Difference between revisions of "Mattione Update 11302011"
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=== Procedure === | === Procedure === | ||
* Look at reconstructed dE/dx in CDC & FDC (treated separately: different gas mixtures). | * Look at reconstructed dE/dx in CDC & FDC (treated separately: different gas mixtures). | ||
+ | ** CDC: 52.6% CO<sub>2</sub>, 47.4% Argon | ||
+ | ** FDC: 62.0% CO<sub>2</sub>, 38.0% Argon | ||
** Half of the track hits in each of the FDC/CDC (those with the largest dE/dx) are ignored: truncates Landau distribution to resemble Gaussian distribution. | ** Half of the track hits in each of the FDC/CDC (those with the largest dE/dx) are ignored: truncates Landau distribution to resemble Gaussian distribution. | ||
* Fit mean and σ of these distributions and use them in calculation of χ<sup>2</sup> | * Fit mean and σ of these distributions and use them in calculation of χ<sup>2</sup> |
Latest revision as of 14:43, 30 November 2011
Contents
DC dE/dx Study Overview
Introduction
- DC dE/dx information used for PID is bad, is disabled until fixed.
- DC dE/dx Confidence Level (for protons, similar for K+'s, π+'s, and π-).
Procedure
- Look at reconstructed dE/dx in CDC & FDC (treated separately: different gas mixtures).
- CDC: 52.6% CO2, 47.4% Argon
- FDC: 62.0% CO2, 38.0% Argon
- Half of the track hits in each of the FDC/CDC (those with the largest dE/dx) are ignored: truncates Landau distribution to resemble Gaussian distribution.
- Fit mean and σ of these distributions and use them in calculation of χ2
FDC
- FDC π+ dE/dx μ & σ
- σ is dependent on amount of information: # hits USED (= 1/2 of total # hits: reject largest dE/dx hits to remove Landau tail)
- FDC protons dE/dx μ & σ
- σ is dependent on amount of information: # hits USED (= 1/2 of total # hits: reject largest dE/dx hits to remove Landau tail)
CDC
- CDC π+ dE/dx μ & σ
- σ is dependent on amount of information: # hits USED (= 1/2 of total # hits: reject largest dE/dx hits to remove Landau tail)
- CDC protons dE/dx μ & σ
- σ is dependent on amount of information: # hits USED (= 1/2 of total # hits: reject largest dE/dx hits to remove Landau tail)
CDC Proton Confidence Levels
- Confidence Level of all protons with # CDC hits >= 6 (# used hits > 3)
- Confidence Level of protons with varying # of CDC hits used
- Confidence Level of protons in CDC with different βγ