We present a panchromatic study of 11 (sub-)millimetre selected DSFGs with spectroscopically confirmed redshift (1.5 < zspec < 3) in the GOODS-S field, with the aim of constraining their astrophysical properties (e.g. age, stellar mass, dust and gas content) and characterizing their role in the context of galaxy evolution. The multi-wavelength coverage of GOODS-S, from X-rays to radio band, allow us to model galaxy SED by using CIGALE with a novel approach, based on a physical motivated modelling of stellar light attenuation by dust. Median stellar mass (≃ 6.5 × 1010 M⊙) and SFR (≃ 241 M⊙ yr−1) are consistent with galaxy main-sequence at z ∼ 2. The galaxies are experiencing an intense and dusty burst of star formation (median LIR ≃ 2 × 1012 L⊙), with a median age of 750 Myr. The high median content of interstellar dust (Mdust ≃ 5 × 108 M⊙) suggests a rapid enrichment of the ISM (on timescales ∼108 yr). We derived galaxy total and molecular gas content from CO spectroscopy and/or Rayleigh-Jeans dust continuum (1010 ≲ Mgas/M⊙ ≲ 1011), depleted over a typical timescale τdepl ∼ 200 Myr. X-ray and radio luminosities (LX = 1042 − 1044 erg s−1, L1.5 GHz = 1030 − 1031 erg s−1, L6 GHz = 1029 − 1030 erg s−1) suggest that most of the galaxies hosts an accreting radio silent/quiet SMBH. This evidence, along with their compact multi-wavelength sizes (median rALMA ∼ rVLA = 1.8 kpc, rHST = 2.3 kpc) measured from high-resolution imaging (θres ≲ 1 arcsec), indicates these objects as the high-z star-forming counterparts of massive quiescent galaxies, as predicted e.g. by the in-situ scenario. Four objects show some signatures of a forthcoming/ongoing AGN feedback, that is thought to trigger the morphological transition from star-forming disks to ETGs.

In this paper, we study the impact of different galaxy statistics and empirical metallicity scaling relations on the merging rates and properties of compact object binaries. Firstly, we analyze the similarities and differences of using the star formation rate functions versus stellar mass functions as galaxy statistics for the computation of cosmic star formation rate density. We then investigate the effects of adopting the Fundamental Metallicity Relation versus a classic Mass Metallicity Relation to assign metallicity to galaxies with given properties. We find that when the Fundamental Metallicity Relation is exploited, the bulk of the star formation occurs at relatively high metallicities, even at high redshift; the opposite holds when the Mass Metallicity Relation is employed, since in this case the metallicity at which most of the star formation takes place strongly decreases with redshift. We discuss the various reasons and possible biases giving rise to this discrepancy. Finally, we show the impact of these different astrophysical prescriptions on the merging rates and properties of compact object binaries; specifically, we present results for the redshift-dependent merging rates and for the chirp mass and time delay distributions of the merging binaries.

We have obtained three-dimensional maps of the universe in ∼ 200×200×80 comoving Mpc 3 (cMpc 3 ) volumes each at z = 5.7 and 6.6 based on a spectroscopic sample of 179 galaxies that achieves 80% completeness down to the Lyα luminosity of log(L Lyα /[erg s −1 ]) = 43.0, based on our Keck and Gemini observations and the literature. The maps reveal filamentary large-scale structures and two remarkable overdensities made out of at least 44 and 12 galaxies at z = 5.692 (z57OD) and z = 6.585 (z66OD), respectively, making z66OD the most distant overdensity spectroscopically confirmed to date with > 10 spectroscopically confirmed galaxies. We compare spatial distributions of submillimeter galaxies at z 4 − 6 with our z = 5.7 galaxies forming the large-scale structures, and detect a 99.97% signal of cross correlation, indicative of a clear coincidence of dusty star-forming galaxy and dust unobscured galaxy formation at this early epoch. The galaxies in z57OD and z66OD are actively forming stars with star formation rates (SFRs) 5 times higher than the main sequence, and particularly the SFR density in z57OD is 10 times higher than the cosmic average at the redshift (a.k.a. the Madau-Lilly plot). Comparisons with numerical simulations suggest that z57OD and z66OD are protoclusters that are progenitors of the present-day clusters with halo masses of ∼ 10 14 M .