Name: Meera Nandakumar
Affiliation: Research Scholar, Department of Physics, Indian Institute of Technology (BHU) Varanasi (IIT BHU)
Conference ID : ASI2022_138
Title : Understanding interstellar turbulence and it's implications in external spiral galaxy NGC~5236
Authors : Meera Nandakumar, Prasun Dutta
Abstract Type: Oral
Abstract Category : Extragalactic Astronomy
Abstract : Turbulence plays an important role in the structure and dynamics of the galaxy and influences various processes therein including star formation. In this work, we investigate the large-scale turbulence properties of the external spiral galaxy NGC 5236. We estimate the \HI column density and line of sight velocity fluctuation power spectra for this galaxy over almost two decades of length scales. The energy input scale to the ISM turbulence is found to be around 6 kpc. The measured power spectra follow a power law with slopes strongly in favour of a compressive force. We conclude that much of the measured turbulence originates from the gravitational instabilities and self-gravity in the disk. This is the first and most comprehensive study of turbulence statistics for any external spiral galaxy. We also investigated the influence of ISM turbulence in the star formation process, where we carried out investigating the disk instability by implementing modified Toomre-like criteria in the galaxy. We could probe unstable regions in the disk locally and tried to quantify their relation to regions of high star formation. Results of the same will be presented here.