The magnetosphere of the close accreting PMS binary V4046 Sgr

TL;DR

This paper investigates the magnetic properties of the close PMS binary V4046 Sgr, combining spectropolarimetric and X-ray observations to model its magnetosphere and reveal linked, tilted magnetic fields.

Contribution

It presents the first 3D model of the binary magnetosphere based on Zeeman-Doppler imaging and a new magnetic field extrapolation code.

Findings

Large-scale magnetic fields are highly tilted and linked between the stars.

Magnetic maps reveal significant magnetic activity and field topology.

The model provides insights into magnetic interactions in close PMS binaries.

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.