论文标题
中微子自我相互作用对弱解耦和大爆炸核合成的后果
Consequences of neutrino self interactions for weak decoupling and big bang nucleosynthesis
论文作者
论文摘要
我们计算和讨论中微子自我互动对早期宇宙中弱脱钩和大爆炸核合成（BBN）物理的影响。在标准模型的这种中微子扇区扩展中，中微子可能不会自由流，但可以保持热耦合。然而，仅通过普通的弱相互作用，中微子将能量和熵与早期宇宙的光子，电子 - 旋律和重子分量交换。我们检查了中微子自我交织对原始氦和氘丰度的影响以及$ n _ {\ rm eff} $，这是光子去耦时相对论能量密度的量度。这些量在弱解耦时期的物理学中确定或可能受到物理的影响。已调用自我相互作用的中微子来解决许多异常，包括作为减轻哈勃参数张力的可能手段。我们的计算表明，其中一些中微子自我交互方案伴随着BBN的出人意料的细微变化。这样的微小信号需要高精度测量值，这使氘成为此处探索的模型中BBN约束的最佳丰度。
We calculate and discuss the implications of neutrino self-interactions for the physics of weak decoupling and big bang nucleosynthesis (BBN) in the early universe. In such neutrino-sector extensions of the standard model, neutrinos may not free-stream, yet can stay thermally coupled to one another. Nevertheless, the neutrinos exchange energy and entropy with the photon, electron-positron, and baryon component of the early universe only through the ordinary weak interaction. We examine the effects of neutrino self-interaction for the primordial helium and deuterium abundances and $N_{\rm eff}$, a measure of relativistic energy density at photon decoupling. These quantities are determined in, or may be influenced by, the physics in the weak decoupling epoch. Self interacting neutrinos have been invoked to address a number of anomalies, including as a possible means of ameliorating tension in the Hubble parameter. Our calculations show that surprisingly subtle changes in BBN accompany some of these neutrino self-interaction schemes. Such minute signals require high-precision measurements, making deuterium the best abundance for BBN constraints in the models explored here.
