S. Matarrese

The pre-launch Planck Sky Model: a model of sky emission at submillimetre to centimetre wavelengths

We present the Planck Sky Model (PSM), a parametric model for generating all-sky, few arcminute resolution maps of sky emission at submillimetre to centimetre wavelengths, in both intensity and polarisation. Several options are implemented to model the cosmic microwave background, Galactic diffuse emission (synchrotron, free-free, thermal and spinning dust, CO lines), Galactic HII regions, extragalactic radio sources, dusty galaxies, and thermal and kinetic Sunyaev-Zeldovich signals from clusters of galaxies. Each component is simulated by means of educated interpolations/extrapolations of data sets available at the time of the launch of the Planck mission, complemented by state-of-the-art models of the emission. Distinctive features of the simulations are spatially varying spectral properties of synchrotron and dust; different spectral parameters for each point source; modelling of the clustering properties of extragalactic sources and of the power spectrum of fluctuations in the cosmic infrared background. The PSM enables the production of random realisations of the sky emission, constrained to match observational data within their uncertainties. It is implemented in a software package that is regularly updated with incoming information from observations. The model is expected to serve as a useful tool for optimising planned microwave and sub-millimetre surveys and testing data processing and analysis pipelines. It is, in particular, used to develop and validate data analysis pipelines within the Planck collaboration. A version of the software that can be used for simulating the observations for a variety of experiments is made available on a dedicated website.

The potential of X‐ray cluster surveys to constrain primordial non‐Gaussianity

We present forecasts for constraints on deviations from Gaussian distribution of primordial density perturbations from future high‐sensitivity X‐ray surveys of galaxy clusters. Our analysis is based on computing the Fisher‐Matrix for number counts and large-scale power spectrum of clusters. The surveys that we consider have high‐sensitivity and wide‐area to detect about 2: 5�10 5 extended sources, and to provide reliable measurements of robust mass proxies for about 2�10 4 clusters. Based on the so-called self-calibration approac h, and including Planck priors in our analysis, we constrain at once nine cosmological parameters and four nuisance parameters, which define the relation between cluster mass and X‐ray flux. Because of the scale dependence of large‐scale bias induced by local‐shape non‐Gaussianity, we find that the power spectrum provides strong constraints on the non‐Gaussianity fNL parameter, which complement the stringent constraints on the power spectrum normalization,� 8, from the number counts. To quantify the joint constraints on the two parameters,� 8 and fNL, that specify the timing of structure formation for a fixed background expa nsion, we define the figure-of� � :

Low- frequency gravitational waves from cosmological compact binaries

We consider gravitational waves emitted by various populations of compact binaries at cosmological distances. We use population synthesis models to characterize the properties of double neutron stars, double black holes and double white dwarf binaries as well as white dwarf-neutron star, white dwarf-black hole and black hole-neutron star systems. We use the observationally determined cosmic star formation history to reconstruct the redshift distribution of these sources and their merging rate evolution. The gravitational signals emitted by each source during its early-inspiral phase add randomly to produce a stochastic background in the low frequency band with spectral strain amplitude between ∼ 10 Hz and ∼ 5 × 10 Hz at frequencies in the interval [∼ 5 × 10 − 5 × 10] Hz. The overall signal which, at frequencies above 10 Hz, is largely dominated by double white dwarf systems, might be detectable with LISA in the frequency range [1− 10] mHz and acts like a confusion limited noise component which might limit the LISA sensitivity at frequencies above 1 mHz.

Primordial non-Gaussianity: local curvature method and statistical significance of constraints on fNL from WMAP data

We test the consistency of estimates of the non-linear coupling constant f

The integrated bispectrum as a test of cosmic microwave background non-Gaussianity: detection power and limits on fNL with WMAP data

_{NL

Wilkinson Microwave Anisotropy Probe 5-yr constraints on fnl with wavelets

using non-Gaussian cosmic microwave background (CMB) maps generated by the method described in the work of Liguori, Matarrese \amp Moscardini. This procedure to obtain non-Gaussian maps differs significantly from the method used in previous works on the estimation of f

WMAP 5-year constraints on fnl with wavelets

_NL

The correlation function of X-ray galaxy clusters in the ROSAT All-Sky Survey 1 Bright Sample

. Nevertheless, using spherical wavelets, we find results in very good agreement with Mukherjee \amp Wang, showing that the two ways of generating primordial non-Gaussian maps give equivalent results. Moreover, we introduce a new method for estimating the non-linear coupling constant from CMB observations by using the local curvature of the temperature fluctuation field. We present both Bayesian credible regions (assuming a flat prior) and proper (frequentist) confidence intervals on f

Constraints on the non-linear coupling parameter fnl with the Archeops data

_NL

A numerical study of the effects of primordial non-Gaussianities on weak lensing statistics

, and discuss the relation between the two approaches. The Bayesian approach tends to yield lower error bars than the frequentist approach, suggesting that a careful analysis of the different interpretations is needed. Using this method, we estimate f