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In the current era of high-precision CMB experiments, the imprint of gravitational lensing on the CMB temperature is exploited as a source of valuable information. Especially the reconstruction of the lensing potential power spectrum is of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Philipp M. Merkel , Bjoern Malte Schaefer

We present limits to the amplitude of non-Gaussian primordial fluctuations in the WMAP 1-year cosmic microwave background sky maps. A non-linear coupling parameter, f_NL, characterizes the amplitude of a quadratic term in the primordial…

It is widely believed that maximum likelihood estimators must be used to provide optimal estimates of power spectra. Since such estimators require require of order N_d^3 operations they are computationally prohibitive for N_d greater than a…

Astrophysics · Physics 2008-11-26 G. Efstathiou

We present simulations of the Cosmic Microwave Background Radiation (CMBR) power spectrum for a class of mixed, non-Gaussian, primordial random fields. We assume a skew positive mixed model with adiabatic inflation perturbations plus…

Astrophysics · Physics 2009-11-10 Ana Paula Andrade , Carlos Alexandre Wuensche , Andre Luiz B. Ribeiro

It is possible to classify pixels of a smoothed cosmic microwave background (CMB) fluctuation map according to their local curvature in ``hill'', ``lake'' and ``saddle'' regions. In the Gaussian case, fractional areas occupied by pixels of…

Astrophysics · Physics 2011-05-10 O. Doré , S. Colombi , F. R. Bouchet

The existence of a cosmic background of primordial gravitational waves (PGWB) is a robust prediction of inflationary cosmology, but it has so far evaded discovery. The most promising avenue of its detection is via measurements of Cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-16 Kai Yi , Yanan Fan , Jan Hamann , Pietro Liò , Yuguang Wang

We investigate the impact of instrumental systematic errors in interferometric measurements of the cosmic microwave background (CMB) temperature and polarization power spectra. We simulate interferometric CMB observations to generate mock…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-06 Le Zhang , Ata Karakci , Paul M. Sutter , Emory F. Bunn , Andrei Korotkov , Peter Timbie , Gregory S. Tucker , Benjamin D. Wandelt

When fitting cosmological models to data, a Bayesian framework is commonly used, requiring assumptions on the form of the likelihood and model prior. In light of current tensions between different data, it is interesting to investigate the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-31 Jordan Krywonos , Simone Paradiso , Alex Krolewski , Shahab Joudaki , Will Percival

We show that the popular ILC approach is unstable in respect to the division of the sample of map pixels to the set of ``homogeneous'' subsamples. For suitable choice of such subsamples we can obtain the restored CMB signal with amplitudes…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-18 A. Doroshkevich , O. Verkhodanov

We test the hypothesis that the temperature of the cosmic microwave background is consistent with a Gaussian random field defined on the celestial sphere, using de-biased internal linear combination (DILC) map produced from the 3-year WMAP…

Astrophysics · Physics 2010-11-11 Lung-Yih Chiang , Pavel D. Naselsky , Peter Coles

We report a measurement of the E-mode polarization power spectrum of the cosmic microwave background (CMB) using 150 GHz data taken from July 2014 to December 2016 with the POLARBEAR experiment. We reach an effective polarization map noise…

We present the final nine-year maps and basic results from the WMAP mission. We provide new nine-year full sky temperature maps that were processed to reduce the asymmetry of the effective beams. Temperature and polarization sky maps are…

Strong foreground contamination in high resolution CMB data requires masking which introduces statistical anisotropies and renders a full maximum likelihood analysis numerically intractable. Standard analysis methods like the pseudo-C_l…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-26 H. F. Gruetjen , E. P. S. Shellard

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

In this follow-up work to the High Energy Physics Community Summer Study 2013 (HEP CSS 2013, a.k.a. Snowmass), we explore the scientific capabilities of a future Stage-IV Cosmic Microwave Background polarization experiment (CMB-S4) under…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-11 W. L. K. Wu , J. Errard , C. Dvorkin , C. L. Kuo , A. T. Lee , P. McDonald , A. Slosar , O. Zahn

Angular power spectrum of the cosmic microwave background (CMB) temperature anisotropies is one of the most important on characteristics of the Universe such as its geometry and total density. Using flat sky approximation and Fourier…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Lung-Yih Chiang , Fei-Fan Chen

All the analyses of Cosmic Microwave Background (CMB) temperature maps up--to--date show that CMB anisotropies follow a Gaussian distribution. On the other hand, astrophysical foregrounds which hamper the detection of the CMB angular power…

Astrophysics · Physics 2008-11-26 F. Argüeso , J. González-Nuevo , L. Toffolatti

CMB full-sky temperature data show a hemispherical asymmetry in power nearly aligned with the Ecliptic. In real space, this anomaly can be quantified by the temperature variance in the northern and southern Ecliptic hemispheres, with the…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Marcio O'Dwyer , Craig J. Copi , Johanna M. Nagy , C. Barth Netterfield , John Ruhl , Glenn D. Starkman