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Very-High-Energy Gamma Rays from a Distant Quasar: How Transparent Is the Universe?

Domenii publicaţii > Fizica + Tipuri publicaţii > Articol în revistã ştiinţificã

Autori: J. Albert et al.

Editorial: Science, 320, p.1752-1755, 2008.

Rezumat:

The atmospheric Cherenkov gamma-ray telescope MAGIC, designed for a low-energy threshold, has detected very-high-energy gamma rays from a giant flare of the distant Quasi-Stellar Radio Source (in short: radio quasar) 3C 279, at a distance of more than 5 billion light-years (a redshift of 0.536). No quasar has been observed previously in very-high-energy gamma radiation, and this is also the most distant object detected emitting gamma rays above 50 gigaelectron volts. Because high-energy gamma rays may be stopped by interacting with the diffuse background light in the universe, the observations by MAGIC imply a low amount for such light, consistent with that known from galaxy counts.

Cuvinte cheie: astrofizica, radiatie gamma, agn // astrophysics, gamma-radiation, agn

URL: http://www.sciencemag.org/cgi/content/full/320/5884/1752?ijkey=HGJBqCL4/TkLM&keytype=ref&siteid=sci