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How to hide large scale outflows: size constraints on the jets of Sgr A*

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 نشر من قبل Sera Markoff
 تاريخ النشر 2007
  مجال البحث فيزياء
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Despite significant strides made towards understanding accretion, outflow, and emission processes in the Galactic Center supermassive black hole Sagittarius A*, the presence of jets has neither been rejected nor proven. We investigate here whether the combined spectral and morphological properties of the source at radio through near infrared wavelengths are consistent with the predictions for inhomogeneous jets. In particular, we construct images of jets at a wavelength of 7mm based on models that are consistent with the spectrum of Sgr A*. We then compare these models through closure quantities with data obtained from the Very Long Baseline Array at 7mm. We find that the best-fit jet models give comparable or better fits than best-fit Gaussian models for the intrinsic source found in previous analyses. The best fitting jet models are bipolar, are highly inclined to the line of sight ($theta ge$ 75 degrees), may favor a position angle on the sky of 105 degrees, and have compact bases with sizes of a few gravitational radii.



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