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Abstract We present observations that show structured diffuse aurora (SDA) correlated with electron precipitation directly from the outer boundary of the outer radiation belt. The SDA maps to the nightside transition region (∼9–12RE) in the magnetic‐equatorial plane during a substorm growth phase. The energy flux of 100‐ to 300‐keV electrons lost from the outer boundary of the radiation belt is ∼0.4 mW/m2, which is comparable to electron dropouts >100 keV during magnetic storms. The latitudinal dispersion of energetic electrons observed in the ionosphere with energetic electrons more equatorward suggests nonadiabatic scattering from a thinning current sheet. The GLobal airglOW (GLOW) model shows significant optical contributions (up to 46%) from electrons >30 keV within the SDA. Ground‐ and space‐based measurements are consistent with the conclusion that the SDA marks the outer radiation belt boundary during substorm growth phase.
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Interior Regularity for Two-Dimensional Stationary Q-Valued Maps
Abstract We prove that 2-dimensionalQ-valued maps that are stationary with respect to outer and inner variations of the Dirichlet energy are Hölder continuous and that the dimension of their singular set is at most one. In the course of the proof we establish a strong concentration-compactness theorem for equicontinuous maps that are stationary with respect to outer variations only, and which holds in every dimensions.
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- Award ID(s):
- 2044954
- PAR ID:
- 10525645
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Archive for Rational Mechanics and Analysis
- Volume:
- 248
- Issue:
- 4
- ISSN:
- 0003-9527
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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