Record-breaking gamma ray is smoking gun for Milky Way cosmic rays – Physics World – physicsworld.com
An image of the Milky Way. The yellow dots represent the points of origin of ultrahigh-energy gamma rays. The light shaded areas are regions unobservable from Tibet. (Courtesy: NASA/Tibet AS Collaboration)
The most energetic gamma ray ever seen could be the strongest evidence yet that high-energy cosmic rays are produced within our Milky Way galaxy, where they spend millions of years accumulating, forming a cosmic-ray pool.
The origin of cosmic rays is one of the most enduring mysteries in astrophysics….