DØ Trigger Simulator Manual
Introduction to TrigSim

TrigSim is a program for running trigger simulation on either data or MC events. It has three basic goals:

• Evaluate trigger efficiencies and rejection on MC and data samples for triggers before they are run online.
• Test and debug online trigger software before it goes online.
• Verify performance of trigger algorithms and calculate efficiences after analysis.

The DØ trigger system consists of hardware at level 1 (L1), hardware and software at level 2 (L2), and software at level 3 (L3). TrigSim simulates the L1 trigger hardware and serves as a wrapper for the L2 and L3 code. It is configured using the trigger lists from the trigger database. Eventually it is hoped to have seemless operation over both data and Monte Carlo (MC). At the moment, some work on the part of the user is required. The output of TrigSim contains trigger objects as well as bit-masks. All of its output formats are identical to what is online.

TrigSim requires that its input file(s) contains a Raw Data Chunk (RDC). Files that come off the reco farms or files that your reco yourself generally DO NOT have an RDC (unless you modify reco RCPs yourself). TrigSim outputs information in several ways. It always produces a data file in the same format as the input file, but with one or more of the following additional chunks:

• L1L2Chunk
• L3Chunk (online and/or offline versions)
• L3DebugChunk (online and/or offline versions)