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I <b>almost</b> agree with Richard's interpretation. I think it is
important to measure at least a limited map at 2 extreme excitations
(say 0.9 and 1.7 Tesla) and check (promptly) that the actual
saturation effects are consistent with the Tosca predictions --
leaving open the possibility of more extensive mapping if we find
significant differences.<br>
Dan<br>
<br>
<br>
<div class="moz-cite-prefix">On 8/14/2013 5:53 PM, Richard Jones
wrote:<br>
</div>
<blockquote cite="mid:CABfxa3TTXOONeL4TPFk6KOST8FBnDbZiFFk0srZZQN8m3PU8nw@mail.gmail.com" type="cite">
<div dir="ltr">Hello all,
<div><br>
</div>
<div>I have posted what I think will be the final draft of Dan's
raytracing study through the tagger magnet. Based on these
studies, it seems that mapping the field at any other than the
nominal excitation will not be necessary. In addition to the
regular grid within a region centered on the magnetic poles,
Dan recommends that zones around the beam entrance and exit
regions, and also along the far edge of the pole, be measured
with extended scans. Please see the updated documents on the
wiki for details.</div>
<div>
<div>
<ol>
<li>go to "photon beam" (right menu on the main page of <a href="http://wiki.gluex.org">wiki.gluex.org</a>)</li>
<li>go to "tagger" (right menu item near the top)</li>
<li>to to "plan for mapping the tagger magnet"</li>
<li>see the top two links and the accompanying figure on
this page.</li>
</ol>
<div>We will discuss these results at the next beamline
meeting, but basically the mapping requirements are less
demanding than we had earlier imagined.</div>
<div><br>
</div>
<div>-Richard J.</div>
</div>
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<div class="gmail_extra"><br>
<br>
<div class="gmail_quote">On Wed, Aug 14, 2013 at 3:46 PM, Daniel
Sober <<a href="mailto:sober@cua.edu">sober@cua.edu</a>>
wrote:<br>
<blockquote class="gmail_quote">
<div bgcolor="#FFFFFF" text="#000000"> I think I have
finally solved the Tosca coordinate system problem, which
allowed me to make a more meaningful comparison with the
"standard rays" used in layout work. The results are now
in Section 3 of the updated version of the report, posted
at the same location as previously:<br>
<br>
<a href="http://faculty.cua.edu/sober/HallD/raytracing_studies.pdf">http://faculty.cua.edu/sober/HallD/Raytracing_studies.pdf</a>
.<font color="#888888"><br>
<br>
<div>-- <br>
<font color="#ff0000"><i>Daniel Sober<br>
Professor<br>
Physics Department<br>
The Catholic University of America<br>
Washington, DC 20064<br>
Phone: <a href="tel:%28202%29%20319-5856">(202)
319-5856</a>, -5315<br>
E-mail: <a href="mailto:sober@cua.edu">sober@cua.edu</a></i></font><br>
</div>
</font></div>
<br>
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</blockquote>
</div>
<br>
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</blockquote>
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