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Cited by 690

The DOI matches its Crossref record; 3 of the 3 references it cites were found in a registry or an index.

First‐Year Wilkinson Microwave Anisotropy Probe ( WMAP ) Observations: Tests of Gaussianity

Open access
Komatsu, E., Kogut, A., Nolta, M. R., Bennett, C. L., Halpern, M., Hinshaw, G., Jarosik, N., Limon, M., Meyer, S. S., Page, L., Spergel, D. N., Tucker, G. S., Verde, L., Wollack, E., Wright, E. L.·2003·The Astrophysical Journal Supplement Series
DOI 10.1086/377220
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Abstract

We present limits to the amplitude of non-Gaussian primordial fluctuations in the WMAP 1 yr cosmic microwave background sky maps. A nonlinear coupling parameter, f NL , characterizes the amplitude of a quadratic term in the primordial potential. We use two statistics: one is a cubic statistic which measures phase correlations of temperature fluctuations after combining all configurations of the angular bispectrum. The other uses the Minkowski functionals to measure the morphology of the sky maps. Both methods find the WMAP data consistent with Gaussian primordial fluctuations and establish limits, -58 < f NL < 134, at 95% confidence. There is no significant frequency or scale dependence of f NL . The WMAP limit is 30 times better than COBE and validates that the power spectrum can fully characterize statistical properties of CMB anisotropy in the WMAP data to a high degree of accuracy. Our results also validate the use of a Gaussian theory for predicting the abundance of clusters in the local universe. We detect a point-source contribution to the bispectrum at 41 GHz, b src = (9.5 ± 4.4) × 10 -5 μK 3 sr 2 , which gives a power spectrum from point sources of c src = (15 ± 6) × 10 -3 μK 2 sr in thermodynamic temperature units. This value agrees well with independent estimates of source number counts and the power spectrum at 41 GHz, indicating that b src directly measures residual source contributions.

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Metadata

Authors
Komatsu, E., Kogut, A., Nolta, M. R., Bennett, C. L., Halpern, M., Hinshaw, G., Jarosik, N., Limon, M., Meyer, S. S., Page, L., Spergel, D. N., Tucker, G. S., Verde, L., Wollack, E., & Wright, E. L.
Venue
The Astrophysical Journal Supplement Series
Publisher
American Astronomical Society
Published
2003-09
Volume
148
Issue
1
Pages
119-134
ISSN
  • 0067-0049 (ISSN-L)
  • 1538-4365
DOI
10.1086/377220
OpenAlex
W2077689059
Cited by
690
References
3
FWCI
57.61
Type
journal article
Language
en
Open access
bronze

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CoChat. (2026). Citation check: First‐Year Wilkinson Microwave Anisotropy Probe ( WMAP ) Observations: Tests of Gaussianity. https://app.cochat.ai/papers/10.1086/377220
The paper
Komatsu, E., Kogut, A., Nolta, M. R., Bennett, C. L., Halpern, M., Hinshaw, G., Jarosik, N., Limon, M., Meyer, S. S., Page, L., Spergel, D. N., Tucker, G. S., Verde, L., Wollack, E., & Wright, E. L. (2003). First‐Year Wilkinson Microwave Anisotropy Probe ( WMAP ) Observations: Tests of Gaussianity. The Astrophysical Journal Supplement Series. https://doi.org/10.1086/377220

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.