NOEMA formIng Cluster survEy COSMOS field

We find that the radial stellar mass densities of the eight groups are consistent with a NFW profile, supporting the idea that they are collapsed structures hosted by a single dark matter halo. The best halo mass estimates are log(Mh/M_{sun}_)=12.8-13.7 with a general uncertainty of 0.3dex. Based on the halo mass estimates, we derived baryonic accretion rates (BARs) of (1-8)x10^3^M_{sun}_/yr for this sample.

Together with massive groups in the literature, we find a quasi-linear correlation between the integrated SFR/BAR ratio and the theoretical halo mass limit for cold streams, Mstream/Mh, with SFR/BAR=10^(-0.46+/-0.22)^(Mstream/Mh)^(0.71+/-0.16)^ with a scatter of 0.40dex. Furthermore, we compared the halo masses and the stellar masses with simulations, and find that the halo masses of all structures are consistent with those of progenitors of Mh(z=0)>10^14^M_{sun}_ galaxy clusters, and that the most massive central galaxies have stellar masses consistent with those of the brightest cluster galaxy progenitors in the TNG300 simulation.

Above all, the results strongly suggest that these massive structures are in the process of forming massive galaxy clusters via baryonic and dark matter accretion.