Solar Orbiter observation near the shock. Panels from top to bottom show the magnetic field components and magnitude, the angle θ_BR between the magnetic field and radial direction, the total magnetic field power spectral density (PSD), and the normalized magnetic helicity σ_m from the Morlet wavelet analysis. The cyan vertical line in each panel represents the current sheet crossing. The horizontal dashed lines in the third panel identify the proton cyclotron frequency in the plasma frame upstream f_cu and downstream f_cd. The dashed dotted lines in the fourth panel shows the equivalent frequency in the spacecraft frame and based on Wind’s plasma measurements.