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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,…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-08 Pedro da Silveira Ferreira , Stephen Owusu

The cosmic microwave background radiation provides unique constraints on cosmological models. In this Letter we present a summary of the spatial properties of the cosmic microwave background radiation based on the full 4 years of COBE DMR…

(Abridged) Despite the great success of precision cosmology, cosmologists cannot fully explain the initial conditions of the Universe. Inflation, an exponential expansion in the first 10^-36s, is a promising potential explanation. A generic…

Instrumentation and Methods for Astrophysics · Physics 2012-09-07 Immanuel Buder

Cosmic microwave background (CMB) experiments generally infer a temperature fluctuation from a measured intensity fluctuation through the first term in the Taylor expansion of the Planck function, the relation between the intensity in a…

Astrophysics · Physics 2009-11-07 M. Kamionkowski , Lloyd Knox

A new map of the sky representing the degree of randomness in the cosmic microwave background (CMB) temperature has been obtained. The map based on estimation of the Kolmogorov stochasticity parameter clearly distinguishes the contribution…

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

We compute the three-point temperature correlation function of the {\it COBE} Differential Microwave Radiometer (DMR) first-year sky maps to search for non-Gaussian temperature fluctuations. The level of fluctuations seen in the computed…

We study the angular distribution of temperature fluctuations in the cosmic microwave background (CMB) to probe the statistical isotropy of the universe by using precise full-sky CMB data with a model-independent approach. We investigated…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-01 C. E. Kester , A. Bernui , W. S. Hipólito-Ricaldi

This paper presents a novel approach to constrain the $\mu$- and y- distortions in the Cosmic Microwave Background (CMB) using the COBE/FIRAS data. The analysis draws from the concept of blackbody radiation inversion (BRI), a mathematical…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-06 Somita Dhal , Koustav Konar , R. K. Paul

This work presents a detailed analysis of Cosmic Microwave Background (CMB) radiation intensity observations. The CMB is a relic of the Big Bang and its study greatly enhances our knowledge of cosmology. This work has led to new values for…

Astrophysics · Physics 2007-05-23 Henrik P. Nordberg , George F. Smoot

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

It is possible to reduce the discrepancy between the local measurement of the cosmological parameter $H_0$ and the value derived from the $Planck$ measurements of the Cosmic Microwave Background (CMB) by considering contamination of the CMB…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-27 V. N. Yershov , A. A. Raikov , N. Yu. Lovyagin , N. P. M. Kuin , E. A. Popova

A key assumption of the standard cosmological model is that the temperature of the cosmic microwave background (CMB) radiation scales with cosmological redshift $z$ as $T_{\rm CMB}(z) \propto (1+z)$ at all times after recombination at…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-10 J. Colin Hill , Boris Bolliet

During the transition from a neutral to a fully reionized universe, scattering of cosmic microwave background (CMB) photons via free-electrons leads to a new anisotropy contribution to the temperature distribution. If the reionization…

Astrophysics · Physics 2009-11-10 Asantha Cooray

The standard $\Lambda$CDM model has been highly successful in describing cosmic microwave background (CMB) observations. Nevertheless, a set of large-scale statistical anomalies persists in temperature anisotropies across WMAP and Planck.…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-23 Jiazheng Dou , Wen Zhao

Local dissipation of RF power in superconducting radio frequency cavities create so called hot spots, primary precursors of cavity quench driven by either thermal or magnetic instability. These hot spots are detected by a temperature…

Superconductivity · Physics 2023-08-21 B. D. Khanal , P. Dhakal , G. Ciovati

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 recently detected polarization of the cosmic microwave background (CMB) holds the potential for revealing the physics of inflation and gravitationally mapping the large-scale structure of the universe, if so called B-mode signals below…

Astrophysics · Physics 2011-05-12 Wayne Hu , Matthew M. Hedman , Matias Zaldarriaga

Following the pioneering observations with COBE in the early 1990s, studies of the cosmic microwave background (CMB) have focused on temperature and polarization anisotropies. CMB spectral distortions - tiny departures of the CMB energy…

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
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