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arXiv · 1309.0103

The magnetosphere of the close accreting PMS binary V4046 Sgr

S. G. Gregory·V. R. Holzwarth·J. -F. Donati·G. A. J. Hussain·T. Montmerle·E. Alecian·S. H. P. Alencar·C. Argiroffi·M. Audard·J. Bouvier·F. Damiani·M. Güdel·D. P. Huenemoerder·J. H. Kastner·A. Maggio·G. G. Sacco·G. A. Wade
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Abstract

V4046 Sagittarii AB is a close short-period classical T Tauri binary. It is a circularised and synchronised system accreting from a circumbinary disk. In 2009 it was observed as part of a coordinated program involving near-simultaneous spectropolarimetric observations with ESPaDOnS at the Canada-France-Hawai'i Telescope and high-resolution X-ray observations with XMM-Newton. Magnetic maps of each star were derived from Zeeman-Doppler imaging. After briefly highlighting the most significant observational findings, we present a preliminary 3D model of the binary magnetosphere constructed from the magnetic maps using a newly developed binary magnetic field extrapolation code. The large-scale fields (the dipole components) of both stars are highly tilted with respect to their rotation axes, and their magnetic fields are linked.

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S. G. Gregory, V. R. Holzwarth, J. -F. Donati, G. A. J. Hussain, T. Montmerle, E. Alecian, S. H. P. Alencar, C. Argiroffi, M. Audard, J. Bouvier, F. Damiani, M. Güdel, D. P. Huenemoerder, J. H. Kastner, A. Maggio, G. G. Sacco, G. A. Wade. 2013-08-31. The magnetosphere of the close accreting PMS binary V4046 Sgr. https://doi.org/10.1051/epjconf%2F20136408009

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