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Related papers: Measuring Cosmological Parameters with the JVAS an…

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We present constraints on the cosmological constant $\lambda_{0}$ from gravitational lensing statistics of the Jodrell Bank-VLA Astrometric Survey (JVAS). Although this is the largest gravitational lens survey which has been analysed,…

Astrophysics · Physics 2009-10-31 P. Helbig , D. R. Marlow , R. Quast , P. N. Wilkinson , I. W. A. Browne , L. V. E. Koopmans

The Cosmic Lens All-Sky Survey (CLASS) is an international collaborative program which has obtained high-resolution radio images of over 10000 flat-spectrum radio sources in order to create the largest and best studied statistical sample of…

We report the final results of the search for gravitationally lensed flat-spectrum radio sources found in the combination of CLASS (Cosmic Lens All Sky Survey) and JVAS (Jodrell-Bank VLA Astrometric Survey). VLA observations of 16,503…

The number of lenses found in the JVAS survey of flat-spectrum radio sources for gravitational lenses is consistent with statistical models of optical surveys for lensed quasars. The 90% confidence limit on Omega_0 in flat cosmological…

Astrophysics · Physics 2009-10-28 C. S. Kochanek

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 calculate the expected number of strongly lensed radio sources in a sample of 6500 sources observed with the Very Large Array as part of the Cosmic Lens All Sky Survey (CLASS) during the first two sessions of its observations. A…

Astrophysics · Physics 2011-05-23 Asantha R. Cooray

We present the selection of the Jodrell Bank Flat-spectrum (JBF) radio source sample, which is designed to reduce the uncertainties in the Cosmic Lens All-Sky Survey (CLASS) gravitational lensing statistics arising from the lack of…

Astrophysics · Physics 2008-11-26 J. P. McKean , I. W. A. Browne , N. J. Jackson , C. D. Fassnacht , P. Helbig

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 the strategy and status of a gravitational lens search for multiple imaging with angular separations between 6'' and 15'' with the combined JVAS and CLASS data set of ~15,000 flat-spectrum radio sources. Currently all but one…

Astrophysics · Physics 2007-05-23 P. M. Phillips , I. W. A. Browne , P. N. Wilkinson , N. J. Jackson

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…

Strong lensing has developed into an important astrophysical tool for probing both cosmology and galaxies (their structure, formation, and evolution). Using the gravitational lensing theory and cluster mass distribution model, we try to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Shuo Cao , Yu Pan , Marek Biesiada , Wlodzimierz Godlowski , Zong-Hong Zhu

We measure cosmological parameters using the three-dimensional power spectrum P(k) from over 200,000 galaxies in the Sloan Digital Sky Survey (SDSS) in combination with WMAP and other data. Our results are consistent with a ``vanilla'' flat…

We are conducting a redshift survey of 177 flat-spectrum radio sources in 3 samples covering the 5GHz flux ranges 50-100, 100-200 and 200-250 mJy. So far, we have measured 124 redshifts with completenesses of 80%, 68% and 58% for the…

Astrophysics · Physics 2009-10-30 E. E. Falco , C. S. Kochanek , J. M. Munoz

Galaxy-scale strong gravitational lenses with measured stellar velocity dispersions allow a test of the weak-field metric on kiloparsec scales and a geometric measurement of the cosmological distance-redshift relation, provided that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Josiah Schwab , Adam S. Bolton , Saul A. Rappaport

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

The third phase of the Cosmic Lens All-Sky Survey (CLASS) has recently been completed, bringing the total number of sources imaged to over 15000 in the CLASS and JVAS combined survey. In the VLA observations carried out in March and April…

The Cosmology Large Angular Scale Surveyor (CLASS) is an experiment to measure the signature of a gravita-tional-wave background from inflation in the polarization of the cosmic microwave background (CMB). CLASS is a multi-frequency array…

We present a forecast analysis on the feasibility of measuring the cosmological parameters with a large number of galaxy-galaxy scale strong gravitational lensing systems. Future wide area surveys are expected to discover and measure the…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-19 Tian Li , Thomas E. Collett , Coleman M. Krawczyk , Wolfgang Enzi

Several cosmological measurements have attained significant levels of maturity and accuracy over the last decade. Continuing this trend, future observations promise measurements of the statistics of the cosmic mass distribution at an…

Astrophysics · Physics 2008-11-26 Salman Habib , Katrin Heitmann , David Higdon , Charles Nakhleh , Brian Williams
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