Group items tagged

The CLASS survey involved a hierarchical tree of ever-higher resolution radio imaging of flat spectrum radio sources with unusual morphologies. By focusing on the sources, not the lenses, the team was able to select the first well-defined, statistically complete sample of lensed objects. (A)

Gravitational lensing on the cluster scale is readily observed in almost all of the most massive systems, provided the image resolution and depth are high enough. "Blind" imaging surveys have also been carried out, most notably using SDSS data. Describes the candidate selection and confirmation of 16 new cluster-scale lenses. (A)

The SQLS project was similar to the CLASS survey in that a combination of spectra and imaging was used to make a statistical lens sample, but the data was all taken in the optical and near infrared. (A)

The most prolific lens search to date, the SLACS project involved high-resolution confirmation imaging of a very pure sample of lens candidates, selected for their anomalous SDSS double-galaxy spectra. (A)

This paper presents results from a combination of 4 blank-field surveys to achieve a 100 square degree total area, and contains a good discussion on how errors in Point Spread Function correction and background galaxy selection can propagate through to the cosmic-shear measurement. (A)

This paper describes an attempt to detect clusters by mass in a blank-field survey, thereby avoiding selection bias when measuring the evolution of the mass function. (A)

This paper presents results from a combination of 4 blank-field surveys to achieve a 100 square degree total area, and contains a good discussion on how errors in Point Spread Function correction and background galaxy selection can propagate through to the cosmic-shear measurement. (A)

This book was written to describe the science which is anticipated being performed using the Large Synoptic Survey Telescope, a future optical imaging facility. This provides an excellent starting point for exploring the current plans for making gravitational lensing measurements from future large area surveys, and what those measurements will enable. (A)

This paper discusses the impact on cosmological-parameter measurement from cosmic-shear surveys owing to catastrophic errors in photometric redshifts measurements. (A)

A recent and up-to-date paper on the distribution of stellar and dark matter in early-type galaxies using strong lensing, stellar kinematics, and other astrophysical tools. (A)

A recent description of the rationale for studying spiral galaxies with strong gravitational lensing and the challenges associated with finding large samples of them. (A)

In recent years, the citizen scientists of Galaxy Zoo have been carrying out their own search, rediscovering known lenses and finding interesting new candidates in the SDSS and HST image archives. They can be followed (and joined!) at the Galaxy Zoo forum. (E, I)

Weak lensing can be used to measure statistically the distribution of mass in structures that are not dense enough to be detected individually in mass reconstructions. This weak-lensing signal is conventionally known as "cosmic shear," and its measurement is one of the primary methods that has been proposed for accurately measuring cosmological parameters such as the matter and energy content of the universe, the curvature of the universe, and the scale of matter density fluctuations. From 2000-2002, several competing groups produced the first measurements of cosmic shear from surveys each covering ~10 square degrees. A summary of these results can be found in this review article.

Weak lensing can be used to measure statistically the distribution of mass in structures that are not dense enough to be detected individually in mass reconstructions. This weak-lensing signal is conventionally known as "cosmic shear," and its measurement is one of the primary methods that has been proposed for accurately measuring cosmological parameters such as the matter and energy content of the universe, the curvature of the universe, and the scale of matter density fluctuations. From 2000-2002, several competing groups produced the first measurements of cosmic shear from surveys each covering ~10 square degrees. A summary of these results can be found in this review article.

This paper presents results from the first analysis of a data set large enough to place significant constraints on the equation of state of dark energy. It includes a good discussion of how the constraints are measured and how systematic errors in the data can affect the results. (A)

This paper discusses the impact on cosmological-parameter measurement from cosmic-shear surveys owing to the intrinsic alignments of galaxy shapes (prior to their being lensed). (A)

This paper describes measurements of cosmic shear from a 2 square degree Hubble Space Telescope survey, combined with photometric redshifts of the lensed galaxies. The addition of the photometric redshifts allowed the authors to measure the evolution of the mass power-spectrum, which provides additional information about the cosmological model beyond what the integrated power-spectrum can provide.

This paper describes measurements of cosmic shear from a 2 square degree Hubble Space Telescope survey, combined with photometric redshifts of the lensed galaxies. The addition of photometric redshifts allowed the authors to produce a three dimensional reconstruction of the mass structures in the field. (A)

With the emphasis on generating mock data rather than modeling real data, this Javascript tool takes input lens, source and HST WFPC2 observation parameters and generates a predicted JPG image. (I,A)

A good summary of the methodology of weak lensing circa 2007, including much of the math often left out of other reviews (A).