“Trunk-like” heavy ion structures observed by the Van Allen Probes [electronic resource].
- Washington, D.C. : United States. Dept. of Energy, 2015.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy
- Physical Description:
- pages 8,738-8,748 : digital, PDF file
- Additional Creators:
- Los Alamos National Laboratory, United States. Department of Energy, and United States. Department of Energy. Office of Scientific and Technical Information
- Restrictions on Access:
- Free-to-read Unrestricted online access
- Dynamic ion spectral features in the inner magnetosphere are the observational signatures of ion acceleration, transport, and loss in the global magnetosphere. Here, we report “trunk-like” ion structures observed by the Van Allen Probes on 2 November 2012. This new type of ion structure looks like an elephant's trunk on an energy-time spectrogram, with the energy of the peak flux decreasing Earthward. The trunks are present in He+ and O+ ions but not in H+. During the event, ion energies in the He+ trunk, located at L=3.6–2.6, magnetic local time (MLT)=9.1–10.5, and magnetic latitude (MLAT) =-2.4–0.09°, vary monotonically from 3.5 to 0.04 keV. Values at the two end points of the O+ trunk are energy=4.5–0.7keV, L=3.6–2.5, MLT=9.1–10.7, and MLAT=-2.4–0.4°. Our results from backward ion drift path tracings indicate that the trunks are likely due to (1) a gap in the nightside ion source or (2) greatly enhanced impulsive electric fields associated with elevated geomagnetic activity. Different ion loss lifetimes cause the trunks to differ among ion species.
- Report Numbers:
- E 1.99:la-ur--15-28232
- Published through SciTech Connect.
Journal of Geophysical Research. Space Physics 120 10 ISSN 2169-9380 AM
J. -C. Zhang; L. M. Kistler; H. E. Spence; R. A. Wolf; G. Reeves; R. Skoug; H. Funsten; B. A. Larsen; J. T. Niehof; E. A. MacDonald; R. Friedel; C. P. Ferradas; H. Luo.
- Funding Information:
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