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Related papers: Galaxies or Asteroids? -- 12 micron Sources in 9 Q…

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To build a large, optically bright, X-ray selected AGN sample we have correlated the ROSAT-FSC catalogue of X-ray sources with the USNO catalogue limited to objects brighter than O=16.5 and then with the APS database. Each of the 3,212…

In the paradigm of hierarchical galaxy formation, luminous radio galaxies mark mass assembly peaks that should contain clusters of galaxies. Observations of the z=1.53 quasar 3C270.1 with the Spitzer Space Telescope at 3.6-24 micron and…

We discuss broad- and narrow-band imaging of 7 arcmin fields of 14 QSOs with redshift ~1.1. The narrow-band filters were chosen to detect redshifted [O II] 3727A, and the broad bands are R and I, which correspond to rest wavelengths…

Astrophysics · Physics 2009-10-22 J. B. Hutchings , D. Crampton , Andrea Johnson

We have discovered a concentration of extremely red objects (EROs; R-K>6) in the field of the z=2.69 quasar QSO 1213-0017 (UM 485), which is significantly overabundant compared to the field ERO surface density. The optical/near-IR colors of…

As a pilot study for the first all-sky radio survey at short wavelengths, we have observed 1216 sq. deg. of the southern sky at 18GHz (16mm) using a novel wide-band (3.4GHz bandwidth) analogue correlator on one baseline of the Australia…

An "exotic" idea proposed by Viktor Ambartsumian was that new galaxies are formed through the ejection from older active galaxies. Galaxies beget galaxies, instead of the standard scenario in which galaxies stem from the evolution of the…

Cosmology and Nongalactic Astrophysics · Physics 2009-01-29 Martin Lopez-Corredoira

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…

The identification and study of the first galaxies remains one of the most exciting topics in observational cosmology. The determination of the best possible observing strategies is a very important choice in order to build up a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 A. Maizy , J. Richard , M. A. De Leo , R. Pello , J. P. Kneib

We present measurements of the clustering properties of galaxies in the field of redshift range $0.5 \lesssim z \lesssim 1.5$ Ultra Steep Spectrum (USS) radio sources selected from Sydney University Molonglo Sky Survey and NRAO VLA Sky…

Astrophysics · Physics 2009-11-11 Carlos G. Bornancini , Nelson Padilla , Diego G. Lambas , Carlos De Breuck

We propose that extrasolar asteroid belts can be detected through their gravitational microlensing signatures. Asteroid belt + star lens systems create so-called "pseudo-caustics", regions in the source plane where the magnification…

Earth and Planetary Astrophysics · Physics 2016-12-21 Ethan Lake , Zheng Zheng , Subo Dong

The genesis of spheroids is central to our understanding of galaxy formation -- they are relatively simple systems, containing about half the stellar mass of the Universe. A major subset of spheroids, massive elliptical galaxies, are…

Astrophysics · Physics 2009-11-10 J. A. Stevens , M. J. Page , R. J. Ivison , Ian Smail , F. J. Carrera

We present a new optical spectroscopic survey of 1777 'star-forming' ('SF') and 366 'non-star-forming' ('non-SF') galaxies at redshifts z < 1 (2143 in total), 22 AGN and 423 stars, observed by instruments such as DEIMOS, VIMOS and GMOS, in…

We analyse the large-scale structure out to 100 Mpc around a sample of 16 confirmed fossil systems using spectroscopic information from the Sloan Digital Sky Survey Data Release 16. We compute the distance between our FGs and the centres of…

Astrophysics of Galaxies · Physics 2022-12-07 S. Zarattini , J. A. L. Aguerri , R. Calvi , M. Girardi

We present a quantitative analysis of the astrophysical and cosmological information that can be extracted from the many important wide-area, shallow surveys that will be carried out in the next few years. Our calculations combine the…

There is controversy about the measurement of statistical associations between bright quasars and faint, presumably foreground galaxies. We look at the distribution of galaxies around an unbiased sample of 63 bright, moderate redshift…

Astrophysics · Physics 2015-06-24 P. A. Thomas , R. L. Webster , M. J. Drinkwater

Measurements of QSO clustering in the SDSS show that $\mathrm{z}>4$ QSOs are some of the most highly biased objects in the universe. Their large correlation lengths of $r_0 \sim 20h^{-1}$Mpc are comparable to the most massive clusters of…

Astrophysics of Galaxies · Physics 2015-06-22 Scott M. Adams , Paul Martini , Kevin V. Croxall , Roderik A. Overzier , John D. Silverman

We present the first results of a survey designed to understand the origin of the Lyman alpha-forest absorption systems at low redshift. Using the WYFFOS and HYDRA multi-fibre spectrographs on the WHT and WIYN telescopes, we have identified…

Astrophysics · Physics 2009-10-30 David V. Bowen , Max Pettini , Brian Boyle

A primary goal of the SCUBA-2 Web survey is to perform tomography of the early inter-galactic medium by studying systems containing some of the brightest quasi-stellar objects (QSOs; 2.5<z<3.0) and nearby submillimetre galaxies. As a first…

Eighteen candidates for emission line galaxies were discovered in a narrow-band infrared survey that targeted the redshifts of damped Lyman-alpha or metal lines in the spectra of quasars. The presence of emission lines is inferred from the…

Astrophysics · Physics 2009-10-30 F. Mannucci , D. Thompson , S. V. W. Beckwith , G. M. Williger

We present a catalog of 30 QSOs and their spectra, in the square degree of sky centered on the northern Hubble Deep Field. These QSOs were selected by multicolor photometry and subsequently confirmed with spectroscopy. They range in…

Astrophysics · Physics 2014-10-13 Charles Liu , Cathy Petry , Chris Impey , Craig Foltz