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arXiv · 1301.3906

Radio light curves during the passage of cloud G2 near Sgr A*

A. Sadowski·L. Sironi·D. Abarca·X. Guo·F. Ozel·R. Narayan
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Abstract

We calculate radio light curves produced by the bow shock that is likely to form in front of the G2 cloud when it penetrates the accretion disk of Sgr A*. The shock acceleration of the radio-emitting electrons is captured self-consistently by means of first-principles particle-in-cell simulations. We show that the radio luminosity is expected to reach maximum in early 2013, roughly a month after the bow shock crosses the orbit pericenter. We estimate the peak radio flux at 1.4 GHz to be 1.4 - 22 Jy depending on the assumed orbit orientation and parameters. We show that the most promising frequencies for radio observations are in the 0.1<nu<1 GHz range, for which the bow shock emission will be much stronger than the intrinsic radio flux for all the models considered.

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A. Sadowski, L. Sironi, D. Abarca, X. Guo, F. Ozel, R. Narayan. 2013-01-16. Radio light curves during the passage of cloud G2 near Sgr A*. https://doi.org/10.1093/mnras%2Fstt495

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