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    Muon charge ratio using the corsika simulation code

    , Article Physical Review D ; Volume 100, Issue 8 , 2019 ; 24700010 (ISSN) Bahmanabadi, M ; Fazlalizadeh, M ; Sharif University of Technology
    American Physical Society  2019
    Abstract
    Using the corsika code, in 21 energy states between 7 and 900 GeV, in each state, 2×104 extensive air showers were simulated separately with 88% protons and 12% alpha as primary particles. The zenith and azimuth angles of the primary particles were between 0° to 60° and 0° to 360°, respectively. These simulations are carried out at Tehran's level (35°43′N, 51°20′E; 1200 m a.s.l=897 g cm-2) and with two models GHEISHA and UrQMD for hadronic interactions at low energy and the QGSJET-II model for high-energy interactions. Using the positive and negative muons produced from these air showers, the muon charge ratios are obtained at various angles and energies. An east-west anisotropy is also... 

    Determining the angular resolution of an air shower array including five scintillation detectors using two methods: Shadow of the moon and the CORSIKA simulation

    , Article Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment ; Volume 932 , 2019 , Pages 62-68 ; 01689002 (ISSN) Bahmanabadi, M ; Heydarizad, M ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    An array including five scintillation detectors at Sharif University of Technology in Tehran (35°43′N, 51°20′E, 1200m a.s.l= 897 gcm−2), over a year from October 2016 to October 2017, collected more than 5.6×105 extensive air shower (EAS) events in the energy range between 0.03PeV and 3PeV. Data from the array were used to examine the cosmic ray shadow of the Moon in the energy range mentioned. The observation of a deficit of cosmic rays in the direction of the moon can be an estimate of the accuracy of the measurement of the primary particles of the air showers. The deficit of cosmic rays from the direction of the moon, in fact, is due to the presence of the moon in the early direction of... 

    Simulation of the time structure of Extensive Air Showers with CORSIKA initiated by various primary particles at Alborz-I observatory level

    , Article New Astronomy ; Volume 61 , 2018 , Pages 5-13 ; 13841076 (ISSN) Bahmanabadi, M ; Moghaddam, S. M ; Sharif University of Technology
    Elsevier B.V  2018
    Abstract
    A detailed simulation of showers with various zenith angles in atmosphere produced by different primary particles including gamma, proton, carbon, and iron at Alborz-I observatory level (35∘43′N, 51∘20′E, 1200 m a.s.l= 890 gcm−2), in the energy range 3 × 1013 eV–3 × 1015 eV, has been performed by means of the CORSIKA Monte Carlo code. The aim of this study is to examine the time structure of secondary particles in Extensive Air Showers (EAS) produced by the different primary particles. For each primary particle, the distribution of the mean values of the time delays of secondary particles relative to the first particle hitting the ground level in each EAS, <τi>=, and the distribution... 

    Experimental examination of utilizing novel radially grooved surfaces in the evaporator of a thermosyphon heat pipe

    , Article Applied Thermal Engineering ; Volume 169 , 2020 Bahmanabadi, A ; Faegh, M ; Shafii, M. B ; Sharif University of Technology
    Elsevier Ltd  2020
    Abstract
    The application of heat pipes with flat evaporators in cooling electronic devices has attracted a lot of attention in recent years. Increasing the rate of heat transfer in their evaporator by utilizing structured surfaces is considered as a prominent method for reducing the thermal resistance of the heat pipes. In this study, the performance of a thermosyphon heat pipe with novel radially rectangular-grooved and radially inclined triangular-grooved evaporator surfaces was evaluated experimentally. It is hypothesized that the radial grooves may enhance the performance by inducing rotational motions and increasing the heat transfer coefficients. Based on the results, the optimum filling ratio... 

