  We apply the convergent close-coupling (CCC) formalism to analyse the
processes of laser assisted electron impact ionisation of He, and the
attosecond time delay in the photodetachment of the H^{-} ion and the
photoionisation of He. Such time dependent atomic collision processes are of
considerable interest as experimental measurements on the relevant timescale
(attoseconds 10^{-18} s) are now possible utilising ultrafast and intense laser
pulses. These processes in particular are furthermore of interest as they are
strongly influenced by many-electron correlations. In such cases their
theoretical description requires a more comprehensive treatment than that
offered by first order perturbation theory. We apply such a treatment through
the use of the CCC formalism which involves the complete numeric solution of
the integral Lippmann-Schwinger equations pertaining to a particular scattering
event. For laser assisted electron impact ionisation of He such a treatment is
of a considerably greater accuracy than the majority of previous theoretical
descriptions applied to this problem which treat the field-free scattering
event within the first Born approximation. For the photodetachment of H^{-} and
photoionisation of He, the CCC approach allows for accurate calculation of the
attosecond time delay and comparison with the companion processes of
photoelectron scattering on H and He^{+}, respectively.
