
<script type="text/javascript">
<!--
document.write('<div id="oa_widget"></div>');
document.write('<script type="text/javascript" src="https://www.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=undefined&type=result"></script>');
-->
</script>
Abstract We present the first event-horizon-scale images and spatiotemporal analysis of Sgr A* taken with the Event Horizon Telescope in 2017 April at a wavelength of 1.3 mm. Imaging of Sgr A* has been conducted through surveys over a wide range of imaging assumptions using the classical CLEAN algorithm, regularized maximum likelihood methods, and a Bayesian posterior sampling method. Different prescriptions have been used to account for scattering effects by the interstellar medium toward the Galactic center. Mitigation of the rapid intraday variability that characterizes Sgr A* has been carried out through the addition of a “variability noise budget” in the observed visibilities, facilitating the reconstruction of static full-track images. Our static reconstructions of Sgr A* can be clustered into four representative morphologies that correspond to ring images with three different azimuthal brightness distributions and a small cluster that contains diverse nonring morphologies. Based on our extensive analysis of the effects of sparse (u, v)-coverage, source variability, and interstellar scattering, as well as studies of simulated visibility data, we conclude that the Event Horizon Telescope Sgr A* data show compelling evidence for an image that is dominated by a bright ring of emission with a ring diameter of ∼50 μas, consistent with the expected “shadow” of a 4 × 106 M ⊙ black hole in the Galactic center located at a distance of 8 kpc.
Synthesis imaging, Black Holes, 330, Black hole, F520, Astronomy, F521, FOS: Physical sciences, 530, Event Horizon Telescope (EHT), [SDU] Sciences of the Universe [physics], Galactic center, High angular resolution, Very long baseline interferometry (VLBI), First Sagittarius A, 1769, Radio astronomy, Astronomical and space sciences, Aperture synthesis, Very long baseline interferometry, 162, 2167, High Energy Astrophysical Phenomena (astro-ph.HE), 53, Black holes, Astrophysical black holes, Space sciences, Astronomy and Astrophysics, 001, 98, Astrophysics - Astrophysics of Galaxies, 520, 565, [SDU]Sciences of the Universe [physics], Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astronomy & astrophysics, Astronomical sciences, 1338, Astrophysics - High Energy Astrophysical Phenomena, Mathematics
Synthesis imaging, Black Holes, 330, Black hole, F520, Astronomy, F521, FOS: Physical sciences, 530, Event Horizon Telescope (EHT), [SDU] Sciences of the Universe [physics], Galactic center, High angular resolution, Very long baseline interferometry (VLBI), First Sagittarius A, 1769, Radio astronomy, Astronomical and space sciences, Aperture synthesis, Very long baseline interferometry, 162, 2167, High Energy Astrophysical Phenomena (astro-ph.HE), 53, Black holes, Astrophysical black holes, Space sciences, Astronomy and Astrophysics, 001, 98, Astrophysics - Astrophysics of Galaxies, 520, 565, [SDU]Sciences of the Universe [physics], Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Astronomy & astrophysics, Astronomical sciences, 1338, Astrophysics - High Energy Astrophysical Phenomena, Mathematics
citations This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | 340 | |
popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network. | Top 0.1% | |
influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically). | Top 10% | |
impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network. | Top 0.01% |
views | 47 | |
downloads | 60 |