Lambda spin fugacity measurement systematics
UPSAL LambdaPolarization BulkCorr September 9 2015.pdf is my 9/9/15 bulkcorr presentation
FitRobustness discusses the robustness of the fugacity fit depicted in my 9/9/15 bulkcorr presentatio (https://drupal.star.bnl.gov/STAR/blog/iupsal/lambda-polarization-bulkcorr-9915). In the file max likelihood fitting is compared to chi squared method as the minimum number of entries to be considered in a bin is increased. As this minimum is increased the chi squared fit (which initially looks bad - and should not necessarily look good) approaches the max likelihood fit, which stays constant.
In Fit Diff_E_Sy I compare the fit for different ranges in lambda energy, Sy, and Lambda Phi - Psi1 to check the thermalization hypothesis.
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UPDATE 10/14/15
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I no longer use a "random" event plane determination. In the BBC tiles 7 and 9 (as well as 11 and 13) share an adc value. The method (for BBC users) has typically been to assign all of the adc for that channel to 7 XOR 9 (see http://www.star.bnl.gov/public/bbc/ + Front View Drawing hyperlink for BBC geometry). I prefer to use a greyed out scheme whereby I assign half to 7 and half to 9 so that my results have no randomness. In previously posted slides here (before 10/14/15) I would use the random scheme. I have yet to discuss this idea with other BBC users.
A supplimentary BulkCorr talk is here:
https://drupal.star.bnl.gov/STAR/blog/iupsal/lambda-polarization-bulkcorr-oct-14-2015
I have also added centrality dependence. Average Sy systematics are on their way. I have not updated the fit robustness test. That still uses the "random BBC" which means that results may vary from nominal values. I have not yet characterized how much.
In Fit Diff_E_Sy I compare the fit for different ranges in lambda energy, Sy, and Lambda Phi - Psi1 to check the thermalization hypothesis. -- this has been redone for not random bbc
In RapidityDependence_NotRandomBBC I look at rapidity ranges (|y| < some number, y > 0, y < 0)
In CentralityDependence_NotRandomBBC I look at a few centrality range. -- Since none of these have a resolution correction yet a real signal could get some of this ordering (peripheral collisions have a larger signal) trivially from the poorer resolution correction at central collisions and the lack of lambda statistics at peripheral collisions (which probably kills the effect of low resolution at peripheral collisions).
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