Possible evidences for cosmological massive neutrinos

Abstract

Abstract A key question in cosmology is whether massive neutrinos exist on cosmic scales. Current cosmological observations have severely compressed the viable range for neutrino masses and even prefer phenomenologically an effective negative mass. This poses a great challenge to the cosmological search for neutrinos. Based on current background and large scale structure data, taking a full red-shift and/or scale tomography method, we obtain one beyond $$5\,\sigma$$ 5 σ , two $$3\,\sigma$$ 3 σ , and two $$2\,\sigma$$ 2 σ evidences of massive neutrinos, spanning both high and low red-shifts, as well as both small and intermediate scales. Specifically, for the case of red-shift tomography, we find the neutrino mass sum $$\Sigma m_\nu ^{1}=1.01^{+0.47}_{-0.58}$$ Σ m ν 1 = 1 . 01 - 0.58 + 0.47 eV in $$z \in [0, 1]$$ z ∈ [ 0 , 1 ] using the data combination of CMB, BAO, and supernova, indicating a $$2\,\sigma$$ 2 σ clue of nonzero neutrino mass, while the addition of WiggleZ galaxy power spectrum leads to $$\Sigma m_\nu ^{1}=0.65\pm 0.25$$ Σ m ν 1 = 0.65 ± 0.25 eV, implying a $$3\,\sigma$$ 3 σ evidence of massive neutrinos. For the case of scale tomography, we give $$\Sigma m_\nu ^{k1}=0.75^{+0.20}_{-0.27}$$ Σ m ν k 1 = 0 . 75 - 0.27 + 0.20 eV in $$k \in [10^{-1}, +\infty )$$ k ∈ [ 10 - 1 , + ∞ ) h Mpc $$^{-1}$$