For the galaxy NGC 1222 we obtained narrow-band images in the emission lines H, NII 6583, and OIII 5007 at the 2. 5-meter telescope of the Caucasus Mountain Observatory of the Sternberg Astronomical Institute of the Moscow State University, which showed that the ionized gas is located in a limited domain of the central part of the main galaxy and in the satellite to the south–southwest of it. The regions of current star formation are located there, which ionize the gas. The long-slit spectra obtained by us at the 6-meter telescope BTA of the Special Astrophysical Observatory of the Russian Academy of Sciences in two position angles allowed us to draw line-of-sight velocity curves for various components of the ionized gas that revealed themselves in the emission, and as a result, to detect kinematic features in the sites of satellites intrusions, which confirm their accretion origin. A large number of emission lines in the spectra allowed us to apply several methods for estimating the oxygen abundance in the gas (i. e. , the gas metallicity). As a result, we found differences in the metallicity of gas in the satellite at the south–southwest, in the regions of star formation in the central part of NGC 1222 and in the gas feeding them. Thus, inside of the previously acquired extensive low-metallicity gas disk of neutral hydrogen, more oxygen-enriched gas is detected, which appeared as a result of accretion from different sides (from the east and from the south–southwest) of two satellites, and the subsequent star formation induced in the sites of their intrusion.
Proshina et al. (Mon,) studied this question.
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