[Sbs] note by Jay Benesch on interaction of SBS magnet field and beam

[Mark Jones]

The recent DOE review had the comment:

"An issue noted from the last review, the possible effect of beam size 
on transport to the beam dump, has not been modeled.  An estimate 
should be made in conjunction with the JLAB beam experts."

Bogdan contacted Jay Benesch who did his own TOSCA calculation using
Bodgan's configuration file. He wrote a note on interaction of 
SBS magnet field and beam. It is at
https://cnidlamp.jlab.org/SBS-experiments/JDocDB/system/files/biblio/2015/12/beamline-field-jayb-model_discussion.pdf

For me, the main key sentences are:

"The Cos1 and Sin1 terms are comparable to those used around 200 MeV in the
first pass North Linac. One would see their effects in particle tracking only on such low energy
particles, which we have already shown will terminate on an aluminum plate in the dump alcove due to
the uncorrected Bx Cos0 (dipole) which causes vertical deflection."


           Cheers,
                  Mark