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Related papers: Variable AGN in the GALEX Time Domain Survey

200 papers

We investigated AGN activity in low-mass galaxies, an important regime that can shed light onto BH formation and evolution, and their interaction with their host galaxies. We identified 336 AGN candidates from a parent sample of $\sim…

This work makes use of the VST observations to select variable sources. We use also the IR photometry, SED fitting and X-ray information where available to confirm the nature of the AGN candidates. The IR data, available over the full…

To investigate the population of massive black holes in dwarf galaxies, we conduct a systematic search for active galactic nuclei (AGNs) using data from the first data release of the eROSITA All-Sky Survey (eRASS1). We crossmatch dwarf…

Astrophysics of Galaxies · Physics 2025-09-30 John-Michael Eberhard , Amy E. Reines

We present a census of local active galactic nuclei (AGN) at a redshift of $z\leq0.025$ selected using the high-ionization [Ne v] $\lambda14.32\,\mu$m emission line from the Infrared Database of Extragalactic Observables from Spitzer…

Astrophysics of Galaxies · Physics 2026-03-16 S. Yassir , A. Annuar

Active galactic nuclei (AGN) are supermassive black holes with luminous accretion disks found in some galaxies, and are thought to play an important role in galaxy evolution. However, traditional optical spectroscopy for identifying AGN…

Astrophysics of Galaxies · Physics 2022-12-16 Ziting Guo , John F. Wu , Chelsea E. Sharon

With upcoming all sky surveys such as LSST poised to generate a deep digital movie of the optical sky, variability-based AGN selection will enable the construction of highly-complete catalogs with minimum contamination. In this study, we…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-27 Yumi Choi , Robert R. Gibson , Andrew C. Becker , Željko Ivezić , Andrew J. Connolly , Chelsea L. MacLeod , John J. Ruan , Scott F. Anderson

We present a systematic search for radio active galactic nuclei (AGNs) in dwarf galaxies using recent observations taken by the Very Large Array Sky Survey (VLASS). To select these objects, we first establish a criterion to identify…

Astrophysics of Galaxies · Physics 2024-11-25 John-Michael Eberhard , Amy E. Reines , Hansung B. Gim , Jeremy Darling , Jenny E. Greene

Variability is a property shared by practically all AGN. This makes variability selection a possible technique for identifying AGN. Given that variability selection makes no prior assumption about spectral properties, it is a powerful…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Carolin Villforth , Anton M. Koekemoer , Norman A. Grogin

We classify the spectral energy distributions (SEDs) of 431,038 sources in the 9 sq. deg Bootes field of the NOAO Deep Wide-Field Survey (NDWFS). There are up to 17 bands of data available per source, including ultraviolet (GALEX), optical…

In this work, we use 8 years of deep near-infrared imaging to select and study a new set of 601 active galaxies identified through long-term near-infrared (NIR) variability in the UKIDSS Ultra Deep Survey (UDS). These objects are compared…

Astrophysics of Galaxies · Physics 2024-05-24 K. Green , E. Elmer , D. T. Maltby , O. Almaini , M. Merrifield , W. G. Hartley

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…

Astrophysics · Physics 2007-05-23 W. Pietsch , Th. Boller , S. Doebereiner , H. -U. Zimmermann , K. Bischoff , W. Kollatschny

The morphological study is crucial to investigate the connections between active galactic nuclei (AGN) activities and the evolution of galaxies. Substantial studies have found that radiative-mode AGNs primarily reside in disk galaxies,…

Astrophysics of Galaxies · Physics 2022-02-09 Yuxing Zhong , Akio K. Inoue , Satoshi Yamanaka , Toru Yamada

While there are numerous criteria for photometrically identifying active galactic nuclei (AGNs), searches in the optical and UV tend to exclude galaxies that are highly dust obscured. This is problematic for constraining models of AGN…

Astrophysics of Galaxies · Physics 2018-07-17 Anson Lam , Edward L. Wright , Matthew A. Malkan

We study the black hole mass $-$ host galaxy stellar mass relation, $M_{\rm{BH}}-M_{\ast}$, for a sample of 706 $z \lesssim 1.5$ and $i \lesssim 24$ optically-variable active galactic nuclei (AGNs) in three Dark Energy Survey (DES) deep…

Astrophysics of Galaxies · Physics 2025-03-11 Yichen Liu , Colin J. Burke , Diego Miura , Xin Liu , Qian Yang , Priyamvada Natarajan , Charlotte A. Ward

We present a spectroscopic and photometric analysis of a sample of 416,288 galaxies from the Sloan Digital Sky Survey (SDSS) matched to mid-infrared (mid-IR) data from the Wide-Field Infrared Survey Explorer (WISE). By using a new…

Astrophysics of Galaxies · Physics 2022-04-27 Raphael E. Hviding , Kevin N. Hainline , Marcia Rieke , Stéphanie Juneau , Jianwei Lyu , Ragadeepika Pucha

Context. Active galactic nuclei (AGN) of galaxies play an important role in the life and evolution of galaxies due to the impact they exert on certain properties and the evolutionary path of galaxies. It is well known that infrared (IR)…

Astrophysics of Galaxies · Physics 2022-08-24 Carlos G. Bornancini , Gabriel A. Oio , M. Victoria Alonso , Diego García Lambas

X-ray emission detection in a galaxy is one of the efficient tools for selecting Active Galactic Nuclei (AGNs). However, many X-ray-selected AGNs are not easily selected as AGNs by their optical emission. These galaxies, so-called optically…

Astrophysics of Galaxies · Physics 2022-03-31 Itsna K. Fitriana , Takashi Murayama

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…

Astrophysics of Galaxies · Physics 2025-03-25 S. Bernal , P. Sánchez-Sáez , P. Arévalo , F. E. Bauer , P. Lira , B. Sotomayor

We present a detailed study of the optical spectroscopic properties of 12 active galactic nuclei (AGNs) with candidate low-mass black holes (BHs) selected by Kamizasa et al. through rapid X-ray variability. The high-quality, echellette…

Astrophysics of Galaxies · Physics 2016-04-20 Luis Ho , Minjin Kim

We analyze the wavelength-dependent variability of a sample of spectroscopically confirmed active galactic nuclei (AGN) selected from near-UV ($NUV$) variable sources in the GALEX Time Domain Survey that have a large amplitude of optical…

High Energy Astrophysical Phenomena · Physics 2016-12-28 T. Hung , S. Gezari , D. O. Jones , R. P. Kirshner , R. Chornock , E. Berger , A. Rest , M. Huber , G. Narayan , D. Scolnic , C. Waters , R. Wainscoat , D. C. Martin , K. Forster , J. D. Neill