论文标题
证明了对原始重力波的改善限制,并进行了删节
A Demonstration of Improved Constraints on Primordial Gravitational Waves with Delensing
论文作者
论文摘要
We present a constraint on the tensor-to-scalar ratio, $r$, derived from measurements of cosmic microwave background (CMB) polarization $B$-modes with "delensing," whereby the uncertainty on $r$ contributed by the sample variance of the gravitational lensing $B$-modes is reduced by cross-correlating against a lensing $B$-mode template.该模板是通过将极化CMB的估计与投影大规模结构的示踪剂相结合来构建的。所使用的大尺度结构示踪剂是源自普朗克卫星数据的宇宙红外背景的地图,而偏振的CMB图来自南极望远镜,二头肌/凯克和普朗克数据的组合。我们将二头肌/凯克的可能性分析框架扩展到接受镜头模板,并使用与以前的分析相同的参数前景建模将其应用于通过2014年收集的二头肌/凯克数据集。从模拟中,我们发现$ r $的不确定性减少了$ \ sim10 \%$,从$σ(r)$ = 0.024降低到0.022,可以将其与$ \ sim26 \%$减少使用时,使用完美的镜头模板。将技术应用于真实数据,对$ r $的约束从$ r_ {0.05} <0.090 $提高到$ r_ {0.05} <0.082 $(95 \%c.l.)。这是通过删除通过$ r $约束改进的首次演示。
We present a constraint on the tensor-to-scalar ratio, $r$, derived from measurements of cosmic microwave background (CMB) polarization $B$-modes with "delensing," whereby the uncertainty on $r$ contributed by the sample variance of the gravitational lensing $B$-modes is reduced by cross-correlating against a lensing $B$-mode template. This template is constructed by combining an estimate of the polarized CMB with a tracer of the projected large-scale structure. The large-scale-structure tracer used is a map of the cosmic infrared background derived from Planck satellite data, while the polarized CMB map comes from a combination of South Pole Telescope, BICEP/Keck, and Planck data. We expand the BICEP/Keck likelihood analysis framework to accept a lensing template and apply it to the BICEP/Keck data set collected through 2014 using the same parametric foreground modelling as in the previous analysis. From simulations, we find that the uncertainty on $r$ is reduced by $\sim10\%$, from $σ(r)$= 0.024 to 0.022, which can be compared with a $\sim26\%$ reduction obtained when using a perfect lensing template. Applying the technique to the real data, the constraint on $r$ is improved from $r_{0.05} < 0.090$ to $r_{0.05} < 0.082$ (95\% C.L.). This is the first demonstration of improvement in an $r$ constraint through delensing.