    Observation of cosmic ray flux deficit in the direction of the sun using a charged particle traking telescope

    , Article Astroparticle Physics ; Volume 86 , 2017 , Pages 27-31 ; 09276505 (ISSN) Bahmanabadi, M ; Sharif University of Technology
    Elsevier B.V  2017
    Abstract
    A cosmic ray tracking telescope has been made for the measurement of the secondary cosmic ray flux at ground level. The observations have been made both looking in the direction of the sun and away from the sun. Our observations by the telescope shows a deficiency in the detected number of cosmic rays entering the telescope when its axis was pointing to the sun compared to that entering the telescope with no sun in its field of view. The statistical significance of this deficit with the Li and Ma method stands near 1.3σ for all of our observations. © 2016 Elsevier B.V  

    Determining the muon charge ratio using an experimental measurements and the CORSIKA simulation code

    , Article Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment ; Volume 945 , 2019 ; 01689002 (ISSN) Bahmanabadi, M ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    The muon charge ratio contains important information about the flux of atmospheric neutrinos and the hadronic interactions. Using a cosmic ray telescope, the atmospheric muon charge ratio has been studied. The result of this experiment is compared with simulation results using the CORSIKA code. © 2019 Elsevier B.V  

    A method for determining the angular distribution of atmospheric muons using a cosmic ray telescope

    , Article Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment ; Volume 916 , 2019 , Pages 1-7 ; 01689002 (ISSN) Bahmanabadi, M ; Sharif University of Technology
    Elsevier B.V  2019
    Abstract
    A cosmic ray telescope consisting of two scintillators (each one with a surface area of 0.14 m2, spaced 283 cm top of each other) was constructed to study the angular distribution of atmospheric muons. Using the CORSIKA code, the muons energy spectrum is parameterized in different energy regions at Tehran's altitude (1200 m above sea level ≡897 gcm−2), and by using a Monte Carlo program, the minimum energy recorded by the telescope is calculated. Due to the geomagnetic field, in the azimuth angle distribution of atmospheric muons, an anisotropy is observed in the East–West direction. The zenith angle distribution of the atmospheric muons follows the function cosnθ. Due to the relatively... 

    Investigation of EGRET gamma-ray sources by an extensive air shower experiment

    , Article 29th International Cosmic Ray Conference, ICRC 2005, Pune, 3 August 2005 through 10 August 2005 ; Volume 6 , 2005 , Pages 29-32 Khakian Ghomi, M ; Samimi, J ; Bahmanabadi, M ; Sharif University of Technology
    Tata Institute of Fundamental Research  2005
    Abstract
    Ultra-high-energy ( E ≥ TeV) Extensive Air Showers (EASs) have been monitored for a period of five years (1997-2003 ), using a small array of scintillator detectors in Tehran, Iran. The data have been analyzed to take in to account of the dependence of source counts on zenith angle. During a calendar year different sources come in the field of view of the detector at varying zenith angles. Because of varying thickness of the overlaying atmosphere, the shower count rate is extremely dependent on zenith angle which have been carefully analyzed over time. High energy gamma-ray sources from the EGRET third catalogue where observed and the data were analyzed using an excess method. Upper limits... 

    Experimental studies of positive and negative atmospheric muons with a cosmic rays telescope

    , Article Astroparticle Physics ; Volume 24, Issue 3 , 2005 , Pages 183-190 ; 09276505 (ISSN) Bahmanabadi, M ; Khakian Ghomi, M ; Sheidaei, F ; Sharif University of Technology
    2005
    Abstract
    An experiment has been developed for the measurement of the muon charge ratio (ratio of positive to negative muons) in the cosmic ray flux in energy range 0.236-0.242 GeV. The muon charge ratio is found to be 1.35 ± 0.10 with a mean zenith angle of 32° ± 5°. Meanwhile, the distributions of muons in zenith (θ) and azimuth angles have been studied. A cosnθ distribution with n = 1.95 ± 0.13 has been obtained. An asymmetry has been observed in East-West directions because of geomagnetic field. © 2005 Elsevier B.V. All rights reserved  

