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Gamma-ray Detectors

Explorer 11 was the first gamma-ray detection satellite flown, weighing in at 82 pounds. It was launched on 27 April 1961 and the instrument aboard was designed to detect gamma-rays above 50 MeV.

Over a period of 23 days, 9 hours of data from "pointing into space" was obtained. In this data were found 22 events from gamma-rays and 22,000 events due to charged cosmic rays.

Imagine the Universe is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center.

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