Results 41 to 50 of about 3,237 (137)

Modeling Targets and Optimal Frequencies for Imaging the Shadows of Nearby Supermassive Black Holes

The Astrophysical Journal
Horizon-scale imaging of supermassive black holes has opened a new avenue for studying strong-field gravity and plasma physics in low-luminosity accretion flows.
J. Cole Faggert, Feryal Özel, Dimitrios Psaltis   +2 more
doaj   +1 more source

Position determination of the Chang’e 3 lander with geodetic VLBI

Earth, Planets and Space, 2019
We present results from the analysis of observations of the Chang’e 3 lander using geodetic Very Long Baseline Interferometry. The applied processing strategy as well as the limiting factors to our approach is discussed.
Grzegorz Klopotek, Thomas Hobiger, Rüdiger Haas, Frédéric Jaron, Laura La Porta, Axel Nothnagel, Zhongkai Zhang, Songtao Han, Alexander Neidhardt, Christian Plötz   +9 more
doaj   +1 more source

Hyperspectral tomographic diffractive microscopy: Development and applications

Journal of Microscopy, EarlyView.
Abstract Tomographic Diffractive Microscopy (TDM) provides label‐free three‐dimensional imaging of transparent samples with resolution surpassing confocal limits. At IRIMAS, successive instrumental developments since 2009 have enhanced TDM capabilities through transmission, reflection, isotropic, polarisation‐sensitive, and dual‐view configurations ...
Leonardo Pestana Legori, Carlos Alberto Chacón Ávila, Matthieu Debailleul, Nicolas Verrier, Olivier Haeberlé   +4 more
wiley   +1 more source

Metrics of Astrometric Variability in the International Celestial Reference Frame. I. Statistical Analysis and Selection of the Most Variable Sources

The Astrophysical Journal Supplement Series
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 ...
Phil Cigan, Valeri V. Makarov, Nathan J. Secrest, David Gordon, Megan C. Johnson, Sebastien Lambert   +5 more
doaj   +1 more source

Seismic Velocity Variations Illustrate Hydrological and Ecohydrological Processes in a Mountain Watershed

Geophysical Research Letters, Volume 53, Issue 12, 28 June 2026.
Abstract We employ passive seismic interferometry to study seismic hydrological responses in a snowmelt‐driven, semi‐arid catchment. Seismic velocity changes (dv/v) at 2–4 Hz and 4–8 Hz are analyzed from six stations along a hillslope transect between May and November 2023 and compared to precipitation, soil moisture, and groundwater level timeseries ...
Kuan‐Fu Feng, Fan‐Chi Lin, Sara Warix, Paul D. Brooks, Qicheng Zeng, Tonie van Dam   +5 more
wiley   +1 more source

The Radio Fundamental Catalog. I. Astrometry

The Astrophysical Journal Supplement Series
We present an all-sky catalog of absolute positions and estimates of correlated flux density of 21,942 compact radio sources determined from processing interferometric visibility data of virtually all very long baseline interferometry (VLBI) observing ...
L. Y. Petrov, Y. Y. Kovalev
doaj   +1 more source

Multiwavelength Observations of Relativistic Jets from General Relativistic Magnetohydrodynamic Simulations

Galaxies, 2018
This work summarizes a program intended to unify three burgeoning branches of the high-energy astrophysics of relativistic jets: general relativistic magnetohydrodynamic (GRMHD) simulations of ever-increasing dynamical range, the microphysical theory of ...
Richard Anantua, Roger Blandford, Alexander Tchekhovskoy   +2 more
doaj   +1 more source

MSWD: A Hybrid Machine‐Learning Framework for Slant Wet Delay Modeling

Journal of Geophysical Research: Atmospheres, Volume 131, Issue 12, 28 June 2026.
Abstract Space geodetic techniques such as Global Navigation Satellite Systems (GNSS) and Very Long Baseline Interferometry (VLBI) are limited by direction‐dependent tropospheric delays, with slant wet delay (SWD) being the most variable component and a major error source.
Zhenyi Zhang, Benedikt Soja
wiley   +1 more source

Interseismic Creep Along the Enriquillo–Plantain Garden Fault, Haiti, Estimated From InSAR

Geophysical Research Letters, Volume 53, Issue 11, 16 June 2026.
Abstract The Enriquillo–Plantain Garden fault zone (EPGFZ) is a major left‐lateral strike‐slip fault in southern Haiti hosting several recent destructive earthquakes, including the 2021 MW 7.1 Nippes event with primary thrust‐slip. To investigate how strain is accommodated in the vicinity of the 2021 event, we analyzed Sentinel‐1 interferometric ...
Rishabh Dutta, Jeremy L. Maurer, Yi‐Chieh Lee   +2 more
wiley   +1 more source

Multifrequency Analysis of Favored Models for the Messier 87* Accretion Flow

The Astrophysical Journal
The polarized images of the supermassive black hole Messier 87* (M87*) produced by the Event Horizon Telescope (EHT) provide a direct view of the near-horizon emission from a black hole accretion and jet system.
Daniel C. M. Palumbo, Michi Bauböck, Charles F. Gammie   +2 more
doaj   +1 more source