[Pansophy] C100 RF Incoming Inspection QextFPC

Mon Apr 11 08:52:04 EDT 2022

Good morning.

C100R-CAV-RFIN-R3 has been uploaded to the Ready for Approval folder and is ready to route for signatures.

https://jlabdoc.jlab.org/docushare/dsweb/View/Collection-49545

Tiffany Ganey

-----Original Message-----
From: Haipeng Wang <haipeng at jlab.org> 
Sent: Friday, April 8, 2022 2:00 PM
To: Tiffany Ganey <ganey at jlab.org>; Tony Reilly <areilly at jlab.org>; Kirk Davis <kdavis at jlab.org>; Danny Forehand <forehand at jlab.org>; Roland Overton <overtonr at jlab.org>
Subject: Re: C100 RF Incoming Inspection QextFPC

Thank you. Tiffany. That is correct.
Haipeng

On 4/8/2022 1:43 PM, Tiffany Ganey wrote:
>
> Haipeng - Thank you for the information.
>
> All - I've updated the C100R-CAV-RFIN traveler step 3 to include the 
> acceptance criteria for QextFPC (see screen shot below and 
> attachment).  If any changes or corrections are needed, please let me 
> know.  Otherwise I will submit the new revision for approval early 
> next week.
>
> Thank you,
>
> Tiffany Ganey
>
> -----Original Message-----
> From: Haipeng Wang <haipeng at jlab.org>
> Sent: Thursday, April 7, 2022 11:15 AM
> To: Tom Powers <powers at jlab.org>; Jay Benesch <benesch at jlab.org>; 
> Tiffany Ganey <ganey at jlab.org>; Robert Rimmer <rarimmer at jlab.org>; 
> Michael Drury <drury at jlab.org>; Curt Hovater <hovater at jlab.org>; 
> Charlie Reece <reece at jlab.org>
> Cc: Tony Reilly <areilly at jlab.org>; Kirk Davis <kdavis at jlab.org>; 
> Danny Forehand <forehand at jlab.org>; Roland Overton 
> <overtonr at jlab.org>; Roger Ruber <ruber at jlab.org>
> Subject: Re: C100 RF Incoming Inspection QextFPC
>
> Tiffany,
>
>     As I have communicated to you yesterday and based on the fact that 
> this C100R cryomodule  is being refurbished from its original location 
> at NL25. Its fabricated cavity geometry  by sheet metal can not be 
> modified anymore. I would like to set original specification as this 
> Frank's recent publication paper in 2021 indicated in Table 1 for the
>
> C100 7-cell (Low Loss cavity) as 3.2e7, but I am relaxing the lower 
> error boundary to -68% and keeping upper error boundary to +20%. That 
> will give the Q external value for the QA from 1.02E7 to 3.84E7 range.
>
> This change would easy the new Qext requirement and an accommodation 
> of stub tuning range for the CPP and High Power runs on all C100 
> cryomodules for the CEBAF operation in near future.
>
>     Please let me know if any paper work and a technical review need 
> to be done accordingly.
>
> Best Regards
>
> Haipeng Wang
>
> Senior Staff Scientist, SRF System Group Leader Thomas Jefferson Lab 
> Accelerator Operation and R&D Division
>
> 600 Kelvin Drive
>
> Suite 8, MS 55H, Bldg 58_2, Room 2232
>
> Newport News, VA 23606, USA
>
> Phone
>
> (O): 757-269-5435
>
> (C): 804-836-0539
>
> (F): 757-269-7658
>
> E-mail: haipeng at jlab.org <mailto:haipeng at jlab.org>
>
> On 4/6/2022 11:12 AM, Tom Powers wrote:
>
> > Attached is Jean's technote where they set the spec to 3e7.  I also
>
> > included is the references which were the basis for the numbers.  Of
>
> > course Jean used the most current microphonics data at the time 
> > which
>
> > was from SL21 and the F100 which have a different cell shape than 
> > the
>
> > production C100 cavities.
>
> >
>
> > In fact from a microphonics standpoint, SL21 is the quietest
>
> > cryomodule in the machine and the F100 is second.
>
> >
>
> > So they changed the cavity shape then took out the stiffening rings,
>
