Austrian Early Career Conference 2024

Contribution:
Poster

Authors:
J.Stoiber; L. Valenzuela; L. Kimmig; R.-S. Remus

Affiliations:
Universitäts-Sternwarte München

Title:
Chemical Properties, Age- and Metallicity Gradients of Simulated Galaxies

Abstract:
Photometric and integral field unit observations of the stellar component have shown galaxies to come in a large variety of morphologies and kinematics. By applying population synthesis techniques, it is possible to determine spatially resolved age and metallicity distributions.
Using the hydrodynamical cosmological simulation Magneticum, we analyze the global age properties of galaxies and investigate their correlations with the radial distribution of metallicity.
We classify the galaxies as disks, intermediates, and spheroids via the b-value, which is a proxy for a galaxy's position in the stellar mass - stellar specific angular momentum plane. Global properties of the galaxies are determined and radially binned to analyze age and metallicity gradients. Their stellar content is subdivided into an old, middle-aged, and young population. Correlations of the radial distribution of metallicities with global properties are then calculated, while their slopes are taken from a fit to radially binned data. The results are compared to observations from the SAMI, CALIFA, MaNGA, ALHAMBRA and TYPHOON surveys.
I will show that, while age correlates with morphology, metallicity correlates stronger with mass. As expected, disks are more rotationally supported than spheroids. In agreement with observations, I demonstrate the general trend that the age of galaxies increases with mass and that spheroids, on average, are older than the disks, at a fixed mass. The mass-size relation stays consistent with observations when split into the different age populations. Another important relation, the mass-metallicity relation is in general agreement with observations.
A slightly positive average age gradient in spheroids suggests an "outside-in" formation scenario, while disks, on average, have a negative central age gradient, suggesting an "inside-out" growth. Also, on average, the young and old stellar populations exhibit a different slope of the radial metallicity distribution. Our investigation reveals that the metallicity of the old population is rather loosely correlated with the radius, but always negatively. The young population’s correlations range from tight to loose and critically can be both negative or positive.