Related papers: Quasar Luminosity Function at z = 7

We publicly release a new sample of $34$ medium resolution quasar spectra at $5.77\leq z_{\rm em}\leq6.54$ observed with the Echellette Spectrograph and Imager (ESI) on the Keck telescope. This quasar sample represents an ideal laboratory…

We expect luminous ($M_{1450}\lesssim-26.5$) high-redshift quasars to trace the highest density peaks in the early universe. Here, we present observations of four $z\gtrsim6$ quasar fields using JWST/NIRCam in imaging and widefield slitless…

We determine the luminosity function (LF) of galaxies in the core of the Coma cluster for M_R<=-11.4 (assuming H_0=75 km/s/Mpc), a magnitude regime previously explored only in the Local Group. Objects are counted in a deep CCD image of Coma…

We present the largest-ever sample of 79 Ly$\alpha$ emitters (LAEs) at $z\sim$ 7.0 selected in the COSMOS and CDFS fields of the LAGER project (the Lyman Alpha Galaxies in the Epoch of Reionization). Our newly amassed ultradeep narrowband…

We predict the effects of gravitational lensing on the color-selected flux-limited samples of z~4.3 and z>5.8 quasars, recently published by the Sloan Digital Sky Survey (SDSS). Our main findings are: (i) The lensing probability should be…

We carried out extended spectroscopic confirmations of Ly-alpha emitters (LAEs) at z=6.5 and 5.7 in the Subaru Deep Field. Now, the total number of spectroscopically confirmed LAEs is 45 and 54 at z=6.5 and 5.7, respectively, and at least…

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 present the cross-correlation between 151 luminous quasars ($M_{ \mathrm{UV}} < -26$) and 179 protocluster candidates at $z \sim 3.8$, extracted from the Wide imaging survey ($ \sim 121~ $deg$^2$) performed with a part of the Hyper…

Fermi has provided the largest sample of {\gamma}-ray selected blazars to date. In this work we use a complete sample of FSRQs detected during the first year of operation to determine the luminosity function (LF) and its evolution with…

The observed large-scale scatter in Lyman $\alpha$ opacity of the intergalactic medium at $z<6$ implies large fluctuations in the neutral hydrogen fraction that are unexpected long after reionization has ended. A number of models have…

Using wide field narrow-band surveys, we provide a new measurement of the $z=6.6$ Lyman-$\alpha$ Emitter (LAE) luminosity function (LF), which constraints the bright end for the first time. We use a combination of archival narrow-band NB921…

We present the results of the Quasars near Quasars (QNQ) survey, a CCD-based slitless spectroscopic survey for faint V<22 quasars at 1.7<z<3.6 on 18 26.2'x33.5' fields centred on bright quasars at 2.76<z<4.69. In total 169 quasar candidates…

We conducted a deep narrowband NB973 (FWHM = 200 A centered at 9755 A) survey of z=7 Lyman alpha emitters (LAEs) in the Subaru/XMM-Newton Deep Survey Field, using the fully depleted CCDs newly installed on the Subaru Telescope Suprime-Cam,…

We present deep Chandra observations of PSO J231.6576$-$20.8335, a quasar at redshift z=6.59 with a nearby (${\sim}8$ proper kpc) companion galaxy. ALMA observed both the quasar and companion to be bright in [C II], and the system has…

The discovery of the first strongly lensed $(\mu \approx 50)$ quasar at $z>6$ (J0439+1634) represents a breakthrough in our understanding of the early Universe. We derive the theoretical consequences of the new discovery. We predict that…

Observations with the Wide-Field Camera of the Hubble Space Telescope are presented for a representative sample of 20 intrinsically luminous quasars with redshifts smaller than 0.30. These observations show that luminous quasars occur in…

The intergalactic medium was not completely reionized until approximately a billion years after the Big Bang, as revealed by observations of quasars with redshifts of less than 6.5. It has been difficult to probe to higher redshifts,…

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 first discovery of dust-reddened quasars (red quasars) in the high-z universe (z >5.6). This is a result from the Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs) project, which is based on the sensitive…

We present a study of the galaxy Lyman-alpha luminosity function (LF) using a sample of 17 lensing clusters observed by the MUSE/VLT. Magnification from strong gravitational lensing by clusters of galaxies and MUSE apabilities allow us to…