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Cosmic ray propagation is diffusive because of pitch angle scattering by waves. We demonstrate that if the high-amplitude magnetohydrodynamic turbulence with $\tilde B/\langle B\rangle \sim 1$ is present on top of the mean field gradient,…

High Energy Astrophysical Phenomena · Physics 2015-09-30 Mikhail V. Medvedev , Viktor V. Medvedev

We present initial results from our new two-dimensional (radius and latitude), self-consistent model of galactic cosmic rays in the heliosphere. We focus on the latitudinal variations in the solar wind flow caused by the energetic…

Astrophysics · Physics 2009-10-31 V. Florinski , J. R. Jokipii

This paper describes the unfolding of the solar modulated galactic cosmic ray H and He nuclei spectra beyond ~105 AU in the heliosheath. Between 2008.0 and 2012.3 when Voyager 1 went from about 105 to 120.5 AU the spectral intensities of…

Space Physics · Physics 2013-08-09 W. R. Webber , P. R. Higbie , F. B. McDonald

All the current global models of the heliosphere are based on the assumption that the magnetic field in the heliosheath, in the region close to the heliopause is laminar. We argue that in that region the heliospheric magnetic field is not…

Solar and Stellar Astrophysics · Physics 2015-05-27 M. Opher , J. F. Drake , M. Swisdak , K. M. Schoeffler , J. D. Richardson , R. B. Decker , G. Toth

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

The nature of cosmic ray (CR) transport in the Milky Way remains elusive. The predictions of current micro-physical CR transport models in magneto-hydrodynamic (MHD) turbulence are drastically different from what is observed. These models…

The diffusive paradigm for the transport of Galactic cosmic rays is central to our understanding of the origin of these high energy particles. However, it is worth recalling that the normalization, energy dependence, and spatial extent of…

High Energy Astrophysical Phenomena · Physics 2018-07-11 Carmelo Evoli , Pasquale Blasi , Giovanni Morlino , Roberto Aloisio

The misalignment of the solar rotation axis and the magnetic axis of the Sun produces a periodic reversal of the Parker spiral magnetic field and the sectored solar wind. The compression of the sectors is expected to lead to reconnection in…

Space Physics · Physics 2017-03-22 J. F. Drake , M. Swisdak , M. Opher , J. D. Richardson

We expand the off-resonant scattering theory for particle diffusion in magnetized current filaments that can be typically compared to astrophysical jets, including active galactic nucleus jets. In a high plasma beta region where the…

Astrophysics · Physics 2009-11-13 Mitsuru Honda , Yasuko S. Honda

The physical processes involved in diffusion of Galactic cosmic rays in the interstellar medium are addressed. We study the possibility that the nonlinear MHD cascade sets the power-law spectrum of turbulence which scatters charged…

Astrophysics · Physics 2008-11-26 V. S. Ptuskin , I. V. Moskalenko , F. C. Jones , A. W. Strong , V. N. Zirakashvili

The transport of energetic particles such as Cosmic Rays is governed by the properties of the plasma being traversed. While these properties are rather poorly known for galactic and interstellar plasmas due to the lack of in situ…

Solar and Stellar Astrophysics · Physics 2014-06-03 Tobias Wiengarten , Jens Kleimann , Horst Fichtner , Patrick Kühl , Andreas Kopp , Bernd Heber , Ralf Kissmann

Magnetic field fluctuations measured in the heliosheath by the Voyager spacecraft are often characterized as compressible, as indicated by a strong fluctuating component parallel to the mean magnetic field. However, the interpretation of…

Space Physics · Physics 2024-08-01 L. -L. Zhao , G. P. Zank , M. Opher , B. Zieger , H. Li , V. Florinski , L. Adhikari , X. Zhu , M. Nakanotani

Galactic cosmic ray transport relies on the existence of turbulence on scales comparable with the gyration radius of the particles and with wavenumber vector oriented along the local magnetic field. In the standard picture, in which…

High Energy Astrophysical Phenomena · Physics 2023-12-29 O. Pezzi , P. Blasi

Recent advances in understanding of magnetohydrodynamic (MHD) turbulence call for revisions in the picture of cosmic ray transport. In this paper we use recently obtained scaling laws for MHD modes to obtain the scattering frequency for…

Astrophysics · Physics 2007-05-23 Huirong Yan , A. Lazarian

The transport of charged energetic particles in the presence of strong intermittent heliospheric turbulence is computationally analyzed based on known properties of the interplanetary magnetic field and solar wind plasma at 1 Astronomical…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Fathallah Alouani-Bibi , Jakobus A. le Roux

(abridged abstract) Theoretical arguments indicate that close-in terrestial exoplanets may have weak magnetic fields, especially in the case of planets more massive than Earth (super-Earths). Planetary magnetic fields, however, constitute…

Earth and Planetary Astrophysics · Physics 2015-09-03 J. -M. Grießmeier , F. Tabataba-Vakili , A. Stadelmann , J. L. Grenfell , D. Atri

There is currently a controversy as to whether Voyager 1 has already crossed the Termination Shock, the first boundary of the Heliosphere. The region between the Termination Shock and the Heliopause, the Helisheath, is one of the most…

Astrophysics · Physics 2009-11-10 M. Opher , P. C. Liewer , M. Velli , T. I. Gombosi , W. Manchester , D. L. DeZeeuw , G. Toth , I. Sokolov

The transport of cosmic rays through turbulent astrophysical plasmas still constitutes an open problem. Building on recent progress, we study the combined effect of magnetic mirroring and resonant curvature scattering on parallel and…

High Energy Astrophysical Phenomena · Physics 2025-11-25 Jeremiah Lübke , Frederic Effenberger , Mike Wilbert , Horst Fichtner , Rainer Grauer

Cosmic rays are the main agents in controlling the chemical evolution and setting the ambipolar diffusion time of a molecular cloud. We summarise the processes causing the energy degradation of cosmic rays due to their interaction with…

Astrophysics of Galaxies · Physics 2014-06-11 Marco Padovani , Patrick Hennebelle , Daniele Galli

We investigate the anisotropic diffusion of cosmic rays in the large-scale Galactic magnetic field, where diffusion occurs at different rates along and across the magnetic field lines. To model this process, we use stochastic differential…

High Energy Astrophysical Phenomena · Physics 2025-06-17 Ala'a AL-Zetoun