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arXiv · 1401.2719

Three low surface brightness dwarfs discovered around NGC 4631

Igor D. Karachentsev·Dirk Bautzmann·Fabian Neyer·Robert Polzl·Peter Riepe·Thorsten Zilch·Bruno Mattern
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Abstract

We report the discovery of three low surface brightness companions to the spiral galaxy NGC 4631, made with small amateur telescopes. Assuming their distances to be 7.4 Mpc, the same as that of NGC 4631, the absolute magnitudes and linear diameters of the dwarfs are ranged within [-12.5, -9.6] mag and [4.7 - 1.3] kpc, respectively. These new three dwarfs, together with the discovered by us diffuse structure called "bridge", look like parts of a tidal filament directed towards NGC 4656 at total extended over 100 kpc.

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Igor D. Karachentsev, Dirk Bautzmann, Fabian Neyer, Robert Polzl, Peter Riepe, Thorsten Zilch, Bruno Mattern. 2014-01-13. Three low surface brightness dwarfs discovered around NGC 4631. https://arxiv.org/abs/1401.2719

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