Exploring the [CII] and the dust continuum with the ALPINE survey: first scientific results

ALPINE is an ALMA large program, which aims to build a first comprehensive picture of the obscured star formation and the properties of the interstellar medium in normal star-forming galaxies at the end of reionization. We targeted the [CII] line together with the 158-micron dust continuum in a sample of 122 4<z<6 normal star forming galaxies from optical spectroscopic sample. During the spring and summer 2015, 102 of our objects has been observed. At the abstract submission deadline (Feb 2018), we reduced all these data, built a first [CII] and continuum catalog, obtained first preliminary science result. The first science papers should thus be submitted or at least well advanced before the conference. The individual continuum detections at z>4 are still rare and our new sample allow us to address if some obscured star formation is missed by dust-corrected UV estimates and in particular if the famous IRX-beta relation is valid at z>4. With our data, we can also put first far-infrared constraints on the SFR-Mstar relation and the obscured star formation density at z>4. We detected [CII] with ~70% success rate. A possible [CII]-deficit at high redshift has been recently discussed because of the low-metallicity, the high interstellar radiation field, and the high CMB temperature. I will present our new measurement of the SFR-L[CII] relation on this first z>4 statistical sample. Finally, I will present our new constraints on the [CII] luminosity function. Finally, thanks to its depth and the its large number of non-contiguous pointing, ALPINE provides for free deep survey of galaxies at z<4, which is much less affected by cosmic variance than usual observations. I will present the properties of these serendipitous continuum and line detections. I will show our new measurements of the deep continuum number counts, the dust luminosity function at z~2.5, and the high-J CO luminosity function at z<2.