Talk on the symplectic methods in our seminar from MOX

MOXAbele Simona and Luca Bonaventura from MOX, Politecnico di Milano will talk on 13 Mar 2017, 16:15–17:45 in S2|17-103 about Numerical approximation of charged particle motion in magnetic quadrupoles.
We present some attempts at improving the accuracy and efficiency of the reference numerical methods presently employed to model charged particle motion in magnetic quadrupoles. We first introduce the standard technique used to reconstruct the quadrupole magnetic vector potential, based on general solutions of the Laplace equation in cylindric coordinates. We then compare various time integration methods, in order to assess how a reduction of the (large) computational cost involved could be achieved. In particular, we consider some of the methods used in the accelerator physics community, based on a Lie algebra approach, along with other symplectic methods and non symplectic ones. The results show that higher order methods could provide a more efficient alternative to the lower order approximations presently employed. This is joint work with the group of Dr. Barbara Dalena of CEA (Commissariat à l’énergie atomique et aux énergies alternatives), Saclay, France.