Dynamical spectra of the compressional (C), left- (L), and right-hand (R) polarised field components during the entire flyby. The white vertical lines connected by horizontal lines are the regions where θ_c ≈ θ_c, SW. The bottom panel shows the ratio L/R. The thin white lines are the proton cyclotron frequency f_cp. The thick red and white line in the bottom panel are ten and six times the proton cyclotron frequency, respectively (see text).