(a) The measured flux density of Stokes I, (b) the linear polarization flux density, and (c) the linear polarization fraction Π_L as a function of frequency. We show the best-fitting model (Equation (B11); dotted lines, shaded regions are 1σ posteriors), which show a constant linear polarization intensity and fraction that decays exponentially to lower frequencies. (d) We show the Stokes U versus Q colorized by observed frequency. The data exhibit a spiral structure indicative of Faraday rotation. The solid line shows the depolarization frequency response derived from Equation (B11), and the shaded region indicates the average 3σ detection threshold for P_L. (e) The polarization angle ﹩\chi =(1/2)\arctan (U/Q)﹩ as a function of λ². The data reveal a steep slope corresponding to a rotation measure (RM) of ∣RM∣ ≈ 6.3 × 10³ rad m⁻², indicative of a highly ordered magnetic field structure along the LOS.