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arXiv · 1512.03151

Extending the $H\alpha$ survey for the local volume galaxies

I. D. Karachentsev·S. S. Kaisin·E. I. Kaisina
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Abstract

Images in the $H\alpha$ emission line are presented for 35 nearby objects observed with the 6-m BTA telescope. Three of them, NGC 3377, NGC 3384, and NGC 3390, are bright E and S0 galaxies, one is an edge-on Sd galaxy UGC 7321, two are remote globular clusters associated with M 31, and the rest are dwarf galaxies of morphological types dIr, dTr, dSph, BCD, and Sm. The measured $H\alpha$ fluxes are used to estimate the integral $(SFR)$ and specific $(sSFR)$ star formation rates for these galaxies. The values of $\log[sSFR]$ for all these objects lie below a limit of $-0.4$(Gyr$^{-1})$. We note that the emission disk for the nearest superthin edge-on galaxy UGC 7321 has an extremely large axis ratio of $a/b = 38.$

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I. D. Karachentsev, S. S. Kaisin, E. I. Kaisina. 2015-12-10. Extending the $H\alpha$ survey for the local volume galaxies. https://arxiv.org/abs/1512.03151

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