English
Related papers

Related papers: Constraining non standard recombination: A worked …

200 papers

The formation of the cosmic microwave background radiation (CMBR) provides a very powerful probe of the early universe at the epoch of recombination. Specifically, it is possible to constrain the variation of fundamental physical constants…

Astrophysics · Physics 2009-10-31 Steen Hannestad

Data from the Atacama Cosmology Telescope (ACT) and the South Pole Telescope (SPT), combined with the nine-year data release from the WMAP satellite, provide very precise measurements of the cosmic microwave background (CMB) angular…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Micol Benetti , Martina Gerbino , William H. Kinney , Edward W. Kolb , Massimiliano Lattanzi , Alessandro Melchiorri , Luca Pagano , Antonio Riotto

We set new constraints on a seven-dimensional space of cosmological parameters within the class of inflationary adiabatic models. We use the angular power spectrum of the cosmic microwave background measured over a wide range of \ell in the…

An anisotropic measurement of the baryon acoustic oscillation (BAO) feature fixes the product of the Hubble constant and the acoustic scale $H_0 r_d$. Therefore, regardless of the dark energy dynamics, to accommodate a higher value of $H_0$…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Jarah Evslin , Anjan A Sen , Ruchika

The anisotropy of the cosmic microwave background radiation contains information about the contents and history of the universe. We report new limits on cosmological parameters derived from the angular power spectrum measured in the first…

We present cosmological parameters measurements from the full combination of DESI DR1 galaxy clustering data described with large-scale structure effective field theory. By incorporating additional datasets (photometric galaxies and CMB…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-23 Mikhail M. Ivanov , James M. Sullivan , Shi-Fan Chen , Anton Chudaykin , Mark Maus , Oliver H. E. Philcox

The perturbations in the electron number density during recombination contributes to the Cosmic Microwave Background bispectrum through second order terms. Perturbations in the electron density can be a factor of ~5 larger than the baryon…

Astrophysics · Physics 2010-04-21 Rishi Khatri , Benjamin D. Wandelt

The constraints on the time variation of the fine structure constant at recombination epoch relative to its present value, $\Delta\alpha/\alpha \equiv (\alpha_{\mathrm{rec}} - \alpha_{\mathrm{now}})/\alpha_{\mathrm{now}}$, are obtained from…

Astrophysics · Physics 2014-11-18 Masahiro Nakashima , Ryo Nagata , Jun'ichi Yokoyama

We analyze the spectrum of cosmic microwave background (CMB) anisotropies in the timescape cosmology: a potentially viable alternative to homogeneous isotropic cosmologies without dark energy. We exploit the fact that the timescape…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 M. Ahsan Nazer , David L. Wiltshire

Best-fit values of the spectral index of the curvature perturbation are presented, assuming the $\Lambda$CDM cosmology. Apart from the spectral index, the parameters are the Hubble parameter, the total matter density and the baryon density.…

Astrophysics · Physics 2016-08-30 L. Covi , D. H. Lyth

In this study, we use a sample of 130 well-localized fast radio bursts (FRBs) to constrain the physical baryon density $\Omega_{\rm b}h^2$, and the astrophysical contribution from host galaxies. The cosmological dependence entering the…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-05 Lázaro L. Sales , Klecio E. L. de Farias , Amilcar R. Queiroz , Rafael A. Batista , Bruno W. Ribeiro , Raiff H. Santos

Calculations of cosmological hydrogen recombination are vital for the extraction of cosmological parameters from cosmic microwave background (CMB) observations, and for imposing constraints to inflation and re-ionization. The Planck}…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-22 Daniel Grin , Christopher M. Hirata

Cosmological models and their parameters are widely debated, especially about whether the current discrepancy between the values of the Hubble constant, $H_{0}$, obtained by type Ia supernovae (SNe Ia), and the Planck data from the Cosmic…

CMB observables have largely fixed the expansion history of the universe in the deceleration regime and provided two self-calibrated absolute standards for dark energy studies: the sound horizon at recombination as a standard ruler and the…

Astrophysics · Physics 2011-05-12 Wayne Hu

We place constraints on the number of relativistic degrees of freedom and on the baryon asymmetry at the epoch of Big Bang Nucleosynthesis (BBN) and at recombination, using cosmic background radiation (CBR) data from the Wilkinson Microwave…

High Energy Physics - Phenomenology · Physics 2008-11-26 V. Barger , James P. Kneller , Hye-Sung Lee , Danny Marfatia , Gary Steigman

In universes with significant curvature or cosmological constant, cosmic microwave background (CMB) anisotropies are created very recently via the Rees-Sciama or integrated Sachs-Wolfe effects. This causes the CMB anisotropies to become…

Astrophysics · Physics 2009-10-30 S. P. Boughn , R. G. Crittenden , N. G. Turok

Measurements of Baryonic Acoustic Oscillations in galaxy surveys have been recognized as a powerful tool for constraining dark energy. However, this method relies on the knowledge of the size of the acoustic horizon at recombination derived…

I show that neutral lithium couples strongly to the cosmic microwave background (CMB) through its 6708A resonant transition after it recombines at z~500. At observed wavelengths of <335 micron, the CMB anisotropies are significantly altered…

Astrophysics · Physics 2009-11-06 Abraham Loeb

Goodness-of-fit statistics are used to quantitatively establish the compatibility of CMB anisotropy predictions in a wide range of DMR-normalized, open and spatially-flat $\Lambda$, CDM cosmogonies with the set of all presently available…

Astrophysics · Physics 2009-10-28 Ken Ganga , Bharat Ratra , Naoshi Sugiyama

We use a compilation of cosmic microwave anisotropy data to constrain the epoch of reionization in the Universe, as a function of cosmological parameters. We consider spatially-flat cosmologies, varying the matter density $\Omega_0$ (the…

Astrophysics · Physics 2009-10-31 Louise M Griffiths , Domingos Barbosa , Andrew R Liddle