论文标题
通货膨胀波动的深色辐射
Dark Radiation from Inflationary Fluctuations
论文作者
论文摘要
轻便的新载体玻色子可以通过通货膨胀期间的量子波动产生重力。如果这些粒子巧妙地耦合并且在宇宙学上可以稳定，则可以解释观察到的暗物质丰度。但是，在最小的无异常$ u（1）$扩展到标准模型中，如果至少一个中微子质量特征态足够轻，这些向量通常会腐烂到中微子。如果这些衰减发生在中微子解耦和CMB冻结之间，则在可以改善哈勃张力的水平下，产生的辐射能密度可以促进$Δn_{\ rm eff} $，并可以通过未来的CMB和Relic Neutrino检测实验发现。由于BBN之后从向量衰减产生了其他中微子，因此此情况预测重组时$Δn_ {\ rm eff}> 0 $，但是$Δn_{\ rm eff} = 0 $ bbn期间。此外，由于取消了偶然的取消，对$Δn_ {\ rm eff} $的贡献大致独立于质量。
Light new vector bosons can be produced gravitationally through quantum fluctuations during inflation; if these particles are feebly coupled and cosmologically metastable, they can account for the observed dark matter abundance. However, in minimal anomaly free $U(1)$ extensions to the Standard Model, these vectors generically decay to neutrinos if at least one neutrino mass eigenstate is sufficiently light. If these decays occur between neutrino decoupling and CMB freeze out, the resulting radiation energy density can contribute to $ΔN_{\rm eff}$ at levels that can ameliorate the Hubble tension and be discovered with future CMB and relic neutrino detection experiments. Since the additional neutrinos are produced from vector decays after BBN, this scenario predicts $ΔN_{\rm eff} > 0$ at recombination, but $ΔN_{\rm eff} = 0$ during BBN. Furthermore, due to a fortuitous cancellation, the contribution to $ΔN_{\rm eff}$ is approximately mass independent.
