Halos of Spiral Galaxies. III. Metallicity Distributions

Abstract

(Abriged) We report results of a campaign to image the stellar populations in the halos of highly inclined spiral galaxies, with the fields roughly 10 kpc (projected) from the nuclei. We use the F814W (I) and F606W (V) filters in the Wide Field Planetary Camera 2, on board the Hubble Space telescope. Extended halo populations are detected in all galaxies. The color-magnitude diagrams appear to be completely dominated by giant-branch stars, with no evidence for the presence of young stellar populations in any of the fields. We find that the metallicity distribution functions are dominated by metal-rich populations, with a tail extending toward the metal poor end. To first order, the overall shapes of the metallicity distribution functions are similar to what is predicted by simple, single-component model of chemical evolution with the effective yields increasing with galaxy luminosity. However, metallicity distributions significantly narrower than the simple model are observed for a few of the most luminous galaxies in the sample. It appears clear that more luminous spiral galaxies also have more metal-rich stellar halos. The increasingly significant departures from the closed-box model for the more luminous galaxies indicate that a parameter in addition to a single yield is required to describe chemical evolution. This parameter, which could be related to gas infall or outflow either in situ or in progenitor dwarf galaxies that later merge to form the stellar halo, tends to act to make the metallicity distributions narrower at high metallicity.

arXiv comment20 pages, 8 figures (ApJ, in press)

References in corpus (37)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• Final Results from the Hubble Space Telescope Key Project to Measure the Hubble Constant
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• VLT/UVES Abundances in Four Nearby Dwarf Spheroidal Galaxies: I. Nucleosynthesis and Abundance Ratios
• Age and Metallicity Distribution of the Galactic Bulge from Extensive Optical and Near-IR Stellar Photometry
• Evidence for Stellar Substructure in the Halo and Outer Disk of M31
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• The Charge Transfer Efficiency and Calibration of WFPC2
• WFPC2 Observations of the Hubble Deep Field-South
• VLT/UVES Abundances in Four Nearby Dwarf Spheroidal Galaxies: II. Implications for Understanding Galaxy Evolution
• The Hubble Space Telescope Key Project on the Extragalactic Distance Scale XXIV: The Calibration of Tully-Fisher Relations and the Value of the Hubble Constant
• The Halo Stars in NGC 5128. III: An Inner-Halo Field and the Metallicity Distribution
• A Database of Cepheid Distance Moduli and TRGB, GCLF, PNLF and SBF Data Useful for Distance Determinations
• Evidence for a Significant Intermediate-Age Population in the M31 Halo from Main Sequence Photometry
• Photometry and the Metallicity Distribution of the Outer Halo of M31
• The Metallicity Distribution in the Halo Stars of NGC 5128: Implications for Galaxy Formation
• Models for Old, Metal-Poor Stars with Enhanced alpha-Element Abundances. III. Isochrones and Isochrone Population Functions
• Evidence for the Hierarchical Formation of the Galactic Spheroid
• Hubble Space Telescope Observations of M32: The Color-Magnitude Diagram
• The Age, Extinction and Distance of the Old, Metal-Rich Open Cluster NGC 6791
• Formation of the Galactic stellar halo I. Structure and kinematics
• Dwarf Elliptical Galaxies in the M81 Group: The Structure and Stellar Populations of BK5N and F8D1
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• The Andromeda Project. I. Deep HST-WFPC2 V,I photometry of 16 fields toward the disk and the halo of the M31 galaxy. Probing the stellar content and metallicity distribution
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• The Metallicity Distribution Function of Red Giants in the LMC
• Halos of Spiral Galaxies. I. The Tip of the Red Giant Branch as a Distance Indicator
• The Stellar Populations in the Outer Regions of M33. I. Metallicity Distribution Function
• Deep HST V- and I-Band Observations of the Halo of M31: Evidence for Multiple Stellar Populations
• Photometry and the Metallicity Distribution of the Outer Halo of M31. II. The 30 Kpc Field
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• Near-Infrared Adaptive Optics Imaging of the Central Regions of Nearby Sc Galaxies. II. NGC 247 and NGC 2403
• Resolving the Stellar Population of the Standard Elliptical Galaxy NGC3379

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