We present a scenario for efficient magnetization of very young galaxies about 0.5 Gigayears after the Big-Bang by a cosmic ray-driven dynamo. These objects experience a phase of strong star formation during this first 10 years. We transfer the knowledge of the connection between star formation and the production rate of cosmic rays by supernova remnants to such high redshift objects. Since the...

It is demonstrated that clusters of galaxies are able to keep cosmic rays for a time exceeding the age of the Universe. This phenomenon reveals itself by the production of the diffuse flux of high energy gamma and neutrino radiation due to the interaction of the cosmic rays with the intracluster gas. The produced flux is determined by the cosmological density of baryons, Ωb, if a large part of ...

We consider the advantages of and the problems associated with hypotheses to explain the origin of ultrahigh energy cosmic rays (UHECR: E > 10 EeV) and the " trans-GZK " cosmic rays (TGZK: E > 100 EeV) both through " old physics " (acceleration in cosmic sources) and " new physics " (new particles, topological defects, fat neutrino cross sections, Lorentz invariance violation).

Interest in extremely high energy cosmic rays has increased rapidly in the last decade. More important perhaps is that that interest now extends well beyond the \usual suspects" to include members of the wider astrophysics and high energy physics communities. Factors which have contributed to this development include: a keener appreciation of the diiculties associated with cosmic ray production...

Star formation and supermassive black hole growth in galaxies appear to be self-limiting. The mechanisms for self-regulation are known as feedback. Cosmic rays, the relativistic particle component of interstellar and intergalactic plasma, are among the agents of feedback. Because cosmic rays are virtually collisionless in the plasma environments of interest, their interaction with the ambient m...

[1] We present a quasi-steady two-dimensional (axisymmetric) model of the heliospheric transport of galactic cosmic rays. The model is based on stochastic simulation techniques and includes all the modulation mechanisms that cosmic rays experience in the heliosphere: convection, adiabatic cooling, diffusion, and drifts. A special emphasis is given to the cosmic ray transport in the vicinity of ...

We consider the recent report that the supernova remnant W49B is a GammaRay Burst (GRB) remnant in our Galaxy. If this is correct, and if GRBs are sources of ultrahigh-energy cosmic rays (UHECRs), a natural consequence of this identification would be a detectable GeV-TeV photon emission around the GRB remnant. The imaging of the surrounding emission could provide new constraints on the jet stru...