Villaescusa-Navarro, FranciscoFranciscoVillaescusa-NavarroBULL, PHILIPPHILIPBULLVIEL, MATTEOMATTEOVIEL2020-03-232020-03-2320150004-637Xhttp://hdl.handle.net/20.500.12386/23480We investigate the signatures left by massive neutrinos on the spatial distribution of neutral hydrogen (H i) in the post-reionization era by running hydrodynamic simulations that include massive neutrinos as additional collisionless particles. We find that halos in massive/massless neutrino cosmologies host a similar amount of neutral hydrogen, although for a fixed halo mass, on average, the H i mass increases with the sum of the neutrino masses. Our results show that H i is more strongly clustered in cosmologies with massive neutrinos, while its abundance, Ω<SUB>H i</SUB>(z), is lower. These effects arise mainly from the impact of massive neutrinos on cosmology: they suppress both the amplitude of the matter power spectrum on small scales and the abundance of dark matter halos. Modeling the H i distribution with hydrodynamic simulations at z > 3 and a simple analytic model at z < 3, we use the Fisher matrix formalism to conservatively forecast the constraints that Phase 1 of the Square Kilometre Array will place on the sum of neutrino masses, M<SUB>ν</SUB> ≡ Σ m<SUB>ν</SUB>. We find that with 10,000 hr of interferometric observations at 3 ≲ z ≲ 6 from a deep and narrow survey with SKA1-LOW, the sum of the neutrino masses can be measured with an error σ(M<SUB>ν</SUB>) ≲ 0.3 eV (95% CL). Similar constraints can be obtained with a wide and deep SKA1-MID survey at z ≲ 3, using the single-dish mode. By combining data from MID, LOW, and Planck, plus priors on cosmological parameters from a Stage IV spectroscopic galaxy survey, the sum of the neutrino masses can be determined with an error σ(M<SUB>ν</SUB>) ≃ 0.06 eV (95% CL).STAMPAenArticle10.1088/0004-637X/814/2/1462-s2.0-84948769311000371463200015https://iopscience.iop.org/article/10.1088/0004-637X/814/2/1462015ApJ...814..146VFIS/05 - ASTRONOMIA E ASTROFISICAScienze Fisiche Settori ERC (ERC) di riferimento::PE2 Fundamental constituents of matter: particle, nuclear, plasma, atomic, molecular, gas, and optical plasma