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Related papers: Puzzles of the cosmic ray anisotropy

200 papers

Measuring the anisotropy of the arrival direction distribution of cosmic rays provides important information on the propagation mechanisms and the identification of their sources. In fact, the flux of cosmic rays is thought to be dependent…

High Energy Astrophysical Phenomena · Physics 2013-09-25 YBJ Collaboration

One of the models recently proposed to explain the origin of the ultra high energy cosmic rays assumes that these particles may be accelerated by the electromotive force around presently inactive quasar remnants. We study predictions for…

Astrophysics · Physics 2007-05-23 C. Isola , G. Sigl , G. Bertone

Anisotropy in the arrival directions of cosmic rays around 10^{18}eV is studied using data from the Akeno 20 km^2 array and the Akeno Giant Air Shower Array (AGASA), using a total of about 216,000 showers observed over 15 years above…

We briefly review the status of cosmic ray studies between $10^{14}$ eV and the highest observed energies, namely a few times $10^{20}$ eV. Because of the rather low incident fluxes in this energy range, the studies mostly rely on ground…

Astrophysics · Physics 2009-10-31 Murat Boratav , Alan A. Watson

Recent measurements of the Cosmic Microwave Background Anisotropy have provided evidence for the presence of oscillations in the angular power spectrum. These oscillations are a wonderful confirmation of the standard cosmological scenario…

Astrophysics · Physics 2007-05-23 Alessandro Melchiorri

The coincidence problems and other dynamical features of dark energy are studied in cosmological models with variable cosmological parameters and in models with the composite dark energy. It is found that many of the problems usually…

Astrophysics · Physics 2008-11-26 Javier Grande , Joan Sola , Hrvoje Stefancic

Using simulation methods, distortion effects on energy spectra caused by errors in the energy determination have been investigated. For cosmic ray proton spectra, falling steeply with kinetic energy E as E-2.7, significant effects appear.…

Astrophysics · Physics 2009-11-11 Per Carlson , Conny Wannemark

The search for cosmic ray anisotropy has been performed using particles collected by the Alpha Magnetic Spectrometer after the first five years of operation. The positron to electron ratio is consistent with isotropy at all energies and…

High Energy Astrophysical Phenomena · Physics 2016-12-30 G. La Vacca , AMS-02 Collaboration

The propagation of cosmic rays (CRs) in turbulent interstellar magnetic fields is typically described as a spatial diffusion process. This formalism predicts only a small deviation from an isotropic CR distribution in the form of a dipole…

High Energy Astrophysical Phenomena · Physics 2014-01-22 Markus Ahlers

During the past two decades, experiments in both the Northern and Southern hemispheres have observed a small but measurable energy-dependent sidereal anisotropy in the arrival direction distribution of galactic cosmic rays. The relative…

High Energy Astrophysical Phenomena · Physics 2015-10-16 The HAWC Collaboration , The IceCube Collaboration

The origin of cosmic ray events with $E \gsim 10^{11}$ GeV remains mysterious. In this talk I briefly summarize several proposed particle physics explanations: a breakdown of Lorentz invariance, the ``$Z-$burst'' scenario, new hadrons with…

High Energy Physics - Phenomenology · Physics 2008-11-26 Manuel Drees

This work presents a scenario of ultra-high energy cosmic ray source distribution where a nearby source is solely responsible for the anisotropies in arrival directions of cosmic rays while the rest of the sources contribute only…

High Energy Astrophysical Phenomena · Physics 2019-01-09 Andrej Dundović , Günter Sigl

Cosmic microwave background anisotropies provide a vast amount of cosmological information. Their full physical content and detailed structure can be understood in a simple and intuitive fashion through a systematic investigation of the…

Astrophysics · Physics 2009-10-28 Wayne Hu , Naoshi Sugiyama , Joseph Silk

In the presence of anisotropic cosmic expansions at global or local scale the equations of electrodynamics in expanding space-time are modified and presented here. A new effect should arise in regions of local anisotropic expansion in a…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-01 Paolo Ciarcelluti

We study the effect of the stochastic character of supernova explosions on the anisotropy of galactic cosmic rays below the knee. We conclude that if the bulk of cosmic rays are produced in supernova explosions the observed small and nearly…

Astrophysics · Physics 2009-11-11 A. D. Erlykin , A. W. Wolfendale

We constrain the energy at which the transition from Galactic to extragalactic cosmic rays occurs by computing the anisotropy at Earth of cosmic rays emitted by Galactic sources. Since the diffusion approximation starts to loose its…

High Energy Astrophysical Phenomena · Physics 2012-07-17 G. Giacinti , M. Kachelriess , D. V. Semikoz , G. Sigl

The origin of cosmic rays is one of the major unresolved astrophysical questions. In particular, the highest energy cosmic rays observed possess macroscopic energies and their origin is likely to be associated with the most energetic…

Astrophysics · Physics 2007-05-23 Guenter Sigl

The IceCube Observatory provides our highest-statistics picture of the cosmic-ray arrival directions in the Southern Hemisphere, with over 700 billion cosmic-ray-induced muon events collected between May 2011 and May 2022. Using the larger…

The inhomogeneous ionization state of the universe when the first sources of ionizing radiation appeared should lead to anisotropies in the polarization of the cosmic microwave background. We use cosmological simulations of the process by…

Two sides of cosmological constant problem are discussed: a mysterious compensation of all contributions to vacuum energy with the accuracy of 100-50 orders of magnitude and a surprising equality of a constant vacuum energy density to the…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. D. Dolgov