In situ observations of large-amplitude Alfvén waves heating and accelerating the solar wind.

After leaving the Sun's corona, the solar wind continues to accelerate and cools, but more slowly than expected for a freely expanding adiabatic gas. Alfvén waves are perturbations of the interplanetary magnetic field that transport energy. We use in situ measurements from the Parker Solar Probe and Solar Orbiter spacecraft to investigate a stream of solar wind as it traverses the inner heliosphere.

A double-cusp type electrostatic analyzer for high-cadence solar-wind suprathermal ion observations.

This paper describes a novel electrostatic analyzer concept to measure suprathermal ions, a Double-Cusp Analyzer for SupraThermals (DCAST) that employs a double-shell cusp structure. Due to the necessity of measuring higher energy levels to cover the suprathermal range, existing ion instruments require greater size and mass. Moreover, observations of potentially low-flux suprathermal ions require a long integration time to fully characterize key ion properties in the plasmas (e.

Avalanche photodiode based time-of-flight mass spectrometry.

This study reports on the performance of Avalanche Photodiodes (APDs) as a timing detector for ion Time-of-Flight (TOF) mass spectroscopy. We found that the fast signal carrier speed in a reach-through type APD enables an extremely short timescale response with a mass or energy independent <2 ns rise time for <200 keV ions (1-40 AMU) under proper bias voltage operations. When combined with a microchannel plate to detect start electron signals from an ultra-thin carbon foil, the APD comprises a novel TOF system that successfully operates with a <0.