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FYI</div>
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I presume BTeam has been pondering the results of tests and analysis.</div>
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<span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background: var(--white);">Talk to you tomorrow,</span></div>
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<span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background: var(--white);">HyeKyoung </span></div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> mhattawy@odu.edu <mohammad.hattawy@gmail.com><br>
<b>Sent:</b> Thursday, August 27, 2020 6:21 PM<br>
<b>To:</b> Brian Freeman <bfreeman@jlab.org>; HyeKyoung Park <hkpark@jlab.org>; Stepan Stepanyan <stepanya@jlab.org>; Kuhn, Sebastian E. <skuhn@odu.edu>; Paul Vasilauskis <vasilaus@jlab.org>; Mike Spata <spata@jlab.org><br>
<b>Subject:</b> [EXTERNAL] Follow up on Hall B Halo Rates Troubleshooting</font>
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<div>Dear HyeKyoung and all,<br>
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<div> Following up on the effort of understating the rates increase we see in Hall B and the logbook entry from Brian
<a href="https://logbooks.jlab.org/entry/3835655">https://logbooks.jlab.org/entry/3835655</a>. Brian reported on checking the laser phase on FC and the sensitivity to the 2C09 position. Unfortunately, we did not improve the situation and the rates are still
increasing forcing me to reduce the beam current to 170 nA (from 180 nA). <br>
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<div>Brian mentioned additional possible tests in his summary: <br>
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<div>1. Check/ Recheck all Separation.<br>
2. Check background relative to pre-buncher settings.<br>
3. Test the sensitivity to Quad changes.</div>
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<div>I would like to ask Brian if he can provide a time estimate for these additional tests and I would like to ask you if you can provide the manpower to continue this investigation tomorrow at the beginning of the day shift.
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<div dir="ltr" class="x_gmail_signature">Best regards,<br>
Mohammad Hattawy.<br>
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