Comparing Stellar Populations of Galaxies Across the Hubble Sequence
Abstract
From analysis of radial color gradients, it has been found that many late-type galaxies tend to become redder further out from the center of the galaxy (add references here). There are no feasible galaxy formation models that predict high metallicity in the outskirts of late-type galaxies, and these galaxies tend to show little evidence for significant amounts of dust at large radii. We therefore hypothesize the radial color gradients are primarily affected by stellar population ages. We observed irregular, elliptical, and spiral galaxies with the Infrared Sideport Imager (ISPI) on the 4-meter Blanco Telescope of Cerro Tololo Inter-American Observatory (CTIO) in Chile, using the J, H, and Ks near-infrared (NIR) filters. Elliptical aperture photometry was performed to obtain radial profiles of surface brightness, and of J-H and H-Ks colors. We analyze the relative contributions of stellar population ages, dust extinction and stellar metallicity to the radial color gradients. Detailed information like that gathered from this research, when expanded to statistical samples of nearby galaxies spanning a range of types, masses, and luminosities, is useful for comparison to studies of high-redshift galaxies and can serve as an observational benchmark that galaxy formation and evolution models must be able to reproduce.
- Publication:
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American Astronomical Society Meeting Abstracts #229
- Pub Date:
- January 2017
- Bibcode:
- 2017AAS...22915401E