论文标题
大爆炸核合成限制对宇宙的无菌中微子和Lepton不对称
Big Bang Nucleosynthesis constraints on sterile neutrino and lepton asymmetry of the Universe
论文作者
论文摘要
我们考虑无菌中微子的宇宙学影响，质量为$ 150-450 $ MEV。无菌中微子的衰减改变了宇宙的热历史，并影响重组时辐射的能量密度和大爆炸核合成（BBN）结果。我们从氦4和氘的原始丰度中获得了无菌中微子参数的严重限制。我们还发现，在特定模型中，可以通过假设活跃中微子中的大量轻子不对称来大大放松约束。在这种情况下，一致的参数会导致$ n _ {\ mathrm {eff}} \ simeq 3.2-3.4 $，并可以减轻哈勃张力。
We consider the cosmological effects of sterile neutrinos with the masses of $150- 450$ MeV. The decay of sterile neutrinos changes the thermal history of the Universe and affects the energy density of radiation at the recombination and the big bang nucleosynthesis (BBN) results. We derive severe constraints on the parameters of sterile neutrinos from the primordial abundances of helium-4 and deuterium. We also find that in a particular model the constraints can be considerably relaxed by assuming a large lepton asymmetry in the active neutrinos. In this case, the consistent parameters result in $N_{\mathrm{eff}} \simeq 3.2- 3.4$ and can alleviate the Hubble tension.
