English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  ALMA Observations of the Terahertz Spectrum of Sagittarius A

Bower, G. C., Dexter, J., Asada, K., Brinkerink, C. D., Falcke, H., Ho, P., et al. (2019). ALMA Observations of the Terahertz Spectrum of Sagittarius A. The Astrophysical Journal Letters, 881(1): L2. doi:10.3847/2041-8213/ab3397.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/21.11116/0000-0005-1942-5 Version Permalink: http://hdl.handle.net/21.11116/0000-0005-1960-3
Genre: Journal Article

Files

show Files
hide Files
:
ALMA Observations of the Terahertz Spectrum of Sagittarius A.pdf (Any fulltext), 2MB
 
File Permalink:
-
Name:
ALMA Observations of the Terahertz Spectrum of Sagittarius A.pdf
Description:
-
Visibility:
Private
MIME-Type / Checksum:
application/pdf
Technical Metadata:
Copyright Date:
-
Copyright Info:
-
License:
-

Locators

show

Creators

show
hide
 Creators:
Bower, Geoffrey C., Author
Dexter, Jason1, Author              
Asada, Keiichi, Author
Brinkerink, Christiaan D., Author
Falcke, Heino, Author
Ho, Paul, Author
Inoue, Makoto, Author
Markoff, Sera, Author
Marrone, Daniel P., Author
Matsushita, Satoki, Author
Moscibrodzka, Monika, Author
Nakamura, Masanori, Author
Peck, Alison, Author
Rao, Ramprasad, Author
Affiliations:
1Infrared and Submillimeter Astronomy, MPI for Extraterrestrial Physics, Max Planck Society, ou_159889              

Content

show
hide
Free keywords: -
 Abstract: We present Atacama Large Millimeter/submillimeter Array (ALMA) observations at 233, 678, and 870 GHz of the Galactic Center black hole, Sagittarius A*. These observations reveal a flat spectrum over this frequency range with spectral index α ≈ −0.3, where the flux density S ∝ ν α . We model the submillimeter and far-infrared spectrum with a one-zone synchrotron model of thermal electrons. We infer electron densities n = (2–5) × 106 cm−3, electron temperatures T e = (1–3) × 1011 K, and magnetic field strength B = 10–50 G. The parameter range can be further constrained using the observed quiescent X-ray luminosity. The flat submillimeter spectrum results in a high electron temperature and implies that the emitting electrons are efficiently heated. We also find that the emission is most likely optically thin at 233 GHz. These results indicate that millimeter and submillimeter wavelength very long baseline interferometry of Sgr A* including those of the Event Horizon Telescope should see a transparent emission region down to event horizon scales.

Details

show
hide
Language(s):
 Dates: 2019-08-05
 Publication Status: Published online
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Method: -
 Identifiers: DOI: 10.3847/2041-8213/ab3397
Other: LOCALID: 3176095
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: The Astrophysical Journal Letters
  Other : Astrophys. J. Lett.
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Chicago, IL : University of Chicago Press for the American Astronomical Society
Pages: - Volume / Issue: 881 (1) Sequence Number: L2 Start / End Page: - Identifier: ISSN: 2041-8205
CoNE: https://pure.mpg.de/cone/journals/resource/954922828215