Evidence for the possible existence of a strong flux of low-energy (< 10 MeV) cosmic ray electrons in the Galaxy has been recently established by GINGA, OSSE and COMPTEL observations of the diffuse galactic gamma ray continuum emission down to photon energies below 50 keV. We explain the implied presence of many low-energy cosmic ray electrons with the existence of interstellar in-situ reaccele...

We suggest that the highest energy > ∼ 10eV cosmic ray primaries may be relativistic magnetic monopoles. Motivations for this hypothesis are that conventional primaries are problematic, while monopoles are naturally accelerated to E ∼ 10eV by galactic magnetic fields. By matching the cosmic monopole production mechanism to the observed highest energy cosmic ray flux we estimate the monopole mas...

RXTE, GINGA, and OSSE observations have revealed an intense low-energy γ-ray continuum emission from the Galactic plane, which is commonly interpreted as evidence for the possible existence of a strong flux of low-energy cosmic ray electrons. In this Paper I discuss the scenario of a hadronic origin of the soft Galactic γ-ray continuum through inverse bremsstrahlung. A flux of low-energy cosmic...

A new, unique mechanism accounting for the knee and the ankle in the energy spectrum of the cosmic radiation is presented. The interplay of the form and strength of the galactic magnetic field, the rising trend of the nuclear cross sections with energy, the position of the solar cavity within the Galaxy and disc size generates knees and ankles of individual ions. The influence of these observat...

There is evidence that cosmic rays were present in galaxies at moderately high redshift. This suggests that magnetic fields were also present. If cosmic rays and magnetic fields must always be close to equipartition, as they are to an order of magnitude within the local universe, this would provide a powerful constraint on theories of the origin and evolution of magnetic fields in galaxies. We ...

The general features of the cosmic-ray spectrum have been known for a long time. Although the basic approaches to understanding cosmic-ray propagation and acceleration have also been well understood for many years, there are several questions of great interest that motivate the current intense experimental activity in the field. If the energy-dependence of the secondary to primary ratio of gala...

Cosmic ray events beyond the Greisen-Zatsepin-Kuzmin cutoff represent a great challenge for particle physics and cosmology. We show that the physics of heavy Majorana neutrinos, well defined by their masses, cross sections and lifetimes, could explain the highest energy cosmic rays as a consequence of the galactic annihilation of heavy neutrinos as cold dark matter particles. Galactic nuclei ac...

We report high-resolution observations made in interplanetary space of 83-284 MeV per nucleon galactic cosmic-ray iron isotopes and directly establish that 56Fe is the dominant cosmic-ray Fe isotope. We find the following percentage abundances for Fe at the cosmic-ray source: 54Fe = 9(+8, -5)%, 55Fe:::; 7%, 56Fe = 91(+5, -11)%, 57Fe:::; 8%, and 58Fe:::; 6%. When compared to calculated nucleosyn...