Astroparticle Physics ; Volume 35, Issue 12 , July , 2012 , Pages 792-796 ; 09276505 (ISSN) Mortazavi Moghaddam, S ; Khalaj, P ; Bahmanabadi, M ; Purmohammad, D ; Abdollahi, S ; Sharif University of Technology
    2012
    Abstract
    In order to be more precise to find primary cosmic particles directions, nowadays detectors and data analysis for studying secondary particles in extensive air showers have an ongoing progress and water Cherenkov detector is considered as a secondary particles detector. Our aim in this paper is to optimize the size and the inner surface characteristic of a cylindrical water Cherenkov tank with one PMT in order to use at the Alborz observatory air shower array which consists of 20 plastic scintillation detectors and 10 water Cherenkov detectors. By comparing data gathered by tanks with diffusing and specular reflection inner surfaces, we show that the diffusing inner surface is more... 

    Optimization of the size of scintillation detectors in order to use in an array of 20 detectors which is going to be placed in the Sharif University of Technology

    , Article Proceedings of the 32nd International Cosmic Ray Conference, ICRC 2011, 11 August 2011 through 18 August 2011, Beijing ; Volume 3 , 2011 , Pages 40-43 Pezeshkian, Y ; Mortazavi Moghaddam, S ; Hedayati, H ; Bahmanabadi, M ; Khalaj, P ; Sharif University of Technology
    Institute of High Energy Physics  2011
    Abstract
    As a primary step of establishment of an extensive air shower array consisting 20 scintillation detectors we optimized an individual detector. Square shaped scintillators are placed under a metal pyramid Light Enclosure with a photomultiplier tube (PMT) at the vertex of it. A set of experiments are performed to optimize the height of light enclosures by comparing 4 different heights 0.1, 0.2, 0.3 and 0.4 m. These experiments are supported by a Monte Carlo simulation of detection process. In this article, by considering experimental and simulation results we concluded that 20 cm is an optimum height for light enclosures  

    Characterization of etched glass surfaces by wave scattering

    , Article Surface and Interface Analysis ; Volume 37, Issue 7 , 2005 , Pages 641-645 ; 01422421 (ISSN) Jafari, G. R ; Mahdavi, S. M ; Iraji Zad, A ; Kaghazchi, P ; Sharif University of Technology
    2005
    Abstract
    The roughness of glass surfaces after different stages of etching is investigated by reflection measurements with a spectrophotometer, light scattering, atomic force microscopy (AFM, on a small scale) and profilometry (on a large scale). The results suggest that there are three regimes during etching, according to their optical reflectivity and roughness. The first and the second regimes are studied by the Kirchhoff theory and the third one is studied by the optical geometric theory. Also, the roughness obtained by optical scattering is compared with the AFM results. Copyright © 2005 John Wiley & Sons, Ltd  

    Introducing of Novel Method to Improve the Process of Imaging in a Gamma Camera Equipped with Square PMTs

    , M.Sc. Thesis Sharif University of Technology Amir Mozafari Sabet, Kiarash (Author) ; Bagheri Shouraki, Saeed (Supervisor) ; Fatemizadeh, Emad (Supervisor) ; Ay, Mohammad Reza (Co-Supervisor)
    Abstract
    The gamma cameras, based on scintillation crystal followed by an array of photomultiplier tubes (PMTs), play a crucial role in nuclear medicine. The use of square PMTs provides the minimum dead zones in the camera. The camera with squared PMTs also reduces the number of PMTs relative to the detection area.In this thesis, we introduced a new read-out method whereby the total cost of the read-out board will be decreased by a factor of 2.4; in return, the energy and spatial resolution of the system will be reduced by 0.3% and 0.4% respectively. We also implemented a positioning module in the FPGA chip via that the transmission rate between FPGA and the computer will be tripled, and the...