The Chemical Enrichment History of the Large Magellanic Cloud

Abstract

Ca II triplet spectroscopy has been used to derive stellar metallicities for individual stars in four LMC fields situated at galactocentric distances of 3\arcdeg, 5\arcdeg, 6\arcdeg\@ and 8\arcdeg\@ to the north of the Bar. Observed metallicity distributions show a well defined peak, with a tail toward low metallicities. The mean metallicity remains constant until 6\arcdeg\@ ([Fe/H]$\sim$-0.5 dex), while for the outermost field, at 8\arcdeg, the mean metallicity is substantially lower than in the rest of the disk ([Fe/H]$\sim$-0.8 dex). The combination of spectroscopy with deep CCD photometry has allowed us to break the RGB age--metallicity degeneracy and compute the ages for the objects observed spectroscopically. The obtained age--metallicity relationships for our four fields are statistically indistinguishable. We conclude that the lower mean metallicity in the outermost field is a consequence of it having a lower fraction of intermediate-age stars, which are more metal-rich than the older stars. The disk age--metallicity relationship is similar to that for clusters. However, the lack of objects with ages between 3 and 10 Gyr is not observed in the field population. Finally, we used data from the literature to derive consistently the age--metallicity relationship of the bar. Simple chemical evolution models have been used to reproduce the observed age--metallicity relationships with the purpose of investigating which mechanism has participated in the evolution of the disk and bar. We find that while the disk age--metallicity relationship is well reproduced by close-box models or models with a small degree of outflow, that of the bar is only reproduced by models with combination of infall and outflow.

45 pages, 10 figures, accepted for publication in Astronomical Journal

References in corpus (4)

• Dynamics of Barred Galaxies
• Calcium II Triplet Spectroscopy of LMC Red Giants. I. Abundances and Velocities for a Sample of Populous Clusters
• The Infrared Ca II triplet as metallicity indicator
• The Magellanic Squall: Gas Replenishment from the Small to Large Magellanic Cloud

Cited by in corpus (33)

• The Chemical Enrichment History of the Small Magellanic Cloud and Its Gradients
• The dust production rate of AGB stars in the Magellanic Clouds
• A large stellar evolution database for population synthesis studies. IV. Integrated properties and spectra
• Prolate rotation and metallicity gradient in the transforming dwarf galaxy Phoenix
• Red Giants in the Small Magellanic Cloud. II. Metallicity Gradient and Age-Metallicity Relation
• The VMC survey -- XLIII. The spatially resolved star formation history across the Large Magellanic Cloud
• Outside-in disk evolution in the LMC
• The VMC survey -- XLIV: Mapping metallicity trends in the Large Magellanic Cloud using near-infrared passbands
• Chemical Signature of a Major Merger in the Early Formation of Small Magellanic Cloud
• The Most Metal-poor Stars in the Magellanic Clouds are $r$-process Enhanced
• The Second Data Release of the Survey of the MAgellanic Stellar History (SMASH)
• The VMC Survey -- XLII. Near-infrared period-luminosity relations for RR Lyrae stars and the structure of the Large Magellanic Cloud
• Galaxy Satellites and the Weak Equivalence Principle
• Tagging the Chemical Evolution History of the Large Magellanic Cloud Disk
• Evolution of dust and molecular hydrogen in the Magellanic System
• The Magellanic Edges Survey I. Description and First Results
• The VMC survey -- XXXIX: Mapping metallicity trends in the Small Magellanic Cloud using near-infrared passbands
• A homogeneous comparison between the chemical composition of the Large Magellanic Cloud and the Sagittarius dwarf galaxy
• Metallicities and ages for star clusters and their surrounding fields in the Large Magellanic Cloud
• The beat Cepheids in the Magellanic Clouds: an analysis from the EROS-2 database
• The most metal-rich stars in the universe: chemical contributions of low and intermediate mass asymptotic giant branch stars with metallicities between $0.04\le Z\le \mathrm{0.10.}$
• On the Color-Metallicity Relation of the Red Clump and the Reddening Toward the Magellanic Clouds
• A very dark stellar system lost in Virgo: kinematics and metallicity of SECCO1 with MUSE
• From K giants to G dwarfs: stellar lifetime effects on metallicity distributions derived from red giants
• The RR Lyrae Delay-Time Distribution: A Novel Perspective on Models of Old Stellar Populations
• Short period variability in the globular cluster NGC 419 and the SMC field
• Kinematics of a globular cluster with an extended profile: NGC5694
• The open cluster King~1 in the second quadrant
• A segmented period-luminosity relation for nearby extragalactic $\delta$ Scuti stars
• Chemo-Dynamical Tagging in the Outskirts: The Origins of Stellar Substructures in the Magellanic Clouds
• Revisiting the near infrared Calcium triplet as metallicity indicator
• The Chemical Enrichment History of the Magellanic Clouds Field Populations
• The Metallicity Distribution Function in Outer Halo Fields of Simulated Elliptical Galaxies Compared to Observations of NGC 5128