131. Search for Correlations of High-energy Neutrinos and Ultra-high Energy Cosmic RaysLukas Zehrer, Marko Zavrtanik, Danilo Zavrtanik, Lili Yang, Serguei Vorobiov, Marta Trini, Samo Stanič, Jon Paul Lundquist, Gašper Kukec Mezek, Andrej Filipčič, A.M. Barbano, 2019, objavljeni znanstveni prispevek na konferenci Najdeno v: ključnih besedah
Ključne besede: ultra-high energy cosmic rays (UHECR), high-energy neutrinos, arrival directions, correlation search, IceCube neutrino
observatory, Pierre Auger Observatory, Telescope Array, ANTARES neutrino observatory
Objavljeno: 22.12.2020; Ogledov: 154; Prenosov: 6
 Polno besedilo (400,93 KB) |
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133. CALET’s sensitivity to Dark Matter annihilation in the galactic haloSaptashwa Bhattacharyya, Shoji Torii, Yoichi Asaoka, Holger Motzka, 2015, izvirni znanstveni članek Najdeno v: ključnih besedah
Povzetek najdenega: ...dark matter detectors, dark matter simulations, cosmic rays detectors...
Ključne besede: dark matter detectors, dark matter simulations, cosmic rays detectors
Objavljeno: 06.01.2021; Ogledov: 123; Prenosov: 0
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136. Measurement of the proton-air cross section with Telescope Array's Black Rock Mesa and Long Ridge fluorescence detectors, and surface array in hybrid modeMitsuhiro Abe, R. U. Abbasi, T. Abu-Zayyad, M. Allen, R. Azuma, E. Barcikowski, J. W. Belz, J. P. Lundquist, S. A. Blake, D. R. Bergman, 2020, izvirni znanstveni članek Opis: Ultra high energy cosmic rays provide the highest known energy source in the universe to measure proton cross sections. Though conditions for collecting such data are less controlled than an
accelerator environment, current generation cosmic ray observatories have large enough exposures to collect significant statistics for a reliable measurement for energies above what can be attained in the lab. Cosmic ray measurements of cross section use atmospheric calorimetry to measure depth of air shower maximum (Xmax), which is related to the primary particle’s energy and mass. The tail of the Xmax distribution is assumed to be dominated by showers generated by protons, allowing measurement of the inelastic proton-air cross section. In this work the proton-air inelastic
cross section measurement, σ_inel_p−air, using data observed by Telescope Array’s Black Rock Mesa and Long Ridge fluorescence detectors and surface detector array in hybrid mode is presented. σ_inel_p−air is observed to be 520.1 ± 35.8 [Stat.] +25.0 −40 [Sys.] mb at √s = 73 TeV. The total proton-proton cross section is subsequently inferred from Glauber formalism and is found to be σ_tot_pp = 139.4 +23.4−21.3[Stat.] +15.0−24.0[Sys.] mb.
Najdeno v: ključnih besedah
Povzetek najdenega: ...Ultra high energy cosmic rays provide the highest known energy source...
Ključne besede: cosmic rays, astroparticles, proton-air cross section
Objavljeno: 04.02.2021; Ogledov: 103; Prenosov: 0
Polno besedilo (1,99 MB) |
137. Evidence for a supergalactic structure of magnetic deflection multiplets of ultra-high-energy cosmic raysR. U. Abbasi, T. Abu-Zayyad, Mitsuhiro Abe, M. Allen, R. Azuma, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, J. P. Lundquist, 2020, izvirni znanstveni članek Opis: Evidence for a large-scale supergalactic cosmic-ray multiplet (arrival directions correlated with energy) structure is reported for ultra-high-energy cosmic-ray (UHECR) energies above 1019 eV using 7 years of data from the Telescope Array (TA) surface detector and updated to 10 years. Previous energy–position correlation studies have made assumptions regarding magnetic field shapes and strength, and UHECR composition. Here the assumption tested is that, because the supergalactic plane is a fit to the average matter density of the local large-scale structure, UHECR sources and intervening extragalactic magnetic fields are correlated with this plane. This supergalactic deflection hypothesis is tested by the entire field-of-view (FOV) behavior of the strength of intermediate-scale energy–angle correlations. These multiplets are measured in spherical cap section bins (wedges) of the FOV to account for coherent and random magnetic fields. The structure found is consistent with supergalactic deflection, the previously published energy spectrum anisotropy results of the TA (the Hotspot and Coldspot), and toy-model simulations of a supergalactic magnetic sheet. The seven year data posttrial significance of this supergalactic structure of multiplets appearing by chance, on an isotropic sky, is found by Monte Carlo simulation to be 4.2σ. The 10 years of data posttrial significance is 4.1σ. Furthermore, the starburst galaxy M82 is shown to be a possible source of the TA Hotspot, and an estimate of the supergalactic magnetic field using UHECR measurements is presented.
Najdeno v: ključnih besedah
Ključne besede: extragalactic magnetic fields, ultra-high-energy cosmic radiation, cosmic rays, high energy astrophysics, astrophysical magnetism, cosmic ray astronomy, cosmic ray sources
Objavljeno: 05.02.2021; Ogledov: 111; Prenosov: 4
 Polno besedilo (0,00 KB)
Gradivo ima več datotek! Več...
