activity
20232026
most citedTowards a complete census of luminous Compton-thick Active Galactic Nuclei in the local Universe

9 citations · 27 across the 10 of their papers we have counts for

collaborators

11 papers

astro-ph.GA2026

A Decade-Scale Ionization Echo of Black-Hole Accretion in Galactic Nuclei

Wei-Jian Guo, Shuo Zhai, Chen Hu +16

Circumnuclear structures in active galactic nuclei respond to accretion variability over different spatial and temporal scales, but whether compact narrow-line gas responds on deca…

astro-ph.GA2026

A striking excess of red quasars with steep radio spectral slopes: a dusty blow-out phase revealed through AGN-driven shocks?

Ciera L. Sargent, David M. Alexander, Claire L. Greenwell +5

Red quasars exhibit a higher incidence of compact (galaxy-scale or smaller) radio emission than blue quasars, arising from systems near the radio-loud/radio-quiet threshold. In thi…

astro-ph.GA2025

Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. IV. Broad Emission Line Evolution Sequence Among Hα, Mg II, and Hβ

Wei-Jian Guo, Victoria A. Fawcett, Małgorzata Siudek +15

From a parent catalog of 561 changing-look active galactic nuclei (CL-AGNs) identified by Guo et al. (2025), we investigate the evolutionary sequence of broad emission lines using…

astro-ph.GA2025

An obscured quasar census with the 4MOST IR AGN survey: design, predicted properties, and scientific goals

Carolina Andonie, David M. Alexander, Claire Greenwell +11

We present the 4MOST IR AGN survey, the first large-scale optical spectroscopic survey characterizing mid-infrared (MIR) selected obscured active galactic nuclei (AGN). The survey…

astro-ph.HE2025★ 7 cited

AT 2018dyk: tidal disruption event or active galactic nucleus? Follow-up observations of an extreme coronal line emitter with the Dark Energy Spectroscopic Instrument

Peter Clark, Joseph Callow, Or Graur +29

We present fresh insights into the nature of the tidal disruption event (TDE) candidate AT 2018dyk. AT 2018dyk has sparked a debate in the literature around its classification as e…

astro-ph.GA2024★ 1 cited

The NuSTAR Local AGN Distribution Survey (NuLANDS) I: Towards a Truly Representative Column Density Distribution in the Local Universe

Peter G. Boorman, Poshak Gandhi, Johannes Buchner +33

Hard X-ray-selected samples of Active Galactic Nuclei (AGN) provide one of the cleanest views of supermassive black hole accretion, but are biased against objects obscured by Compt…

astro-ph.GA2024★ 9 cited

Towards a complete census of luminous Compton-thick Active Galactic Nuclei in the local Universe

A. Akylas, I. Georgantopoulos, P. Gandhi +2

X-ray surveys provide the most efficient means for the detection of Active Galactic Nuclei (AGN). However, they face difficulties in detecting the most heavily obscured Compton-thi…

astro-ph.GA2024★ 3 cited

Changing-look Active Galactic Nuclei from the Dark Energy Spectroscopic Instrument. II. Statistical Properties from the First Data Release

Wei-Jian Guo, Hu Zou, Claire L. Greenwell +33

We present the identification of changing-look active galactic nuclei (CL-AGNs) from the Dark Energy Spectroscopic Instrument First Data Release and Sloan Digital Sky Survey Data R…

astro-ph.HE2024

The NuSTAR Serendipitous Survey: the 80-month catalog and source properties of the high-energy emitting AGN and quasar population

Claire L. Greenwell, Lizelke Klindt, George B. Lansbury +32

We present a catalog of hard X-ray serendipitous sources detected in the first 80 months of observations by the Nuclear Spectroscopic Telescope Array (NuSTAR). The NuSTAR serendipi…

astro-ph.GA2024★ 7 cited

A population of Optically Quiescent Quasars from WISE and SDSS

Claire Greenwell, Poshak Gandhi, Daniel Stern +4

The growth of active galactic nuclei (AGN) occurs under some form of obscuration in a large fraction of the population. The difficulty in constraining this population leads to high…

astro-ph.GA2023

Obscuration beyond the nucleus: infrared quasars can be buried in extreme compact starbursts

Carolina Andonie, David M. Alexander, Claire Greenwell +14

In the standard quasar model, the accretion disk obscuration is due to the canonical dusty torus. Here, we argue that a substantial part of the quasar obscuration can come from the…