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arXiv · 1206.5585

H-alpha survey of nearby dwarf galaxies

S. S. Kaisin·I. D. Karachentsev·S. Ravindranath
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Abstract

We present the H-alpha imaging data and flux measurements for 30 dwarf galaxies in the Local volume. The H-alpha fluxes are used to derive the galaxy star formation rate, SFR. The sample of observed galaxies is characterized by the following parameters: the median distance of 7.5 Mpc, the median blue absolute magnitude of -14.8 mag, and median SFR of -2.0 dex. Two dSph members of the Local Group: Cetus and Leo IV do not show signs of star formation on the rate of -5.4 dex and -7.0 dex, respectively. The BCD galaxy ESO 553-46 has one of the highest specific SFR among the Local volume galaxies.

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S. S. Kaisin, I. D. Karachentsev, S. Ravindranath. 2012-06-25. H-alpha survey of nearby dwarf galaxies. https://doi.org/10.1111/j.1365-2966.2012.21501.x

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