Zoomed-in view of central region of CO J = 2 − 1 emission previously shown in Fig. 2. The greyscale indicates the Stokes I emission and the blue line segments indicate the linearly polarisation direction. The red dashed contours represent the (negative) Stokes V emission at −8, −6, and −4σ, where σ = 0.4 mJy beam⁻¹. The outflow direction is indicated by the dashed line. The blue box indicates the region of the 1612 MHz OH masers for which a linear polarisation map is presented in B03 (their Fig. 7). The majority of the OH masers are located within ∼0.4″ of the centre of the map. The channel velocity in km s⁻¹ is given the top right corner of each panel.