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Great Jay,</div>
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<span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">First hand look and my initial thoughts...!</span><br>
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<li style="list-style-type: "1. ";"><span>10 A/mm^2 is not bad...</span></li><li style="list-style-type: "2. ";"><span>1.8 T seems optimistic, what impact does this have to physics with 1.7T ?</span></li><li style="list-style-type: "3. ";"><span>What are the space constraint(s)/limitations...?</span></li><li style="list-style-type: "4. "; font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; color: rgb(0, 0, 0);">
What are the operating <span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; color: rgb(0, 0, 0);">
conditions</span><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"> viz
</span><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; color: rgb(0, 0, 0);">environment</span><span style="font-family: Aptos, Aptos_EmbeddedFont, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"> (temperature)</span></li></ol>
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<span>Regards</span></div>
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<span>Probir</span></div>
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<div><strong>Probir K Ghoshal</strong>, PhD.<br>
Magnet Group Leader, Experimental Nuclear Physics<br>
<em>Jefferson Lab<br>
600 Kelvin Drive, Suite #3, 55C<br>
Room #2545, Newport News, VA 23606 (USA)</em><br>
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Telephone: 757 269 6702 (office)<br>
Mobile: 518 334 3289<br>
email: ghoshal@jlab.org</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> PEPPo <peppo-bounces@jlab.org> on behalf of Jay Benesch via PEPPo <peppo@jlab.org><br>
<b>Sent:</b> Thursday, October 12, 2023 10:10 AM<br>
<b>To:</b> peppo@jlab.org <peppo@jlab.org><br>
<b>Subject:</b> [PEPPo] positron capture magnet</font>
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<div class="PlainText">I did a quick and dirty model of a water cooled copper capture solenoid
<br>
30 cm long with 30 cm IR and steel outside 20 cm IR. In order to get <br>
1.8 T peak I had to increase the current density to unacceptable levels <br>
with 10 cm radial extent so that is 24 cm in the attached. Current <br>
density 1000 A/cm^2 in coil pack, that in the copper will be larger. <br>
Steel is 15 cm thick and still well into saturation. There's a 1 cm gap <br>
between coil and steel. Field at [0.0,-50] 1260 G, about a fifth of <br>
what Andriy showed. Default "good magnet steel" BH curve used. Field <br>
will be a few percent lower if 6" cold rolled steel of easily available <br>
grade is used.</div>
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