Abstract
We present the detailed characterisation of a sample of 56 sources
serendipitously detected in ALMA Band-7, as part of the ALMA Large Program to
INvestigate CII at Early Times (ALPINE) in COSMOS and ECDFS. These sources have
been used to derive the total infrared luminosity function (LF) and to estimate
the cosmic star formation rate density (SFRD) up to z=6. We have looked for
counterparts in all the available multi-wavelength and photometric redshift
catalogues, and in deeper near- and mid-IR source lists and maps, to identify
optically dark sources with no matches in the public catalogues. Our ALMA blind
survey allows us to push further the study of the nature and evolution of dusty
galaxies at high-z, identifying luminous and massive sources to redshifts and
faint luminosities never probed before by any far-infrared surveys. The ALPINE
data are the first ones to sample the faint-end of the infrared LF, showing
little evolution from z=2.5 to z=6, and a flat slope up to the highest
redshifts. The SFRD obtained by integrating the luminosity function remains
almost constant between z=2 and 6, and significantly higher than the optical/UV
derivations, showing an important contribution of dusty galaxies and obscured
star formation up to high-z. About 16. per cent of the ALPINE serendipitous
continuum sources are optically+near-IR dark (7 show a counterpart only in the
mid-IR and no HST or near-IR identification, while 2 are detected as CII
emitters at z=5). The 7 HST and near-IR dark galaxies with mid-IR counterpart
contribute for about 15 per cent of the total SFRD at z=5 and dominate the
high-mass end of the stellar mass function at z>3.
Users
Please
log in to take part in the discussion (add own reviews or comments).