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Evidence for new unidentified TeV gamma-ray sources from angularly-correlated hot-spots observed by independent TeV gamma-ray sky surveys

G. Walker·R. Atkins·D. Kieda
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Abstract

We have examined the directional cross-correlation of statistical `hot-spots' between a Northern Sky TeV Gamma Ray Survey by the Milagro Observatory and a similar survey by the Tibet Array. We find the directions of these hot-spots are angularly uncorrelated between the two surveys for large angular separations (Delta theta > 4 degrees), but there appears to be a statistically significant correlation between hot-spot directions for Delta theta < 1.5 degrees. Independent simulations indicate the chance probability for the occurrence of this correlation is approximately 10^-4, implying the existence of one or more previously unobserved TeV gamma-ray sources in these directions. The data sets are consistent with both point-like sources or diffuse sources with extent of 1 - 2 degrees.

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G. Walker, R. Atkins, D. Kieda. 2004-08-31. Evidence for new unidentified TeV gamma-ray sources from angularly-correlated hot-spots observed by independent TeV gamma-ray sky surveys. https://doi.org/10.1086/425863

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