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MAP_CONTINUUM GAUSS

        [ADVANCED\]MAP_CONTINUUM  [DIRTY|CLEAN|Other] /METHOD GAUSS [Thresh-
    old [Nhist]]

      Compute the continuum based on the per-pixel spectrum.  Each  spectrum
    is sigma-clipped and the histogram of the intensity distribution is fit-
    ted by a Gaussian.  Corrective techniques are applied to ensure the  fit
    has converged.  The position of this Gaussian gives the continuum level.
    A noise estimate is also derived.

      The method does not deliver a spatially independent noise, but  adapts
    the  bandwidth  to  the  line free zones for each pixel. It may fail for
    pixels with are close to line confusion.

      The optional arguments control the algorithm.  Threshold  is  clipping
    level  value  for  the Gaussian: valuesi n range 2.5 - 4 are usable (de-
    fault 3.5).  Nhist is the number of histogram bins. The  default  is  to
    adjust this number depending on the number of channels in the data.


Gildas manager 2023-06-01