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The `CLEAN' algorithm


The `CLEAN' algorithm, introduced by Högbom (1974), assumes that the radio sky can be represented by a small number of point sources in an otherwise empty field of view. It uses a simple iterative procedure to find the positions and strengths of these sources. The final deconvolved `CLEAN' image is the sum of:

  1. these point-source `CLEAN components' reconvolved (``restored'') with a `CLEAN beam' (usually Gaussian) to de-emphasize the higher spatial frequencies which are often spuriously extrapolated and,
  2. (optionally, but strongly recommended) an image representing residual differences between the point-source model and the data.

We now describe some variants of the `CLEAN' algorithm, including two that can be used on large images.

1996 November 4
10:52:31 EST