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A new method for removing point radio sources and other non-Gaussian noise is proposed as a means of improving the accuracy of estimates of the angular power spectrum of the cosmic microwave background (CMB). The main idea of the method is…

Astrophysics · Physics 2009-11-13 Anisa T. Bajkova

In cosmic microwave background (CMB) experiments, foreground-cleaned temperature maps are still contaminated by the residual dipole due to uncertainties of the Doppler dipole direction and microwave radiometer sidelobe. To obtain reliable…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-16 Hao Liu , Ti-Pei Li

Recent observations have indicated a Cosmic Microwave Background (CMB) temperature decrement in the direction of local galaxies within the 2MASS Redshift Survey. We investigate this detection by analyzing its frequency dependence and…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-06 M. Cruz , E. Martínez-González , C. Gimeno-Amo , B. J. Kavanagh , M. Tucci

We update the search for features, due to transient reductions in inflaton's speed of sound, in the Cosmic Microwave Background (CMB) angular power spectrum using Planck 2018 temperature, polarization and lensing data. We develop a new…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-23 Guadalupe Cañas-Herrera , Jesús Torrado , Ana Achúcarro

The statistical expectation values of the temperature fluctuations of cosmic microwave background (CMB) are assumed to be preserved under rotations of the sky. We investigate the statistical isotropy of the CMB anisotropy maps recently…

Astrophysics · Physics 2007-05-23 Tarun Souradeep , Amir Hajian

We revisit the problem of exact CMB likelihood and power spectrum estimation with the goal of minimizing computational cost through linear compression. This idea was originally proposed for CMB purposes by Tegmark et al.\ (1997), and here…

Instrumentation and Methods for Astrophysics · Physics 2015-11-18 E. Gjerløw , L. P. L. Colombo , H. K. Eriksen , K. M. Górski , A. Gruppuso , J. B. Jewell , S. Plaszczynski , I. K. Wehus

We extend to large scales a method proposed in previous work that reconstructs non-parametrically the primordial power spectrum from cosmic microwave background data at high resolution. The improvement is necessary to account for the…

Astrophysics · Physics 2009-11-13 Domenico Tocchini-Valentini , Yehuda Hoffman , Joseph Silk

We extend the previously described CMB Gibbs sampling framework to allow for exact Bayesian analysis of anisotropic universe models, and apply this method to the 5-year WMAP temperature observations. This involves adding support for…

Astrophysics · Physics 2011-02-11 Nicolaas E. Groeneboom , Hans Kristian Eriksen

Local scaling properties of the co-added foreground-cleaned three-year Wilkinson Microwave Anisotropy Probe (WMAP) data are estimated using weighted scaling indices. The scaling index method (SIM) is - for the first time - adapted and…

Astrophysics · Physics 2009-05-21 C. Raeth , P. Schuecker , A. J. Banday

In this study, we apply the Analytical method of Blind Separation (ABS) of the cosmic microwave background (CMB) from foregrounds to estimate the CMB temperature power spectrum from multi-frequency microwave maps. We test the robustness of…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-21 Jian Yao , Le Zhang , Yuxi Zhao , Pengjie Zhang , Larissa Santos , Jun Zhang

We present a method for the computation of the variance of cosmic microwave background (CMB) temperature maps on azimuthally symmetric patches using a fast convolution approach. As an example of the application of the method, we show…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-15 P. Bielewicz , B. D. Wandelt , A. J. Banday

We use the Wilkinson Microwave Anisotropy Probe 7-year data (WMAP7) to further probe point source detection technique in the sky maps of the cosmic microwave background (CMB) radiation. The method by Tegmark et al. for foreground reduced…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-30 H. G. Khachatryan , G. Nurbaeva , D. Pfenniger , G. Meylan

AIMS: One of the most challenging and important problem of digital signal processing in Cosmology is the separation of foreground contamination from cosmic microwave background (CMB). This problem becomes even more difficult in situations,…

Astrophysics · Physics 2008-02-05 Robertio Vio , Paola Andreani

Wilkinson Microwave Anisotropy Probe (WMAP) has provided us with the yet highest resolution all-sky maps of the Cosmic Microwave Background. As a result of thermal Sunyaev-Zel'dovich effect, clusters of galaxies are imprinted as tiny,…

Astrophysics · Physics 2009-11-11 Niayesh Afshordi

Correlations between cosmic microwave background (CMB) temperature, polarization and spectral distortion anisotropies can be used as a probe of primordial non-Gaussianity. Here, we perform a reconstruction of $\mu$-distortion anisotropies…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-02 M. Remazeilles , J. Chluba

A detection or non detection of primordial non--Gaussianity (NG) by using the cosmic microwave background radiation (CMB) is a possible way to break the degeneracy of early universe models. Since a single statistical estimator hardly can be…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 W. A. Cardona , A. Bernui , M. J. Reboucas

Measurements of the cosmic microwave background (CMB) allow high precision observation of the cosmic plasma at redshift z~1100. After the success of the NASA satellite COBE, that in 1992 provided the first detection of the CMB anisotropy,…

Primordial B-mode detection is one of the main goals of current and future cosmic microwave background (CMB) experiments. However, the weak B-mode signal is overshadowed by several Galactic polarized emissions, such as thermal dust emission…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-18 Ye-Peng Yan , Guo-Jian Wang , Si-Yu Li , Jun-Qing Xia

We apply the iterative Expectation-Maximization algorithm (EM) to estimate the power spectrum of the CMB from multifrequency microwave maps. In addition, we are also able to provide a reconstruction of the CMB map. By assuming that the…

Astrophysics · Physics 2009-11-07 E. Martinez-Gonzalez , J. M. Diego , P. Vielva , J. Silk

One of the key steps in Cosmic Microwave Background (CMB) data analysis is component separation to recover the CMB signal from multi-frequency observations contaminated by foreground emissions. Needlet Internal Linear Combination (NILC) is…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-26 Debabrata Adak
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