论文标题
H I和CO线强度图之间的反对称互相关，作为宇宙电动的新探针
Antisymmetric Cross-correlation between H I and CO Line Intensity Maps as a New Probe of Cosmic Reionization
论文作者
论文摘要
H I 21 cm线和CO 2.61 mm线的强度映射从电离时期出现为强大的，互补的探针。但是，地图及其互相关都以前景为主。我们提出了一个新的分析，通过该分析，信号是由前景公正的，即可以在没有前景缓解的情况下对其进行测量。我们在H I 21 cm线的强度图和CO 2.61 mM线之间构建了两点互相关的反对称部分，这是因为两个磁场的统计波动在时间上具有不同的演变。我们表明，这种新信号的迹象可以独立地区分模型，而内而外是否发生在某个时间间隔内。更重要的是，在回归的框架内，我们证明了H I-CO跨功率频谱的偶极子的斜率在大规模上是线性的，与氢的全球中性中性分数的变化速率独立于重新离子化参数，直到倾斜度均取得了趋势，但这种趋势可能依赖于重复的模型，以重复进行依赖框架。 H I-CO偶极子可能是用于电离速度的吸烟枪探针，也可能是用于宇宙电离的“标准速度表”。对该新信号的观察将揭示从中点到临近电离的全球电离历史。
Intensity mapping of the H I 21 cm line and the CO 2.61 mm line from the epoch of reionization has emerged as powerful, complementary, probes of the high-redshift Universe. However, both maps and their cross-correlation are dominated by foregrounds. We propose a new analysis by which the signal is unbiased by foregrounds, i.e. it can be measured without foreground mitigation. We construct the antisymmetric part of two-point cross-correlation between intensity maps of the H I 21 cm line and the CO 2.61 mm line, arising because the statistical fluctuations of two fields have different evolution in time. We show that the sign of this new signal can distinguish model-independently whether inside-out reionization happens during some interval of time. More importantly, within the framework of the excursion set model of reionization, we demonstrate that the slope of the dipole of H I-CO cross-power spectrum at large scales is linear to the rate of change of global neutral fraction of hydrogen in a manner independent of reionization parameters, until the slope levels out near the end of reionization, but this trend might possibly depend on the framework of reionization modelling. The H I-CO dipole may be a smoking-gun probe for the speed of reionization, or "standard speedometer" for cosmic reionization. Observations of this new signal will unveil the global reionization history from the midpoint to near the completion of reionization.
