<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
</head>
<body>
<p>Folks,</p>
<p>Please find the minutes <a moz-do-not-send="true"
href="https://halldweb.jlab.org/wiki/index.php/%CE%A0_polarizability_Meeting_Mar_23,_2022#Minutes">here</a>
and below.</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">Minutes, Π polarizability Meeting Mar 23, 2022</span></h2>
Present: Alex Austregesilo, Albert Fabrizi, Sergey Furletov,
David Hornidge, Mark Ito (chair), Igal Jaegle, Nikhil Kalra,
Ilya Larin, Rory Miskimen, Simon Taylor, Beni Zihlmann
</div>
</div>
</div>
<div id="globalWrapper">
<div id="column-content">
<div id="content" class="mw-body" role="main">
<div id="bodyContent" class="mw-body-content">
<div id="mw-content-text" dir="ltr" class="mw-content-ltr"
lang="en">
<p>There is a <a rel="nofollow" class="external text"
href="https://jlab-org.zoomgov.com/rec/share/Wm2xjPp033bWQXRTmj3OaICnctXANcD-f_KLfl_7ycZidpu2CzwK8SFr_N_Kg_yM.wp1IrII1OPQXB4sq">recording
of this meeting</a> (Passcode: n.1a#yZ9) on the
ZoomGov website.
</p>
<h3><span class="mw-headline" id="Cables">Cables</span></h3>
<p>Beni reported that the LV and HV cables for the
chambers were being installed yesterday. The signal
cables are still in productions. He reminded us that we
have 6 signal cables in hand that can be used to test
one chamber at a time.
</p>
<p>[Added in press, from Beni: the crimp tool loan
mentioned at the last meeting was approved yesterday and
has been shipped to the company. Also Chris Stanislav is
connecting the LV boxes to the wire chambers as of this
afternoon.]
</p>
<h3><span class="mw-headline" id="Run_Start_Date">Run
Start Date</span></h3>
<p>Beni reminded us that the run is scheduled to start
June 8. We should not now that a budget has passed, we
should not assume that there will be a CR-related delay
in the start of the run.
</p>
<h3><span class="mw-headline" id="TAC_Status">TAC Status</span></h3>
<p>Beni had a look at the lead glass TAC in the Hall. He
led us through <a rel="nofollow" class="external text"
href="https://logbooks.jlab.org/entry/3989007">his
logbook entry</a>. All indications are that the device
looks good. He mentioned that that TAC was last used
with GlueX in November/December 2019.
</p>
<p>Beni also mentioned Sascha Somov's plan to use a new,
3×3 lead tungstate array as a TAC for CPP and PrimEx. We
had some discussion of the relative merits of lead glass
TAC vs. lead tungstate TAC.
</p>
<ul>
<li> possible leakage of showers from the sides of PbWO<sub>4</sub>
vs. large size of Pb-glass</li>
<li> better intrinsic energy resolution of PbWO<sub>4</sub></li>
<li> possible need for calibration, block-to-block of a
PbWO<sub>4</sub> array
<ul>
<li> TAC stage only has horizontal motion. Snake
scan requires two-dimensional motion</li>
</ul>
</li>
<li> PbWO<sub>4</sub> is a new detector</li>
</ul>
<p>Rory suggested that Mark ask Sascha to come to
tomorrow's CPP Design meeting to present his plan.
</p>
<h3><span class="mw-headline"
id="Amount_of_Empty_Target_Data_to_Take">Amount of
Empty Target Data to Take</span></h3>
<p>TBD
</p>
<h3><span class="mw-headline" id="Diamond_Simulations">Diamond
Simulations</span></h3>
<p>No news.
</p>
<h3><span class="mw-headline" id="Software.2FCalibration">Software/Calibration</span></h3>
<ul>
<li> Simon has moved the kinematic fit of pairs from a
plugin to a factory in the FMWPC library. It has not
been tested on electron-positron pairs yet. Rory
remarked that its location in this library is
motivated by having results of the fits available for
online e/π separation monitoring. Without the
kinematic fit, this would be difficult due to the
relatively poor momentum resolution for forward-going
tracks.</li>
<li> Simon is working on putting the survey numbers in.
