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Related papers: The AGN Optical Variability Fundamental Plane

200 papers

A supermassive black hole (SMBH) at the core of an active galactic nucleus (AGN) provides room for the elusive ultra-light scalar particles (ULSP) to be produced through a phenomenon called \textit{superradiance}. This phenomenon produces a…

High Energy Astrophysical Phenomena · Physics 2025-02-26 Priyanka Sarmah , Himanshu Verma , Kingman Cheung , Joseph Silk

We present results of our Power Spectral Density (PSD) analysis of 30 AGN using the 58 month light curves from Swift's Burst Alert Telescope (BAT) in the 14-150 keV band. PSDs were fit using a Monte Carlo based algorithm to take into…

High Energy Astrophysical Phenomena · Physics 2013-05-28 T. Taro Shimizu , Richard F. Mushotzky

Massive black-hole (MBH) binaries, which are expected to form following the merger of their parent galaxies, produce gravitational waves which will be detectable by Pulsar Timing Arrays at nanohertz frequencies (year periods). While no…

High Energy Astrophysical Phenomena · Physics 2019-03-13 Luke Zoltan Kelley , Zoltán Haiman , Alberto Sesana , Lars Hernquist

We report first-time reverberation mapping results for 14 AGNs from the ongoing Monitoring AGNs with H$\beta$ Asymmetry campaign (MAHA). These results utilize optical spectra obtained with the Long Slit Spectrograph on the Wyoming Infrared…

Recent studies of active galactic nuclei (AGN) found a statistical inverse linear scaling between the X-ray normalized excess variance $\sigma_{\rm rms}^2$ (variability amplitude) and the black hole mass spanning over $M_{\rm BH}=10^6-…

High Energy Astrophysical Phenomena · Physics 2015-06-26 Hai-Wu Pan , Weimin Yuan , Xin-Lin Zhou , Xiao-Bo Dong , Bifang Liu

The optically variable source SDSS J124602.54+011318.8 first appears in Sloan Digital Sky Survey (SDSS) data as a bright point source with nonstellar colors. Subsequent SDSS imaging and spectroscopy showed that the point source declined or…

Astrophysics · Physics 2009-11-07 Avishay Gal-Yam , Eran O. Ofek , Alexei V. Filippenko , Ryan Chornock , Weidong Li

We use the Sloan Digital Sky Survey (SDSS) Quasar Data Release 12 (DR12Q), containing nearly 300,000 AGNs, to calculate the monochromatic luminosities at 5100\AA, 3000\AA, and 1350\AA, derived from the broad-band extinction-corrected SDSS…

Astrophysics of Galaxies · Physics 2017-01-25 Szymon Kozłowski

Fifteen ROSAT PSPC observations available in the public archive are analyzed in order to study time and spectral variability of the 12 EMSS AGN detected by ROSAT with more than 2000 net counts. Time variability was investigated on 13…

Astrophysics · Physics 2007-05-23 Paolo Ciliegi , Tommaso Maccacaro

Despite the increasing number of Gravitational Wave (GW) detections, the astrophysical origin of Binary Black Hole (BBH) mergers remains elusive. A promising formation channel for BBHs is inside accretion discs around supermassive black…

High Energy Astrophysical Phenomena · Physics 2023-10-25 Niccolò Veronesi , Elena Maria Rossi , Sjoert van Velzen

This paper reports results of the third-year campaign of monitoring super-Eddington accreting massive black holes (SEAMBHs) in active galactic nuclei (AGNs) between 2014-2015. Ten new targets were selected from quasar sample of Sloan…

A sample of 10 nearby intermediate-type active galactic nuclei (AGN) drawn from the Sloan Digital Sky Survey (SDSS-DR7) is presented. The aim of this work is to provide estimations of the black hole mass for the sample galaxies from the…

In the innermost regions of Active Galactic Nuclei (AGN), matter is understood to be flowing onto the Supermassive black hole (SMBH), which forms an accretion disk. This disk is responsible for the optical/UV continuum emission observed in…

High Energy Astrophysical Phenomena · Physics 2023-08-01 Vivek Kumar Jha , Ravi Joshi , Jayesh Saraswat , Hum Chand , Sudhanshu Barway , Amit Kumar Mandal

It is well known that supermassive black holes (SMBHs) and their host galaxies co-evolve. AGN feedback plays an important role on this symbiosis. To study the effect of the AGN feedback on the host galaxy, a popular method is to study the…

Astrophysics of Galaxies · Physics 2023-12-06 George Mountrichas , Veronique Buat

We present the results of infrared K- (2.2 micron) and L'-band (3.8 micron) high-spatial-resolution (<0.2 arcsec) imaging observations of nearby gas- and dust-rich infrared luminous merging galaxies, assisted by the adaptive optics (AO)…

Astrophysics of Galaxies · Physics 2015-06-18 Masatoshi Imanishi , Yuriko Saito

The dependence of the long-term optical/UV variability on the spectral and the fundamental physical parameters for radio-quiet active galactic nuclei (AGNs) is investigated. The multi-epoch repeated photometric scanning data in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Y. L. Ai , W. Yuan , H. Y. Zhou , T. G. Wang , X. -B. Dong , J. G. Wang , H. L. Lu

We present a photometric search for objects with point-source components that are optically variable on timescales of weeks--months in the Hubble Ultra Deep Field (HUDF) to i'(AB)=28.0 mag. The data are split into four sub-stacks of…

We present the results from a detailed X-ray variability analysis of 66 AGN in the Lockman Hole, which have optical spectroscopic identifications. We compare, quantitatively, their variability properties with the properties of local AGN,…

The large-scale environments of active galactic nuclei (AGN) reveal important information on the growth and evolution of supermassive black holes (SMBHs). Previous AGN clustering measurements using 2-point correlation functions have hinted…

Astrophysics of Galaxies · Physics 2025-09-03 A. Mhatre , M. C. Powell , S. Yuan , S. W. Allen , T. Caglar , M. Koss , I. del Moral-Castro , K. Oh , A. Peca , C. Ricci , F. Ricci , A. Rojas , M. Signorini

We investigate the effect of active galactic nucleus (AGN) variability on the observed connection between star formation and black hole accretion in extragalactic surveys. Recent studies have reported relatively weak correlations between…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Ryan C. Hickox , James R. Mullaney , David M. Alexander , Chien-Ting J. Chen , Francesca M. Civano , Andy D. Goulding , Kevin N. Hainline

We present the first systematic study of short-timescale X-ray variability in radio-quiet active galactic nuclei (AGN), utilizing archival Chandra observations of approximately 3,000 broad-line AGN selected from the SDSS and DESI…

High Energy Astrophysical Phenomena · Physics 2025-12-09 Xiurui Zhao , Luca Comisso , Stefano Marchesi , Marco Ajello , Elias Kammoun , Yue Shen , Qiaoya Wu