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Morley SK, Friedel RHW, Spanswick EL, Reeves GD, Steinberg JT, Koller J, Cayton T, Noveroske E. Dropouts of the outer electron radiation belt in response to solar wind stream interfaces: global positioning system observations. Proc Math Phys Eng Sci 2010. [DOI: 10.1098/rspa.2010.0078] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We present a statistical study of relativistic electron counts in the electron radiation belt across a range of drift shells (L*>4) combining data from nine combined X-ray dosimeters (CXD) on the global positioning system (GPS) constellation. The response of the electron counts as functions of time, energy and drift shell are examined statistically for 67 solar wind stream interfaces (SIs); two-dimensional superposed epoch analysis is performed with the CXD data. For these epochs we study the radiation belt dropouts and concurrent variations in key geophysical parameters.
At higher L* we observe a tendency for a gradual drop in the electron counts over the day preceding the SI, consistent with outward diffusion and magnetopause shadowing. At all L*, dropouts occur with a median time scale of ≃7 h and median counts fall by 0.4–1.8 orders of magnitude. The central tendencies of radiation belt dropout and recovery depend on both L* and energy. For ≃70 per cent of epochs Sym-H more than −30 nT, yet only three of 67 SIs did not have an associated dropout in the electron data. Statistical maps of electron precipitation suggest that chorus-driven relativistic electron microbursts might be major contributors to radiation belt losses under high-speed stream driving.
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Affiliation(s)
- Steven K. Morley
- Space Science and Applications, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Reiner H. W. Friedel
- Space Science and Applications, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Emma L. Spanswick
- Space Science and Applications, Los Alamos National Laboratory, Los Alamos, NM, USA
- Department of Physics and Astronomy, University of Calgary, Calgary, Alberta, Canada
| | - Geoffrey D. Reeves
- Space Science and Applications, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - John T. Steinberg
- Space Science and Applications, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Josef Koller
- Space Science and Applications, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Thomas Cayton
- Space Science and Applications, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Evan Noveroske
- Space Data Systems, Los Alamos National Laboratory, Los Alamos, NM, USA
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Tu W, Li X, Chen Y, Reeves GD, Temerin M. Storm-dependent radiation belt electron dynamics. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2008ja013480] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Weichao Tu
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - Xinlin Li
- Laboratory for Atmospheric and Space Physics; University of Colorado; Boulder Colorado USA
| | - Yue Chen
- Los Alamos National Laboratory; Los Alamos New Mexico USA
| | - G. D. Reeves
- Los Alamos National Laboratory; Los Alamos New Mexico USA
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Jordanova VK, Albert J, Miyoshi Y. Relativistic electron precipitation by EMIC waves from self-consistent global simulations. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2008ja013239] [Citation(s) in RCA: 202] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - J. Albert
- Air Force Research Laboratory; Hanscom AFB Massachusetts USA
| | - Y. Miyoshi
- Solar-Terrestrial Environment Laboratory; Nagoya University; Nagoya Japan
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Li W, Shprits YY, Thorne RM. Dynamic evolution of energetic outer zone electrons due to wave-particle interactions during storms. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2007ja012368] [Citation(s) in RCA: 285] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- W. Li
- Department of Atmospheric and Oceanic Sciences; University of California Los Angeles; Los Angeles California USA
| | - Y. Y. Shprits
- Department of Atmospheric and Oceanic Sciences; University of California Los Angeles; Los Angeles California USA
| | - R. M. Thorne
- Department of Atmospheric and Oceanic Sciences; University of California Los Angeles; Los Angeles California USA
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Summers D, Ni B, Meredith NP. Timescales for radiation belt electron acceleration and loss due to resonant wave-particle interactions: 2. Evaluation for VLF chorus, ELF hiss, and electromagnetic ion cyclotron waves. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006ja011993] [Citation(s) in RCA: 305] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Danny Summers
- Department of Mathematics and Statistics; Memorial University of Newfoundland; St. John's Newfoundland Canada
| | - Binbin Ni
- Department of Mathematics and Statistics; Memorial University of Newfoundland; St. John's Newfoundland Canada
| | - Nigel P. Meredith
- British Antarctic Survey; Natural Environment Research Council; Cambridge UK
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