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</style>BTeam --<br>
<br>
Now that we're back to steady operations in CEBAF, we should
concentrate on our strategic interests for the remainder of the run.
There is not that much more time before the 6 month SAD, and we
should develop our prioritized lists and study plans to learn what
we need to learn before then. Machine-based optics/magnet
measurements are foremost on my mind; other topics include
motivations for diagnostic improvements. Please bring your ideas and
priorities to the meeting this afternoon, and/or send them to me,
and we'll develop our plans for BTeam for the remainder of this run.
See you there, and thanks!<br>
<br>
-Todd<br>
<h1 class="title">BTeam-2011-02-09</h1>
<div class="outline-2">
<h2 id="sec-1">1 2011-02-09 Wed 14:00 BTeam Meeting Agenda</h2>
<div class="outline-3">
<h3 id="sec-2">1.1 Optics-on-Call Report: Balsa/Alex =>
Shahid/Geoff</h3>
<p>Yet another eventful week with a lot of operations diagnosis
concentrating on the injector. On Friday we fixed the recent
machine
woes with a reduction of GSET on the 0L03-2 cavity in the
injector
to reduce fluttering PASKR (phase loop effort RMS). We have
since
been able to return to stable running conditions for Halls
B/C, and
with the addition of Hall A this week, we should be able to
return
to beam studies that do not involve immediate firefighting to
keep
the operational program on track.
</p>
</div>
<div class="outline-3">
<h3 id="sec-3">1.2 Beam Studies Report</h3>
<div class="outline-4">
<h4 id="sec-4">1.2.1 <span class="done">DONE</span> Injector
optics: Bogacz</h4>
<p>Alex implemented a different injector optics last week,
which
also improved injector performance and reduced some trips in
the middle of the injector chicane where beam sizes had
previously
been high. These optics should now be much closer to the
design
optics, as we also put these optics into the elegant design
baseline.
</p>
</div>
<div class="outline-4">
<h4 id="sec-5">1.2.2 <span class="done">DONE</span> Injector
model: Freyberger</h4>
<p>See above: elegant baseline should now match machine
settings.
</p>
</div>
</div>
<div class="outline-3">
<h3 id="sec-6">1.3 Beam Studies Planning and Discussion</h3>
<div class="outline-4">
<h4 id="sec-7">1.3.1 <span class="todo">TODO</span> Bunch
length measurement: Hofler/Kazimi</h4>
<p>Lack of reliable bunch length measurements seemed to be a
challenge
during the diagnosis of the 0L03-2 problem. The most recent
measurements did not seem correct. Perhaps we should make
sure that this measurement is now reliable and understood.
There is still a beam tail on the 1A SLM but there is no
strong drive to change the injector or try to fix this based
on experiment feedback and Compton/halo backgrounds.
</p>
</div>
<div class="outline-4">
<h4 id="sec-8">1.3.2 <span class="todo">TODO</span> ? Parity
quality improvements from injector coupling: Roblin</h4>
<p><a href="http://cebaf.jlab.org/atlis/task/8346">ATLis 8346</a>:
Some concern that parity quality is marginal for
Qweak. We should check that the injector skew correctors
were
scaled properly for the gun HV/energy changes during our
optics
fixes on 2011-02-03, and, if not, perhaps scaling them will
improve Qweak parity quality with little impact. A
measurement
and retune, such as this ATLis from Yves, is fairly
invasive.
</p>
</div>
<div class="outline-4">
<h4 id="sec-9">1.3.3 <span class="todo">TODO</span> ? LOCO
Model Calibration Tests: Roblin (~2h)</h4>
<p><a href="http://cebaf.jlab.org/atlis/task/10700">ATLis
10700</a>: Measured, but BPM problems in center of arc.
Yves reported last week. Have some analysis upstream and
downstream
of affected mux, but should restore good BPM behavior and
remeasure.
Being worked on, will not ask for more time until sorted
out.
Noisy BPMs were vertical? Tief investigating, noted
horizontal noise.
</p>
</div>
<div class="outline-4">
<h4 id="sec-10">1.3.4 <span class="todo">TODO</span> ?
RayTrace in ARC3: Bodenstein (~30min)</h4>
<p><a href="http://cebaf.jlab.org/atlis/task/10708">ATLis
10708</a>: See above, should redo with LOCO model
remeasurement.
</p>
</div>
</div>
<div class="outline-3">
<h3 id="sec-11">1.4 AOB?</h3>
<p>
======================================================================
</p>
</div>
</div>
<div class="outline-2">
<h2 id="sec-12">2 2011-02-02 Wed 14:00 BTeam Meeting Agenda</h2>
<div class="outline-3">
<h3 id="sec-13">2.1 Optics-on-Call Report: Byung/Yves =>
Balsa/Alex</h3>
<p>This has been a very eventful week with serious struggles to
get high
current operations back to hall C (1) and parity quality beam
back to
hall B (5) yet again. Optics have investigated injector optics
and
assisted with an observation of asymmetric quad settings in
the
injector chicane. Restoration of injector chicane quad
symmetry
helped restore high current beam operations on Mon 1/31 before
it was again lost during gun HV=>130kV on Tue 2/1.
