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This work focuses on active galactic nuclei (AGNs), and the relation between the sizes of the hot dust continuum and the broad-line region (BLR). We find that the continuum size measured using optical/near-infrared interferometry (OI) is…

We present a revised analysis of the photometric reverberation mapping campaign of the narrow-line Seyfert 1 galaxy PKS 0558-504 carried out with the Swift Observatory during 2008--2010. Previously, Gliozzi et al.\ found using the Discrete…

Information on the structure around active galactic nuclei (AGN) has long been derived from measuring lags in their varying light output at different wavelengths. In principle, infrared data would reach to larger radii, potentially even…

Astrophysics of Galaxies · Physics 2021-03-17 E. Elmer , M. Merrifield , O. Almaini , W. G. Hartley , D. T. Maltby

We developed a spectroscopic monitoring project to investigate the kinematics of the broad-line region (BLR) in active galactic nuclei (AGN) with ultra-fast outflows (UFOs). Mrk~79 is a radio-quiet AGN with UFOs and warm absorbers, had been…

We use quasi-simultaneous near-infrared (near-IR) and optical spectroscopy from four observing runs to study the continuum around 1 micron in 23 well-known broad-emission line active galactic nuclei (AGN). We show that, after correcting the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Hermine Landt , Martin Elvis , Martin J. Ward , Misty C. Bentz , Kirk T. Korista , Margarita Karovska

We compiled a sample of 73 active galactic nuclei (AGNs) with reverberation mapping (RM) observations from RM campaigns including our ongoing campaign of monitoring super-Eddington accreting massive black holes (SEAMBHs). This sample covers…

We present the Granger causality (GC) test for the X-ray reverberation analysis of Active Galactic Nuclei (AGN). If the light curves in the continuum-dominated band help predict (Granger cause) those dominated by reflection, the Granger…

High Energy Astrophysical Phenomena · Physics 2024-04-09 N. Nakhonthong , P. Chainakun , W. Luangtip , A. J. Young

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…

Astrophysics · Physics 2009-11-10 K. Nandra , E. S. Laird , C. C. Steidel

Active Galactic Nuclei (AGN) sources feature supermassive black holes that launch relativistic plasma jets. They are key $\gamma$-ray sources providing a unique laboratory for studying extreme particle acceleration and plasma physics.…

High Energy Astrophysical Phenomena · Physics 2026-02-03 Luana Passos-Reis , Elisabete M. de Gouveia Dal Pino , Tarek Hassan , Santiago Pita , Alberto Domínguez

We present 1.8 years of near-daily Swift monitoring of the bright, strongly variable Type 1 AGN Fairall 9. Totaling 575 successful visits, this is the largest such campaign reported to date. Variations within the UV/optical are…

High Energy Astrophysical Phenomena · Physics 2024-07-15 R. Edelson , B. M. Peterson , J. Gelbord , K. Horne , M. Goad , I. McHardy , S. Vaughan , M. Vestergaard

Active galactic nuclei (AGN) have been observed to vary stochastically with 10-20 rms amplitudes over a range of optical wavelengths where the emission arises in an accretion disk. Since the accretion disk is unlikely to vary coherently,…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-04 Jason Dexter , Eric Agol

Changing-look active galactic nucleus NGC~4151, which has attracted a lot of attention, is undergoing the second dramatic outburst stage in its evolutionary history. To investigate the geometry and kinematics of the broad-line region (BLR),…

Astrophysics of Galaxies · Physics 2022-09-07 Sha-Sha Li , Hai-Cheng Feng , H. T. Liu , J. M. Bai , Rui Li , Kai-Xing Lu , Jian-Guo Wang , Ying-Ke Huang , Zhi-Xiang Zhang

We present the results of a continuum reverberation mapping study of the radio-quiet Seyfert 1 galaxy IRAS 09149-6206. The analysis was performed using X-ray, UV and optical observations made with the {\em Swift} telescope between January…

High Energy Astrophysical Phenomena · Physics 2023-08-11 D. H. González-Buitrago , Ma. T. García-Díaz , F. Pozo Nuñez , Hengxiao Guo

Reverberation mapping is now a well-established technique for investigating spatially-unresolved structures in the nuclei of distant galaxies with actively-accreting supermassive black holes. Structural parameters for the broad…

Astrophysics of Galaxies · Physics 2020-09-09 Misty C. Bentz

Optical observations cannot resolve the structure of active galactic nuclei (AGN), and a unified model for AGN was inferred mostly from indirect methods. Optical reverberation mapping allowed us to constrain the spatial dimension of the…

High Energy Astrophysical Phenomena · Physics 2017-12-05 P. A. Rojas Lobos , R. W. Goosmann , F. Marin , D. Savić

NGC 2617 has attracted a lot of attention after the detection of the changes in spectral type, and its geometry and kinematics of broad-line region (BLR) are still ambiguous. In this paper, we present the high cadence ($\sim$ 2 days)…

Astrophysics of Galaxies · Physics 2021-05-19 Hai-Cheng. Feng , H. T. Liu , J. M. Bai , Zi-Xu. Yang , Chen. Hu , Sha-Sha. Li , Sen. Yang , Kai-Xing. Lu , Ming. Xiao

We present the first results from the ongoing, intensive, multi-wavelength monitoring program of the luminous Seyfert 1 galaxy Mrk 817. While this AGN was, in part, selected for its historically unobscured nature, we discovered that the…

We have recently completed a 64-night spectroscopic monitoring campaign at the Lick Observatory 3-m Shane telescope with the aim of measuring the masses of the black holes in 12 nearby (z < 0.05) Seyfert 1 galaxies with expected masses in…