Cherenkov Telescope Array

The Cherenkov Telescope Array or CTA is a multinational, worldwide project to build a new generation of ground-based gamma-ray instrument in the energy range extending from some tens of GeV to about 300 TeV. It is proposed as an open observatory and will consist of two arrays of imaging atmospheric Cherenkov telescopes (IACTs), a first array at the Northern Hemisphere with emphasis on the study of extragalactic objects at the lowest possible energies, and a second array at the Southern Hemisphere, which is to cover the full energy range and concentrate on galactic sources. The physics program of CTA goes beyond high energy astrophysics into cosmology and fundamental physics.

Building on the technology of current generation ground-based gamma-ray detectors (MAGIC, HESS, and VERITAS), CTA will be ten times more sensitive and have unprecedented accuracy in its detection of high-energy gamma rays. Current gamma-ray telescope arrays host up to five individual telescopes, but CTA is designed to detect gamma rays over a larger area and a wider range of views with more than 100 telescopes located in the northern and southern hemispheres. At least three classes of telescopes are required to cover the full CTA energy range (20 GeV to 300 TeV): Large-Sized Telescope (LST), Medium-Sized Telescope (MST) and Small-Sized Telescope (SST).

The project to build CTA is well-advanced: prototypes exist for all the proposed telescope designs and significant site characterization and preparations are underway. An inter-governmental agreement for construction and subsequent operation of the observatory, a European Research Infrastructure Consortium (ERIC), is in preparation and the financial threshold is expected to be reached in 2019.

The project was promoted to a Landmark on the road-map of the European Strategy Forum on Research Infrastructures (ESFRI), and is on the roadmaps for the European Astroparticle Physics network ASPERA and the European Astrophysics network ASTRONET. The cost for base-line design of the project is estimated at €300 million (US$350 million). The network is scheduled to start collecting data in 2022.