Gas Inflows to the nucleus of galaxies 

What causes the gas to flow in?

Gas clouds along the bar of a galaxy can interact with each other due to forces/torques exerted by the bar. Consequently, this interaction cause gas to lose its momentum, and to get shocked which then the shocked gas starts funnelling to inner regions of the galaxies. We call this phenomenon, the gas inflows. The role of gas inflows in the evolution of galaxies is significant, inflows can change the morphology of the central regions, enhance nuclear star formation, and cause nuclear feeding, AGN feedback and quenching. 

Although we understand how gas flow from the outer regions of galaxies to the central regions, due to gravitational effects (e.g. bar driven), we still are puzzled by how gas is being carried to the very core of the galaxies from the central regions. 

Theoretical studies and models tell us that gas inflows occur as coherent structures in kinematic maps in response to the stellar gravitational potential. So, in my project, I derive the gas kinematics (velocity and velocity dispersion fields) from revolutionary data from the MUSE integral-field-unit instrument and search for identifying these coherent features in kinematic maps. 

By modelling a simple circular rotating model of gas, and removing it from the observed velocity field of a galaxy, we can find where the gas is behaving non-circularly, which the continuous features in the remaining velocity field can be interpreted as the shocked gas.

Insight into integral field units

Integral-field units are ideal instruments to capture extended objects like galaxies. They capture 2D spatial information and get the 3rd dimension from the spectrograph as wavelength information.