POLAR Plasma Wave Investigation (PWI)Sweep Frequency Receiver-B (SFR-B) Daily Dynamic Spectrograms

The Polar PWI Sweep Frequency Receiver-B (SFR-B) collected data from March 1996 to September 1997. The SFR-B used the magnetic loop antenna (mounted on a 6m boom and oriented parallel to the Eu antenna). The SFR-B receiver spanned the frequency range from 26 Hz to 808 kHz in 5 bands: 26-200 Hz, 0.2 - 1.6 kHz, 1.7 - 12.6 kHz, 13-100 kHz, 100-808 kHz. Each image is a daily plot of the power spectral density (nT^2 Hz^-1) of received signal (color scale) as a function of operating frequency (in a logarithmic scale on vertical axis) and time (horizontal axis). At the top of each plot is a title indicating the Instrument, Receiver and Antenna used followed by the time span for the spectrogram. Beneath the time labels on the horizontal axis are ephemeris data: position of the spacecraft in radial distance (Earth radii), geomagnetic latitude, magnetic local time, and McIlwain L-shell. Overlaid on each image is a trace of the electron gyrofrequency.