CTA: the future of ground-based γ-ray astrophysics

Very high energy (VHE; ) γ-rays provide a unique probe into the non-thermal processes in the universe. The ground-based Imaging Air Cherenkov telescopes (IACTs) for detecting VHE γ-rays have been perfected, so a relatively fast and inexpensive assembly of IACTs is now possible. Next generation instruments will have a sensitivity [∼]10 times better than current facilities, and will extend the accessible γ-ray bandwidth at both energy ends (down to 30 GeV and up to 300 TeV) with improved angular and energy resolutions. Some key physics drivers, that are discussed here, suit specific features of the upcoming IACT facility, the Cherenkov Telescope Array (CTA). The resulting technical solutions chosen for CTA, and the current status of the project, are also outlined.