A Constraint on the Organization of the Galactic Center Magnetic Field Using Faraday Rotation

Understand

We present new 6 and 20 cm Very Large Array (VLA) observations of polarized continuum emission of roughly 0.5 square degrees of the Galactic center (GC) region.

• The 6 cm observations detect diffuse linearly-polarized emission throughout the region with a brightness of roughly 1 mJy per 15"x10" beam.
• The Faraday rotation measure (RM) toward this polarized emission has structure on degree size scales and ranges from roughly +330 rad/m2 east of the dynamical center (Sgr A) to -880 rad/m2 west of the dynamical center.
• This RM structure is also seen toward several nonthermal radio filaments, which implies that they have a similar magnetic field orientation and constrains models for their origin.