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Related papers: Constraining the Redshift z=6 Quasar Luminosity Fu…

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We present discovery imaging and spectroscopy for nine new z ~ 6 quasars found in the Canada-France High-z Quasar Survey (CFHQS) bringing the total number of CFHQS quasars to 19. By combining the CFHQS with the more luminous SDSS sample we…

We present simulations of quasar colors, magnitudes, and numbers at redshifts 5<z<10 based on our discovery of ten new high-redshift quasars and the cloning of lower redshift Sloan Digital Sky Survey (SDSS) quasars. The ten quasars have…

We present an analysis of seven strongly gravitationally lensed quasars and the corresponding constraints on the properties of dark matter. Our results are derived by modelling the lensed image positions and flux-ratios using a combination…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Jen-Wei Hsueh , Wolfgang Enzi , Simona Vegetti , Matt Auger , Christopher D. Fassnacht , Giulia Despali , Leon V. E. Koopmans , John P. McKean

Direct observations of the first generation of luminous objects will likely become feasible over the next decade. The advent of the Next Generation Space Telescope (NGST) will allow imaging of numerous galaxies and mini-quasars at redshifts…

Astrophysics · Physics 2009-10-31 Rennan Barkana , Abraham Loeb

When gravitational waves pass near massive astrophysical objects, they can be gravitationally lensed. The lensing can split them into multiple wave-fronts, magnify them, or imprint beating patterns on the waves. Here we focus on the…

High Energy Astrophysical Phenomena · Physics 2021-11-17 A. Renske A. C. Wierda , Ewoud Wempe , Otto A. Hannuksela , Léon V. E. Koopmans , Chris Van Den Broeck

We report the discovery, spectroscopic confirmation, and mass modelling of the gravitationally lensed quasar system PS J0630-1201. The lens was discovered by matching a photometric quasar catalogue compiled from Pan-STARRS and WISE…

Gravitational lensing deflects light. A single lens deflector can only shear images, but cannot induce rotations. Multiple lens planes can induce rotations. Such rotations can be observed in quadruply imaged sources, and can be used to…

Astrophysics · Physics 2010-11-19 Ue-Li Pen , Shude Mao

We use a series of ray-tracing experiments to determine the magnification distribution of high-redshift sources by gravitational lensing. We determine empirically the relation between magnification and redshift, for various cosmological…

Astrophysics · Physics 2007-05-23 Premana Premadi , Hugo Martel

Large-scale surveys over the last years have revealed about 300 QSOs at redshift above 6. Follow-up observations identified surprising properties, such as the very high black hole (BH) masses, spatial correlations with surrounding cold gas…

Astrophysics of Galaxies · Physics 2021-10-20 J. Greiner , J. Bolmer , R. M. Yates , M. Habouzit , E. Banados , P. M. J. Afonso , P. Schady

The gravitational lensing, as well as the velocity field and the cosmological light-cone warp, changes the observed correlation function of high-redshift objects. We present an analytical expression of 3D correlation function,…

Astrophysics · Physics 2009-10-31 Takahiko Matsubara

In this paper, we present a derivation of the rest-frame 1400A luminosity function (LF) at redshift six from a new application of the maximum likelihood method by exploring the five deepest HST/ACS fields, i.e., the HUDF, two UDF05 fields,…

We present the discovery of nine quasars at $z\sim6$ identified in the Sloan Digital Sky Survey (SDSS) imaging data. This completes our survey of $z\sim6$ quasars in the SDSS footprint. Our final sample consists of 52 quasars at…

Gravitational lensing of gravitational waves (GWs) is a powerful probe of the matter distribution in the universe. Here we revisit the wave-optics effects induced by dark matter (DM) halos on the GW signals of merging massive black hole…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-23 Zucheng Gao , Xian Chen , Yi-Ming Hu , Jian-Dong Zhang , Shunjia Huang

We combine a large set of quasar luminosity function (QLF) measurements from the rest-frame optical, soft and hard X-ray, and near- and mid-infrared bands to determine the bolometric QLF in the redshift interval z=0-6. Accounting for the…

Astrophysics · Physics 2008-11-26 Philip F. Hopkins , Gordon T. Richards , Lars Hernquist

The dark halo substructures predicted by current cold dark matter simulations may in principle be detectable through strong-lensing image splitting of quasars on small angular scales (0.01 arcseconds or below). Here, we estimate the overall…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-22 T. Riehm , E. Zackrisson , E. Mortsell , K. Wiik

We report the discoveries of two, two-image gravitationally lensed quasars selected from the Sloan Digital Sky Survey: SDSS J0806+2006 at z_s=1.540 and SDSS J1353+1138 at z_s=1.629 with image separations of 1.40" and 1.41" respectively.…

Bright gravitationally lensed galaxies provide our most detailed view of galaxies at high redshift. Yet as a result of the small number of ultra-bright z~2 lensed systems with confirmed redshifts, most detailed spectroscopic studies have…

With the increase in the number of observed gravitational wave (GW) signals, detecting strongly lensed GWs by galaxies has become a real possibility. Lens galaxies also contain microlenses (e.g., stars and black holes), introducing further…

Astrophysics of Galaxies · Physics 2022-10-05 Ashish Kumar Meena , Anuj Mishra , Anupreeta More , Sukanta Bose , Jasjeet Singh Bagla

We try to explain quasar-galaxy associations by gravitational lensing by globular clusters, located in the halos of foreground galaxies. We propose observational test for verification of this hypothesis. We processed SUPERCOSMOS sky survey…

Astrophysics · Physics 2007-05-23 A. Yushchenko , Chulhee Kim , A. Sergeev , P. Niarchos , V. Manimanis

We present 6-GHz Very Large Array radio images of 70 gravitational lens systems at 300-mas resolution, in which the source is an optically-selected quasar, and nearly all of which have two lensed images. We find that about in half of the…

Astrophysics of Galaxies · Physics 2024-04-05 Neal Jackson , Shruti Badole , Thomas Dugdale , Hannah R. Stacey , Philippa Hartley , J. P. McKean , .