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Related papers: The effect of reionization on the COBE normalizati…

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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 three papers summarize the methods employed by the COBE-DMR group to analyze the power spectrum of the two-year DMR anisotropy maps. Results for the slope and normalization of the power spectrum are presented and compared. The…

Astrophysics · Physics 2007-05-23 K. Gorski , C. L. Bennett , A. J. Banday

Many analyses of microwave background experiments neglect the correlation of noise in different frequency or polarization channels. We show that these correlations, should they be present, can lead to severe misinterpretation of an…

Astrophysics · Physics 2009-10-22 Scott Dodelson , Arthur Kosowsky , Steven T. Myers

Much recent work on the cosmic microwave background (CMB) has focussed on the angular power spectrum of temperature anisotropies and particularly on the recovery of cosmological parameters from acoustic peaks in the power spectrum. However,…

Astrophysics · Physics 2007-05-23 Marc Kamionkowski

We study the effects due to mismatches in passbands, polarization angles, and temperature and polarization calibrations in the context of the upcoming cosmic microwave background experiment Simons Observatory (SO). Using the SO…

The anisotropy and polarization of the cosmic microwave background radiation (CMBR) induced by the scalar and tensor metric perturbations are computed in the long-wavelength limit. It is found that the large-scale polarization of CMBR…

Astrophysics · Physics 2009-10-22 Ka Lok Ng , Kin-Wang Ng

The reionization of the Universe is expected to leave a signal in the form of a sharp step in the spectrum of the sky. If reionization occurs at 5 < z < 20, a feature should appear in the radio sky at 70 - 240 MHz due to redshifted HI 21-cm…

Astrophysics · Physics 2007-05-23 P. A. Shaver , R. A. Windhorst , P. Madau , A. G. de Bruyn

Gravitational lensing distorts the cosmic microwave background (CMB) anisotropies and imprints a characteristic pattern onto it. The distortions depend on the projected matter density between today and redshift $z \sim 1100$. In this paper…

Astrophysics · Physics 2016-08-25 Matias Zaldarriaga , Uros Seljak

The reionisation of the intergalactic medium (IGM) was driven by the first stars, galaxies, and accreting black holes. However, the relative importance of these sources and the efficiency by which ionising photons escape into the IGM remain…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-18 Timo P. Schwandt , Ivelin Georgiev , Sambit K. Giri , Garrelt Mellema , Ilian T. Iliev

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

I review recent progress towards a detailed understanding of the power spectrum of cosmic string perturbations induced on the Microwave Background (CMB). The use of a simple analytic model allows to include important effects that have not…

Astrophysics · Physics 2007-05-23 Leandros Perivolaropoulos

We point out that if quantum field renormalization is taken into account the predictions of slow-roll inflation for both the scalar and tensorial power spectra change significantly for wavelengths that today are at observable scales

Cosmology and Nongalactic Astrophysics · Physics 2010-05-18 Ivan Agullo , Jose Navarro-Salas , Gonzalo J. Olmo , Leonard Parker

Beam asymmetries result in statistically-anisotropic cosmic microwave background (CMB) maps. Typically, they are studied for their effects on the CMB power spectrum, however they more closely mimic anisotropic effects such as gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-05 Duncan Hanson , Antony Lewis , Anthony Challinor

We generate simulations of the CMB temperature field as observed by the WMAP satellite, taking into account the detailed shape of the asymmetric beams and scanning strategy of the experiment, and use these to re-estimate the WMAP beam…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-02 Ingunn Kathrine Wehus , Lotty Ackerman , H. K. Eriksen , Nicolaas E. Groeneboom

We generalize previous work on early photoionization to CDM models with Omega<1. Such models have received recent interest because the excess power in the large-scale galaxy distribution is phenomenologically fit if the ``shape parameter"…

Astrophysics · Physics 2009-10-07 Max Tegmark , Joseph Silk

Anisotropies of the cosmic microwave background (CMB) have proven to be a very powerful tool to constrain dark matter annihilation at the epoch of recombination. However, CMB constraints are currently derived using a number of reasonable…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Silvia Galli , Tracy R. Slatyer , Marcos Valdes , Fabio Iocco

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

We explore the impact of the reionization history on examining the shape of the power spectrum of the primordial gravitational waves (PGWs) with the cosmic microwave background (CMB) polarization. The large-scale CMB generated from the…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-02 Hanchun Jiang , Toshiya Namikawa

We explore the evolution of the flux power spectrum in the Cosmic Reionization On Computers (CROC) simulations. We find that, contrary to some previous studies, the shape of the flux power spectrum is rather insensitive to the timing of…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-13 Nishant Mishra , Nickolay Gnedin

We discuss the evolution of linear perturbations in a quintessence model in which the scalar field is non-minimally coupled to cold dark matter. We consider the effects of this coupling on both cosmic microwave background temperature…

Astrophysics · Physics 2009-02-18 Seokcheon Lee , Guo-Chin Liu , Kin-Wang Ng
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