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In this paper, we study the cosmological implications of the 100 square degree Weak Lensing survey (the CFHTLS-Wide, RCS, VIRMOS-DESCART and GaBoDS surveys). We combine these weak lensing data with the cosmic microwave background (CMB)…

Astrophysics · Physics 2010-05-07 Hong Li , Jie Liu , Jun-Qing Xia , Lei Sun , Zu-Hui Fan , Charling Tao , Andre Tilquin , Xinmin Zhang

We investigate observational constraints from lensing statistics and high-z type Ia supernovae on flat cosmological models with nonrelativistic matter and an exotic fluid with equation of state, $p_x=(m/3 -1)\rho_x$. We show that agreement…

Astrophysics · Physics 2008-11-26 Ioav Waga , Ana Paula M. R. Miceli

In this paper, we use quasars calibrated from type Ia supernova (SN Ia) to constrain cosmological models. We consider three different X-ray luminosity ($L_{X}$) - ultraviolet luminosity ($L_{UV}$) relations of quasars, i.e., the standard…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-14 Haixiang Zhang , Yang Liu , Hongwei Yu , Xiaodong Nong , Nan Liang , Puxun Wu

In this manuscript, we investigate the constraints on dynamical vacuum models within the framework of $\Lambda(t)$CDM cosmology by assuming a parameterization of the vacuum energy density as $\rho_{\Lambda}(t)=\rho_{\Lambda 0} \left[1 +…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-14 Yerlan Myrzakulov , M. Koussour , M. Bulanbay , S. Muminov , J. Rayimbaev

Because the baryon-to-photon ratio eta_{10} is in some doubt, we drop nucleosynthetic constraints on eta_{10} and fit the three cosmological parameters (h, Omega_M, eta_{10}) to four observational constraints: Hubble parameter h_o =…

Astrophysics · Physics 2009-10-30 G. Steigman , N. Hata , J. E. Felten

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

We perform a detailed confrontation of various oscillating dark-energy parame-trizations with the latest sets of observational data. In particular, we use data from Joint Light Curve analysis (JLA) sample from Supernoave Type Ia, Baryon…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Supriya Pan , Emmanuel N. Saridakis , Weiqiang Yang

We present a study of the baryonic fraction in galaxy clusters aimed at constraining the cosmological parameters Omega_m, Omega_Lambda and the ratio between the pressure and density of the ``dark'' energy, w. We use results on the…

Astrophysics · Physics 2008-11-26 S. Ettori , P. Tozzi , P. Rosati

We report measurements of the mass density, Omega_M, and cosmological-constant energy density, Omega_Lambda, of the universe based on the analysis of 42 Type Ia supernovae discovered by the Supernova Cosmology Project. The…

We present constraints on the cosmological constant lambda_0 and the density parameter Omega_0 from joint constraints from the analyses of gravitational lensing statistics of the Jodrell Bank-VLA Astrometric Survey (JVAS), optical…

Astrophysics · Physics 2007-05-23 J. F. Macias-Perez , P. Helbig , R. Quast , A. Wilkinson , R. D. Davies

The possibility of determining cosmological parameters on the basis of a wide set of observational data including the Abell-ACO cluster power spectrum and mass function, peculiar velocities of galaxies, the distribution of Ly-$\alpha$…

Astrophysics · Physics 2007-05-23 B. Novosyadlyj , R. Durrer , S. Gottloeber , V. N. Lukash , S. Apunevych

We present a tomographic cosmic shear study from the Deep Lens Survey (DLS), which, providing a limiting magnitude r_{lim}~27 (5 sigma), is designed as a pre-cursor Large Synoptic Survey Telescope (LSST) survey with an emphasis on depth.…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-22 M. James Jee , J. Anthony Tyson , Stefan Hilbert , Michael D. Schneider , Samuel Schmidt , David Wittman

I review the basic theory of the cosmic microwave background anisotropies in adiabatic cold dark matter cosmologies. The latest observational results on the CMB power spectrum are consistent with the simplest inflationary models and…

Astrophysics · Physics 2009-09-25 G. Efstathiou

Cosmological constraints are usually derived under the assumption of a $6$ parameters $\Lambda$-CDM theoretical framework or simple one-parameter extensions. In this paper we present, for the first time, cosmological constraints in a…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-30 Eleonora Di Valentino , Alessandro Melchiorri , Joseph Silk

We illustrate how recently improved low-redshift cosmological measurements can tighten constraints on neutrino properties. In particular we examine the impact of the assumed cosmological model on the constraints. We first consider the new…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-14 Beth A. Reid , Licia Verde , Raul Jimenez , Olga Mena

We investigate observational constraints from present and future supernova data on a large class of decaying vacuum cosmologies. In such scenarios the present value of the vacuum energy density is quantified by a positive $\beta$ parameter…

Astrophysics · Physics 2009-11-07 J. S. Alcaniz , J. M. F. Maia

In this paper, we combine the latest observational data, including the WMAP five-year data (WMAP5), BOOMERanG, CBI, VSA, ACBAR, as well as the Baryon Acoustic Oscillations (BAO) and Type Ia Supernoave (SN) "Union" compilation (307 sample)…

Astrophysics · Physics 2008-11-26 Jun-Qing Xia , Hong Li , Gong-Bo Zhao , Xinmin Zhang

We use a combination of the most recent cosmic microwave background (CMB) flat -band power measurements to place constraints on Hubble's constant h and the total density of the Universe Omega_o in the context of inflation-based cold dark…

Astrophysics · Physics 2009-10-30 Charles H. Lineweaver , Domingos Barbosa

The observational data on the large scale structure (LSS) of the Universe are used to determine cosmological parameters within the class of adiabatic inflationary models. We show that a mixed dark matter model with cosmological constant…

Astrophysics · Physics 2007-05-23 B. Novosyadlyj , R. Durrer , S. Apunevych

We show how estimates of parameters characterizing inflation-based theories of structure formation localized over the past year when large scale structure (LSS) information from galaxy and cluster surveys was combined with the rapidly…