Quantifying the Effects of Electron Shot Noise on a Current Biased Antenna

The Parker Solar Probe (PSP) Fields Experiment (FIELDS) Science Operations Team uses FIELDS Radio Frequency Spectrometer (RFS) data and Quasi-Thermal Noise Spectroscopy (QTN) to determine the temperature and density of electrons in the heliosphere. The FIELDS antennas operate with an applied bias current which causes electron shot-noise in RFS data. The presence of high-amplitude shot-noise makes QTN analysis more difficult by obscuring the plasma line and plasma frequency peak. Despite its applied bias current PSP is one of the first spacecraft to successfully conduct QTN on a current-biased antenna. The effects of the FIELDS antenna bias on the shot-noise spectrum can be quantified by comparing data taken during bias sweep calibration activities. Observing the effects of the applied bias current on the electron shot-noise spectrum can improve determination of electron parameters from QTN and expand contemporary QTN models to account for operating with a bias current.