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Star Formation Histories of Nearby Elliptical Galaxies. II. Merger Remnant Sample

Justin H. Howell
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Abstract

This work presents high $S/N$ spectroscopic observations of a sample of six suspected merger remnants, selected primarily on the basis of H{\sc i} tidal debris detections. Single stellar population analysis of these galaxies indicates that their ages, metallicities, and $α$-enhancement ratios are consistent with those of a representative sample of nearby elliptical galaxies. The expected stellar population of a recent merger remnant, young age combined with low [$α$/Fe], is not seen in any H{\sc i}-selected galaxy. However, one galaxy (NGC~2534), is found to deviate from the $Z$-plane in the sense expected for a merger remnant. Another galaxy (NGC~7332), selected by other criteria, best matches the merger remnant expectations.

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Justin H. Howell. 2006-02-14. Star Formation Histories of Nearby Elliptical Galaxies. II. Merger Remnant Sample. https://doi.org/10.1086/503103

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