Related papers: Correlation of Excursion Sets for Non-Gaussian CMB…
In this paper we demonstrate an efficient method for including both CMB temperature and polarisation data in optimal non-Gaussian estimators. The method relies on orthogonalising the multipoles of the temperature and polarisation maps and…
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 non-Gaussian CMB maps have been used as a…
We compute the three-point temperature correlation function of the COBE Differential Microwave Radiometer (DMR) two-year sky maps to search for evidence of non-Gaussian temperature fluctuations. We detect three-point correlations in our sky…
We consider a two-field model for inflation where the second order metric perturbations can be amplified by a parametric resonance during preheating. We demonstrate that there can arise a considerable enhancement of non-Gaussianity sourced…
The standard cosmological model predicts statistically isotropic cosmic microwave background (CMB) fluctuations characterized by the CMB temperature coefficients $a_{\ell m}$ being independent Gaussian random variables with zero mean and…
The decomposition of a signal on the sphere with the steerable wavelet constructed from the second Gaussian derivative gives access to the orientation, signed-intensity, and elongation of the signal's local features. In the present work,…
We present results from a test for the Gaussianity of the whole sky sub-degree scale CMB temperature anisotropy measured by the Wilkinson Microwave Anisotropy Probe (WMAP). We calculate the genus from the foreground-subtracted and…
Gaussianity of temperature fluctuations in the Cosmic Microwave Background(CMB) implies that the statistical properties of the temperature field can be completely characterized by its two point correlation function. The two point…
The fluctuations in the temperature and polarization of the cosmic microwave background are described by a hierarchy of Boltzmann equations. In its integral form, this Boltzmann hierarchy can be converted from the usual Fourier-space base…
The gaussian spread regression model for the calibration of site specific ensemble temperature forecasts depends on the apparently restrictive assumption that the uncertainty around temperature forecasts is normally distributed. We…
I present recent work aimed at showing how currently competing theories of the early universe leave their imprint on the temperature anisotropies of the CMB radiation. We consider the 3-point correlation function, as well as the inherent…
This work presents a reduced chi^2_nu test to search for non-gaussian signals in the CMBR TT power spectrum of recent CMBR data, WMAP, ACBAR and CBI data sets, assuming a mixed density field including adiabatic and isocurvature…
We study the cosmic microwave background (CMB) temperature fluctuations non-gaussianity due to the vector mode perturbations (Alfv\'en waves) supported by a stochastic cosmological magnetic field. We present detailed derivations of the…
Recent observations have indicated a Cosmic Microwave Background (CMB) temperature decrement in the direction of local galaxies within the 2MASS Redshift Survey. We investigate this detection by analyzing its frequency dependence and…
The issue of non-Gaussianity is not only related to distinguishing the theories of the origin of primordial fluctuations, but also crucial for the determination of cosmological parameters in the framework of inflation paradigm. We present…
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 amplitude of the primordial curvature…
Non-Gaussianity in the inflationary perturbations can couple observable scales to modes of much longer wavelength (even superhorizon), leaving as a signature a large-angle modulation of the observed cosmic microwave background (CMB) power…
[Abridged]: A detection or nondetection of primordial non-Gaussianity by using the CMB data is crucial not only to discriminate inflationary models but also to test alternative scenarios. Non-Gaussianity offers, therefore, a powerful probe…
We present an assessment of the CMB large scale anomalies in polarisation using the two-point correlation function as a test case. We employ the state of the art of large scale polarisation datasets: the first based on a Planck 2018 HFI 100…
We present a new method to compute the first crossing distribution in excursion set theory for the case of correlated random walks. We use a combination of the path integral formalism of Maggiore & Riotto, and the integral equation solution…