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POX 186: the ultracompact Blue Compact Dwarf Galaxy reveals its nature

V. Doublier·D. Kunth·F. Courbin·P. Magain
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Abstract

High resolution, ground based R and I band observations of the ultra compact dwarf galaxy POX 186 are presented. The data, obtained with the ESO New Technology Telescope (NTT), are analyzed using a new deconvolution algorithm which allows one to resolve the innermost regions of this stellar-like object into three Super-Star Clusters (SSC). Upper limits to both masses (M\sim 10^5 M_{\odot}) and the physical sizes (\le 60pc) of the SSCs are set. In addition, and maybe most importantly, extended light emission underlying the compact star-forming region is clearly detected in both bands. The R-I color rules out nebular Hαcontamination and is consistent with an old stellar population. This casts doubt on the hypothesis that Blue Compact Dwarf Galaxies (BCDG) are young galaxies.

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V. Doublier, D. Kunth, F. Courbin, P. Magain. 1999-02-19. POX 186: the ultracompact Blue Compact Dwarf Galaxy reveals its nature. https://arxiv.org/abs/astro-ph/9902294

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