He has a version in a private HDDS directory.</li>
</ul>
<h3><span class="mw-headline" id="Scintillators">Scintillators</span></h3>
<p>The CTOF paddles are being installed in the Hall this
week. Bobby Bunton 3D-printed mounting brackets, at
Beni's request, so that mechanical support attachments
are only made on the light guides and not to the
scintillators or the phototube/base.
</p>
<h3><span class="mw-headline"
id="Translation_Tables_for_Scalers">Translation Tables
for Scalers</span></h3>
<p>Beni has a meeting with Justin scheduled for Friday to
discuss how this is to be done.
</p>
<h3><span class="mw-headline"
id="Low_Voltage_Feedback_for_the_Chambers">Low Voltage
Feedback for the Chambers</span></h3>
<p>Beni confirmed with Chris that the feedback system for
regulating low voltage at the distribution box is hooked
up.
</p>
<h3><span class="mw-headline"
id="Lead_Shielding_Alignment">Lead Shielding Alignment</span></h3>
<p>The lead shielding in front of the first MWPC will be
positioned, at the 1 mm level, from a study using rates,
with beam on, of the MWPCs at several positions of the
shield. Position adjustment is done by hand in the Hall,
so Rapid Access will be necessary to carry out the
program. Ilya will draft a run plan for this activity.
</p>
<h3><span class="mw-headline" id="CPP_Trigger_Tests">CPP
Trigger Tests</span></h3>
<p>Sergey reported that the CDC AI tests are done. Sascha
is aware of this and he will start back on trigger
tests. Ben Raydo may have to be pulled in at some point.
Rory emphasized that this is on the critical path.
</p>
<h3><span class="mw-headline"
id="DAQ_and_Electronic_Setup">DAQ and Electronic Setup</span></h3>
<p>Sergey reported that the CDC crate with the FADC-125s
is mounted in its new location for use with the MWPCs. A
new VME computer has been put in the crate. The crate
has no power and it needs a optical fiber for read-out
still.
</p>
<p>[Added in press, from Beni: the VXS crate has now
power. There is also AC 120V regular power available in
the rack.]
</p>
<h3><span class="mw-headline"
id="Tagger_Hodoscope_Location_7">Tagger Hodoscope
Location 7</span></h3>
<p>Mark mentioned that at yesterday's Hall D Staff meeting
Tim Whitlatch mentioned that he was waiting on a
decision from the CPP group on installing a plate, at
location 7, for mounting tagger hodoscope counters. We
think we need this. We will try to clarify the issue at
tomorrow's Design Meeting.
</p>
<p>[Added in press: Mark asked and Sascha agreed to attend
the meeting.]
</p>
<h3><span class="mw-headline" id="CTOF_Trigger">CTOF
Trigger</span></h3>
<p>Rory asked about readiness of the various components
needed to form a trigger from the downstream
scintillators. Beni reported that all the components
were in-hand or easily acquired.
</p>
<ul>
<li> The PMTs have two outputs, one will to the FADCs,
the other to a discriminator</li>
<li> The discriminator has two outputs. One will go to a
CAEN TDC, the other to the trigger logic.</li>
<li> Trigger logic is housed in a NIM crate.</li>
<li> The output of the trigger logic modules is sent
over fiber to the GTP.</li>
</ul>
<h3><span class="mw-headline"
id="Schedule_for_Chamber_Data">Schedule for Chamber
Data</span></h3>
<p>Alex asked about the schedule for reading out the
chambers so that monitoring and reconstruction can start
to be tested. Beni thought that it would be at least
couple of weeks. Not only does the chamber read-out
chain need to be established, but the CTOF trigger has
to be working.
</p>
</div>
<div class="printfooter">
Retrieved from "<a dir="ltr"
href="https://halldweb.jlab.org/wiki/index.php?title=Π_polarizability_Meeting_Mar_23,_2022&oldid=111862">https://halldweb.jlab.org/wiki/index.php?title=Π_polarizability_Meeting_Mar_23,_2022&oldid=111862</a>"</div>
</div>
</div>
</div>
<div id="footer" role="contentinfo">
<ul id="f-list">
<li id="lastmod"> This page was last modified on 23 March
2022, at 21:41.</li>
</ul>
</div>
</div>
</body>
</html>