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Abstract The rapidly expanding fleet of low‐altitude CubeSats equipped with energetic particle detectors brings new opportunities for monitoring the dynamics of the radiation belt and near‐Earth plasma sheet. Despite their small sizes, CubeSats can carry state‐of‐the‐art instruments that provide electron flux measurements with finer energy resolution and broader energy coverage, compared to conventional missions such as POES satellites. The recently launched CIRBE CubeSat measures 250–6,000 keV electrons with extremely high energy resolution, however, CIRBE typically only measures locally‐trapped electrons and cannot directly measure the precipitating electrons. This work aims to develop a technique for identifying indications of nightside precipitation using the locally‐trapped electron measurements by the CIRBE CubeSat. This study focuses on two main types of drivers for nightside precipitation: electron scattering by the curvature of magnetic field lines in the magnetotail current sheet and electron scattering by resonance with electromagnetic ion cyclotron (EMIC) waves. Using energy and pitch‐angle resolved electron fluxes from the low‐altitude ELFIN CubeSat, we reveal the features that distinguish between these two precipitation mechanisms based solely on locally‐trapped flux measurements. Then we present measurements from four CIRBE orbits and demonstrate the applicability of the proposed technique to the investigation of nightside precipitation using CIRBE observations, enabling separation between precipitation induced by curvature scattering and EMIC waves in nearby regions. Our study underscores the feasibility of employing high‐energy‐resolution CIRBE measurements for detecting nightside precipitation of relativistic electrons. Additionally, we briefly discuss outstanding scientific questions about these precipitation patterns that could be addressed with CIRBE measurements.
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Power-Efficient Software Architecture for a CubeSat System
A 2U CubeSat, (20cm by 10 cm by 10 cm) is being developed to make impedance measurements of plasma in the ionosphere at 400 km altitude. Because the new instrument is able to make measurements rapidly, and because of the severe power and size constraints of the satellite, special care is needed in storing the measurement data and transmitting it to Earth. For both the measurements and for general housekeeping functions, the software of the CubeSat must be able to respond rapidly to events and operate in a manner that is not only flexible and extensible but also power efficient. This work outlines the process by which the software was designed to satisfy the constraints of the mission.
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- Award ID(s):
- 1655280
- PAR ID:
- 10221589
- Date Published:
- Journal Name:
- IEEE SoutheastCon 2020, Raleigh, NC.
- Page Range / eLocation ID:
- 1 to 6
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/SoutheastCon44009.2020.9249713
