275 citations · 1.7k across the 61 of their papers we have counts for
14 papers · 2 filters
NuSTAR Observes Two Bulgeless Galaxies: No Hard X-ray AGN Detected in NGC 4178 or J0851+3926
Ryan W. Pfeifle, Shobita Satyapal, Claudio Ricci +5
The discovery over the last several decades of moderate luminosity AGNs in disk-dominated galaxies - which show no "classical" bulges - suggests that secular mechanisms represent a…
CLASS Survey Description: Coronal Line Needles in the SDSS Haystack
Michael Reefe, Remington O. Sexton, Sara M. Doan +3
Coronal lines are a powerful, yet poorly understood, tool to identify and characterize Active Galactic Nuclei (AGNs). There have been few large scale surveys of coronal lines in th…
A Highly Magnified Gravitationally Lensed Red QSO at z = 2.5 with a Significant Flux Ratio Anomaly
Eilat Glikman, Cristian E. Rusu, Geoff C. -F. Chen +12
We present the discovery of a gravitationally lensed dust-reddened QSO at z = 2.517, identified in a survey for QSOs by infrared selection. Hubble Space Telescope imaging reveals a…
Nuclear Activity in the Low Metallicity Dwarf Galaxy SDSS J0944-0038: A Glimpse into the Primordial Universe
Michael Reefe, Shobita Satyapal, Remington O. Sexton +11
Local low metallicity dwarf galaxies are relics of the early universe and hold clues into the origins of supermassive black holes (SMBHs). In recent work, coronal lines have been u…
A catalog of candidate double and lensed quasars from Gaia and WISE data
Valeri V. Makarov, Nathan J. Secrest
Making use of strong correlations between closely separated multiple or double sources and photometric and astrometric metadata in Gaia EDR3, we generate a catalog of candidate dou…
Optical-Radio Position Offsets are Inversely Correlated with AGN Photometric Variability
Nathan Secrest
Using photometric variability information from the new Gaia DR3 release, I show for the first time that photometric variability is inversely correlated with the prevalence of optic…
CLASS: Coronal Line Activity Spectroscopic Survey
Michael Reefe, Shobita Satyapal, Remington O. Sexton +3
We conduct the first systematic survey of a comprehensive set of the twenty optical coronal lines in the spectra of nearly 1 million galaxies observed by the Sloan Digital Sky Surv…
Fundamental Reference AGN Monitoring Experiment (FRAMEx) III: Radio Emission in the Immediate Vicinity of Radio Quiet AGNs
Onic I. Shuvo, Megan C. Johnson, Nathan J. Secrest +5
We present follow-up results from the first Fundamental Reference AGN Monitoring Experiment (FRAMEx) X-ray/radio snapshot program of a volume-complete sample of local hard X-ray-se…
Quasars with Proper Motions and the Link to Double and Multiple AGNs
Valeri V. Makarov, Nathan J. Secrest
Gaia used a large sample of photometrically selected active galactic nuclei (AGNs) and quasars to remove the residual spin of its global proper motion system in order to achieve a…
Wandering Black Hole Candidates in Dwarf Galaxies at VLBI Resolution
Andrew J. Sargent, Megan C. Johnson, Amy E. Reines +5
Thirteen dwarf galaxies have recently been found to host radio-selected accreting massive black hole (MBH) candidates, some of which are ``wandering" in the outskirts of their host…
Galaxy Pairs in the Sloan Digital Sky Survey XV: Properties of Ionised Outflows
William Matzko, Shobita Satyapal, Sara L. Ellison +6
Powerful outflows are thought to play a critical role in galaxy evolution and black hole growth. We present the first large-scale systematic study of ionised outflows in paired gal…
The U.S. Naval Observatory VLBI Spectroscopic Catalog
Remington O. Sexton, Nathan J. Secrest, Megan C. Johnson +1
Despite their importance for astrometry and navigation, the active galactic nuclei (AGNs) that comprise the International Celestial Reference Frame (ICRF) are relatively poorly und…
Testing the Cosmological Principle: Astrometric Limits on Systemic Motion of Quasars at Different Cosmological Epochs
Valeri V. Makarov, Nathan J. Secrest
A sample of bona fide optical quasars with astrometric proper motions in Gaia EDR3 and spectroscopic redshifts above 0.5 in an oval 8400 square degree area of the sky is c…
FRAMEx II: Simultaneous X-ray and Radio Variability in Active Galactic Nuclei The Case of NGC 2992
Luis C. Fernandez, Nathan J. Secrest, Megan C. Johnson +4
Using simultaneous Very Long Baseline Array and Neil Gehrels Swift Observatory X-ray Telescope observations of the active galactic nucleus (AGN) in NGC 2992 over a six-month observ…