Dynamical resonances of bars in PHANGS galaxies

Bars are remarkable stellar structures, which play an essential role in driving the secular evolution of galaxies, as they are expected to transport the gas towards the centre. In this study NIR images and ALMA CO(2-1) maps from the PHANGS survey are used to trace the stellar potential and the molecular gas distribution to determine the position of the main dynamical resonances of the bars in our targets. In this work, the gravitational torque method from García-Burillo et al. (2005) is used to locate the position of the corotation (CR), where stars and gas rotate at the same angular velocity as the bar. We have established the position of corotation for the 43 barred galaxies of the sample, which is composed of a total of 74 galaxies. Furthermore, a distinction has been made between fast and slow bars, by measuring R_CR/R_bar for every galaxy. We found that this variable has a mean value of 1.23 and standard deviation of 0.55, which is consistent with the value expected from theory R_CR/R_bar=1.2. Finally, we have also estimated other relevant resonances such as the Inner Lindblad Resonance (ILR) and the Outer Lindblad Resonance (OLR), where rings are expected to be formed. In this talk, we give an glimpse at our work, which provides a useful catalogue of resonances for nearby galaxies and emphasises the connection between bar dynamics and morphology, as the existence of fast and slow bars has cosmological implications for a scenario where bars may brake over time