; ; creat uniform beam and store in FITS format ; radius in unit of pixel ; PRO create_uniform_beam, radius, beam array_size = fix(radius) *2 + 3 cent_pix = fix(radius)+1 beam = fltarr(array_size , array_size) FOR i=0,array_size-1 DO BEGIN FOR j=0,array_size-1 DO BEGIN dist = sqrt((i-cent_pix)^2. + (j-cent_pix)^2.) IF dist LT radius THEN BEGIN beam[i,j] = 1.0 ENDIF ENDFOR ENDFOR end