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<p class="MsoNormal">Thanks Anu, <o:p></o:p></p>
<p class="MsoNormal">Best regards <o:p></o:p></p>
<p class="MsoNormal">Kondo<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>From:</b> Anuruddha Rathnayake <adr4zs@virginia.edu> <br>
<b>Sent:</b> Sunday, January 30, 2022 6:23 PM<br>
<b>To:</b> Gnanvo, Kondo (kg6cq) <kg6cq@virginia.edu><br>
<b>Cc:</b> Jeffas, Sean (sj9ry) <sj9ry@virginia.edu>; Sbs_gems@jlab.org<br>
<b>Subject:</b> Re: [Sbs_gems] [EXTERNAL] Re: GEM Negative Pulse Overview<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Data acquisition for GEM negative pulse study was just completed.<br>
<br>
Please see the log entry <a href="https://logbooks.jlab.org/entry/3979464">https://logbooks.jlab.org/entry/3979464</a> for the runs taken. I have also updated the SBS RUN LIST spreadsheet.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">Best,<br>
Anu<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Sun, Jan 30, 2022 at 4:45 PM Gnanvo, Kondo (kg6cq) <<a href="mailto:kg6cq@virginia.edu">kg6cq@virginia.edu</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Hi Anu,
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Yes that should be ok. Anytime from now on is fine.
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I just need to inform the shift leader.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Let me know when you are in the CH<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Best regards
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Kondo
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b>From:</b> Anuruddha Rathnayake <<a href="mailto:adr4zs@virginia.edu" target="_blank">adr4zs@virginia.edu</a>>
<br>
<b>Sent:</b> Sunday, January 30, 2022 4:19 PM<br>
<b>To:</b> Gnanvo, Kondo (kg6cq) <<a href="mailto:kg6cq@virginia.edu" target="_blank">kg6cq@virginia.edu</a>><br>
<b>Cc:</b> Jeffas, Sean (sj9ry) <<a href="mailto:sj9ry@virginia.edu" target="_blank">sj9ry@virginia.edu</a>>;
<a href="mailto:Sbs_gems@jlab.org" target="_blank">Sbs_gems@jlab.org</a><br>
<b>Subject:</b> Re: [Sbs_gems] [EXTERNAL] Re: GEM Negative Pulse Overview<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Hi Kondo,<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Since I am on call right now, Ican come in around 5 pm and perform these tests.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Let me know if that is okay with you.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Best,<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Anu<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">On Sun, 30 Jan 2022, 16:12 Gnanvo, Kondo (kg6cq), <<a href="mailto:kg6cq@virginia.edu" target="_blank">kg6cq@virginia.edu</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Hi Sean, Anu
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">We discussed at the RC meeting the afternoon that now (swing or owl shift) is the best time to do the studies that you suggested below.
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I was wondering if you and /or Anu will be able to come in and perform that study. Any time you will want is ok as.
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Sean: On your suggestion below, you wanted to do it with LH2, however we are now taking LD2 data until tomorrow and I assume it is OK to do it with LD2 as well (only to adjust the
beam current accordingly) right? <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">You could sill do 1, 3, 5 and 7 uA on LD2
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Let me know
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Best regards
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Kondo<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b>From:</b> Sbs_gems <<a href="mailto:sbs_gems-bounces@jlab.org" target="_blank">sbs_gems-bounces@jlab.org</a>>
<b>On Behalf Of </b>Sean Jeffas<br>
<b>Sent:</b> Wednesday, January 26, 2022 4:00 PM<br>
<b>To:</b> <a href="mailto:Sbs_gems@jlab.org" target="_blank">Sbs_gems@jlab.org</a><br>
<b>Subject:</b> [Sbs_gems] [EXTERNAL] Re: GEM Negative Pulse Overview<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Hi All,<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Here is my ideas for doing a GEM study on this:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b>For all runs use GM1_Pedestal configuration (full readout, no zero suppression)</b><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b>200k events for all GEMs (should be 3 minutes or less)</b><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">1) 1 uA on LH2 GEMs at operational HV<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">2) 3 uA on LH2 GEMs at operational HV<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">3) 3 uA on LH2 GEMs at 1500 V<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">4) 5 uA on LH2 GEMs at operational HV<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">5) 8 uA on LH2 GEMs at operational HV<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">6) 8 uA on LH2 GEMs at 1500 V<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">7) 8 uA on LH2 GEMs at 0 V<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Overall this should take about 30 minutes of beam time. Please let me know if you have any ideas to change or add something to this.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Best,<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Sean<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">On Wed, Jan 26, 2022 at 1:32 PM Sean Jeffas <<a href="mailto:sj9ry@virginia.edu" target="_blank">sj9ry@virginia.edu</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Hi All,<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I am mostly sending this out because Kondo, Andrew, and Bogdan were not in the GEM meeting today and I overviewed the issue of the negative GEM signals seen in the hall. I have
attached my slides below. <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><a href="https://hallaweb.jlab.org/wiki/images/f/fd/Neg_signal_1_26_22.pdf" target="_blank">https://hallaweb.jlab.org/wiki/images/f/fd/Neg_signal_1_26_22.pdf</a><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><br>
At the meeting Ben suggested one interesting reason for why the CM would decrease at higher currents, but the fraction of negative pulses would also decrease. He suggested that this may happen if the positive signal "overrides" a negative signal on the same
strip. So at higher currents, with higher occupancy, there are less strips with negative signals (because they are already positive), decreasing the fraction, but the negative signals are still used in the CM calculation, causing the decrease in the CM. (Ben,
please correct me if I have not described your idea properly).<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Overall we need more data and analysis to understand this problem. We should decide on a set of quick runs to study the negative pulses more. This will also be simple because Kondo
is RC this week. Kondo has already suggested a test with HV ~1500V and beam on with online zero suppression enabled. I think we should also take some data at different beam currents with nominal HV values and the online zero suppression disabled. This can
be accomplished with 30 minutes of beam time. Please suggest any other ideas for tests with beam.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">For analysis, there are not many options in the analyzer right now to study the negative signals. We only have a few predefined histograms saved for full readout events, but most
of the data is discarded because it is not of interest for the tracking. We will need to add some analysis to store all the strip information to study this properly. Then we can fully see what type of events the negative signals affect on average. We can check
if they show up in patterns of strips on all the APVs, their occupancy, and how they correlate to real signals. Please suggest any other analysis ideas for distributions to check.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Best,<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Sean<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">_______________________________________________<br>
Sbs_gems mailing list<br>
<a href="mailto:Sbs_gems@jlab.org" target="_blank">Sbs_gems@jlab.org</a><br>
<a href="https://mailman.jlab.org/mailman/listinfo/sbs_gems" target="_blank">https://mailman.jlab.org/mailman/listinfo/sbs_gems</a><o:p></o:p></p>
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