[FFA_CEBAF_Collab] [EXTERNAL] Re: Alternative FFA Arc - A tech note describing a brainstorm

Fri Dec 8 15:06:39 EST 2023

Hi Stephen,

As I think you pointed out in the FFA workshop at Cornell, not all path need to be regulated to on-crest acceleration. The phase of the addition of RF fields has to have the appropriate phase, not every path. I think this should help a lot. The orbits are only for fine-tuning and might not need to amount to a large phase difference.

Best,
Georg

========================================================
|
| Georg H Hoffstaetter de Torquat, Professor of Physics
| Cornell University and Brookhaven National Laboratory
| Director of ERL / EIC collaboration, Cornell PI CBETA
| Fellow of the German National Merit Foundation and APS
| 404 Physical Sciences Building, Tel. : +1 2012 52 7731
| Cornell University, Newman Laboratory, Ithaca/NY 14853
| email: gh77 at cornell.edu<mailto:gh77 at cornell.edu>, https://urldefense.proofpoint.com/v2/url?u=http-3A__georg.hoffstaetter.com&d=DwIGaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=Ogg4WFNBwvADBq3fkmCLiJ7SaRDPYtawHzJElJMB0jE&m=Xy7lox33pKEpBdR0s2qTLeZi_hAiNBO-hrXVAIJN6msK_sU50EGqhHeiZaTUY4_g&s=OOE6RU64Zwvk8gp_E0Lslb0Uj-1GkNoaATa3EZd7mcs&e= <https://urldefense.proofpoint.com/v2/url?u=http-3A__georg.hoffstaetter.com_&d=DwIGaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=Ogg4WFNBwvADBq3fkmCLiJ7SaRDPYtawHzJElJMB0jE&m=Xy7lox33pKEpBdR0s2qTLeZi_hAiNBO-hrXVAIJN6msK_sU50EGqhHeiZaTUY4_g&s=sZ9tHmYp2Lo-wQTkZAQYBVPLObZGjarsl434dwGhxtg&e= >
|
========================================================

On Dec 8, 2023, at 10:02 AM, Brooks, Stephen <sbrooks at bnl.gov<mailto:sbrooks at bnl.gov>> wrote:

I think the devil is in the details.  Closed orbit bumps will probably not provide *enough* path length adjustment, when restricted to using practical fields and apertures.  They also have to be closed for all energies simultaneously, which becomes more complex as the number of passes increases.

Also, having independent adjustment of the passes is probably good operationally.

    -Stephen

________________________________________
From: FFA_CEBAF_Collab <ffa_cebaf_collab-bounces at jlab.org<mailto:ffa_cebaf_collab-bounces at jlab.org>> on behalf of Georg Heinz Hoffstaetter de Torquat via FFA_CEBAF_Collab <ffa_cebaf_collab at jlab.org<mailto:ffa_cebaf_collab at jlab.org>>
Sent: 08 December 2023 08:59
To: Andrei Seryi
Cc: ffa_cebaf_collab at jlab.org<mailto:ffa_cebaf_collab at jlab.org>
Subject: [FFA_CEBAF_Collab] [EXTERNAL] Re:  Alternative FFA Arc - A tech note describing        a       brainstorm

Hi Andrei,

This is an excellent strategy and the ultimate application of FFAs for recirculating system. I would love to see this realized some day. Dejan and I, and others, have talked about this a lot and it has been considered. Alas, there are space constraints. Dejan, Scott, and Stephen, can probably tell more about the specific problems.

All the best,
Georg

On Dec 8, 2023, at 8:41 AM, Andrei Seryi via FFA_CEBAF_Collab <ffa_cebaf_collab at jlab.org<mailto:ffa_cebaf_collab at jlab.org><mailto:ffa_cebaf_collab at jlab.org>> wrote:

Colleagues,

I was talking to Thomas Roser last week at DESY about our design.
He suggested to avoid spreaders and combiners altogether, and instead use FFA-like beamline that adiabatically transition to regular FFA of the arcs. I.e., it will be FFA with varying cell length – starting from longer near linacs, to shorter cell in the arcs.
The timing corrections of individual energies can be done by some closed bumps.
Can this be considered?

