Small Electron Events Observed by Parker Solar Probe/IS⊙IS during Encounter 2

Author
Keywords
Abstract
<p>The current understanding of the characteristics of\&nbsp;solar\&nbsp;and inner heliospheric electron events is inferred almost entirely from observations made by spacecraft located at 1 astronomical unit (au). Previous observations within 1 au of the Sun, by the Helios spacecraft at similar to 0.3-1 au, indicate the presence of electron events that are not detected at 1 au or may have merged during transport from the Sun.\&nbsp;Parker\&nbsp;Solar\&nbsp;Probe\textquoterights close proximity to the Sun at perihelion provides an opportunity to make the closest measurements yet of energetic electron events. We present an overview of measurements of electrons with energies between similar to 17 keV and similar to 1 MeV made by the\&nbsp;Parker\&nbsp;Solar\&nbsp;Probe\&nbsp;Integrated Science Investigation of the Sun (ISIS) instrument suite during Encounter 2 (2019 March 31-April 10 with perihelion of similar to 0.17 au), including several small electron events. We examine these events in the context of the electromagnetic and\&nbsp;solar\&nbsp;wind environment measured by the FIELDS and SWEAP instruments on\&nbsp;Parker\&nbsp;Solar\&nbsp;Probe. We find most of these electron enhancements to be associated with type III radio emissions that reach the local plasma frequency and one enhancement that appears to be primarily associated with abrupt changes in the local magnetic field. Together, these associations suggest that these are indeed the first measurements of energetic electron events within 0.2 au.</p>
Year of Publication
2020
Journal
The Astrophysical Journal
Volume
902
Number
Number of Pages
20
Date Published
10/2020
URL
https://iopscience.iop.org/article/10.3847/1538-4357/abb2a4https://iopscience.iop.org/article/10.3847/1538-4357/abb2a4/pdf
DOI
10.3847/1538-4357/abb2a4