2006/12/01 by HESS Collaboration, F. A. Aharonian · 1 citation
Physics and Astronomy · #astro-ph
paper · pdf · doi:10.1126/science.1134408
published as Science314:1424,2006 · 16 pages, 5 figures, published in Science
arxiv created 2006/12/01 · arxiv updated 2009/12/01
The detection of fast variations of the TeV (1012 eV) gamma-ray flux, on time-scales of days, from the nearby radio galaxy M 87 is reported. These variations are ~10 times faster than that observed in any other waveband and imply a very compact emission region with a dimension similar to the Schwarzschild radius of the central black hole. We thus can exclude several other sites and processes of the gamma-ray production. The observations confirm that TeV gamma-rays are emitted by extragalactic sources other than blazars, where jets are not relativistically beamed towards the observer.