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Related papers: Beyond optical depth: Future determination of ioni…

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In light of the recent inference of a high optical depth to Thomson scattering, tau, from the WMAP data we investigate the effects of extended periods of partial ionization and ask if the value of tau inferred by assuming a single sharp…

Astrophysics · Physics 2009-06-15 Gilbert Holder , Zoltan Haiman , Manoj Kaplinghat , Lloyd Knox

We study CMB secondary anisotropies produced by inhomogeneous reionization by means of cosmological simulations coupled with the radiative transfer code CRASH. The reionization history is consistent with the WMAP Thomson optical depth…

Astrophysics · Physics 2009-11-10 R. Salvaterra , B. Ciardi , A. Ferrara , C. Baccigalupi

Reionization of the cosmic neutral hydrogen by the first stars in the Universe is an inhomogeneous process which produces spatial fluctuations in free electron density. These fluctuations lead to observable signatures in cosmological probes…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-11 Sourabh Paul , Suvodip Mukherjee , Tirthankar Roy Choudhury

Details of how the primordial plasma recombined and how the universe later reionized are currently somewhat uncertain. This uncertainty can restrict the accuracy of cosmological parameter measurements from the Cosmic Microwave Background…

Astrophysics · Physics 2008-11-26 Antony Lewis , Jochen Weller , Richard Battye

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…

Astrophysics · Physics 2009-11-13 J. Michael Shull , Aparna Venkatesan

Neutral hydrogen around high-z QSO and an optical depth tau ~ 0.17 can be reconciled if reionization is more complex than a single transition at z ~ 6-8. Tracing its details could shed a new light on the first sources of radiation. Here we…

The cosmic microwave background (CMB) anisotropies have turned out to represent one of the most stringent 'bottle necks' for scenarios of large scale structure formation. As a possibility to relax this constraint, it has been proposed that…

Astrophysics · Physics 2009-10-22 Ruth Durrer

The epoch of the end of reionization and the Thomson optical depth to the cosmic microwave background depend on the power spectrum amplitude on small scales and on the ionizing photon emissivity per unit mass in collapsed halos. In this…

Astrophysics · Physics 2007-05-23 L. A. Popa

Upcoming cosmic microwave background (CMB) experiments will measure temperature fluctuations on small angular scales with unprecedented precision. Small-scale CMB fluctuations are a mixture of late-time effects: gravitational lensing,…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Kendrick M. Smith , Simone Ferraro

We present measurements of large-scale cosmic microwave background (CMB) E-mode polarization from the Cosmology Large Angular Scale Surveyor (CLASS) 90 GHz data. Using 115 det-yr of observations collected through 2024 with a variable-delay…

We report a measurement of the E-mode polarization power spectrum of the cosmic microwave background (CMB) using 150 GHz data taken from July 2014 to December 2016 with the POLARBEAR experiment. We reach an effective polarization map noise…

We derive updated Cosmic Microwave Background (CMB) constraints on annihilating dark matter, and present forecasts for upcoming CMB surveys. We show that the addition of recent temperature, polarization, and lensing data from ground-based…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-12 Charlotte Myers , Dominic Agius , Daniele Gaggero , Angelo Ricciardone

We review the observable consequences of the epoch of reionization (EoR) on the cosmic microwave background (CMB), and the resulting constraints on the EoR. We discuss how Thomson scattering with the free electrons produced during EoR…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Christian L. Reichardt

We present an approximate, analytical calculation of the reionized spectra $C_l^{XX}$ of cosmic microwave background radiation (CMB) anisotropies and polarizations generated by relic gravitational waves (RGWs). Three simple models of…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 T. Y. Xia , Y. Zhang

We present constraints on the patchy reionization by measuring the trispectrum of the Planck 2015 cosmic microwave background (CMB) temperature anisotropies. The patchy reionization leads to anisotropies in the CMB optical depth, and the…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-14 Toshiya Namikawa

We show that by jointly fitting cosmic microwave background (CMB) and astrophysical data - a compilation of UV luminosity data from the Hubble Frontier Field and neutral hydrogen data from distant sources-, we can infer on the shape of the…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-16 Daniela Paoletti , Dhiraj Kumar Hazra , Fabio Finelli , George F. Smoot

The WMAP first year detection of a high redshift reionization through its imprints on CMB anisotropy T and TE mode angular power spectra calls for a better comprehension of the universe ionization and thermal history after the standard…

Astrophysics · Physics 2007-05-23 C. Burigana , L. A. Popa , F. Finelli , R. Salvaterra , G. De Zotti , N. Mandolesi

One of the main goals of modern cosmic microwave background (CMB) missions is to measure the tensor-to-scalar ratio $r$ accurately to constrain inflation models. Due to ignorance about the reionization history $X_{e}(z)$, this analysis is…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-03 King Lau , Jiayu Tang , M. -C. Chu

We investigate the impact of spatial variations in the ionized fraction during reionization on temperature anisotropies in the CMB. We combine simulations of large scale structure to describe the underlying density field with an analytic…

Astrophysics · Physics 2009-11-10 Oliver Zahn , Matias Zaldarriaga , Lars Hernquist , Matthew McQuinn

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…

Astrophysics · Physics 2009-11-10 Asantha Cooray