论文标题
带有21厘米强度场的Alcock Paczynski测试
The Alcock Paczynski test with 21cm intensity field
论文作者
论文摘要
提出了在21厘米线强度场中堆叠空隙来通过将空隙堆叠来的可行性。我们分析了Illstris-TNG模拟以获得21cm信号图。然后，我们根据21cm强度字段随机分发粒子，以使用公开可用的代码，VIDE查找空隙。就像在星系聚类中一样，由于它在真实空间上变成球形，但由于奇特的速度在红移空间中的特殊速度而沿着视线沿着视线挤压。堆叠的void的红移空间失真弱取决于红移，我们表明，线性预测可以很好地描述依赖性，而偏移量的幅度为自由参数。我们发现使用21厘米强度图中使用堆叠的空隙的AP测试是可行的，并且对$ω_ {\ rm m} $和$ w $的参数估计是无偏见的。
Feasibility of the Alcock Paczynski (AP) test by stacking voids in the 21cm line intensity field is presented. We analyze the Illstris-TNG simulation to obtain the 21cm signal map. We then randomly distribute particles depending on the 21cm intensity field to find voids by using publicly available code, VIDE. As in the galaxy clustering, the shape of the stacked void in the 21cm field is squashed along the line of sight due to the peculiar velocities in redshift-space, although it becomes spherical in real-space. The redshift-space distortion for the stacked void weakly depends on redshift and we show that the dependency can be well described by the linear prediction, with the amplitude of the offset being free parameters. We find that the AP test using the stacked voids in a 21cm intensity map is feasible and the parameter estimation on $Ω_{\rm m}$ and $w$ is unbiased.
