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Related papers: Constraints on a quintessence model from gravitati…

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We investigate the evolution of matter density perturbations and some properties of the peculiar velocity field for a special class of exponential potentials in a scalar field model for quintessence, for which a general exact solution is…

Astrophysics · Physics 2008-11-26 Claudio Rubano , Mauro Sereno

We use the statistics of strong gravitational lensing based on the Cosmic Lens All-Sky Survey (CLASS) data to constrain cosmological parameters in a spatially-flat, inverse power-law potential energy density, scalar-field dark energy…

Astrophysics · Physics 2009-11-10 Kyu-Hyun Chae , Gang Chen , Bharat Ratra , Dong-Wook Lee

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

We reanalyse optical gravitational lens surveys from the literature in order to determine relative probabilities in the $\lambda_{0}$-$\Omega_{0}$ plane, using a softened singular isothermal sphere lens model. In addition, we examine a…

Astrophysics · Physics 2007-05-23 Ralf Quast , Phillip Helbig

I review simultaneous constraints on the cosmological parameters lambda_0 and Omega_0 from gravitational lensing. The emphasis is on systematic extragalactic surveys for strong gravitational lenses, mainly the largest and best-defined such…

Astrophysics · Physics 2007-05-23 Phillip Helbig

We derive constraints on cosmological parameters and the properties of the lensing galaxies from gravitational lens statistics based on the final Cosmic Lens All Sky Survey (CLASS) data. For a flat universe with a classical cosmological…

By using the comoving distance, we derive an analytic expression for the optical depth of gravitational lensing, which depends on the redshift to the source and the cosmological model characterized by the cosmic mass density parameter…

Astrophysics · Physics 2008-11-26 Zong-Hong Zhu

By comparing the results of numerical microlensing simulations to the observed long-term variability of quasars, strong upper limits on the cosmological density of compact objects in the mass range 0.01 to 0.0001 solar masses may be…

Astrophysics · Physics 2009-11-07 E. Zackrisson , N. Bergvall , P. Helbig

We explore the implications of gravitationally lensed QSOs and high-redshift SNe Ia observations for spatially flat cosmological models in which a classically evolving scalar field currently dominates the energy density of the Universe. We…

Astrophysics · Physics 2009-10-31 Ioav Waga , Joshua A. Frieman

We study the effect of the cosmological constant on the statistical properties of gravitational lenses in flat cosmologies (Omega_{0}+lambda_{0} = 1). It is shown that some of the lens observables are strongly affected by the cosmological…

Astrophysics · Physics 2009-10-30 Deepak Jain , N. Panchapakesan , S. Mahajan , V. B. Bhatia

We present new limits on cosmological parameters from the statistics of gravitational lensing, based on the recently revised knowledge of the luminosity function and internal dynamics of E/S0 galaxies that are essential in lensing…

Astrophysics · Physics 2009-10-30 Masashi Chiba , Yuzuru Yoshii

We use current observations on the number statistics of gravitationally lensed optical arcs towards galaxy clusters to derive an upper limit on the cosmological mass density of the Universe. The gravitational lensing statistics due to…

Astrophysics · Physics 2009-10-31 Asantha R. Cooray

We study observational constraints on cosmological models with a quintessence arising from moduli fields. The scalar field potential is given by a double exponential potential V=V_0 exp(-A e^{sqrt{2} kappa phi}). After reviewing the…

Astrophysics · Physics 2009-10-31 S. C. C. Ng

I present constraints on cosmological parameters in the lambda_0-Omega_0 plane from a joint analysis of gravitational lensing statistics (astro-ph/9904175) and the magnitude-redshift relation for Type Ia supernovae (astro-ph/9812133 and…

Astrophysics · Physics 2007-05-23 Phillip Helbig

We re-analyze constraints on the cosmological constant that can be obtained by examining the statistics of strong gravitational lensing of distant quasars by intervening galaxies, focusing on uncertainties in galaxy models (including…

Astrophysics · Physics 2007-05-23 Yu-Chung N. Cheng , Lawrence M. Krauss

In this paper, observational constraints on the cosmic equation of state of dark energy ($p = w \rho$) have been investigated using gravitational lensing statistics. A likelihood analysis of the lens surveys has been carried out to…

Astrophysics · Physics 2009-09-25 Abha Dev , Deepak Jain , N. Panchapakesan , S. Mahajan , V. B. Bhatia

The large-scale dynamics of matter is inferred from the observed peculiar velocities of galaxies via the POTENT procedure. The smoothed fields of velocity and mass-density fluctuations are recovered from the current data of about 3000…

Astrophysics · Physics 2007-05-23 Avishai Dekel

We present a detailed strong lensing analysis of an HST/ACS legacy dataset for the first gravitational lens, Q0957+561. With deep imaging we identify 24 new strongly lensed features, which we use to constrain mass models. We model the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Ross Fadely , Charles R. Keeton , Reiko Nakajima , Gary M. Bernstein

Upcoming ground and space based observatories such as the DES, the LSST, the JDEM concepts and the SKA, promise to dramatically increase the size of strong gravitational lens samples. A significant fraction of the systems are expected to be…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Benjamin M. Dobke , Lindsay J. King , Christopher D. Fassnacht , Matthew W. Auger

We combine the Cosmic Lens All-Sky Survey (CLASS) with new Sloan Digital Sky Survey (SDSS) data on the local velocity dispersion distribution function of E/S0 galaxies, $\phi(\sigma)$, to derive lens statistics constraints on…

Astrophysics · Physics 2011-05-12 J. L. Mitchell , C. R. Keeton , J. A Frieman , R. K. Sheth
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