Milagro Observation of a Localized Excess of $\sim10$ TeV Cosmic Rays

A analysis of Milagro data shows two regions in the Northern Sky of excess cosmic rays on an angular scale of $\sim10^\circ$ with greater than $12\sigma$ significance. Diagnostics show that both regions are inconsistent with gamma-ray emission at a confidence level of $>11\sigma$. One of the regions has a different energy spectrum than the cosmic-ray background at a confidence level of $4.6\sigma$, and it is consistent with a hard spectrum with an exponential cutoff, with the most significant excess at $\sim10$ TeV. This is difficult to explain since a 10 TeV proton in a 1 $\mu$G field has a gyroradius of 0.01 pc.