Radial star formation histories in 15 nearby galaxies

Journal Article · Fri Jan 01 04:00:00 EST 2016 · The Astronomical Journal (Online)

DOI:https://doi.org/10.3847/0004-6256/151/1/4· OSTI ID:22890169

Dale, Daniel A.; Hatlestad, Alan J.; Roberts, Jareth S.; Cook, David O.; Kobulnicky, Henry A.; Staudaher, Shawn M. ^[1]; Beltz-Mohrmann, Gillian D. ^[2]; Egan, Arika A. ^[3]; Herzog, Laura J. ^[4]; Leung, Andrew S.; McLane, Jacob N. ^[5]; Phenicie, Christopher ^[6]; Barnes, Kate L.; Zee, Liese van ^[7]; Boquien, Médéric ^[8]; Calzetti, Daniela ^[9]

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1. Department of Physics and Astronomy, University of Wyoming, Laramie WY (United States)
2. Department of Physics, Wellesley College, Wellesley MA (United States)
3. Department of Physics, Northern Michigan University, Marquette MI (United States)
4. Department of Physics and Astronomy, Minnesota State University, Moorhead MN (United States)
5. Department of Astronomy, University of Texas, Austin TX (United States)
6. School of Physics and Astronomy, University of Minnesota, Minneapolis MN (United States)
7. Department of Astronomy, Indiana University, Bloomington IN (United States)
8. Unidad de Astronomía, Universidad de Antofagasta, Antofagasta (Chile)
9. Department of Astronomy, University of Massachusetts, Amherst MA (United States)

New deep optical and near-infrared imaging is combined with archival ultraviolet and infrared data for 15 nearby galaxies mapped in the Spitzer Extended Disk Galaxy Exploration Science survey. These images are particularly deep and thus excellent for studying the low surface brightness outskirts of these disk-dominated galaxies with stellar masses ranging between 10{sup 8} and 10{sup 11} M{sub ⊙}. The spectral energy distributions derived from this data set are modeled to investigate the radial variations in the galaxy colors and star formation histories. Taken as a whole, the sample shows bluer and younger stars for larger radii until reversing near the optical radius, whereafter the trend is for redder and older stars for larger galacto-centric distances. These results are consistent with an inside-out disk formation scenario coupled with an old stellar outer disk population formed through radial migration and/or the cumulative history of minor mergers and accretions of satellite dwarf galaxies. However, these trends are quite modest and the variation from galaxy to galaxy is substantial. Additional data for a larger sample of galaxies are needed to confirm or dismiss these modest sample-wide trends.

• OSTI ID: 22890169
• Journal Information: The Astronomical Journal (Online), Journal Name: The Astronomical Journal (Online) Journal Issue: 1 Vol. 151; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BRIGHTNESS
DISTANCE
ENERGY SPECTRA
EXPLORATION
GALACTIC EVOLUTION
GALAXIES
MASS
PHOTOMETRY
SATELLITES
STAR EVOLUTION
STARS
SURFACES
ULTRAVIOLET RADIATION