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The kinematics and physical properties for some H II regions to the North-East of NGC 4945**

Van Loon

The kinematics and physical properties for some H II regions to the North-East of NGC 4945** Thumbnail



We study the ionized outflows to the North-East of the edge-on spiral galaxy NGC 4945 with the combination of the Fabry-Perot (FP) and long-slit (LS) observations at the South African Large Telescope (SALT). The FP observation was used to analyse Ha emission, introduce first map of ionized outflows (Ha), continuum, kinematic map (the velocity and velocity dispersion) from some H II regions and SNRs to quantify their impact on the surroundings. Different filaments of ionized gas were traced as well as, bubble shape structure could extended from giant H II region (A3), which shows structure as a feedback onto surroundings. The LS observation introduced the physical properties in these areas with more details by tracing Ha and Hß as recombination lines and ([N II]??6549,6583, [S II]??6717,6731 as forbidden lines. The diagnostic diagram based on two ratios (Ha/[N II] and Ha/[S II]) was used to determine the type of these regions which eject ionized outflows. The determined electron densities in the selected regions show a range of values between 2 to 860 cm-3, the highest value appears in region that shows properties of SNR. The oxygen and nitrogen abundances were calculated by using N2 and N2S2 indices for H II regions and SNRs. The oxygen abundances are stable within (2 - 6) kpc of the galactocentric distance, while the abundance of nitrogen rises with increasing the galactocentric distance. The correlation between oxygen and nitrogen abundances presents a mild negative with high metallicity.

Conference Name 3rd International Scientific Conference of Alkafeel University (ISCKU 2021)
Acceptance Date Jan 11, 2022
Publication Date Jan 11, 2022
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