Related papers: Probing CMB Cold Spot through Local Minkowski Func…
The cosmic microwave background radiation is supposed to be Gaussian and this hypothesis is in good agreement with the recent very accurate measurements. Nonetheless a tiny amount of non-Gaussianity is predicted by the standard inflation…
We test the statistical isotropy and Gaussianity of the cosmic microwave background (CMB) anisotropies using observations made by the Planck satellite. Our results are based mainly on the full Planck mission for temperature, but also…
The detection of the magnetic type $B$-mode polarization is the main goal of future cosmic microwave background (CMB) experiments. In the standard model, the $B$-mode map is a strongly non-gaussian field due to the lensed component. Besides…
The Cosmic Microwave Background (CMB) anisotropies are thought to be statistically isotropic and Gaussian. However, several anomalies are observed, including the CMB Cold Spot, an unexpected cold $\sim 10^{\circ}$ region with $p$-value…
We present a careful frequentist analysis of one- and two-point statistics of the hot and cold spots in the cosmic microwave background (CMB) data obtained by the Wilkinson Microwave Anisotropy Probe (WMAP). Our main result is the detection…
Several intriguing phenomena, unlikely within the standard inflationary cosmology, were reported in the cosmic microwave background (CMB) data from WMAP and appear to be uncorrelated. Two of these phenomena, termed CMB anomalies, are…
We derive analytical formulae for the Minkowski Functions of the cosmic microwave background (CMB) and large-scale structure (LSS) from primordial non-Gaussianity. These formulae enable us to estimate a non-linear coupling parameter, f_NL,…
In this paper, we investigate the utility of Minkowski Functionals as a probe of cold/hot disk-like structures in the CMB. In order to construct an accurate estimator, we resolve a long-standing issue with the use of Minkowski Functionals…
In this work we effectively calculated the two-dimensional Minkowski functionals for cosmic microwave background (CMB) temperature maps generated by single field models of inflation with a standard kinetic term. We started with calculation…
Cosmologists have suggested a number of intriguing hypotheses for the origin of the "WMAP cold spot", the coldest extended region seen in the CMB sky, including a very large void and a collapsing texture. Either hypothesis predicts a…
We present a Gaussianity test of the cosmic microwave background (CMB) polarization by analyzing the statistics of unpolarized points in the sky, classified into three distinct types: saddles, comets, and beaks. This classification of…
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 local features. In the present work,…
We detect a dip of 20-45% in the surface brightness and number counts of NVSS sources smoothed to a few degrees at the location of the WMAP cold spot. The dip has structure on scales of approximately 1-10 degrees. Together with independent…
We suggest novel statistics for the CMB maps that are sensitive to non-Gaussian features. These statistics are natural generalizations of the geometrical and topological methods that have been already used in cosmology such as the…
The WMAP cold spot was found by applying spherical wavelets to the first year WMAP data. An excess of kurtosis of the wavelet coefficient was observed at angular scales of around 5 degrees. This excess was shown to be inconsistent with…
We present quantitative investigations of the weak lensing effect on the two-point correlation functions of local maxima (hotspots), $\xipk(\theta)$, in the cosmic microwave background (CMB) maps. The lensing effect depends on the projected…
Two of the most commonly used tools to constrain the primordial non-Gaussianity are the bispectrum and the Minkowski functionals of CMB temperature anisotropies. These two measures of non-Gaussianity in principle provide distinct (though…
Minkowski functionals are summary statistics that capture the geometric and morphological properties of fields. They are sensitive to all higher order correlations of the fields and can be used to complement more conventional statistics,…
We forecast the detectability of the lensing footprint of a collapsing cosmic texture, a topological defect proposed as an explanation of the CMB Cold Spot. Our pipeline is a quadratic, template-amplitude estimator for localized,…
The "Cold Spot" in the CMB sky could be due to the presence of an anomalous huge spherical underdense region - a "Void" - of a few hundreds Mpc/h radius. Such a structure would have an impact on the CMB two-point (power spectrum) and…