Maria Koller

I am highly interested in galaxy evolution at intermediate redshifts of z~0.3 with my main focus being on the fundamental metallicity relation (FMR). This three-dimensional relation connects stellar mass, star formation rates (SFRs), and gas-phase metallicities and is characterized by the gas interplay of the galaxy. The SFR is tightly regulated by the amount of gas present in the galaxy. From the intergalactic medium, pristine (metal-poor) gas constantly flows into the galaxy, adding fuel for star formation and diluting the enriched gas, essentially decreasing the metallicity. After some time, gas is returned by the death of stars that also produce metals increasing the gas-phase metallicity. Some gas can be expelled from the galaxy via outflows caused by winds depleting the metal content of the gas. During the start of their life, galaxies will typically have high SFRs, low masses, and low gas-phase metallicities. As the galaxy ages, it will increase in mass and metallicity.  

Within my Master's thesis, I am investigating the FMR in a spatially resolved way to gain insight into the galaxies' gas evolution. My sample of 12 galaxies stems from the Middle Ages and Galaxy Properties with Integral Field Spectroscopy (MAGPI) survey. Their observations were taken with the MUSE instrument of the VLT with the main objective of the survey being the dissection of the evolutionary pathways galaxies take at 3-4 Gyr lookback-time by investigating their stellar and gaseous content simultaneously. The use of their data has also granted me team membership. Using the population spectral synthesis code FADO, I measure the emission lines fluxes for each pixel spectra of each galaxy and obtain their stellar mass surface densities. A full analysis of the ionized gas is then conducted: diagnostic diagrams to determine the galaxies' main ionizing mechanisms are created, SFR surface densities are computed and gas metallicities are estimated. Putting all these together, I will achieve an analysis of the resolved FMR of galaxies at z~0.3. For local galaxies, this relation has already been well studied on both global and local scales, therefore, my results at z~0.3 could serve as a benchmark between the local universe and higher redshifts.