Interplanetary scintillation (IPS) analyses during LOFAR campaign mode periods that include the first three Parker Solar Probe close passes of the Sun

Abstract

The University of California, San Diego (UCSD) time-dependent three-dimensional (3-D) reconstruction technique provides volumetric maps of density, velocity, and solar surface extrapolated magnetic fields by iteratively fitting our kinematic 3-D model to interplanetary scintillation (IPS) observations. While we currently use data from the Institute for Space-Earth Environmental Research (ISEE), Japan, we have also integrated this system adding data from Worldwide IPS Stations (WIPSS) network groups to increase both spatial and temporal coverage when these data are available. Some of these stations, especially the LOw Frequency ARray (LOFAR), centered in the Netherlands, currently operate in “campaign” mode only during periods of interest when the Parker Solar Probe (PSP) makes close passes to the Sun. The UCSD 3-D iterative reconstruction technique is unique in its ability to yield a low-resolution seamless extension of density and velocity parameters measured in situ, going outward into the surrounding interplanetary medium at the resolution of the volumetric data. We here present analyses using archival data sets from both ISEE, LOFAR, and BSA3 (Pushchino, Russia), mostly during PSP close passes of the Sun. These analyses provide the location of all inner planets from Mercury to Mars, and the spacecraft PSP, BepiColombo, and Solar Orbiter in the 3-D reconstructed volumes and can show the heliospheric structures that reach them as in-situ predictions of the structures present and forecasts of these parameters in near real time compared with near-Earth data sets.