Multi-photon and electron collisions

One of the major outstanding problems in atomic physics is the accurate calculation of collision data for low ionization stages of iron peak elements such as iron, cobalt and nickel. This data is urgently required in the analysis of observations by the Hubble Space Telescope of gaseous nebulae and in the analysis of laboratory spectra from, for example, laser-plasma interactions and tokamaks.

It is now possible to include considerably more sophisticated wave functions to describe both the target and the collisional states than was previously possible. First calculations are showing detailed CI effects in electron collisions with atoms or atomic ions with an open 3d shell. This has revealed the need for extensive calculations to allow for correlation effects both in the target and in the collision system