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Hi Andrew,</div>
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The key is the electron-nucleon luminosity: the GEn will be effectively about 0.5 uA beam on GMn target even without any collimations. <span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;">So, just use the observed
rate (8 uA SBS-8 with BB at 26.5 degree) and scale the distance/angle.</span></div>
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Bogdan</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Andrew Puckett <puckett@jlab.org><br>
<b>Sent:</b> Thursday, March 3, 2022 2:40 PM<br>
<b>To:</b> Mark Jones <jones@jlab.org>; Bogdan Wojtsekhowski <bogdanw@jlab.org>; Holly Szumila-Vance <hszumila@jlab.org>; Sbs_gems@jlab.org <Sbs_gems@jlab.org><br>
<b>Cc:</b> Cates, Gordon D (gdc4k) <gdc4k@virginia.edu>; Averett, Todd D <tdaver@wm.edu><br>
<b>Subject:</b> Re: Timeline for SBS GEMs</font>
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<p class="x_MsoNormal">One more thing I should add to this is that we do not yet know for certain that the rates on the SBS side will be low, if there is no end window collimation on the SBS side of the beamline. GEMs in SBS was of course not in the original
scope of GEN, and we never simulated having GEMs in SBS under the GEN-II conditions. We can try to look at that, but that would take some work by Eric or someone else. Naively I expect they will be manageable. They will be at forward angle but at larger distance
from the target. If someone can give me even rough information about the geometry of the planned layout of GEMs in SBS, we can certainly simulate the worst-case scenario (with no end window collimation).
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<p class="x_MsoNormal">Andrew </p>
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<p class="x_MsoNormal" style="margin-bottom:12.0pt"><b><span style="font-size:12.0pt; color:black">From:
</span></b><span style="font-size:12.0pt; color:black">Sbs_gems <sbs_gems-bounces@jlab.org> on behalf of Mark Jones <jones@jlab.org><br>
<b>Date: </b>Thursday, March 3, 2022 at 2:32 PM<br>
<b>To: </b>Bogdan Wojtsekhowski <bogdanw@jlab.org>, Holly Szumila-Vance <hszumila@jlab.org>, Sbs_gems@jlab.org <Sbs_gems@jlab.org><br>
<b>Cc: </b>Cates, Gordon D (gdc4k) <gdc4k@virginia.edu>, Averett, Todd D <tdaver@wm.edu><br>
<b>Subject: </b>Re: [Sbs_gems] Timeline for SBS GEMs</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">Bogdan,</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black"> We need to be realistic. I know that you want to run pion A_LL.</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">The estimated schedule has been vetted by Gordon and other target experts</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">and the end of installation by the end of August in realistic. I do not see starting experiment</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">in July as remotely possible.</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black"> We should have a separate meeting to determine what SBS GEMs are a priority to install.</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black"> </span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">Cheers,</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black"> Mark</span></p>
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<p class="x_MsoNormal"><b><span style="color:black">From:</span></b><span style="color:black"> Sbs_gems <sbs_gems-bounces@jlab.org> on behalf of Bogdan Wojtsekhowski <bogdanw@jlab.org><br>
<b>Sent:</b> Thursday, March 3, 2022 2:22 PM<br>
<b>To:</b> Holly Szumila-Vance <hszumila@jlab.org>; Sbs_gems@jlab.org <Sbs_gems@jlab.org><br>
<b>Cc:</b> Cates, Gordon D (gdc4k) <gdc4k@virginia.edu>; Averett, Todd D <tdaver@wm.edu><br>
<b>Subject:</b> Re: [Sbs_gems] Timeline for SBS GEMs</span> </p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">Hi Holly,</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black"> </span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">I would like to bring your attention that with He-3 target the rates will be low and</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">needs for improved (final) HV system is not critical. It would be nice to have one-two </span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">divider to be installed for test.</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">At the same time to make the DAQ installation and commissioning must to be considered. </span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">From GEn point of view I advocate to move GEM installation as early as possible</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">because to start experiment in July is very important.</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">Thanks,</span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black"> </span></p>
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<p class="x_MsoNormal"><span style="font-size:12.0pt; color:black">Bogdan</span></p>
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<p class="x_MsoNormal"><b><span style="color:black">From:</span></b><span style="color:black"> Sbs_gems <sbs_gems-bounces@jlab.org> on behalf of Holly Szumila-Vance <hszumila@jlab.org><br>
<b>Sent:</b> Thursday, March 3, 2022 1:59 PM<br>
<b>To:</b> Sbs_gems@jlab.org <Sbs_gems@jlab.org><br>
<b>Subject:</b> [Sbs_gems] Timeline for SBS GEMs</span> </p>
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<p class="x_MsoNormal">Hi all,<br>
<br>
So it looks like first week of June is still the best time for the crane in Hall A to put the SBS side GEMs in place. We basically have up until then to prepare the layers, and if we are only modifying 1 HV divider then it seems doable to me.
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<br>
We would want the INFN layers modified by then if possible.<br>
<br>
Let me know if you think differently.<br>
<br>
-Holly<br>
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