A high-significance detection of non-Gaussianity in the WMAP 5-yr data using directional spherical wavelets

@article{McEwen2006AHD,
  title={A high-significance detection of non-Gaussianity in the WMAP 5-yr data using directional spherical wavelets},
  author={Jason D. McEwen and M. P. Hobson and Anthony N. Lasenby and Daniel J. Mortlock},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2006},
  volume={388},
  pages={659-662}
}
  • J. McEwen, M. Hobson, D. Mortlock
  • Published 13 April 2006
  • Geology, Environmental Science
  • Monthly Notices of the Royal Astronomical Society
We repeat the directional spherical real Morlet wavelet analysis, used previously to detect non-Gaussianity in the Wilkinson Microwave Anisotropy Probe (WMAP) 1- and 3-yr data, on the WMAP 5-yr data. The non-Gaussian signal detected previously is present in the 5-yr data at a slightly increased statistical significance of approximately 99 per cent. Localized regions that contribute most strongly to the non-Gaussian signal are found to be very similar to those detected in the previous releases… 

Figures from this paper

Non-Gaussianity analysis on local morphological measures of WMAP data

The decomposition of a signal on the sphere with the steerable wavelet constructed from the second Gaussian derivative gives access to the orientation, signed-intensity and elongation of the signal's

Non-Gaussian signatures in the five-year WMAP data as identified with isotropic scaling indices

We continue the analysis of non-Gaussianities in the cosmic microwave background by means of the scaling index method by applying this method on the single Q, V, W bands and the co-added VW band of

Search for Non-Gaussianities in the WMAP Data with the Scaling Index Method

TLDR
The so-called Scaling Index Method (SIM) was used for comparing the data set with simulations as well as surrogates, which are full-sky maps generated by randomisation of previously selected features of the original map.

Scalar quantities as detectors of non-Gaussianity on CMB maps

We study the power of several scalar quantities constructed on the sphere (presented in Monteserin et al. 2005) to detect non-Gaussianity on the temperature distribution of the cosmic microwave

Wilkinson Microwave Anisotropy Probe 7‐yr constraints on fNL with a fast wavelet estimator

A new method to constrain the local non-linear coupling parameter fNL based on a fast wavelet decomposition is presented. Using a multiresolution wavelet adapted to the HEALPix pixelization, we have

Non-Gaussianity in the HILC foreground-reduced three-year WMAP CMB map

A detection or nondetection of primordial non-Gaussianity in the CMB data is essential not only to test alternative models of the physics of the early universe but also to discriminate among classes

INCREASING EVIDENCE FOR HEMISPHERICAL POWER ASYMMETRY IN THE FIVE-YEAR WMAP DATA

Motivated by the recent results of Hansen et al. concerning a noticeable hemispherical power asymmetry in the Wilkinson Microwave Anisotropy Probe (WMAP) data on small angular scales, we revisit the

Scaling Indices Applied to the WMAP 5-Year Data

We continue the analysis of non-Gaussianities in the CMB by means of the scaling index method (SIM, Rath, Schuecker and Banday 2007) by applying this method on the single Q-, V-, W-bands and the

Analysis of non‐Gaussian cosmic microwave background maps based on the N‐pdf. Application to Wilkinson Microwave Anisotropy Probe data

We present a new method based on the N-point probability distribution function (N-pdf) to study non-Gaussianity in cosmic microwave background maps. Likelihood and Bayesian estimation are applied to
...

References

SHOWING 1-10 OF 139 REFERENCES

A high-significance detection of non-Gaussianity in the Wilkinson Microwave Anisotropy Probe 1-yr data using directional spherical wavelets

A directional spherical wavelet analysis is performed to examine the Gaussianity of the Wilkinson Microwave Anisotropy Probe (WMAP) 1-yr data. Such an analysis is facilitated by the introduction of a

Detection of Non-Gaussianity in the Wilkinson Microwave Anisotropy Probe First-Year Data Using Spherical Wavelets

TLDR
The non-Gaussian detection in the Wilkinson Microwave Anisotropy Probe (WMAP) first-year data implies not only asymmetries north/south—like other previous WMAP analyses—but also a direct non- Gaussian detection.

The Non-Gaussian Cold Spot in the 3 Year Wilkinson Microwave Anisotropy Probe Data

The non-Gaussian cold spot detected in wavelet space in the WMAP 1 yr data is detected again in the co-added WMAP 3 yr data at the same position (b = -57°, l = 209°) and size in the sky (≈10°). The

Wavelets and WMAP non-Gaussianity

We study the statistical properties of the first-year Wilkinson Microwave Anisotropy Probe (WMAP) data on different scales using the spherical Mexican hat wavelet transform. Consistent with the 2004

Non-Gaussianity analysis on local morphological measures of WMAP data

The decomposition of a signal on the sphere with the steerable wavelet constructed from the second Gaussian derivative gives access to the orientation, signed-intensity and elongation of the signal's

Non-Gaussianity in the WMAP data using the peak-peak correlation function

We present a search for non-Gaussianity in the WMAP first-year data using the two-point correlation function of maxima and minima in the temperature map. We find evidence for non-Gaussianity on large

The non-Gaussian Cold Spot in the 3-year WMAP data

The non-Gaussian cold spot detected in wavelet space in the WMAP 1-year data, is detected again in the coadded WMAP 3-year data at the same position (b = -57, l = 209) and size in the sky (around 10

Non-Gaussianity detections in the Bianchi VIIh corrected WMAP one-year data made with directional spherical wavelets

Many of the current anomalies reported in the WMAP text (WMAP) one-year data disappear after ‘correcting’ for the best-fitting embedded Bianchi type VIIh component, albeit assuming no dark energy

Detection of a non‐Gaussian spot in WMAP

An extremely cold and big spot in the Wilkinson Microwave Anisotropy Probe (WMAP) 1-yr data is analysed. Our work is a continuation of a previous paper by Vielva et al. that reported the detection of

Wavelets and Wilkinson Microwave Anisotropy Probe Non-Gaussianity

We study the statistical properties of the first-year Wilkinson Microwave Anisotropy Probe (WMAP) data on different scales using the spherical Mexican hat wavelet transform. Consistent with the 2004
...