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<p>Folks,</p>
<p>Please find the minutes from our last meeting <a
moz-do-not-send="true"
href="https://halldweb.jlab.org/wiki/index.php/GlueX_TOF_Meeting,_November_18,_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 TOF Meeting, November 18, 2020, </span><span
class="mw-headline" id="Minutes">Minutes</span></h2>
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lang="en">
<p>Present: Mark Ito (chair), Sasha Ostrovidov, Susan
Schadmand, Simon Taylor, Beni Zihlmann
</p>
<p>There is a <a rel="nofollow" class="external text"
href="https://bluejeans.com/s/Ql4TetXuMdl">recording
of this meeting</a>. Log into the <a rel="nofollow"
class="external text"
href="https://jlab.bluejeans.com">BlueJeans site</a>
first to gain access (use your JLab credentials).
</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 went over the <a
href="https://halldweb.jlab.org/wiki/index.php/GlueX_TOF_Meeting,_November_4,_2020#Minutes"
title="GlueX TOF Meeting, November 4, 2020">minutes
from November 4</a> without significant comment.
</p>
<h3><span class="mw-headline" id="Gain_Study">Gain Study</span></h3>
<p>Beni described the <a rel="nofollow" class="external
text" href="https://logbooks.jlab.org/entry/3857729">study
he did to look at PMT gains</a> at different beam
current conditions during the CPP test period in the run
just past.
</p>
<p>The apparent gains seem to rise significantly, 10-15%,
at low beam current, which is not what one would naively
expect. He think that the effect is due to low-level
background in the Hall dominating the pulse-height
spectrum when the beam is on. The spectra are averaged
on a channel-by-channel basis and there is no
coincidence requirement on each PMT. Beni plans to look
at individual amplitude distributions to confirm this
picture.
</p>
<p>He does see that the response from PMT 69 looks
suspicious in this study as well as in previous studies.
</p>
<h3><span class="mw-headline" id="TOF_NIM_paper">TOF NIM
paper</span></h3>
<p>Sasha reported that Paul Eugenio has been working on
the paper.
</p>
<h3><span class="mw-headline" id="Action_Item_Recap">Action
Item Recap</span></h3>
<ol>
<li> Decide on when to ship PMTs to JLab from FSU (Mark,
Paul Eugenio)</li>
<li> Prepare a complete draft of the TOF NIM paper.
(all)</li>
<li> Make a plan for TOF repair during the SAD,
including Paul in the discussion. (all)</li>
</ol>
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