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Related papers: Quasars and the Big Blue Bump

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We present the review of some new problems in cosmology and physics of stars in connection with future launching of WSO. We discuss three problems. UV observations of distant z > 6 quasars allow to obtain information on the soft < 1 KeV…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Yu. N. Gnedin , M. Yu. Piotrovich , T. M. Natsvlishvili

We present the rest-frame near-ultraviolet (NUV) spectroscopy of star-forming galaxies (SFGs) at 0.6<z<1.2 from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS) in SDSS-IV. One of the eBOSS programs is to obtain 2 arcsec (about…

We present a sample of 252 broad-line Active Galactic Nuclei (BLAGNs), incorporating 171 newly identified sources, spanning a redshift interval from $z$ = 0.8 to 7.2. We have analyzed spectroscopic data from the NIRSpec instrument aboard…

Astrophysics of Galaxies · Physics 2025-12-04 Caroline Baccus , Xinfeng Xu

We present near-infrared K- (1.9-2.5 micrometer) and L- (2.8-4.2 micrometer) band spectroscopy of 22 Seyfert nuclei. We use two methods to investigate the presence of nuclear starbursts: (1) the Polycyclic Aromatic Hydrocarbon (PAH)…

Astrophysics of Galaxies · Physics 2015-05-20 Nagisa Oi , Masatoshi Imanishi , Keisuke Imase

This paper presents a survey of X-ray selected active galactic nuclei (AGN) with optical spectroscopic follow-up in a $\sim 18\, \rm{deg^2}$ area of the equatorial XMM-XXL north field. A sample of 8445 point-like X-ray sources detected by…

We carried out a systematic analysis of time lags between X-ray energy bands in a large sample (32 sources) of unabsorbed, radio quiet active galactic nuclei (AGN), observed by XMM-Newton. The analysis of X-ray lags (up to the…

High Energy Astrophysical Phenomena · Physics 2015-06-03 B. De Marco , G. Ponti , M. Cappi , M. Dadina , P. Uttley , E. M. Cackett , A. C. Fabian , G. Miniutti

It is established that the ultraviolet (UV) and X-ray emissions in active galactic nuclei (AGN) are tightly correlated. This correlation is observed both in low- and high-redshift sources. In particular, observations of large samples of…

High Energy Astrophysical Phenomena · Physics 2025-03-27 E. Kammoun , I. E. Papadakis , M. Dovčiak , E. Lusso , E. Nardini , G. Risaliti

Radiation from the blazar class of of active galactic nuclei (AGN) exhibits fast time variability which is usually ascribed to instabilities in the emission region near the central supermassive black hole. The variability time scale is…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Kenji Nakagawa , Masaki Mori

We performed near-diffraction-limited (~0.4 FWHM) N-band imaging of one of the nearest Active Galactic Nucleus (AGN) in M51 with 8.2m Subaru telescope to study the nuclear structure and spectral energy distribution (SED) at 8-13 um. We…

Astrophysics of Galaxies · Physics 2017-02-01 Youichi Ohyama , Satoki Matsushita , Nagisa Oi , Ai-Lei Sun

Pulsar wind nebulae (PWNe) are one of the most energetic galactic sources with bright emissions from radio waves to very high-energy gamma-rays. We perform wideband X-ray spectroscopy of four energetic PWNe, N157B, PSR J1813-1749, PSR…

High Energy Astrophysical Phenomena · Physics 2022-08-24 Aya Bamba , Shinpei Shibata , Shuta J. Tanaka , Koji Mori , Hiroyuki Uchida , Yukikatsu Terada , Wataru Ishizaki

$\require{mediawiki-texvc}$ Supermassive black holes at the centre of active galactic nuclei (AGN) produce relativistic jets that can affect the star formation characteristics of the AGN hosts. Observations in the ultraviolet (UV) band can…

Astrophysics of Galaxies · Physics 2022-09-14 Prajwel Joseph , P. Sreekumar , C. S. Stalin , K. T. Paul , Chayan Mondal , Koshy George , Blesson Mathew

We present a UV spectroscopic study of ionized outflows in 21 active galactic nuclei (AGN), observed with the HST. The targets of the SUBWAYS sample were selected with the aim to probe the parameter space of the underexplored AGN between…

The well-known anti-correlation between the optical/ultraviolet (UV) emission line equivalent widths of active galactic nuclei and the continuum luminosity (the so-called Baldwin effect) is a long-standing puzzle. One common hypothesis is…

Astrophysics of Galaxies · Physics 2023-10-09 Zhen-Yi Cai , Jun-Xian Wang

We aim to study the effect of environment on the presence and fuelling of Active Galactic Nuclei (AGN) in massive galaxy clusters. We explore the use of different AGN detection techniques with the goal of selecting AGN across a broad range…

Astrophysics of Galaxies · Physics 2015-06-05 Alison J. Klesman , Vicki L. Sarajedini

We report the results of $g-$, $r-$, and $i-$dropout selections based on optical identifications of Very Large Array Sky Survey (VLASS) radio sources using the Hyper Suprime-Cam Subaru Strategic Program survey (HSC--SSP). By positional…

Modeling the spectral energy distribution (SED) of active galactic nuclei (AGN) plays a very important role in constraining modern cosmological simulations of galaxy formation. Here, we utilize an advanced supermassive black hole (SMBH)…

Astrophysics of Galaxies · Physics 2026-03-23 Tong Su , Qi Guo , Erlin Qiao , Wenxiang Pei , Luis C. Ho , Cedric G. Lacey

We report on the results of active galactic nuclei (AGNs) detection by NuSTAR performed in three extragalactic survey fields (COSMOS, UDS, ECDFS) in three hard bands, namely H1 (8-16 keV), H2 (16-24 keV) and VH (35-55 keV). The aggregated…

We present analysis of spectral energy distributions (SEDs) from mid-infrared through X-ray of a sample of 420 hard X-ray selected, z-band and Spitzer/IRAC detected active galactic nuclei (AGN) and AGN candidates from the GOODS…

ISO provides a key new far-infrared window through which to observe the multi-wavelength spectral energy distributions (SEDs) of quasars and active galactic nuclei (AGN). It allows us, for the first time, to observe a substantial fraction…

Reverberation mapping (RM) of active galactic nuclei (AGNs) has been used over the past three decades to determine AGN broad-line region (BLR) sizes and central black-hole masses, and their relations with the AGN's luminosity. Until…

Astrophysics of Galaxies · Physics 2021-06-03 Shai Kaspi , W. N. Brandt , Dan Maoz , Hagai Netzer , Donald P. Schneider , Ohad Shemmer , C. J. Grier
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