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138. Search for large-scale anisotropy on arrival directions of ultra-high-energy cosmic rays observed with the telescope array experimentMitsuhiro Abe, R. U. Abbasi, T. Abu-Zayyad, M. Allen, R. Azuma, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, J. P. Lundquist, 2020, izvirni znanstveni članek Opis: Motivated by the detection of a significant dipole structure in the arrival directions of ultra-high-energy cosmic rays above 8 EeV reported by the Pierre Auger Observatory (Auger), we search for a large-scale anisotropy using data collected with the surface detector array of the Telescope Array Experiment (TA). With 11 yr of TA data, a dipole structure in a projection of the R.A. is fitted with an amplitude of 3.3% ± 1.9% and a phase of 131° ± 33°. The corresponding 99% confidence-level upper limit on the amplitude is 7.3%. At the current level of statistics, the fitted result is compatible with both an isotropic distribution and the dipole structure reported by Auger.
Najdeno v: ključnih besedah
Ključne besede: cosmic rays, ultra-high-energy cosmic radiation, cosmic ray sources, cosmic ray showers, cosmic ray detectors, cosmic ray astronomy, extragalactic astronomy
Objavljeno: 05.02.2021; Ogledov: 103; Prenosov: 0
Polno besedilo (548,15 KB) |
139. Scrutinizing FR 0 radio galaxies as ultra-high-energy cosmic ray source candidatesAnita Reimer, Lukas Merten, Margot Boughelilba, Paolo Da Vela, Serguei Vorobiov, Fabrizio Tavecchio, Giacomo Bonnoli, J. P. Lundquist, Chiara Righi, 2021, izvirni znanstveni članek Opis: Fanaroff-Riley (FR) 0 radio galaxies compose a new class of radio galaxies, which are usually weaker but much more numerous than the well-established class of FR 1 and FR 2 galaxies. The latter classes have been proposed as sources of the ultra-high-energy cosmic rays (UHECRs) with energies reaching up to eV. Based on this conjecture, the possibility of UHECR acceleration and survival in an FR 0 source environment is examined in this work.
In doing so, an average spectral energy distribution (SED) based on data from the FR 0 catalog (FR0CAT) is compiled. The resulting photon fields are used as targets for UHECRs, which suffer from electromagnetic pair production, photo-disintegration, photo-meson production losses, and synchrotron radiation. Multiple mechanisms are discussed to assess the UHECR acceleration probability, including Fermi-I order and gradual shear accelerations, and particle escape from the source region.
This work shows that in a hybrid scenario, combining Fermi and shear accelerations, FR 0 galaxies can contribute to the observed UHECR flux, as long as where shear acceleration starts to dominate over escape. Even in less optimistic scenarios, FR 0s can be expected to contribute to the cosmic-ray flux between the knee and the ankle. Our results are relatively robust with respect to the realized magnetic turbulence model and the speed of the accelerating shocks.
Najdeno v: ključnih besedah
Povzetek najdenega: ...proposed as sources of the ultra-high-energy cosmic rays (UHECRs) with energies reaching up to ...
Ključne besede: acceleration of particles, nonthermal radiation mechanisms, jets, active galaxies, cosmic rays
Objavljeno: 05.02.2021; Ogledov: 156; Prenosov: 0
Polno besedilo (4,15 MB)
Gradivo ima več datotek! Več...
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140. ISS-CREAM flight operationD. Angelaszek, K. C. Kim, Y. Amarea, N. Anthony, G. H. Choi, M. Chung, M. Copley, L. Derome, L. Eraud, C. Falana, J. P. Lundquist, 2019, objavljeni znanstveni prispevek na konferenci Opis: The Cosmic Ray Energetics And Mass experiment for the International Space Station (ISS-CREAM) is designed and built to measure the elemental energy spectra of cosmic-ray particles (1 ≤ Z ≤ 26) and electrons. It measures the energy of incident cosmic rays from 10^12 to 10^15 eV. ISS-CREAM was launched and deployed to the ISS in August 2017. The Science Operations Center (SOC) at the University of Maryland has been operating the payload on the International Space Station (ISS) in coordination with the Payload Operations Integration Center (POIC) at NASA’s Marshall Space Flight Center. The SOC has been responsible for sending commands to and receiving data from the Science Flight Computer (SFC) on board ISS-CREAM. The ISS-CREAM data taking program interfaces with the POIC using the Telescience Resources Kit through the Software Toolkit for Ethernet Lab-Like Architecture developed by the Boeing Company. The command uplink and data downlink have been through the Track-ing and Data Relay Satellite System. We present the ISS-CREAM flight operations including ISS communications, SFC performance, etc.
Najdeno v: ključnih besedah
Povzetek najdenega: ...The Cosmic Ray Energetics And Mass experiment for the... ...It measures the energy of incident cosmic rays from 10^12 to 10^15 eV. ISS-CREAM was...
Ključne besede: instrumentations, high energy cosmic rays, particle detectors
Objavljeno: 08.02.2021; Ogledov: 90; Prenosov: 0
Polno besedilo (1,19 MB) |
