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Related papers: A theory of Cosmic Rays

200 papers

We analyse the results of recent measurements of nonthermal emission from individual supernova remnants (SNRs) and their correspondence to the nonlinear kinetic theory of cosmic ray (CR) acceleration in SNRs. It is shown that the theory…

Astrophysics · Physics 2008-11-26 E. G. Berezhko

Cosmic rays (CRs) with ~GeV energies can contribute significantly to the energy and pressure budget in the interstellar, circumgalactic, and intergalactic medium (ISM, CGM, IGM). Recent cosmological simulations have begun to explore these…

Recent observations of cosmic rays (CRs) have revealed a two-component anomaly in the spectra of primary and secondary particles, as well as their ratios, prompting investigation into their common origin. In this study, we incorporate the…

High Energy Astrophysical Phenomena · Physics 2024-03-08 Yu-Hua Yao , Xu-Lin Dong , Yi-Qing Guo , Qiang Yuan

Cosmic rays (CRs) are thought to be an important feedback mechanism in star-forming galaxies. They can provide an important source of pressure support and possibly drive outflows. We perform multidimensional CR-magnetohydrodynamic…

Astrophysics of Galaxies · Physics 2022-03-01 Xiaoshan Huang , Shane W. Davis

Recent accurate measurements of cosmic-ray (CR) protons and nuclei by ATIC-2, CREAM, and PAMELA reveal: a) unexpected spectral hardening in the spectra of CR species above a few hundred GeV per nucleon, b) a harder spectrum of He compared…

High Energy Astrophysical Phenomena · Physics 2016-08-14 Andrey E. Vladimirov , Guðlaugur Jóhannesson , Igor V. Moskalenko , Troy A. Porter

Cosmic ray nuclei, cosmic ray electrons with energy above a few GeV, and the diffuse gamma-ray background radiation (GBR) above a few MeV, presumed to be extragalactic, could all have their origin or residence in our galaxy and its halo.…

Astrophysics · Physics 2007-05-23 Arnon Dar , A. De Rújula , Nikos Antoniou

A complete model for the origin of high-energy >~10^{14} eV) cosmic rays from gamma-ray bursts (GRBs) and implications of this hypothesis are described. Detection of high-energy neutrinos from GRBs provide an unambiguous test of the model.…

Astrophysics · Physics 2010-11-11 C. Dermer

It has recently been shown that the highest energy cosmic rays (CRs) may originate in the same cosmological objects producing $\gamma$-ray bursts. This model requires the presence of intergalactic magnetic fields (IGMF) to delay the arrival…

Astrophysics · Physics 2009-10-28 Eli Waxman , Jordi Miralda-Escude

We investigate the impact of cosmic rays (CRs) on galactic outflows from a multi-phase interstellar medium with solar neighbourhood conditions. The three-dimensional magneto-hydrodynamical simulations include CRs as a relativistic fluid in…

Astrophysics of Galaxies · Physics 2018-07-11 Philipp Girichidis , Thorsten Naab , Michał Hanasz , Stefanie Walch

Cosmic ray (CR) feedback is critical for galaxy formation as CRs drive galactic winds, regularize star formation in galaxies, and escape from active galactic nuclei to heat the cooling cores of galaxy clusters. The feedback strength of CRs…

High Energy Astrophysical Phenomena · Physics 2024-06-10 Rouven Lemmerz , Mohamad Shalaby , Christoph Pfrommer , Timon Thomas

A fundamental problem of cosmic ray (CR) physics is the determination of the average properties of Galactic CRs outside the Solar system. Starting from COS-B data in the 1980's, gamma-ray observations of molecular clouds in the Gould Belt…

High Energy Astrophysical Phenomena · Physics 2015-06-05 M. Kachelriess , S. Ostapchenko

Motivated by the discovery of the non-thermal Fermi bubble features both below and above the Galactic plane, we investigate a scenario in which these bubbles are formed through Galacto-centric outflow. Cosmic rays (CR) both diffusing and…

High Energy Astrophysical Phenomena · Physics 2017-01-11 Andrew M. Taylor , Gwenael Giacinti

Recent observations have revealed that several cosmic ray (CR) sources themselves exhibit pronounced double power-law features in their radiation spectra. Combined with the phenomenon of two-component structure in the observed CR energy…

High Energy Astrophysical Phenomena · Physics 2026-02-10 Lin Nie , Yi-Qing Guo , Si-Ming Liu

We show that the well-known discrepancy between the radial dependence of the Galactic cosmic ray (CR) nucleon distribution, as inferred most recently from EGRET observations of diffuse gamma-rays above 100 MeV, and of the most likely CR…

Astrophysics · Physics 2009-11-07 D. Breitschwerdt , V. A. Dogiel , H. J. Voelk

We investigate the possibility that the cosmic ray (CR) knee is entirely explained by the energy-dependent CR leakage from the Milky Way. We test this hypothesis calculating the trajectories of individual CRs with energies between…

High Energy Astrophysical Phenomena · Physics 2014-08-22 G. Giacinti , M. Kachelriess , D. V. Semikoz

It has been suggested that cosmological gamma-ray bursts (GRBs) can produce the observed flux of cosmic rays at the highest energies. However, recent studies of GRBs indicate that their redshift distribution likely follows that of the…

Astrophysics · Physics 2009-10-31 S. T. Scully , F. W. Stecker

The cosmic ray (CR) energy spectra measured with ATIC, CREAM and PAMELA showed that there is remarkable hardening for rigidity of several hundred GV. We propose that this hardening is due to the superposition of spectra from a population of…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Qiang Yuan , Bing Zhang , Xiao-Jun Bi

We revisit the idea that the Galactic center (GC) is the dominant source of Galactic cosmic rays (GCRs), based on a series of new observational evidence. A unified model is proposed to explain the new phenomena of GCRs and $\gamma$-rays…

High Energy Astrophysical Phenomena · Physics 2013-01-24 Yiqing Guo , Zhaoyang Feng , Qiang Yuan , Cheng Liu , Hongbo Hu

Recent cosmic ray (CR) measurements have revealed unexpected anomalies in secondary CRs, namely deviations from the predictions of the so-called standard Galactic CR paradigm regarding the composition and energy spectra of the products of…

High Energy Astrophysical Phenomena · Physics 2024-10-30 Rui-zhi Yang , Felix Aharonian

Anisotropy is very important to understand cosmic ray (CR) source and interstellar environment. The theoretical explanation of cosmic rays anisotropy from experiments remains challenging and even puzzling for a long time. In this paper, by…

High Energy Astrophysical Phenomena · Physics 2024-07-16 Haoran Meng , Gang Qin