Related papers: Distinguishing standard reionization from dark mat…
We show that dark matter annihilation around the time of recombination can lead to growing ionization fraction perturbations, that track the linear collapse of matter over-densities. This amplifies small scale cosmological perturbations to…
With the imminent promise of constraints on the epoch of reionization from observations of microwave background anisotropies, the question of whether or not the standard Cold Dark Matter (CDM) model permits early reionization has been…
We study the anisotropy of the cosmic microwave background (CMB) in cold and mixed dark matter (CDM and MDM) models, with non scale-invariant primordial power spectra (i.e. $n \neq 1$) and a late, sudden reionization of the intergalactic…
We discuss the possibility to observe the products of dark matter annihilation that was going on in the early Universe. Of all the particles that could be generated by this process we consider only photons, as they are both uncharged and…
The first year Wilkinson Microwave Anisotropy Probe (WMAP) set quantitative constraints on the amplitude of any primordial non-Gaussianity. We run a series of dark matter-only N-body simulations with the WMAP constraints to investigate the…
We measure the angular power spectrum of the WMAP first-year temperature anisotropy maps. We use SpICE (Spatially Inhomogeneous Correlation Estimator) to estimate Cl's for multipoles l=2-900 from all possible cross-correlation channels.…
Updated constraints on dark matter cross section and mass are presented combining CMB power spectrum measurements from Planck, WMAP9, ACT, and SPT as well as several low-redshift datasets (BAO, HST, supernovae). For the CMB datasets, we…
We investigate the effect of Dark Stars (DSs) on the reionization history of the Universe, and the interplay between them and feedback due to Lyman-Werner (LW) radiation in reducing the Cosmic Microwave Background (CMB) optical depth to a…
We examine the constraints on high-redshift star formation, ultraviolet and X-ray pre-ionization, and the epoch of reionization at redshift z_r, inferred from the recent WMAP-5 measurement, tau_e = 0.084 +/- 0.016, of the electron…
Recent observations of the cosmic microwave background (CMB) anisotropies and the distribution of galaxies, galaxy clusters, and the Lyman Alpha forest have constrained the shape of the power spectrum of matter fluctuations on large scales…
We calculate the secondary anisotropies in the CMB produced by inhomogeneous reionization from simulations in which the effects of radiative and stellar feedback effects on galaxy formation have been included. This allows to…
The free-electron population during the reionized epoch rescatters CMB temperature quadrupole and generates a now well-known polarization signal at large angular scales. While this contribution has been detected in the…
Cosmic microwave background (CMB) radiation data obtained by different experiments contain, besides the desired signal, a superposition of microwave sky contributions. We present a fast and robust method, using a wavelet decomposition on…
A number of large current experiments aim to detect the signatures of the Cosmic Reionization at redshifts z>6. Their success depends crucially on understanding the character of the reionization process and its observable consequences and…
Spectroscopic studies of high-redshift objects and increasingly precise data on the cosmic microwave background (CMB) are beginning to independently place strong complementary bounds on the epoch of hydrogen reionization. Parameter…
We constrain the history of reionization using the data from Planck 2015 Cosmic Microwave Background (CMB) temperature and polarization anisotropy observations. We also use prior constraints on the reionization history at redshifts…
We study the constraints that future multifrequency Cosmic Microwave Background (CMB) experiments will be able to set on the metal enrichment history of the Inter Galactic Medium at the epoch of reionisation. We forecast the signal to noise…
We re-formulate cosmological perturbations in the decaying cold dark matter model, and calculate cosmological microwave background (CMB) anisotropies. By comparing our theoretical predictions with recent observational data from the…
The Wilkinson Microwave Anisotropy Probe (WMAP) science team has released results from the first year of operation at the Earth-Sun L2 Lagrange point. The maps are consistent with previous observations but have much better sensitivity and…
The James Webb Space Telescope (JWST) has observed massive galaxies at high redshifts, which implies an earlier epoch of reionization (EoR) compared with the cosmic microwave background (CMB) results. In this paper, based on \texttt{Planck…