<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8">
</head>
<body bgcolor="#FFFFFF" text="#000000">
<p>Folks,</p>
<p>Find the minutes below and at
<a class="moz-txt-link-freetext" href="https://halldweb.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_August_26,_2016#Minutes">https://halldweb.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_August_26,_2016#Minutes</a>
.</p>
<p> -- Mark</p>
<p>______________________</p>
<p>
</p>
<div id="globalWrapper">
<div id="column-content">
<div id="content" class="mw-body" role="main">
<h2 id="firstHeading" class="firstHeading" lang="en"><span
dir="auto">GlueX Start Counter Meeting, August 26, 2016, </span><span
class="mw-headline" id="Minutes">Minutes</span></h2>
<div id="bodyContent" class="mw-body-content">
<div id="mw-content-text" dir="ltr" class="mw-content-ltr"
lang="en">
<p>Present:
</p>
<ul>
<li> <b>FIU</b>: Mahmoud Kamel, Werner Boeglin</li>
<li> <b>JLab</b>: Mark Ito (chair), Paul Mattione,
Simon Taylor, Beni Zihlmann</li>
<li> <b>NU</b>: Sean Dobbs</li>
</ul>
<p>There is a <a rel="nofollow" class="external text"
href="https://bluejeans.com/s/s6OQm/">recording of
this meeting</a> on the BlueJeans site.
</p>
<h3><span class="mw-headline" id="Efficiency_Update">Efficiency
Update</span></h3>
<p><a rel="nofollow" class="external text"
href="https://halldweb.jlab.org/talks/2016/SC_meeting_AUG25_2016.pdf">Mahmoud
presented slides</a> with updated efficiency
calculations and time resolution measurements. He used
the output of the start counter efficiency plugin,
written by Paul, from the reconstruction launch.
</p>
<p>He showed efficiency results for each counter for all
tracks, protons, π<sup>+</sup>, π<sup>−</sup>, K<sup>+</sup>,
K<sup>−</sup> where he used the nominal particle ID
provided by the plugin.
</p>
<p>He also showed efficiency for various sections along
the length of the start counter, 25 in all. There are
some azimuth variations in the raw occupancy, but they
do not show up in the efficiency calculation except for
the extreme forward sections.
</p>
<p>Time resolution was steady for most of the period of
the Spring 2016 run, with an average value of 281 ps.
There appears to be some slight reduction, about 25 ps,
of the resolution for 1350 A of solenoid current and 2
ns RF bucket separation. The origin of the effect is not
understood.
</p>
<h3><span class="mw-headline" id="Run_Readiness">Run
Readiness</span></h3>
<ul>
<li> Beni remarked that final readiness checks of the
detector cannot be performed until the FADC firmware
has been upgraded.</li>
<li> Mark will contact Eric Pooser and see if he can
help us with physical check-out in the Hall.</li>
<li> The hot-checkout procedure is straight-forward,
once everything is installed and powered up.</li>
<li> Beni mentioned that we will probably want to reduce
the time window for ADC read-out to keep the VME
backplane as quiet as possible.</li>
</ul>
<h3><span class="mw-headline" id="Calibration">Calibration</span></h3>
<p>Sean encouraged the group to write up the procedure for
start counter calibration in a GlueX Note. Werner
agreed, noting that the document should include
step-by-step instructions for performing the calibration
and we should develop the procedure so that those steps
are fairly well automated.</p>
</div>
</div>
</div>
</div>
</div>
</body>
</html>