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<u><b>James:</b></u> Updated asymmetries using table of corrected
half-wave plate status for each run and also correcting for live-times.
Will take out runs with live-times of less than 30%. To account for
background, might consider looking at Cerenkov out of time.<br>
Put together a list of target polarization change (i.e. how much in
percentage the target polarization increased or decreased) for each
run. Might consider taking out runs with target pol. change of greater
than 5%.<br>
Oscar noticed that for the 4.7GeV perp data the early part was mostly
from Bottom cup and the latter part was mostly from Top cup. This might
be relevant to the puzzling change of packing fraction seen in the
period of changing from perp to parallel using the same load.<br>
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Raw_Asymmetries#Updates_to_Asyms_from_HWP.2C_LT:_12.2F8.2F2010">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Raw_Asymmetries#Updates_to_Asyms_from_HWP.2C_LT:_12.2F8.2F2010</a><br>
Tracking to target. Taking difference of target -y position, projected
from BigCal to (Front)Tracker, with and without Bdl as a function of
E'. The spread is larger at lower E', as expected. Can almost see a 2
different deflections as E' is decreasing, possibly indicating e+/e-
pairs.
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Particle_Tracking_to_Front_Tracker%2C_Target#Difference_in_Y_position_at_Target_using_Bdl:_12.2F8.2F2010">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Particle_Tracking_to_Front_Tracker%2C_Target#Difference_in_Y_position_at_Target_using_Bdl:_12.2F8.2F2010</a><br>
Mark suggested superimposing a calcualted curve for the electrons for
better visual. The smearing at E' < 0.5GeV is also from the neural
network not working too well at that range. Will cut out E'<0.5GeV.
Jon will compare with MC.<br>
<br>
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<u><b>Luwani:</b></u> Looking at energy distribution for neutral pions.
Distribution seems to be towards higher E' (>1GeV). This fro madding
the energy for the 2 final-state photons. <br>
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Background_from_Pi0_decay">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Background_from_Pi0_decay</a><br>
Will make a similar plot for electrons ans sort pi0 distributions by
helicity to get asymmetry.<br>
<br>
<br>
<u><b>Hovhannes:</b></u> Plotting azimuthal and polar (physics) angles
vs. each other to look at the efficiencies. Using cuts of <br>
nclust=1 and E_clust>1GeV for 5.9GeV perp data. Reversing the
direction of the field seems to make the distribution seem more
reasonable. Mark said that the coincidence data didn't show signs of
the analysis-engine having it reversed. This brought the question of
whether the field direction is correct in the MC used for training the
neural network. James had seen some possible hint of this back in
11/17/10. Will check this.<br>
<br>
<br>
<u><b>Oscar:</b></u> Made similar plots with 5.9GeV perp data to
cross-check Hovhannes. Sees similar distributions. Notices that the
Cerenkov makes a significant difference in the distributions,
redistributing some of the events. Will try binning in E'. Jon is
looking through the Cerenkov part of the analysis-engine to see what is
being done. The BigCal x&y distributions should also be looked at.<br>
<a class="moz-txt-link-freetext" href="http://www.jlab.org/~rondon/sane/analysis/replay/phi-theta/">http://www.jlab.org/~rondon/sane/analysis/replay/phi-theta/</a><br>
<br>
As always, please let me know if I missed anything or if I made any
mistakes.<br>
<br>
Next meeting will be December 15th.<br>
<br>
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