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<u><b>James:</b></u> Looking at asymmetries with kinematic binning
calculated by Narbe. Looked at parallel runs. The (average) Q^2 bins
of 3 and 4 [GeV^2] seem reasonable and the delta peak can be seen. The
upper-most bin of 5[GeV^2] seems to not have that much statistics.
Might re-bin, but want to see how the physics asymmetries look first.<br>
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Binned_Asymmetries#First_Look:_12.2F15.2F2010">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Binned_Asymmetries#First_Look:_12.2F15.2F2010</a><br>
Updated beam polarization tables. Found out, from Dave Gaskell and
Mark, that the dips seen in the quantum efficiencies were not real.
Replaced those with averaging before and after readings. <br>
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Beam_Polarization_Per_Run#Erroneous_QE_readings.2C_QE_correction:_12.2F15.2F2010">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Beam_Polarization_Per_Run#Erroneous_QE_readings.2C_QE_correction:_12.2F15.2F2010</a><br>
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<u><b>Luwani:</b></u> Looking at energy distributions for electrons and
neutral pions. The ratio of photons to electrons seems to be higher
than expected. Sorted neutral pion distributions by helicity. Also
looked at the 2 photon energies for the neutral pion final state. Will
check cuts. Hovhannes thinks there might be some multiple counting. <br>
<a class="moz-txt-link-freetext" href="https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Elections_and_pi0_plots">https://hallcweb.jlab.org/experiments/sane/wiki/index.php/Elections_and_pi0_plots</a><br>
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<u><b>Narbe:</b></u> Looking at cluster distributions with the
GEANT-MC, mainly positions, but also angles and energy (everything
dated Dec 10 and later). At first look(files with extension 'wrong'),
saw an uneven distribution between RCS and Protvino blacks, in that the
RCS blocks seems to have significantly less populating. There was also
a huge gap with no populating at all for almost 20-25% of the RCS
blocks. Along with Hovhannes, found that the block-size selection in
the code was being determined with the wrong index. This fixed the
empty gap issue, but not yet the large difference in populating between
the 2 block types. Seems like there is an offset on the RCS blocks.
Will check code and find bug(s).<br>
<a class="moz-txt-link-freetext" href="http://twist.phys.virginia.edu/~narbe/SANE/analysis/GEANT/acceptance/v5/5.25/?C=M;O=D">http://twist.phys.virginia.edu/~narbe/SANE/analysis/GEANT/acceptance/v5/5.25/?C=M;O=D</a><br>
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<u><b>Whit:</b></u> Developing an event display for looking at data.
This plots tracks and gives diagnostic plots relevant to the detectors.
Has something working and willing to let whoever is interested try it
out. In progress, but should be done fairly soon.<br>
Mentioned that some 'checksum' ought to be applied to the (raw)data
files being copied/cached over from the silo. This would be useful in
checking for files that corrupted in the caching over at times.<br>
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<u><b>Hovhannes/Mark/Oscar:</b></u> Looking into the issue of the
target's magnetic field. It seem that in the GEANT-MC the field is
possibly in the opposite direction. This means that the tracks are
being bent in the opposite direction of where they should be. Hovhannes
ran MC with field directions of +/-80 and 100 degrees. In this context,
looking downstream, positive implies left of beam and negative right
of beam. Oscar ran his stand-alone code and noticed that the beam has
the same deflection for +80 and -100, but opposite for -80. <br>
<a class="moz-txt-link-freetext" href="http://www.jlab.org/~rondon/sane/analysis/asym/a80_4.7_2/?C=M;O=D">http://www.jlab.org/~rondon/sane/analysis/asym/a80_4.7_2/?C=M;O=D</a><br>
Suggested cut on theta (for BETA) ~+40 ± ~1 deg and look at the
deflections GEANT gives for scattered electrons of 1.714 GeV for +80
and -80 and compare with his bdl numbers. The idea of whether the
target assembly might have been rotated to actually +100 degrees was
discussed but it seemed unlikely due to the likeliness of the HMS
acceptance being block by one of the coils. <br>
<a class="moz-txt-link-freetext" href="http://www.jlab.org/~rondon/sane/mtg13/sane_2007_0330.pdf">http://www.jlab.org/~rondon/sane/mtg13/sane_2007_0330.pdf</a> (see slide 6).<br>
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As always, please let me know if I missed anything, or if I made any
mistake(s).<br>
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Next meeting (<i>last one of 2010</i>) will be Wednesday December 21st
at 3:30pm. For the next meeting, the students giving talks for the
Winter Hall-C meeting on January 14/15 of 2011 will go over their
presentations.<br>
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