Statistical Properties of Plasmaspheric Hiss from Van Allen Probes

0477775 - ÚFA 2018 BE eng A - Abstrakt
Hartley, D. P. - Kletzing, C. A. - Bounds, S. R. - Kurth, W. S. - Hospodarsky, G. B. - Santolík, Ondřej - Horne, R. B.
Statistical Properties of Plasmaspheric Hiss from Van Allen Probes.
Papers from URSI: XXXIInd General Assembly and Scientific Symposium (URSI GASS). Ghent: URSI, 2017. H3-2.
[URSI General Assembly and Scientific Symposium (URSI GASS) 2017 /32./. 19.08.2017-26.08.2017, Montreal]
Institucionální podpora: RVO:68378289
Klíčová slova: whistler mode wave * plasmaspheric hiss * Van Allen Probe
Kód oboru RIV: BL - Fyzika plazmatu a výboje v plynech

In this study, plasmaspheric hiss wave properties are investigated using Van Allen Probes observations of both electric and magnetic field wave power spectra over a range of different L shells within the plasmasphere. Previous studies have reported both an approximately field aligned, and a highly oblique, population of plasmaspheric hiss waves occurring only at larger L shells within the plasmasphere [7,8] with predominantly field aligned hiss waves observed at smaller L shells [9]. In contrast, this study reports that the wave normal direction is predominantly field aligned at larger L shells, with a bimodal distribution becoming more apparent at lower L shells. Investigation of the population of oblique plasmaspheric hiss waves reveals that it is most prevalent at L < 3, frequencies greater than 700 Hz, and typically confined between 1900 an 0900 MLT. This MLT structure is similar to that reported for oblique chorus waves outside of the plasmasphere at larger L shell [10]. Ray tracing results, from the HOTRAY model, are consistent with oblique chorus waves as the source of the observed oblique plasmaspheric hiss waves at low L shells. Reasoning is also presented for the absence of these oblique hiss waves in observations at larger L shells within the plasmasphere.

Trvalý link: http://hdl.handle.net/11104/0274022