Compositional Pickup Ion Measurements Out of the Dayside Magnetopause
Presentation Type
Talk
Presenter Format
In Person Meeting Talk
Topic
Dayside Science
Start Date
10-5-2022 1:00 PM
Abstract
The composition of ion fluxes outside the Earth’s magnetosphere varies with its location relative to the Sun. Other factors influencing these fluxes are the intensity of the Sun’s radiation environment, as dictated by the Solar Cycle’s activity level. Major Solar Wind (SW) ions, mostly hydrogen is an indicator of this activity level and, in part, a portion of the radiation environment. However, other ion populations are lower in flux, more varied in species, and assume single-charge states, making them easily distinguishable from SW ions.
While generated from different neutral sources, their production and associated motion with the interplanetary magnetic field (IMF) lead to their generalized moniker, pickup ions (PUIs). At 1 AU, charge exchange and UV photons ionize neutral atoms and produce PUIs. The atoms available for ion production vary with the Earth’s location. For instance, certain interstellar species, mainly helium, peak in availability annually in Early December. Other populations, such as hydrogen atoms from the Earth’s exosphere, are consistently available throughout the Earth’s orbital period. Composition measurements with the Hot Plasma Composition Analyzers (HPCAs) allow spatial and temporal measurements of these ions.
Compositional Pickup Ion Measurements Out of the Dayside Magnetopause
The composition of ion fluxes outside the Earth’s magnetosphere varies with its location relative to the Sun. Other factors influencing these fluxes are the intensity of the Sun’s radiation environment, as dictated by the Solar Cycle’s activity level. Major Solar Wind (SW) ions, mostly hydrogen is an indicator of this activity level and, in part, a portion of the radiation environment. However, other ion populations are lower in flux, more varied in species, and assume single-charge states, making them easily distinguishable from SW ions.
While generated from different neutral sources, their production and associated motion with the interplanetary magnetic field (IMF) lead to their generalized moniker, pickup ions (PUIs). At 1 AU, charge exchange and UV photons ionize neutral atoms and produce PUIs. The atoms available for ion production vary with the Earth’s location. For instance, certain interstellar species, mainly helium, peak in availability annually in Early December. Other populations, such as hydrogen atoms from the Earth’s exosphere, are consistently available throughout the Earth’s orbital period. Composition measurements with the Hot Plasma Composition Analyzers (HPCAs) allow spatial and temporal measurements of these ions.
