ATLAS FCal Test Beam 2003 Athena Analysis

This is a TWiki web page for the FCal community to cleary summarize and work on the Athena TB analysis. The figure to the right is an example of a 200 GeV electron event in the 4L position using the TopoCluster algorithm.

Contact Persons Louise Heelan

Run List: 4L

The following run lists are based on Peter Krieger's "Good Run List" and include runs that have been cut as the analysis progressed.

Electrons at 4L

The following table is a list of all the runs for electrons in the 4L position.

Energy [GeV] Run Numbers Comments
5 run3848-3864  
10 run3608-3640  
20 run3568-3572  
40 run3574-3591  
60 run3242-3258  
80 run2543-2552 "Noisy"
100 run2595-2612 "Noisy"
150 run2385 "Noisy"
200 run2324-2340  

The following table lists runs that were previously deemed as good, but have since been cut from the analysis.

Energy [GeV] Run Numbers Comments
10 run3516-3518 ?
  run3519-3547 ?
60 run3224-3233 ?
  run3446-3463 ?
80 run2553 very noisy run
  run3464-3480 ?
100 run3429-3445 ?
150 run2386 very noisy run (~900 GeV)
200 run1777-1779 ?
  run1781-1793 ?

Pions at 4L

The following table is a list of all the runs for pions in the 4L position.

Energy [GeV] Run Numbers Comments
10 run4006-4012  
20   no 20 GeV energy pions (really electrons)
40 run3870-3919  
60 run3259-3279  
80 run2856-2889  
100 run2613-2618  
120 run3094-3110  
150 run2344-2358  
200 run1749-1765  

The following table lists runs that were previously deemed as good, but have since been cut from the analysis.

Energy [GeV] Run Numbers Comments
10 run4023-4024 problem with beam envelope cut
40 run3973 BPCs tripped - could not generate beam envelope/cleaning cuts
60 run3281 problem reduced evts in logTree (5449 instead of 11210)
100 run2619 one of BPCs tripped - could not generate beam envelope/cleaning cuts
  run2636-2647 one BPC tripped
  run2648 changing beam conditions
150 run2375 no beam instrument intrument info - could not generate beam envelope/cleaning cuts
200 run2290 no beam instrument intrument info - could not generate beam envelope/cleaning cuts

Athena Analysis

Readout Channel Reconstruction

The LArFCalTBChannelBuilder algorithm was developed to reconstruct the energy for each individual readout channel. The following list are the steps used to determine the reconstructed energy for each readout channel:

  • Pedestal Subtraction: Retrieves the pedestal value from the dB for each channel and substract for each time sample.
  • Gain Correction: Applies a gain correcton based on the calibration data (see ITEP paper).
  • Amplitude Reconstruction: Calculates the amplitude of the readout channel using the method chosen.

There are presently three methods reconstruct the amplitude:

  • Max technique: uses the value of the maximum sample as the amplitude
  • Parabola technique: applies a parabola fits the samples to determine the amplitude.
  • OFC technique: uses the phase information to retrieve a set of OFC's then applies the OFC's on the samples to determine the amplitude.

Of the three methods, the OFC technique gives superior results and will be used for all future results.

The properties of LArFCalTBChannelBuilder algorithm are:

  • TBLArRawChannelBuilder.DigitContKey = "FREE"
  • TBLArRawChannelBuilder.RecoMode = "OFC"
  • TBLArRawChannelBuilder.OFC_Key = "LArOFC"
  • TBLArRawChannelBuilder.ADCtoMeVFCAL = [1,1,1]
  • TBLArRawChannelBuilder.TBPhaseKey = "TBPhase"
  • TBLArRawChannelBuilder.PhaseQuality = 0
  • TBLArRawChannelBuilder.UsePedestalDB = TRUE
  • TBLArRawChannelBuilder.PedestalKey = "LArPedestal"
  • TBLArRawChannelBuilder.PedestalOffset = 1
  • TBLArRawChannelBuilder.GainFactor = 9.2
  • TBLArRawChannelBuilder.FixGainFactor = FALSE
  • TBLArRawChannelBuilder.LArRawChannelKey = "LArRawChannels"


Will be added soon...

Using TopoCluster for the 2003 Test Beam

Due to electrode and nearest neighbor table mismapping the topological clustering is not currently used in the analysis (however stay tuned from the upgrade to Athena 13). For general information the text below has been kept.

