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Stellar Populations and Kinematics in Spiral Galaxies

Published online by Cambridge University Press:  13 April 2010

Lauren A. MacArthur ,
J. Jesús González ,
Stéphane Courteau  and
Michael McDonald
Lauren A. MacArthur
Affiliation:
Herzberg Institute of Astrophysics, National Research Council of Canada/University of Victoria, Victoria, BC, Canada; email: Lauren.MacArthur@nrc-cnrc.gc.ca
J. Jesús González
Affiliation:
Universidad Nacional Autónoma de México, México
Stéphane Courteau
Affiliation:
Queen's University, Kingston, ON, Canada
Michael McDonald
Affiliation:
University of Maryland, College Park, MD, USA
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Abstract

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We present a detailed study of the stellar populations (SPs) and kinematics of the bulge and inner disk regions of nearby spiral galaxies (Sa-Sd) based on deep long-slit Gemini/GMOS data. We find that the SPs of spiral galaxies are not well matched by single episodes of star formation; representative SPs must involve average SP values integrated over the star formation history (SFH) of the galaxy, such as those derived from the “full population synthesis” method used here. Our spiral bulges follow the same correlations of increasing light-weighted age and metallicity with central velocity dispersion as those of elliptical galaxies and early-type bulges found in other studies, but when SFHs more complex and realistic than a single burst are invoked, the trend with age is shallower and its scatter much reduced. In a mass-weighted context, all bulges are predominantly composed of old and metal-rich SPs. Bulge formation appears to be dominated by early processes that are common to all spheroids, whether they currently reside in disks or not. While monolithic collapse cannot be ruled out in some cases, merging must be invoked to explain the SP gradients in most bulges. Further bulge growth via secular processes, or “rejuvenated” star formation, generally contributes minimally to the stellar mass budget. We also demonstrate how the combination of our full population synthesis modeling of high-quality optical spectra of integrated SPs along with optical-NIR broad-band imaging can single out potential model weaknesses and help determine the reliability of the inferred SFHs.

Keywords

galaxies: spiralgalaxies: stellar contentgalaxies: formation
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 5 , Symposium S262: Stellar Populations – Planning for the Next Decade , August 2009 , pp. 172 - 175
Copyright
Copyright © International Astronomical Union 2010

References

Bruzual, A. G. & Charlot, S. 2003, MNRAS, 344, 1000 [BC03]CrossRefGoogle Scholar
Chabrier, G. 2003, PASP, 115, 763CrossRefGoogle Scholar
Charlot, S. & Fall, S. M. 2000, ApJ, 539, 718CrossRefGoogle Scholar
Cid Fernandes, R. et al. 2005, MNRAS, 358, 363CrossRefGoogle Scholar
Coelho, P. et al. 2007, MNRAS, 382, 498CrossRefGoogle Scholar
Ganda, K. et al. 2007, MNRAS, 380, 506CrossRefGoogle Scholar
Heavens, A. F., Jimenez, R., & Lahav, O. 2000, MNRAS, 317, 965CrossRefGoogle Scholar
MacArthur, L. A., Courteau, S., Bell, E., & Holtzman, J. A. 2004, ApJS, 152, 175 [Mac04]CrossRefGoogle Scholar
MacArthur, L. A., González, J. J., & Courteau, S. 2009, MNRAS, 395, 28 [Mac09]CrossRefGoogle Scholar
Maraston, C. 2005, MNRAS, 362, 799CrossRefGoogle Scholar
Morelli, L. et al. 2008, MNRAS, 389, 341CrossRefGoogle Scholar
Thomas, D., Maraston, C., Bender, R., & Mendes de Oliveira, C. 2005, ApJ, 621, 673CrossRefGoogle Scholar
Thomas, D. & Davies, R. L. 2006, MNRAS, 366, 510CrossRefGoogle Scholar