Difference between revisions of "Mattione Update 11072011"

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(Problems)
(π(1600) -> b1pi Events)
 
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* Plot &Delta;&beta; vs p for &pi;<sup>+</sup> candidates to see proton, &pi;<sup>+</sup> separation.
 
* Plot &Delta;&beta; vs p for &pi;<sup>+</sup> candidates to see proton, &pi;<sup>+</sup> separation.
  
== &pi;(1600) -> b1pi Events ==
+
== &pi;(1600) -> b1&pi; Events ==
  
 
=== p vs. &theta; ===
 
=== p vs. &theta; ===
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<br style="clear:both;"/>
 
<br style="clear:both;"/>
  
* &pi;(1600) -> b1pi Events, &pi;<sup>+</sup> Candidates, BCAL &Delta;&beta; vs p, 334 Segmentation
+
* &pi;(1600) -> b1&pi; Events, &pi;<sup>+</sup> Candidates, BCAL &Delta;&beta; vs p, 334 Segmentation
 
{| class="wikitable"
 
{| class="wikitable"
 
| [[Image:Mattione_Update_10312011_BCALPiPlusDeltaBetaVsP1200MeV_334Segmentation.gif|thumb|left|400px|p = 1.2 GeV/c, 334 Segmentation]]
 
| [[Image:Mattione_Update_10312011_BCALPiPlusDeltaBetaVsP1200MeV_334Segmentation.gif|thumb|left|400px|p = 1.2 GeV/c, 334 Segmentation]]

Latest revision as of 14:50, 7 November 2011

Procedure

  • Reconstruct π(1600) -> b1π events with t-slope = 2.0 using both the 334 and 1234 segmentations
  • Plot Δβ vs p for π+ candidates to see proton, π+ separation.

π(1600) -> b1π Events

p vs. θ

  • p vs. θ
    • NOTE: time improvement only at forward angles, so will be negligible for protons in this reaction.
π+'s
protons

π+ BCAL Δβ vs p

Δβ = βp - βt = p/sqrt(p*p + m*m) - path/(c*TOF)

334 Segmentation


  • π(1600) -> b1π Events, π+ Candidates, BCAL Δβ vs p, 334 Segmentation
p = 1.2 GeV/c, 334 Segmentation
p = 1.4 GeV/c, 334 Segmentation
p = 1.5 GeV/c, 334 Segmentation
p = 1.6 GeV/c, 334 Segmentation

Problems

  • π+ Reconstructed BCAL Time Resolution Sample dE bin:
    • Expect to see significant resolution improvement between 15 < θ < 35.
    • NOTE: For 1234 Scheme: the shower time was smeared by: σsmear = sqrt(σ2t_1234_Target - σ2t_334_NoSmear), where σt_1234_Target = σt_334*Improvement_Ratio, Improvement_Ratio = σt_1234 / σt_334
Mattione Update 11072011 BCALPiPlusSigmaTCompare Bin1.gif


  • π+ BCAL Shower Δt Sample θ bin, Time Smearing Disabled:
    • Δt = t_reconstructed - t_true
    • Instead of a spike at zero, the long tail is due to the hit clustering.
    • Will decrease 1234 time smearing to match expected resolution improvement to 334.
Mattione Update 11072011 BCALPiPlusSigmaTNoSmear SingleBin.gif


Reference

  • Fit the results of David's study: Fit γ BCAL σt_1234 / σt_334 vs. θ in dE bins: show significant (> 10%) timing improvement is between 15 < θ < 35.
    • Don't trust fits at low-θ, so linearly-interpolate between 12 and 16 degrees.
Mattione Update 10312011 BCALPhotonTimeResolutionRatio Fits1.gif