Old_Names:

      Some  of  the  CLEAN  parameters  have  kept their old names: BLC, TRC and
    BEAM_PATCH (which are seldom used)

      Others have equivalent short names: ARES, FRES, GAIN, NITER for which  the
    CLEAN_ prefix may be omitted.

      MAJOR,  MINOR, ANGLE (which were used to control the Clean beam size) have
    been replaced by BEAM_SIZE[3]