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HcalAlCaRecoProducers : Producer for HO calibration

• Outer hadron calorimeter is expected to improve jet energy resolution

• Due to different sampling/passive material in front of active material, HB and HO require different weight factor

• HO tiles should be calibrated with respect to each other before being weighted by a common weight factor to be used for better energy measurement

• There is no source calibration due to space constraints.

• Possibilities of calibrating HO tiles with

– Physics events only from W→μν (σ.Br=65.6 nb) and Z→μμ (σ.Br = 3.8 nb)

– Extrapolation to all possible physics events (mainly J/ψ (Υ(1S))

– Cosmic muon

A brief history :

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Comparison of HO signal and pedestal width in TB2006 & MTCC-I (no filed)

• Signal distribution is fitted with a (Gaussian (for ped)+Gaussian convoluted Landau (signal) in TB2006, for MTCC signal is fitted with only Gaussian convoluted Landau function

TB2006 MTCC

fC

fC

fC

fC

Pedestal Pedestal

Signal Signal

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Comparison of means with and without B-field (MTCC)

• There is no effect in ring-2, but ring-1 signal has gone down by a factor ~2, whereas cross talk is only about 10-25%

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Conclusion based on simple calculation

• 4% accuracy in HO calibration constant is achievable in 100 pb─1 data

• Muon from Υ(1S) and J/ψ can reduce uncertainty, but these processes have large uncertainty in production cross-sections

• One day cosmic muon run gives much better accuracy in Ring-1 and Ring-2, whereas for Ring-0, η-4, one need at least 4 days

• In the year 2008, a cosmic muon calibration is absolutely necessary, data from pp collisions will take longer time to achieve a reasonable accuracy, where as latter on (2009 onwards), data from pp collisions will be sufficient to calibrate HO.

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Inputs for the calibration constant • Trigger information (2)

• Muon momentum and position in DT (3+3)

• Other parameters of muon e.g., ndof, chisq, rechit (3)

• Error on Θ and Φ → on position at tile (2)

• Extrapolated track position (X,Y) at HO and tile number (2+1)

• Angle between track and HO tile (1)

• Signal in 3×3 tiles to verify muon reconstruction (9)

• Signals in all pixel of HPD to check cross-talk (18)

• Pedestal information (1)

• Associated HB+EB energy withing 0.3,0.5 and 0.7 (3)

• HB signal ? HO/HB time profile ?

In total there are 48+x variables per muon track, what was used in my own analysis with MTCC

All are put as a new DataFormats DataFormats/HOCalibHit/interface/HOCalibVariables.h and store as root objects along with other AOD/RECO

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Status of producer• Need to upgrade code which is compatable/useful with new library

(Original code with CMSW_1_0_0)

– There were no proper HO geometry in CMSSW, put it by hand

– No Proper track extrapolation, used by HelixArbitraryPlaneCrossing

– These are fine, but may be in future, move to data base for geometry and proper extrapolation function

• But, main problem with reconstruction of CosmicMuon.

– DT calibration constant, constant for cosmicmuons are totally different than muons from pp collisions

– CosmicMuonProducer has many dependency in CMSSW_1_5_2, which was not in 1_0_0

Not possible for 1_6_0, but hopefully by a week first version of code will be ready for cosmicmuon and also include for muons in physics run

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Configuration files• Calibration/HcalAlCaRecoProducers/test/make_hocalib_cosmicmu_152.cfg

(for cosmic events)

• or make_hocalib_physicsmu_152.cfg (for collision events)

• Necessary modifications for CosmicsMuons (in Calibration/HcalAlCaRecoProducers/data/)

– HOCosmicCalib_ecalLocalRecoSequence.cff

– HOCosmicCalib_FakeConditions.cff

– HOCosmicCalib_RecoLocalTracker.cff

– HOCosmicCalib_RecoLocalCalo.cff

– HOCosmicCalib_RecoLocalMuon.cff

– HOCosmicCalib_Reconstruction.cff

– HOCosmicCalib_RecoMuon.cff

– HOPhysicsCalib_Reconstruction.cff

– HOCosmicCalib_cosmicMuons.cfi (in future, it may be standard one)

– HOCosmicCalib_dt1DRecHits_LinearDrift_CosmicData.cfi (Same)

– ALCARECOHcalCalHO.cff

– ALCARECOHcalCalHO_Output.cff

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Options in Configuration files

• replace hoCalibProducer.muons = cosmicMuons // # standAloneMuons Cosmics muon or standalone muon (muon from pp collision)

• replace hoCalibProducer.digiInput = true // DIGI INPUT

• replace hoCalibProducer.hbinfo = false // No HB information

• replace hoCalibProducer.firstTS = 5 // first time slice

• replace hoCalibProducer.lastTS = 8 // last time slice

• replace hoCalibProducer.m_scale = 4.0 //Magnetic field scale factor

iEvent.put(hostore, "HOCalibVariableCollection"); where hostore = new std::vector<HOCalibVariables>

Store Events with other AOD/RECO objects,

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Analyzer

• Calibration/HcalCalibAlgos/src/HOcalibAnalyzer.cc

• In ::Analyze(….){ ….

– Edm::Handle<HOCalibVariableCollection> HOCalib;

– iEvent.getByLabel(“hoCalibProducer”,”HOCalibVariableCollection”, HOCalib;

– for (HOCalibVariableCollection::const_iterator hoC=(*HOCalib).begin(); hoC!=(*HOCalib).end(); hoC++){ …float signal = (*hoC).hosig[i]; ….}

– }

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Analyzer

• untracked string RootFileName = "analx_physicsmu_152.root“ //Root file name

• untracked string txtFileName = "analx_physicsmu_152.txt“ // text file for fitted parameters

• untracked string psFileName = "analx_physicsmu_152.ps“ //Postscript file for fitted plots

• untracked bool hbinfo =false // Analysis HB data or NOT?

• untracked bool hbtime =false // Do you want to see HB time profile (only for digi input)

• untracked bool hotime =false // Look for HO time profile (only for digi input)

• untracked bool correl =true // Do you want to see cross talk in nearby pixel as well as geometrically nearby tower (Checking of traking algorithms)

• untracked bool checkmap =true //Cross check of HO electronic map, may not usefull for users)

• untracked bool combined =true // For low statistics, look signal in each RM/Sector

• untracked bool get_constants =true // Get all calibration constant in the ascii file

Configuration file : Calibration/HcalCalibAlgos/test/anal_hocalib_152.cfg

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What more

• Many many points, but without those, we can use the existing code

• Put HO geometry from database

• Proper extrapolation function

• Selection of isolated muon in the data of “pp” collision

– Present criteria : # of hits >20, energy in HCAL <5.0 GeV

– Need to optimise

• When full detector is active, may be MTCC algorithms will have to modify/corrected

• Waiting for data (No cosmic data which are compatable with CMSSW_1_5(…)_X) and also this code inside the CMSSW software.

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Present status (Olga’s talk in CMSWEEK)

Policy not to change data formats ??