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相关论文: The Luminosity Function Evolution of Soft X--ray s…

200 篇论文

We studied the Active Galactic Nuclei (AGN) radio emission from a compilation of hard X-ray selected samples, all observed in the 1.4 GHz band. A total of more than 1600 AGN with 2-10 keV de-absorbed luminosities higher than 10^42 erg/s…

宇宙学与河外天体物理 · 物理学 2015-05-19 F. La Franca , G. Melini , F. Fiore

The maximum number density of Active Galactic Nuclei (AGNs), as deduced from X-ray studies, occurs at z<~1, with lower luminosity objects peaking at smaller redshifts. Optical studies lead to a different evolutionary behaviour, with a…

天体物理学 · 物理学 2009-11-13 D. Trevese , F. Vagnetti , S. Puccetti , F. Fiore , M. Tomei , M. A. Bershady

We present a new determination of the optical luminosity function (OLF) of active galactic nuclei (AGN) at low redshifts (z<0.15) based on Hubble Space Telescope (HST) observations of X-ray-selected AGN. The HST observations have allowed us…

天体物理学 · 物理学 2015-06-24 D. Londish , B. J. Boyle , D. J. Schade

We use the INTEGRAL all-sky hard X-ray survey to perform a statistical study of a representative sample of nearby AGN. Our entire all-sky sample consists of 127 AGN, of which 91 are confidently detected (>5 sigma) on the time-averaged map…

天体物理学 · 物理学 2016-08-30 S. Sazonov , M. Revnivtsev , R. Krivonos , E. Churazov , R. Sunyaev

In this work, we aimed at investigating the star formation rate of active galactic nuclei host galaxies in the early Universe. To this end, we constructed a sample of 149 luminous ($\rm L_{2-10keV} > 10^{44}\,erg\,s^{-1}$) X-ray AGNs at…

We investigate how the fraction of broad-line sources in the AGN population changes with X-ray luminosity and redshift. We first construct the rest-frame hard-energy (2-8 keV) X-ray luminosity function (HXLF) at z=0.1-1 using Chandra…

天体物理学 · 物理学 2009-11-10 A. T. Steffen , A. J. Barger , L. L. Cowie , R. F. Mushotzky , Y. Yang

We perform a deep search for galaxies in the redshift range 6.5<z<7.5, to measure the evolution of the number density of luminous galaxies in this redshift range and derive useful constraints on the evolution of their Luminosity Function.…

We study the cosmic evolution of radio-loud active galactic nuclei (AGNs) using a beaming-minimized sample of 4{,}555 steep-spectrum sources over $0<z\lesssim4$, compiled from the XXL survey, VLA-COSMOS, and other wide-field data sets. We…

星系天体物理 · 物理学 2026-03-17 Wenjie Wang , Zunli Yuan , B. Šlaus , Hongwei Yu , Yu Luo

We present results from an analysis of the largest high-redshift (z > 3) X-ray-selected active galactic nucleus (AGN) sample to date, combining the Chandra C-COSMOS and ChaMP surveys and doubling the previous samples. The sample comprises…

星系天体物理 · 物理学 2015-06-22 E. Kalfountzou , F. Civano , M. Elvis , M. Trichas , P. Green

We present the first preliminary estimate of the evolution of type 1 AGNs at 15 um. A new sample of sources selected from the ELAIS-S1 survey has been used together with the RMS sample. The ELAIS-S1 survey covers an effective area of 2.2…

天体物理学 · 物理学 2007-05-23 F. La Franca , I. Matute , C. Gruppioni , D. Alexander , plus ELAIS consortium

We study the 850um emission in X-ray selected AGN in the 2 sq-deg COSMOS field using new data from the SCUBA-2 Cosmology Legacy Survey. We find 19 850um bright X-ray AGN in a high-sensitivity region covering 0.89 sq-deg with flux densities…

In the context of the upcoming SRG/eROSITA survey, we present an N-body simulation-based mock catalogue for X-ray selected AGN samples. The model reproduces the observed hard X-ray AGN luminosity function (XLF) and the soft X-ray logN-logS…

A new method is presented to obtain a non-parametric maximum likelihood estimate of the luminosity function and the selection function of a flux limited redshift survey. The method parameterizes the selection function as a series of…

天体物理学 · 物理学 2009-10-30 Volker Springel , Simon D. M. White

We present new methods to quantify the AGN population in terms of a multi-dimensional luminosity function that describes the space density of sources as a function of both X-ray and radio luminosity. We compile a sample of 1538 radio and…

高能天体物理现象 · 物理学 2025-11-19 Clara M. Pennock , James Aird , Cassandra L. Barlow-Hall

(Shortened Abstract) We present new X-ray data taken from the ROSAT PSPC pointing archive for 21 clusters in the Einstein Extended Medium Sensitivity Survey (EMSS). We have supplemented these data with new optical follow-up observations…

天体物理学 · 物理学 2009-10-28 R. C. Nichol , B. P. Holden , A. K. Romer , M. P. Ulmer , D. J. Burke , C. A. Collins

The cosmic evolution of the field galaxy population has been studied out to a redshift of z ~ 1 using a sample of 730 I-band selected galaxies, of which 591 have secure redshifts with median <z> ~ 0.56. The tri-variate luminosity function…

天体物理学 · 物理学 2009-10-28 S. J. Lilly , L. Tresse , F. Hammer , David Crampton , O. Le Fevre

A catalogue of 14453 radio-loud AGN with 1.4 GHz fluxes above 3.5 mJy in the redshift range 0.4<z<0.8, has been constructed from the cross-correlation of the NVSS and FIRST radio surveys with the MegaZ-LRG catalogue of luminous red galaxies…

天体物理学 · 物理学 2010-11-30 E. Donoso , P. N. Best , G. Kauffmann

We have measured the X-ray spectral properties of a complete flux-limited sample of bright AGNs from HEAO-1 all-sky catalogs to investigate their statistics and provide greater constraints on the bright-end of the hard X-ray luminosity…

天体物理学 · 物理学 2008-11-26 K. Shinozaki , T. Miyaji , Y. Ishisaki , Y. Ueda , Y. Ogasaka

The environmental properties of a sample of 31 hard X-ray selected AGN are investigated, from scales of 500 kpc down to 30 kpc, and are compared to a control sample of inactive galaxies. The AGN all lie in the redshift range 0.4<z<0.6. The…

天体物理学 · 物理学 2009-11-13 T. J. Waskett , S. A. Eales , W. K. Gear , H. J. McCracken , S. Lilly , M. Brodwin