    Galactic anisotropy of cosmic ray intensity observed by an air shower experiment

    , Article Publications of the Astronomical Society of Australia ; Volume 23, Issue 3 , 2006 , Pages 129-134 ; 13233580 (ISSN) Bahmanabadi, M ; Khakian Ghomi, M ; Sheidaei, F ; Samimi, J ; Sharif University of Technology
    2006
    Abstract
    We have monitored multi-TeV cosmic rays by a small air shower array in Tehran (35°43′ N, 51°20′ E, 1200 m ≤ 890 g cm -2). More than 1.1 × 106 extensive air shower events were recorded. These observations enabled us to analyse sidereal variation of the galactic cosmic ray intensity. The observed sidereal daily variation is compared to the expected variation which includes the Compton-Getting effect due to the motion of the earth in the Galaxy. In addition to the Compton-Getting effect, an anisotropy has been observed which is due to a unidirectional anisotropy of cosmic ray flow along the Galactic arms  

    The charge ratio of the atmospheric muons at low energy

    , Article Physical Review D - Particles, Fields, Gravitation and Cosmology ; Volume 74, Issue 8 , 2006 ; 15507998 (ISSN) Bahmanabadi, M ; Sheidaei, F ; Khakian Ghomi, M ; Samimi, J ; Sharif University of Technology
    2006
    Abstract
    From the nature of the muon production processes, it can be seen that the ratio of positive to negative cosmic muons has important information in both "the atmospheric neutrino problem," and "the hadronic interactions." We have carried out an experiment for the measurement of the muon charge ratio in the cosmic ray flux in momentum range 0.112-0.178GeV/c. The muon charge ratio is found to be 1.21±0.01 with a mean zenith angle of 32°±5°. From the measurements it has been obtained a zenithal angle distribution of muons as I(θ)=I(0)cos nθ with n=1.95±0.13. An asymmetry has been observed in East-West directions because of the geomagnetic field. Meanwhile, in about the same momentum range,... 

    An investigation on anisotropy of cosmic rays with a small air shower array

    , Article Experimental Astronomy ; Volume 15, Issue 1 , 2003 , Pages 13-27 ; 09226435 (ISSN) Bahmanabadi, M ; Ghomi, M. K ; Samimi, J ; Purmohammad, D ; Sharif University of Technology
    2003
    Abstract
    We have studied anisotropy of cosmic rays with an Extensive AirShower(EAS) array in Tehran 1200 m above sea level. In analyzingthe data set, we have used appropriate techniques of analysis andconsidered environmental effects. An asymmetry has been observedin the azimuthal distribution of EAS of cosmic rays because ofmagnetic field of the Earth. © 2004 Kluwer Academic Publishers  

    A new method for finding core locations of extensive air showers

    , Article Astrophysical Journal ; Volume 727, Issue 2 , 2011 ; 0004637X (ISSN) Hedayati Kh., H ; Anvari, A ; Bahmanabadi, M ; Samimi, J ; Khakian Ghomi, M ; Sharif University of Technology
    Institute of Physics Publishing  2011
    Abstract
    Analysis of an extensive air shower (EAS) detected by surface arrays highly depends on the determination of core locations. Here we present a new method to find the core location of an EAS that, unlike the common methods, does not depend on the lateral distribution function and uses arrival times of secondary particles. This method improves the accuracy of finding the core location of a low-energy EAS in the internal parts of an array, in comparison with common methods  

    A new simple method for the analysis of extensive air showers

    , Article Astroparticle Physics ; Volume 34, Issue 9 , 2011 , Pages 699-704 ; 09276505 (ISSN) Hedayati Kh., H ; Anvari, A ; Bahmanabadi, M ; Samimi, J ; Khakian Ghomi, M ; Sharif University of Technology
    2011
    Abstract
    The most important goal of studying an extensive air shower is to find the energy, mass and arrival direction of its primary cosmic ray. In order to find these parameters, the core position and arrival direction of the shower should be determined. In this paper, a new method for finding core location has been introduced that utilizes trigger time information of particle detectors. We have also developed a simple technique to reconstruct the arrival direction. Our method is not based upon density-sensitive detectors which are sensitive to the number of crossing particles and is also independent of lateral distribution models. This model has been developed and examined by the analysis of... 

