New lessons from the H i size-mass relation of galaxiesWang, J., Koribalski, B. S., Serra, P., van der Hulst, T., Roychowdhury, S., Kamphuis, P. & Chengalur, J. N., 1-Aug-2016, In : Monthly Notices of the Royal Astronomical Society. 460, 2, p. 2143-2151 9 p.
Research output: Contribution to journal › Article › Academic › peer-review
We revisit the H i size-mass relation of galaxies with a sample of more than 500 nearby galaxies covering over five orders of magnitude in H i mass and more than 10 B-band magnitudes. The relation is remarkably tight with a scatter sigma similar to 0.06 dex, or 14 per cent. The scatter does not change as a function of galaxy luminosity, H i richness or morphological type. The relation is linked to the fact that dwarf and spiral galaxies have a homogeneous radial profile of H i surface density in the outer regions when the radius is normalized by D-H i. The early-type disc galaxies typically have shallower H i radial profiles, indicating a different gas accretion history. We argue that the process of atomic-to-molecular gas conversion or star formation cannot explain the tightness of the D-H i-M-H i relation. This simple relation puts strong constraints on simulation models for galaxy formation.
|Number of pages||9|
|Journal||Monthly Notices of the Royal Astronomical Society|
|Publication status||Published - 1-Aug-2016|
- Galaxy: formation, galaxies: ISM, DIGITAL SKY SURVEY, STOCHASTIC STAR-FORMATION, DWARF IRREGULAR GALAXIES, FAST ALPHA SURVEY, COSMIC-RAY GAS, NEARBY GALAXIES, STELLAR MASS, DARK-MATTER, METALLICITY RELATION, INTERSTELLAR-MEDIUM