Related papers: On energy equipartition between cosmic rays and ma…
We consider a recently discovered class of instabilities, driven by cosmic ray streaming, in a variety of environments. We show that although these instabilities have been discussed primarily in the context of supernova driven interstellar…
The magnetic fields observed in the Milky~Way and nearby galaxies appear to be in equipartition with the turbulent, thermal, and cosmic ray energy densities, and hence are expected to be dynamically important. However, the origin of these…
After a short introduction on how we get information of the magnetic fields from radio observations I discuss the results concerning the magnetic field structure in galaxies: Large-scale regular magnetic field pattern of spiral structure…
I review what is known and surmised about magnetic fields in space, from our Milky Way environment to the distant Universe beyond the GZK horizon. This includes our gradually improving specification of the CR propagation environment within…
In a previous work we investigated the propagation of fast moving charged particles in a spatially constant but slowly time dependent pseudoscalar background, such as the one provided by cold relic axions. The background induces cosmic rays…
Cosmic rays (CRs) generate diffuse emission while interacting with the Galactic magnetic field (B-field), the interstellar gas and the radiation field. This diffuse emission extends from radio, microwaves, through X-rays, to high-energy…
Context: The relation between Galactic cosmic-ray electrons, magnetic fields and synchrotron radiation. Aims: We exploit synchrotron radiation to constrain the low-energy interstellar electron spectrum, using various radio surveys and…
Total magnetic fields in spiral galaxies, as observed through their total synchrotron emission, are strongest (up to \simeq 30\mu G) in the spiral arms. The degree of radio polarization is low; the field in the arms must be mostly turbulent…
We employ three-dimensional state of the art magnetohydrodynamic models of the early solar wind and heliosphere and a two-dimensional model for cosmic ray transport to investigate the cosmic ray spectrum and flux near the Archean Earth. We…
Cosmic rays have been shown to be extremely important in the dynamics of diffuse gas in galaxies, helping to maintain hydrostatic equilibrium, and serving as a regulating force in star formation. In this paper, we address the influence of…
We improve on the model of the Galactic Magnetic Field (GMF) from Jansson \& Farrar (2012), which was constrained using all-sky rotation measures of extragalactic sources and polarized and unpolarized synchrotron emission data from WMAP. We…
Cosmic rays (CRs) are dynamically important for the formation and evolution of galaxies by regulating star formation and by powering galactic outflows. However, to what extent CRs regulate galaxy formation depends on the coupling strength…
The physics of energetic particle propagation in magnetised environments plays a crucial role in both the processes of acceleration and transport of cosmic rays. Recent theoretical developments in the field of cosmic ray research have been…
The possibility that the magnetic field is strongly correlated with the large-scale structure of the universe has been recently proposed in the literature. In this scenario the intergalactic magnetic field has a strong (m Gauss) regular…
We present the results of a study that simulates trajectories of ultra-high energy cosmic rays from Centaurus A to Earth, for particle rigidities from $E/Z = 2$ EV to 100 EV, i.e., covering the possibility of primary particles as heavy as…
Our knowledge of the mass composition of cosmic rays is deficient at all energies above 10^17. Here systematic differences between different measurements are discussed and, in particular, it is argued that there is no compelling evidence to…
We present a parameter study of the magnetohydrodynamical dynamo driven by cosmic rays in the interstellar medium (ISM) focusing on the efficiency of magnetic field amplification and the issue of energy equipartition between magnetic,…
Cosmic rays are a fundamental source of ionization for molecular and diffuse clouds, influencing their chemical, thermal, and dynamical evolution. The amount of cosmic rays inside a cloud also determines the $\gamma$-ray flux produced by…
We study the influence of the random part of the Galactic magnetic field on the propagation of ultra high-energy cosmic rays. Within very mild approximations about the properties of the electron density fluctuations in the Galaxy we are…
We study the effects that the diffusion of the cosmic rays in the magnetic field of the Local Supercluster can have on the spectrum of a nearby extragalactic source at ultrahigh energies. We find that the strong enhancement of the flux…