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Detection of polarized mm and submm emission from SgrA*

D. K. Aitken·J. S. Greaves·A. Chrysostomou·W. S. Holland·J. H. Hough·D. Pierce-Price·J. S. Richer
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Abstract

We report the detection of linear polarization from SgrA* at 750, 850, 1350 and 2000 microns which confirms the contribution of synchrotron radiation. From the lack of polarization at longer wavelengths it appears to arise in the millimetre/sub-millimetre excess. There are large position angle changes between the millimetre and sub-millimetre results and these are discussed in terms of a polarized dust contribution in the sub-millimetre and various synchrotron models. In the model which best explains the data the synchrotron radiation from the excess is self-absorbed in the millimetre region and becomes optically thin in the sub-millimetre. This implies that the excess arises in an extremely compact source to the order of 2 Schwarzschild radii.

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D. K. Aitken, J. S. Greaves, A. Chrysostomou, W. S. Holland, J. H. Hough, D. Pierce-Price, J. S. Richer. 2000-03-24. Detection of polarized mm and submm emission from SgrA*. https://arxiv.org/abs/astro-ph/0003379

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