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Related papers: Quasar Luminosity Function at z = 7

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We present ALMA [CII] line and far-infrared (FIR) continuum observations of three $z > 6$ low-luminosity quasars ($M_{\rm 1450} > -25$) discovered by our Subaru Hyper Suprime-Cam (HSC) survey. The [CII] line was detected in all three…

We detect 20 $z=7.0$ Ly$\alpha$ emitter (LAE) candidates to $L({\rm Ly}\alpha) \geq 2 \times 10^{42}$ erg s$^{-1}$ or $0.3$ $L^*_{z=7}$ and in $6.1\times 10^5$ Mpc$^3$ volume in the Subaru Deep Field and the Subaru/XMM-Newton Deep Survey…

We present the discovery of three new quasars at z>6 in 1300 deg^2 of SDSS imaging data, J114816.64+525150.3 (z=6.43), J104845.05+463718.3 (z=6.23) and J163033.90+401209.6 (z=6.05). The first two objects have weak Ly alpha emission lines;…

The observed lensed fraction of high-redshift quasars $(\sim0.2\%)$ is significantly lower than previous theoretical predictions $(\gtrsim4\%)$. We revisit the lensed fraction of high-redshift quasars predicted by theoretical models, where…

Astrophysics of Galaxies · Physics 2022-02-09 Minghao Yue , Xiaohui Fan , Jinyi Yang , Feige Wang

Infrared luminosities vLv(7.8 um) arising from dust reradiation are determined for Sloan Digital Sky Survey (SDSS) quasars with 1.4 < z < 5 using detections at 22 um by the Wide-Field Infrared Survey Explorer. Infrared luminosity does not…

Astrophysics of Galaxies · Physics 2016-08-31 Valeri Vardanyan , Daniel Weedman , Lusine Sargsyan

This is the fourth paper in a series aimed at finding high-redshift quasars from five-color imaging data taken along the Celestial Equator by the SDSS. during its commissioning phase. In this paper, we use the color-selected sample of 39…

Recent observations of z >~ 7 Ly{\alpha} emitters (LAEs) have derived a variety of Ly{\alpha} luminosity functions (LFs) with contradictory results, evolution or non-evolution from z <~ 6, the epoch after reionization. This could be because…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Kazuaki Ota , Masanori Iye

We carry out a series of deep Karl G. Jansky Very Large Array (VLA) S-band observations of a sample of 21 quasars at $z\sim6$. The new observations expand the searches of radio continuum emission to the optically faint quasar population at…

Using recent empirical constraints on the dark matter halo--galaxy--supermassive black hole (SMBH) connection from $z=0-7$, we infer how undermassive, typical, and overmassive SMBHs contribute to the quasar luminosity function (QLF) at…

Astrophysics of Galaxies · Physics 2023-05-31 Haowen Zhang , Peter Behroozi , Marta Volonteri , Joseph Silk , Xiaohui Fan , Philip F. Hopkins , Jinyi Yang , James Aird

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

The recently-finished Edinburgh UVX quasar survey at B < 18 is used together with other complete samples to estimate the shape and evolution of the optical luminosity function in the redshift range 0.3 < z < 2.2. There is a significantly…

Astrophysics · Physics 2009-07-28 Pippa Goldschmidt , Lance Miller

We present spectroscopic Ly$\alpha$ luminosity functions (LFs) at z = 5.7 and z = 6.6 based on a large 209 source sample of Ly$\alpha$ emitter (LAE) candidates identified in Subaru/Hyper Suprime-Cam narrowband imaging and confirmed with…

Astrophysics of Galaxies · Physics 2025-06-18 A. J. Taylor , A. J. Barger , L. L. Cowie , E. M. Hu , A. Songaila

We present new Chandra observations of seven luminous quasars at $z>6.5$. Combined with archival Chandra observations of all other known quasars, they form nearly complete X-ray observations of all currently known $z\sim7$ quasars with…

We present the results from a MUSE survey of twelve $z\simeq3.15$ quasars, which were selected to be much fainter (20<i<23) than in previous studies of Giant Ly$\alpha$ Nebulae around the brightest quasars (16.6<i<18.7). We detect HI…

We investigate the predictions for the faint-end quasar luminosity function (QLF) and its evolution using fully cosmological hydrodynamic simulations which self-consistently follow star formation, black hole growth and associated feedback…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Colin DeGraf , Tiziana Di Matteo , Volker Springel

We present the discovery of six new quasars at z~6 selected from the Sloan Digital Sky Survey (SDSS) southern survey, a deep imaging survey obtained by repeatedly scanning a stripe along the celestial equator. The six quasars are about two…

We present the results from a survey of i-dropout objects selected from ~1550 deg^2 of multicolor imaging data from the Sloan Digital Sky Survey, to search for luminous quasars at z>5.8. Objects with i*-z*>2.2 and z*<20.2 are selected, and…