Calibration hits in Jets

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Calibration hits in Jets
A proposal for a package analyzing calibration
hits inside reconstructed jets
PierreAntoine Delsart Mohsen Kharzad Rachid
Mazini
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Package Overview

• Results from the code being written for forward
  jets analysis
• Quite generic thanks to back navigation
• ? can be useful to others
• Consists of one simple analysis algorithm

• It uses fully simulated events with calibration
  hits, produces an ntuple
• associates to each jet
• Sum of energy of the hits inside the jets
• An array corresponding to some calorimeter bins
• holding the jet energy deposition in each bin

This for each 'type' of energy (G4 Total, G4
visible, etc...)

• Calo is divided in
• geometric region (Barrel, Tile, HEC,...)
• Energy density bins (1 or 16) as in current
  hadronic calibration

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Package Details - Inputs
It requires ESD files containing
CaloCellContainers filled with Calibration hits.
Simulation with calibration hits
Reconstruction CalibHitToCaloCell algo
Digitization keep calib hits
- Add jobOption CalibHit_joboption.py - May
add 'topo jets'
Add this line in jobOption Stream1.ItemList"C
aloCalibrationHitContainer"
ESD file
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Package Details - algo
In each event, for each jet
NonEm Energy
Jets
Visible Energy
G4 CaloCellContainer
Total Energy
back navigation
G4 cells
reco cells
IdentifierHash

• EEcell
• Find and fill calo bin according to
• CaloSample and E density
• Other convenient calculation...

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Algorithm Output Analysis script
The algo produces an ntuple with jet related info
- Jet E, pT, eta, phi (for jets before and
after calibration) - same for (eta,phi)-matched
truth jet - G4 Total, visible, NonEm energy of
the jet - array of calo bins in the form
'ZoneEnergynjetnbin' for reco and all G4
energies - Radial energy profile of the jet
The granularity of calo bins is quite fine (505
bins) allows flexible analysis but information
extraction is not immediate A ROOT script is
provided allows to easily convert the initial
bin division into - Hadronic weight division -
Calo Sample division - custom division ...
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Analysis examples
(di-jet sample, E1Tev, etagt3)
Ratio E/Etruth in E density bins
Total jet energy/ True jet energy
distribution Reco/True G4 / True
G4 total G4 Visible G4 non EM Reco
Jets in HEC-FCAL crack
Hadronic weight binning
Ratio G4/Reco uncalibrated Calibration weights
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Work in progress open questions

• Dead Material hits information is being
  implemented in the algo
• - by building a (eta,phi) distribution of DM
  energy
• - associating each jet to a (eta,phi) DM
  subregion
• Currently having problems with cal hits in 10.0.4
  (wrong Ids).
• Being fixed...

If interest for this analysis algorithm, it is
ready to be released as a pakage - New package
(where ?) or add it to an existing package ? -
Easy to re-implement it as an Athena tool or algo
if prefered - Easy to extend it to any type of
calorimeter object (back navigation)
A test version is available here
/afs/cern.ch/user/d/delsart/publi/JetAnalysis.
tar.gz Please email me for details (delsart at
lps umontreal ca)