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Related papers: High-redshift quasars lensed by spiral galaxies

200 papers

We present VLT/X-shooter spectra of 13 galaxies in the redshift range 1< z < 6, which are strongly lensed by massive galaxy clusters. Spectroscopic redshifts are measured for nine galaxies, while three sources have redshifts determined from…

A number of deep, wide-field, near-infrared surveys employing new infrared cameras on 4m-class telescopes are about to commence. These surveys have the potential to determine the fraction of luminous dust-obscured quasars that may have…

Astrophysics · Physics 2009-11-11 Natasha Maddox , Paul C. Hewett

Recent observations by the James Webb Space Telescope have revealed massive galaxies at very high redshift ($z\simeq 7-15$). The question of whether the existence of such galaxies is expected in the corresponding JWST surveys has received a…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-18 Qianran Xia , Dragan Huterer , Nhat-Minh Nguyen

Three high-redshift (z=2) and high luminosity (M_B < -28 mag for Ho = 50, qo=0.5) QSOs, two radio-quiet one radio-loud, were imaged in R, I and K bands. The luminosities, colours and sizes of the hosts overlap with those of actively…

Astrophysics · Physics 2007-05-23 I. Aretxaga , R. J. Terlevich , B. J. Boyle

Several high-z (z > 5.7) quasars have been found in the course of Sloan Digital Sky Survey. The presence of such very high-z quasars is expected to give constraints on early structure formation. On one hand, it is suggested that these most…

Strong lensing in galaxy clusters probes properties of dense cores of dark matter halos in mass, studies the distant universe at flux levels and spatial resolutions otherwise unavailable, and constrains cosmological models independently.…

Instrumentation and Methods for Astrophysics · Physics 2023-01-04 Peng Jia , Ruiqi Sun , Nan Li , Yu Song , Runyu Ning , Hongyan Wei , Rui Luo

Redshift distortions, both geometrical and kinematical, of quasar clustering are simulated, for the Two-Degree Field QSO Redshift Survey (2QZ), showing that they are very effective to constrain the cosmological density and equation of state…

Astrophysics · Physics 2007-05-23 M. O. Calvao , J. R. T. de Mello Neto , I. Waga

Obscuration in quasars may arise from steep viewing angles along the dusty torus, or instead may represent a distinct phase of supermassive black hole growth. We test these scenarios by probing the host dark matter halo environments of…

We calculate the observable properties of the most massive high-redshift galaxies in the hierarchical formation scenario where stellar spheroid and supermassive black hole growth are fueled by gas-rich mergers. Combining high-resolution…

Astrophysics · Physics 2010-11-05 Brant Robertson , Yuexing Li , Thomas J. Cox , Lars Hernquist , Philip F. Hopkins

WL measurements have well-known shear estimation biases, which can be partially corrected for with the use of image simulations. We present an analysis of simulated images that mimic HST/ACS observations of high-redshift galaxy clusters,…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-26 B. Hernandez-Martin , T. Schrabback , H. Hoekstra , N. Martinet , J. Hlavacek-Larrondo , L. E. Bleem , M. D. Gladders , B. Stalder , A. A. Stark , M. Bayliss

For 18 well-observed gravitationally lensed QSOs, we compare new non-parametric mass profiles for the lensing galaxies with stellar-population models derived from published HST photometry. The large volume of parameter space searched --…

Astrophysics · Physics 2009-11-10 Ignacio Ferreras , Prasenjit Saha , Liliya L. R. Williams

We have analysed the optical luminosity-redshift distribution properties of bright QSOs, using a new large sample from the Hamburg/ESO survey. The sample provides insight into the hitherto poorly sampled bright tail of the luminosity…

Astrophysics · Physics 2007-05-23 Lutz Wisotzki

We discuss the utility of a low resolution prism as a component of a Multi-Object Spectrometer for NASA's proposed Next Generation Space Telescope (NGST). Low resolution prism spectroscopy permits simultaneous observation of the 0.6-5micron…

Strong gravitational lensing enables a wide range of science: probing cosmography; testing dark matter models; understanding galaxy evolution; and magnifying the faint, small and distant Universe. However to date exploiting strong lensing…

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

This paper presents the first results of a survey for bright quasars (V < 14.5 and R<15.4) covering the North Hemisphere at galactic latitudes |b|>30. The photometric database is derived from the GSC and USNO catalogs. Quasars are…

Astrophysics · Physics 2009-10-31 A. Grazian , S. Cristiani , V. D'Odorico , A. Omizzolo , A. Pizzella

Absorption-line spectroscopy of multiply-lensed QSOs near a known foreground galaxy provides a unique opportunity to go beyond the traditional one-dimensional application of QSO probes and establish a crude three-dimensional (3D) map of…

Astrophysics of Galaxies · Physics 2019-08-19 Hsiao-Wen Chen , Jean-Rene Gauthier , Keren Sharon , Sean D. Johnson , Preethi Nair , Cameron J. Liang

Damped Lyman-alpha absorbers are believed to be associated with galactic disks. We show that gravitational lensing can therefore affect the statistics of these systems. First, the magnification bias due to lensing raises faint QSOs above a…

Astrophysics · Physics 2009-10-28 Matthias Bartelmann , Abraham Loeb

Although about a dozen high redshift (z larger than 2) starburst galaxies have been recently detected in the CO lines, spectroscopic detections of molecular gas of very young galaxies are still very difficult. The CO lines are usually…

Astrophysics · Physics 2017-08-23 F. Combes