The Medium-Sized Telescope (MST) is being built by an international collaboration of institutes and universities from Austria, Brazil, France, Germany, Italy, Poland, Spain and Switzerland. This will be the CTAO’s “workhorse,” optimized to detect gamma rays in its core energy range, from about 150 GeV to 5 TeV. The planned Alpha Configuration for the CTAO includes 23 MSTs – 14 in the southern hemisphere and nine in the northern hemisphere. The MST will have 86 hexagonal-shaped mirrors that are aligned with an active mirror control assembly to create a uniform reflector of about 12 metres in diameter.
The MST is a modified Davies-Cotton telescope with a reflector size of 88 m² and a focal length of 16 m. It will have two different camera designs that use photomultiplier tubes (PMTs). The cameras have a field of view of about 8 degrees, enabling the MSTs to take rapid surveys of the gamma-ray sky.