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We aim to refine the sample of isolated early‐type galaxies in the Analysis of the interstellar Medium of Isolated Galaxies (AMIGA) catalog via high‐resolution imaging. Here, we report the result from a pilot study investigating two candidates, KIG 685 and KIG 895, in K‐band with the laser guide star and wavefront sensing facility ARGOS using the Large Binocular Telescope (LBT). Observations, obtained during the commissioning time, achieved a point spread function (PSF) of ≈0.25″. We present the data reduction and the PSF analysis from the best closed‐loop exposures to investigate the galaxies' morphological structure, including their nuclear region. We used PROFILER for the decomposition of the azimuthal 1D light distribution and GALFIT for the 2D analysis, accounting for ARGOS's PSF. KIG 685 was found to be a S0 galaxy and has been modeled with two Sérsic components representing a pseudobulge (n1D = 2.87 ± 0.21, n2D = 2.29 ± 0.10) and a disk (n1D = 0.95 ± 0.16, n2D = 0.78 ± 0.10). Nearly symmetric ring‐/shell‐like structures emerge after subtracting the GALFIT model from the image. KIG 895 shows a clear irregular arm‐like structure, in which the northern outer arm is reminiscent of a tail. The galaxy body is a disk, best fitted by a single Sérsic profile (n1D = 1.22 ± 0.1; n2D = 1.32 ± 0.12), that is, KIG 895 is a bulge‐less, very late‐type spiral. ARGOS high‐resolution images clearly showed interaction signatures in KIG 895. We suggest that the ring‐/shell‐like residuals in KIG 685, a bona fide early‐type galaxy, point toward a past accretion event. [ABSTRACT FROM AUTHOR]

We analyse high spatial resolution near infrared (NIR) imaging of NGC 6384, a Milky Way like galaxy, using ARGOS commissioning data at the Large Binocular Telescope (LBT). ARGOS provides a stable PSFFWHM = 0 |${^{\prime\prime}_{.}}$| 2–0 |${^{\prime\prime}_{.}}$| 3 AO correction of the ground layer across the LUCI 2 NIR camera 4 × 4 arcmin field by using six laser guide stars (three per telescope) and a natural guide star for tip-tilt sensing and guiding. Enabled by this high spatial resolution, we analyse the structure of the nuclear star cluster (NSC) and the central kiloparsec of NGC 6384. We find via 2D modelling that the NSC (r eff ≃ 10 pc) is surrounded by a small (r eff ≃ 100 pc) and a larger Sersić (r eff ≃ 400 pc), all embedded within the NGC 6384 large-scale boxy/X-shaped bulge and disc. This proof-of-concept study shows that with the high spatial resolution achieved by ground-layer AO we can push such analysis to distances previously only accessible from space. SED-fitting to the NIR and optical HST photometry allowed to leverage the age–metallicity–extinction degeneracies and derive the effective NSC properties of an young to old population mass ratio of |$8{{\ \rm per\ cent}}$| with |${\cal M}_{\rm \star ,old} \simeq 3.5\times 10^7\, \mathrm{M}_\odot$|⁠, Ageold, young = 10.9 ± 1.3 Gyr and 226 Myr |$\pm 62{{\ \rm per\ cent}}$|⁠, metallicity [ M / H ] = −0.11 ± 0.16, and |$0.33\pm 39{{\ \rm per\ cent}}$|  dex, and E (B − V) = 0.63 and 1.44 mag. [ABSTRACT FROM AUTHOR]