Epoch of Galaxy Quenching 2022

How do the chemical compositions of star forming and quenched galaxies compare? What can we learn about the quenching process from measurements of metallicity in gas and stellar populations (e.g. outflows vs. strangulation)? Do contemporary models accurately reproduce the changes in metallicity of galaxies over the epoch of quenching?

What is the origin of the close connection between galactic star formation and structure/ kinematics/ morphology? How does galactic structure evolve from z ~ 2 to the present? Which processes engender the transition from discs to spheroids (e.g. major and minor mergers vs. violent disk instabilities)? How does this structural evolution impact star formation?

What is the origin of the star-forming main sequence (SFR -M* relation)? How does the main sequence evolve from cosmic noon to the present? What physical processes set the Kennicutt-Schmidt relation between gas surface density and the surface density of star formation rate? How does the gas content of galaxies impact star formation? How does star formation efficiency (and its inverse: depletion time) vary within and between galaxies? What can we learn about quenching from observations and simulations of gas in the IGM, CGM and ISM?

Is AGN feedback needed to quench massive galaxies? If so, by which specific mechanism(s) does it operate (e.g. heating vs. outflows)? What observational evidence exists for each scenario? Is supernova feedback responsible for regulating star formation in low mass galaxies? Are other feedback mechanisms important for galaxy quenching (e.g. cosmic rays, magnetic fields)? How do different feedback processes work together in simulations of galaxy evolution? What physical processes set the peak of the halo mass – stellar mass relation?

How does environment impact the star formation and quenching of central and satellite galaxies? What is the role of the dark matter halo in quenching? By what physical mechanisms do dense cluster environments quench satellite galaxies? Is galactic conformity real? If so, what is the mechanism by which quenching is ‘contagious’?