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相关论文: The Hard X-Ray Luminosity Function of High-Redshif…

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Luminosity functions are one of the most important observational clues when studying galaxy evolution over cosmic time. In this paper we present the X-ray luminosity functions of X-ray detected AGN in the SXDS and GWS fields. The limiting…

This is the second paper of our investigation of the 0.5-2 keV soft X-ray luminosity function (SXLF) of active galactic nuclei (AGN) using results from ROSAT surveys of various depth. The large dynamic range of the combined sample, from…

天体物理学 · 物理学 2016-08-30 Takamitsu Miyaji , Guenther Hasinger , Maarten Schmidt

In the Hubble Deep Field (HDF), twelve candidate sources of high-redshift (z > 3.5) AGN activity have been identified. The color selection criteria were established by passing spectra of selected quasars and Seyfert galaxies (appropriately…

天体物理学 · 物理学 2009-10-31 R. Michael Jarvis , Gordon M. MacAlpine

We present an estimate of the space density of Active Galactic Nuclei (AGN) at z=3. Combining deep X-ray data with Lyman Break Galaxy (LBG) colour-selection in the rest-frame UV makes for highly efficient identification of AGN in a narrow…

天体物理学 · 物理学 2009-11-10 K. Nandra , E. S. Laird , C. C. Steidel

We used data from the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) to study the incidence of AGN in continuum-selected galaxies at $z\sim3$. From optical and infrared imaging in the 24 deg$^{2}$ Spitzer HETDEX Exploratory Large…

X-rays provide a robust method in identifying AGN. However, in the high-redshift Universe, their space density is relatively low, and, in combination with the small areas covered by X-ray surveys, the selected AGN are poorly sampled. Deep…

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

We present the latest determination of the X-ray (2-10 keV) AGN luminosity function accounting for the selection effect due to X-ray absorption. The main results are: 1) the inclusion of obscured AGN confirms the AGN differential luminosity…

天体物理学 · 物理学 2007-05-23 F. Fiore , the HELLAS2XMM collaboration

We study variability of active galactic nuclei (AGNs) by using the deep optical multiband photometry data obtained from the Hyper Suprime-Cam Subaru Strategic Program (HSC SSP) survey in the COSMOS field. The images analyzed here were taken…

星系天体物理 · 物理学 2020-05-13 Yuki Kimura , Toru Yamada , Mitsuru Kokubo , Naoki Yasuda , Tomoki Morokuma , Tohru Nagao , Yoshiki Matsuoka

In order to study the evolution of the relative fraction of obscured Active Galactic Nuclei (AGN) we constructed the largest sample to date of AGN selected in hard X-rays. The full sample contains 2341 X-ray-selected AGN, roughly 4 times…

天体物理学 · 物理学 2009-11-11 Ezequiel Treister , C. Megan Urry

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

Determinations of the UV luminosity function of AGN at high redshifts are important for constraining the AGN contribution to reionization and understanding the growth of supermassive black holes. Recent inferences of the luminosity function…

星系天体物理 · 物理学 2019-06-12 Girish Kulkarni , Gábor Worseck , Joseph F. Hennawi

For measurement of the AGN luminosity function and its evolution, X-ray selection samples all types of AGN and provides reduced obscuration bias in comparison with UV-excess or optical surveys. The apparent decline in optically-selected…

We model the evolution of active galactic nuclei by constructing their radio luminosity functions. We use a set of surveys of varying area and depth, namely the deep COSMOS survey of $1,916$ AGN sources, the wide shallow 3CRR, 7C and 6CE…

星系天体物理 · 物理学 2023-12-25 B. Šlaus , V. Smolcic , Ž. Ivezic , S. Fotopoulou , C. J. Willott , P. Pendo , C. Vignali , L. Chiappetti , M. Pierre

The luminosity function (LF) of active galactic nuclei (AGN) probes the history of supermassive black hole assembly and growth across cosmic time. To mitigate selection biases, we present a consistent analysis of the AGN LFs derived for…

[Abridged] To understand the role of the galaxy group environment on galaxy evolution, we present a study of radio luminosity functions (RLFs) of group galaxies based on the VLA-COSMOS 3 GHz Large Project. The radio-selected sample of 7826…

星系天体物理 · 物理学 2025-01-08 E. Vardoulaki , G. Gozaliasl , A. Finoguenov , M. Novak , H. G. Khosroshahi

We present the largest high-redshift (3<z<6.85) sample of X-ray-selected active galactic nuclei (AGN) on a contiguous field, using sources detected in the Chandra COSMOS Legacy survey. The sample contains 174 sources, 87 with spectroscopic…

We characterize the incidence of active galactic nuclei (AGNs) is 0.3 < z < 1 star-forming galaxies by applying multi-wavelength AGN diagnostics (X-ray, optical, mid-infrared, radio) to a sample of galaxies selected at 70-micron from the…

This study explores the space density and properties of active galaxies to z=0.8. We have investigated the frequency and nature of unresolved nuclei in galaxies at moderate redshift as indicators of nuclear activity such as Active Galactic…

天体物理学 · 物理学 2009-10-31 Vicki L. Sarajedini , Richard F. Green , Richard E. Griffiths , Kavan Ratnatunga

Given recent X-ray observations of high-redshift active galactic nuclei (AGNs), we consider whether the extreme luminosities of these AGNs are consistent with current semi-analytical models. In particular, we apply extreme-value statistics…

星系天体物理 · 物理学 2025-10-29 Cameron Heather , Teeraparb Chantavat , Siri Chongchitnan , Poemwai Chainakun