Planck约束与多场暴胀作为种子的原初黑洞暗物质引力波预言
Planck Constraints and Gravitational Wave Forecasts for Primordial Black Hole Dark Matter Seeded by Multifield Inflation
AI总结：
本文对与引力非最小耦合的多场暴胀模型进行MCMC分析，结合Planck 2018数据约束参数，发现谱指数$n_s$主导约束且存在简并方向可避免高度微调，并预测该参数区域可在未来实验中产生可观测的引力波信号。
摘要：
我们对一个简单而通用的多场暴胀模型进行了马尔可夫链蒙特卡罗（MCMC）分析，该模型由两个相互耦合且与引力非最小耦合的标量场表征，并拟合至Planck 2018宇宙微波背景（CMB）数据。具体而言，模型参数受到CMB尺度上的标量曲率扰动原初功率谱振幅$A_s$、谱指数$n_s$以及张量与标量模式功率比$r$的数据约束，先验条件为该原初功率谱还应产生足以解释观测到的暗物质（DM）丰度的原初黑洞（PBH）。我们发现，特别是$n_s$控制了对我们模型的约束。以往关于暴胀超慢滚阶段形成PBH的研究强调至少一个模型参数需要高度微调，而我们识别出参数空间中的一个简并方向，使得一个参数约$10\%$的偏移可以通过其他参数的相应偏移来补偿，同时保持模型预测与观测之间的紧密拟合。此外，我们发现该允许参数区域在即将开展的实验预计敏感的频段内产生可观测的引力波（GW）信号，包括Advanced LIGO和Virgo、Einstein Telescope（ET）、Cosmic Explorer（CE）、DECIGO和LISA。
英文摘要：
We perform a Markov Chain Monte Carlo (MCMC) analysis of a simple yet generic multifield inflation model characterized by two scalar fields coupled to each other and nonminimally coupled to gravity, fit to Planck 2018 cosmic microwave background (CMB) data. In particular, model parameters are constrained by data on the amplitude of the primordial power spectrum of scalar curvature perturbations on CMB scales $A_s$, the spectral index $n_s$, and the ratio of power in tensor to scalar modes $r$, with a prior that the primordial power spectrum should also lead to primordial black hole (PBH) production sufficient to account for the observed dark matter (DM) abundance. We find that $n_s$ in particular controls the constraints on our model. Whereas previous studies of PBH formation from an ultra-slow-roll phase of inflation have highlighted the need for at least one model parameter to be highly fine-tuned, we identify a degeneracy direction in parameter space such that shifts by $\sim 10\%$ of one parameter can be compensated by comparable shifts in other parameters while preserving a close fit between model predictions and observations. Furthermore, we find this allowed parameter region produces observable gravitational wave (GW) signals in the frequency ranges to which upcoming experiments are projected to be sensitive, including Advanced LIGO and Virgo, the Einstein Telescope (ET), Cosmic Explorer (CE), DECIGO, and LISA.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
