中文
相关论文

相关论文: The OPTX Project V: Identifying Distant AGNs

200 篇论文

We investigated the influence of Active Galactic Nuclei (AGN) feedback on star formation in red spiral galaxies by analyzing a sample of 324 red and 273 blue face-on spirals selected from 115 low-redshift galaxy clusters. This…

As the mid-IR luminosity represents a good isotropic proxy of the AGN power, a low X-ray to mid-IR luminosity ratio is often claimed to be a reliable indicator for selecting Compton-thick (CT) AGN. We assess the efficiency of this…

宇宙学与河外天体物理 · 物理学 2015-05-28 I. Georgantopoulos , E. Rovilos , A. Akylas , A. Comastri , P. Ranalli , C. Vignali , I. Balestra , R. Gilli , N. Cappelluti

We used random forest algorithms to classify all objects in a large portion of the sky, using optical light curves obtained, or built from images provided, by the Zwicky Transient Facility (ZTF). We compare different selection sets based on…

星系天体物理 · 物理学 2025-03-25 S. Bernal , P. Sánchez-Sáez , P. Arévalo , F. E. Bauer , P. Lira , B. Sotomayor

Heavily obscured accretion is believed to represent an important stage in the growth of supermassive black holes, and to play an important role in shaping the observed spectrum of the Cosmic X-ray Background (CXB). Hard X-ray (E$>$10 keV)…

高能天体物理现象 · 物理学 2017-03-29 C. Ricci , Y. Ueda , M. J. Koss , B. Trakhtenbrot , F. E. Bauer , P. Gandhi

The Swift Burst Alert Telescope (BAT) survey of Active Galactic Nuclei (AGN) is providing an unprecedented view of local AGNs (<z> = 0.03) and their host galaxy properties. In this paper, we present an analysis of the optical spectra of a…

宇宙学与河外天体物理 · 物理学 2015-05-14 Lisa M. Winter , Karen T. Lewis , Michael Koss , Sylvain Veilleux , Brian Keeney , Richard F. Mushotzky

Through an optical campaign performed at 4 telescopes located in the northern and the southern hemispheres, we have obtained optical spectroscopy for 75 counterparts of unclassified or poorly studied hard X-ray emitting objects detected…

Active Galactic Nuclei (AGN) produce a dominant fraction (~80%) of the Soft X-ray background (SXB) at photon energies 0.5<E<2 keV. If dust pervaded throughout the intergalactic medium, its scattering opacity would have produced diffuse…

宇宙学与河外天体物理 · 物理学 2015-05-13 Mark Dijkstra , Abraham Loeb

We investigate the physical conditions of ionized gas in high-z star-forming galaxies using diagnostic diagrams based on the rest-frame optical emission lines. The sample consists of 701 galaxies with an Ha detection at $1.4\lesssim…

The James Webb Space Telescope (JWST) is revolutionizing our understanding of black holes formation and growth in the early Universe. However, JWST has also revealed that some of the classical diagnostics, such as the BPT diagrams and X-ray…

星系天体物理 · 物理学 2024-11-27 G. Mazzolari , H. Übler , R. Maiolino , X. Ji , K. Nakajima , A. Feltre , J. Scholtz , F. D'Eugenio , M. Curti , M. Mignoli , A. Marconi

We present an analysis of near-infrared (NIR) emission-line properties, AGN diagnostics, and circumnuclear gas dynamics for 453 hard X-ray selected (14$-$195 keV) AGN from the BAT AGN Spectroscopic Survey (BASS) NIR Data Release 3 (DR3;…

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…

星系天体物理 · 物理学 2025-12-04 Caroline Baccus , Xinfeng Xu

We investigate the possibility of using the ratio between the 2-10 keV flux and the [Ne V]3426 emission line flux (X/NeV) as a diagnostic diagram to discover heavily obscured, possibly Compton-Thick Active Galactic Nuclei (AGN) up to z~1.5.…

宇宙学与河外天体物理 · 物理学 2015-05-18 R. Gilli , C. Vignali , M. Mignoli , K. Iwasawa , A. Comastri , G. Zamorani

In order to understand the interactions between active galactic nuclei (AGN) and star formation during the evolution of galaxies, we investigate 142 galaxies detected in both X-ray and 70{\mu}m observations in the COSMOS (Cosmic Evolution…

宇宙学与河外天体物理 · 物理学 2016-02-23 Ming-Yi Lin , Yasuhiro Hashimoto , Sebastien Foucaud

We compute synthetic, rest-frame optical and ultraviolet (UV) emission-line properties of galaxy populations at redshifts from z$\approx$0 to z=8 in a full cosmological framework. We achieve this by coupling, in post-processing, the…

The obscured accretion phase in BH growth is a key ingredient in many models linking the AGN activity with the evolution of their host galaxy. At present, a complete census of obscured AGN is still missing. The purpose of this work is to…

高能天体物理现象 · 物理学 2014-11-05 C. Vignali , M. Mignoli , R. Gilli , A. Comastri , K. Iwasawa , G. Zamorani , V. Mainieri , A. Bongiorno

We present Spitzer 7-38um spectra for a 24um flux limited sample of galaxies at z~0.7 in the COSMOS field. The detailed high-quality spectra allow us to cleanly separate star formation (SF) and active galactic nucleus (AGN) in individual…

We present a coherent database of spectroscopic observations of far-IR fine-structure lines from the Herschel/PACS archive for a sample of 170 local AGN, plus a comparison sample of 20 starburst galaxies and 43 dwarf galaxies. Published…

We present the first results of a program to identify so far unknown active nuclei (AGN) in galaxies. Candidate galactic nuclei have been selected for optical spectroscopy from a cross-correlation of the ROSAT All Sky Survey (RASS) bright…

天体物理学 · 物理学 2007-05-23 W. Pietsch , Th. Boller , S. Doebereiner , H. -U. Zimmermann , K. Bischoff , W. Kollatschny

Compton-thick active galactic nuclei (CT-AGNs), which are defined by column density $\mathrm{N_H} \geqslant 1.5 \times 10^{24} \ \mathrm{cm}^{-2}$, emit feeble X-ray radiation, even undetectable by X-ray instruments. Despite this, the X-ray…

星系天体物理 · 物理学 2025-05-28 Rui Zhang , Xiaotong Guo , Qiusheng Gu , Guanwen Fang , Jun Xu , Hai-Cheng Feng , Yongyun Chen , Rui Li , Nan Ding , Hongtao Wang