›Sweeping galaxies clean: cold molecular outflows as drivers of galaxy evolution

Abstract

In order to produce the galaxy populations we see around us in the universe today, modern theories of galaxy formation require processes that regulate and slow galaxy growth. Massive outflows powered by star formation and active galactic nuclei (AGN) are often evoked to fulfill this role. Observationally, the study of such outflows has recently come of age. A series of studies have shown that both AGN and star formation can drive gas from galaxies: both the tenuous gas phases, and crucially also the cold molecular gas. This gives outflows the potential to strongly impact the evolution of the host galaxy, regulating the amount of cold and dense gas available for star formation and black hole accretion.

Despite the progress that has been made in this area, many open questions remain about the physical processes involved. For instance:

the amount of mass ejected from galaxies is unclear. Are outflows strong enough to regulate star formation (or are they too strong)? 


what are the ejection mechanism(s) and the coupling between the phases in the ejecta? 


what is the the lifetime of cold gas in the outflow? 


what is the impact on the enrichment of the ISM and the redistribution of gas within galaxy disks?

The future of this field is bright, with a large range of new observing facilities currently coming online (e.g. ALMA, NOEMA, JVLA). However, to advance our fundamental under- standing of this challenging topic requires the combined input of theoreticians, simulators, and observers. This timely meeting thus aims to bring together experts from all disciplines working on massive molecular outflows in galaxies to discuss these open issues. This will be a small, dedicated workshop with presentations, but also a substantial amount of time dedicated to informal discussion and work sessions.

Organiser

Timothy A. Davis
SOC: Timothy A. Davis (SOC Chair: University of Hertfordshire, UK), Susanne Aalto (Chalmers University of Technology, SE), Alberto Bolatto (University of Maryland, USA), Crystal Martin (University of California, Santa Barbara, USA), Norman Murray (CITA, CA)