Journal ArticleFrom April 1988 to February 1990 we used a two-level array of scintillators to search in the cosmic radiation for compact sources of y rays above 200 TeV. Counters on the surface measured the size and direction of extensive air showers while counters buried 3 m below ground measured their muon content. Showers induced by y rays are expected to have many fewer muons than those initiated by hadrons so the selection of muon-poor showers should greatly reduce the background of hadronic showers. Three objects, Cygnus X-3, the Crab nebula, and Hercules X-l, were examined in detail. Searches were made on short and long time scales and source periodicity was used, where applicable, to enhance any possible signals. We found no evidence for any compact sources
