Kinematics of an isolated galaxy, CIG 993

TL;DR

This study uses high-resolution Fabry-Perot interferometry to analyze the complex kinematics of the isolated galaxy CIG 993, revealing a rotating disk with central outflows and signs of recent interaction affecting its star formation.

Contribution

First detailed kinematic analysis of CIG 993 showing multiple components and outflows, highlighting the impact of minor interactions on galaxy dynamics and star formation.

Findings

Velocity gradients indicate a rotating disk contrary to previous lower-resolution studies.

Presence of broad and narrow velocity components suggests central outflows.

Galaxy shows signs of recent interaction influencing star formation and kinematics.

Abstract

We present scanning Fabry-Perot interferometric observations of CIG 993, an apparently isolated luminous infrared galaxy also exhibiting luminous blue compact and Wolf-Rayet galaxy features, as well as high star formation rate. Our high resolution observations of the H$\alpha$ emission line allowed us to derive the radial velocity field, as well as the velocity dispersion $\sigma$, and the residual velocity fields of the galaxy. This galaxy exhibits several kinematical components. On one hand, the velocity gradients detected on the velocity field can be associated with a rotating disk -contrary to previous results with less spectral resolution-. However, the velocity field, the $\sigma$ and residual velocity field show significant deviations from circular motions in the central part of the galaxy that matches a region with high number of Wolf-Rayet and O stars, coincident with the blue luminous component of the galaxy. We find narrow and broad velocity components for the ionized gas in the central part of the galaxy. The broad component is evidence of a central outflow related with the on-going burst of stellar formation. The morpho-kinematical analysis of the galaxy indicates we are only seeing the brightest parts of the galaxy which correspond to the bulge, a central bar and the beginning of the disk. We believe CIG 993 is a disk galaxy harboring important star-forming processes most likely caused by a relatively recent interaction. This could imply that small encounters could change the global characteristics of a galaxy without disturbing the main rotation disk motion, nor the morphology of the galaxy.