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Related papers: Observational constraints on the dark energy densi…

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Great uncertainty surrounds dark energy, both in terms of its physics, and the choice of methods by which the problem should be addressed. Here we quantify the redshift sensitivities offered by different techniques. We focus on the three…

Astrophysics · Physics 2009-11-11 Fergus Simpson , Sarah Bridle

In this work we have used the recent cosmic chronometers data along with the latest estimation of the local Hubble parameter value, $H_0$ at 2.4\% precision as well as the standard dark energy probes, such as the Supernovae Type Ia, baryon…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-02 Weiqiang Yang , Narayan Banerjee , Supriya Pan

We present cosmological perturbation theory in neutrino probe interacting dark-energy models, and calculate cosmic microwave background anisotropies and matter power spectrum. In these models, the evolution of the mass of neutrinos is…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yong-Yeon Keum

We use the radial baryon acoustic oscillation (BAO) measurements of Gaztanaga et al. (2008) to constrain parameters of dark energy models. These constraints are comparable with constraints from other "non-radial" BAO data. The radial BAO…

Astrophysics · Physics 2011-02-11 Lado Samushia , Bharat Ratra

Using the evolution history of the universe, one can make constraint on the parameter space of dynamic dark energy models. We discuss two different parameterized dark energy models. Our results further restrict the combined constraints…

Astrophysics · Physics 2009-11-13 Zhuo-Yi Huang , Bin Wang , Rong-Gen Cai , Ru-Keng Su

We present constraints on the mean matter density, Omega_m, the normalization of the density fluctuation power spectrum, sigma_8, and the dark-energy equation-of-state parameter, w, obtained from measurements of the X-ray luminosity…

Astrophysics · Physics 2010-02-03 A. Mantz , S. W. Allen , H. Ebeling , D. Rapetti

We use the angular power spectrum of the Cosmic Microwave Background, measured during the North American test flight of the BOOMERANG experiment, to constrain the geometry of the universe. Within the class of Cold Dark Matter models, we…

We examine the constraints that can be obtained on standard cold dark matter models from the most currently used data set: CMB anisotropies, type Ia supernovae and the SDSS luminous red galaxies. We also examine how these constraints are…

Astrophysics · Physics 2015-05-13 L. D. Ferramacho , A. Blanchard , Y. Zolnierowski

Recent attempts to fit Type Ia supernova data by modeling the dark energy density as a truncated Taylor series have suggested the possibility of metamorphosis, i.e., a rapidly evolving equation of state parameter, w_DE(z). However, we show…

Astrophysics · Physics 2009-11-10 J. Jonsson , A. Goobar , R. Amanullah , L. Bergstrom

In this paper, the holographic dark energy (HDE) model, where the future event horizon is taken as an IR cut-off, is confronted by using currently available cosmic observational data sets which include type Ia supernovae, baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-11 Lixin Xu

We present observational constraints on the nature of dark energy using the Supernova Legacy Survey three year sample (SNLS3) of Guy et al. (2010) and Conley et al. (2011). We use the 472 SNe Ia in this sample, accounting for recently…

In this work, we quantify the cosmological signatures of dark energy radiation -- a novel description of dark energy, which proposes that the dynamical component of dark energy is comprised of a thermal bath of relativistic particles…

High Energy Physics - Phenomenology · Physics 2024-03-27 Kim V. Berghaus , Tanvi Karwal , Vivian Miranda , Thejs Brinckmann

The use of Type Ia supernovae as calibrated standard candles is one of the most powerful tools to study the expansion history of the universe and thereby its energy components. While the analysis of some ~50 supernovae at redshifts around…

Astrophysics · Physics 2009-11-06 M. Goliath , R. Amanullah , P. Astier , A. Goobar , R. Pain

For two types of quintessence models having thawing and tracking properties, there exist analytic solutions for the dark energy equation of state w expressed in terms of several free parameters. We put observational bounds on the parameters…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-12 Takeshi Chiba , Antonio De Felice , Shinji Tsujikawa

It was hypothesized in the literature that some physical parameters may be time-evolving and the astrophysical data can serve as a probe. Recently, James Webb Space Telescope (JWST) have released its early observations. In this work, we…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-15 Ze-Fan Wang , Lei Lei , Lei Feng , Yi-Zhong Fan

We compute the cosmic microwave background bispectrum arising from the cross-correlation of primordial, lensing and Rees-Sciama signals. The amplitude of the bispectrum signal is sensitive to the matter density parameter, Omega_0, and the…

Astrophysics · Physics 2009-11-07 Licia Verde , David N. Spergel

We discuss bounds on the cosmological relativistic energy density as a function of redshift, reviewing the big bang nucleosynthesis and cosmic microwave background bounds, updating bounds from large scale structure, and introducing a new…

Astrophysics · Physics 2009-11-07 Andrew R. Zentner , Terry P. Walker

In this paper, we use the Type Ia supernova data as well as the CMB and LSS data to constrain the agegraphic dark energy model recently proposed by Cai. Due to its peculiar nature, the parameter $n$ of this model cannot be well constrained…

Astrophysics · Physics 2007-10-02 Xing Wu , Yi Zhang , Hui Li , Rong-Gen Cai , Zong-Hong Zhu

We apply the Bayesian concept of `evidence' to reveal systematically the nature of dark energy from present and future supernova luminosity distance measurements. We express the unknown dark energy equation of state w(z) as a low order…

Astrophysics · Physics 2008-11-26 T. D. Saini , J. Weller , S. L. Bridle

Dark energy affects the CMB through its perturbations and affects both CMB and Sn-Ia through its background evolution. Using recent CMB and Sn-Ia data sets, together with the most general parameterization of the dark energy equation of…