Spin Needlets for Cosmic Microwave Background Polarization Data Analysis (2008)
Geller, Daryl, Hansen, Frode K., Marinucci, Domenico, Kerkyacharian, Gerard, Picard, Dominique
Scalar wavelets have been used extensively in the analysis of Cosmic Microwave Background (CMB) temperature maps. Spin needlets are a new form of (spin) wavelets which were introduced in the...
Hikage, Chiaki, Matsubara, Takahiko, Coles, Peter, Liguori, Michele, Hansen, Frode K., Matarrese, Sabino
We present an analysis of the Minkowski Functionals (MFs) describing the WMAP three-year temperature maps to place limits on possible levels of primordial non-Gaussianity. In particular, we apply...
Yadav, Amit P. S., Komatsu, Eiichiro, Wandelt, Benjamin D., Liguori, Michele, Hansen, Frode K., Matarrese, Sabino
In our recent paper (Yadav et al. 2007) we described a fast cubic (bispectrum) estimator of the amplitude of primordial non-Gaussianity of local type, f_{NL}, from a combined analysis of the Cosmic...
Temperature and Polarization CMB Maps from Primordial non-Gaussianities of the Local Type (2007)
Liguori, Michele, Yadav, Amit, Hansen, Frode K., Komatsu, Eiichiro, Matarrese, Sabino, Wandelt, Benjamin
The forthcoming Planck experiment will provide high sensitivity polarization measurements that will allow us to further tighten the f_NL bounds from the temperature data. Monte Carlo simulations of...
Asymmetries in the local curvature of the WMAP data (2004)
Hansen, Frode K., Cabella, Paolo, Marinucci, Domenico, Vittorio, Nicola
We use the local curvature to investigate the possible existence of non-Gaussianity/asymmetry in the WMAP data. Considering the full sky we find results which are consistent with the Gaussian...
Hansen, Frode K., Marinucci, Domenico, Vittorio, Nicola
In (Hansen et al. 2002) we presented a new approach for measuring non-Gaussianity of the Cosmic Microwave Background (CMB) anisotropy pattern, based on the multivariate empirical distribution...
Fast CMB Power Spectrum Estimation of Temperature and Polarisation with Gabor Transforms (2002)
Hansen, Frode K., Gorski, Krzysztof M.
We extend the analysis of Gabor transforms on a Cosmic Microwave Background (CMB) temperature map (Hansen, Gorski and Hivon 2002) to polarisation. We study the temperature and polarisation power...
Gabor Transforms on the Sphere with Applications to CMB Power Spectrum Estimation (2002)
Hansen, Frode K., Gorski, Krzysztof M., Hivon, Eric
The Fourier transform of a dataset apodised with a window function is known as the Gabor transform. In this paper we extend the Gabor transform formalism to the sphere with the intention of applying...
Hansen, Frode K., Marinucci, Domenico, Natoli, Paolo, Vittorio, Nicola
We present a new, model-independent approach for measuring non-Gaussianity of the Cosmic Microwave Background (CMB) anisotropy pattern. Our approach is based on the empirical distribution function of...
Fast, exact CMB power spectrum estimation for a certain class of observational strategies (2001)
Wandelt, Benjamin D., Hansen, Frode K.
We describe a class of observational strategies for probing the anisotropies in the cosmic microwave background (CMB) where the instrument scans on rings which can be combined into an n-torus, the...
Gorski, Krzysztof M., Wandelt, Benjamin D., Hansen, Frode K., Hivon, Eric, Banday, Anthony J.
HEALPix is a Hierarchical, Equal Area, and iso-Latitude Pixelisation of the sphere designed to support efficiently - local operations on the pixel set, - a hierarchical tree structure for...
Hansen, Frode K., Lilje, Per B.
We deduce the equations that describe how polarized radiation is Comptonized by a hot electron gas. Low frequencies are considered, and the equations are expanded to second order in electron...