The basic idea behind the CaloTopoClusterMaker algorithm is to group cells based on their neighbor relations and on the significance of their energy with respect to their noise. The properties set for the topocluster are:

  • CaloTopoClusterMaker.ClustersOutputName ="CaloTopoCluster"
  • CaloTopoClusterMaker.ClusterMakerTools =["CaloTopoClusterMaker/TopoCluster"]
  • CaloTopoClusterMaker.TopoCluster.CellsNames =["AllCalo"]
  • CaloTopoClusterMaker.TopoCluster.CalorimeterNames =["LARFCAL"]
  • CaloTopoClusterMaker.TopoCluster.UseCaloNoiseTool =TRUE
  • CaloTopoClusterMaker.TopoCluster.UsePileUpNoise =FALSE
  • CaloTopoClusterMaker.TopoCluster.NeighborOption ="all3D"
  • CaloTopoClusterMaker.TopoCluster.CellThresholdOnAbsEinSigma =0.0
  • CaloTopoClusterMaker.TopoCluster.NeighborThresholdOnAbsEinSigma =2.0
  • CaloTopoClusterMaker.TopoCluster.SeedThresholdOnEorAbsEinSigma =4.0
  • CaloTopoClusterMaker.TopoCluster.CellThresholdOnAbsEt =-1
  • CaloTopoClusterMaker.TopoCluster.NeighborThresholdOnAbsEt =-1
  • CaloTopoClusterMaker.TopoCluster.SeedThresholdOnEtorAbsEt =-1
  • CaloTopoClusterMaker.TopoCluster.ClusterEtorAbsEtCut =-1
  • CaloTopoClusterMaker.TopoCluster.SeedSamplingNames =["FCAL0","FCAL1","FCAL2"]
  • CaloTopoClusterMaker.TopoCluster.SeedCutsInAbsE =TRUE

For more up-to-date information about the topocluster go to the TopoCluster TWiki.

Using the SimpleNoiseToolFromTextFile tool

To improve the accuracy of the clustered cells using the CaloTopoClusterMaker algorithm we use a noise tool which was developed to read a ascii file. This ascii file contained the channel ID and the reconstructed noise for each readout cell. To use this noise tool, you must invoke the tool as follows:

  • CaloTopoClusterMaker.TopoCluster.CaloNoiseTool="SimpleNoiseToolFromTextFile/simplenoisetool"

Futhermore, you must set the properties of the noise tool:

  • CellNoiseFileName = "/files4/mschram/AtlasWork/11.0.2/fcaltb03/Noise2324_to2340.txt"
  • CellNoiseUnits = MeV
  • CellNoiseDefault = 3.20*MeV
  • CellNoiseDefaultWarning = TRUE

Creating a noise file for the SimpleNoiseToolFromTextFile tool

The LArFCalTBNoiseFileMaker algorithm was developed to create a noise file needed by the SimpleNoiseToolFromTextFile tool. It retrieves a set of OFC's from the dB and calculates the amplitude (reconstructed noise) from the random runs. The properties of LArFCalTBNoiseFileMaker algorithm are:

  • LArFCalTBNoiseFileMaker.DigitContKey = "FREE"
  • LArFCalTBNoiseFileMaker.OutputNoiseFile = "Noise2324_to2340.txt"
  • LArFCalTBNoiseFileMaker.ADCtoMeVFCAL = [1,1,1]
  • LArFCalTBNoiseFileMaker.OutputLevel = DEBUG

A sample job option script will be put in cvs as asap.

The plots below are of 200 GeV electron in the 4L position using CaloTopoClusterMaker with fixed noise (left) and using the noise tool (right). We can clearly is a second cluster in the left plot which should not be there.

Root Analysis

All of this code is in cvs, and should be run in the order listed below.

Merger Code

Does the merging of the physics analysis root files and random root files, cylinderical clustering, and application of the radial weights (optional). Also clusters the noise.

Beam Cleaning

Removes contaminating particles in the beam, upstream decays, multiple hits, etc.

RecoTiming for Halfling Removal

Events that have been poorly timed, and have not been cut out with the basic timing quality cuts (they results in a reconstructed energy of half the expected). Suspect wrong set of OFCs used.

Final Analysis Code

Production of linearity and resolution figures for electrons and pions with the final cuts. Also can regenerate the flat weights (constrained or unconstrained).

Analysis Goals

Data Analyses

  • Inner edge study with position 1,2,3 scans: examine the energy losses due to the beam pipe, and characteristics of the energy splashes across the beam pipe. Develop a correction factor (like a dead material correction) that depends on the cluster center. Work needs to be done to understand how clusters of one interaction are split across the beam pipe, and examine how the energy in those clusters are related (use cluster with maximum energy, but cluster all energy in event - but think about how this works with real jets, and multiple jets - how is this dealt with using the default athena clustering algorithms).

  • Position 4H: Examine the electron and pion energy resolution and linearity with the presence of the added upstream material. How does this compare to the ideal 4L position? Are we still within the required performance for ATLAS? Can we apply some dead material correction?


Monte Carlo Studies

  • Validate the MC with the 4L position (most simple - minimal upstream material, fully contained)

  • Use the MC and the data to determine the best physics lists to use in ATLAS (other test beams have influence the use of the QGSP_BERT physics lists, although it requires 2x as much computing)

  • Do a range cut study in the FCal - the default may not be necessary with our granularity.

