[Sane-analysis] Minutes of 10/04/09 Meeting

[Narbe Kalantarians]

Hovhaness: Performed a systematic check of the perpendicular data 
regarding helicity information. In doing this he found a bad region 
where there was significantly less negative helicity counts relative to 
positive helicity counts. This appears to be from a  problem with the 
accelerator during the time of  that sub-set of data taking. He also 
redid the asymmetries with a raised cut on electron momentum (from 1 to 
1.1 GeV/c). This was done to eliminate background-accidentals. He will 
redo this with a few momentum bins. Plots can be seen on his wiki page 
under 'Systematic Check of DATA'.


Hoyoung: Redid HMS asymmetries with updated Analyzer. Seems to make some 
difference. Will try Hovhannes' latest corrections. Plots can be seen on 
his wiki page under 'Total HMS Asymmetries'.


Peter suggested plotting the HMS and BETA asymmetries together for 
comparison.


Narbe: Worked with Mark and found that xptar may loss of statistics for 
lower momentum perpendicular settings. This could be from more bending 
and hitting the collimator. Will look at the target window size to try 
to make some correction. Plots are on his wiki page under 'Packing 
Fractions' and todays date.
Steve Wood set up a database for accessing EPICS values for variables 
relevant to target analysis: 
https://hallcweb.jlab.org/targetlog/archives.html



Anusha: Comparing data and MC for tracking efficiency studies. This was 
with the 5.9 GeV perpendicular data. There seem to be some 
discrepancies, including something similar with xptar as to what Narbe 
has been seeing. Will look at SR distributions and try corrections from 
Peter to see if things improve. Will post soon.


James: Looking at TEs, writing PERL scripts to help sort out data better 
for calculations. Made a master summary file of TEs. Implemented the 
(Yale) gain factor corrections. These can all be seen on his wiki page.


Luwani: Looking at SR distributions for perpendicular data. At first 
glance it seems things look not too bad. Will redo plots in color to 
better see things. Will begin looking at beam position information for 
same sub-set.
http://www.jlab.org/~lzwano/aaa.png
http://www.jlab.org/~lzwano/aa.png