The legacy of Don Madison – electron ionizing collisions with molecules

Don Madison was a pioneer in applying distorted-wave methods to a wide range of atomic and molecular collisions. He made significant contributions to theoretical methods of computing atomic excitation, electron-impact ionization of atoms and molecules, and ion-impact ionization. His work was notable through his long-standing close collaborations with experimental groups, and the flexibility that he demonstrated in applying his methods to a diverse range of targets. In this talk I focus on Don’s work that significantly advanced the field of electron-impact ionization of molecules, and in particular through the prediction of the angular distributions of the outgoing electrons from ionizing collisions. I will review the comparison of Don’s distorted-wave methods with experiment and with other theoretical methods for small and intermediate-size molecules. I’ll also show how such angular distributions are proving important in magnetic fusion plasma simulations. If time allows, I will also discuss Don’s work on heavy-particle collisions with atomic and molecular targets.