Speaker
Description
Numerous theoretical studies within the modern cosmological framework suggest that gas accretion from the intergalactic medium is essential to feed star formation in galaxies throughout cosmic time. However, the way gas accretion takes place is still poorly understood as a direct evidence of it is still lacking. In some models, gas accretion is expected to take place in the outer discs of galaxies, from where it should be transferred to the inner star-forming discs through radial flows. Finding such flows and quantify them opens, therefore, the exciting possibility to infer the detailed properties of the accreting gas. Unfortunately the detection of radial flows presents a significant challenge due to the magnitude disparity between the radial and rotational velocities. Additionally, the distortions in velocity fields produced by these flows bear similarities to the effects of warped structures, further complicating their quantification. To address this, we have developed a new methodology to measure radial velocities and quantify mass flow rates in disc galaxies. This method employs the 3D kinematic software, 3D-Barolo, and incorporates a bootstrapping approach to estimate errors. We validated this approach using mock data from local galaxies in hydrodynamic simulations. In our analysis, we found that some galaxies exhibit azimuthal uniform radial inflows, but other galaxies display non-uniform radial flows, with variations in flow patterns. We also applied the method to some local galaxies and examined whether radial accretion inflows alone are sufficient to maintain the current rate of star formation in the inner regions of local spiral galaxies.
| Talk category | NOVA Network 1 |
|---|---|
| Preference for a talk or poster | Talk |
| Talk preference for PhD students | Third Year |