    Finding gamma ray events by the method of obtaining poisson distribution from data collected by an array of Cherenkov detectors

    , Article 31st International Cosmic Ray Conference, ICRC 2009, 7 July 2009 through 15 July 2009, Lodz ; 2009 Bayesteh, S ; Qomi, M. K ; Samimi, J ; Hamedivafa, H ; Sheidaei, F ; Bahmanabadi, M ; Sharif University of Technology
    2009
    Abstract
    a small array of Water Cherenkov Detectors (WCDs) has recorded 600000 events related to extensive air showers in Tehran during one year at an altitude of 1200m. By employing the method of obtaining count in each time interval distributions we obtained the distribution of extensive air showers. 17 events were found in our data set which are more probable to be related to primary gamma ray photons. For more certainty we did a simulation to compare acquired results from simulation and data to become sure if 17 extensive air showers are electromagnetic or not  

    Study on extensive air showers with a small array of water cherenkov detectors

    , Article 4th International Meeting on High Energy Gamma-Ray Astronomy, Heidelberg, 7 July 2008 through 11 July 2008 ; Volume 1085 , 2009 , Pages 708-711 ; 0094243X (ISSN) Sheidaei, F ; Bayesteh, Sh ; Bahmanabadi, M ; Khakian Ghomi, M ; Samimi, J ; Hamedivafa, H ; Sharif University of Technology
    2009
    Abstract
    We recorded 600,000 (EASs) from Dec. 2006 to Oct. 2007 with a small array of water Cherenkov detectors. We found zenith and azimuth distributions of these events that confirm previous distributions from array of scintillator detectors. The study on EGRET sources are under consideration, besides, we have improved the size of our detectors to yield the best efficiency. The best shape for each detector will be a tank with 40 cm in diameter and 60 cm in height with a PMT in the center of lid. © 2009 American Institute of Physics  

    System Identification and Control of Space Explorer Robot Arm Using Neural Network

    , M.Sc. Thesis Sharif University of Technology Bahmanabadi, Hossein (Author) ; Asadian, Nima (Supervisor)
    Abstract
    In this study, two conventional methods for controlling flexible two-link robots based on artificial neural networks is improved. The first method is implemented by combining fuzzy logic and reinforcement learning in the form of a neural network. This method is modified in two steps. In the first step, the system feedback is changed and in the second step, the system Jacobin is used. This Jacobin can be the result of system identification. In the second method, an optimal controller is proposed for the system, which is also implemented in the form of a neural network. The performance of the neural-optimal controller is further improved by redefining the Bellman's principle of optimality.... 

    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  

    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... 

    A study of the effect of geomagnetic field on extensive air showers with small arrays

    , Article Experimental Astronomy ; Volume 13, Issue 1 , 2002 , Pages 39-57 ; 09226435 (ISSN) Bahmanabadi, M ; Anvari, A ; Ghomi, M. K ; Purmohammad, D ; Samimi, J ; Rachti, M. L ; Sharif University of Technology
    2002
    Abstract
    We have studied Extensive Air Showers (EAS) with two small arrays of 1 m2 scintillation detectors in Tehran, 1200 m above sea level. The distribution of air showers in zenith and azimuth angles has been studied and a cosn θ distribution with n = 7.2×0.2 was obtained for zenith angle distribution. An asymmetry has been observed in the azimuthal distribution of EAS of cosmic rays because of magnetic field of the Earth. Amplitudes of the first and the second harmonics of observed distribution depend on zenith angle as AI≈(0.02 + 0.35 sin2 θ)×0.02, and AII(0.03 + 0.42 sin4 θ)×0.03. Meanwhile, the uncertainties arising from the instrument, transit location of shower particles in the scintillator...