The OPAL Discussion Forum

[Christof Metzger-Kraus <christof.j.kraus AT gmail.com>]

Hi Daniel,

the bug was in the class FM3DDynamic, afaik the cyclotron-tracker doesn't use it.

christof

On Sun, Mar 19, 2017 at 4:51 PM, Daniel Winklehner <winklehn AT mit.edu> wrote:

Hi Christof,

Does this affect the 3D RF field maps in OPAL-cycl as well?

Thanks,

   Daniel

 

From: opal-request AT lists.psi.ch [mailto:opal-request AT lists.psi.ch] On Behalf Of Christof Metzger-Kraus
Sent: Sunday, March 19, 2017 11:12
To: Nicole Neveu <nneveu AT hawk.iit.edu>
Cc: opal <opal AT lists.psi.ch>
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.

Christof

 

On Fri, Mar 10, 2017 at 5:15 PM, Nicole Neveu <nneveu AT hawk.iit.edu> wrote:

Hi Christof, 

 

Thanks for the email, I will try APVETO. 

Here is a link with the input files and field maps:

https://drive.google.com/drive/folders/0B7NgZu2dVGNIdHJDNnJ0OTdGWmc?usp=sharing

The T7 files are 2D and the txt are 3D. 

 

Thanks! 

 

Nicole

 

 

 

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

christof

 

On Fri, Mar 10, 2017 at 4:54 AM, Nicole Neveu <nneveu AT hawk.iit.edu> 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

 

 

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.

 

Thanks, 

 

Nicole