Antoine Cerfon, CIMS
Vortex Dynamics in Cyclotrons
Abstract: Cyclotrons are compact particle accelerators that are used
on a regular basis for fundamental research in nuclear physics, for
cancer treatment, and for radioisotope production. New applications
have recently emerged that require cyclotrons to accelerate very
intense beams of charged particles. At these high intensities,
electrostatic interactions between the particles have a significant
effect on the beam dynamics, and the beam behaves like a plasma.
This new regime is poorly understood, and direct numerical
simulations are computationally costly.
In this talk, we start from the Vlasov equation for the charged
particles and use an asymptotic analysis to derive simple fluid
equations describing beam dynamics in cyclotrons. Remarkably, these
equations are formally identical to the two-dimensional Euler
equations for a fluid of uniform density. This analogy explains
several results observed in Particle-In-Cell simulations and
experiments. It also allows us to make new conjectures regarding the
stability of beams.