Mattione Update 06012011

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Revision as of 15:08, 2 June 2011 by Pmatt (Talk | contribs) (Other Particle Masses)

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Overview

  • Generated and analyzed 10000 X(2000) -> b1π-; events following the instructions here.
    • Run using the latest build from this morning (contains fixes by David Lawrence on how the track vertexes are used to reconstruct events).
  • Decay chain:
 gamma p -> p X(2000)0
               |
               |-> b1(1235)+ π-
                    |
                    |-> ω π+
                          |
                          |-> ρ0 π0
                               |   |-> γ γ
                               |
                               |-> π+ π-

X(2000)0 Mass

  • X(2000)0: The combination of tracks yielding a mass closest to the X(2000)0.
  • 10000 generated events: ~63% reconstruction efficiency, was ~52% on the original b1pi wiki page.
  • However, very significant high-mass tail.
Code as of 06/01/2011


π0 Mass

  • π0: The combination of tracks yielding a mass closest to the π0.
  • Significantly worse resolution than originally: may now be more realistic, because reconstructed vertex is now used instead of the center of the target.
Code as of 06/01/2011


Original version on b1pi wiki page


Other Particle Masses

ρ0 Mass

  • ρ0:
Mattione Update 06012011 InvMass Rho0.gif


ω Mass

  • ω:
Mattione Update 06012011 InvMass Omega.gif


b1 Mass

  • b1:
Mattione Update 06012011 InvMass B1.gif


Track Multiplicity

# Generated events = 10000

# Events with 2+ photons = 9669
# Events with 2+ π+'s = 7749
# Events with 2+ π-'s = 8248
# Events with 2+ protons = 1040 (should only be 1 !!)
# Events with enough tracks for the X (2+ photons, 2+ π+'s, 2+ π-'s) = 6259
  • # Photons per Event
Mattione Update 06012011 NumPhotons.gif


  • # π+'s per Event
Mattione Update 06012011 NumPiPluses.gif


  • # π-'s per Event
Mattione Update 06012011 NumPiMinuses.gif


  • # Protons per Event
Mattione Update 06012011 NumProtons.gif


γ Reconstruction

  • γ's were reconstructed with p & E = 0 until a fix by David Lawrence this morning.
  • For each of the reconstructed photons that were matched with generated photons, Δp (reconstructed - generated) vs reconstructed p:
Code as of 06/01/2011, Δp (reconstructed - generated) vs reconstructed p