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<p class="MsoNormal">Hello all, <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In light of our new reality of the apparent hardware failure of 2/3 of J0 modules, we are back to basically having only 4 good tracking layers in BigBite. Moreover, in light of the fact that we see a significantly more severe gain/efficiency
drop in all the GEMs (except, perhaps, the back tracker) on LH2 at 15 uA than on LD2 at 8 uA, and in light of the fact that the LH2 running is mainly for calibration purposes, I would like to suggest that we back off in beam current for the LH2 running unless
and until we can get a fifth good layer into BigBite again. Moreover, in light of this failure of J0 I would advocate that we stick to being a little bit more conservative in terms of trying to push higher luminosities until the cause and scope of the J0 failure
are better understood. I am cc’ing Bogdan and Brian on this message as spokespeople. We can have a discussion of the idea at the RC meeting this afternoon.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Andrew<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="font-family:"Century",serif;color:black">Andrew Puckett<br>
Associate Professor, Physics Department<br>
University of Connecticut<br>
196 Auditorium Road, Unit 3046<br>
Storrs, CT 06269-3046<br>
Office phone: (860) 486-7137<br>
<a href="https://puckett.physics.uconn.edu/" title="https://puckett.physics.uconn.edu/"><span style="color:#00006A">https://puckett.physics.uconn.edu</span></a><br>
<a href="mailto:puckett@jlab.org" title="mailto:puckett@jlab.org"><span style="color:#000064">puckett@jlab.org</span></a></span><o:p></o:p></p>
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