Anisotropic scattering for neutralization of a proton beam through a charge exchange cell

[kyfranzen]

Hello PICLAS team,
I am interested in using PICLAS to simulate neutralization of a 60 keV proton beam passing through a charge exchange cell. I have tried to set up a simplified model with the chemistry reactions largely following the example in the regressioncheck/NIG_PIC_poisson_Boris-Leapfrog/3D_HET_Liu2010 folder with the cross sections extended up to the relevant energy levels . One problem I am seeing is that neutralized hydrogen atoms are isotropically scattered which is not what happens in a real system in which just a few milliradians are added to the outgoing beam divergence. Is there a way in PICLAS to implement anisotropic scattering for high energy particle reactions to better line up with measurements?

By the way, I already tried to adjust the VSSalpha value as described in section 4.9.2. Pairing & Collision Modelling, but it does not seem to help. So far I only tried to add and adjust Part-Species$-alphaVSS values to the DSMC.ini file, since I could not get the collision-specific VSSalpha definition method as described in 4.9.2 to work at all. Perhaps there is a regressioncheck example of this or similar setup?

Thanks!,
Ken