Gary Liu

The macro detector at the Gran Sasso Laboratory

Abstract The MACRO detector is presently under construction, its installation at Gran Sasso being planned to start in September 1987. It is a large area detector, the acceptance for isotropic particle fluxes being around 10 000 m 2 sr, designed to search for rare phenomena in the cosmic radiation. It makes use of three detection techniques: liquid scintillator counters, plastic streamer tubes, and track-etch. It will perform a search for GUT monopoles (or any supermassive charged penetrating particle), a survey of cosmic point sources of HE gammas and neutrinos, a systematic study of the penetrating cosmic ray muons, and will be sensitive to neutrino bursts from gravitational stellar collapses in the Galaxy.

Study of penetrating cosmic ray muons and search for large scale anisotropies at the Gran Sasso Laboratory

Abstract The MACRO detector, located in the underground Gran Sasso Laboratory, had its initial data run from February 27 to May 30, 1989, using the first supermodule (SΩ∼800 m 2 sr ) . Approximately 245 000 muon events were recorded. Here are reported the results of the analysis of penetrating muons which determine the measured vertical muon flux at depths greater than 3000 m.w.e. In addition the data have been used to search for large scale anisotropies.