405 citations · 1.3k across the 30 of their papers we have counts for
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The Importance of Co-located VLBI Intensive Stations and GNSS Receivers: A case study of the Maunakea VLBI and GNSS stations during the 2018 Hawai`i earthquake
Christopher Dieck, Megan C. Johnson, Daniel S. MacMillan
Frequent, low-latency measurements of the Earth's rotation phase, UT1UTC, critically support the current estimate and short-term prediction of this highly variable Earth Orienta…
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…
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…
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…
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…