  On April 5, 2019, while the Parker Solar Probe was at its 35 solar radius
perihelion, the data set collected at 293 samples/sec contained more than
10,000 examples of spiky electric-field-like structures having durations less
than 200 milliseconds and amplitudes greater than 10 mV/m. The vast majority of
these events was caused by plasma turbulence. Defining dust events as those
having similar, narrowly peaked, positive, single-ended signatures, resulted in
finding 135 clear dust events, which, after correcting for the low detection
efficiently, resulted in an estimate consistent with the 1000 dust events
expected from other techniques. Defining time domain structures (TDS) as those
having opposite polarity signals in the opposite antennas resulted in finding
238 clear TDS events which, after correcting for the detection efficiency,
resulted in an estimated 500-1000 TDS events on this day. The TDS electric
fields were bipolar, as expected for electron holes. Several events were found
at times when the magnetic field was in the plane of the two measured
components of the electric field such that the component of the electric field
parallel to the magnetic field was measured. One example of significant
parallel electric fields shows the negative potential that classified them as
electron holes. Because the TDS observation rate was not uniform with time, it
is likely that there were local regions below the spacecraft with field-aligned
currents that generated the TDS.
