Electrostatic potential map in a Penning-Malmberg trap using numerical simulations

In order to produce antihydrogen, antiprotons and positrons must be mixed in a Penning-Malmberg trap. Before mixing, antiproton and positron plasmas are first confined at cryogenic temperatures. The positrons, for instance, originate in a trap consisting of a stack of eight hollow cylindrical electrodes. A potential is produced by applying a voltage to each electrode. Detailed modeling of the potential in each trap is crucial for tailoring the plasmas. We have found the potential well by solving the Laplace equation. We begin by developing a mechanical model of the trap in a computer-aided design (CAD) program, then inserting the model into a multiphysics modeling software, retrieving and converting the solution to the suitable form for the program that controls the experiment.