RSAA Colloquia / Seminars / Feast-of-Facts: Friday, 28 November 2014, 14:20-14:40; Duffield Lecture Theatre

Tomas Ruiz-Lara

"Unveiling the stellar content in the outer parts of spiral galaxies"

In the recent years, the interest on studying the outer parts of spiral galaxies is rising. To better understand galactic formation and evolution, simulations and observations are working together to understand the different behaviours that the disc light distribution displays in the outer parts of these systems. During this talk I will speak about my current work as part of my PhD project focused on the stellar content in these outer regions. We have implemented a new methodology to analyse the stellar content from spectroscopic data based on the state-of-art full spectrum fitting techniques (using GANDALF and STECKMAP). We have tested such methodology on the LMC bar region, where high quality integrated spectra can be obtained as well as Color-Magnitude Diagrams reaching the oldest Main Sequence Turnoff. I will also show the first results that we are obtaining when applying such methodology to the smallest galaxies observed in the CALIFA (Sanchez et al. 2012) and SAMI (Croom et al. 2012) surveys. I will compare such observational results with what recent simulations (RaDES, Few et al. 2012) suggest. I will finish showing the effect that satellite accretion has on shaping the chemical and kinematic properties of the outskirts of simulated galaxies, as well as the effect of such accretion in the shape of the stellar age profile as shown by the RaDES set of galaxies.