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H-alpha imaging of the Local Volume galaxies I. The NGC 6946 galaxy group

I. D. Karachentsev·S. S. Kajsin·Z. Tsvetanov·H. Ford
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Abstract

We present new H-alpha imaging of all known dwarf irregular companions to NGC 6946: UGC 11583, KK 251, KK 252, KKR 55, KKR 56, Cepheus 1, KKR 59, and KKR 60. The galaxies span a range of blue absolute magnitudes of [-13.6, -17.6], relative gas content of [0.1, 2.5] M_sun/L_sun, current star formation activity of [0.2, 5.2]10^-2 M_sun yr^-1, and timescale to exhaust the current gas supply of [6, 86] Gyr.

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I. D. Karachentsev, S. S. Kajsin, Z. Tsvetanov, H. Ford. 2005-02-21. H-alpha imaging of the Local Volume galaxies I. The NGC 6946 galaxy group. https://doi.org/10.1051/0004-6361%3A20052673

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