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<p>TOF'ers,</p>
<p>Find the minutes below and at
<a class="moz-txt-link-freetext" href="https://halldweb.jlab.org/wiki/index.php/GlueX_TOF_Meeting,_February_7,_2017#Minutes">https://halldweb.jlab.org/wiki/index.php/GlueX_TOF_Meeting,_February_7,_2017#Minutes</a>
.<br>
</p>
-- Mark<br>
______________________<br>
<div id="mw-content-text" dir="ltr" class="mw-content-ltr" lang="en">
<h2><span class="mw-headline" id="Minutes">Minutes</span></h2>
<p>Present:
</p>
<ul>
<li> <b>FSU</b>: Sasha Ostrovidov</li>
<li> <b>JLab</b>: Thomas Britton, Brad Cannon, Mark Ito
(chair), Simon Taylor, Beni Zihlmann</li>
</ul>
<p>There is a <a rel="nofollow" class="external text"
href="https://bluejeans.com/s/sA3G1/">recording of this
meeting</a> on the BlueJeans site. Use your JLab credentials.
</p>
<h3><span class="mw-headline" id="Lucite_Shield_Simulation">Lucite
Shield Simulation</span></h3>
<p>Thomas has added the Lucite shield to the geometry. He verified
its presence using using the HDDS-to-ROOT converter, but it
appears not to be showing up when viewed with hdgeant++. Simon
will consult on this. Other than this problem, the simulation
machinery is ready to go.
</p>
<h3><span class="mw-headline"
id="Review_of_minutes_from_the_previous_meeting">Review of
minutes from the previous meeting</span></h3>
<p>We went over the <a
href="https://halldweb.jlab.org/wiki/index.php/GlueX_TOF_Meeting,_January_24,_2017#Minutes"
title="GlueX TOF Meeting, January 24, 2017">minutes from
January 24</a>.
</p>
<ul>
<li> The broken FADC was replaced by Sascha Somov.</li>
<li> New reference plots for the TOF were added Friday.</li>
<li> Mark added a check-box for "Hists OK" on the run-by-run
info paper form.</li>
</ul>
<h3><span class="mw-headline" id="Run_Status">Run Status</span></h3>
<ul>
<li> <b>New HV Values</b>. <a rel="nofollow" class="external
text" href="https://logbooks.jlab.org/entry/3452533">Beni
loaded the new values</a>. No voltages are lower than 1200
V.</li>
<li> <b>Current draw and scaler rates as a function of beam
rate</b>. We need to study this for the new conditions. We
are currently running at "medium" current, 100 nA, with 30 kHz
trigger rate on a ? micron diamond.</li>
<li> Thresholds on the discriminators can be raised from here,
and must be for high rate tests, but are acceptable under
current conditions.</li>
</ul>
<h3><span class="mw-headline" id="Calibration">Calibration</span></h3>
<p>Beni thought the TOF timing calibrations were OK, but lately
discovered several channels where the constants do not make
sense. However, there are some good paddles and they show
resolution comparable to that obtained in Spring 16 with the
higher voltages we had at that time. The problem was due to fits
failing. A new set of constants has been produced and went into
the CCDB this morning.
</p>
<h3><span class="mw-headline" id="New_Base_Design">New Base Design</span></h3>
<p>Beni has tested a prototype from Vladimir Popov. The results
look good, though there is a signification DC offset at high
rate.
</p>
<h3><span class="mw-headline" id="Replacing_PMTs">Replacing PMTs</span></h3>
<p>Beni has had discussions with Tim Whitlatch and Tom Carstens on
changing some of the inner tubes after the run, perhaps as many
as 32. They are leaning toward a plan where the tubes are
replaced in situ (without dismounting the entire TOF planes).
</p>
</div>
<pre class="moz-signature" cols="72">--
<a class="moz-txt-link-abbreviated" href="mailto:marki@jlab.org">marki@jlab.org</a>, (757)269-5295
</pre>
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