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تسجيل مستخدم جديدRelations between abundance characteristics and rotation velocity for star-forming MaNGA galaxies
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We derive rotation curves, surface brightness profiles, and oxygen abundance distributions for 147 late-type galaxies using the publicly available spectroscopy obtained by the MaNGA survey. Changes of the central oxygen abundance (O/H)_0, the abundance at the optical radius (O/H)_R25, and the abundance gradient with rotation velocity V_rot are examined for galaxies with rotation velocities from 90 km/s to 350 km/s. We found that each relation shows a break at V_rot^* ~200 km/s. The central (O/H)_0 abundance increases with rising V_rot and the slope of the (O/H)_0 - V_rot relation is steeper for galaxies with V_rot < V_rot^*. The mean scatter of the central abundances around this relation is 0.053 dex. The relation between the abundance at the optical radius of a galaxy and its rotation velocity is similar; the mean scatter in abundances around this relation is 0.081 dex. The radial abundance gradient expressed in dex/kpc flattens with the increase of the rotation velocity. The slope of the relation is very low for galaxies with V_rot > V_rot^*. The abundance gradient expressed in dex/R25 is rougly constant for galaxies with V_rot < V_rot^*, flattens towards V_rot^*, and then again is roughly constant for galaxies with V_rot > V_rot^*. The change of the gradient expressed in terms of dex/h_d (where h_d is the disc scale length) with rotation velocity is similar to that for gradient in dex/R25. The relations between abundance characteristics and other basic parameters (stellar mass, luminosity, and radius) are also considered.
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