Molecular dynamics simulations of collisional cooling of highly charged ions in a penning trap

Molecular dynamics simulations of the cooling of highly-charged ions captured into a Penning ion trap (RETRAP) along with Be+ ions are described. Experimentally, the Be+ ions were directly cooled continuously using a laser, and collisional coupling to these laser-cooled ions cooled the highly-charged ions. The simulation is described as a tool for experimental interpretation and refinement. Under conditions closely related to the experimental parameters, the highly charged ions were found to form ordered structures, and to exhibit characteristics of a magnetized non-neutral plasma. (orig.)