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Given the recent detection of gravitational waves from individual sources, it is almost a certainty that some form of background of gravitational waves will be detected in future. The most promising candidate for such a detection is backgrounds made up of incoherent superposition of the signal of unresolved astrophysical, or backgrounds sourced by earlier cosmological events. Such backgrounds will also contain anisotropies about an average value. The information contained in the background level and any anisotropies will be extremely valuable as an astrophysical and cosmological probe. As such, the ability to reconstruct sky maps of the signal will become important as the sensitivity increases. We build and test a pixel-based, maximum-likelihood gravitational wave background (GWB) map-maker that uses the cross-correlation of sets of generalized baselines as input. The resulting maps are a representation of the GWB power, or strain 'intensity' on the sky. We test the algorithm by reconstructing known input maps with different baseline configurations. We also apply the map-maker to a subset of the Advanced Laser Interferometer Gravitational Wave observatory data. [ABSTRACT FROM AUTHOR]

ABSTRACT The upcoming generation of cosmic microwave background experiments face a major challenge in detecting the weak cosmic B-mode signature predicted as a product of primordial gravitational waves. To achieve the required sensitivity these experiments must have impressive control of systematic effects and detailed understanding of the foreground emission that will influence the signal. In this paper, we present templates of the intensity and polarization of emission from one of the main Galactic foregrounds, interstellar dust. These are produced using a model which includes a three-dimensional description of the Galactic magnetic field, examining both large and small scales. We also include in the model the details of the dust density, grain alignment and the intrinsic polarization of the emission from an individual grain. We present here Stokes parameter template maps at 150 GHz and provide an online repository () for these and additional maps at frequencies that will be targeted by upcoming experiments such as EBEX, Spider and SPTpol. [ABSTRACT FROM AUTHOR]

We develop the XF cosmic microwave background (CMB) temperature and polarization anisotropy power spectrum and likelihood technique for the Planck CMB satellite mission. We give an overview of this estimator and its current implementation, and present the results of applying this algorithm to simulated Planck data. We show that it can accurately extract the power spectrum of Planck data for the high-ℓ multipoles range. We compare the XF approximation for the likelihood to other high-ℓ likelihood approximations such as Gaussian and Offset Lognormal and a low-ℓ pixel-based likelihood. We show that the XF likelihood is not only accurate at high ℓ, but also performs well at moderately low multipoles. We also present results for cosmological parameter Markov chain Monte Carlo estimation with the XF likelihood. As long as the low-ℓ polarization and temperature power are properly accounted for, e.g. by adding an adequate low-ℓ likelihood ingredient, the input parameters are recovered to a high level of accuracy. [ABSTRACT FROM AUTHOR]

We use Minkowski functionals (MFs) to constrain a primordial non-Gaussian contribution to the cosmic microwave background intensity field as observed in the 150- and 145-GHz BOOMERanG maps from the 1998 and 2003 flights, respectively, performing for the first time a joint analysis of the two data sets. A perturbative expansion of the MF formulae in the limit of a weakly non-Gaussian field yields analytical formulae, derived by Hikage et al., which can be used to constrain the coupling parameter f without the need for non-Gaussian simulations. We find at 95 per cent CL, significantly improving the previous constraints by De Troia et al. on the BOOMERanG 2003 data set. These are the best f limits to date for suborbital probes. [ABSTRACT FROM AUTHOR]

ABSTRACT The trispectrum of the cosmic microwave background can be used to assess the level of non-Gaussianity on cosmological scales. It probes the fourth-order moment, as a function of angular scale, of the probability distribution function of fluctuations and has been shown to be sensitive to primordial non-Gaussianity, secondary anisotropies (such as the Ostriker–Vishniac effect) and systematic effects (such as astrophysical foregrounds). In this paper we develop a formalism for estimating the trispectrum from high-resolution sky maps that incorporates the impact of finite sky coverage. This leads to a series of operations applied to the data set to minimize the effects of contamination due to the Gaussian component and correlations between estimates at different scales. To illustrate the effect of the estimation process, we apply our procedure to the BOOMERanG data set and show that it is consistent with Gaussianity. This work presents the first estimation of the cosmic microwave background trispectrum on subdegree scales. [ABSTRACT FROM AUTHOR]

An abstract of the article "Myocardial fibrosis assessed by integrated back scatter is related to diastolic function and major cardiac arrhythmias in hypertrophic cardiomyopathy," by M. A. Losi and colleagues is presented.

An abstract of the article "Determinants of left atrial dilation in patients with hypertrophic cardiomyopathy," by M. A. Losi and colleagues is presented.