Michele Liguori

Impact of the 1/f noise and the asymmetric beam on non-Gaussianity searches with Planck (2009)

Donzelli, Simona, Hansen, Frode K., Liguori, Michele, Maino, Davide

We study the impact of correlated instrumental noise and non-circular antenna beam patterns on primordial non-Gaussianity analysis. The two systematic effects are reproduced in the case of the Planck...

Directional Variations of the Non-Gaussianity Parameter f_NL (2009)

Rudjord, Øystein, Hansen, Frode K., Lan, Xiaohong, Liguori, Michele, Marinucci, Domenico, Matarrese, Sabino

We investigate local variations of the primordial non-Gaussianity parameter f_NL in the WMAP data, looking for possible influence of foreground contamination in the full-sky estimate of f_NL. We...

Constraining Running Non-Gaussianity (2009)

Sefusatti, Emiliano, Liguori, Michele, Yadav, Amit P. S., Jackson, Mark G., Pajer, Enrico

The primordial non-Gaussian parameter fNL has been shown to be scale-dependent in several models of inflation with a variable speed of sound. Starting from a simple ansatz for a scale-dependent...

CMB lensing and primordial non-Gaussianity (2009)

Hanson, Duncan, Smith, Kendrick M., Challinor, Anthony, Liguori, Michele

We study the effects of gravitational lensing on the estimation of non-Gaussianity from the bispectrum of the cosmic microwave background (CMB) temperature anisotropies. We find that the effect of...

An Estimate of the Primordial Non-Gaussianity Parameter f_NL Using the Needlet Bispectrum from WMAP (2009)

Rudjord, Oystein, Hansen, Frode K., Lan, Xiaohong, Liguori, Michele, Marinucci, Domenico, Matarrese, Sabino

We use the full bispectrum of spherical needlets applied to the WMAP data of the cosmic microwave background as an estimator for the primordial non-Gaussianity parameter f_NL. We use needlet scales...

CMBPol Mission Concept Study: Probing Inflation with CMB Polarization (2008)

Baumann, Daniel, Jackson, Mark G, Adshead, Peter, Amblard, Alexandre, Ashoorioon, Amjad, Bartolo, Nicola, ...

We summarize the utility of precise cosmic microwave background (CMB) polarization measurements as probes of the physics of inflation. We focus on the prospects for using CMB measurements to...

CMBPol Mission Concept Study: Probing Inflation with CMB Polarization (2008)

Baumann, Daniel, Jackson, Mark G., Adshead, Peter, Amblard, Alexandre, Ashoorioon, Amjad, Bartolo, Nicola, ...

We summarize the utility of precise cosmic microwave background (CMB) polarization measurements as probes of the physics of inflation. We focus on the prospects for using CMB measurements to...

Weighing the spatial and temporal fluctuations of the dark universe (2008)

Zhang, Pengjie, Bean, Rachel, Liguori, Michele, Dodelson, Scott

A generic prediction of the standard cosmology, based on general relativity (GR), dark matter and the cosmological constant (and more generally, smooth dark energy), is that, the two gravitational...

Limits on Primordial Non-Gaussianity from Minkowski Functionals of the WMAP Temperature Anisotropies (2008)

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...

Fast Estimator of Primordial Non-Gaussianity from Temperature and Polarization Anisotropies in the Cosmic Microwave Background II: Partial Sky Coverage and Inhomogeneous Noise (2007)

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...

Galaxy-CMB Cross-Correlation as a Probe of Alternative Models of Gravity (2007)

Schmidt, Fabian, Liguori, Michele, Dodelson, Scott

Bekenstein's alternative to general relativity, TeVeS, reduces to Modified Newtonian Dynamics (MOND) in the galactic limit. On cosmological scales, the (potential well overdensity) relationship is...

Matching WMAP 3-yrs results with the Cosmological Slingshot Primordial Spectrum (2007)

Germani, Cristiano, Liguori, Michele

We consider a recently proposed scenario for the generation of primordial cosmological perturbations, the so called Cosmological Slingshot scenario. We firstly obtain a general expression for the...

A discriminating probe of gravity at cosmological scales (2007)

Zhang, Pengjie, Liguori, Michele, Bean, Rachel, Dodelson, Scott

The standard cosmological model is based on general relativity and includes dark matter and dark energy. An important prediction of this model is a fixed relationship between the gravitational...

Can Cosmic Structure form without Dark Matter? (2006)

Dodelson, Scott, Liguori, Michele

One of the prime pieces of evidence for dark matter is the observation of large overdense regions in the universe. Since we know from the cosmic microwave background that the regions that contained...

CMB lensing extraction and primordial non-Gaussianity (2004)

Lesgourgues, Julien, Liguori, Michele, Matarrese, Sabino, Riotto, Antonio

The next generation of CMB experiments should get a better handle on cosmological parameters by mapping the weak lensing deflection field, which is separable from primary anisotropies thanks to the...

High-Resolution Simulations of Cosmic Microwave Background non-Gaussian Maps in Spherical Coordinates (2003)

Liguori, Michele, Matarrese, Sabino, Moscardini, Lauro

We describe a new numerical algorithm to obtain high-resolution simulated maps of the Cosmic Microwave Background (CMB), for a broad class of non-Gaussian models. The kind of non-Gaussianity we...