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We demonstrate a method for reconstructing the weak lensing potential from the Lyman-$\alpha$ forest data. We derive an optimal estimator for the lensing potential on the sky based on the correlation between pixels in real space. This…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-21 R. Benton Metcalf , Nicolas Tessore , Rupert A. C. Croft

Polarization is the next frontier of CMB analysis, but its signal is dominated over much of the sky by foregrounds which must be carefully removed. To determine the efficacy of this cleaning it is necessary to have sensitive tests for…

Astrophysics · Physics 2007-09-06 Duncan Hanson , Douglas Scott , Emory F. Bunn

The remarkable improvement in the estimates of different cosmological parameters in recent years has been largely spearheaded by accurate measurements of the angular power spectrum of Cosmic Microwave Background (CMB) radiation. This has…

Astrophysics · Physics 2011-04-11 Tarun Souradeep , Rajib Saha , Pankaj Jain

We apply a previously developed Gibbs sampling framework to the foreground corrected 3-yr WMAP polarization data and compute the power spectrum and residual foreground template amplitude posterior distributions. We first analyze the…

It is likely that the observed distribution of the microwave background temperature over the sky is only one realization of the underlying random process associated with cosmological perturbations of quantum-mechanical origin. If so, one…

General Relativity and Quantum Cosmology · Physics 2016-08-24 L. P. Grishchuk , Jérôme Martin

One of the main unsolved problems of cosmology is how to maximize the extraction of information from nonlinear data. If the data are nonlinear the usual approach is to employ a sequence of statistics (N-point statistics, counting statistics…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-07 Uros Seljak , Grigor Aslanyan , Yu Feng , Chirag Modi

Cosmological parameters from WMAP 7 year data are re-analyzed by substituting a pixel-based likelihood estimator to the one delivered publicly by the WMAP team. Our pixel based estimator handles exactly intensity and polarization in a joint…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 F. Finelli , A. De Rosa , A. Gruppuso , D. Paoletti

We re-examine the effects of redshift space distortion in all-sky galaxy redshift surveys in the formalism of spherical harmonics. Within this framework we show how one can treat both the large-scale linear effects, and the small-scale…

Astrophysics · Physics 2015-06-24 A. F. Heavens , A. N. Taylor

We consider the effectiveness of foreground cleaning in the recovery of Cosmic Microwave Background (CMB) polarization sourced by gravitational waves for tensor-to-scalar ratios in the range $0<r<0.1$. Using the planned survey area,…

Residual errors in shear measurements, after corrections for instrument systematics and atmospheric effects, can impact cosmological parameters derived from weak lensing observations. Here we combine convergence maps from our suite of…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-06 Andrea Petri , Morgan May , Zoltan Haiman , Jan M. Kratochvil

We consider the reconstruction of the CMB lensing potential and its power spectrum of the full sphere in presence of sky-cuts due to point sources and Galactic contaminations. Those two effects are treated separately. Small regions…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-30 Aurélien Benoit-Lévy , Typhaine Déchelette , Karim Benabed , Jean-François Cardoso , Duncan Hanson , Simon Prunet

Increasingly large areas in cosmic shear surveys lead to a reduction of statistical errors, necessitating to control systematic errors increasingly better. One of these systematic effects was initially studied by Hartlap et al. in 2011,…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-14 Eray Genc , Peter Schneider , Sandra Unruh , Tim Schrabback

We present the angular power spectrum derived from the first-year Wilkinson Microwave Anisotropy Probe (WMAP) sky maps. We study a variety of power spectrum estimation methods and data combinations and demonstrate that the results are…

We consider the issue of hemispherical power asymmetry in the three-year WMAP data, adopting a previously introduced modulation framework. Computing both frequentist probabilities and Bayesian evidences, we find that the model consisiting…

Astrophysics · Physics 2009-11-13 H. K. Eriksen , A. J. Banday , K. M. Gorski , F. K. Hansen , P. B. Lilje

In this article we present a formalism to incorporate the partial-sky maps to the Gibbs ILC algorithm to estimate the joint posterior density of the Cosmic Microwave Background (CMB) signal and the theoretical CMB angular power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-14 Vipin Sudevan , Ujjal Purkayastha , Rajib Saha

We use quadratic maximum-likelihood (QML) estimators to constrain models with Gaussian but statistically anisotropic Cosmic Microwave Background (CMB) fluctuations, using CMB maps with realistic sky-coverage and instrumental noise. This…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-06 Duncan Hanson , Antony Lewis

The weak lensing power spectrum is a powerful tool to probe cosmological parameters. Additionally, lensing peak counts contain cosmological information beyond the power spectrum. Both of these statistics can be affected by the preferential…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-07 Jia Liu , Zoltán Haiman , Lam Hui , Jan M. Kratochvil , Morgan May

In this paper we implement an improved (error sensitive) Richardson-Lucy deconvolution algorithm on the measured angular power spectrum from the WMAP 3 year data to determine the primordial power spectrum assuming different points in the…

Astrophysics · Physics 2008-12-18 Arman Shafieloo , Tarun Souradeep

A previous work (Monteser\'in et al. 2008) estimated the CMB variance from the three-year WMAP data, finding a lower value than expected from Gaussian simulations using the WMAP best-fit cosmological model. We repeat the analysis on the…

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

We describe the calibration and data processing methods used to generate full-sky maps of the cosmic microwave background (CMB) from the first year of Wilkinson Microwave Anisotropy Probe (WMAP) observations. Detailed limits on residual…