Detailed Tracking Task List, October 2003

1. Establish corrections for energy loss and magnetic field in the tracking system
   1. MC vs. Data study to determine correct material description for the real detector
      1. Study rate of photon conversions in Data vs. phi, r, z
         • We already have a file with 1M conversions!
         • need to make plots, quantify
      2. Study V-finding efficiency in Data vs. phi, r, eta
         • Use Kshorts, study lifetime vs phi, r, eta
         • need to make plots, quantify (Notre Dame student)
      3. Study rate of photon conversions in MC vs. phi, r, z
         • run tuple-making code over a large sample of photon conversions
         • need to make plots, quantify
         • compare results with what is seen in data to locate extra material
         • modulo tracking efficiency differences, this should give relative rates of material between Data and MC
      4. Study V-finding efficiency in Jet MC vs. phi, r, z
         • run tuple-making code over a large sample of p14 QCD MC
         • same Kshort study as data, but with MC truth
         • compare measured lifetime between Data and MC
         • check that tracking efficiency effects are cause of lifetime shifts
      5. Study rate of photon conversions in Jet MC vs. phi, r, z
         • use Jet tuples
         • need to make plots, quantify
         • compare results with what is seen in data
         • correct for tracking, V-finding efficiency differences in MC and Data
         • gives absolute rates of material in Data and MC
      6. Put correct material in Tracking code geometry description
         • use Kshort mass vs. mometum as a diagnostic
         • see if the behavior vs. momentum or energy is the same in MC
         • check on J/Psi, other samples
      7. Write code for TMB Corrections
         • needs to work on TMB as well, so parametrized form needed
         • requires check of energy loss corrections vs phi, p, eta, z, etc.
   2. Establish Magnetic Field magnitude, and direction(?) in tracking volume
      1. Study Kshort mass, after energy loss corrections, vs. z, phi, eta
         • might have to differentiate solenoid polarities
         • overall field normaliztation needed in central region
         • look for smoothly varying mass shifts in extrema of magnetic field
      2. Modify Magnetic field model to try and simulate any variance in Ks mass
      • can we see radial field components?
      • see if shape of variations can be made consistent with Bfield model
      3. Implement modified model, if needed
         • analytic corrections to calculated one - probably simplest
2. Understand tracking efficiency difference between MC and Data
   1. Understand single hit efficiency in CFT
      • comparison of ADC spectra for hits on tracks
      • comparison of ADC spectra for hits on tracks with MC+zerobias events to simulate noise
      • Study of gains (stereo, axial)/light yield in MC and Data
      • Study of threshold effects/global threshold cut in MC and Data
      • Include effects of dead channels (Database work)
   2. Tune MC to match what Data efficiency
      • should just be matching light yields
      • components include attenuation in waveguides, stereo/axial gains
   3. Study CFT clustering
      • comparison of cluster widths, width distribution to MC (MC+zerobias)
      • look for effects unexplained by single fiber performance
      • Study of clustering in general (resolution, size, etc)
   4. Understand single hit efficiency in SMT
      • comparison of ADC spectra for hits on tracks - is charge deposition/sharing correct?
      • comparison of ADC spectra for hits on tracks with MC+zerobias events to simulate noise
      • Study of clustering in general (resolution, size, etc)
      • Effects of dead channels?
   5. Implement modifications to SMT MC if needed
   6. Alignment studies
      • check for residual biases/errors in alignment of tracking detectors
      • creation of smeared alignment MC geometry to simulate residual problems
      • study of effects introduced by misalignments
3. Study/Improve Tracking in jets
   1. Detailed study of MC tracking in jets
      • where are tracks lost?
      • are more fake tracks generated?
      • if so, how?
      • Will require some digging around in the tracking code
   2. Suggest improvements to the tracking algorithms
      • track finding parameters based on hit density?
      • ?
4. Make Code run faster
   • profiling to look at execution speed
   • memory profiling to look at memory consumption, problems with freeing memory
   • algorithmic changes?
   • (pretty technical, expert-oriented)(SSS, Herb)
5. Fast Track Re-Fit from DST (say, with new alignment constants)
   1. small amount of code to remake GTrack objects including new clusters
   2. appropriate set of RCP parameters to do this
   3. fairly technical
6. Study/Verify Track errors/pulls for Central and Extrapolated Tracks
   1. Study "perfect" tracks in MC with no multiple scattering, interactions, etc.
      • are the track errors and parameters correct?
      • if not, find the bug(s)!
      • Check track extrapolation as well
      • slowly add effects of material and check that things stay ok
      • Will require some digging around in the MC (experts available for consultation)
   2. Look at current tracking errors in Data
      • do they look at all like the MC errors?
      • How big are the non-gaussian tails?
      • to what (most likely) can we attribute them?
      • should we develop a "smearing" routine for tail modelling?
7. Understand variation of efficiency with particle type
   1. pions, electrons, and muons have different tracking efficiencies (?)
   2. check MC/Data comparison
   3. investigate if they are very different after all of the above tasks are finished
8. Tracking with H-Disks?
   1. There are tracks out there with H-Disk hits...
   2. check residuals, difference in track errors with and without H disks
   3. check vertexing performance with and without H disks
   4. should we care about them?
9. Tracking using the FPS MiP Layer?
   1. The FPS could provide an extra tracking point in a region where our coverage is limited
   2. extrapolation study to FPS hits (MC)
      • extrapolate tracks to the FPS
      • study residuals of track extrapolation to FPS hits
      • Study improvement (or not) of track parameters by adding FPS hits
   3. extrapolation study to FPS hits (Data)
      • extrapolate tracks to the FPS
      • study efficiency of FPS in data
      • study residuals of track extrapolation to FPS hits
      • Study improvement (or not) of track parameters by adding FPS hits