Trigger

Introduction

At the high-energy high-luminosity environment of CDF, we have millions of interactions per second. Given the limited speed of any recording system, we are required to select real-time events that are interesting enough to be saved on tape. The hardware/software system that is responsible for this is called the trigger. CDF has a 3-level trigger system. The first two are implemented with hardware and the third one with software.


The XTRP

The XTRP is the unit of the trigger system of CDF that is responsible for extrapolating COT (central outer tracker) tracks to the outer part of the detector. Such a unit is crucial for triggering on objects that have to be partly reconstructed online using hardware.



I am responsible for the XTRP maps from the XFT (extreme fast tracker) to the CMU and CMX muon chambers. My work is crucial for the muon-based triggers, like the SUSY low-pT dimuon triggers that were used in my Supersymmetry analysis. I used J/&psi and Z data to model the response of the effect of the detector material and magnetic field on the trajectories of muons. The combined XTRP work was published in Nuclear Instruments and Methods A (Nucl. Inst. Meth. A 570, 36 (2007)).