演講資訊

摘要：

Non-axisymmetric structures in galaxies such as stellar bars, bulges, and spiral arms induce perturbations to an axisymmetric potential. The kinematic effect of such perturbation is that gas and stars on the disk of spiral galaxies suffer deviations of the circular rotation. When computed at different galactocentric distances, such circular velocity describes the so-called rotational curve. However, in the presence of potential perturbations the circular velocity measured from the velocity map no longer describes the "circular rotation". In this talk, I will show the effects of stellar bars on the velocity field of galaxies, using data from different IFS-galaxy surveys, i.e., MUSE, CALIFA and MaNGA. I will show that bars induce kinematic distortions in the velocity field of disk galaxies, and such oval-distortions can be described by non-circular rotation models. I will show the implementation of Bayesian codes for reproducing the kinematics of galaxies with non-axisymmetric components. Since stellar bars arise as a consequence of a second-order perturbation in the potential, I will show that the kinematic of these galaxies can be described by bisymmetric models and a harmonic decomposition of the LoS velocities for a second-order perturbation. Moreover, the position oval of the distortion is aligned with the photometric position angle of the galaxies. Finally, I show that kinematics is crucial for detecting bars in galaxies, even when these are not detected in the optical or IR bands.