ALMA2040: The High-Redshift Circumgalactic Medium. Imaging the fueling and feedback of galaxies in the early universe

@misc{butler2026alma2040,
  title = {{ALMA2040: The High-Redshift Circumgalactic Medium. Imaging the fueling and feedback of galaxies in the early universe}},
  author = {Kirsty M. Butler and Justin Spilker and Seiji Fujimoto and Manuel Aravena and Cecilia Bacchini and Leindert A. Boogaard and Stefano Carniani and Chiara Circosta and Pierre Cox and Rebecca Davies and Tanio Diaz-Santos and Daniel Espada and Andreas Faisst and Jonathan Freundlich and Mahsa Kohandel and Andrea Lapi and Umberto Maio and Dieu D. Nguyen and Andrea Pallottini and Mamta Pandey-Pommier and Antonio Pensabene and Miguel Pereira-Santaella and Matus Rybak and Francesco Salvestrini and Livia Vallini and Anita Zanella},
  howpublished = {arXiv},
  year = {2026},
  month = oct,
  doi = {10.48550/arxiv.2610.21776},
  eprint = {2610.21776},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2610.21776},
  note = {CC BY 4.0},
}

TY  - UNPB
TI  - ALMA2040: The High-Redshift Circumgalactic Medium. Imaging the fueling and feedback of galaxies in the early universe
AU  - Kirsty M. Butler
AU  - Justin Spilker
AU  - Seiji Fujimoto
AU  - Manuel Aravena
AU  - Cecilia Bacchini
AU  - Leindert A. Boogaard
AU  - Stefano Carniani
AU  - Chiara Circosta
AU  - Pierre Cox
AU  - Rebecca Davies
AU  - Tanio Diaz-Santos
AU  - Daniel Espada
AU  - Andreas Faisst
AU  - Jonathan Freundlich
AU  - Mahsa Kohandel
AU  - Andrea Lapi
AU  - Umberto Maio
AU  - Dieu D. Nguyen
AU  - Andrea Pallottini
AU  - Mamta Pandey-Pommier
AU  - Antonio Pensabene
AU  - Miguel Pereira-Santaella
AU  - Matus Rybak
AU  - Francesco Salvestrini
AU  - Livia Vallini
AU  - Anita Zanella
PY  - 2026
DA  - 2026/10/15
PB  - arXiv
DO  - 10.48550/arxiv.2610.21776
UR  - https://arxiv.org/abs/2610.21776
AB  - Galaxies do not form in isolation, but rather as part of a wider interconnected web mediated at their interface by an extended gaseous atmosphere - the Circum-Galactic Medium (CGM). This dynamic and multiphase region is fed and shaped by gas inflows and mergers from the intergalactic medium and by feedback-driven outflows and radiation from the central galaxy. The CGM is imprinted by the past, present and future evolution of its central galaxy and environment. The cool atomic and molecular phases are of particular interest as they dominate the mass budget of outflows and provide a reservoir of direct star forming fuel for the galaxy to accrete. In the early universe where accretion rates, mergers, and feedback processes peak, the cycle of gas through the CGM is most vigorous. Sub-mm observations have detected cold gas in extended halos and gas flows around high redshift galaxies but are thus far limited to the most massive, extreme or gravitationally lensed sources, using just a handful of the strongest emission and absorption lines. A significant increase (5−10×) in spectral line sensitivity compared with the current ALMA is needed to push physical scales, densities and properties to a new regime. We present three key scientific cases for an ALMA2040 telescope: (i) direct imaging of extended [CII]-traced CGM halos around Milky-Way-progenitor galaxies at z=4-8; (ii) resolved detection of cold, clumpy outflows on ∼100 pc scales tied to individual star-forming clumps; and (iii) multi-species/-transition emission and absorption diagnostics that jointly constrain the density, chemistry, and radiation fields permeating the cool CGM and its multiphase gas flows.
ER  -