Combining CMB datasets with consistent foreground modelling
结合CMB数据集与一致的前景建模
M. Tristram, M. Douspis, A. Gorce, S. Henrot-Versillé, L. T. Hergt, S. Ilic, L. McBride, M. Muñoz-Echeverría, E. Pointecouteau, L. Salvati
AI总结 本文通过联合分析普朗克卫星、阿塔卡马宇宙望远镜和南极望远镜的数据,构建统一的似然函数以建模CMB信号及前景,展示前景建模一致性对参数估计的重要性。
Comments 12 pages, 17 figures, 5 appendix pages. accepted in A&A
详情
- Journal ref
- A&A 710, A165 (2026)
我们提出了一个联合宇宙学分析,结合普朗克卫星、阿塔卡马宇宙望远镜和南极望远镜的数据。我们构建了一个统一的似然函数,通过联合建模宇宙微波背景(CMB)信号、银河系和 extragalactic 前景以及所有数据集的仪器系统误差,以重现测量的温度和偏振功率谱。我们通过结合数据集来减少依赖性,并通过边缘化前景模板的选择来提高参数估计的鲁棒性。在这一联合分析中,ΛCDM参数对前景建模的变化表现出显著的稳定性。宇宙学扩展参数对这些假设更为敏感,边缘化前景模型后,中微子领域不确定性增加高达35%。相比之下,前景参数的确定更强烈依赖于对底层前景模型假设的设定。总体而言,这项工作展示了当前CMB实验完全联合分析的可行性和可靠性,并强调了在下一代高灵敏度CMB调查的科学目标中,一致和准确的前景建模的重要性。
We present a joint cosmological analysis combining data from the Planck satellite, the Atacama Cosmology Telescope, and the South Pole Telescope. We construct a unified likelihood that reproduces the measured temperature and polarisation power spectra by jointly modelling the cosmic microwave background (CMB) signal, Galactic and extragalactic foregrounds, and instrumental systematics across all datasets. We reduce reliance by combining datasets and improve the robustness of parameter estimation by marginalising over the choice of foreground templates. Within this joint analysis, $Λ$CDM parameters exhibit remarkable stability with respect to variations in foreground modelling. Parameters for cosmological extensions are more sensitive to these assumptions, with uncertainties increasing by up to 35% in the neutrino sector after marginalising over foreground models. In contrast, the determination of foreground parameters depends more strongly on the assumptions made about the underlying foreground models. Overall, this work demonstrates the feasibility and reliability of a fully joint analysis of current CMB experiments and emphasizes the importance of consistent and accurate foreground modelling for the scientific goals of next-generation, high-sensitivity CMB surveys.