Reconstruction, July 7, 2009

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Revision as of 01:25, 7 July 2009 by Leverinb (Talk | contribs) (Reconstruction)

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Time: 11:00 EST/10:00 CST


Documents to Review

Tentative Agenda

  1. Reconstruction Physics Reactions
  2. Generating Background Events (Pythia: 124 μb @ 9GeV beam energy)
    • Shared data sets, filtering, et c.

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.

PI0MASS CHI2cut.pngProbMax PI0 CHI2cut.png ETAMASS CHI2cut.pngProbMax ETA CHI2cut.png


resonance mass

  • a combination of a0(980), a2(1320), a0(1450), a4(2000) resonances.

RESMASS CHI2cut.png


missing mass

RECMASS CHI2cut.png


momentum transfer

T CHI2cut.png

Background

Minutes