HAWC, an acronym for High Altitude Water Cherenkov is a gamma-ray  observatory to be located at very high altitude (4100m) in the volcán Sierra Negra, México, near the Large Millimeter Telescope (LMT). HAWC is a project uniting  about twenty institutions in Mexico and the United States. The project is  headed in Mexico by INAOE and the United States by The University of Maryland.

The HAWC observatory will consist of 900 water tanks of up to 5 meters  in diameter each, covering an area of over 20,000 square meters. Each  tank will have at least one photomultiplier tube, which serves as a pixel in the  array of 900 detectors. In this way HAWC will detect cascades of  articles that  occur when a high-energy particle, i.e. a cosmic ray or gamma ray penetrates  Earth's atmosphere.

These cascades of particles cover an area of more than a hundred  meters in diameter and, studying the arrival and distribution of particles in  the soil, we can infer the direction from of arrival of the primary  high-energy particle and discriminate if it is a beacon gamma (signal) or a cosmic ray  (noise).

Cherenkov observatories water works best in places high and near the  equator. The first observatory Cherenkov water was the observatory  Milagro (, located in New Mexico. Considering the possibility of building an observatory fifteen times more  powerful, HAWC was specified to remain above the 4000 meters and sites in Bolivia, China and Mexico were initially considered. The excellent geographical location,  infrastructure of the LTM site in Sierra Negra and the existence of a large group of  Mexican institutions interested and with experience in other large projects  were crucial to ensure that the site of the observatory was in our country.

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Alberto Carramiñana-Alonso, Ph.D.,

Ibrahim Torres, Ph.D.,


Last update
24-09-2021 / 01:09 by Liliana Perea Centeno


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