21. Evidence for a supergalactic structure of magnetic deflection multiplets of ultra-high-energy cosmic raysR. 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: 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. Ključne besede: extragalactic magnetic fields, ultra-high-energy cosmic radiation, cosmic rays, high energy astrophysics, astrophysical magnetism, cosmic ray astronomy, cosmic ray sources Objavljeno v RUNG: 05.02.2021; Ogledov: 2554; Prenosov: 126 Povezava na celotno besedilo Gradivo ima več datotek! Več... |
22. Follow-up searches for ultra-high energy neutrinos from transient astrophysical sources with the Pierre Auger ObservatoryMichael Schimp, Andrej Filipčič, Gašper Kukec Mezek, Samo Stanič, Marta Trini, Serguei Vorobiov, Lili Yang, Danilo Zavrtanik, Marko Zavrtanik, Lukas Zehrer, 2019, objavljeni znanstveni prispevek na konferenci Ključne besede: Pierre Auger Observatory, transient astrophysical sources, binary black hole mergers, gravitational wave events, blazar TXS 0506+056, follow-up search for counterpart ultra-high energy neutrinos Objavljeno v RUNG: 21.12.2020; Ogledov: 2598; Prenosov: 71 Celotno besedilo (366,82 KB) |
23. |
24. A Search for Ultra-high-energy Neutrinos from TXS 0506+056 Using the Pierre Auger ObservatoryA. Aab, Andrej Filipčič, Gašper Kukec Mezek, Samo Stanič, Marta Trini, Serguei Vorobiov, Danilo Zavrtanik, Marko Zavrtanik, Lukas Zehrer, 2020, izvirni znanstveni članek Ključne besede: ultra-high energy neutrinos, blazar TXS 0506+056, the Pierre Auger Observatory, high-energy astrophysics, neutrino astronomy, blazars, transient sources, active galaxies Objavljeno v RUNG: 20.10.2020; Ogledov: 3046; Prenosov: 0 Gradivo ima več datotek! Več... |
25. Reconstructed properties of the sources of UHECR and their dependence on the extragalactic magnetic fieldDavid Wittkowski, Andrej Filipčič, Gašper Kukec Mezek, Ahmed Saleh, Samo Stanič, Marta Trini, Darko Veberič, Serguei Vorobiov, Lili Yang, Danilo Zavrtanik, Marko Zavrtanik, 2017, objavljeni znanstveni prispevek na konferenci Ključne besede: extragalactic magnetic field, Pierre Auger Observatory, sources of UHECR Objavljeno v RUNG: 16.02.2018; Ogledov: 3424; Prenosov: 161 Celotno besedilo (356,61 KB) |
26. |
27. Method of Regularized Sources for Stokes Flow Problems with Improved Calculation of Velocity Derivatives at the BoundaryBožidar Šarler, wen shiting, li ming, objavljeni povzetek znanstvenega prispevka na konferenci Opis: The solution of Stokes flow problems with Dirichlet and Neumann boundary conditions is performed by a non-singular Method of Fundamental Solutions which does not require artificial boundary, i.e. source points of fundamental solution coincide with the collocation points on the boundary. Instead of Dirac delta force, an exponential function, called blob, with a free parameter epsilon is employed, which limits to Dirac delta function when epsilon limits to zero. The solution of the problem is sought as a linear combination of the fields due to the regularized sources that coincide with the boundary and with their intensities chosen in such a way that the solution complies with the boundary conditions. A two-dimensional flow between parallel plates is chosen to assess the properties of the method. The results of the method are accurate except for the derivatives at the boundary. A correction of the method is proposed which can be used to properly assess also the derivatives at the boundary Ključne besede: stokes flow, method of regularized sources, meshless method Objavljeno v RUNG: 28.06.2016; Ogledov: 4308; Prenosov: 0 Gradivo ima več datotek! Več... |
28. |