Advanced Instrumentation and Flux Mapping Techniques for the Study of the Space Environment.

[摘要] The study of particle populations such as the solar wind, pickup ions, and energeticparticles, provides clues to the physical processes that govern the space environment.Some of these particle populations are not well understood due to their low densitiesand the low-sensitivity of instruments that are not specifically designed to search forthem. With a new technique for mapping the solar magnetic field on which energeticparticles travel, as well as improved instrumentation with the sensitivity necessaryto measure low-density particle populations, the research outlined here will providea new, powerful set of tools for studying the space environment. The Diffusive EquilibriumMapping technique takes any footpoint of open magnetic flux on the solarsurface and calculates where it reaches in the heliosphere, assuming pressure equilibrium.This method can model magnetic flux configurations that include open fluxdistributed outside of coronal holes, which may contribute to the source of streamersolar wind. Certain limitations on plasma mass spectrometers are investigated andovercome in the IonSpec design, which is capable of measuring an energy-per-chargepassband of (E/q)max = 3(E/q)min in a single voltage step. IonSpec has a largerintegration time, geometric duty cycle, and energy-geometrical factor than similarinstruments and is capable of measuring the elemental abundances and ionic chargecomposition of all major solar wind and pickup ion species. In addition, a novel modificationto cylindrically symmetric linear-electric-field time-of-flight analyzers allowsfor the focusing of secondary electrons emitted by the impact of isochronous ions. Byidentifying secondary electron peaks using their impact position, a single anode canbe used to record both straight-through and isochronous flight times without a lossin the high-resolution isochronous measurement from a low signal-to-noise ratio. Thenew mapping technique and novel instrument designs will enable studies of the spaceenvironment that were previously not possible.

[发布机构] University of Michigan

[效力级别] Instrumentation

[关键词] Solar Wind;Instrumentation;Space Plasma;Open Flux;Atmospheric;Oceanic and Space Sciences;Engineering;Science;Atmospheric and Space Sciences