Related papers: Cosmic-ray diffusion in a sectored magnetic field …
We discuss two extraordinary increases of cosmic ray intensity observed by Voyager 1 in the last 1.1 AU before heliopause crossing, Aug 2012 at 121.7 AU. The two increases are roughly similar in amplitude and result in a total increase of…
We study processes related to magnetic reconnection and plasma turbulence occurring in the presence of the heliopause (HP) and the heliospheric current sheet. It is shown that the interaction of plasmoids initiated by magnetic reconnection…
Turbulence is believed to play important roles in the origin of cosmic magnetism. While it is well known that turbulence can efficiently amplify a uniform or spatially homogeneous seed magnetic field, it is not clear whether or not we can…
We argue that the diffusion of cosmic rays in the Galactic magnetic field has to be strongly anisotropic. As a result, the number of CR sources contributing to the local CR flux is reduced by a factor $\sim 200$. The CR density is therefore…
We have determined the solar modulation potential, phi, vs. time that is observed at Voyager 1 and 2 from measurements of the H and He nuclei intensities at a common energy of 250 MeVnuc. The H nuclei have a rigidity 0.7 GV, the He nuclei…
In August of 2012 the Voyager 1 space probe entered a distinctly new region of space characterized by a virtual absence of heliospheric energetic charged particles and magnetic fluctuations, dubbed a "magnetic highway". Prior to their…
Diffuse interstellar clouds show large abundances of H_3^+ which can be maintained only by a high ionization rate of H_2. Cosmic rays are the dominant ionization mechanism in this environment, so the large ionization rate implies a high…
Cosmic ray propagation is determined by the properties of interstellar turbulence. The multiphase nature of interstellar medium (ISM) and diversity of driving mechanisms give rise to spatial variation of turbulence properties. Meanwhile,…
In this paper, we investigate the heliospheric modulation of cosmic rays in interplanetary space, focusing on their propagation times and energy losses over the solar cycle. To perform the calculations, we employed a data-driven model based…
Convection is ubiquitous in stellar and planetary interiors where it likely plays an integral role in the generation of magnetic fields. As the interiors of these objects remain hidden from direct observation, numerical models of convection…
Recent direct measurements of Galactic cosmic ray spectra by balloon/space-borne detectors reveal spectral hardenings of all major nucleus species at rigidities of a few hundred GV. The all-sky diffuse gamma-ray emissions measured by the…
In the subset of luminous, early-type stars with strong, large-scale magnetic fields and moderate to rapid rotation, material from the star's radiatively driven stellar wind outflow becomes trapped by closed magnetic loops, forming a…
Cosmic rays are able to heat interstellar dust grains. This may enhance molecule mobility in icy mantles that have accumulated on the grains in dark cloud cores. A three-phase astrochemical model was used to investigate the molecule…
One of the unsolved problems in cosmic ray (CR) physics is the small radial gradient of the gamma-ray intensity compared to the inferred CR source distribution in the Galactic disk. In diffusive CR propagation models the most natural…
Cosmic ray (CR) transport and acceleration is essential for many astrophysical problems, e.g., CMB foreground, ionization of molecular clouds and all high energy phenomena. Recent advances in MHD turbulence call for revisions in the…
The possibility that the magnetic field is strongly correlated with the large-scale structure of the universe has been recently considered in the literature. In this scenario the intergalactic magnetic field has a strong ($\mu$G) regular…
Studies on Voyager 1 using the CRS instrument have shown the presence of sub-MeV electrons in the interstellar medium beyond the heliopause. We believe that these electrons are the very low energy tail of the distribution of galactic GeV…
A correct description of cosmic-ray (CR) diffusion in turbulent plasma is essential for many astrophysical and heliospheric problems. This paper aims to present physical diffusion behavior of CRs in actual turbulent magnetic fields, model…
Radio, X-ray and infrared observations of the inner few hundred pc of the Galactic center have highlighted two characteristics to the ISM. The cosmic ray ionization rate derived from molecular ions such as H$^+_3$, is at least two to three…
Observations of the vicinity of a variety of galactic gamma-ray sources have indicated a local suppression of diffusivity of cosmic rays by up to three orders of magnitude. However, the impact of these low-diffusion zones on \emph{global}…