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<div class="">Dear GlueX Collaborators,<br class="">
<br class="">
As discussed today during the RC meeting, the accelerator has recently encountered several problems (see below Arne's email - kindly forwarded by Alexandre - for a detailed explanation of the status). </div>
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<div class="">In light of this, shifts are canceled up to next Friday, 8am. </div>
<div class="">The next RC meeting will be on Tuesday, September 4, usual time. </div>
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<div class="">Thanks,</div>
<div class="">—Cristiano, RC</div>
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<div class="">----- Forwarded Message -----<br class="">
<blockquote type="cite" class="">From: "Arne Freyberger" <<a href="mailto:freyberg@jlab.org" class="">freyberg@jlab.org</a>><br class="">
To: "Bob McKeown" <<a href="mailto:bmck@jlab.org" class="">bmck@jlab.org</a>>, "Rolf Ent" <<a href="mailto:ent@jlab.org" class="">ent@jlab.org</a>>, "rossi patrizia" <<a href="mailto:rossi@jlab.org" class="">rossi@jlab.org</a>>, "Javier Gomez"<br class="">
<<a href="mailto:gomez@jlab.org" class="">gomez@jlab.org</a>>, "Mary Logue" <<a href="mailto:logue@jlab.org" class="">logue@jlab.org</a>>, "Bob May" <<a href="mailto:may@jlab.org" class="">may@jlab.org</a>>, "Will Oren" <<a href="mailto:oren@jlab.org" class="">oren@jlab.org</a>>,
"Rusty Sprouse"<br class="">
<<a href="mailto:sprouse@jlab.org" class="">sprouse@jlab.org</a>>, "Michael Maier" <<a href="mailto:mmaier@jlab.org" class="">mmaier@jlab.org</a>>, "Allison Lung" <<a href="mailto:lung@jlab.org" class="">lung@jlab.org</a>>, "Stuart Henderson"<br class="">
<<a href="mailto:stuart@jlab.org" class="">stuart@jlab.org</a>>, "Lauren Hansen" <<a href="mailto:lhansen@jlab.org" class="">lhansen@jlab.org</a>>, "Mike Spata" <<a href="mailto:spata@jlab.org" class="">spata@jlab.org</a>>, "Andrei Seryi" <<a href="mailto:seryi@jlab.org" class="">seryi@jlab.org</a>>,<br class="">
"burkert" <<a href="mailto:burkert@jlab.org" class="">burkert@jlab.org</a>>, "Eugene Chudakov" <<a href="mailto:gen@jlab.org" class="">gen@jlab.org</a>>, "Cynthia Keppel" <<a href="mailto:keppel@jlab.org" class="">keppel@jlab.org</a>><br class="">
Cc: "Latifa Elouadrhiri" <<a href="mailto:latifa@jlab.org" class="">latifa@jlab.org</a>>, "Dave Mack" <<a href="mailto:mack@jlab.org" class="">mack@jlab.org</a>>, "Alexandre Deur" <<a href="mailto:deurpam@jlab.org" class="">deurpam@jlab.org</a>>, "Steven<br class="">
Suhring" <<a href="mailto:Suhring@jlab.org" class="">Suhring@jlab.org</a>><br class="">
Sent: Friday, August 31, 2018 9:22:20 AM<br class="">
Subject: CEBAF Status: No beam for at least a week<br class="">
</blockquote>
<br class="">
<blockquote type="cite" class="">Not much new information on the source of the North linac vacuum leak.<br class="">
<br class="">
Yesterday clean rooms were installed on two girders in the North linac<br class="">
and prepared (made clean) for today's connection to the beamline.<br class="">
Leak checking will start soon after the connection is made.<br class="">
<br class="">
In parallel, the five modules (NL21-NL25) of the North linac will be<br class="">
warmed up over the weekend. This warm-up is needed to release frozen<br class="">
gases on the beamline surfaces. It will also "ready" these modules for<br class="">
extensive leak checking if the leak is not in the warm section between<br class="">
the cryomodules. Best case is that the leak is identified and repaired<br class="">
in a warm girder early next week (perhaps even today), followed by<br class="">
cooling down the warmed up modules next week. This *may* put us in a<br class="">
position to deliver beam by next Friday.<br class="">
<br class="">
If the leak is found to be within a cryomodule, it will have to be<br class="">
removed and replaced with one of the modules removed during the<br class="">
Summer. This would also mean that another week of delay in the<br class="">
startup. Enough information to make a decision on removing a module<br class="">
(or not) will be available in the next several days.<br class="">
<br class="">
The Halls run coordinators were informed this morning to cancel shifts<br class="">
up to next Friday.<br class="">
<br class="">
Arne<br class="">
<br class="">
--<br class="">
Arne Freyberger<br class="">
Director of Accelerator Operations<br class="">
Jefferson Lab Office: (757) 269-6289<br class="">
12000 Jefferson Avenue Cell: (757) 876-6289<br class="">
Newport News, VA 23606 Email: <a href="mailto:freyberg@jlab.org" class="">freyberg@jlab.org</a></blockquote>
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