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Related papers: The Canada-France Redshift Survey X: The Quasar Sa…

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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 imaging and spectroscopic observations for six quasars at z>5.9 discovered by the Canada-France High-z Quasar Survey (CFHQS). The CFHQS contains sub-surveys with a range of flux and area combinations to sample a wide range of…

The Canada-France High-z Quasar Survey (CFHQS) is an optical survey designed to locate quasars during the epoch of reionization. In this paper we present the discovery of the first four CFHQS quasars at redshift greater than 6, including…

The photometric and spectroscopic data of the CFRS survey of objects with 17.5 < I_{AB} < 22.5 are combined and analysed. The overall completeness is 85%. The redshift histogram of the sample is presented for 591 field galaxies with secure…

Astrophysics · Physics 2016-08-30 David Crampton , O. Le Fevre , S. J. Lilly , F. Hammer

Possible surface brightness selection effects in the redshift catalogs of the Canada-France Redshift Survey are investigated through comparisons of subsamples of the data. Our analyses demonstrate that the securing of redshifts is…

Astrophysics · Physics 2009-10-28 F. Hammer , David Crampton , O. Le Fevre , S. J. Lilly

Being observed only one billion years after the Big Bang, z ~ 7 quasars are a unique opportunity for exploring the early Universe. However, only two z ~ 7 quasars have been discovered in near-infrared surveys: the quasars ULAS J1120+0641…

Astrophysics of Galaxies · Physics 2018-10-09 S. Pipien , J. G. Cuby , S. Basa , C. J. Willott , J. -C. Cuillandre , S. Arnouts , P. Hudelot

We report the discovery of five new doubly-imaged lensed quasars from the first 2500 square degrees of the ongoing Canada-France Imaging Survey (CFIS), which is a component of the Ultraviolet Near Infrared Optical Northern Survey (UNIONS),…

We report the discovery of five quasars with redshifts of 4.67 - 5.27 and z'-band magnitudes of 19.5-20.7 M_B ~ -27. All were originally selected as distant quasar candidates in optical/near-infrared photometry from the Sloan Digital Sky…

We report 250 GHz (1.2 mm) observations of a sample of 20 QSOs at redshifts 5.8<z<6.5 from the the Canada-France High-z Quasar Survey (CFHQS), using the Max-Planck Millimeter Bolometer (MAMBO) array at the IRAM 30-metre telescope. A rms…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 A. Omont , C. J. Willott , A. Beelen , J. Bergeron , G. Orellana , P. Delorme

We have observed a sample of 15 and 8 quasars with redshifts between 0.11 and 0.87 (mean value 0.38) in the J and K' bands respectively. Eleven of the quasars were previously known to be associated with extended emission line regions. After…

Astrophysics · Physics 2009-10-31 I. Marquez , F. Durret , P. Petitjean

The Canada-France Redshift Survey has been undertaken to provide a large well-defined sample of faint galaxies at high redshift in which the selection criteria match as closely as possible those of samples of nearby galaxies. The survey is…

Astrophysics · Physics 2009-10-28 S. J. Lilly , O. Le Fevre , David Crampton , F. Hammer , L. Tresse

This paper describes the methods used to obtain the spectroscopic data and construct redshift catalogs for the Canada-France deep Redshift Survey (CFRS). The full data set consists of more than one thousand spectra, of objects with 17.5 <…

Astrophysics · Physics 2016-08-30 O. Le Fevre , David Crampton , S. J. Lilly , F. Hammer , L. Tresse

Quasars are galaxies hosting accreting supermassive black holes; due to their brightness, they are unique probes of the early universe. To date, only few quasars have been reported at $z > 6.5$ ($<$800 Myr after the Big Bang). In this work,…

We report the discovery of 27 quasars with redshifts between 3.58 and 4.49. The objects were identified as high-redshift candidates based on their colors in Sloan Digital Sky Survey commissioning data. The redshifts were confirmed with low…

High-redshift quasars are currently the only probes of the growth of supermassive black holes and potential tracers of structure evolution at early cosmic time. Here we present our candidate selection criteria from the Panoramic Survey…

The X-ray luminosity function of distant (3<z<5.1) unabsorbed quasars has been measured. A sample of distant high-luminosity quasars ($10^{45} \leq L_{{\rm X},2-10} < 7.5 \times 10^{45}$ erg/s in the 2--10 keV energy band) from the catalog…

High Energy Astrophysical Phenomena · Physics 2019-06-21 G. A. Khorunzhev , S. Yu. Sazonov , R. A. Burenin

We present results on a search of heavily obscured active galaxies z>1.7 using the rest-frame 9-20 keV excess for X-ray sources detected in the deep XMM-CDFS survey. Out of 176 sources selected with the conservative detection criteria (>8…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 K. Iwasawa , R. Gilli , C. Vignali , A. Comastri , W. N. Brandt , P. Ranalli , F. Vito , N. Cappelluti , F. J. Carrera , S. Falocco , I. Georgantopoulos , V. Mainieri , M. Paolillo

We present follow-up spectroscopy to the Calar Alto Deep Imaging Survey (CADIS), reporting on the quasars in the CADIS 16h-field, and including preliminary data from two other fields. In this 10' x 10' field we found six quasars at redshift…

Astrophysics · Physics 2007-05-23 C. Wolf , K. Meisenheimer , H. -J. Roeser , CADIS team

We report the result of a faint quasar survey in a one square degree field. The aim is to test the Y-K/g-z and J-K/i-Y color selection criteria for quasars at faint magnitude, to obtain a complete sample of quasars based on deep optical and…

Astrophysics of Galaxies · Physics 2018-02-21 Jinyi Yang , Xue-Bing Wu , Dezi Liu , Xiaohui Fan , Qian Yang , Feige Wang , Ian D. McGreer , Zuhui Fan , Shuo Yuan , Huanyuan Shan

(Abridged) We analyse Hubble Space Telescope images of a complete sample of 341 galaxies drawn from both the Canada France and Autofib/Low Dispersion Survey Spectrograph ground-based redshift surveys. We discuss morphological…

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