The OPAL Discussion Forum

["Power, John" <JP AT anl.gov>]

I would like to simulate an emittance measurement for an electron beam out of a RF photocathode gun.  I would like to simulate a scanning slit by running a number of cases with the 'slit' is different locations.  Can I use the element called 'Slit', mentioned in section 18.5, to do this by changing the parameters in APERTURE={0.005,0.003}? 

 

FX5: Slit, L=0.09, ELEMEDGE=0.01, APERTURE={0.005,0.003},SURFACEPHYSICS=’KX2IPHYS’;

 

For this emittance study, I only need the transmitted particles. I.e., I do not need to track the absorbed particles but I did not see a way to perfectly block them.  On the other hand, it is also ok if OPAL tracks the absorbed particles.

 

thanks,

John