PSP Magnetic field Wavelet Energy and Polarization Spectra Plots

The Dataset contains plots of (a) the magnetic field spectra as a function of frequency, and (b) the spacecraft-frame circular polarization as a function of frequency and time, for continuous 15-minute intervals from Parker Solar Probe (PSP) FIELDS Fluxgate magnetometer (MAG) observations for Encounters 3-24. The observed PSDs are distinguished into ion-scale circularly polarized waves and turbulence via the following approach, as described in Niranjana et al. 2023, 24 (NKM23, 24). The magnetic field time series of all encounters is split into continuous 15-minute intervals and the following routine is applied on each interval: (a) the reaction-wheel noise is identified and removed (Appendix B.1 of NKM23), (b) the time series is downsampled to a frequency at which magnetic energy spectra hits the MAG noise floor, (c) the spectrum of circular polarization of magnetic field fluctuations in the spacecraft frame is evaluated as a function of frequency and time using Mortlet wavelet transforms, distinguishing observed PSD into ion-scale waves (with high values of circular polarization) and turbulence (with low values of circular polarization; Appendices B.3. and B.4. of NKM23), and (d) a time smoothing routine is further applied on the polarization spectra to retain (exclude) persistent (random) high values of circular polarization, distinguishing the left-handed (LH) and right-handed (RH) ion-scale wave PSDs (Apendix A of NKM24). Each plot in this dataset has the following four subplots, (1) Top left- The subplot shows, as a function of frequency, the total Fourier PSD before and after reaction wheel noise removal (blue and orange, respectively) and the total wavelet PSD after noise removal (green). The green curve is further distinguished into ion-scale waves PSD (red) and turbulent PSD (not shown). (2) Bottom left- The subplot illustrates, as a function of frequency, the total wavelet PSD after noise removal (blue, same as green curve in top left subplot) and ion-scale waves PSD (black, same as red curve in top left subplot). The black curve is further discerned into the LH (red) and RH (blue) ion-scale wave PSD. (3) Top right- The spectrum of circular polarization, sigma, in the spacecraft frame as a function of time and frequency. (4) Bottom right- Time-smoothed spectrum of sigma. NOTE: (a) The sum of LH and RH ion-scale wave PSDs (red and blue curves, respectively, in bottom left subplot) doesn't necessarily add up to the ion-scale wave PSD (black curve in bottom left subplot), particularly for weak waves. This is because random high values of sigma in the frequency-time space that are included in the black curve are excluded in the red and blue curves due to applying time smoothing in the latter. Furthermore, a small fraction of genuine ion-scale wave energy is lost by time-smoothing.