A Topological Trigger System for Imaging Atmospheric-Cherenkov Telescopes

Details A Topological Trigger System for Imaging Atmospheric-Cherenkov Telescopes A Topological Trigger System for Imaging Atmospheric-Cherenkov Telescopes

2009-08-03

arxiv.org/abs/0908.0179v1

Astronomy and Astrophysics

Astrophysics

Instrumentation and Methods for Astrophysics

4 pages, 6 figures, to be published in Proceedings of the 31st International Cosmic Ray Conference (ICRC), Lodz, Poland, July

Scientific paper

A fast trigger system is being designed as a potential upgrade to VERITAS, or as the basis for a future array of imaging atmospheric-Cherenkov telescopes such as AGIS. The scientific goal is a reduction of the energy threshold by a factor of 2 over the current threshold of VERITAS of around 130 GeV. The trigger is being designed to suppress both accidentals from the night-sky background and cosmic rays. The trigger uses field-programmable gate arrays (FPGAs) so that it is adaptable to different observing modes and special physics triggers, e.g. pulsars. The trigger consists of three levels: The level 1 (L1.5) trigger operating on each telescope camera samples the discriminated pixels at a rate of 400 MHz and searches for nearest-neighbor coincidences. In L1.5, the received discriminated signals are delay-compensated with an accuracy of 0.078 ns, facilitating a short coincidence time-window between any nearest neighbor of 5 ns. The hit pixels are then sent to a second trigger level (L2) that parameterizes the image shape and transmits this information along with a GPS time stamp to the array-level trigger (L3) at a rate of 10 MHz via a fiber optic link. The FPGA-based event analysis on L3 searches for coincident time-stamps from multiple telescopes and carries out a comparison of the image parameters against a look-up table at a rate of 10 kHz. A test of the single-telescope trigger was carried out in spring 2009 on one VERITAS telescope.

Affiliated with

Also associated with

No associations

Rating

A Topological Trigger System for Imaging Atmospheric-Cherenkov Telescopes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with A Topological Trigger System for Imaging Atmospheric-Cherenkov Telescopes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Topological Trigger System for Imaging Atmospheric-Cherenkov Telescopes will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-453315