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arXiv · 1704.07648

DDO 161 and UGCA 319: an isolated pair of nearby dwarf galaxies

I. D. Karachentsev·L. N. Makarova·R. B. Tully·L. Rizzi·V. E. Karachentseva·E. Shaya
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Abstract

We report HST/ACS observations of two nearby gas-rich dwarf galaxies: DDO 161 and UGCA 319. Their distances determined via the Tip of the Red Giant Branch are 6.03 (-0.21/+0.29) Mpc and 5.75+-0.18 Mpc, respectively. The galaxies form an isolated pair dynamically well separated from the nearest neighbors: KK 176 (7.28+-0.29 Mpc) and NGC 5068 (5.16+-0.21 Mpc). All four galaxies have a bulk spatial peculiar velocity towards the Virgo cluster of ~158+-17 km/s in the Local Group rest frame and ~330 km/s with respect to the cluster center.

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I. D. Karachentsev, L. N. Makarova, R. B. Tully, L. Rizzi, V. E. Karachentseva, E. Shaya. 2017-04-25. DDO 161 and UGCA 319: an isolated pair of nearby dwarf galaxies. https://doi.org/10.1093/mnrasl/slx061

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