Surveying the TeV Sky with Milagro Available to Purchase

A wide field of view, high duty factor, TeV gamma‐ray observatory is essential for studying TeV astrophysical sources, because most of these sources are either highly variable or are extended. Milagro is such a TeV detector and has performed the deepest survey of the Northern Hemisphere sky. In addition to detecting the known TeV sources of the Crab Nebula and Markarian 421, Milagro has made the first detection of diffuse TeV emission from the Galactic plane. The Milagro data has been searched for unknown point sources and extended sources. Evidence for a new extended TeV source is seen and is coincident with an EGRET unidentified source. The Milagro data has also been searched for the predicted TeV emitters of gamma‐ray bursts, galaxy clusters, and EGRET unidentified sources. Based on the success of Milagro, a second generation water Cherenkov gamma‐ray observatory is planned which will give an increase in sensitivity of more than an order of magnitude.