Skip to Main content Skip to Navigation
Journal articles

The contribution of starbursts and normal galaxies to infrared luminosity functions at z < 2

Abstract : We present a parameter-less approach to predict the shape of the infrared (IR) luminosity function (LF) at redshifts $z \leq$ 2. It requires no tuning and relies on only three observables: (1) the redshift evolution of the stellar mass function for star-forming galaxies, (2) the evolution of the specific star formation rate (sSFR) of main-sequence galaxies, and (3) the double-Gaussian decomposition of the sSFR-distribution at fixed stellar mass into a contribution (assumed redshift- and mass-invariant) from main-sequence and starburst activity. This self-consistent and simple framework provides a powerful tool for predicting cosmological observables: observed IR LFs are successfully matched at all $z \leq$ 2, suggesting a constant or only weakly redshift-dependent contribution (8-14%) of starbursts to the star formation rate density. We separate the contributions of main-sequence and starburst activity to the global IR LF at all redshifts. The luminosity threshold above which the starburst component dominates the IR LF rises from log($L_{IR}$/$L_ \odot$) = 11.4 to 12.8 over 0 < z < 2, reflecting our assumed (1$+z)^{2.8}$-evolution of sSFR in main-sequence galaxies.
Complete list of metadata
Contributor : Bruno Savelli <>
Submitted on : Wednesday, January 6, 2021 - 2:39:15 PM
Last modification on : Friday, January 8, 2021 - 3:27:14 AM
Long-term archiving on: : Wednesday, April 7, 2021 - 8:18:18 PM


Files produced by the author(s)




Mark T. Sargent, M. Béthermin, Emanuele Daddi, D. Elbaz. The contribution of starbursts and normal galaxies to infrared luminosity functions at z < 2. The Astrophysical journal letters, Bristol : IOP Publishing, 2012, 747 (2), pp.L31. ⟨10.1088/2041-8205/747/2/L31⟩. ⟨cea-00995654⟩



Record views


Files downloads