In 2011, the First G-APD Cherenkov Telescope (FACT)
was assembled on the Canary Island of La Palma. Mounted in the focus of
one of the former HEGRA telescopes, the core of the FACT project is a
camera using pixels made of Geiger-mode avalanche photodiods (G-APDs).
Compared to the
currently used photomultiplier tubes (PMTs), G-APDs need a much lower
operation voltage, are more robust and have a higher photon detection
efficiency. Consequently, these devices are promising for an Imaging
Atmospheric Cherenkov Telescope (IACT) to improve the sensitivity of
the instrument compared to the currently used PMTs. As G-APDs can be
operated during strong moon light, they are ideal for a monitoring telescope
like FACT providing a larger duty cycle. The FACT project could show that G-APDs
in Cherenkov telescops work
(Anderhub et al. 2013).
Also the aim for robotic operation of the telescope will provide
valuable experiences for the CTA project.
- 1440 pixels
- 4.5 degree FOV
- Photo sensors: G-APDs
- Solid light guides