ESO 540 - 032 : a Transition - Type Dwarf in the Sculptor Group
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Tip of the Red Giant Branch Distance for the Sculptor Group Dwarf ESO 540 - 032 ?
We present the first V I CCD photometry for the Sculptor group galaxy ESO 540-032 obtained at the Very Large Telescope UT1+FORS1. The (I, V − I) colour-magnitude diagram indicates that this intermediatetype dwarf galaxy is dominated by old, metal-poor ([Fe/H]≈ −1.7 dex) stars, with a small population of slightly more metal-rich ([Fe/H]≈ −1.3 dex), young (age 150 − 500 Myr) stars. A discontinuit...
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We present an analysis of Hubble Space Telescope/WFPC2 images of nine nearby galaxies in Sculptor. We derive their distances from the luminosity of the tip of the red giant branch stars with a typical accuracy of ∼ 12 %. Their distances are 4.21 Mpc (Sc 22), 4.92 Mpc (DDO 226), 3.94 Mpc (NGC 253), 3.40 Mpc (KDG 2), 3.34 Mpc (DDO 6), 3.42 Mpc (ESO 540-030), 4.43 Mpc (ESO 245–05), 4.27 Mpc (UGCA ...
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