  • Inner edge studies: ensure the MC correctly simulates the splashing and energy loss as compared to the data. Can also use to confirm energy loss down the beam pipe. And will need for other beam energies (only 200 GeV pions and electrons with data).


How to Setup the Package in Release 15

  1. Setup a 15.X.Y athena area (15.2.0 and 15.3.0 tested so far, July 24 2009). Instructions for how to setup athena at Carleton are at:
  2. Check out the following packages:
    # cd $TestArea
    cmt co -r LArTools-00-07-06 LArCalorimeter/LArTools
    cmt co -r LArFCALTBCnv-00-04-03 LArCalorimeter/LArCnv/LArFCALTBCnv
    cmt co -r LArFCALTBAna-00-03-06 LArCalorimeter/LArTestBeam/LArFCALTBAna
  3. Run the setup script and follow the instructions:
    cd LArCalorimeter/LArTestBeam/LArFCALTBAna/
  4. Done! Can now test to run. The release 15 jobOpiton files are in the the "run" folder:
    cd run

    # first modify location of data input file in jobOption file below, then run!
    athena 2>&1 | tee noise_maker.log

    grep ERR noise_maker.log # hopefully no errors...
  5. If there are errors (Tom had errors), a clean re-compilation of the analysis package in a new shell (terminal window) should solve it:
    cd LArCalorimeter/LArTestBeam/LArFCALTBAna/cmt
    cmt bro gmake clean
    cmt bro gmake
    Repeat the step in the previous check, and it should all be fine (if the errors are about the event selector, do the same thing but for the LArFCALTBCnv package).

Analysis Documents

Monte Carlo



Major updates:
-- Main.mschram - 05 Feb 2006 -- Main.mschram - 02 Feb 2006

Topic attachments
I Attachment History Action Size Date Who Comment
PNGpng 9a22271bd8148ae2e48e6b55a10a158b.png   manage 0.7 K 2006-02-02 - 19:29 UnknownUser  
Texttxt Athena15_data_MC_instructions.txt r1 manage 7.7 K 2010-08-12 - 20:38 UnknownUser Instructions for running the data analysis and Monte Carlo simulation in release 15
PDFpdf BeamCleaningAndEnvelope.pdf r1 manage 236.9 K 2008-05-15 - 15:53 LouiseHeelan  
Postscriptps r1 manage 308.6 K 2008-05-15 - 14:24 LouiseHeelan  
Unknown file formatcxx CBNTAA_CaloCell.cxx r1 manage 12.3 K 2008-05-15 - 14:37 LouiseHeelan  
Header fileh CBNTAA_CaloCell.h r1 manage 2.2 K 2008-05-15 - 14:37 LouiseHeelan  
Unknown file formatcxx CBNTAA_CaloCluster.cxx r1 manage 29.4 K 2008-05-15 - 14:37 LouiseHeelan  
Header fileh CBNTAA_CaloCluster.h r1 manage 5.9 K 2008-05-15 - 14:38 LouiseHeelan  
Texttxt DigiAndRecoInstruction.txt r1 manage 9.8 K 2008-05-15 - 14:41 LouiseHeelan  
PDFpdf KriegerComo2007.pdf r1 manage 3740.4 K 2008-05-21 - 17:34 PeterKrieger FCal Talk presented at Como conference, Oct. 2007
PDFpdf KriegerComoProceedings.pdf r1 manage 284.1 K 2008-05-21 - 17:35 PeterKrieger Conference Proceedings for Como 2007 FCal Presentation
PDFpdf LHeelan_LArWeekSept2008.pdf r1 manage 3320.5 K 2008-09-29 - 10:36 LouiseHeelan  
Texttxt NoiseFile.txt r1 manage 60.5 K 2008-05-15 - 14:38 LouiseHeelan  
PDFpdf TB2003_TopoAnd4LPosition_Electrons.pdf r1 manage 377.4 K 2008-05-15 - 15:54 LouiseHeelan  
Postscriptps r1 manage 713.6 K 2008-05-15 - 14:24 LouiseHeelan  
PDFpdf TB2003_TopoAnd4LPosition_Pions_v3.pdf r1 manage 253.0 K 2009-07-23 - 19:16 LouiseHeelan  
PNGpng cc6a557d6be1570086ec2bbbc652b6dd.png   manage 0.5 K 2006-02-02 - 19:29 UnknownUser  
PNGpng cdb8190790ee69dac94d92ae219ba9ae.png   manage 0.4 K 2006-02-02 - 16:49 UnknownUser  
PowerPointppt instructions_TB2003.ppt r1 manage 67.5 K 2008-05-15 - 14:36 LouiseHeelan  
PDFpdf jinst8_02_p02002.pdf r1 manage 1075.7 K 2008-05-21 - 17:37 PeterKrieger FCal 2003 Beam Test Publication1
Topic revision: r28 - 2010-08-12 - unknown
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