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Here's a discussion between me and Chris Slominski about using the existing energy locks to lock beam energy in Hall A rather than FFB or the Arc2 energy lock. It's yet another option we can explore for energy stability.</div>
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Dennis<br>
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<div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> Chris Slominski <cjs@jlab.org><br>
<b>Sent:</b> Monday, August 24, 2020 6:33 AM<br>
<b>To:</b> Dennis Turner <dturner@jlab.org><br>
<b>Subject:</b> Re: Thoughts on the energy locks</font>
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<p style="margin-top: 0px; margin-bottom: 0px;">Any BEM measured section could be the source of energy error. The three sets of controls, LINACs, would only be able to be used once per measurement section. Are we confident the Hall A energy error estimated
by BEM is accurate? This could be done before the end of this run.<br>
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<div class="x_moz-cite-prefix">On 8/21/2020 10:16 PM, Dennis Turner wrote:<br>
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Hi Chris,</div>
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There was some discussion earlier today about the recent energy drifts in Hall A. They would normally use either the 2A energy lock or Fast Feedback to lock the beam energy in the hall, but FFB has been exhibiting other undesirable effects, and Arc 2 only
has nA beam until Hall C comes back on line. Would it be possible to use the existing arc energy locks to lock the energy in a hall? The existing arc energy locks look at the BEM signals for the arcs, like ARC1:p and ARC2:p. It seems to me that it wouldn't
be terribly difficult to have additional energy locks for the halls that look at the hall BEM readbacks, like HALLA:p for example. I could imagine some logic that would, for example, exclude using the 2A and a hall to lock energy at the same time. What are
your thoughts on this? <br>
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Dennis<br>
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