1994•The Astrophysical JournalRequires access
Search for ultra-high energy radiation from gamma-ray bursts
D. E. Alexandreas, G. E. Allen, D. Berley, S. Biller, R. L. Burman, M. Cavalli-Sforza, C. Y. Chang, M. L. Chen, P. Chumney, D. G. Coyne, C. Dion, G. M. Dion, D. E. Dorfan, R. W. Ellsworth, J. A. Goodman, T. J. Haines, M. Harmon, C. M. Hoffman, L Kelley, S. Klein, D. E. Nagle, Susanne Schaller, D. Schmidt, R. W. Schnee, A. Shoup, G. Sinnis, M. J. Stark, D. D. Weeks, D. A. Williams, J. Wu, T. Yang, G. B. Yodh, W. Zhang
Open publisher page 12 citations
Abstract
A recent class of models suggests that some gamma-ray bursters may produce ultra-high-energy (>~100 TeV) photons. Using data from the CYGNUS array, we have searched for evidence of emission of ultra-high-energy radiation coincident with gamma-ray bursts observed either by the third Interplanetary Network of satellites or by the BATSE instrument on the Compton Gamma-Ray Observatory. No statistically significant excess was found for six bursts whose locations were accurately determined by the Network, or for any point in the sky within 2 σ of the BATSE location coordinates of 52 additional bursts. Flux upper limits depend greatly on the zenith angles of the bursts, but typical limits above 100 TeV are ~4 x 10^-10^ cm^-2^ s^-1^. The flux upper limits for three of the bursts imply that the observed spectrum softens between 2 MeV and ~100 TeV: If the production spectrum does not soften between these energies, the bursts must have a cosmological origin.