Abstract:
Observations of the properties of elements heavier than helium in the heliosphere, including their charge state and elemental composition, can reveal key information about their origin. Space borne ion mass spectrometers measure these heavy ions and have flown on a variety of trajectories through the solar system. Data from these spectrometers have provided critical information on how plasma originates in the solar corona and is accelerated out into the heliosphere. For example, highly ionized material observed inside interplanetary coronal mass ejections (ICMEs) originates from explosively heated plasma low in the solar corona during eruptions. Additional sources of plasma outside the Sun also contribute material to the solar wind and can be studied to understand the Sun's interaction with solar system bodies. For example, interstellar material, neutral material and dust in the solar system, and material stripped from comets and planets can be picked up by the solar wind and retain unique fingerprints about their origin and physical processes in the heliosphere. My talk will review the state of the field of heavy ion composition in the heliosphere, highlight U of M developed heavy ion mass spectrometers, and discuss future directions for research.