Observation of a Very Energetic Cosmic Ray Well Beyond the Predicted 2.7 K Cutoff in the Primary Energy Spectrum.
نویسندگان
چکیده
A very energetic cosmic ray of energy about (1.72.6)10 20 eV was observed by the Akeno Giant Air Shower Array (AGASA) on December 3, 1993 from the direction of galactic longitude l=131 and galactic latitude b=-41 within an error circle of 1.0 radius. Shower characteristics such as lateral distribution and arrival time spread of charged particles, and lateral distribution of muons (0.5GeV) are well tted to values extrapolated from lower energy showers. If this cosmic ray were a proton, its origin could be extragalac-tic. However, the distance of the source cannot be much more than a few times 10 Mpc due to the energy loss during its travel from interactions with universal background radiation. There is no known active object within 50 Mpc near the arrival direction of this shower.
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ورودعنوان ژورنال:
- Physical review letters
دوره 73 26 شماره
صفحات -
تاریخ انتشار 1994