New Constraints on the Evolution of the MH i−M Scaling Relation Combining CHILES and MIGHTEE-H i Data
Journal article, 2025

The improved sensitivity of interferometric facilities to the 21 cm line of atomic hydrogen (H i) enables studies of its properties in galaxies beyond the local Universe. In this work, we perform a 21 cm line spectral stacking analysis combining the MeerKAT International GigaHertz Tiered Extragalactic Exploration and COSMOS H i Large Extra-galactic Survey surveys in the COSMOS field to derive a robust H i-stellar mass relation at z ≈ 0.36. In particular, by stacking thousands of star-forming galaxies subdivided into stellar mass bins, we optimize the signal-to-noise ratio of targets and derive mean H i masses in the different stellar mass intervals for the investigated galaxy population. We combine spectra from the two surveys, estimate H i masses, and derive the scaling relation log 10 M H I = ( 0.32 ± 0.04 ) log 10 M ⋆ + ( 6.65 ± 0.36 ) . Our findings indicate that galaxies at z ≈ 0.36 are H i richer than those at z ≈ 0 but H i poorer than those at z ≈ 1, with a slope consistent across redshift, suggesting that stellar mass does not significantly affect H i exchange mechanisms. We also observe a slower growth rate H i relative to the molecular gas, supporting the idea that the accretion of cold gas is slower than the rate of consumption of molecular gas to form stars. This study contributes to understanding the role of atomic gas in galaxy evolution and sets the stage for future development of the field in the upcoming Square Kilometre Array era.

Author

Alessandro Bianchetti

Istituto nazionale di astrofisica (INAF)

University of Padua

Francesco Sinigaglia

University of Geneva

University of Zürich

G. Rodighiero

University of Padua

Istituto nazionale di astrofisica (INAF)

E. C. Elson

University of the Western Cape

M. Vaccari

Istituto di Radioastronomia

University of the Western Cape

D. J. Pisano

University of Cape Town

Nicholas Luber

Columbia University

I. Prandoni

Istituto di Radioastronomia

Kelley Michelle Hess

Chalmers, Space, Earth and Environment, Onsala Space Observatory

Netherlands Institute for Radio Astronomy (ASTRON)

Maarten Baes

Ghent university

E. A.K. Adams

Netherlands Institute for Radio Astronomy (ASTRON)

University of Groningen

F. M. Maccagni

Istituto nazionale di astrofisica (INAF)

Alvio Renzini

Istituto nazionale di astrofisica (INAF)

Laura Bisigello

University of Padua

Istituto nazionale di astrofisica (INAF)

Min Yun

University of Massachusetts

E. Momjian

National Radio Astronomy Observatory

Hansung B. Gim

Montana State University

University of Massachusetts

Hengxing Pan

University of Oxford

T. Oosterloo

National Radio Astronomy Observatory

Netherlands Institute for Radio Astronomy (ASTRON)

Richard Dodson

University of Western Australia

Danielle Lucero

Virginia Polytechnic Institute and State University

B. S. Frank

Royal Observatory

South African Radio Astronomy Observatory (SARAO)

University of the Western Cape

University of Cape Town

O. Ilbert

Laboratoire d'Astrophysique de Marseille

L. J. M. Davies

University of Western Australia

Ali A. Khostovan

Rochester Institute of Technology

M. Salvato

Max Planck Society

Astrophysical Journal

0004-637X (ISSN) 1538-4357 (eISSN)

Vol. 982 2 82

Subject Categories (SSIF 2025)

Astronomy, Astrophysics, and Cosmology

DOI

10.3847/1538-4357/adb1b8

More information

Latest update

8/22/2025