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Explaining the flat-spectrum radio core Sgr A* with GRMHD simulations of jets

Published online by Cambridge University Press:  24 March 2015

Monika A. Mościbrodzka
Monika A. Mościbrodzka*
Affiliation:
Department of Astrophysics/IMAPP, Radboud University, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands email: m.moscibrodzka@astro.ru.nl
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Abstract

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The supermassive black hole in the center of the Milky Way, Sgr A*, displays a nearly flat radio spectrum which is typical for jets in Active Galactic Nuclei. Indeed, time dependent, magnetized models of radiatively inefficient accretion flows, which are commonly used to explain the millimeter, near-infrared, and X-ray emission of Sgr A* also often produce jet-like outflows. However, the emission from these models so far has failed to reproduce the flat radio spectrum. We show that current GRMHD simulations can naturally reproduce the flat spectrum, when using a two-temperature plasma in the disk and a constant electron temperature plasma in the jet. This assumption is consistent with current state-of-the art simulations, in which the electron temperature evolution is not explicitly modeled. Stronger magnetization and stronger shearing seen in the jet sheath could possibly explain the difference in electron heating between jet and disk. The model images and spectra are consistent with the radio sizes and spectrum of Sgr A*.

Keywords

accretionaccretion disksblack hole physicsMHDradiative transferrelativityGalaxy: center
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 10 , Issue S313: Extragalactic jets from every angle , September 2014 , pp. 374 - 379
Copyright
Copyright © International Astronomical Union 2015 

References

An, T., Goss, W. M., Zhao, J.-H., et al. 2005, ApJL, 634, L49Google Scholar
Bower, G. C., Falcke, H., Wright, M. C., & Backer, D. C. 2005, ApJL, 618, L29Google Scholar
Bower, G. C., Goss, W. M., Falcke, H., Backer, D. C., & Lithwick, Y. 2006, ApJL, 648, L127Google Scholar
Bower, G. C., Markoff, S., Brunthaler, A., et al. 2014, ApJ, 790, 1Google Scholar
Brinkerink, C., Moscibrodzka, M., Fraga-Encinas, R., & Falcke, H., 2014, in preparationGoogle Scholar
Dexter, J., Agol, E., Fragile, P. C., & McKinney, J. C. 2010, ApJ, 717, 1092Google Scholar
Doeleman, S. S., Weintroub, J., Rogers, A. E. E., et al. 2008, Nature, 455, 78Google Scholar
Doeleman, S. S., Fish, V. L., Schenck, D. E., et al. 2012, Science, 338, 355Google Scholar
Falcke, H., Goss, W. M., Matsuo, H., et al. 1998, ApJ, 499, 731Google Scholar
Falcke, H. & Markoff, S. B. 2013, Classical and Quantum Gravity, 30, 244003Google Scholar
Fish, V. L., Doeleman, S. S., Beaudoin, C., et al. 2011, ApJL, 727, L36Google Scholar
Marrone, D. P., Moran, J. M., Zhao, J.-H., & Rao, R. 2006, ApJ, 640, 308Google Scholar
Melia, F. & Falcke, H. 2001, ARAA, 39, 309CrossRefGoogle Scholar
Mościbrodzka, M., Gammie, C. F., Dolence, J. C., Shiokawa, H., & Leung, P. K. 2009, ApJ, 706, 497Google Scholar
Mościbrodzka, M. & Falcke, H. 2013, A&A, 559, L3Google Scholar
Mościbrodzka, M., Falcke, H., Shiokawa, H., & Gammie, C. F. 2014, A&A, 570, AA7Google Scholar
Neilsen, J., Nowak, M. A., Gammie, C., et al. 2013, ApJ, 774, 42CrossRefGoogle Scholar
Noble, S. C., Leung, P. K., Gammie, C. F., & Book, L. G. 2007, Classical and Quantum Gravity, 24, 259Google Scholar
Schödel, R., Morris, M. R., Muzic, K., et al. 2011, A&A, 532, A83Google Scholar