> > (??assumed that the microphonics would remain constant??) and never
>
> > revisited the loaded-Q.
>
> >
>
> > *Thus the cavity which was basis for setting C100 loaded-Q to 3e7 
> > was
>
> > the WRONG CAVITY.*
>
> >
>
> > T
>
> >
>
> > On 4/6/2022 10:37 AM, Jay Benesch wrote:
>
> >> Haipeng,
>
> >>
>
> >> JLAB-TN-05-009 Charlie Reece
>
> >> SRF Cavity Cell Geometry Options for the CEBAF 12 GeV Upgrade is 
> >> the
>
> >> closest thing I could find to a C100 spec in the TN repository.
>
> >> https://jlabdoc.jlab.org/docushare/dsweb/View/Collection-12484
> <https://jlabdoc.jlab.org/docushare/dsweb/View/Collection-12484>
>
> >>
>
> >> Looking at the plots Tom has generated for me recently, I propose
>
> >> bandwidth 115+-5 Hz for all cavities; QL 12.5E6 to 13.6E6
>
> >> C25/C50/C75/C100 would all eventually be equipped with stub tuners
>
> >> and so adjusted.  I recognize that the sheet metal tolerance is
>
> >> +-30%. It will be a lot easier for the RF techs if there is just 
> >> +one
>
> >> number for all cavity types.
>
> >>
>
> >> See my J-Future talk for two of Tom's plots and the present CED
>
> >> distribution of QLs.
>
> >> 
> https://indico.jlab.org/event/520/contributions/9437/attachments/7695
> <https://indico.jlab.org/event/520/contributions/9437/attachments/7695
> >
>
> >> /10741/J_Future_J_Benesch.pdf
>
> >>
>
> >> Other talks at the meeting may be of interest.
>
> >> https://indico.jlab.org/event/520/timetable/#all.detailed
> <https://indico.jlab.org/event/520/timetable/#all.detailed>
>
> >>
>
> >> Jay
>
> >>
>
> >> On 4/6/22 10:19, Haipeng Wang wrote:
>
> >>> Tiffany,
>
> >>>      I can take Frank's role to fill this spec. However in a 
> >>> recent
>
> >>> activity by EES to use 3-stub tuners at service buildings of 
> >>> CEBAF,
>
> >>> we have to lower the Qext to ~1e7 than 2~3e7 on the C100
>
> >>> cryomodules. For this refurbished C100R cryomodule, we might have 
> >>> to
>
> >>> lower the Qext as we are going to run higher beam current for CPP
>
> >>> and High Power CEBAF programs in coming years. I would like to ask
>
> >>> higher managers to start a meeting with stake holders of Jay, Tom,
>
> >>> Curt, Charlie and me to discuss about this. It should be straight
>
> >>> forward decision process for the new spec. However, the cavity end
>
> >>> cell iris to the FPC center-line dimension is fixed in the old 
> >>> C100
>
> >>> module, I don't think it is easier to change the design and modify
>
> >>> on it. So I might have to find the original C100 spec to fill in 
> >>> the
>
> >>> Qext spec. Charlie or Mike might be able to find where does this
>
> >>> C100R module come from, what is the original Qext spec?
>
> >>> Regards
>
> >>> Haipeng
>
> >>>
>
> >>> On 4/6/2022 9:49 AM, Tiffany Ganey wrote:
>
> >>>>
>
> >>>> For the C100R project, the C100R-CAV-RFIN traveler needs to be
>
> >>>> updated to provide a specific range of acceptable QextFPC 
> >>>> measured
>
> >>>> during a cavity’s incoming inspection.  The current traveler has 
> >>>> a
>
> >>>> data field to capture the measured QextFPC but no specification 
> >>>> is
>
> >>>> provided. It’s my understanding that previously Frank looked at 
> >>>> the
>
> >>>> travelers and approved the data as he knew the required range for
>
> >>>> this value.
>
> >>>>
>
> >>>> Can you please provide the QextFPC specification range for a C100
>
> >>>> cavity so that the traveler can be revised to provide this
>
> >>>> information going forward?
>
> >>>>
>
> >>>> Thank you,
>
> >>>>
>
> >>>> Tiffany Ganey
>
> >>>>
>
> >>>
>
> >>
>
> >>
>
> >>
>
> >
>