Mapping gravitational lensing of the CMB using local likelihoods

Abstract

We present a new estimation method for mapping the gravitational lensing potential from observed CMB intensity and polarization fields. Our method uses Bayesian techniques to estimate the average curvature of the potential over small local regions. These local curvatures are then used to construct an estimate of a low pass filter of the gravitational potential. By utilizing Bayesian/likelihood methods one can easily overcome problems with missing and/or non-uniform pixels and problems with partial sky observations (E and B mode mixing, for example). Moreover, our methods are local in nature which allow us to easily model spatially varying beams and are highly parallelizable. We note that our estimates do not rely on the typical Taylor approximation which is used to construct estimates of the gravitational potential by Fourier coupling. We present our methodology with a flat sky simulation under nearly ideal experimental conditions with a noise level of 1 $\mu K$-arcmin for the temperature field, $\sqrt{2}$ $\mu K$-arcmin for the polarization fields, with an instrumental beam full width at half maximum (FWHM) of 0.25 arcmin.

References in corpus (19)

• Efficient Computation of CMB anisotropies in closed FRW models
• Statistics of Cosmic Microwave Background Polarization
• Mass Reconstruction with CMB Polarization
• CMB Lensing Reconstruction on the Full Sky
• Weak Lensing of the CMB: A Harmonic Approach
• Detection of Gravitational Lensing in the Cosmic Microwave Background
• Reconstruction of lensing from the cosmic microwave background polarization
• A limit on the detectability of the energy scale of inflation
• Gravitational lensing as a contaminant of the gravity wave signal in CMB
• Separation of Gravitational-Wave and Cosmic-Shear Contributions to Cosmic Microwave Background Polarization
• Determining Neutrino Mass from the CMB Alone
• Correlation of CMB with large-scale structure: II. Weak lensing
• Reconstructing Projected Matter Density from Cosmic Microwave Background
• Mapping the Dark Matter through the CMB Damping Tail
• Analyzing weak lensing of the cosmic microwave background using the likelihood function
• Measuring Dark Matter Power Spectrum from Cosmic Microwave Background
• Cosmological Information from Lensed CMB Power Spectra
• Lensing effect on polarization in microwave background: extracting convergence power spectrum
• Real space estimator for the weak lensing convergence from the CMB

Cited by in corpus (7)

• A measurement of gravitational lensing of the microwave background using South Pole Telescope data
• Maximum a posteriori CMB lensing reconstruction
• CMB Delensing Beyond the B Modes
• Full-sky lensing reconstruction of gradient and curl modes from CMB maps
• Weak lensing of the Lyman-alpha forest
• Approximate Likelihood Approaches for Detecting the Influence of Primordial Gravitational Waves in Cosmic Microwave Background Polarization
• Shrinking the Quadratic Estimator