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We model the transport of cosmic ray nuclei in the Galaxy by means of a new numerical code. Differently from previous numerical models we account for a generic spatial distribution of the diffusion coefficient. We found that in the case of…

Astrophysics · Physics 2016-05-19 C. Evoli , D. Gaggero , D. Grasso , L. Maccione

Spectra of Galactic Cosmic Rays (GCRs) measured at the Earth are the combination of several processes: sources production and acceleration, propagation in the interstellar medium and propagation in the heliosphere. Inside the solar cavity…

Earth and Planetary Astrophysics · Physics 2017-08-23 P. Bobik , G. Boella , M. J. Boschini , C. Consolandi , S. Della Torre , M. Gervasi , D. Grandi , K. Kudela , E. Memola , S. Pensotti , P. G. Rancoita , M. Tacconi

We analyze the three dimensional anisotropy of the galactic cosmic ray (GCR) intensities observed independently with a muon detector at Nagoya in Japan and neutron monitors over four solar activity cycles. We clearly see the phase of the…

Solar and Stellar Astrophysics · Physics 2020-12-29 K. Munakata , M. Kozai , C. Kato , J. Kota

We show that the higher range of the heliolongitudinal asymmetry of the solar wind speed in the positive polarity period (Apos) than in the negative polarity period (Aneg) is one of the important reasons of the larger amplitudes of the…

Solar and Stellar Astrophysics · Physics 2015-04-07 R. Modzelewska , M. V. Alania

The transport environment for particles in the heliosphere, e.g. galactic cosmic rays (GCRs) and MeV electrons (including those originating from Jupiters magnetosphere), is defined by the solar wind flow and the structure of the embedded…

High Energy Astrophysical Phenomena · Physics 2013-09-06 P. Kühl , N. Dresing , P. Dunzlaff , H. Fichtner , J. Gieseler , R. Gómez-Herrero , B. Heber , A. Klassen , J. Kleimann , A. Kopp , M. Potgieter , K. Scherer , R. D. Strauss

We study the time-dependent modulation effect and derive the local interstellar spectra (LIS) for the cosmic ray (CR) proton, helium, boron and carbon. A two-dimensional modulation model including the variation of the interplanetary…

High Energy Astrophysical Phenomena · Physics 2019-09-25 Bing-Bing Wang , Xiao-Jun Bi , Kung Fang , Su-Jie Lin , Peng-Fei Yin

We construct a Galactic cosmic ray (CR) diffusion model while considering that CR sources reside predominantly in the Galactic spiral arms. We find that the CR flux (CRF) reaching the solar system should periodically increase each crossing…

Astrophysics · Physics 2008-11-26 Nir J. Shaviv

Recent observations by the H.E.S.S. collaboration of the Galactic Centre region have revealed what appears to be gamma-ray emission from the decay of pions produced by interactions of recently accelerated cosmic rays with local molecular…

Astrophysics · Physics 2009-11-13 Stavros Dimitrakoudis , Apostolos Mastichiadis , Athanasios Geranios

The spectrum and morphology of the diffuse Galactic gamma-ray emission carries valuable information on cosmic ray (CR) propagation. Recent results obtained by analyzing Fermi-LAT data accumulated over seven years of observation show a…

High Energy Astrophysical Phenomena · Physics 2016-08-05 S. Recchia , P. Blasi , G. Morlino

Recent precise measurements of cosmic ray spectral revealed an anomalous hardening at ~200 GV for nuclei from PAMELA, CREAM, ATIC, AMS02 experiments and at tens of GeV for primary electron derived from AMS02 experiment. Particularly, the…

High Energy Astrophysical Phenomena · Physics 2018-04-11 Yi-Qing Guo , Zhen Tian , Chao Jin

Galactic cosmic rays are energetic particles important in the context of life. Many works have investigated the propagation of Galactic cosmic rays through the Sun's heliosphere. However, the cosmic ray fluxes in M dwarf systems are still…

Solar and Stellar Astrophysics · Physics 2021-06-09 A. L. Mesquita , D. Rodgers-Lee , A. A. Vidotto

We revisit propagation of galactic cosmic rays (CRs) in light of recent advances in CR diffusion theory in realistic interstellar turbulence. We use a tested model of turbulence in which it has been shown that fast modes dominate scattering…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Carmelo Evoli , Huirong Yan

(abridged) Within nearby galaxies, variations in the radio-FIR correlation have been observed, mainly because the cosmic ray electrons migrate before they lose their energy via synchrotron emission or escape. The major cosmic ray electron…

Astrophysics of Galaxies · Physics 2020-02-05 B. Vollmer , M. Soida , R. Beck , M. Powalka

We study features of the 3D anisotropy of galactic cosmic rays (GCR) for 1965-2014. We analyze the 27-day variations of the 2D GCR anisotropy in the ecliptic plane, and the north-south anisotropy normal to the ecliptic plane. We study the…

Solar and Stellar Astrophysics · Physics 2021-04-26 R. Modzelewska , M. V. Alania

Cosmic rays (CR), both solar and Galactic, have an ionising effect on the Earth's atmosphere and are thought to be important for prebiotic molecule production. In particular, the $\rm{H_2}$-dominated atmosphere following an ocean-vaporising…

Earth and Planetary Astrophysics · Physics 2025-05-07 S. R. Raeside , D. Rodgers-Lee , P. B. Rimmer

More and more observations have indicated the existence of slow diffusion phenomena in astrophysical environments, such as around the supernova remnants and pulsar $\gamma$-ray halos, where the diffusion coefficient of cosmic rays (CRs)…

High Energy Astrophysical Phenomena · Physics 2025-06-24 Yawen Xiao , Jianfu Zhang , Siyao Xu

We introduce a static toy model of the cosmic ray (CR) universe in which cosmic ray propagation is taken to be diffusive and cosmic ray sources are distributed randomly with a density the same as that of local L* galaxies, $5 \times…

Astrophysics · Physics 2007-10-29 Roger Clay , Roland M. Crocker

We present an analysis of the time-dependent modulation of galactic cosmic rays near Earth, with a focus on the cosmic proton flux and polar field. Using data from the Alpha Magnetic Spectrometer (AMS) and the Wilcox Solar Observatory, we…

Solar and Stellar Astrophysics · Physics 2025-04-30 Shaokun Gong , Linjing Duan , Jiawei Zhao , Xueyu Wei , Jie Feng , Zhibing Li

An extensive program for the calculation of galactic cosmic-ray propagation has been developed. Primary and secondary nucleons, primary and secondary electrons, and secondary positrons are included. The basic spatial propagation mechanisms…

Astrophysics · Physics 2008-02-03 A. W. Strong , I. V. Moskalenko , V. Schoenfelder

During the transition from solar cycle 23 to 24 from 2006 to 2009, the Sun was in an unusual solar minimum with very low activity over a long period. These exceptional conditions included a very low interplanetary magnetic field (IMF)…

High Energy Astrophysical Phenomena · Physics 2017-11-28 Jan Gieseler , Bernd Heber