<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=ISO-8859-1">
</head>
<body>
<title>BTeam-2011-02-02</title>
<meta http-equiv="Content-Type" content="text/html;
charset=ISO-8859-1">
<meta name="generator" content="Org-mode">
<meta name="generated" content="2011/02/02 13:03:45">
<meta name="author" content="Todd Satogata">
<style type="text/css">
html {
font-family: Times, serif;
font-size: 12pt;
}
.title { text-align: center; }
.todo { color: red; }
.done { color: green; }
.timestamp { color: grey }
.timestamp-kwd { color: CadetBlue }
.tag { background-color:lightblue; font-weight:normal }
.target { background-color: lavender; }
pre {
border: 1pt solid #AEBDCC;
background-color: #F3F5F7;
padding: 5pt;
font-family: courier, monospace;
}
table { border-collapse: collapse; }
td, th {
vertical-align: top;
<!--border: 1pt solid #ADB9CC;-->
}
</style>BTeam -<br>
<br>
Here is an agenda for this afternoon's BTeam meeting. It will almost
entirely focus on<br>
the tactical issue at hand, namely how to diagnose the current
machine problems and<br>
restore reliable 150+ uA beam to Hall C with the 130 kV injector gun
HV setup. Please<br>
bring your ideas and your open minds so we can come up with some
recommendations<br>
for tuning for tomorrow to stabilize for the weekend.<br>
<br>
Apologies for the lateness of this email -- it's been one of those
weeks. Thanks!<br>
<br>
-Todd<br>
<br>
<h1 class="title">BTeam-2011-02-02</h1>
<div class="outline-2">
<h2 id="sec-1">1 2011-02-02 Wed 14:00 BTeam Meeting Agenda</h2>
<div class="outline-3">
<h3 id="sec-2">1.1 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>
<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>? 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-5">1.3 Beam Studies Planning and Discussion</h3>
<div class="outline-4">
<h4 id="sec-6">1.3.1 <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.
</p>
</div>
<div class="outline-4">
<h4 id="sec-7">1.3.2 <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>
</div>
<div class="outline-4">
<h4 id="sec-8">1.3.3 <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-9">1.4 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-10">1.5 12GeV Pathlength Requirements Status:
Tiefenback</h3>
<div class="outline-4">
<h4 id="sec-11">1.5.1 <span class="todo">TODO</span> Need
conclusions document.</h4>
<p>In process.
</p>
</div>
</div>
<div class="outline-3">
<h3 id="sec-12">1.6 AOB?</h3>
<p>
======================================================================
</p>
</div>
</div>
<div class="outline-2">
<h2 id="sec-13">2 2011-01-26 Wed 14:00 BTeam Meeting Agenda</h2>
<div class="outline-3">
<h3 id="sec-14">2.1 Optics-on-Call Report: Yuhong/Tief =>
Byung/Yves</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). Injector loss trips at 0R04 have limited us to
<100uA at
hall C often, with hour-timescale drifts away whenever
retuned.
</p>
<p>
What other options are on the table should today fail?
</p>
<ul>
<li>
Going to higher gun voltage (130 kV), "A long 8 hours" of
effort
</li>
<li>
Tief: Double up lasers (but only works until A comes on)
</li>
<li>
If beam restore is successful, plan for collimator scan
(~4h)
and mini-spin-dance Thursday to prep for weekend
</li>
</ul>
</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.
</p>
</div>
<div class="outline-4">
<h4 id="sec-17">2.2.2 <span class="done">DONE</span>? LOCO
Model Calibration Tests in ARC3: Roblin (~2h) Tue 2011-01-18</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-18">2.2.3 <span class="done">DONE</span>?
