## CLEAN

Progress is being made on automatic guess for Cleaning parameters, and a renaming of the parameter names is proposed. The table below is the proposed renaming scheme, with previous names mentionned in parentheses. It is proposed that the equivalent Old names (mentionned in Upper case below) will remain as aliases, while those mentionned in mixed case will disappear as they were seldom used before.

    		 CLEAN_ARES 		  Absolute residual  (ARES)

    CLEAN_FRES 		  Fractional residual (FRES)

    CLEAN_NITER 		  Maximum number of iterations (NITER)

    CLEAN_KEEP 		  Number of iterations used to check convergence (see below)

    CLEAN_METHOD 		  Cleaning Method  (METHOD)

    CLEAN_GAIN 		  Loop gain  (GAIN)

    CLEAN_MAJOR 		  Maximum number of Major cycles (Nmajor)

    CLEAN_SEARCH 		  Minimum primary beam threshold for searching (Search_W)

    CLEAN_RESTORE 		  Minimum primary beam threshold for restoring  (Restore_W)

    CLEAN_SPEEDY 		 Speeding factor for Clark (Spexp)

    CLEAN_WORRY 		 "Worry" factor for Clark (Worry)

    CLEAN_SMOOTH 		 Smoothing factor for Multi Scale Clean (Smooth)

    CLEAN_RATIO 		 Ratio for  Dual Resolution clean (Ratio)

    CLEAN_NGOAL 		 A number of components for ALMA joint deconvolution only (Ngoal)

Clean convergence is controlled by the usual ARES, FRES and NITER criteria, plus CLEAN_MAJOR for methods with major cycles. However, these criteria can be set to 0, allowing Mapping to automatically guess when to stop. In this case, convergence is controlled by CLEAN_KEEP, which is a number of components. Deconvolution of a given channel stops if the cumulative flux at iteration number N is smaller (resp. larger) than at iteration N-CLEAN_KEEP for positive signals (resp. negative). In essence, CLEAN_KEEP is the number of components when only noise is present. Experimentation with various types of images have shown that CLEAN_KEEP = 70 is a good compromise.