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Hi All,</div>
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My understanding for the logic of switching from 10% to 20% radiator is as follows (all numbers are approximate; assuming the flux doubles):</div>
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Suppose the photon suppression by the extra 1 cm of tungsten is 50%, and the KL suppression by 1 cm of tungsten is 20%.</div>
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If the largest acceptable photon background for 10% radiator is at 14 cm tungsten, and the KL rate at the HD target is 5 kHz, </div>
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then for 20% radiator and 15 cm tungsten we will have the same photon background, and the rate of KL will be 10 kHz * 0.8 = 8 kHz.</div>
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So there is advantage in increasing the incident photon flux and increasing the tungsten block thickness simultaneously.</div>
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Best regards,</div>
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Pavel</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Halld-klf-beam <halld-klf-beam-bounces@jlab.org> on behalf of Hovanes Egiyan <hovanes@jlab.org><br>
<b>Sent:</b> Tuesday, February 11, 2025 11:12 AM<br>
<b>To:</b> halld-klf-beam@jlab.org <halld-klf-beam@jlab.org><br>
<b>Subject:</b> [Halld-klf-beam] KLF beamline meeting on Thursday, February 13th</font>
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Hi, </div>
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We will have a KLF beamline meeting on Thursday, February 13<sup>th</sup>, at 1:00pm using Zoom (see information below). I posted the preliminary agenda of the meeting on KLF wiki:</div>
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<a href="https://wiki.jlab.org/klproject/index.php/KLF_beamline_meeting_-_February_13,_2025" id="LPlnk624255">https://wiki.jlab.org/klproject/index.php/KLF_beamline_meeting_-_February_13,_2025</a></div>
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Please, feel free to add items to the agenda, or let me know if you would like to discuss a topic. </div>
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Best, </div>
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Hovanes. </div>
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Join ZoomGov Meeting</div>
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<a href="https://jlab-org.zoomgov.com/j/1606674688?pwd=b3dnTzJWVEtxZExGRnFoY29PSGkxQT09" target="_blank" id="OWAcf02508e-bc69-bfe1-eed5-73d8fdf0b2ec" class="x_x_x_x_ms-outlook-linkify x_x_x_x_OWAAutoLink" title="https://jlab-org.zoomgov.com/j/1606674688?pwd=b3dnTzJWVEtxZExGRnFoY29PSGkxQT09" rel="noopener noreferrer" data-auth="NotApplicable" data-linkindex="1" style="margin:0px">https://jlab-org.zoomgov.com/j/1606674688?pwd=b3dnTzJWVEtxZExGRnFoY29PSGkxQT09</a></div>
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Meeting ID: 160 667 4688</div>
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Passcode: 709878</div>
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