CAREER: Quantifying Radiation Belt Precipitation and Atmospheric Impacts through D-region Ionosphere Imaging

High energy particles from the Sun constantly bombard the Earth. Many are trapped by the Earth’s magnetic field in a region called radiation belt, which extends from an altitude of about 640 to 58,000 km. These trapped high energy particles can come down to the upper atmosphere at polar region (a process called particle precipitation), interacting with atmospheric molecules to create the colorful aurora.

Some very high energy particles can come further down, depositing energy into the atmosphere and altering the chemistry, and affecting global energy balance and circulation. The effects of these high energy particles are not well understood because of lack of measurements of the particles lost from the radiation belt into the atmosphere.

This CAREER project outlines an integrated research and education initiative to quantify particle losses from the radiation belts and their effects in the upper atmosphere, using an affordable, large-scale imaging technique. Radiation belt precipitation forms a critical link between the magnetosphere, ionosphere, and atmosphere. The Principal Investigator (PI)'s research goal is to quantify the flux, spectra, spatial and temporal scales of energetic particle precipitation (EPP) events, their chemical effects in the upper atmosphere, and their effects on radiation belt populations.

In pursuit of these research goals, the PI will: i) establish a low-cost, autonomous very-low-frequency observation network across Canada to observe variations due to EPP in the mid- to high-latitude D-region ionosphere; ii) refine and improve our understanding of EPP signatures and processes and their relationship to radiation belt losses using an ensemble Kalman Filter-based inversion technique; and iii) validate results using operational spacecraft data.

The PI's education goal is to build a robust undergraduate and graduate education and training program in space physics and engineering at CU Boulder by: i) advising PhD and undergraduate students while maintaining the PI's track record for recruiting and supporting female and underrepresented students; ii) incorporating research outcomes into the graduate space physics curriculum through a new upper-level graduate course; iii) providing research experience opportunities to high school students; and iv) promoting broader understanding of space physics in the non-technical community through a new campus-wide undergraduate course on the space environment and its effects and a new textbook covering this course material.

Quantifying precipitating fluxes will also lead to improved Space Weather nowcasting and forecasting and has implications for spacecraft design and operations in the radiation belts; orbital dynamics and drag in Low Earth Orbit; and radiation safety for high-altitude aircraft.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.