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Title: Information theoretical approach to discovering solar wind drivers of the outer radiation belt

The solar wind-magnetosphere system is nonlinear. The solar wind drivers of geosynchronous electrons with energy range of 1.8–3.5 MeV are investigated using mutual information, conditional mutual information (CMI), and transfer entropy (TE). These information theoretical tools can establish linear and nonlinear relationships as well as information transfer. The information transfer from solar wind velocity ( Vsw) to geosynchronous MeV electron flux ( Je) peaks with a lag time of 2 days. As previously reported, Je is anticorrelated with solar wind density ( nsw) with a lag of 1 day. However, this lag time and anticorrelation can be attributed at least partly to the Je( t + 2 days) correlation with Vsw( t) and nsw( t + 1 day) anticorrelation with Vsw( t). Analyses of solar wind driving of the magnetosphere need to consider the large lag times, up to 3 days, in the ( Vsw, nsw) anticorrelation. Using CMI to remove the effects of Vsw, the response of Je to nsw is 30% smaller and has a lag time < 24 h, suggesting that the MeV electron loss mechanism due to nsw or solar wind dynamic pressure has to start operating in < 24 h. nsw transfers about 36% asmore » much information as Vsw (the primary driver) to Je. Nonstationarity in the system dynamics is investigated using windowed TE. Here, when the data are ordered according to transfer entropy value, it is possible to understand details of the triangle distribution that has been identified between Je( t + 2 days) versus Vsw( t).« less
Authors:
 [1] ;  [2] ; ORCiD logo [3] ; ORCiD logo [4]
  1. The Johns Hopkins Univ. Applied Physics Lab., Laurel, MD (United States)
  2. Princeton Univ., Princeton, NJ (United States); Andrews Univ., Berrien Springs, MI (United States)
  3. Center for Mathematics and Computer Science (CWI), Amsterdam (The Netherlands)
  4. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Publication Date:
Report Number(s):
LA-UR-17-28042
Journal ID: ISSN 2169-9380; TRN: US1703021
Grant/Contract Number:
AC52-06NA25396; AGS-1058456; AC02-09CH11466
Type:
Accepted Manuscript
Journal Name:
Journal of Geophysical Research. Space Physics
Additional Journal Information:
Journal Volume: 121; Journal Issue: 10; Journal ID: ISSN 2169-9380
Publisher:
American Geophysical Union
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
National Aeronautic and Space Administration (NASA); USDOE
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; Heliospheric and Magnetospheric Physics; radiation belt; solar wind drivers; information theory; nonlinear relationships; triangle distribution; mutual information
OSTI Identifier:
1402657
Alternate Identifier(s):
OSTI ID: 1402205

Wing, Simon, Johnson, Jay R., Camporeale, Enrico, and Reeves, Geoffrey D.. Information theoretical approach to discovering solar wind drivers of the outer radiation belt. United States: N. p., Web. doi:10.1002/2016JA022711.
Wing, Simon, Johnson, Jay R., Camporeale, Enrico, & Reeves, Geoffrey D.. Information theoretical approach to discovering solar wind drivers of the outer radiation belt. United States. doi:10.1002/2016JA022711.
Wing, Simon, Johnson, Jay R., Camporeale, Enrico, and Reeves, Geoffrey D.. 2016. "Information theoretical approach to discovering solar wind drivers of the outer radiation belt". United States. doi:10.1002/2016JA022711. https://www.osti.gov/servlets/purl/1402657.
@article{osti_1402657,
title = {Information theoretical approach to discovering solar wind drivers of the outer radiation belt},
author = {Wing, Simon and Johnson, Jay R. and Camporeale, Enrico and Reeves, Geoffrey D.},
abstractNote = {The solar wind-magnetosphere system is nonlinear. The solar wind drivers of geosynchronous electrons with energy range of 1.8–3.5 MeV are investigated using mutual information, conditional mutual information (CMI), and transfer entropy (TE). These information theoretical tools can establish linear and nonlinear relationships as well as information transfer. The information transfer from solar wind velocity (Vsw) to geosynchronous MeV electron flux (Je) peaks with a lag time of 2 days. As previously reported, Je is anticorrelated with solar wind density (nsw) with a lag of 1 day. However, this lag time and anticorrelation can be attributed at least partly to the Je(t + 2 days) correlation with Vsw(t) and nsw(t + 1 day) anticorrelation with Vsw(t). Analyses of solar wind driving of the magnetosphere need to consider the large lag times, up to 3 days, in the (Vsw, nsw) anticorrelation. Using CMI to remove the effects of Vsw, the response of Je to nsw is 30% smaller and has a lag time < 24 h, suggesting that the MeV electron loss mechanism due to nsw or solar wind dynamic pressure has to start operating in < 24 h. nsw transfers about 36% as much information as Vsw (the primary driver) to Je. Nonstationarity in the system dynamics is investigated using windowed TE. Here, when the data are ordered according to transfer entropy value, it is possible to understand details of the triangle distribution that has been identified between Je(t + 2 days) versus Vsw(t).},
doi = {10.1002/2016JA022711},
journal = {Journal of Geophysical Research. Space Physics},
number = 10,
volume = 121,
place = {United States},
year = {2016},
month = {7}
}