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arXiv 0901.0810astro-ph.CO
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QUaD CMB极化实验的宇宙学参数

Cosmological Parameters from the QUaD CMB polarization experiment

QUaD collaboration, P. G. Castro, P. Ade, J. Bock, M. Bowden, M. L. Brown, G. Cahill, S. Church, T. Culverhouse, R. B. Friedman, K. Ganga, W. K. Gear, S. Gupta,… 展开作者

QUaD collaboration, P. G. Castro, P. Ade, J. Bock, M. Bowden, M. L. Brown, G. Cahill, S. Church, T. Culverhouse, R. B. Friedman, K. Ganga, W. K. Gear, S. Gupta, J. Hinderks, J. Kovac, A. E. Lange, E. Leitch, S. J. Melhuish, Y. Memari, J. A. Murphy, A. Orlando, C. Pryke, R. Schwarz, C. O'Sullivan, L. Piccirillo, N. Rajguru, B. Rusholme, A. N. Taylor, K. L. Thompson, A. H. Turner, E. Y. S. Wu, M. Zemcov

摘要:

本文利用QUaD实验对第二、三季的偏振和温度功率谱进行了参数估计分析。QUaD首次在E模式偏振光谱中检测到多个具有高度显著性的声学峰。虽然QUaD的参数约束与以前的标准6参数LCDM宇宙学的结果没有竞争力,但它们确实首次允许有意义的仅偏振参数分析。在一个标准的6参数LCDM分析中,我们发现QUaD TT功率谱与以前的结果吻合得很好。然而,QUaD偏振数据显示出与LCDM的一些张力。这个1到2西格玛张力的起源仍然不清楚,可能指向新的物理学,剩余系统学或简单的随机机会。我们还将QUaD与五年WMAP数据集和SDSS Luminous Red Galerkin第四次数据发布功率谱相结合,并扩展我们的分析以约束单个等曲率模分数,约束冷暗物质密度,α(cdmi)<0.11(95% CL),中微子密度,α(ndi)<0.26(95% CL),中微子速度,α(nvi)<0.23(95% CL),modes.我们的分析为未来的极化实验设定了一个基准。

英文摘要:

In this paper we present a parameter estimation analysis of the polarization and temperature power spectra from the second and third season of observations with the QUaD experiment. QUaD has for the first time detected multiple acoustic peaks in the E-mode polarization spectrum with high significance. Although QUaD-only parameter constraints are not competitive with previous results for the standard 6-parameter LCDM cosmology, they do allow meaningful polarization-only parameter analyses for the first time. In a standard 6-parameter LCDM analysis we find the QUaD TT power spectrum to be in good agreement with previous results. However, the QUaD polarization data shows some tension with LCDM. The origin of this 1 to 2 sigma tension remains unclear, and may point to new physics, residual systematics or simple random chance. We also combine QUaD with the five-year WMAP data set and the SDSS Luminous Red Galaxies 4th data release power spectrum, and extend our analysis to constrain individual isocurvature mode fractions, constraining cold dark matter density, alpha(cdmi)<0.11 (95 % CL), neutrino density, alpha(ndi)<0.26 (95 % CL), and neutrino velocity, alpha(nvi)<0.23 (95 % CL), modes. Our analysis sets a benchmark for future polarization experiments.

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。

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