The Solar Lunch for February 2020 will feature the following presentation by
Juan Carlos Martínez Oliveros (University of California at Berkeley, California, USA):
Statistics and polarisation of type III radio bursts observed in the inner heliosphere
The unique location of Parker Solar Probe offers the chance to observe solar radio emission close to the source, measuring signals which are less affected by scattering and refraction than signals observed at 1 AU. We present PSP/FIELDS Radio Frequency Spectrometer (RFS) observations in the inner heliosphere, comparing occurrence rates, amplitudes, and cross spectral properties of solar radio bursts from the first two PSP encounters. During the first encounter, only a few small bursts were observed. During the second encounter, copious Type III radio bursts were observed throughout the entire encounter, including intervals of radio storms where bursts occurred almost continuously. Notably, several strong Type III bursts during the second encounter display signatures of circular polarization from 6-16 MHz, which has been rarely observed at such low frequencies. We discuss the implications for the process of generating radio emission from the electron beams associated with the bursts.