The OPAL Discussion Forum

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

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