Blind processing in astrophysical data analysis

Some blind approaches to a typical problem in astrophysical data analysis are briefly recalled. The problem is to disentangle different radiation maps from a multichannel map where signals coming from different astrophysical sources are mixed. Some separation methods assume a perfect knowledge of the mixing operator. However, if the model does not explain the data, this approach can lead to very poor results. Conversely, a blind approach, that is, one that does not enforce a rigid data model, is able to match the data while preserving all the desirable properties of the result.