NGC 4636 (UGC 7878, 1240+0257)

NGC 4636 (UGC 7878, 1240+0257) -- This E/S0 galaxy has an optical LINER spectrum, with broad H wings (Ho et al. 1996a). The UV image shows diffuse, centrally-concentrated emission. This galaxy has also been imaged with HST by Lauer et al. (1995) in the V band, where it shows similar structure. The V-band brightness profile increases with decreasing radius down to the HST resolution, though with a shallower slope than most of the other early-type galaxies studied by Lauer et al. (1995). They estimate (after deconvolution with the spherically-aberrated PSF) a surface brightness of 16.5 mag arcsec-2 in the central $0.022", and 16.7 mag arcsec-2 at the $0.1" radius. The comparable UV brightnesses of this galaxy and NGC 1023 (which was also imaged by Lauer et al. 1995), despite the much higher optical surface brightness of NGC 1023, confirms that the red leak through the F220W filter contributes negligibly to the counts in the FOC exposures, and that most of the signal detected in the FOC exposures is, in fact, the result of UV flux (see Section 2.2 of the paper and notes on NGC 1023).