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New results on the anisotropy of the cosmic microwave background (CMB) and its polarization based on the first 3 years of data from the Wilkinson Microwave Anisotropy Probe (WMAP) have revised the electron scattering optical depth downward…

Astrophysics · Physics 2009-11-11 Marcelo A. Alvarez , Paul R. Shapiro , Kyungjin Ahn , Ilian T. Iliev

The cosmic microwave background (CMB) polarisation and the 21 cm line fluctuations are powerful probes of cosmological reionisation. We study how the cross-correlation between the CMB polarisation (E-modes) and the 21 cm line fluctuations…

Astrophysics · Physics 2009-04-17 Hiroyuki Tashiro , Nabila Aghanim , Mathieu Langer , Marian Douspis , Saleem Zaroubi

We show that the epoch(s) of reionization when the ionization fraction of the universe is about half can be determined by correlating Cosmic Microwave Background (CMB) temperature maps with 21-cm line maps at degree scales ($l\sim 100$).…

Astrophysics · Physics 2009-11-13 Marcelo A. Alvarez , Eiichiro Komatsu , Olivier Doré , Paul R. Shapiro

Recently, it was pointed out that invoking a large value of the CMB optical depth, $\tau_{\rm CMB} = 0.09$, could help resolve tensions between DESI DR2 BAO data and the CMB. This is larger than the value of $\tau_{\rm CMB} = 0.058$…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-23 Christopher Cain , Alexander Van Engelen , Kevin S. Croker , Darby Kramer , Anson D'Aloisio , Garett Lopez

Hydrogen atoms in the Universe that initially formed at redshift z = 1100 were reionized at 5 < z < 60. It is likely that this transition proceeded through a mixed phase of partial ionization. We develop an analytic approach to calculating…

Astrophysics · Physics 2009-10-30 Lloyd Knox , Roman Scoccimarro , Scott Dodelson

The cosmic microwave background (CMB) polarization, whose experimental detection must become the next natural step in the study of the CMB radiation, depends on the dynamics of hydrogen recombination in the Universe, on the relation between…

Astrophysics · Physics 2007-05-23 M. V. Sazhin , A. V. Toporensky

The patchiness in the reionization process alters the statistics of Cosmic Microwave Background (CMB), with the kinematic Sunyaev-Zeldovich (kSZ) effect in the CMB temperature power spectrum being a notable consequence. In this work, we aim…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-13 Divesh Jain , Tirthankar Roy Choudhury , Srinivasan Raghunathan , Suvodip Mukherjee

The Epoch of Reionization (EoR) depends on the complex astrophysics governing the birth and evolution of the first galaxies and structures in the intergalactic medium. EoR models rely on cosmic microwave background (CMB) observations, and…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-30 Yuxiang Qin , Vivian Poulin , Andrei Mesinger , Bradley Greig , Steven Murray , Jaehong Park

A detection of excess cosmic microwave background (CMB) B-mode polarization on large scales allows the possibility of measuring not only the amplitude of these fluctuations but also their scale dependence, which can be parametrized as the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-06 Gabrielle Simard , Duncan Hanson , Gil Holder

We calculate the cosmic microwave background (CMB) bispectrum due to inhomogeneous reionization. We calculate all the terms that can contribute to the bispectrum that are products of first order terms on all scales in conformal Newtonian…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Rishi Khatri , Benjamin D. Wandelt

The CMB polarization is the Everest in the quest to characterize the earliest photons from the Universe. After a long list of ever-decreasing upper limits, a detection of polarization was made in 2002 by the DASI team at ell =~ 500. The…

Instrumentation and Methods for Astrophysics · Physics 2024-11-28 Denis Barkats

At the epoch of reionization, when the high-redshift inter-galactic medium (IGM) is being enriched with metals, the 63.2 micron fine structure line of OI is pumped by the ~ 1300 AA soft UV background and introduces a spectral distortion in…

Astrophysics · Physics 2009-11-13 Carlos Hernandez-Monteagudo , Zoltan Haiman , Licia Verde , Raul Jimenez

The thermodynamic and dynamical properties of a variable dark energy model with density scaling as rho_x \propto (1+z)^m, z being the redshift, are discussed following the outline of Jetzer et al. This kind of models are proven to lead to…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-08 Philippe Jetzer , Crescenzo Tortora

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…

Astrophysics · Physics 2009-10-31 M. Bruscoli , A. Ferrara , R. Fabbri , B. Ciardi

Current cosmological constraints from Cosmic Microwave Background (CMB) anisotropies are typically derived assuming a standard recombination scheme, however additional resonance and ionizing radiation sources can delay recombination,…

Astrophysics · Physics 2009-02-23 Silvia Galli , Rachel Bean , Alessandro Melchiorri , Joseph Silk

As a result of our limited data on reionization, the total optical depth for electron scattering, $\tau$, limits precision measurements of cosmological parameters from the Cosmic Microwave Background (CMB). It was recently shown that the…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-27 Anastasia Fialkov , Abraham Loeb

Cosmic microwave background (CMB) experiments that constrain the tensor-to-scalar ratio $r$ are now approaching the sensitivity at which delensing---removing the $B$ modes induced by the gravitational lensing of large-scale structure---is…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-23 Kirit S. Karkare

The polarization of the Cosmic Microwave Background (CMB) radiation carries essential information on early stages of the Universe such as the cosmic inflation, forming cosmological structures through gravitational lensing, and the epoch of…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-22 E. Carretti , C. Baccigalupi

The intergalactic helium became fully ionized by the end of cosmic noon ($z\sim2$). Similarly to the reionization of hydrogen, helium reionization is expected to be patchy, driven by luminous quasars that ionize the intergalactic gas in…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-14 Mesut Çalışkan , Neha Anil Kumar , Selim C. Hotinli , Marc Kamionkowski

We compute cosmic microwave background (CMB) anisotropy constraints on exotic forms of energy injection in electromagnetic (e.m.) channels over a large range of timescales. These constraints are very powerful around or just after…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-28 Vivian Poulin , Julien Lesgourgues , Pasquale D. Serpico
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