Speaker
Description
Galaxy formation and evolution involve complex physical processes and understanding how galaxies evolve through cosmic time remains a fundamental question in astrophysical research. Star formation (SF), one of the most important processes is essential to the formation and evolution of galaxies. A measure of the rate of star formation, along with other properties of a galaxy such as the stellar mass, are obtained through fitting SED (spectral energy distribution) models to multi-wavelength spectrophotometric observational data of the galaxy. This allows for SFR calibrations of luminosities at various wavelengths.
The Hα emission line stands out as the best tracer of SF coming from HII regions ionized by massive stars. However such lines can also arise from these same massive stars heated by Active Galactic Nuclei (AGN), hence SFR calibrations based on Hα line can be overestimated by the presence of an AGN if the AGN’s contribution is not taken into account.
In this project, we aim to study the effect of AGN on the SFR of its host galaxy. We will use the Python-based code, CIGALE (Code Investigating GALaxy Emission), a state-of-the-art galaxy SED-fitting model relying on energy balance, to compute the contribution of an AGN in a self-consistent manner in estimating the SFR of a statistically significant sample of nearby star-forming galaxies. This will be followed by a comparative analysis of the AGN contributions obtained from other independent methods such as line ratio diagnostic diagrams and those obtained with other SED-fitting models. Correlations between the AGN X-ray luminosity and SFR will be searched for. The analytical component of the project will also involve some level of computing/modeling.
| Stream | Science |
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