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arXiv · 1411.1674

A new isolated dSph galaxy near the Local Group

I. D. Karachentsev·L. N. Makarova·D. I. Makarov·R. B. Tully·L. Rizzi
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Abstract

Observations of the highly isolated dwarf spheroidal galaxy KKs 3 = [KK2000] 03 with the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) are presented. We measured the galaxy distance of $2.12\pm0.07$ Mpc using the Tip of Red Giant Branch (TRGB) method. The total blue absolute magnitude of the galaxy is estimated as $M_B = -10.8$ mag. We briefly discuss the star formation history of KKs 3 derived from its colour-magnitude diagram. According to our calculation, the total stellar mass of the galaxy is $2.3\times10^7M_{\odot}$, and most stars (74\%) were formed at an early epoch more than 12 Gyr ago. A full description of the properties of the colour-magnitude diagram requires some extension of star formation in metallicity and age.

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I. D. Karachentsev, L. N. Makarova, D. I. Makarov, R. B. Tully, L. Rizzi. 2014-11-06. A new isolated dSph galaxy near the Local Group. https://doi.org/10.1093/mnrasl%2Fslu181

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