CCC Homepage

This site contains some information regarding the convergent close-coupling (CCC) computer code, which supplements the information available at the ampgateway. An interested beginner may wish to start at the simple single-node version, available as, which is Chapter 8 of Computational Atomic Physics edited by Klaus Bartschat.

The CCC computer code solves (anti)electron or photon scattering on quasi one- or two-electron targets. The close-coupling equations are formed by expanding the total wave-function of the system in a truncated complete Laguerre basis, which are solved in momentum space as coupled linear equations. Convergence is obtained by simply increasing the basis size. It is written in Fortran using a hybrid MPI/OpenMP/GPU parallelism, and implemented for multi-node HPC systems. An example of scaling on computers at Australia's National Computing Infrastructure and the Pawsey Supercomputer Centre is below

Examples of input files for the following collision problems:

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