Elegant users forum

Using the subdivision feature in CWIGGLER is the same as other elements. You have two options

• Use the element_divisions parameter of the run_setup command.
• Use the divide_elements command.

--Michael

Seb, There's some infrastructure in elegant to support variable weighting of simulation particles. However, implementing it consistently across the code is a big job that I haven't found time to take on. For example, you'll note in track.h there is a definition of a quantity weightIndex. This gives ...

Sara,

Thanks for your post!

--Michael

I'm not sure what you mean, but perhaps you refer to the lattice parameter in the &run_setup command. That parameter names the file that defines the lattice (the layout of magnets and other components).

In that particular example, the file is called lattice.lte

--Michael

You can simulate the effect of impedance on the beam. To actually determine the impedance, you need to use another code, e.g., GDFIDL, CST, ECHO, ABCI, ...

--Michael

Looking at your files, I don't see any obvious problems. A few things to try: More particles, to see if it is something real or just statistics. Reduce the sigma span of the random number generator used for synchrotron radiation, e.g., &global_settings SR_gaussian_limit = 2 &end I suspect that there...

Sara,

Yes, I would agree with your conclusions. I'd suggest finer steps in charge at the low end to ensure you aren't underestimating the threshold, which seems quite low.

--Michael

Sara,

Unless the handles reappear, I wouldn't consider that MWI. It may just be the bunch settling into the rf bucket that is distorted by potential well distortion.

--Michael

Chao, The coupled trajectory correction requires that only HMON and VMON elements are present in the beamline, so I converted your lattice. The attached files work for trajectory correction, but the tune correction isn't stable. Is this a ring that is strongly coupled, or a transport line? The coupl...

Sara,

I'd suggest using more particles and finer spacing of the points in current. I'd hope that will give a clearer threshold.

--Michael