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Limits on Very High Energy Emission from Gamma-Ray Bursts with the Milagro Observatory

The Milagro Collaboration·R. Atkins·W. Benbow·D. Berley·E. Blaufuss·J. Bussons·D. G. Coyne·T. DeYoung·B. L. Dingus·D. E. Dorfan·R. W. Ellsworth·L. Fleysher·R. Fleysher·G. Gisler·M. M. Gonzalez·J. A. Goodman·T. J. Haines·E. Hays·C. M. Hoffman·L. A. Kelley·J. E. McEnery·R. S. Miller·A. I. Mincer·M. F. Morales·P. Nemethy·D. Noyes·J. M. Ryan·F. W. Samuelson·A. Shoup·G. Sinnis·A. J. Smith·G. W. Sullivan·D. A. Williams·S. Westerhoff·M. E. Wilson·X. Xu·G. B. Yodh
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Abstract

The Milagro telescope monitors the northern sky for 100 GeV to 100 TeV transient emission through continuous very high energy wide-field observations. The large effective area and ~100 GeV energy threshold of Milagro allow it to detect very high energy (VHE) gamma-ray burst emission with much higher sensitivity than previous instruments and a fluence sensitivity at VHE energies comparable to that of dedicated gamma-ray burst satellites at keV to MeV energies. Even in the absence of a positive detection, VHE observations can place important constraints on gamma-ray burst (GRB) progenitor and emission models. We present limits on the VHE flux of 40 s -- 3 h duration transients nearby to earth, as well as sensitivity distributions which have been corrected for gamma-ray absorption by extragalactic background light and cosmological effects. The sensitivity distributions suggest that the typical intrinsic VHE fluence of GRBs is similar or weaker than the keV -- MeV emission, and we demonstrate how these sensitivity distributions may be used to place observational constraints on the absolute VHE luminosity of gamma-ray bursts for any GRB emission and progenitor model.

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The Milagro Collaboration, R. Atkins, W. Benbow, D. Berley, E. Blaufuss, J. Bussons, D. G. Coyne, T. DeYoung, B. L. Dingus, D. E. Dorfan, R. W. Ellsworth, L. Fleysher, R. Fleysher, G. Gisler, M. M. Gonzalez, J. A. Goodman, T. J. Haines, E. Hays, C. M. Hoffman, L. A. Kelley, J. E. McEnery, R. S. Miller, A. I. Mincer, M. F. Morales, P. Nemethy, D. Noyes, J. M. Ryan, F. W. Samuelson, A. Shoup, G. Sinnis, A. J. Smith, G. W. Sullivan, D. A. Williams, S. Westerhoff, M. E. Wilson, X. Xu, G. B. Yodh. 2004-02-06. Limits on Very High Energy Emission from Gamma-Ray Bursts with the Milagro Observatory. https://doi.org/10.1086/383414

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