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We explore the constraints on the history of reionization from Planck 2015 Cosmic Microwave Background (CMB) data and we derive the forecasts for future CMB observations. We consider a class of monotonic histories of reionization as…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Dhiraj Kumar Hazra , Daniela Paoletti , Fabio Finelli , George F. Smoot

Cosmic background radiation, both diffuse and discrete in nature, produced at different cosmic epochs before and after recombination, provides key information on the evolution of cosmic structures. We discuss the main classes of sources…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-24 Carlo Burigana , Tiziana Trombetti , Matteo Bonato , Adélie Gorce , Luigi Toffolatti

The standard interpretation of the observed redshifted spectra and luminosities towards distant astrophysical objects is that the universe is expanding, an inference which is found to be consistent with other cosmological probes as well.…

General Physics · Physics 2013-08-06 Meir Shimon

A new parametrization of the reionization history is presented to facilitate robust comparisons between different observations and with theory. The evolution of the ionization fraction with redshift can be effectively captured by specifying…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Hy Trac

We review the current state of empirical knowledge of the total budget of baryonic matter in the Universe as observed since the epoch of reionization. Our summary examines on three milestone redshifts since the reionization of H in the IGM,…

Astrophysics · Physics 2015-05-13 Jason X. Prochaska , Jason Tumlinson

Cosmology in general, and relation between redshift and cosmic epoch in particular, is usually obscure to first years university students, secondary students, as well as journalists, politicians and the general public scientists may have…

Physics Education · Physics 2024-01-10 Hervé Dole

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

The contribution of stars in galaxies to cosmic reionisation depends on the star formation history in the Universe, the abundance of galaxies during reionisation, the escape fraction of ionising photons and the clumping factor of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jan-Pieter Paardekooper , Sadegh Khochfar , Claudio Dalla Vecchia

Observation of the redshifted 21-cm signal from Cosmic Dawn and Epoch of Reionization is a challenging endeavor in observational cosmology. Presence of orders of magnitude brighter astrophysical foregrounds and various instrumental…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-03 Aishrila Mazumder , Abhirup Datta , Arnab Chakraborty , Suman Majumdar

The standard model of cosmology is investigated using time dependent cosmological constant $\Lambda$ and Newton's gravitational constant $G$. The total energy content is described by the modified Chaplygin gas equation of state. It is found…

General Relativity and Quantum Cosmology · Physics 2009-03-12 Mubasher Jamil , Farook Rahaman , Mehedi Kalam

We examine the possibility of constraining the cosmological mean mass and dark energy densities by an application of the Alcock-Paczynski test on redshifted 21-cm maps of the epoch of reionization. The 21-cm data will be provided as a…

Astrophysics · Physics 2009-11-10 Adi Nusser

We present a method of calibrating the properties of photometric redshift bins as part of a larger Markov Chain Monte Carlo (MCMC) analysis for the inference of cosmological parameters. The redshift bins are characterised by their mean and…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-02 Michael McLeod , Sreekumar T. Balan , Filipe B. Abdalla

In recent years the possibility of measuring the temporal change of radial and transverse position of sources in the sky in real time have become conceivable thanks to the thoroughly improved technique applied to new astrometric and…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-26 Claudia Quercellini , Luca Amendola , Amedeo Balbi , Paolo Cabella , Miguel Quartin

We propose a phenomenological unified model for dark matter and dark energy based on an equation of state parameter $w$ that scales with the $\arctan$ of the redshift. The free parameters of the model are three constants: $\Omega_{b0}$,…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-17 R. R. Cuzinatto , L. G. Medeiros , E. M. de Morais

We revisit the epoch of cosmic speed-up characterized by the redshift of transition from a decelerated to an accelerated phase. This redshift is termed the transition redshift ($z_t$). We use the spatially Flat and Non-Flat variants of the…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-02 David Dahiya , Deepak Jain

During cosmic reionization, the 21-cm brightness fluctuations were highly non-Gaussian, and complementary statistics can be extracted from the distribution of pixel brightness temperatures that are not derivable from the 21-cm power…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-27 Tony Pan , Rennan Barkana

Time is a parameter playing a central role in our most fundamental modeling of natural laws. Relativity theory shows that the comparison of times measured by different clocks depends on their relative motions and on the strength of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-11 Pierre Magain , Clémentine Hauret

Degeneracies among parameters of the cosmological model are known to drastically limit the information contained in the matter distribution. In the first paper of this series, we shown that the cosmic web environments; namely the voids,…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-21 Tony Bonnaire , Joseph Kuruvilla , Nabila Aghanim , Aurélien Decelle

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

We use cosmography to present constraints on the kinematics of the Universe, without postulating any underlying theoretical model. To this end, we use a Monte Carlo Markov Chain analysis to perform comparisons to the supernova Ia Union 2…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Alejandro Aviles , Christine Gruber , Orlando Luongo , Hernando Quevedo