Modelling Summary

The previous section has shown that it is possible to use the ASTRA program to find a physical description of a cloud that reproduces observed data. This has been done for a cloud that has proved difficult to model realistically using traditional spherically symmetric programs. The modelling has confirmed the result from several other authors that the traditional Shu isothermal sphere distribution of $r^{-2}$ is almost certainly incorrect, at least for pre-stellar cold cores. The modelling has also revealed an unexpected velocity field of increasing infall velocity with radius rather than the inside out collapse predicted by Shu.