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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,_October_29,_2020#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, October 29, 2020,
</span><span class="mw-headline" id="Minutes">Minutes</span></h2>
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lang="en">
<p>Present: Rupesh Dotel, Mark Ito (chair), Simon Taylor,
Beni Zihlmann
</p>
<p>The main item of discussion was Beni's report on what
he has gleaned thus far from the paper by Qiang, Zorn,
Barbosa, and Smith on <a rel="nofollow" class="external
text"
href="https://halldweb.jlab.org/talks/2020/SiPM_Radiation_Hardness_Final.pdf">Radiation
Hardness Tests of SiPMs for the JLab Hall D Barrel
Calorimeter</a>
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<ul>
<li> The authors conclude that SiPMs in the BCAL will
last for the lifetime of GlueX.</li>
<li> They do not address the situation for the start
counter, so the question is if we can assess the
neutron flux and/or radiation to the SiPM so much
nearer the beam line.</li>
<li> Beni has doubts about whether we can measure dark
current in situ in the Hall.</li>
<li> The asymptotic level of recovery from annealing is
better at higher temperature.</li>
<li> There is no history of annealing encoded in the
SiPMs; an annealing session at low temperature does
not adversely affect a later session at a higher
temperature.</li>
</ul>
<h3><span class="mw-headline" id="Action_Item_Review">Action
Item Review</span></h3>
<ol>
<li> Document calibration procedure (Rupesh)</li>
<li> Reproduce Beni's dark current results. (Tolga)</li>
<li> Continue to revisit Yi's study of SiPM annealing.
(Mark, Beni)</li>
<li> Look up type of SiPMs used in start counter. (Mark)</li>
</ol>
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