English

ALMA CO-CAVITY I. Resolved Molecular Gas in Void Galaxies

Astrophysics of Galaxies 2026-05-25 v1

Abstract

The environment plays a key role in galaxy evolution, yet it remains unclear how detailed molecular gas properties and their connection to star formation and stellar content are influenced by both large-scale and local environments. Here we introduce the ALMA CO-CAVITY project, the first interferometric CO(1-0) survey of a large sample of 41 void galaxies (VGs) to characterise in detail their molecular gas properties. It is built over the CAVITY project, offering optical integral field unit (IFU) data, enabling a direct, pixel-to-pixel comparison between molecular gas (from ALMA), star formation, and stellar properties, as well as the derivation of their scaling relations. In this work we present ALMA data products for our sample, containing data cubes, moment maps and position-velocity diagrams at angular resolutions of 1 arcsec. We also present molecular gas, stellar mass, and star formation rate surface density maps at a common resolution of 2.5 arcsec. We contextualise our sample against representative unresolved and resolved surveys. While our sample provides a good representation of the VG population and follows the distribution of key properties seen in star-forming galaxy samples, galaxies included in resolved studies from the literature tend to be more massive, less isolated, and located in denser large-scale environments. We present global scaling relations for the ALMA CO-CAVITY sample and find that the molecular gas main sequence exhibits the smallest scatter (0.21 dex), followed by the Schmidt-Kennicutt relation and the star-forming main sequence. From integrated properties alone, we find that these scaling relations for VGs are compatible with those for denser environments. This paper lays the foundation for forthcoming studies exploiting this unique dataset.

Keywords

Cite

@article{arxiv.2605.23399,
  title  = {ALMA CO-CAVITY I. Resolved Molecular Gas in Void Galaxies},
  author = {D. Espada and S. B. De Daniloff and S. Duarte Puertas and M. Argudo-Fernández and U. Lisenfeld and S. Verley and I. Pérez and M. I. Rodríguez and T. Ruiz-Lara and R. García-Benito and L. Sánchez-Menguiano and M. Sánchez-Portal and A. Bongiovanni and S. F. Sánchez and A. Jiménez and R. E. Miura and G. Torres-Ríos and P. Villalba-González and Y. K. González-Koda and B. Bidaran and M. Alcázar-Laynez and A. Zurita and E. Florido and P. Vásquez-Bustos},
  journal= {arXiv preprint arXiv:2605.23399},
  year   = {2026}
}

Comments

20 pages, 12 figures. Accepted for publication in A&A