A search for cosmic gamma-ray bursts in the GeV energy range has been performed by means of the EAS-TOP Extensive Air Shower array at Campo Imperatore (Gran Sasso Laboratories) during the period March-December 1990. In 2566.5 hours of measurement the obtained upper limit to the rate of bursts of amplitude >2% of the cosmic-ray intensity and time duration τ=1 s, is R≤7.9y-1 (90% c.l.). Assuming for γ-rays a differential energy spectrum S(E 0 )≈E 0 -2.5, the corresponding upper limit to the energy flux of γ-rays with energy >5 GeV in bursts of duration τ≤1 s is Φ<8.3·10-5erg cm-2.
- Cosmic-ray interactions with the Earth
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Physics and Astronomy (miscellaneous)