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<p>Folks,</p>
<p>Please find the minutes <a moz-do-not-send="true" href="https://halldweb.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_September_2,_2021#Minutes">here</a>
and below.</p>
<p> -- Mark</p>
<p> ___________________________________</p>
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<h2 id="firstHeading" class="firstHeading" lang="en"><span dir="auto">GlueX Start Counter Meeting</span><span class="mw-headline" id="Minutes"> Minutes</span><span dir="auto">, September 2, 2021, </span></h2>
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<p>Present: Eugene Chudakov, Mark Ito (chair), Simon
Taylor, Beni Zihlmann
</p>
<p>There is <a rel="nofollow" class="external text" href="https://bluejeans.com/s/uL11l3Qn6fR/">a
recording of this meeting</a> on the BlueJeans site.
Use your JLab credentials to gain access.
</p>
<h3><span class="mw-headline" id="Review_of_minutes_from_the_last_meeting">Review of
minutes from the last meeting</span></h3>
<p>We took a quick glance at the <a href="https://halldweb.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_July_22,_2021#Minutes" title="GlueX Start Counter Meeting, July 22, 2021">minutes
from July 22</a>. There was not a lot to discuss.
</p>
<h3><span class="mw-headline" id="Run_preparations">Run
preparations</span></h3>
<p>Two items of concern about the start counter as we go
into the run.
</p>
<ul>
<li> <b>Broad pedestals</b>. See <a rel="nofollow" class="external text" href="https://logbooks.jlab.org/entry/3897716">Beni's
logbook entry</a> for the details. This effect is
seen in all channels. Also the change occurred after
the last run, i.e., during a period when there was no
beam in the Hall. Sergey did a re-set of the pedestal
levels in the F250s and took data. Beni will look at
these new data next.</li>
<li> <b>Elevated temperature</b>. One of the ten
temperature channels (one channel per read-out board)
is anomalously high (several degrees C). See [<a rel="nofollow" class="external free" href="https://logbooks.jlab.org/entry/3897599">https://logbooks.jlab.org/entry/3897599</a>
Nick Sandoval's logbook entry for the details. Nick
found some pins in the cable that had been pushed out
of position, but fixing those reduced noise on the
signal but did not change the temperature level. Beni
will look at pedestals in the three channels on this
board and compare to the others.</li>
</ul>
<h3><span class="mw-headline" id="Bias_Voltage_Scan">Bias
Voltage Scan</span></h3>
<p>Beni pointed out that we have never looked at start
counter performance using bias voltages other than the
nominal ones. Mark will ask the BCAL folks about what
they have done on this, what they looked at in the data,
and what they learned from the exercise.
</p>
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