This page presents an attempt to use the trigger TEM diagnostic information to recognize calorimeter ghost signal.
Pass 8 Recon & Analysis Upgrades Weekly Meeting Agenda
Summary
Information available
- The TEM trigger diagnostic information provides trigger information on CalLo and CalHi per each layer end.
- From Sasha:
The code example for accessing CAL diagnostic info I can recommend you is the algorithm from calibGenCAL package used for trigger thresholds measurement:
/afs/slac/g/glast/users/chehtman/calibGenCAL_analysis/calibGenCAL/calibGenCAL-05-06-00/src/lib/Algs/LPATrigAlg.cxx
The method
LPATrigAlg::fillTrigBitArray()
just extracts CAL trigger bits from a digi file and puts them into some local structure. - As a reminder, CalLo is at 100 MeV and CalHi at 1 GeV.
Analysis
- Starting from Sasha's example, I wrote a piece of code that does the following:
- open digi, recon, merit and relation files
reads digi to create two arrays of layer end trigger bits [tower][layer][face] , one for CalLo and one for CalHi
- open recon and loop on clusters, then for each cluter
- open the corresponding crystal collection
- check if any crystal end has more than 100 MeV (or whatever other threshold)
- if any, then look if the corresponding layer end has a trigger bit set
- if not so, fill in a map of missing trigger bits and add 1 to a so called "cal ghost number"
- for each cluster, the higher the ghost number, the higher the probability that it's a ghost... but it looks like that aobve 2, they're all ghosts.
- Basic version of the code: tagghosts.C