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An Update on Monitoring Stellar Orbits in the Galactic Center
Using 25 years of data from uninterrupted monitoring of stellar orbits in the Galactic Center, we present an update of the main results from this unique data set: a measurement of mass and distance
First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
When surrounded by a transparent emission region, black holes are expected to reveal a dark shadow caused by gravitational light bending and photon capture at the event horizon. To image and study
A geometric distance measurement to the Galactic center black hole with 0.3% uncertainty
We present a 0.16% precise and 0.27% accurate determination of R0, the distance to the Galactic center. Our measurement uses the star S2 on its 16-year orbit around the massive black hole Sgr A* that
Dissecting X-ray–Emitting Gas Around the Center of Our Galaxy
X-ray observations of the center of the Galaxy reveal the interplay between the massive black hole there and its surroundings, and provide important constraints for models of the prevalent radiatively inefficient accretion state.
A public code for general relativistic, polarised radiative transfer around spinning black holes
Ray tracing radiative transfer is a powerful method for comparing theoretical models of black hole accretion flows and jets with observations. We present a public code, grtrans, for carrying out such
First M87 Event Horizon Telescope Results. VI. The Shadow and Mass of the Central Black Hole
We present measurements of the properties of the central radio source in M87 using Event Horizon Telescope data obtained during the 2017 campaign. We develop and fit geometric crescent models
Twelve years of spectroscopic monitoring in the Galactic Center: the closest look at S-stars near the black hole
We study the young S-stars within a distance of 0.04 pc from the supermassive black hole in the center of our Galaxy. Given how inhospitable the region is for star formation, their presence is more
Detection of the gravitational redshift in the orbit of the star S2 near the Galactic centre massive black hole
The highly elliptical, 16-year-period orbit of the star S2 around the massive black hole candidate Sgr A✻ is a sensitive probe of the gravitational field in the Galactic centre. Near pericentre at
The size of the jet launching region in M87
The supermassive black hole candidate at the centre of M87 drives an ultra-relativistic jet visible on kiloparsec scales, and its large mass and relative proximity allow for event horizon scale
We present the first systematic analysis of the X-ray variability of Sgr A ∗ during the Chandra X-ray Observatory’s 2012 Sgr A ∗ X-ray Visionary Project. With 38 High Energy Transmission Grating