IIHE Topical Seminar: Tracking Triggers in High Energy Physics Experiments

by Dr Jinyuan WU (Fermi National Accelerator Laboratory)

Thursday 10 Nov 2016, 15:30 → 16:30 Europe/Brussels

Jean Sacton Seminar room (1G003) (IIHE, VUB)

PLEASE TAKE NOTE OF THE UNUSUAL DAY AND TIME!

abstract: Charged track parameters such as momentum and angles have been important event selection primitives since the early age of experimental high energy physics. Nearly all high energy physics experiments have a trigger system based on coincidence of detector elements and the conditions of the coincidence usually cause certain constrains on the track parameters implicitly. In this sense, tracking triggers have existed for decades. Instead of “throwing out unwanted events”, the top requirement of a trigger system is to avoid creating fake “new physics” by reducing bias. Driven by physics requirements, detectors in accelerators such as LHC see very high hit rate with possible pile up of 200 interactions in each beam bunch crossing. The challenges of contemporary tracking trigger systems include encoding and transmitting detector hit information into trigger processors, matching hits into potential tracks and using the coordinates of the hits in track fitting process to calculate the track parameters as the trigger primitives. In contrary to the common intuition, the biggest challenge is not implementing sophisticated algorithms, but rather developing suitable and economical digital electronics building blocks. In this presentation, these challenges will be explained through several examples of both legacy experiments and on going new R&D projects. Various schemes of solving these challenges will be described and their advantages and disadvantages will discussed.