Face-on galaxies NGC 524 and NGC 6340: chemically decoupled nuclei and inclined circumnuclear disks

Abstract

Central regions of the early-type disk galaxies NGC 524 and NGC 6340 have been investigated with the Multi-Pupil Field Spectrograph at the 6m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences. I confirm the existence of chemically distinct stellar nuclei in these galaxies which have been claimed earlier. The metallicity differences which are found between the nuclei and the bulges, 0.5 - 1.0 kpc from the centers, reach 0.5 - 0.6 dex. Both nuclei are magnesium overabundant, but the bulges have different magnesium-to-iron ratios: it is solar in NGC 6340 and the same as the nuclear one in NGC 524. The kinematical and morphological analyses reveal the existence of inclined central disks in these galaxies. In NGC 524 the central disk consists of stars, dust, and ionized gas; its extension may be as large as up to R=3 kpc, and it is inclined by more than 20 deg to the global galactic plane. In NGC 6340 only a gaseous polar disk with the radius less than 500 pc is detected.

25 pages, 15 figures, to appear in Astronomical Journal, August2000 issue

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Cited by in corpus (15)

• The SAURON project - V. Integral-field emission-line kinematics of 48 elliptical and lenticular galaxies
• The SAURON project - III. Integral-field absorption-line kinematics of 48 elliptical and lenticular galaxies
• Molecular gas and star formation in early-type galaxies
• Gemini/GMOS Imaging of Globular Cluster Systems in Five Early-type Galaxies
• Minor-axis velocity gradients in spirals and the case of inner polar disks
• Ages and abundances in large-scale stellar disks of nearby S0 galaxies
• Stellar Populations in Nearby Lenticular Galaxies
• WISDOM project - IV. A molecular gas dynamical measurement of the supermassive black hole mass in NGC 524
• NGC 6340: an old S0 galaxy with a young polar disc. Clues from morphology, internal kinematics and stellar populations
• Keck Spectroscopy and Imaging of Globular Clusters in the Lenticular Galaxy NGC 524
• Inner Polar Rings and Disks: Observed Properties
• Splitting the lentils: Clues to galaxy/black hole coevolution from the discovery of offset relations for non-dusty versus dusty (wet-merger-built) lenticular galaxies in the $M_{\mathrm{bh}}$-$M_{\ast ,\mathrm{spheroid}}$ diagram
• Lenticular galaxies with UV-rings
• Star Formation History at the Centers of Lenticular Galaxies with Bars and Purely Exponential Outer Disks from SAURON Data
• Synchronous Evolution of Galaxies in Groups: NGC 524 Group