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arXiv · 0910.1919

Gas Emission Spectrum in the Irr Galaxy IC 10

T. A. Lozinskaya·O. V. Egorov·A. V. Moiseev·D. V. Bizyaev
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Abstract

Spectroscopic long-slit observations of the dwarf Irr galaxy IC 10 were conducted at the 6-m Special Astrophysical Observatory telescope with the SCORPIO focal reducer. The ionized-gas emission spectra in the regions of intense current star formation were obtained for a large number of regions in IC 10. The relative abundances of oxygen, N+, and S+ in about twenty HII regions and in the synchrotron superbubble were estimated. We found that the galaxy-averaged oxygen abundance is 12 + log(O/H) = 8.17 +- 0.35 and the metallicity is Z = 0.18 +- 0.14 Z_sun. Our abundances estimated from the strong emission lines are found to be more reliable than those obtained by comparing diagnostic diagrams with photoionization models.

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T. A. Lozinskaya, O. V. Egorov, A. V. Moiseev, D. V. Bizyaev. 2009-10-11. Gas Emission Spectrum in the Irr Galaxy IC 10. https://doi.org/10.1134/s1063773709110024

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