English
Related papers

Related papers: How well do we understand cosmological recombinati…

200 papers

We study the formation of first molecules, negative Hydrogen ions and molecular ions in model of the Universe with cosmological constant and cold dark matter. The cosmological recombination is described in the framework of modified model of…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-14 B. Novosyadlyj , O. Sergijenko , V. M. Shulga

Primordial magnetic fields (PMFs) may explain observations of magnetic fields on extragalactic scales. They are most cleanly constrained by measurements of cosmic microwave background radiation (CMB) anisotropies. Their effects on cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-18 Karsten Jedamzik , Tom Abel , Yacine Ali-Haimoud

The recombination clumping factor, $C$, is a key parameter in modeling cosmic reionization, but its value is sensitive to the definition of the Intergalactic Medium (IGM). We investigate the clumping factor using the GAMER adaptive mesh…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-13 Yuri Oku , Renyue Cen

Cosmological hydrogen recombination has recently been the subject of renewed attention because of its importance for predicting the power spectrum of cosmic microwave background anisotropies. It has become clear that it is necessary to…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-21 Yacine Ali-Haïmoud , Christopher M. Hirata

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

21cm emission from residual neutral hydrogen after the epoch of reionization can be used to trace the cosmological power spectrum of density fluctuations. Using a Fisher matrix formulation, we provide a detailed forecast of the constraints…

Astrophysics · Physics 2009-11-13 Eli Visbal , Abraham Loeb , Stuart Wyithe

CMBR distortion concerned with recombination of the primordial plasma is calculated in frequency band from 1 GHz to 100 GHz in the frame of the standard cosmological model for different values of cosmological density parameters:…

Astrophysics · Physics 2007-05-23 E. E. Kholupenko , A. V. Ivanchik , D. A. Varshalovich

The physical ingredients to describe the epoch of cosmological recombination are amazingly simple and well-understood. This fact allows us to take into account a very large variety of physical processes, still finding potentially measurable…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 R. A. Sunyaev , J. Chluba

We explore the imprint of the cosmological hydrogen recombination lines on the power spectrum of the cosmic microwave background (CMB). In particular, we focus our analysis in the three strongest lines for the Balmer, Paschen and Brackett…

Astrophysics · Physics 2009-11-10 J. A. Rubino-Martin , C. Hernandez-Monteagudo , R. A. Sunyaev

By depleting the ionizing photon budget available to expand cosmic HII regions, recombining systems (or Lyman limit systems) can have a large impact during (and following) cosmic reionization. Unfortunately, directly resolving such…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Emanuele Sobacchi , Andrei Mesinger

We present the new recombination code HYREC-2, holding the same accuracy as the state-of-the-art codes HYREC and COSMOREC and, at the same time, surpassing the computational speed of the code RECFAST commonly used for CMB-anisotropy data…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-22 Nanoom Lee , Yacine Ali-Haïmoud

We examine cosmic microwave background constraints on variations in the recombination history of the universe. We use a very general extension to the standard model of recombination characterized by two parameters, a and b, which multiply…

Astrophysics · Physics 2007-05-23 Angela M. Linn , Robert J. Scherrer

The recombination of hydrogen and helium at z~1000-7000 gives unavoidable distortions to the Cosmic Microwave Background (CMB) spectrum. We present a detailed calculation of the line intensities arising from the Ly-alpha (2p-1s) and…

Astrophysics · Physics 2009-11-13 Wan Yan Wong , Sara Seager , Douglas Scott

The main goal of this work is to calculate the contributions to the cosmological recombination spectrum due to bound-bound transitions of helium. We show that due to the presence of helium in the early Universe unique features appear in the…

Astrophysics · Physics 2009-11-13 J. A. Rubino-Martin , J. Chluba , R. A. Sunyaev

The recent EDGES measurements of the global 21-cm signal from the cosmic dawn suggest that the kinetic temperature of the inter-galactic medium (IGM) might be significantly lower compared to its expected value. The colder IGM directly…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-02 Kanan K. Datta , Aritra Kundu , Ankit Paul , Ankita Bera

Measurements of the Hubble parameter from the distance ladder are in tension with indirect measurements based on the cosmic microwave background (CMB) data and the inverse distance ladder measurements at 3-4 $\sigma$ level. We consider…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-12 Chi-Ting Chiang , Anže Slosar

There is growing interest in using 3-dimensional neutral hydrogen mapping with the redshifted 21 cm line as a cosmological probe, as it has been argued to have a greater long-term potential than the cosmic microwave background. However, its…

Astrophysics · Physics 2008-11-26 Yi Mao , Max Tegmark , Matthew McQuinn , Matias Zaldarriaga , Oliver Zahn

With the recent measurement of full sky cosmic microwave background polarization from WMAP, key cosmological degeneracies have been broken, allowing tighter constraints to be placed on cosmological parameters inferred assuming a standard…

Astrophysics · Physics 2008-11-26 Rachel Bean , Alessandro Melchiorri , Joe Silk

The inconsistent Hubble constant values derived from cosmic microwave background (CMB) observations and from local distance-ladder measurements may suggest new physics beyond the standard $\Lambda$CDM paradigm. It has been found in earlier…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-12 Miaoxin Liu , Zhiqi Huang , Xiaolin Luo , Haitao Miao , Naveen K. Singh , Lu Huang

The atomic recombination process leads to a softening of the matter equation of state as reflected by a reduced generalized adiabatic index, with accompanying heat release. We study the effects of this recombination softening and reheating…

Astrophysics · Physics 2009-08-20 Po Kin Leung , Chi-Wang Chan , Ming-Chung Chu