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Related papers: Explaining TeV Cosmic-Ray Anisotropies with Non-Di…

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External cosmic rays impinging upon circumstellar disks associated with young stellar objects provide an important source of ionization, and as such, play an important role in disk evolution and planet formation. However, these incoming…

High Energy Astrophysical Phenomena · Physics 2018-04-25 Marco Fatuzzo , Fred C. Adams

Cosmic ray (CR) transport and acceleration is determined by the properties of magnetic turbulence. Recent advances in MHD turbulence call for revisions in the paradigm of cosmic ray transport. We use the models of magnetohydrodynamic…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Huirong Yan

We study anisotropy of cosmic rays in the energy range 0.2-1.4 EeV at intermediate angular scales using the public data set of the Pierre Auger Observatory. At certain scales, the analysis reveals a number of deviations from the isotropic…

High Energy Astrophysical Phenomena · Physics 2014-09-23 M. Yu. Zotov

In recent years, a number of experiments have been conducted with the goal of studying cosmic rays at GeV to TeV energies. This is a particularly interesting regime from the perspective of indirect dark matter detection. To draw reliable…

High Energy Astrophysical Phenomena · Physics 2009-11-05 Melanie Simet , Dan Hooper

The arrival directions of TeV-PeV cosmic rays show weak but significant anisotropies with relative intensities at the level of one per mille. Due to the smallness of the anisotropies, quantitative studies require careful disentanglement of…

High Energy Astrophysical Phenomena · Physics 2016-05-19 Markus Ahlers , Segev Y. BenZvi , Paolo Desiati , Juan Carlos Díaz-Vélez , Daniel W. Fiorino , Stefan Westerhoff

We discuss recently published results of two-dimensional measurements of the cosmic ray anisotropy in the energy range 1-100 TeV. It is demonstrated that, in spite of pretence of the authors to measure the anisotropy in more detail than it…

Astrophysics · Physics 2008-04-29 Yu. M. Andreyev , V. A. Kozyarivsky , A. S. Lidvansky

The slow particle diffusion in pulsar halos, inferred from TeV gamma-ray surface brightness profiles, is attributed to cross-field diffusion under the anisotropic diffusion model. This model assumes sub-Alfv\'enic interstellar turbulence in…

High Energy Astrophysical Phenomena · Physics 2025-07-17 Kai Yan , Sha Wu , Ruo-Yu Liu

The standard model of cosmology is based on the hypothesis that the Universe is spatially homogeneous and isotropic. When interpreting most observations, this cosmological principle is applied stricto sensu: the light emitted by distant…

General Relativity and Quantum Cosmology · Physics 2024-01-15 Pierre Fleury

Motivated by the ~7 % dipole anisotropy in the distribution of ultra-high energy cosmic-rays (UHECRs) above 8 EeV, we explore the anisotropy induced by the large scale structure, using constrained simulations of the local Universe and…

High Energy Astrophysical Phenomena · Physics 2019-01-23 Noémie Globus , Tsvi Piran , Yehuda Hoffman , Edoardo Carlesi , Daniel Pomarède

The density of cosmic rays inside molecular clouds determines the ionization rate in the dense cores where stars form. It is also one of the drivers of astrochemistry leading to the creation of complex molecules. Through Fermi Large Area…

High Energy Astrophysical Phenomena · Physics 2023-01-18 Rui-zhi Yang , Guang-Xing Li , Emma de Oña Wilhelmi , Yu-Dong Cui , Bing Liu , Felix Aharonian

The hypothesis that the entire cosmic ray spectrum, from $\lesssim1\,{\rm GeV}$ to $\gtrsim100\,{\rm EeV}$ energy, can be accounted for by diffusive shock acceleration on increasingly large scales is critically examined. Specifically, it is…

High Energy Astrophysical Phenomena · Physics 2023-09-19 Roger Blandford , Paul Simeon , Noémie Globus , Payel Mukhopadhyay , Enrico Peretti , Kirk S. S. Barrow

The cosmic rays differential intensity inside the heliosphere, for energy below 30 GeV/nuc, depends on solar activity and interplanetary magnetic field polarity. This variation, termed solar modulation, is described using a 2-D (radius and…

Solar and Stellar Astrophysics · Physics 2015-06-12 P. Bobik , G. Boella , M. J. Boschini , C. Consolandi , S. Della Torre , M. Gervasi , D. Grandi , K. Kudela , S. Pensotti , P. G. Rancoita , D. Rozza , M. Tacconi

The diffusion of cosmic rays (CRs) in turbulent magnetic fields is fundamental to understand various astrophysical processes. We explore the CR diffusion in the magnetic fluctuations amplified by the nonlinear turbulent dynamo, in the…

High Energy Astrophysical Phenomena · Physics 2024-12-03 Chao Zhang , Siyao Xu

If the diffuse extragalactic gamma ray emission traces the large scale structures of the universe, peculiar anisotropy patterns are expected in the gamma ray sky. In particular, because of the cutoff distance introduced by the absorption of…

Astrophysics · Physics 2014-10-13 A. Cuoco , S. Hannestad , T. Haugbølle , G. Miele , P. D. Serpico , H. Tu

Understanding the time scales for diffusive processes and their degree of anisotropy is essential for modelling cosmic-ray transport in turbulent magnetic fields. We show that the diffusion time scales are isotropic over a large range of…

High Energy Astrophysical Phenomena · Physics 2022-06-01 P. Reichherzer , J. Becker Tjus , E. G. Zweibel , L. Merten , M. J. Pueschel

We obtain the angular distribution of the cosmic rays reaching an observer from an individual source and after propagation through a turbulent magnetic field, for different ratios between the source distance and the diffusion length. We…

High Energy Astrophysical Phenomena · Physics 2016-03-23 Diego Harari , Silvia Mollerach , Esteban Roulet

In a gravitationally unstable universe, the structure of dark matter and galaxies, intergalactic gas and magnetic field can have severe impact on the propagation of ultra high energy cosmic rays (UHECR) (Ryu & Kang, this proceedings). The…

Astrophysics · Physics 2009-09-25 Jorg P. Rachen

Ultra-high energy cosmic rays can propagate diffusively in cosmic magnetic fields. When their propagation time is comparable to the age of the universe, a suppression in the flux relative to the case in the absence of magnetic fields will…

High Energy Astrophysical Phenomena · Physics 2014-12-10 Rafael Alves Batista , Guenter Sigl

We study the propagation of ultra-high-energy cosmic rays (UHECR) in the Galaxy, concentrating on the energy range below the ankle in the spectrum at 4 EeV. A Monte-Carlo method, based on analytical solutions to the time-dependent diffusion…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Martin Pohl , David Eichler

We discuss the possibility that some recently measured anisotropic cosmic ray components in the TeV-PeV energy range may be an indication of the ejection of a peculiar type of matter. We present a model where a neutron star internal…

High Energy Astrophysical Phenomena · Physics 2014-03-25 M. Angeles Perez-Garcia , K. Kotera , J. Silk