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Hi Scott,</div>
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You said something interesting during the meeting I did not quite hear as the audio was going in and out at my end.</div>
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I think you said to Donish that to understand how to keep the twiss/dispersion parameters constant while trying to</div>
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set the R56 to what one wants. You described to consider the matrix equation:</div>
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D<b>x</b> = <b>b</b></div>
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<b><br>
</b></div>
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where <b>x</b> is the vector of quad strengths, <b>b</b> is the vector of beta functions/dispersion and you want to find the linear combinations</div>
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of quad strengths that don't change the vector <b>b. </b>I think you are searching for the null space of D (the matrix of derivatives) which</div>
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can be found using SVD of the matrix D assumed to not be of full rank. Anyway, that was my interpretation of what I partially heard</div>
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you say but I think you used a different algorithm to obtain the null space.</div>
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Is this the correct interpretation of what you said?</div>
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Thanks,</div>
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Nick</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> FFA_CEBAF_Collab <ffa_cebaf_collab-bounces@jlab.org> on behalf of Brooks, Stephen via FFA_CEBAF_Collab <ffa_cebaf_collab@jlab.org><br>
<b>Sent:</b> Friday, April 4, 2025 12:09 PM<br>
<b>To:</b> Alex Bogacz via FFA_CEBAF_Collab <ffa_cebaf_collab@jlab.org>; Ryan Bodenstein <ryanmb@jlab.org><br>
<b>Subject:</b> [FFA_CEBAF_Collab] [EXTERNAL] Re: FFA@CEBAF WG mtg. this Friday, April 4</font>
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<div class="BodyFragment"><font size="2"><span style="font-size:11pt;">
<div class="PlainText">Sorry I was in a project review for a different FFA(!)<br>
<br>
-Stephen<br>
<br>
________________________________________<br>
From: FFA_CEBAF_Collab <ffa_cebaf_collab-bounces@jlab.org> on behalf of Ryan Bodenstein via FFA_CEBAF_Collab <ffa_cebaf_collab@jlab.org><br>
Sent: 04 April 2025 12:08<br>
To: Alex Bogacz via FFA_CEBAF_Collab<br>
Subject: Re: [FFA_CEBAF_Collab] FFA@CEBAF WG mtg. this Friday, April 4<br>
<br>
Dear Colleagues,<br>
<br>
Thanks for the good discussion!<br>
<br>
Attached are the minutes.<br>
<br>
Cheers!<br>
Ryan<br>
<br>
From: FFA_CEBAF_Collab <ffa_cebaf_collab-bounces@jlab.org> on behalf of Alex Bogacz via FFA_CEBAF_Collab <ffa_cebaf_collab@jlab.org><br>
Date: Monday, March 31, 2025 at 5:54 PM<br>
To: Alex Bogacz via FFA_CEBAF_Collab <ffa_cebaf_collab@jlab.org><br>
Subject: [FFA_CEBAF_Collab] FFA@CEBAF WG mtg. this Friday, April 4<br>
<br>
Dear Colleagues,<br>
We will continue our design efforts this Friday, April 4, at 11:00 am.<br>
<br>
* Splitter design, update - Donish<br>
* AOB - ALL<br>
Please, follow a ZOOM invitation below.<br>
Cheers,<br>
Alex<br>
___________________________________<br>
S. Alex Bogacz,<br>
Accelerator Physics Group Leader<br>
Center for Advanced Studies of Accelerators<br>
Jefferson Lab<br>
<br>
ZOOM connection:<br>
<br>
The link is here: <a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__jlab-2Dorg.zoomgov.com_j_1614898082-3Fpwd-3DTnUzMS81M2sxbDZIbERJU01tYkJCQT09&d=DwIGaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=Ogg4WFNBwvADBq3fkmCLiJ7SaRDPYtawHzJElJMB0jE&m=te-lLg-vSoDwMBjseLUaw3xcu5jYz_Ny2M_wPF-XRVjsU8ew333N0xZUJYc3Tyxf&s=YoiFqr2WlLAR-C_sjdSO0tKTuWhfq-X7S3CyO19BDuc&e=">
https://urldefense.proofpoint.com/v2/url?u=https-3A__jlab-2Dorg.zoomgov.com_j_1614898082-3Fpwd-3DTnUzMS81M2sxbDZIbERJU01tYkJCQT09&d=DwIGaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=Ogg4WFNBwvADBq3fkmCLiJ7SaRDPYtawHzJElJMB0jE&m=te-lLg-vSoDwMBjseLUaw3xcu5jYz_Ny2M_wPF-XRVjsU8ew333N0xZUJYc3Tyxf&s=YoiFqr2WlLAR-C_sjdSO0tKTuWhfq-X7S3CyO19BDuc&e=</a>
<<a href=""></a>https://urldefense.com/v3/__https://jlab-org.zoomgov.com/j/1614898082?pwd=TnUzMS81M2sxbDZIbERJU01tYkJCQT09__;!!P4SdNyxKAPE!Gg4oWbBxGQSSg8iwfieUq9U3j7MLZUDVF3-z6-GshsiVO1GzyT-yu_oHm98C03qrmvDK_S9hywyxdaOgEjjrXV0hnro$ ><br>
<br>
In case of problems, the zoom room is below:<br>
Meeting ID: 161 489 8082<br>
Passcode: 123456<br>
________________________<br>
<br>
<br>
<br>
_______________________________________________<br>
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