</p>
<p>
The majority of the BTeam meeting this week will focus on
ideas for
diagnosing the Hall C high current problem and restoring high
current
operations to Hall C. We are committed to moving forward with
the
130 kV injector gun HV.
</p>
<p>
Upon restoration of routine high intensity operations, Hall C
will
likely want a spin dance (or mini-spin dance) and Compton
cleanup,
but these are second order compared to the first order problem
of
restoring reliable high-quality high-intensity beam.
</p>
<div class="outline-4">
<h4 id="sec-14">2.1.1 <span class="todo">TODO</span> Injector
optics: Bogacz</h4>
<p>Alex has different injector optics to discuss, and believes
that the
injector chicane quadrupole change on Monday is perhaps only
the
start of needed injector optics changes.
(see hand notes)
</p>
</div>
</div>
<div class="outline-3">
<h3 id="sec-15">2.2 Beam Studies Report</h3>
<div class="outline-4">
<h4 id="sec-16">2.2.1 <span class="done">DONE</span>? 5s
Motion In Injector From Polling: Suleiman/Higgins (~1h)</h4>
<p><a href="https://cebaf.jlab.org/atlis/task/10739">ATLis
10739</a>: Done AM Wed 2011-01-26, confirmed polling/vert
motion
correlation. Polling left off after study. Was originally
observed
about 1y ago. Seems to be someting within controls, as all
polled
items are downstream of first observed BPM 5s motion. Still
noting
1s intermittent motion. Vector voltmeters entirely
disconnected
on 2011-02-01.
</p>
</div>
</div>
<div class="outline-3">
<h3 id="sec-17">2.3 Beam Studies Planning and Discussion</h3>
<div class="outline-4">
<h4 id="sec-18">2.3.1 <span class="todo">TODO</span> Injector
optics: Bogacz</h4>
<p>Alex has different injector optics to discuss, and believes
that the
injector chicane quadrupole change on Monday is perhaps only
the
start of needed injector optics changes.
(see hand notes)
</p>
</div>
<div class="outline-4">
<h4 id="sec-19">2.3.2 <span class="todo">TODO</span> Injector
model: Freyberger</h4>
<p>The injector model is far from design and not correct right
now,
complicating comparisons to "design". How do we establish a
good
baseline injector model for the present machine
configuration?
</p>
<p>
Discussion of Alex's talk seems to address this question as
well.
</p>
</div>
<div class="outline-4">
<h4 id="sec-20">2.3.3 <span class="todo">TODO</span> Bunch
length measurement: Hofler/Kazimi</h4>
<p>Part of our problem is related to anomalous beam profiles
as far
back as Inj and arc 1 SLMs. Inj SLM is round, whereas design
has
a 1:3 x:y size ratio. Arc 1 SLM has two low energy tails
that
rotate with NL gang and individual cavity phases. NL
individual
cavity phasing did not improve this profile. This seems to
suggest
a bunch length issue.
</p>
<p>
Joe suggested that we calibrate the Hall C slit and close it
up
a bit to improve Hall C beam quality. This may tell us
something
about upstream timing/bunch length but may also make us more
sensitive to upstream changes.
</p>
</div>
</div>
<div class="outline-3">
<h3 id="sec-21">2.4 Bunch length team meeting report:
Kazimi/Hofler</h3>
<ul>
<li><span class="done">DONE</span> : Bunch length group
meeting (Reza, Alicia, Tief)<br>
Can we make bunch length phase configurations SW config
files?
Done, very informally; discussed need for assembling tools.
Can measure real-time bunch length with running 1-2 deg off
crest
in compensating directions in both linacs, assuming we can
get
back to that setup with high energy. Will discuss further.
</li>
</ul>
</div>
<div class="outline-3">
<h3 id="sec-22">2.5 12GeV Pathlength Requirements Status:
Tiefenback</h3>
<div class="outline-4">
<h4 id="sec-23">2.5.1 <span class="todo">TODO</span> Need
conclusions document.</h4>
<p>In process.
</p>
</div>
</div>
<div class="outline-3">
<h3 id="sec-24">2.6 AOB?</h3>
</div>
</div>
<div id="postamble">
<p class="author"> Author: Todd Satogata
<a href="mailto:satogata@Todd-Satogatas-MacBook-Pro.local"><satogata@Todd-Satogatas-MacBook-Pro.local></a>
</p>
<p class="date"> Date: 2011/02/09 12:32:15</p>
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