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تسجيل مستخدم جديدPeculiarities of the chemical abundance distribution in galaxies NGC 3963 and NGC 7292
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Spectroscopic observations of 32 HII regions in the spiral galaxy NGC 3963 and the barred irregular galaxy NGC 7292 were carried out with the 2.5-m telescope of the Caucasus Mountain Observatory of the Sternberg Astronomical Institute using the Transient Double-beam Spectrograph with a dispersion of 1A/pixel and a spectral resolution of 3A. These observations were used to estimate the oxygen and nitrogen abundances and the electron temperatures in HII regions through modern strong-line methods. In general, the galaxies have oxygen and nitrogen abundances typical of stellar systems with similar luminosities, sizes, and morphology. However, we have found some peculiarities in chemical abundance distributions in both galaxies. The distorted outer segment of the southern arm of NGC 3963 shows an excess oxygen and nitrogen abundances. Chemical elements abundances in NGC 7292 are constant and do not depend on the galactocentric distance. These peculiarities can be explained in terms of external gas accretion in the case of NGC 3963 and major merging for NGC 7292.
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