GitLab

- let unit test be run from anywhere,
- clean up

in svn+ssh://savannah02.psi.ch/repos/opal/tests/trunk/Collimator 

 - Now we have to check again aginst FLUKA and mabe mcmpx (ToDo: Y. Bi)

 - In the collimator physics class the start of the collimator in floor coordinates is wrong
    is always 0.0 (ToDo: A. Adelmann)

- In the collimator physics class there is a duplocation of the actual collimator code, this needs to be elliminated (A. Adelmann)

- One has to check the CCollimator (ToDo: J. Yang)

energy spectrum, but something with the beams x,z,y coordinates is
still wrong. I guess it is a units problem in CoulombScat.

Check the test in opal-tests/Collimator

commit Jeroen contribution on the collimator physics: (1) use a more precise formula for low energy, (2) set a bottom threshold (directly delete the particle if its energy is lower than this threshold)

Change the arguments of CCOLLIMATOR element to XSTART, XEND, YSTART, YEND, WIDTH so as to model non-radial oriented collimator

- use forward declaration where possible
- remove unused includes