Reconstruction, July 7, 2009
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Time: 11:00 EST/10:00 CST
- See GlueX Communications for detailed instructions
- ESNET Number 8542553
Contents
Documents to Review
- Reconstruction References
- Reconstruction document in progress
Tentative Agenda
- Reconstruction Physics Reactions
- Generating Background Events (Pythia: 124 μb @ 9GeV beam energy)
- Shared data sets, filtering, et c.
- Angular distributions in GlueXAmpTools? (seems to be flat regardless of spin, no structure in cosGJ - Blake)
Discussion
Reconstruction
- It is required that there are 4 photons showers and none are due to charged particles, this gives 6 possible combinations.
- Pi0 and Eta candidates are chosen as the eta-pi0 pair with the largest probability (from the fit)
- Before cuts ~51% of the generated events can be reconstructed. A cut on χ^2 < 3 leaves approximately 39% of generated events,
Pi0 and Eta masses the line in red is cutting on chi^2 < 3.
resonance mass
- a combination of a0(980), a2(1320), a0(1450), a4(2000) resonances.
missing mass
- the missing 4-momentum can be calculated from the eta, pi0, beam and target 4-momenta.
momentum transfer