pro lmbdrk_sbsp,scnpos,srad,xctr,yctr,lmdrk ; routine to compute the theoretical limb darkening function for ; prescribed slit scan positions, solar radius, and center of the ; sp scan map ; INPUTS: scnpos = linear array of the scan center positions ; srad = solar radius at time of observation, arcsec ; xctr = x coordinate of map center, arcsec ; yctr = y coordinate of map center, arcsec ; OUTPUTS: lmdrk = 2-D array of intensity of limb darkening ; relative to disk center for prescribed slit ; scan positions ; This assumes these are normal maps ; Limb darkening function from Neckel and Labs, SP, 153, p.97, 1994 ; limb darkening polynomial coefficients vs mu ; values of aa are for wavelength 640.97 nm aa = [0.33644, 1.30590, -1.79238, 2.45040, -1.89979, 0.59943] nnx = n_elements(scnpos) ; generate arrays of map coordinates in arcseconds ; use the nominal values for step size ;xxpos = -1023. + findgen(2047) xxpos = scnpos*0.1476 yypos = -511. + findgen(1024) yypos = yypos*.1585 ypos = replicate(1.,nnx)#yypos + yctr xpos = xxpos#replicate(1.,1024) + xctr xpos = double(xpos) ypos = double(ypos) npoly = n_elements(aa) ;srad = 970. ; try sample solar radius in arcsec ; find arcsec radius to each point in map radd = sqrt(xpos*xpos + ypos*ypos) radf = radd/srad mu = sqrt(1.-radf*radf) lmdrk = mu lmdrk(*,*) = 0.D for kk=0,npoly-1 do lmdrk = lmdrk+aa(kk)*mu^kk ;tvwinp,lmdrk ;stop end