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Related papers: Understanding the WMAP Cold Spot mystery

200 papers

The non-Gaussian Cold Spot (CS) surrounded by its hot ring is one of the most striking features of the CMB. It has been speculated that either new physics or ISW effect induced by the presence of a cosmic void at high redshift can account…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-19 Diego Garcia Lambas , Frode K. Hansen , Facundo Toscano , Heliana E. Luparello , Ezequiel F. Boero

The report of a significant deviation of the CMB temperature anisotropies distribution from Gaussianity (soon after the public release of the WMAP data in 2003) has become one of the most solid WMAP anomalies. This detection grounds on an…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 P. Vielva

In a concordant $\Lambda$ Cold Dark Matter ($\Lambda$CDM) model, large-angle Cosmic Microwave Background (CMB) temperature anisotropy due to linear perturbations in the local universe is not negligible. We explore a possible role of an…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-09 Kaiki Taro Inoue

Both WMAP and PLANCK missions reported the extremely Cold Spot (CS) centered at Galactic coordinate ($l=209^{\circ}$, $b=-57^{\circ}$) in CMB map. In this paper, we study the local non-Gaussianity of CS by defining the local Minkowski…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-28 Wen Zhao

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…

Astrophysics · Physics 2009-08-26 Sudeep Das , David N. Spergel

Statistical Isotropy of the Cosmic Microwave Background (CMB) radiation has been studied and debated extensively in recent years. Under this assumption, the hot spots and cold spots of the CMB are expected to be uniformly distributed over a…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-14 Md Ishaque Khan , Rajib Saha

One of the most interesting explanations for the non-Gaussian Cold Spot (CS) detected in the WMAP data by Vielva et al. 2004, is that it arises from the interaction of the CMB radiation with a cosmic texture (Cruz et al. 2007b). In this…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 P. Vielva , E. Martinez-Gonzalez , M. Cruz , R. B. Barreiro , M. Tucci

In the present work, we study the largest structures of the CMB temperature measured by Planck in terms of the most prominent peaks on the sky, which, in particular, are located in the southern galactic hemisphere. Besides these large-scale…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-17 A. Marcos-Caballero , E. Martínez-González , P. Vielva

We investigate the local properties of WMAP Cold Spot (CS) by defining the local statistics: mean temperature, variance, skewness and kurtosis. We find that, compared with the \emph{coldest spots} in random Gaussian simulations, WMAP CS…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-30 Wen Zhao

Recent results of the ESA Planck satellite have confirmed the existence of some anomalies in the statistical distribution of the cosmic microwave background (CMB) anisotropies. One of the most intriguing anomalies is the Cold Spot, firstly…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 R. Fernández-Cobos , P. Vielva , E. Martínez-González , M. Tucci , M. Cruz

We study the large-scale angular correlation signatures of the Cosmic Microwave Background (CMB) temperature fluctuations from WMAP data in several spherical cap regions of the celestial sphere, outside the Kp0 or Kp2 cut-sky masks. We…

A search for matched circle pairs of similar temperature fluctuations in the final WMAP 9yr data is carried out. Such a signature is expected if the space of the Universe is multiply connected. We investigate the relation between the pixel…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-22 Ralf Aurich , Sven Lustig

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…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-30 Armando Bernui

Significant alignment and signed-intensity anomalies of local features of the cosmic microwave background (CMB) are detected on the three-year WMAP data, through a decomposition of the signal with steerable wavelets on the sphere. Firstly,…

Astrophysics · Physics 2009-09-29 P. Vielva , Y. Wiaux , E. Martinez-Gonzalez , P. Vandergheynst

We estimate the power spectra of CMB temperature anisotropy in localized regions on the sky using the WMAP 7-year data. Here, we report that the north hat and the south hat regions at the high Galactic latitude (|b| >= 30 deg) show anomaly…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-18 Kyeong Yeon Ko , Chan-Gyung Park , Jai-chan Hwang

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…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-19 Stephen Owusu , Pedro da Silveira Ferreira , Alessio Notari , Miguel Quartin

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,…

Astrophysics · Physics 2009-11-13 Y. Wiaux , P. Vielva , R. B. Barreiro , E. Martinez-Gonzalez , P. Vandergheynst

We investigate the sources of parity asymmetry in the CMB temperature maps using a pixel domain approach. We demonstrate that this anomaly is mainly associated with the presence of two pairs of high asymmetry regions. The first pair of…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-14 James Creswell , Pavel Naselsky

Measurement of the acoustic peaks of the cosmic microwave background (CMB) temperature anisotropies has been instrumental in deciding the geometry and content of the universe. Acoustic peak positions vary in different parts of the sky due…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-11 Lung-Yih Chiang

The recent study of BOOMERanG 150 GHz Cosmic Microwave Background (CMB) radiation maps have detected ellipticity of the temperature anisotropy spots independent on the temperature threshold. The effect has been found for spots up to several…

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