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RE: [Opal] 3D Field Maps in OPAL-T

Chronological Thread 
  • From: "Power, John" <JP AT>
  • To: Christof Metzger-Kraus <christof.j.kraus AT>, Nicole Neveu <nneveu AT>
  • Cc: opal <opal AT>
  • Subject: RE: [Opal] 3D Field Maps in OPAL-T
  • Date: Sun, 19 Mar 2017 15:44:50 +0000
  • Accept-language: en-US

Hi Christof,


That's great that you found the bug, embarrassing or not!  Do you have an idea when the next release will be out?





From: opal-request AT [opal-request AT] on behalf of Christof Metzger-Kraus [christof.j.kraus AT]
Sent: Sunday, March 19, 2017 10:11 AM
To: Nicole Neveu
Cc: opal
Subject: Re: [Opal] 3D Field Maps in OPAL-T

Hi Nicole,

the problem wasn't in the auto-phasing algorithm but in the evaluation of the 3D field map. This bug is quite embarrassing but fixed. Unfortunately you'll have to wait for the next release. Since setting the phase manually and using APVETO won't help, only a new binary.


On Fri, Mar 10, 2017 at 5:15 PM, Nicole Neveu <nneveu AT> wrote:
Hi Christof, 

Thanks for the email, I will try APVETO. 
Here is a link with the input files and field maps:
The T7 files are 2D and the txt are 3D. 



On Fri, Mar 10, 2017 at 1:52 AM, Christof Metzger-Kraus <christof.j.kraus AT> wrote:
Hi Nicole,

could you send me the input file. I'll look into it as soon as possible. In the meantime you could try to set the phase by hand using the phase that OPAL finds for the 2D fieldmap. When setting the phase manualy then you should add add APVETO=TRUE to the description of the cavity in the input file. Then OPAL doesn't try to auto-phase the cavity.


On Fri, Mar 10, 2017 at 4:54 AM, Nicole Neveu <nneveu AT> wrote:
Hi OPAL'ers, 

I recently tried to add a second 3DDynamic RF fieldmap to one of my beam line simulations in OPAL-T. I was seeing no energy gain in the second cavity with this beamline layout: 
3D RF gun ----Solenoids --- 3D RF Linac

After trying this and that, phase scan, etc, I paired the 3D Linac with a 2D gun, and saw energy gain: 
2D RF gun ----Solenoids--- 3D RF Linac

Inline image 1

Has anyone else seen this behavior? Do both cavities need to be exactly the same phase for OPAL to autophase or sync them? In this case, the desired freq is 1.3 GHz, and the two field maps differ by ~0.2 MHz. My guess is that is too small to make a difference?

I can send input files and data, if interested.



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