HAWC is a facility designed to observe gamma rays and cosmic rays between 100 GeV and 100 TeV. TeV gamma rays are the highest energy photons ever observed — 1 TeV is 1 trillion electron volts (eV), about 1 trillion times more energetic than visible light! These photons are born in the most extreme environments in the known universe: supernova explosions, active galactic nuclei, and gamma-ray bursts.
Cosmic rays are charged particles which achieve energies far beyond what we can create in man-made particle accelerators. (The highest energy cosmic ray ever observed was 300 million TeV.) The origin of such particles has been a mystery for over 100 years. Gamma rays are though to be correlated with the acceleration sites of charged cosmic rays, so we observe them to help answer this and other cosmic questions.
HAWC is located on the flanks of the Sierra Negra volcano near Puebla, Mexico at an altitude of 4100 meters (13,500 feet). The detector has an instantaneous field of view covering 15% of the sky, and during each 24 hour period HAWC observes two-thirds of the sky. Using the HAWC Observatory, we are performing a high-sensitivity synoptic survey of the gamma rays from the Northern Hemisphere.