The ALMA-CRISTAL Survey: Weak Evidence for Star-formation-driven Outflows in z ∼ 5 Main-sequence Galaxies
Journal article, 2025
There is a broad consensus from theory that stellar feedback in galaxies at high redshifts is essential to their evolution, alongside conflicting evidence in the observational literature about its prevalence and efficacy. To this end, we utilize deep, high-resolution [C II] emission-line data taken as part of the [C II] resolved interstellar medium (ISM) in star-forming galaxies with the Atacama Large Millimeter/submillimeter Array (CRISTAL) survey. Excluding sources with kinematic evidence for gravitational interactions, we perform a rigorous stacking analysis of the remaining 15 galaxies to search for broad emission features that are too weak to detect in the individual spectra, finding only weak evidence that a broad component is needed to explain the composite spectrum. Additionally, such evidence is mostly driven by CRISTAL-02, which is already known to exhibit strong outflows in multiple ISM phases. Interpreting modest residuals in the stack at v ∼ 300 km s−1 as an outflow, we derive a mass outflow rate of M ̇ out = 26 ± 11 M⊙ yr−1 and a cold outflow mass-loading factor of ηm = 0.49 ± 0.20. This result holds for the subsample with the highest star formation rate surface density (ΣSFR > 1.93 M⊙ yr−1 kpc−2), but no such broad component is present in the composite of the lower-star-formation-rate density subsample. Our results imply that the process of star-formation-driven feedback may already be in place in typical galaxies at z = 5, but on average are not strong enough to completely quench ongoing star formation.
Author
Jack E. Birkin
Texas A&M University
Justin Spilker
Texas A&M University
R. Herrera-Camus
University of Concepcion
Rebecca L. Davies
Swinburne University of Technology
ARC Centre of Excellence for All-sky Astrophysics
Lilian L. Lee
Max Planck Society
Manuel Aravena
Diego Portales University
Millenium Nucleus for Galaxies (MINGAL)
Roberto Assef
Diego Portales University
Loreto Barcos-Munoz
National Radio Astronomy Observatory
University of Virginia
A. Bolatto
University of Maryland
T. Diaz-Santos
European University Cyprus
Foundation for Research and Technology-Hellas (FORTH)
A. Faisst
California Institute of Technology (Caltech)
Andrea Ferrara
Scuola Normale Superiore di Pisa
Deanne B. Fisher
Swinburne University of Technology
ARC Centre of Excellence for All-sky Astrophysics
J. González-López
Las Campanas Observatory
Pontificia Universidad Catolica de Chile
Ryota Ikeda
The Graduate University for Advanced Studies (SOKENDAI)
National Astronomical Observatory of Japan
Kirsten Knudsen
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Juno Li
University of Western Australia
Yuan Li
Texas A&M University
I. De Looze
Ghent university
D. Lutz
Max Planck Society
Ikki Mitsuhashi
National Astronomical Observatory of Japan
University of Tokyo
Ana Posses
Texas A&M University
M. Relano
Universidad de Granada
Manuel Solimano
Diego Portales University
Ken Ichi Tadaki
Hokkai Gakuen University
National Astronomical Observatory of Japan
Vicente Villanueva
University of Concepcion
Astrophysical Journal
0004-637X (ISSN) 1538-4357 (eISSN)
Vol. 985 2 243Subject Categories (SSIF 2025)
Atom and Molecular Physics and Optics
Astronomy, Astrophysics, and Cosmology
DOI
10.3847/1538-4357/adced3