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arXiv · 1301.1339

An intermediate-band photometric study of the "Globular Cluster" NGC 2419

Andreas Koch·Matthias Frank·Sofia Feltzing·Daniel Aden·Nikolay Kacharov·Mark I. Wilkinson
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Abstract

NGC 2419 is one of the remotest star clusters in the Milky Way halo and its exact nature is yet unclear: While it has traits reminiscent of a globular cluster (GC), its large radius and suggestions of an abundance spread have fueled the discussion about its origin in an extragalactic environment, possibly the remnants of the accretion of a dwarf galaxy. Here, we present first results from deep intermediate-band photometry of NGC 2419, which enables us to search for chemical (light element) abundance variations, metallicity spreads, and thus multiple stellar populations through well calibrated Stroemgren indices.

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Andreas Koch, Matthias Frank, Sofia Feltzing, Daniel Aden, Nikolay Kacharov, Mark I. Wilkinson. 2013-01-07. An intermediate-band photometric study of the "Globular Cluster" NGC 2419. https://arxiv.org/abs/1301.1339

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