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.

Cosmic voids are large underdense regions that, together with galaxy clusters, filaments and walls, build up the large-scale structure of the Universe. The void size function provides a powerful probe to test the cosmological framework. However, to fully exploit this statistics, the void sample has to be properly cleaned from spurious objects. Furthermore, the bias of the mass tracers used to detect these regions has to be taken into account in the size function model. In our work we test a cleaning algorithm and a new void size function model on a set of simulated dark matter halo catalogues, with different mass and redshift selections, to investigate the statistics of voids identified in a biased mass density field. We then investigate how the density field tracers' bias affects the detected size of voids. The main result of this analysis is a new model of the size function, parameterised in terms of the linear effective bias of the tracers used, which is straightforwardly inferred from the large-scale two-point correlation function. This method is a crucial step in exploiting real surveys. The proposed size function model has been accurately calibrated on halo catalogues, and used to validate the possibility to provide forecasts on the cosmological constraints, namely on the matter density contrast, Ω M , and on the normalisation of the linear matter power spectrum, σ 8 , at different redshifts.