Sources of Cosmic Gamma Rays

Measurements of the bremsstrahlung continuum during solar flares indicate that relativistic electrons are a 

FIGURE 4 The gamma-ray spectrum of the June 4, 1991, solar flare obtained with the OSSE instrument aboard the Compton Gamma Ray Observatory. Prominent gamma-ray emission lines are identified, along with the primary processes responsible for both the observed line and continuum emission. (Courtesy NASA and the CGRO OSSE Instrument Team (G. H. Share and R. J. Murphy.)) 

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