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<u><b>Hoyoung:</b></u> (From Sept 7) Has done the packing fractions.
Going through and investigating those that are low values (~40% or so).
Some of the PF's seem to be really different, for different settings,
claiming to be of the same load. Oscar is going to check with James and
Jon once Hoyoung gives the run numbers. <br>
Will transpose the results to table format with the errors.<br>
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Packing_Fractions_Tables">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Packing_Fractions_Tables</a><br>
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<u><b>Hovhannes:</b></u> Looking at slow raster distribution for
perpendicular runs 72487-72550. Focusing on region where there are
holes; taking a slice of +-2mm around the center. Sees higher counts on
one side of SRx (with +- 2mm for SRy) compared to the other. Plus the
distribution looks trapezoidal. For the This could be an acceptance
effect, dependent on the angle. The SRy distribution (with +- 2mm for
SRx) looks more symmetric with peaks and troughs on the top probably
from the SR. These are fairly fine (few cm's) and won't really affect
things too much for BigCal, with a resolution of ~0.5cm. <br>
Started looking at perpendicular asymmetry, correcting for beam and
target polarization and live-time. The asymmetries are small but
stable. With a typical dilution factor of ~15% these will be reasonable.<br>
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<u><b>Narbe:</b></u> Following up on pi0 mass study(Aug 18), looking at
its dependence on energy. Using the GEANT, throwing pi0s from target
and smearing on reconstructed energy 9%, as seen in data. Initial
resolution of GEANT is significantly finer than data because GEANT
doesn't take into account the fact that the lead blocks are
radiation-damaged. Looked at pi0 mass in bins of reconstructed energy
(250MeV wide). The centroid of the peak seems to shift more to higher
values at higher energies. This is also seen in the data.<br>
Will move back on to the dilution factor effort and start working on
systematics for the kinematic variables.<br>
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/SANE_GEANT#09.2F08.2F2010">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/SANE_GEANT#09.2F08.2F2010</a><br>
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<u><b>Jon:</b></u> Did some work on the energy reconstruction to
cross-check calibrations, using earlier elastics data. Planning on
moving onto something else.<br>
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<u><b>Anusha:</b></u> After doing the slow raster calibrations for
offsets, sees that the elastic delta peaks have shifted more than
before. Looked at both early elastics data without field (left side
panels on link) and compared with polarized elastic data (right side
panels on link). Both show the extra shifting. Looking further into
this with Mark.<br>
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Magnetic_Field_ON/OFF_correlations">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Magnetic_Field_ON/OFF_correlations</a><br>
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<u><b>James:</b></u> (Posted last week) Looking at parallel
asymmetries, noticed a few runs (72945-72947) with half-wave plated
status being opposite of what the asymmetry should be. Did some
investigating and found that MCC had some ROC's crash around that time
and were rebooted, possibly back into their default state(s). It is
also possible that these are not synced with the EPICs. Made a table
for the helicity scalers per run.<br>
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Raw_Asymmetries#Charge_Normalized_Asymmetry:_8.2F25.2F2010">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Raw_Asymmetries#Charge_Normalized_Asymmetry:_8.2F25.2F2010</a><br>
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Dead_Time#Table_of_Scalers_per_Run:_8.2F25.2F2010">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Dead_Time#Table_of_Scalers_per_Run:_8.2F25.2F2010</a><br>
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As always, please let me know if I missed something or if I made a
mistake.<br>
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Next meeting will be Sept 15.<br>
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