论文标题
通过21厘米强度映射实验测量暗能量的前景：联合调查策略
Prospects for measuring dark energy with 21 cm intensity mapping experiments: A joint survey strategy
论文作者
论文摘要
21 cm强度映射（IM）技术为我们提供了一种有效的观察宇宙大规模结构（LSS）的方法。从LSS数据中，可以使用重子振荡和红移空间扭曲来追踪宇宙的膨胀和生长历史，从而测量暗能量参数。在本文中，我们通过三个21 cm IM实验的协同作用对宇宙学参数估计进行了预测。具体来说，我们采用了一种新颖的联合调查策略，快速（$ 0 <z <0.35 $）+ska1-mid（$ 0.35 <z <0.8 $）+hirax（$ 0.8 <z <2.5 $），以衡量黑能。我们在假设出色的前景去除的假设下模拟了21厘米IM的观察结果。我们发现，三个实验的协同作用可能对宇宙参数构成非常严格的约束。例如，它提供$σ（ω_ {\ rm m}）= 0.0039 $和$σ（H_0）= 0.27 \ \ rm km km \ s^{ - 1} \ mpc^{ - 1} $在$λ$ CDM模型中。值得注意的是，在限制动态暗能模型时，协同作用可能会破坏宇宙参数归化。具体而言，联合观察在$ W $ CDM型号中提供$σ（w）= 0.019 $，以及$σ（W_0）= 0.085 $和$σ（W_A）= 0.32 $中的$ W_0W_A $ CDM型号。这些结果比CMB+BAO+SN给出的结果更好或等于。另外，当前景拆卸效率相对较低时，该策略仍然表现良好。因此，21厘米IM联合调查策略是有希望的，值得追求。
The 21 cm intensity mapping (IM) technique provides us with an efficient way to observe the cosmic large-scale structure (LSS). From the LSS data, one can use the baryon acoustic oscillation and redshift space distortion to trace the expansion and growth history of the universe, and thus measure the dark energy parameters. In this paper, we make a forecast for cosmological parameter estimation with the synergy of three 21 cm IM experiments. Specifically, we adopt a novel joint survey strategy, FAST ($0<z<0.35$)+SKA1-MID ($0.35<z<0.8$)+HIRAX ($0.8<z<2.5$), to measure dark energy. We simulate the 21 cm IM observations under the assumption of excellent foreground removal. We find that the synergy of three experiments could place quite tight constraints on cosmological parameters. For example, it provides $σ(Ω_{\rm m})=0.0039$ and $σ(H_0)=0.27\ \rm km\ s^{-1}\ Mpc^{-1}$ in the $Λ$CDM model. Notably, the synergy could break the cosmological parameter degeneracies when constraining the dynamical dark energy models. Concretely, the joint observation offers $σ(w)=0.019$ in the $w$CDM model, and $σ(w_0)=0.085$ and $σ(w_a)=0.32$ in the $w_0w_a$CDM model. These results are better than or equal to those given by CMB+BAO+SN. In addition, when the foreground removal efficiency is relatively low, the strategy still performs well. Therefore, the 21 cm IM joint survey strategy is promising and worth pursuing.
