[Sbs_gems] [Revised Logentry] SBS GEM HV Issue

[jeffas at jlab.org]

Logentry Text:
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I noticed that two SBS GEM voltages started drifting. See the attached plots below. These two GEMs are physically next to each other on the HV power supply and on the detector stack. You can see that M0 drifts down while M1 drifts up. At some point M1 trips. Then I try to turn it back on and it goes back to drifting upward again. Then I try turning off HV on both modules, and M1 turns off but M0 refuses to turn off and continues drifting. I turned all of SBS GEMs off and you can see in run 4173 that M0 is clearly still on, https://logbooks.jlab.org/entry/4131954 (also look at the plot below. For now I will leave M0 and M1 off ad keep all other SBS GEMs on.

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This is a plain text email for clients that cannot display HTML.  The full logentry can be found online at https://logbooks.jlab.org/entry/4131946
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