Will nanodust reappear in STEREO/WAVES data?

TL;DR

This paper investigates the detection of nanodust particles in space using wave instruments on spacecraft, focusing on their origin, acceleration, and the conditions that enhance their detectability near the heliospheric current sheet.

Contribution

It analyzes the conditions under which nanodust reappears in STEREO/WAVES data, linking detections to solar magnetic field configurations and particle acceleration mechanisms.

Findings

Nanodust flux is highly variable and linked to solar magnetic field orientation.

Detections are more frequent when the magnetic dipole aligns to focus particles towards the HCS.

Wave instruments can effectively detect vaporized nanodust impacts in space.

Abstract

Nanodust particles produced near the Sun by collisional breakup of larger grains are accelerated in the magnetised solar wind and reach high speeds outwards of 1 AU. Vaporisation and ionisation of fast dust grains impacting a spacecraft produce voltage pulses on wave instruments that enable them to act as dust detectors. Wave instruments on STEREO and on Cassini during its cruise phase detected a highly variable flux of fast nanodust. Both detections took place when the orientation of the solar magnetic dipole produced an interplanetary electric field that focused nanoparticles towards the heliospheric current sheet (HCS) - a geometry that is recurring because of the periodicity of solar activity.