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The Outer Halo Cluster System of NGC 1399

B. Dirsch·D. Geisler·T. Richtler·J. C. Forte
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Abstract

We investigate the outer halo globular cluster population of NGC 1399. This study uses wide-field imaging of this cluster system, which covers the largest area studied with CCD photometry until now. The cluster system of NGC 1399 is found to extend further than 100 kpc from the galaxy. A population of metal-rich, as well as metal-poor clusters has been identified at these large radii. At radii smaller than 55 kpc the specific frequency of the red cluster system remains constant, while that of the blue clusters increases proportional to $r^{0.8\pm0.2}$. For larger radii, the uncertainty of the galaxy light profile does not permit any reliable statement.

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B. Dirsch, D. Geisler, T. Richtler, J. C. Forte. 2001-09-12. The Outer Halo Cluster System of NGC 1399. https://arxiv.org/abs/astro-ph/0109192

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