Home » Califf et al. 2017

The role of the convection electric field in filling the slot region between the inner and outer radiation belts

Califf S., X. Li, H. Zhao, A. Kellerman, T. E. Sarris, A. Jaynes, D. M. Malaspina, (2017), The role of the convection electric field in filling the slot region between the inner and outer radiation belts, J. of Geophys. Res. [Space Physics], 122, 2051-2068, doi:10.1002/2016JA023657

Abstract

Abstract The Van Allen Probes have reported frequent flux enhancements of 100s keV electrons in the slot region, with lower energy electrons exhibiting more dynamic behavior at lower L shells. Also, in situ electric field measurements from the Combined Release and Radiation Effects Satellite, Time History of Events and Macroscale Interactions during Substorms (THEMIS), and the Van Allen Probes have provided evidence for large-scale electric fields at low L shells during active times. We study an event on 19 February 2014 where hundreds of keV electron fluxes were enhanced by orders of magnitude in the slot region and electric fields of 1–2 mV/m were observed below L = 3. Using a 2-D guiding center particle tracer and a simple large-scale convection electric field model, we demonstrate that the measured electric fields can account for energization of electrons up to at least 500 keV in the slot region through inward radial transport.

Authors (sorted by name)

Jaynes Kellerman Li Malaspina Zhao

Journal / Conference

Journal Of Geophysical Research (Space Physics)

Acknowledgments

The work at the University of Colorado was mainly supported by funding through NASA Earth and Space Sciences Fellowship (NESSF) award NNX15AT57H and also partially supported by NASA grant NNX15AF56G. The authors thank the Van Allen Probes EFW, MagEIS, HOPE, and EMFISIS teams for providing data for this study. The Van Allen Probes MagEIS and HOPE data are publicly available at http://www.rbsp‐ect.lanl.gov, the EFW data can be found at http://www.space.umn.edu/rbspefw‐data, and the EMFISIS data are at http://emfisis.physics.uiowa.edu/data/index. Spin fit electric and magnetic field data for THEMIS can be found at http://themis.ssl.berkeley.edu/data/themis/tha/l2/fit, and OMNI data are located at http://cdaweb.gsfc.nasa.gov.

Grants

NNX15AF56G NNX15AT57H

Bibtex

@article{doi:10.1002/2016JA023657,
author = {Califf, S. and Li, X. and Zhao, H. and Kellerman, A. and Sarris, T. E. and Jaynes, A. and Malaspina, D. M.},
title = {The role of the convection electric field in filling the slot region between the inner and outer radiation belts},
year = {2017},
journal = {Journal of Geophysical Research: Space Physics},
volume = {122},
number = {2},
pages = {2051-2068},
keywords = {convection, electric field, slot region, electrons},
doi = {10.1002/2016JA023657},
url = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2016JA023657},
eprint = {https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2016JA023657},
abstract = {Abstract The Van Allen Probes have reported frequent flux enhancements of 100s keV electrons in the slot region, with lower energy electrons exhibiting more dynamic behavior at lower L shells. Also, in situ electric field measurements from the Combined Release and Radiation Effects Satellite, Time History of Events and Macroscale Interactions during Substorms (THEMIS), and the Van Allen Probes have provided evidence for large-scale electric fields at low L shells during active times. We study an event on 19 February 2014 where hundreds of keV electron fluxes were enhanced by orders of magnitude in the slot region and electric fields of 1–2 mV/m were observed below L = 3. Using a 2-D guiding center particle tracer and a simple large-scale convection electric field model, we demonstrate that the measured electric fields can account for energization of electrons up to at least 500 keV in the slot region through inward radial transport.}
}