Search for ultra-high-energy radiation from gamma-ray bursts
Abstract
Using data from the CYGNUS extensive air shower array, we have searched for evidence of the emission of ultra-high-energy radiation coincident with gamma-ray bursts observed by the BATSE instrument on the Compton Gamma-Ray Observatory. No statistically significant excess was found for any point in the sky within 4(sigma) of BATSE's best location coordinates for any of the 56 bursts examined. Furthermore, no events were seen in the 2.2 deg radius circular bin surrounding gamma-ray burst GRB 920720, whose location was determined accurately by the Compton/Ulysses/PVO Interplanetary Network of satellites. Flux upper limits depend greatly on the actual zenith angle of the burst. Typical fluence upper limits above 100 TeV are approximately 10-6 erg/sq cm. The fluence upper limits for GRB 920720 is 2(10)-6 erg/sq cm.
- Publication:
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Presented at the International Cosmic-Ray Conference
- Pub Date:
- 1993
- Bibcode:
- 1993icr..confS..19S
- Keywords:
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- Cosmic Ray Showers;
- Fluence;
- Gamma Ray Bursts;
- Gamma Rays;
- Observatories;
- Monte Carlo Method;
- Radiation Counters;
- Zenith;
- Space Radiation