Dr Tom Kirchner: Shedding light on few-body quantum dynamics by studying atomic collisions

You are invited to attend PSYU's first event of the year - Dr Tom Kirchner's talk titled "Shedding light on few-body quantum dynamics by studying atomic collisions". Dr Kirchner teaches many courses at York, and as of this month has also become the department's Graduate Program Director. As per his page, "[his] research is concerned with the question of how atomic and molecular few-body systems respond to perturbations exerted on them by impinging particles and external fields". On January 12th, Dr Kirchner will speak about his own research and answer any question you might have on this exciting topic. Dr Kirchner's abstract: --- The quantum-mechanical few-body problem has challenged physicists ever since the foundations of quantum theory were laid in the 1920s. Collisions of atoms, molecules, and their ions are particularly interesting realizations of this problem, because the interaction potentials are well known and the question of how to deal with the few-body character of the collision system under study is the only fundamental difficulty for theory. Given the abundance of available experimental data and the importance of understanding them not just for fundamental but also for applied reasons, there is considerable motivation to address this difficulty. In my talk, I will outline a time-dependent quantum-mechanical approach based on the concepts of density functional theory, which we have developed over the years to describe nonrelativistic heavy-particle collisions from atoms and molecules. Recent results for helium and lithium atom as well as for water and methane molecule targets will be presented. Depending on the process under study the few-body problem presents itself as a more or less intricate one. I will discuss situations which reflect single-active-electron dynamics, independent-electron dynamics and more complicated, i.e., correlated, electron dynamics.