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HI Sean,</div>
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No, I think it would be best to run at 3653 V with this modified divider for right now. </div>
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We are going to study the modified divider with the x_ray source here over the new couple of weeks. Once we know more, we can consider going higher if needed</div>
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Best</div>
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Nilanga</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Sbs_gems <sbs_gems-bounces@jlab.org> on behalf of Sean Jeffas <sj9ry@virginia.edu><br>
<b>Sent:</b> Thursday, November 18, 2021 3:22 PM<br>
<b>To:</b> sbs_gems@jlab.org <sbs_gems@jlab.org><br>
<b>Subject:</b> [Sbs_gems] [EXTERNAL] UV GEM HV Settings</font>
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<div dir="ltr">Hi Kondo and Nilanga,
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<div>After we changed the resistor on UV GEM layer 0 back in October Kondo recommended to lower the HV a bit to monitor the GEM HV. Here is the logbook reference <a href="https://logbooks.jlab.org/entry/3930480">https://logbooks.jlab.org/entry/3930480</a>.
However we discovered this week that the voltage has never been returned to 3697 V since then, and we ran all this week at 3653 V. From Kondo's log it is my impression that he meant to only set it to 3653 V for a few hours. Is it ok to change to 3697 V at
this point? Also with the two other UV GEMs in BB we also have these new dividers. Then ran all night at 3653 V with cosmics with no issues. Can we set those to 3697 V as well?</div>
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<div>Best,<br>
Sean</div>
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