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Related papers: The 2dF gravitational lens survey

200 papers

The 2dF Galaxy Redshift Survey is the first to measure more than 100,000 redshifts. This allows precise measurements of many of the key statistical measures of galaxy clustering, in particular redshift-space distortions and the large-scale…

Astrophysics · Physics 2009-11-06 J. A. Peacock , the 2dFGRS Team

Gravitational lensing provides a means to measure mass that does not rely on detecting and analysing light from the lens itself. Compact objects are ideal gravitational lenses, because they have relatively large masses and are dim. In this…

Instrumentation and Methods for Astrophysics · Physics 2017-06-15 A. J. Harding , R. Di Stefano , S. Lépine , J. Urama , D. Pham , C. Baker

We present a description of the observations and data reduction procedures for an extensive spectroscopic and multi-band photometric study of nine high redshift, optically-selected cluster candidates. The primary goal of the survey is to…

Astrophysics · Physics 2009-10-30 J. B. Oke , Marc Postman , Lori Lubin

We report the discovery of the two-image gravitationally lensed quasar SDSS J1335+0118. The object was selected as a lens candidate from the Sloan Digital Sky Survey. The imaging and spectroscopic follow-up observations confirm that the…

Strong gravitational lenses are a rare and instructive type of astronomical object. Identification has long relied on serendipity, but different strategies -- such as mixed spectroscopy of multiple galaxies along the line of sight, machine…

We have analyzed images from the VST ATLAS survey to identify candidate gravitationally lensed quasar systems in a sample of WISE sources with W1 - W2 > 0.7. Results from followup spectroscopy with the Baade 6.5 m telescope are presented…

Astrophysics of Galaxies · Physics 2017-04-26 Paul L. Schechter , Nicholas D. Morgan , B. Chehade , N. Metcalfe , T. Shanks , Michael McDonald

We investigate the dependence of galaxy clustering on luminosity and spectral type using the 2dF Galaxy Redshift Survey (2dFGRS). Spectral types are assigned using the principal component analysis of Madgwick et al. We divide the sample…

We present a new sample of galaxy-scale strong gravitational-lens candidates, selected from 904 square degrees of Data Release 4 of the Kilo-Degree Survey (KiDS), i.e., the "Lenses in the Kilo-Degree Survey" (LinKS) sample. We apply two…

This project is a visual search for field dwarf galaxies using Second Palomar Sky Survey photographic plates. A morphologically selected sample of 310 objects yielded 145 detections of true dwarfs within a redshift search window of 0 to…

Astrophysics · Physics 2009-10-28 James Schombert , Rachel Pildis , Jo Ann Eder

With today's millimeter and submillimeter instruments observers use gravitational lensing mostly as a tool to boost the sensitivity when observing distant objects. This is evident through the dominance of gravitationally lensed objects…

Astrophysics · Physics 2007-05-23 Tommy Wiklind , Danielle Alloin

The gravitational lens configuration where a background galaxy is closely aligned with a foreground galaxy, can provide accurate measurement of the dark matter density profile in the foreground galaxy, free of dynamical assumptions.…

Astrophysics · Physics 2009-11-11 J. P. Willis , P. C. Hewett , S. J. Warren

The DENIS survey is currently imaging the entire southern sky in the I, J, and K wavebands. The current star/galaxy separation algorithm is presented and the galaxy counts are nearly perfectly Euclidean. 95% complete and reliable galaxy…

Astrophysics · Physics 2007-05-23 Gary A. Mamon

The Gemini Deep Deep Survey (GDDS) is an ultra-deep (K<20.6 mag, I<24.5 mag) redshift survey targeting galaxies in the "redshift desert" between 1<z<2. The primary goal of the survey is to constrain the space density at high redshift of…

Selected results obtained in major observational sky surveys (DSS, 2MASS, 2dF, SDSS) and deep field observations (HDF, GOODS, HUDF, etc.) are reviewed. Modern surveys provide information on the characteristics and space distribution of…

Astrophysics · Physics 2009-11-11 V. P. Reshetnikov

Only galaxies bright enough and large enough to be unambiguously identified and measured are included in galaxy surveys used to estimate cosmic shear. We demonstrate that because gravitational lensing can scatter galaxies across the…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-17 Fabian Schmidt , Eduardo Rozo , Scott Dodelson , Lam Hui , Erin Sheldon

Like light, gravitational waves can be gravitationally lensed by massive astrophysical objects. Strong gravitational lensing by galaxies and galaxy clusters is anticipated to become observable in the coming years. This phenomenon will…

General Relativity and Quantum Cosmology · Physics 2025-06-03 Leo C. Y. Ng , Justin Janquart , Hemantakumar Phurailatpam , Harsh Narola , Jason S. C. Poon , Chris Van Den Broeck , Otto A. Hannuksela

The discovery of a gravitational lens candidate is reported. The quasars SDSS J111611.73+411821.5 and SDSS J111610.68+411814.4 are recognized as two images of the same object, being strongly lensed by the closer galaxy SDSS…

Astrophysics · Physics 2007-05-23 E. Sanchez Alvaro , F. J. Rodriguez Calonge

We present a spectroscopic survey of high-redshift, luminous galaxies over four square degrees on the sky, aiming to build a large and homogeneous sample of Ly$\alpha$ emitters (LAEs) at $z\approx5.7$ and 6.5, and Lyman-break galaxies…

We calculate the expected number of gravitationally lensed optical, radio and sub-mm lensed sources on the whole sky due to foreground galaxy clusters for different cosmological models. We improve previous calculations of lensed arc…

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

We present a framework for analyzing weak gravitational lensing survey data, including lensing and source-density observables, plus spectroscopic redshift calibration data. All two-point observables are predicted in terms of parameters of a…

Astrophysics · Physics 2014-11-18 Gary M. Bernstein