Open Questions on Dust, Cold Gas, Star Formation, and Feedback in Nearby Galaxies

Determine the formation mechanisms and properties of interstellar dust and cold gas phases in nearby galaxies; ascertain the processes that lead to star formation activity in those cold phases and quantify the local fraction of gas mass converted into stars and the time scale for such conversion; and characterize the feedback mechanisms that regulate star and black hole formation and drive galaxy growth on intermediate and large spatial scales.

Background

The report emphasizes nearby galaxies as prime laboratories for studying the baryon cycle because they allow high spatial resolution and sensitivity. Within this context, the authors explicitly list several open questions concerning the formation and properties of interstellar dust and cold gas, the processes that control star formation efficiency and timescales, and the feedback mechanisms that influence both star and black hole formation and thus galaxy growth.

Addressing these questions requires observations across cm-to-FIR wavelengths, including polarimetry and spectroscopy, and motivates enhanced capabilities in facilities such as ALMA, ngVLA, and potential FIR space missions.