The Topo-trigger: a new concept of trigger for IACTs

by Rubén López-Coto (IFAE)

Wednesday 14 May 2014, 13:00 → 14:00 Europe/Madrid

Seminar (IFAE)

Imaging Atmospheric Cherenkov Telescopes (IACTs) such as the Major Atmospheric Gamma-ray Imaging Cherenkov (MAGIC) telescopes or the forthcoming Large Size Telescopes (LSTs) for the Cherenkov Telescope Array (CTA) are built to achieve the lowest possible energy threshold. The trigger system of these telescopes is one of the most important parts to achieve it. The main problem when decreasing the energy triggered by an IACT is the rapid increase of triggered events due to the accidental triggers caused by the ambient light, called Night Sky Background (NSB). The coincidence trigger between the telescopes strongly suppresses accidental trigger rate, but at even lower trigger threshold, there is no way to discriminate between the triggers produced by accidentals or real cosmic events. At IFAE we have developed the concept of a topological trigger, dubbed TOPO-trigger, a novel technique that allows a one order of magnitude decrease of the accidental events triggering MAGIC system in stereo. I will present the results of how this will improve the performance of the telescope.