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Search for Correlated High Energy Cosmic Ray Events with CHICOS

B. E. Carlson·E. Brobeck·C. J. Jillings·M. B. Larson·T. W. Lynn·R. D. McKeown·James E. Hill·B. Falkowski·R. Seki·J. Sepikas·G. B. Yodh
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Abstract

We present the results of a search for time correlations in high energy cosmic ray data (primary E > 10^{14} eV) collected by the California HIgh school Cosmic ray ObServatory (CHICOS) array. Data from 60 detector sites spread over an area of 400 km^2 were studied for evidence of correlated events separated by more than 1 km with coincidence times ranging from 1 microsec up to 1 second. All searches were consistent with the absence of excess coincidences except for a 2.9 sigma excess observed for coincidence times less than 10 microsec. We report upper limits for the coincidence probability as a function of coincidence time.

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B. E. Carlson, E. Brobeck, C. J. Jillings, M. B. Larson, T. W. Lynn, R. D. McKeown, James E. Hill, B. Falkowski, R. Seki, J. Sepikas, G. B. Yodh. 2005-02-15. Search for Correlated High Energy Cosmic Ray Events with CHICOS. https://doi.org/10.1088/0954-3899%2F31%2F5%2F011

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