Physics of the Dark Universe ( IF 5.0 ) Pub Date : 2020-05-11 , DOI: 10.1016/j.dark.2020.100585 Xiu-Hui Tan , Ji-Ping Dai , Jun-Qing Xia
In this paper, we estimate the cross-correlation power spectra between the Planck 2018 cosmic microwave background (CMB) temperature anisotropy map and the unresolved -ray background (UGRB) from the 9-years Fermi-Large Area Telescope (LAT) data. In this analysis, we use up to nine energy bins over a wide energy range of [0.631, 1000] GeV from the Fermi-LAT UGRB data. Firstly, we find that the Fermi data with the energy ranges [1.202, 2.290] GeV and [17.38, 36.31] GeV show the positive evidence for the Integrated Sachs-Wolfe (ISW) effect at confidence level, and the significance would be increased to when using these two energy bins together. Secondly, we apply the single power-law model to normalize the amplitude and use all the nine Fermi energy bins to measure the significance of the ISW effect, we obtained (68% C.L.). For the robustness test, we implement a null hypothesis by randomizing the Fermi mock maps of nine energy bins and obtain the non-detection of ISW effect, which confirms that the ISW signal comes from the Fermi-LAT diffuse -ray data and is consistent with the standard CDM model prediction essentially. We use a cross-correlation coefficient to show the relation between different energy bins. Furthermore, we vary the cut ranges of galactic plane on the mask of Fermi map and carefully check the consequent influence on the ISW signal detection.
中文翻译:
从费米-LAT扩散中寻找综合的萨克斯-沃尔夫效应射线图
在本文中,我们估计了Planck 2018宇宙微波背景(CMB)温度各向异性图与未解析图之间的互相关功率谱9年费米-大面积望远镜(LAT)数据得出的X射线背景(UGRB)。在此分析中,根据费米-LAT UGRB数据,我们在[ 0.631,1000 ] GeV的宽能量范围内使用了多达9个能量仓。首先,我们发现能量范围为[1.202,2.290] GeV和[17.38,36.31] GeV的费米数据显示了萨克斯-沃尔夫综合(ISW)效应的积极证据。 置信水平,其重要性将提高到 当同时使用这两个能量箱时。其次,我们使用单幂定律模型对幅度进行归一化,并使用所有9个费米能量箱来测量ISW效应的显着性,(68%CL)。对于鲁棒性测试,我们通过随机化九个能量箱的费米模拟图来实现零假设,并获得未检测到ISW效应的结果,这证实了ISW信号来自费米-LAT扩散射线数据并符合标准 CDM模型预测本质上。我们使用互相关系数来显示不同能量仓之间的关系。此外,我们改变切割范围在费米地图的蒙版上检查银河平面,并仔细检查其对ISW信号检测的影响。