Probing massive neutrinos with the Minkowski functionals of large-scale structure

Abstract

Abstract Massive neutrinos suppress the growth of structure under their free-streaming scales. The effect is most prominent on small scales where the widely-used two-point statistics can no longer capture the full information. In this work, we study the signatures massive neutrinos leave on large-scale structure (LSS) as revealed by its morphological properties, which are fully described by 4 Minkowski functionals (MFs), and quantify the constraints on the summed neutrino mass Mν from the MFs, by using publicly available N-body simulations. We find the MFs provide important complementary information, and give tighter constraints on Mν than the power spectrum. Specifically, depending on whether massive neutrinos are included in the density field (the 'm' field) or not (the 'cb' field), we find the constraint on Mν from the MFs with a smoothing scale of RG = 5h -1Mpc is 48 or 4 times better than that from the power spectrum. When the MFs are combined with the power spectrum, they can improve the constraint on Mν from the latter by a factor of 63 for the 'm' field and 5 for the 'cb' field. Notably, when the 'm' field is used, the constraint on Mν from the MFs can reach 0.0177eV with a volume of 1( -1Gpc)3, while the combination of the MFs and power spectrum can tighten this constraint to be 0.0133eV, a 4.5σ significance on detecting the minimum sum of the neutrino masses. For the 'm' field, we also find the σ 8 and Mν degeneracy is broken with the MFs, leading to stronger constraints on all 6 cosmological parameters considered in this work than the power spectrum.