ALMA and VLA measurements of frequency-dependent time lags in Sagittarius A*: evidence for a relativistic outflow

2015/02/10 by Christiaan D. Brinkerink, Heino Falcke, H. Falcke +23 · 3 citations
Physics and Astronomy · #Accretion (finance) #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Cosmic Phenomena #Black hole (networking) #Flux (metallurgy) #Galaxy #Light curve #Optics #Outflow #Physics #Pulsars and Gravitational Waves Research #Sagittarius A* #Supermassive black hole #Very-long-baseline interferometry #Wavelength #astro-ph.GA #astro-ph.HE

paper · pdf · doi:10.1051/0004-6361/201424783

published as A&A 576, A41 (2015) · 10 pages, 9 figures. Accepted for publication in A&A. Updated acknowledgements

openalex publication_date 2015/02/10 · arxiv created 2015/02/12 · arxiv updated 2015/03/25 · openalex created_date 2020/11/23 · openalex updated_date 2026/08/05

Abstract

Context. Radio and mm-wavelength observations of Sagittarius A* (Sgr A*), the radio source associated with the supermassive black hole at the center of our Galaxy, show that it behaves as a partially self-absorbed synchrotron-emitting source. The measured size of Sgr A* shows that the mm-wavelength emission comes from a small region and consists of the inner accretion flow and a possible collimated outflow. Existing observations of Sgr A* have revealed a time lag between light curves at 43 GHz and 22 GHz, which is consistent with a rapidly expanding plasma flow and supports the presence of a collimated outflow from the environment of an accreting black hole.

Citations

• The Proper Motion of Sagittarius A*. II. The Mass of Sagittarius A*
• A size of ∼1 au for the radio source Sgr A* at the centre of the Milky Way
• Flaring Activity of Sagittarius A* at 43 and 22 GHz: Evidence for Expanding Hot Plasma
• SimultaneousChandra, CSO, and VLA Observations of Sgr A*: The Nature of Flaring Activity
• Viewing the Shadow of the Black Hole at the Galactic Center
• Measuring Distance and Properties of the Milky Way’s Central Supermassive Black Hole with Stellar Orbits
• The Nature of the 10 kilosecond X-ray flare in Sgr A*

Cited by

• The Size, Shape, and Scattering of Sagittarius A* at 86 GHz: First VLBI with ALMA
• Dynamical Imaging with Interferometry
• Multiwavelength Light Curves of Two Remarkable Sagittarius A* Flares