21. The surface detector array of the Telescope Array experimentT. Abu-Zayyad, Jon Paul Lundquist, 2012, izvirni znanstveni članek Opis: The Telescope Array (TA) experiment, located in the western desert of Utah, USA, is designed for the observation of extensive air showers from extremely high energy cosmic rays. The experiment has a surface detector array surrounded by three fluorescence detectors to enable simultaneous detection of shower particles at ground level and fluorescence photons along the shower track. The TA surface detectors and fluorescence detectors started full hybrid observation in March, 2008. In this article we describe the design and technical features of the TA surface detector. Ključne besede: Ultra-high energy cosmic rays, Telescope Array experiment, Extensive air shower array Objavljeno v RUNG: 19.05.2020; Ogledov: 2847; Prenosov: 0 Gradivo ima več datotek! Več... |
22. The energy spectrum of ultra-high-energy cosmic rays measured by the Telescope Array FADC fluorescence detectors in monocular modeT. Abu-Zayyad, Jon Paul Lundquist, 2013, izvirni znanstveni članek Opis: We present a measurement of the energy spectrum of ultra-high-energy cosmic rays performed by the Telescope Array experiment using monocular observations from its two new FADC-based fluorescence detectors. After a short description of the experiment, we describe the data analysis and event reconstruction procedures. Since the aperture of the experiment must be calculated by Monte Carlo simulation, we describe this calculation and the comparisons of simulated and real data used to verify the validity of the aperture calculation. Finally, we present the energy spectrum calculated from the merged monocular data sets of the two FADC-based detectors, and also the combination of this merged spectrum with an independent, previously published monocular spectrum measurement performed by Telescope Array’s third fluorescence detector [T. Abu-Zayyad et al., The energy spectrum of Telescope Array’s middle drum detector and the direct comparison to the high resolution fly’s eye experiment, Astroparticle Physics 39 (2012) 109-119, http://dx.doi.org/10.1016/j.astropartphys.2012.05.012, Available from: ]. This combined spectrum corroborates the recently published Telescope Array surface detector spectrum [T. Abu-Zayyad, et al., The cosmic-ray energy spectrum observed with the surface detector of the Telescope Array experiment, ApJ 768 (2013) L1, http://dx.doi.org/10.1088/2041-8205/768/1/L1, Available from: ] with independent systematic uncertainties. Ključne besede: UHECR, Energy spectrum, Fluorescence, Monocular Objavljeno v RUNG: 19.05.2020; Ogledov: 2709; Prenosov: 0 Gradivo ima več datotek! Več... |
23. Correlations of the arrival directions of ultra-high energy cosmic ray with extragalactic objects as observed by the telescope array experimentT. Abu-Zayyad, Jon Paul Lundquist, 2013, izvirni znanstveni članek Opis: We search for correlations between the positions of extragalactic objects and the arrival directions of ultra-high energy cosmic rays (UHECRs) with primary energy E ≥ 40 EeV as observed by the surface detector array of the Telescope Array (TA) experiment during the first 40 months of operation. We examine several public astronomical object catalogs, including the Veron-Cetty and Veron catalog of active galactic nuclei. We count the number of TA events correlated with objects in each catalog as a function of three parameters: the maximum angular separation between a TA event and an object, the minimum energy of the events, and the maximum redshift of the objects. We determine the combination of these parameters that maximizes the correlations, and we calculate the probability of having the same levels of correlations from an isotropic distribution of UHECR arrival directions. No statistically significant correlations are found when penalties for scanning over the above parameters and for searching in several catalogs are taken into account. Ključne besede: acceleration of particles, astroparticle physics, cosmic rays Objavljeno v RUNG: 19.05.2020; Ogledov: 3002; Prenosov: 125 Celotno besedilo (779,07 KB) |
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25. Search for ultra-high-energy neutrinos with the Telescope Array surface detectorR. U. Abbasi, Mitsuhiro Abe, T. Abu-Zayyad, M. Allen, R. Azuma, E. Barcikowski, J. W. Belz, Douglas R. Bergman, S. A. Blake, Jon Paul Lundquist, 2020, izvirni znanstveni članek Opis: We present an upper limit on the flux of ultra-high-energy down-going neutrinos for E > 10^18 eV derived with the nine years of data collected by the Telescope Array surface detector (05-11-2008–
05-10-2017). The method is based on the multivariate analysis technique, so-called Boosted Decision Trees (BDT). Proton-neutrino classifier is built upon 16 observables related to both the properties of the shower front and the lateral distribution function. Ključne besede: neutrinos, pattern recognition, UHECR, cosmic rays Objavljeno v RUNG: 29.04.2020; Ogledov: 3137; Prenosov: 76 Povezava na celotno besedilo Gradivo ima več datotek! Več... |