论文标题
在差异模拟中有偏见的示踪剂的统计数据
Statistics of biased tracers in variance-suppressed simulations
论文作者
论文摘要
宇宙学模拟在分析观察到的宇宙大规模结构中起着越来越重要的作用。最近，它们在建立混合模型中特别重要，该混合模型将扰动偏置扩展与从N体模拟中提取的位移场相结合，以描述偏置示踪剂的聚类。在这里，我们表明，采用称为“固定和配对”（F＆P）的技术可以显着提高此类混合模型的统计精度。具体而言，通过数值和分析方式，我们表明F＆P模拟为混合模型所采用的所有统计数据提供了无偏的估计，同时降低了多达两个数量级，它们在大尺度上的不确定性。这大致意味着可以使用2GPC A侧的模拟来分析类似欧几里得的调查 - 占调查量的20％。我们的工作确立了用于银河系聚类的当前混合理论模型的F＆P的鲁棒性，这是实现大规模结构测量最佳利用的重要一步。
Cosmological simulations play an increasingly important role in analysing the observed large-scale structure of the Universe. Recently, they have been particularly important in building hybrid models that combine a perturbative bias expansion with displacement fields extracted from N-body simulations to describe the clustering of biased tracers. Here, we show that simulations that employ a technique referred to as "Fixing-and-pairing" (F&P) can dramatically improve the statistical precision of such hybrid models. Specifically, by numerical and analytic means, we show that F&P simulations provide unbiased estimates for all statistics employed by hybrid models while reducing, by up to two orders of magnitude, their uncertainty on large scales. This roughly implies that an EUCLID-like survey could be analysed using simulations of 2Gpc a side -- a 20% of the survey volume. Our work establishes the robustness of F&P for current hybrid theoretical models for galaxy clustering, an important step towards achieving an optimal exploitation of large-scale structure measurements.
