arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1107.2654astro-ph.CO
收藏

通过普朗克射电星表检验WMAP宇宙学

Testing the WMAP cosmology via Planck radio catalogues

J. R. Whitbourn, T. Shanks, U. Sawangwit

摘要:

支持标准LCDM宇宙学模型的主要证据是WMAP和其他微波实验观测到的CMB功率谱。但是Sawangwit和Shanks(2010)最近表明,WMAP CMB功率谱对WMAP望远镜的光束轮廓高度敏感。在这里,我们使用的源目录从普朗克早期数据发布进一步测试的WMAP光束轮廓。我们确认,在Q,V,特别是在W堆叠的光束轮廓出现比预期的更宽时,木星光束相比,规范化直接的射电源配置文件或使用普朗克通量。基于WMAP-CMB自由源目录和NVSS源的计算也得到了同样的结果。我们的光束轮廓测量的准确性得到了CMB天空模拟分析的支持。然而,来自WMAP 7的W波段的波束轮廓比先前在WMAP 5数据中发现的要窄,并且WMAP波束的抑制现在仅在~3sigma水平。我们还发现,WMAP源通量表现出可能的非线性与普朗克通量。但是,包括Weiland等人(2011)明亮源的地基和普朗克数据可能表明,这种差异是线性偏移而不是非线性。此外,我们还发现Planck观测到的~151个星系团的Sunyaev-Zel'dovich(SZ)叠加衰减与WMAP数据一致。我们发现,没有证据表明WMAP SZ赤字,如先前报道的。在昏迷的特殊情况下,我们发现的证据存在一个~0.1mK的向下CMB波动。我们的结论是,光束轮廓系统学可以有显着的影响的幅度和位置的声学峰,具有潜在的重要意义的宇宙学参数拟合。

英文摘要:

The prime evidence underpinning the standard LCDM cosmological model is the CMB power spectrum as observed by WMAP and other microwave experiments. But Sawangwit & Shanks (2010) have recently shown that the WMAP CMB power spectrum is highly sensitive to the beam profile of the WMAP telescope. Here, we use the source catalogue from the Planck Early Data Release to test further the WMAP beam profiles. We confirm that stacked beam profiles at Q, V and particularly at W appear wider than expected when compared to the Jupiter beam, normalised either directly to the radio source profiles or using Planck fluxes. The same result is also found based on WMAP-CMBfree source catalogues and NVSS sources. The accuracy of our beam profile measurements is supported by analysis of CMB sky simulations. However the beam profiles from WMAP7 at the W band are narrower than previously found in WMAP5 data and the rejection of the WMAP beam is now only at the ~3sigma level. We also find that the WMAP source fluxes demonstrate possible non-linearity with Planck fluxes. But including ground-based and Planck data for the bright Weiland et al (2011) sources may suggest that the discrepancy is a linear offset rather than a non-linearity. Additionally, we find that the stacked Sunyaev-Zel'dovich (SZ) decrements of ~151 galaxy clusters observed by Planck are in agreement with the WMAP data. We find that there is no evidence for a WMAP SZ deficit as has previously been reported. In the particular case of Coma we find evidence for the presence of an ~0.1mK downwards CMB fluctuation. We conclude that beam profile systematics can have significant effects on both the amplitude and position of the acoustic peaks, with potentially important implications for cosmology parameter fitting.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