Journal article
Statistical properties of plasmaspheric hiss derived from Van Allen Probes data and their effects on radiation belt electron dynamics
Journal of geophysical research. Space physics, Vol.120(5), pp.3393-3405
05/2015
DOI: 10.1002/2015JA021048
Abstract
Plasmaspheric hiss is known to play an important role in controlling the overall structure and dynamics of radiation belt electrons inside the plasmasphere. Using newly available Van Allen Probes wave data, which provide excellent coverage in the entire inner magnetosphere, we evaluate the global distribution of the hiss wave frequency spectrum and wave intensity for different levels of substorm activity. Our statistical results show that observed hiss peak frequencies are generally lower than the commonly adopted value (~550 Hz), which was in frequent use, and that the hiss wave power frequently extends below 100 Hz, particularly at larger L shells (> ~3) on the dayside during enhanced levels of substorm activity. We also compare electron pitch angle scattering rates caused by hiss using the new statistical frequency spectrum and the previously adopted Gaussian spectrum and find that the differences are up to a factor of ~5 and are dependent on energy and L shell. Moreover, the new statistical hiss wave frequency spectrum including wave power below 100 Hz leads to increased pitch angle scattering rates by a factor of ~1.5 for electrons above ~100 keV at L~5, although their effect is negligible at L ≤ 3. Consequently, we suggest that the new realistic hiss wave frequency spectrum should be incorporated into future modeling of radiation belt electron dynamics.
Key Points
Hiss wave power is activity dependent and frequently extends below 100 Hz
Hiss peak frequency is dependent on L and lower than the previous value 550 Hz
Difference in hiss diffusion rate is up to 5, and realistic spectra should be used
Details
- Title: Subtitle
- Statistical properties of plasmaspheric hiss derived from Van Allen Probes data and their effects on radiation belt electron dynamics
- Creators
- W Li - University of California, Los AngelesC. A Kletzing - University of IowaQ Ma - University of California, Los AngelesW. S Kurth - University of IowaR. M Thorne - University of California, Los AngelesG. B Hospodarsky - University of IowaJ Bortnik - University of California, Los AngelesY Nishimura - University of California, Los Angeles
- Resource Type
- Journal article
- Publication Details
- Journal of geophysical research. Space physics, Vol.120(5), pp.3393-3405
- DOI
- 10.1002/2015JA021048
- ISSN
- 2169-9380
- eISSN
- 2169-9402
- Number of pages
- 13
- Grant note
- NSF (AGS 1405054) ECT (13–041) EMFISIS (1001057397:01) JHU/APL (967399; 921647) NASA (NAS5‐01072; NNX11AD75G; NNX11AR64G; NNX13AI61G; NNX15AI96G; NNX14AI18G; NNX15AF61G)
- Language
- English
- Date published
- 05/2015
- Academic Unit
- Physics and Astronomy
- Record Identifier
- 9984200028102771
Metrics
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