A³COSMOS: the dust mass function and dust mass density at $0.5<z<6$

Context. Although dust in galaxies represents only a few percent of the total baryonic mass, it plays a crucial role in the physical processes occurring in galaxies. Studying the dust content of galaxies, particularly at high$-z$, is therefore crucial to understand the link between dust production, obscured star formation and the build-up of galaxy stellar mass. Aims. To study the dust properties (mass and temperature) of the largest Atacama Large Millimeter/submillimeter Array (ALMA)-selected sample of star-forming galaxies available from the archive (A³COSMOS) and derive the dust mass function and dust mass density of galaxies from $z=0.5\,-\,6$. Methods. We performed spectral energy distribution (SED) fitting with the CIGALE code to constrain the dust mass and temperature of the A³COSMOS galaxy sample, thanks to the UV-to-near-infrared photometric coverage of each galaxies combined with the ALMA (and Herschel when available) coverage of the Rayleigh-Jeans tail of their dust-continuum emission. We then computed and fitted the dust mass function by combining the A³COSMOS and state-of-the-art { Herschel} samples, in order to obtain the best estimate of the integrated dust mass density up to z ~ 6. Results. Galaxies in 3 have dust masses between ~ 10⁸ and ~ 109.5 M_. From the SED fitting, we were also able to derive a dust temperature, finding that the distribution of the dust temperature peaks at ~ 30-35K. The dust mass function at $z=0.5\,-\,6$ evolves with an increase of M^* and decrease of the number density (Φ ^*) and is in good agreement with literature estimates. The dust mass density shows a smooth decrease in its evolution from z ~ 0.5 to z ~ 6, which is steeper than what is found by models at z 2.