Zobrazeno 1 - 10
of 53
pro vyhledávání: '"Megan C. Johnson"'
Autor:
Phil Cigan, Valeri V. Makarov, Nathan J. Secrest, David Gordon, Megan C. Johnson, Sebastien Lambert
Publikováno v:
The Astrophysical Journal Supplement Series, Vol 274, Iss 2, p 28 (2024)
Using very long baseline interferometry data for the sources that comprise the third International Celestial Reference Frame (ICRF3), we examine the quality of the formal source-position uncertainties of ICRF3 by determining the excess astrometric va
Externí odkaz:
https://doaj.org/article/6265c1a4e3a043b5a96f719e970e4114
Autor:
Andrew J. Sargent, Travis C. Fischer, Megan C. Johnson, Alexander J. van der Horst, Nathan J. Secrest, Onic I. Shuvo, Phil J. Cigan, Krista L. Smith
Publikováno v:
The Astrophysical Journal, Vol 961, Iss 2, p 230 (2024)
We present the first results from Karl G. Jansky Very Large Array (VLA) observations as a part of the Fundamental Reference Active Galactic Nucleus (AGN) Monitoring Experiment, a program to understand the relationship between AGN accretion physics an
Externí odkaz:
https://doaj.org/article/3abf42d3697f4a65adf859726194629b
Autor:
Onic I. Shuvo, Megan C. Johnson, Nathan J. Secrest, Mario Gliozzi, Phillip J. Cigan, Travis C. Fischer, Alexander J. Van Der Horst
Publikováno v:
The Astrophysical Journal, Vol 961, Iss 1, p 109 (2024)
We present results from the Very Long Baseline Array multifrequency (1.6, 4.4, 8.6, and 22 GHz), high-sensitivity (∼25 μ Jy beam ^−1 ), subparsec-scale (
Externí odkaz:
https://doaj.org/article/2e080e9fca87497ea95d5d0fbf402c32
Publikováno v:
The Astrophysical Journal, Vol 958, Iss 1, p 61 (2023)
Using the Very Long Baseline Array, we observed the active galactic nucleus (AGN) in NGC 3079 over a span of six months to test for variability in the two main parsec-scale radio components, A and B , which lie on either side of the AGN. We found evi
Externí odkaz:
https://doaj.org/article/391d500eedd5403d80a972daa1307e66
Autor:
Travis C. Fischer, Megan C. Johnson, Nathan J. Secrest, D. Michael Crenshaw, Steven B. Kraemer
Publikováno v:
The Astrophysical Journal, Vol 953, Iss 1, p 87 (2023)
We present recent Very Long Baseline Array (VLBA) 5 GHz radio observations of the nearby, luminous Seyfert 2 galaxy NGC 1068 for comparison to similar VLBA observations made on 1997 April 26. By cross-correlating the positions of emitting regions acr
Externí odkaz:
https://doaj.org/article/c9425dc8800848ce8711d4446f16ab95
Publikováno v:
The Astronomical Journal, Vol 166, Iss 1, p 8 (2023)
The fundamental celestial reference frame (CRF) is based on two catalogs of astrometric positions: the third realization of the International Celestial Reference Frame (ICRF3), and the much larger Gaia CRF, built from the third data release (DR3). Th
Externí odkaz:
https://doaj.org/article/39b19b09471748c3a57a8568cf6d7d35
Autor:
Elizabeth M. Rosenthal, James M. Tesoriero, Susan M. Flavin, Yingchao Yuan, Thomas T. Sullivan, Megan C. Johnson
Publikováno v:
Journal of Public Health Management and Practice. 29:336-344
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::e644560c10ee7cff103777f554e1f793
https://doi.org/10.1097/phh.0000000000001700
https://doi.org/10.1097/phh.0000000000001700
Frequent, low-latency measurements of the Earth's rotation phase, UT1$-$UTC, critically support the current estimate and short-term prediction of this highly variable Earth Orientation Parameter (EOP). Very Long Baseline Interferometry (VLBI) Intensi
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9782558a6262f33f40b0af481eac7fac
http://arxiv.org/abs/2212.03453
http://arxiv.org/abs/2212.03453
Publikováno v:
Journal of Public Health Management and Practice
Supplemental Digital Content is Available in the Text.
Context: Gay, bisexual, and men who have sex with men (MSM) are disproportionately affected by the HIV/AIDS epidemic more than any other group. In New York State (NYS) outside of New York Ci
Context: Gay, bisexual, and men who have sex with men (MSM) are disproportionately affected by the HIV/AIDS epidemic more than any other group. In New York State (NYS) outside of New York Ci
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::e91bdedc7efd933fe76c67ff852e1fed
https://doi.org/10.1097/phh.0000000000001138
https://doi.org/10.1097/phh.0000000000001138
Autor:
Luis C. Fernandez, Nathan J. Secrest, Megan C. Johnson, Henrique R. Schmitt, Travis C. Fischer, Phillip J. Cigan, Bryan N. Dorland
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 observing campaign, we observed a large drop in core 5 cm radio luminosity,
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::acc0d72dad7ec7e73d0507f3f7081c18