apply the [pedsub]{} task to the calibrated image, quadrant by quadrant, determine the shifts of the dithered images with [xregister]{}, register them with [imshift]{}, and finally combine them with [imcombine]{}.

UM 625 extends far beyond the $\sim11\arcsec\times11\arcsec$ field of view of NIC1. In spite of this, a GALFIT model consisting of a PSF + [Sérsic]{} bulge can still give a fairly robust measurement of the nuclear magnitude. During the fitting, we set the background free and masked the ring region as before. It proved to be impossible to independently measure the disk component at all. Since we know from the optical images that a disk [*is*]{} present, we constrain it by fixing its structural parameters to those derived from the F606W image and normalizing its luminosity such that $R-H=2$ mag, a value typical of disks (e.g., MacArthur et al. 2004). However, we note that none of the parameters for the bulge or the AGN point source are significantly affected by our assumptions for the disk component. The best-fit model

\[xray\]

yields $n=1.54$ and $r_e =$ 098 (491 pc) for the bulge. If we fix the bulge $n$ and $r_e$ to the values derived from the F606W fit, the AGN magnitude 