Identification of PCWs at Mars during the passage of an SIR (No. 23 SIR in Table A.1) and its upstream and downstream regions. From top to bottom: (a) MAVEN spacecraft altitude, (b) PSD of the transverse magnetic field component (B_TRA), (c) PSD of the compressional magnetic field component (B_COMP), (d) B_TRA to total PSD ratio, (e) wave propagation angle (θ_kB), (f) ellipticity (−1/+1 = LH/RH circular polarization), (g) wave amplitude (δB), (h) PCW diagnostics (“Yes” or “No” signifies a presence or absence of PCWs, respectively), and (i) IMF cone angle (α_VB). Two vertical dashed blue lines delimit the SIR. The white-shaded regions in panels (b)–(f) and the light green-shaded region in panel (h) mark the frequency range from 0.8ƒ_H+ to 1.2ƒ_H+.