Difference between revisions of "Mattione Update 10312011"
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| − | == | + | == π(1600) -> b1pi Events, π<sup>+</sup> BCAL Δβ vs p == |
Δβ = β<sub>p</sub> - β<sub>t</sub> = p/sqrt(p*p + m*m) - path/(c*TOF) | Δβ = β<sub>p</sub> - β<sub>t</sub> = p/sqrt(p*p + m*m) - path/(c*TOF) | ||
| − | * | + | * π(1600) -> b1pi Events, π<sup>+</sup> BCAL Δβ vs p, 334 Segmentation: |
[[Image:Mattione_Update_10312011_BCALPiPlusDeltaBetaVsP_334Segmentation.gif|thumb|left|600px]] | [[Image:Mattione_Update_10312011_BCALPiPlusDeltaBetaVsP_334Segmentation.gif|thumb|left|600px]] | ||
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| − | * | + | * π(1600) -> b1pi Events, π<sup>+</sup> BCAL Δβ vs p, 1234 Segmentation: |
[[Image:Mattione_Update_10312011_BCALPiPlusDeltaBetaVsP_1234Segmentation.gif|thumb|left|600px]] | [[Image:Mattione_Update_10312011_BCALPiPlusDeltaBetaVsP_1234Segmentation.gif|thumb|left|600px]] | ||
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Revision as of 11:31, 31 October 2011
Contents
Procedure
- Reconstruct π(1600) -> b1π events with t-slope = 2.0 (was 5.0 for X(2000)) using both the 334 and 1234 segmentations
- Plot Δβ vs p for π+ candidates to see proton, π+ separation.
1234 Segmentation BCAL Time-Smear Details
- The 1234 segmentation is not available in the HDGEANT simulation, so its BCAL shower time was smeared manually during reconstruction
- The BCAL hit-time smear was disabled in mc_smear
- The shower time was smeared by: σsmear = sqrt(σ2t_334 - σ2t_334_NoSmear) * σt_1234 / σt_334
- These time uncertainties were studied as a function of dE and θ
- The σt_1234 / σt_334 ratio was obtained from fitting the results of David Lawrence's studies of photons
- The σ2t_334 and σ2t_334_NoSmear variances were determined separately for protons and pions
Improvements from last week's study
- Looking at π(1600) -> b1π events with t-slope = 2.0 instead of π(2000) -> b1π events with t-slope = 5.0: Higher proton momentum in BCAL for studying separation
- The σt_334_NoSmear resolution is no longer assumed to be zero: it is non-negligible in the region of the FDC support structure at for large energy deposits (determined separately for protons and pions)
- The σt_334 resolution is determined separately for protons and pions (was using the pion resolution for both previously)
David's BCAL Photon Time Resolution Studies
- γ BCAL σt vs. dE (GeV):
Time Resolution Segmentation Ratio
- γ BCAL σt_1234 / σt_334 vs. dE (GeV):
- Fits to γ BCAL σt_1234 / σt_334 vs. θ in dE bins:
- Don't trust fits at low-θ, so linearly-interpolate between 12 and 16 degrees.
BCAL π- 334 Segmentation σt Fits
- BCAL π- 334 Segmentation σt Fits vs. θ in dE bins:
π(1600) -> b1pi Events, π+ BCAL Δβ vs p
Δβ = βp - βt = p/sqrt(p*p + m*m) - path/(c*TOF)
- π(1600) -> b1pi Events, π+ BCAL Δβ vs p, 334 Segmentation:
- π(1600) -> b1pi Events, π+ BCAL Δβ vs p, 1234 Segmentation:
