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Linear and Circular Polarization from Sagittarius A* and M81*

Geoffrey C. Bower
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Abstract

We describe recent results for Sgr A*, M81* and other low luminosity active galactic nuclei. We have conducted linear and circular polarimetry over a frequency range of 1.4 to 230 GHz and detected a variety of phenomena. The polarization properties of the studied sources are substantially different from higher powered AGN. In the case of Sgr A*, we are able to eliminate ADAFs and Bondi-Hoyle flows as possible models based on mm $λ$ polarimetry. Our success with Sgr A* demonstrates that we can learn about the nature of accretion and outflow in these sources with unprecedented detail. We may also develop probes of general relativity in the strong-field limit.

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Geoffrey C. Bower. 2003-02-11. Linear and Circular Polarization from Sagittarius A* and M81*. https://doi.org/10.1023/b%3Aastr.0000004995.36315.39

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