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Abstract We perform a comprehensive investigation of the statistical distribution of outer belt electron acceleration events over energies from 300 keV to ∼10 MeV regardless of storm activity using 6‐years of observations from Van Allen Probes. We find that the statistical properties of acceleration events are consistent with the characteristic energies of combined local acceleration by chorus waves and inward radial diffusion. While electron acceleration events frequently occur both at <2 MeV atL < 4.0 and at multi‐MeV atL > 4.5, significant acceleration events are confined toL > ∼4.0. By performing superposed epoch analysis of acceleration events during storm and non/weak storm events and comparing their geomagnetic conditions, we reveal the strong correlation (>0.8) between accumulated impacts of substorms as measured by time‐integrated AL (Int(AL)) and the upper flux limit of electron acceleration. While intense storms can provide favorable conditions for efficient acceleration, they are not necessarily required to produce large maximum fluxes.
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Control of Pulse Front Tilt and Curvature for Ultrafast Ponderomotive Electron Acceleration
Weexploreanelectronaccelerationschemewhichusestheponderomotiveforceofatiltedultrafastlaserasthedrivemechanismforacceleration. Theeffectofpulsefrontcurvatureontheaccelerationprocessisalsodiscussed.
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- Award ID(s):
- 1903709
- PAR ID:
- 10416609
- Date Published:
- Journal Name:
- Conference on Lasers and Electrooptics
- ISSN:
- 2160-9020
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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