[ibsimu-forum] Initial beam&plasma questions

[申圳 <she...@im...>]

Dear all,




I'm using IBSimu (version 1.0.6) to simulate the extraction of multi-charged Ar beams from a 28GHz ECR ion source.

I'm using 3D cylindrical model with ParticleDataBase3D.add_cylindrical_beam_with_energy function to set initial beam conditions.

I've got some simulated beam profiles to compare with the experiment results of a flourescent at the extraction region.

Now I want to change the initial beam distributions of different ions, and I have some questions I can't deal with:

  1. I know from the Reference Manual that we can add beam with uniform, gaussian, waterbag,etc. distributions, but is there a chance to introduce distributions from other programs?

  2. If 1. is too complicated to do, then how can I add a hollow beam (for low charge state ions)?

  3. In space charge averaging:   if( i == 0 ) {
                                      scharge_ave = scharge;
                                  } else {
                                       double coef = 0.3;
                                       scharge *= coef;
                                       scharge_ave += scharge;
                                       scharge_ave *= (1.0/(1.0+coef));
                                  }

     what does this "coef" means?




Thanks a lot!

Zhen.