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Related papers: A Cluster of High Redshift Quasars with Apparent D…

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We report the discovery of two quasars at a redshift of $z$ = 6.05, in the process of merging. They were serendipitously discovered from the deep multi-band imaging data collected by the Hyper Suprime-Cam (HSC) Subaru Strategic Program…

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…

We present our first results of the survey for high redshift quasars at $5 \lesssim {\rm z} \lesssim 5.7$. The search for quasars in this redshift range has been known to be challenging due to limitations of filter sets used in previous…

We present 547 optical redshifts obtained for galaxies in the region of the Horologium-Reticulum Supercluster (HRS) using the 6dF multi-fiber spectrograph on the UK Schmidt Telescope at the Anglo Australian Observatory. The HRS covers an…

We study the infrared (K_s band) properties of clusters of galaxies in the Ursa Major supercluster using data from 2MASS (Two-Micron All-Sky Survey) and SDSS (Sloan Digital Sky Survey). We identified three large filaments with mean…

Astrophysics · Physics 2009-11-11 Flera Kopylova , Alexander Kopylov

We present Chandra X-ray observations of 14 radio-loud quasars at redshifts $3 < z < 4$, selected from a well-defined sample. All quasars are detected in the 0.5-7.0 keV energy band, and resolved X-ray features are detected in five of the…

We carried out a Subaru and UKIRT near infrared imaging survey for H-alpha emitting galaxies around two pair quasar systems (Q0301-005/Q0302-003 and Q2343+125/Q2344+125), and a triple quasar system (KP76/KP77/KP78). Narrow band near…

Astrophysics · Physics 2008-11-26 Toru Misawa , Nobunari Kashikawa , Youichi Ohyama , Tetsuya Hashimoto , Masanori Iye

We study the dependence of the number density and properties of quasars on the background galaxy density using the currently largest spectroscopic datasets of quasars and galaxies. We construct a galaxy number density field smoothed over…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-17 Hyunmi Song , Changbom Park , Heidi Lietzen , Maret Einasto

We report a promising candidate for a distant supercluster at z $\sim 1.1$ in the Dark Energy Survey Science Verification data. We examine smoothed semi-3D galaxy density maps in various photo-z slices. Among several overdense regions, in…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-11 Tapish Narwal , Tomotsugu Goto , Tetsuya Hashimoto , Seong Jin Kim , Chia-Ying Chiang , Yi-Han Wu

We present submillimetre continuum observations of a sample of some of the highest redshift quasars currently known, made with the SCUBA bolometer array on the JCMT. The median redshift of the sample is 5.3. Two z>5 objects are strong (6…

Astrophysics · Physics 2009-11-10 Robert S. Priddey , Kate G. Isaak , Richard G. McMahon , E. I. Robson , C. P. Pearson

We present a near-infrared quasar composite spectrum spanning the wavelength range 0.58 - 3.5 um. The spectrum has been constructed from observations of 27 quasars obtained at the NASA IRTF telescope and satisfying the criteria Ks < 14.5…

Astrophysics · Physics 2009-11-13 Eilat Glikman , David J. Helfand , Richard L. White

In preceding papers of this series, TF relations for galaxies in 24 clusters with radial velocities between 1000 and 9200 km/s (SCI sample) were obtained, a Tully-Fisher (TF) template relation was constructed and mean offsets of each…

Astrophysics · Physics 2009-10-30 R. Giovanelli , M. Haynes , J. Salzer , G. Wegner , L. da Costa , W. Freudling

The Cl 1604 supercluster at z~0.9 is known to contain at least four distinct member clusters, separated in both projection and redshift. In this paper we present deep, multicolor wide-field imaging of a region spanning ~45' on a side,…

Astrophysics · Physics 2009-11-10 R. R. Gal , L. M. Lubin , G. K. Squires

We present constraints on the evolution of large-scale structure from a catalog of 710,000 galaxies with I_AB <= 24 derived from a KPNO 4m CCD imaging survey of a contiguous 4 deg x 4 deg region. The advantage of using large contiguous…

Astrophysics · Physics 2009-10-30 Marc Postman , Tod R. Lauer , Istvan Szapudi , William Oegerle

UGC 8584 was selected by a computer program as having a number of quasars around it that obeyed the Karlsson periodicity in its reference frame. On closer examination 9 of the nearest 10 quasars turned out to be extremely close to the…

Astrophysics · Physics 2008-03-19 H. Arp , C. Fulton

We have observed a sample of 22 luminous quasars, in the range 2.0<z<2.5, at 1.6 microns with the near-infrared (NIR) spectrograph FSPEC on the Multiple Mirror Telescope. Our sample contains 13 radio-loud and 9 radio-quiet objects. We have…

Astrophysics · Physics 2009-10-31 D. H. McIntosh , H. -W. Rix , M. J. Rieke , C. B. Foltz

We present near-IR, low resolution spectra of eight of the most distant quasars known, with redshifts in the range 4.9<z<6.4. Half of these quasars are characterized by deep, broad and blueshifted absorption features associated with both…

Astrophysics · Physics 2009-11-10 R. Maiolino , E. Oliva , F. Ghinassi , M. Pedani , F. Mannucci , R. Mujica , Y. Juarez

We present the results of carrying out multi-object spectroscopy in 10 EIS cluster fields. Based on the list of 345 galaxy redshifts we identify significant 3D-density enhancements. For 9 of the EIS clusters we identify significant…

Astrophysics · Physics 2009-11-10 L. F. Olsen , L. Hansen , H. E. Joergensen , C. Benoist , L. da Costa , M. Scodeggio

We present Hubble Space Telescope imaging of two ultra diffuse galaxies (UDGs) with measured stellar velocity dispersions in the Coma cluster. The galaxies, Dragonfly 44 and DFX1, have effective radii of 4.7 kpc and 3.5 kpc and velocity…

We report the first results of an observational program designed to determine the luminosity density of high redshift quasars (z > 5 quasars) using deep multi-colour CCD data. We report the discovery and spectra of 3 i < 21.5 high redshift…

Astrophysics · Physics 2018-05-09 R. G. Sharp , R. G. McMahon , M. J. Irwin , S. T. Hodgkin