UV_DETECT Algorithm

          The UV_DETECT algorithm is basically that described by  Loomis  et  al
    2018    (2018AJ....155..182L,   see   https://arxiv.org/pdf/1803.04987.pdf).
    Here, instead of being implemented as a Python / CASA script, it is coded in
    Fortran and embedded into IMAGER. UV_DETECT  calls  an  imager  script  that
    reads the data set, computes a UV_MODEL from the ImageData using the UV cov-
    erage found in the UV data set, resamples this UV_MODEL at the same velocity
    resolution  than  the  UV data, and ultimately calls command UV_CORRELATE to
    apply the UV plane filter.

      As described in the original paper, the  UV  data  set  and  source  model
    available  in  ImageModel  must have the same centering. The ImageModel must
    also cover a sufficient width around its specified source velocity.

      The command will complain if the smoothing kernel described by the  Image-
    Model is insufficient.