The High-Altitude Water Cherenkov (HAWC) observatory in Mexico: The primary detector

The High-Altitude Water Cherenkov (HAWC) observatory is a second-generation continuously operated, wide field-of-view, TeV gamma-ray observatory. The HAWC observatory and its analysis techniques build on experience of the Milagro experiment in using ground-based water Cherenkov detectors for gamma-ray astronomy. HAWC is located on the Sierra Negra volcano in Mexico at an elevation of 4100 meters above sea level. The completed HAWC observatory principal detector (HAWC) consists of 300 closely spaced water Cherenkov detectors, each equipped with four photomultiplier tubes to provide timing and charge information to reconstruct the extensive air shower energy and arrival direction. The HAWC observatory has been optimized to observe transient and steady emission from sources of gamma rays within an energy range from several hundred GeV to several hundred TeV. However, most of the air showers detected are initiated by cosmic rays, allowing studies of cosmic rays also to be performed. This paper describes the characteristics of the HAWC main array and its hardware.

Automated summary

The High-Altitude Water Cherenkov (HAWC) observatory is a second-generation, wide field-of-view, TeV gamma-ray observatory built on the experience of the Milagro experiment. Located on the Sierra Negra volcano in Mexico, HAWC consists of 300 water Cherenkov detectors to analyze extensive air showers and study cosmic rays. The observatory is optimized to observe transient and steady emission from gamma-ray sources.