RayTrace in ARC3: Bodenstein (~30min) Tue 2011-01-18</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 class="outline-4">
<h4 id="sec-19">2.2.4 Double peaks in dispersive hall C BPMs:
Benesch</h4>
<p><a
href="http://opweb.acc.jlab.org/CSUEApps/elog/entry/1562549">elog
entry</a>: The differential (xdiff and ydiff) plots are
differences between helicity states. Nothing in ydiff. xdiff
shows
something in 3C11 and 3C12 but not 3C14. Strange since
dispersion
at 3C11=3C14. ypos (position) shows double peaks at 3P03A
and
asymmetry at 3P02A. xpos shows the same. xpos DOESN'T show
anything at 3C12. From a couple weeks ago, will revisit in
newer
logs once we get reliable beam back to Hall C.
</p>
</div>
<div class="outline-4">
<h4 id="sec-20">2.2.5 Bunch length/energy spread measurements:
Tief</h4>
<p>Recommends SLM tail investigation to investigate bunching
process.
Hall B/2C20 SLM was showing nasty profiles last week, for
instance.
Reza is working on the bunch length measurement at present
Wed 2011-01-26.
</p>
<p>
Should we have to keep running off crest? We shouldn't have
to.
</p>
</div>
</div>
<div class="outline-3">
<h3 id="sec-21">2.3 Beam Studies Planning</h3>
<div class="outline-4">
<h4 id="sec-22">2.3.1 <span class="todo">TODO</span>
Backphasing Bunch Length Measurement @100kV: Hofler (2-3h)</h4>
<p><a href="https://cebaf.jlab.org/atlis/task/10684">ATLis
10684</a>: Should be measured again before we leave 100 kV
injector voltage. We do not have a working bunchlength
measurement
at 100 kV at present. IHA4D00 harp repaired Tue 2011-01-25 (<a
href="https://cebaf.jlab.org/atlis/task/10703">ATLis 10703</a>)
so measurement should be feasible. This may be a higher
priority
depending on status of injector reconfiguration Wed
2011-01-26
if we shift to 130 kV injector setup on Thu 2011-01-27. Yves
wants
to be paged along with Alicia for this measurement.
</p>
</div>
<div class="outline-4">
<h4 id="sec-23">2.3.2 <span class="todo">TODO</span> Return
to Arc 1/2 New Optics: Arne (~2-4h)</h4>
<p><a href="https://cebaf.jlab.org/atlis/task/10652">ATLis
10652</a>: Attempted earlier in January. Want to put this
in and
leave it in after a clean ORFP.
</p>
</div>
<div class="outline-4">
<h4 id="sec-24">2.3.3 <span class="todo">TODO</span>
Determine multiharp masking requirements in tune/CW: Benesch</h4>
<p><a href="https://cebaf.jlab.org/atlis/task/10647">ATLis
10647</a>: New ATLis, not scheduled yet. Mainly hall C.
</p>
</div>
<div class="outline-4">
<h4 id="sec-25">2.3.4 <span class="todo">TODO</span> Test
Hall C Energy Measurement Tool: Keesee/Wang (~1.5h)</h4>
<p><a href="https://cebaf.jlab.org/atlis/task/7493">ATLis 7493</a>:
Old ATLis for new Hall C energy measurement tool. Some
work needed on analysis. Should be done before 6mo SAD.
</p>
</div>
<div class="outline-4">
<h4 id="sec-26">2.3.5 <span class="todo">TODO</span> Hall B
PSS BCM Calibration: Mahoney</h4>
<p><a href="https://cebaf.jlab.org/atlis/task/10533">ATLis
10533</a>: Needs up to 500 nA CW to Hall B. Deferred due
to
present Hall B current limit.
</p>
</div>
</div>
<div class="outline-3">
<h3 id="sec-27">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>
Is this necessary after 2011-01-26 injector reconfiguration?
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-28">2.5 12GeV Pathlength Requirements Status:
Tiefenback</h3>
<div class="outline-4">
<h4 id="sec-29">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-30">2.6 AOB?</h3>
<div class="outline-4">
<h4 id="sec-31">2.6.1 <span class="todo">TODO</span>: Qweak
injector voltage 100 kV ok? Or do we move to 130 kV?</h4>
<p>Note that we also need good parity quality with high
current.
</p>
</div>
</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: 2011/02/02 13:03:45</p>
</div>
</body>
</html>