Cosmic rays are the highest-energy particles found in nature. Measurements of the mass composition of cosmic rays with energies of 1017–1018 electronvolts are essential to understanding whether they have galactic or extragalactic sources. It has also been proposed that the astrophysical neutrino signal comes from accelerators capable of producing cosmic rays of these energies. Cosmic rays initiate air showers—cascades of secondary particles in the...
Tag Archives: cosmic
Space science: Cosmic rays beyond the knees
The development of a radio technique for detecting cosmic rays casts fresh light on the origins of some of these accelerated particles, and suggests that they might have travelled much farther than was previously thought. See Letter p.70
Nature 531 43 doi: 10.1038/531043a
Hubble Space Telescope salutes ‘Star Wars: The Force Awakens’ with cosmic lightsaber
Leave it to the scientists behind the Hubble Space Telescope to capitalize on the craziness over “Star...
Warm–hot baryons comprise 5–10 per cent of filaments in the cosmic web
Observations of the cosmic microwave background indicate that baryons account for 5 per cent of the Universe’s total energy content. In the local Universe, the census of all observed baryons falls short of this estimate by a factor of two. Cosmological simulations indicate that the missing baryons have not condensed into virialized haloes, but reside throughout the filaments of the cosmic web (where matter...
Warm–hot baryons comprise 5–10 per cent of filaments in the cosmic web
Observations of the cosmic microwave background indicate that baryons account for 5 per cent of the Universe’s total energy content. In the local Universe, the census of all observed baryons falls short of this estimate by a factor of two. Cosmological simulations indicate that the missing baryons have not condensed into virialized haloes, but reside throughout the filaments of the cosmic web (where matter...