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We cross-correlate the third-year WMAP data with galaxy samples extracted from the SDSS DR4 (SDSS4) covering 13% of the sky, increasing by a factor of 3.7 the volume sampled in previous analyses. The new measurements confirm a positive cross-correlation with higher significance (total signal-to-noise of about 4.7). The correlation as a function of angular scale is well fitted by the integrated Sachs-Wolfe (ISW) effect for LCDM flat FRW models with a cosmological constant. The combined analysis of different samples gives Omega_L=0.80-0.85$ (68% Confidence Level, CL) or $0.77-0.86$ (95% CL). We find similar best fit values for Omega_L for different galaxy samples with median redshifts of z ~0.3 and z ~0.5, indicating that the data scale with redshift as predicted by the LCDM cosmology (with equation of state parameter w=-1). This agreement is not trivial, but can not yet be used to break the degeneracy constraints in the w versus Omega_L plane using only the ISW data.
We present constraints on extensions of the minimal cosmological models dominated by dark matter and dark energy, $Lambda$CDM and $w$CDM, by using a combined analysis of galaxy clustering and weak gravitational lensing from the first-year data of the
We use numerical simulations to characterize the performance of a clustering-based method to calibrate photometric redshift biases. In particular, we cross-correlate the weak lensing (WL) source galaxies from the Dark Energy Survey Year 1 (DES Y1) sa
We present galaxy-galaxy lensing measurements from 1321 sq. deg. of the Dark Energy Survey (DES) Year 1 (Y1) data. The lens sample consists of a selection of 660,000 red galaxies with high-precision photometric redshifts, known as redMaGiC, split int
The gravitational-wave event GW170817, together with the electromagnetic counterpart, shows that the speed of tensor perturbations $c_T$ on the cosmological background is very close to that of light $c$ for the redshift $z<0.009$. In generalized Proc
We cross-correlate galaxy weak lensing measurements from the Dark Energy Survey (DES) year-one (Y1) data with a cosmic microwave background (CMB) weak lensing map derived from South Pole Telescope (SPT) and Planck data, with an effective overlapping