Thanks
  Andrei

From: FFA_CEBAF_Collab <ffa_cebaf_collab-bounces at jlab.org<mailto:ffa_cebaf_collab-bounces at jlab.org><mailto:ffa_cebaf_collab-bounces at jlab.org>> On Behalf Of Ryan Bodenstein via FFA_CEBAF_Collab
Sent: Thursday, December 7, 2023 11:35 AM
To: ffa_cebaf_collab at jlab.org<mailto:ffa_cebaf_collab at jlab.org><mailto:ffa_cebaf_collab at jlab.org>
Subject: [FFA_CEBAF_Collab] Alternative FFA Arc - A tech note describing a brainstorm

Dear FFA Colleagues,

Since we’ve been entertaining a lot of alternative options lately, I thought I’d add to the pile.

I’ve spoken to a few of you about this, but I thought I’d write it down informally and share it with the group. Please note: this is no more than brainstorming put to paper (or digital paper, if you will). But it describes a few alternative ways to design the FFA arcs. These ideas may or may not be feasible, and may or may not help things. They will likely cost more, but may be worth it.

Attached, you’ll find a copy of the tech note. If you are on JLab’s network, you can also find it here:  https://urldefense.proofpoint.com/v2/url?u=https-3A__nam12.safelinks.protection.outlook.com_-3Furl-3Dhttps-253A-252F-252Fjlabdoc.jlab.org-252Fdocushare-252Fdsweb-252FView-252FCollection-2D55373-26data-3D05-257C02-257Cgeorg.hoffstaetter-2540cornell.edu-257Cab73201d8c394ab2f35c08dbf7feafa3-257C5d7e43661b9b45cf8e79b14b27df46e1-257C0-257C0-257C638376445464862624-257CUnknown-257CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0-253D-257C3000-257C-257C-257C-26sdata-3DOCTngL-252F8JuUqtds9jvgm-252FmwyEZ5tNyYyxpP0z8FcHiU-253D-26reserved-3D0&d=DwIGaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=Ogg4WFNBwvADBq3fkmCLiJ7SaRDPYtawHzJElJMB0jE&m=Xy7lox33pKEpBdR0s2qTLeZi_hAiNBO-hrXVAIJN6msK_sU50EGqhHeiZaTUY4_g&s=HSatPbZ0l8fWWhlNKrnUilggNEhoQOB4IOiafJ0g5Nc&e= <https://jlabdoc.jlab.org/docushare/dsweb/View/Collection-55373>

Cheers!
Ryan

Dr. Ryan Bodenstein (he/him)
Staff Scientist II – Center for Advanced Study of Accelerators (CASA)
<image002.jpg>
12000 Jefferson Avenue
Newport News, VA 23606
United States of America
_______________________________________________
FFA_CEBAF_Collab mailing list
FFA_CEBAF_Collab at jlab.org<mailto:FFA_CEBAF_Collab at jlab.org><mailto:FFA_CEBAF_Collab at jlab.org>
https://urldefense.proofpoint.com/v2/url?u=https-3A__nam12.safelinks.protection.outlook.com_-3Furl-3Dhttps-253A-252F-252Fmailman.jlab.org-252Fmailman-252Flistinfo-252Fffa-5Fcebaf-5Fcollab-26data-3D05-257C02-257Cgeorg.hoffstaetter-2540cornell.edu-257Cab73201d8c394ab2f35c08dbf7feafa3-257C5d7e43661b9b45cf8e79b14b27df46e1-257C0-257C0-257C638376445464862624-257CUnknown-257CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0-253D-257C3000-257C-257C-257C-26sdata-3D0czGzetiSti26HV8oAtu3e89eWUbUx8nRZVjmdg1xQ0-253D-26reserved-3D0&d=DwIGaQ&c=CJqEzB1piLOyyvZjb8YUQw&r=Ogg4WFNBwvADBq3fkmCLiJ7SaRDPYtawHzJElJMB0jE&m=Xy7lox33pKEpBdR0s2qTLeZi_hAiNBO-hrXVAIJN6msK_sU50EGqhHeiZaTUY4_g&s=n0vNr-unaEAMZyx35VjX56sJAsa5p1BBx5Y8i1Mzu-k&e= <https://mailman.jlab.org/mailman/listinfo/ffa_cebaf_collab>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mailman.jlab.org/pipermail/ffa_cebaf_collab/attachments/20231208/98442fe5/attachment-0001.html>