Title: The decline of star formation: Exploring molecular gas, outflows and the early history of star formation
One of the key open questions in galaxy evolution today is how and why galaxies (almost) cease to form stars towards the end of their life cycle. The so-called quenching of star formation has been shown to be driven by a combination of reduced molecular gas fractions and low star-forming efficiencies. However, the detailed physical processes behind regulating these quantities, as well as the associated timescales, remain an active area of research.
I will present new insights into galaxy quenching and the drivers of star formation fluctuations from various angles: Using the first data release of the MaNGA-ARO Survey of CO Targets (MASCOT; Wylezalek et al. 2022), I will investigate the more imminent impact of feedback processes onto molecular gas properties at low redshift in conjunction with ionised gas kinematics and the gas-phase metallicity distribution. Specifically, I will focus on weak outflows within the subset of active galaxies below the Main Sequence. Complementary, I will also report on the JWST Early Release Science program Q3D, which will zoom into strong outflows within luminous quasars at different redshifts (0.4<z<3). Finally, I will address to what extent the present-day star formation in galaxies may be traced back to their early histories of star formation on Hubble timescales. For this purpose, I will reconstruct the star formation histories of massive star-forming SDSS-IV MaNGA galaxies (z~0.04) via full spectro-photometric fitting with the novel stellar population synthesis code Bagpipes (Carnall et al., 2018).