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Related papers: Supersonic baryon-CDM velocities and CMB B-mode po…

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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…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-14 Cora Dvorkin , Kfir Blum , Matias Zaldarriaga

It is known that in contrast with the E-mode polarization, the B-mode polarization of the Cosmic Microwave Background cannot be generated by the Compton scattering in the case of scalar mode of metric perturbation. However it is possible to…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-29 Rohoollah Mohammadi , Jafar Khodagholizadeh , Mahdi Sadegh , She-Sheng Xue

We study the signal from patchy reionization in view of the future high accuracy polarization measurements of the Cosmic Microwave Background (CMB). We implement an extraction procedure of the patchy reionization signal analogous to CMB…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-18 Anirban Roy , Andrea Lapi , David Spergel , Carlo Baccigalupi

Reionization, the only phase transition in the Universe since recombination, is a key event in the cosmic history of baryonic matter. We derive, in the context of the large-scale bias expansion, the imprints of the epoch of reionization in…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-08 Fabian Schmidt , Florian Beutler

We present a new and especially powerful signature of cosmic strings and other topological or non-topological defects in the polarization of the cosmic microwave background (CMB). We show that even if defects contribute 1% or less in the…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Juan Garcia-Bellido , Ruth Durrer , Elisa Fenu , Daniel G. Figueroa , Martin Kunz

We study the effect on the cosmic microwave background (CMB) anisotropy and large scale structure (LSS) power spectrum of a scattering interaction between cold dark matter and baryons. This scattering alters the CMB anisotropy and LSS…

Astrophysics · Physics 2009-11-07 Xuelei Chen , Steen Hannestad , Robert J. Scherrer

We present and compare several cosmological constraints on the cross section for elastic scattering between dark matter (DM) and baryons, for cross sections with a range of power-law dependences on the DM-baryon relative velocity $v$,…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-18 Tracy R. Slatyer , Chih-Liang Wu

The damping of primordial perturbations at small scales gives rise to distortions of the cosmic microwave background (CMB). Here, the dependence of the distortion on the different types of cosmological initial conditions is explored,…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-18 Jens Chluba , Daniel Grin

Previous works have demonstrated that the generation of secondary CMB anisotropies due to the molecular optical depth is likely too small to be observed. In this paper, we examine additional ways in which primordial chemistry and the dark…

The effect of weak gravitational lensing on the cosmic microwave background (CMB) temperature anisotropies and polarization will provide access to cosmological information that cannot be obtained from the primary anisotropies alone. We…

Astrophysics · Physics 2007-05-23 Sarah Smith , Anthony Challinor , Graca Rocha

We investigate a high-$z$ cosmological model to compute the co-moving sound horizon $r_s$ at baryon-velocity freeze-out towards the end of hydrogen recombination. This model assumes a replacement of the conventional CMB photon gas by…

General Physics · Physics 2017-05-30 Steffen Hahn , Ralf Hofmann

Cosmological models predict transfer functions by which primordial density perturbations develop into CMB anisotropy and Large-Scale Structure. We use the current set of observations to reconstruct the primordial power spectrum for standard…

Astrophysics · Physics 2007-05-23 Eric Gawiser

We investigate the possible effects of reionization by active sources on the cosmic microwave background. We concentrate on the sources themselves as the origin of reionization, rather than early object formation, introducing an extra…

Astrophysics · Physics 2010-04-08 Jochen Weller , Richard A. Battye , Andreas Albrecht

During the transition from a neutral to a fully reionized universe, scattering of cosmic microwave background (CMB) photons via free-electrons leads to a new anisotropy contribution to the temperature distribution. If the reionization…

Astrophysics · Physics 2009-11-10 Asantha Cooray

Big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) anisotropies independently predict the universal baryon density. Comparing their predictions will provide a fundamental test on cosmology. Using BBN and the CMB…

Astrophysics · Physics 2009-11-07 Richard H. Cyburt

The formation of the first stars is an exciting frontier area in astronomy. Early redshifts z ~ 20 have become observationally promising as a result of a recently recognized effect of a supersonic relative velocity between the dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-31 Anastasia Fialkov , Rennan Barkana , Eli Visbal , Dmitriy Tseliakhovich , Christopher M. Hirata

We identify high density regions of supercluster size in high resolution N-body simulations of a representative volume of three Cold Dark Matter Universes. By assuming that (1) the density and peculiar velocities of baryons trace those of…

Astrophysics · Physics 2009-10-31 Antonaldo Diaferio , Rashid A. Sunyaev , Adi Nusser

We study the degree to which the cosmic microwave background (CMB) can be used to constrain primordial non-Gaussianity involving one tensor and two scalar fluctuations, focusing on the correlation of one polarization $B$ mode with two…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 P. Daniel Meerburg , Joel Meyers , Alex van Engelen , Yacine Ali-Haïmoud

We compute the imprints left on the CMB by two cosmic reionization models consistent with current observations but characterized by alternative radiative feedback prescriptions (suppression and filtering) resulting in a different…

Astrophysics · Physics 2015-05-13 C. Burigana , L. A. Popa , R. Salvaterra , R. Schneider , T. Roy Choudhury , A. Ferrara

It is well known that annihilations in the homogeneous fluid of dark matter (DM) can leave imprints in the cosmic microwave background (CMB) anisotropy power spectrum. However, the relevance of DM annihilations in halos for cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-20 Vivian Poulin , Pasquale D. Serpico , Julien Lesgourgues
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