Related papers: Cosmic-Ray Convection-Diffusion Anisotropy
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…
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…
The inverse Compton scattering of interstellar photons off cosmic-ray electrons seems to play a more important role in the generation of diffuse emission from the Galaxy than thought before. The background radiation field of the Galaxy is…
In classical diffusion, particle step-sizes have a Gaussian distribution. However, in superdiffusion, they have power-law tails, with transport dominated by rare, long L\'evy flights. Similarly, if the time interval between scattering…
Simulations of the cosmic-ray (CR) anisotropy down to TeV energies are presented, using turbulence parameters consistent with those inferred from observations of the interstellar medium. We compute the angular power spectra $C_{\ell}$ of…
Modern X-ray and $\gamma$-ray instruments are revealing a growing class of Galactic non-thermal sources whose emission centroids are measurably offset from the nearest plausible sites of cosmic ray (CR) acceleration. Such "displaced"…
We consider the release and subsequent gravity-driven spreading of a finite volume of fluid in an anisotropic porous medium bounded by an impermeable substrate. When the permeability in the vertical direction is much smaller than the…
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…
An intermediate-scale energy spectrum anisotropy has been found in the arrival directions of ultra-high energy cosmic rays of energies above $10^{19.2}$ eV in the northern hemisphere, using 7 years of data from the Telescope Array surface…
The physics of Cosmic ray (CR) transport remains a key uncertainty in assessing whether CRs can produce galaxy-scale outflows consistent with observations. In this paper, we elucidate the physics of CR-driven galactic winds for CR transport…
The IceCube Neutrino Observatory has accumulated a total of 318 billion cosmic-ray induced muon events between May 2009 and May 2015. This data set was used for a detailed analysis of the cosmic-ray arrival direction anisotropy in the TeV…
We investigate the production of cosmic ray (CR) protons at cosmological shocks by performing, for the first time, numerical simulations of large scale structure formation that include directly the acceleration, transport and energy losses…
In this paper we report the first observation in the Southern hemisphere of an energy dependence in the Galactic cosmic ray anisotropy up to a few hundred TeV. This measurement was performed using cosmic ray induced muons recorded by the…
We numerically study the diffusion and scattering of cosmic rays (CRs) together with their acceleration processes in the framework of the modern understanding of magnetohydrodynamic (MHD) turbulence. Based on the properties of compressible…
Cosmic rays propagate through the Galaxy and encounter systems that may trap them temporarily, as well as magnetic field structures that induce chaotic behavior on their trajectories. In particular, this is the case for particles that…
Cosmic rays (CRs) may drive outflows and alter the phase structure of the circumgalactic medium, with potentially important implications on galaxy formation. However, these effects ultimately depend on the dominant mode of transport of CRs…
This study investigates Parker instability in an interstellar medium (ISM) near the Galactic plane using three-dimensional magneto-hydrodynamic simulations. Parker instability arises from the presence of a magnetic field in a plasma,…
Anomalous transport processes in which the variance of the distance travelled does not necessarily increase linearly with time are modelled using the formalism of continuous time random walks. We compute particle propagators which have the…
During the past two decades, experiments in both the Northern and Southern hemispheres have observed a small but measurable energy-dependent sidereal anisotropy in the arrival direction distribution of galactic cosmic rays. The relative…
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…