The fate of the gas in galaxies workshop

摘要

Gas plays an essential role in the formation and evolution of galaxies. The dynamical structure of galaxies can only be understood if dissipative mergers and accretions are included in the models. Even for early-type galaxies, traditionally considered to be gas-poor, the role of gas cannot be neglected. At the same time, it is clear that the ongoing accretion of gas is crucial for understanding the evolution of spiral galaxies, including our own Galaxy. To complicate matters, it now appears that the energetic feedback from both AGN and central star-bursts on the gas could be one of the main factors determining the final structure of galaxies. Finally, the medium in which galaxies are embedded may affect the fate of the gas. Galaxies in low-density environments continue to accrete gas while in dense clusters, the cold gas gets removed from the galaxies (see Fig. 1).