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<p>Please find the minutes below and in <a moz-do-not-send="true"
href="https://halldweb.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_June_15,_2017#Minutes">their
usual location</a>.</p>
<p>_______________</p>
<h2><span class="mw-headline" id="Minutes">Minutes</span></h2>
<p>Present:
</p>
<ul>
<li> <b>FIU</b>: Mahmoud Kamel</li>
<li> <b>JLab</b>: Thomas Britton, Mark Ito (chair), Eric Pooser,
Simon Taylor</li>
</ul>
<p>There is a <a rel="nofollow" class="external text"
href="https://bluejeans.com/s/niDbe/">recording of this meeting</a>
on the <a rel="nofollow" class="external text"
href="https://jlab.bluejeans.com/">BlueJeans site</a>.
</p>
<h3><span class="mw-headline" id="Calibration">Calibration</span></h3>
<ul>
<li> Mahmoud showed progress with determination of the counter
attenuation lengths from data. He is currently having
difficulties in having fits converge to the distributions of
pulse area in various bins of position. Please see the recording
for the plots. The data themselves looks good. There were
various suggestions on how to get reliable convergence (e. g.,
removing pedestal noise peak completely from the fit region).</li>
<li> Mahmoud also showed updated efficiency measurements. See <a
rel="nofollow" class="external text"
href="https://halldweb.jlab.org/talks/2017/Data_Production_Analysis.pdf">his
slides</a> for the details. His efficiency has dropped
compared to previous studies, but we think that that may be
because the time cut he uses to identify accidental background
includes a significant amount of signal, causing
over-subtraction.</li>
<li> In the same set of slides he showed the projected
intersection position of charged tracks with the start counter,
for all sectors, in the r-z projection. The looser matching cut
in the new software is manifest.</li>
</ul>
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