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Abstract Auroral particle precipitation is the main source of ionization on the nightside, making it a critical factor in geospace physics. This magnetosphere‐ionosphere linkage directly contributes to, even controls, the nonlinear feedback within this coupled system. One study has dominated our understanding of this connection, presenting a pair of equations relating auroral particle precipitation to ionospheric Pedersen and Hall conductance, the famous Robinson formulas. This Commentary examines the history of the development and usage of the Robinson formulas and the recent studies exploring corrections and expansions to it. The conclusion is that more work needs to be done; the space physics research community should take up the task to develop improvements and enhancements to better quantify the connection of auroral precipitation to ionospheric conductance.
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Incoherent scatter radar observations of 10-100 keV precipitation: review and outlook
ISRs measure backscattered power that is proportional to electron density in the ionosphere (e.g., Dougherty and Farley, 1961; Evans, 1969). To quantify electron density enhancements, a forward model that characterizes the physics of particle precipitation must be developed. Transport models describe the physics of how particle precipitation generates ionization enhancements, while chemistry models describe how ionization modifies the background electron density. In this section, we briefly review particle transport processes and chemistry and provide a brief review of techniques used to estimate particle differential number flux from enhanced electron density measurements.
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- Award ID(s):
- 1732365
- PAR ID:
- 10114212
- Date Published:
- Journal Name:
- The Dynamic Loss of Earth’s Radiation Belts: From Loss in the Magnetosphere to Particle Precipitation in the Atmosphere
- Page Range / eLocation ID:
- 145-189
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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