Characterizing the Multi-Phase Interstellar to Intergalactic Medium of Distant, Active Galaxies

Our understanding of the interstellar and circumgalactic medium of distant galaxies is constantly growing. In particular, detections of the emission/absorption lines tracing a wide range of phases in the interstellar and circumgalactic medium of distant galaxies enables a wide variety of studies of the warm ionized gas to the diffuse or dense cold neutral medium. As ALMA begins routinely detecting both ionized and neutral gas tracers from high redshift galaxies, JWST will undoubtedly detect rest-frame far-UV to near-IR tracers to provide an expansive multi-wavelength perspective on galaxy evolution for a near-infrared to sub-mm perspective. As models advance to match the data, we will need new analyses to characterize galaxies with multi-wavelength observations to make sense of how this information can help to understand the rapid build-up of star formation processes in high redshift galaxy evolution (e.g. z>1 ). Sensitive instruments will allow for detailed studies of unlensed galaxies, but when matched with the hundreds to thousands of strongly lensed objects in the sky, the current suite of facilities will allow for the detection of a plethora of lines to examine galaxy evolution in great detail over the next decade.

The purpose of this Research Topic is to collect a mix of articles to explore the ways in which new cosmological and galaxy evolution simulations compare and contrast with the latest advancements in observational data.

We aim to collect new perspectives to provide insight into the amount and origin of the expected radiation from various phases of the multi-phase media in and around actively forming galaxies in the distant universe.

Authors may submit, but are not limited to, articles on the following topics:

- L* galaxies at z>1 detected in both CO and C+ and N+ by ALMA
- The environment around quasars, e.g. traced by Lyman-alpha emission
- Galaxies within and approaching the epoch of reionization (roughly z>5) or the peak epoch of cosmic star formation (z~1-3)
- The role of far-IR fine-structure lines in providing diagnostics of the star-forming interstellar medium at z>1
- Starburst galaxies and the nature of their extreme activity
- The varying functional roles of cosmic rays, X-rays, shocks, turbulence and other radiative and mechanical processes in distant, active galaxies
- The role of stellar and AGN feedback in shaping SF in active galaxies
- Low-z studies of active galaxies which directly compare to high redshift systems

We welcome a range of article types in this Research Topic, including Original Research and Review.

Keywords: interstellar medium (ISM), galaxy evolution, star-formation, radiative transfer, turbulent gas, cold gas, circumgalatic medium, high redshift, starbursts, active galactic nuclei

Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.