Constraints on primordial non-Gaussianity from a needlet analysis of the WMAP-5 data
Constraints on primordial non-Gaussianity from a needlet analysis of the WMAP-5 data
复制标题
WMAP-5 数据针刺分析对原始非高斯性的约束
DOI：
10.1111/j.1365-2966.2009.14847.x
复制
发表时间：
2008
影响因子：
4.8
通讯作者：
N. Vittorio
中科院分区：
文献类型：
--
作者：
D. Pietrobon;P. Cabella;A. Balbi;G. Gasperis;N. Vittorio
我们通过执行基于针尖的数据分析，在Wilkinson微波各向异性探测器(WMAP)5年温度各向异性图中寻找非高斯信号。我们使用WMAP团队通过W、V和Q通道的优化组合获得的前景缩减地图，并进行逼真的非高斯模拟，以约束非线性耦合参数f nL。我们应用针尖系数偏度的三阶估计，并计算其分布的χ2统计量。我们在95%的置信度下得到了−80<；f NL<；120，它符合高斯分布，与以前对非线性耦合的约束条件相当。然后，我们基于相同的模拟开发了f_nL的估计量，并且我们发现原始非高斯性的约束是一致的。最后，我们计算了针尖空间的三点相关函数：在95%的置信度水平下，对fNL的约束改进到−50<；fNL<；110。
We look for a non-Gaussian signal in the Wilkinson Microwave Anisotropy Probe (WMAP) 5-year temperature anisotropy maps by performing a needlet-based data analysis. We use the foreground-reduced maps obtained by the WMAP team through the optimal combination of the W, V and Q channels, and perform realistic non-Gaussian simulations in order to constrain the non-linear coupling parameter f NL. We apply a third-order estimator of the needlet coefficients skewness and compute the χ 2 statistics of its distribution. We obtain −80 <f NL < 120 at 95 per cent confidence level, which is consistent with a Gaussian distribution and comparable to previous constraints on the non-linear coupling. We then develop an estimator of f NL based on the same simulations and we find consistent constraints on primordial non-Gaussianity. We finally compute the three-point correlation function in needlet space: the constraints on f NL improve to −50 <f NL < 110 at 95 per cent confidence level.
DOI：
10.1088/0004-637x/692/2/1221
发表时间：
2008-05
期刊：
The Astrophysical Journal
影响因子：
--
作者：
QUaD collaboration J. R. Hinderks;P. Ade;J. Bock;M. Bowden;M. L. Brown;G. Cahill;J. Carlstrom;P. G. Castro;S. Church;T. Culverhouse;R. Friedman;K. Ganga;W. Gear;S. Gupta;J. Harris;V. Haynes;B. Keating;J. Kovac;E. Kirby;A. E. Lange;E. Leitch;O. Mallie;S. Melhuish;Y. Memari;J. A. Murphy;A. Orlando;R. Schwarz;C. O'Sullivan;L. Piccirillo;C. Pryke;N. Rajguru;B. Rusholme;A. Taylor;K. Thompson;C. Tucker;A. H. Turner;E. Y. S. Wu;M. University;Nasa Goddard Cardiff University;Jpl Caltech University of Edinburgh;U. Cambridge;National University of Ireland Maynooth;U. Chicago;Universidade T'ecnica de Lisboa;Laboratoire Apccnrs;U. Manchester;University of California San Diego University College London-University-of-California-San-Diego-University-2303464988
通讯作者：
QUaD collaboration J. R. Hinderks;P. Ade;J. Bock;M. Bowden;M. L. Brown;G. Cahill;J. Carlstrom;P. G. Castro;S. Church;T. Culverhouse;R. Friedman;K. Ganga;W. Gear;S. Gupta;J. Harris;V. Haynes;B. Keating;J. Kovac;E. Kirby;A. E. Lange;E. Leitch;O. Mallie;S. Melhuish;Y. Memari;J. A. Murphy;A. Orlando;R. Schwarz;C. O'Sullivan;L. Piccirillo;C. Pryke;N. Rajguru;B. Rusholme;A. Taylor;K. Thompson;C. Tucker;A. H. Turner;E. Y. S. Wu;M. University;Nasa Goddard Cardiff University;Jpl Caltech University of Edinburgh;U. Cambridge;National University of Ireland Maynooth;U. Chicago;Universidade T'ecnica de Lisboa;Laboratoire Apccnrs;U. Manchester;University of California San Diego University College London-University-of-California-San-Diego-University-2303464988