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arXiv · 1808.04508

Internal Kinematics of UM 461 and CTS 1020

Maiara S. Carvalho·Henri Plana
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Abstract

We have used integral field spectroscopy to study the internal kinematics of the H\,{\sc ii} galaxies CTS 1020 and UM 461. We based our analysis on the velocity and velocity dispersion maps, and intensity-velocity dispersion ($I-\sigma$) and velocity-velocity dispersion ($V_r-\sigma$) diagrams. We found that the motion in both star-forming knots of UM 461 has different patterns, suggesting a weak kinematical connection between the knots. The overall kinematics of the galaxy is probably affected by stellar feedback. CTS 1020 has an ordered motion with a gradient compatible with a disc rotating at $\sim50$ km s$^{-1}$, though the velocity field is disturbed. In both galaxies the highest and lowest $\sigma$ values are distributed in the outer parts and are associated with the diffuse gas that permeates the galaxies. UM 461 has a ring-like structure with small regions of increasing $\sigma$ in the eastern knot, which resemble what we could expect in a collect and collapse scenario of star formation. We found that UM 461 seems to be more susceptible to stellar feedback, whereas in CTS 1020 the gravitational potential dominates.

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Maiara S. Carvalho, Henri Plana. 2018-08-14. Internal Kinematics of UM 461 and CTS 1020. https://doi.org/10.1093/mnras%2Fsty2229

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