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This content will become publicly available on September 10, 2017

Title: The relationship between the plasmapause and outer belt electrons

Here, we quantify the spatial relationship between the plasmapause and outer belt electrons for a 5 day period, 15–20 January 2013, by comparing locations of relativistic electron flux peaks to the plasmapause. A peak-finding algorithm is applied to 1.8–7.7 MeV relativistic electron flux data. A plasmapause gradient finder is applied to wave-derived electron number densities >10 cm–3. We identify two outer belts. Outer belt 1 is a stable zone of >3 MeV electrons located 1–2 RE inside the plasmapause. Outer belt 2 is a dynamic zone of <3 MeV electrons within 0.5 RE of the moving plasmapause. Electron fluxes earthward of each belt's peak are anticorrelated with cold plasma density. Belt 1 decayed on hiss timescales prior to a disturbance on 17 January and suffered only a modest dropout, perhaps owing to shielding by the plasmasphere. Afterward, the partially depleted belt 1 continued to decay at the initial rate. Belt 2 was emptied out by strong disturbance-time losses but restored within 24 h. For global context we use a plasmapause test particle simulation and derive a new plasmaspheric index Fp, the fraction of a circular drift orbit inside the plasmapause. We find that the locally measured plasmapause is (for thismore » event) a good proxy for the globally integrated opportunity for losses in cold plasma. Our analysis of the 15–20 January 2013 time interval confirms that high-energy electron storage rings can persist for weeks or even months if prolonged quiet conditions prevail. This case study must be followed up by more general study (not limited to a 5 day period).« less
Authors:
 [1] ;  [2] ;  [3] ;  [4] ;  [5] ;  [2] ;  [1] ;  [4] ;  [4] ;  [6] ;  [5] ;  [7]
  1. Southwest Research Institute, San Antonio, TX (United States); Univ. of Texas, San Antonio, TX (United States)
  2. Univ. of Colorado, Boulder, CO (United States)
  3. The Aerospace Corp., Los Angeles, CA (United States)
  4. Univ. of Iowa, Iowa City, IA (United States)
  5. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  6. UCLA, Los Angeles, CA (United States)
  7. Univ. of New Hampshire, Durham, NH (United States)
Publication Date:
OSTI Identifier:
1325657
Report Number(s):
LA-UR--16-25977
Journal ID: ISSN 2169-9380
Grant/Contract Number:
AC52-06NA25396
Type:
Accepted Manuscript
Journal Name:
Journal of Geophysical Research. Space Physics
Additional Journal Information:
Journal Name: Journal of Geophysical Research. Space Physics; Journal ID: ISSN 2169-9380
Publisher:
American Geophysical Union
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
NASA; USDOE
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS heliospheric and magnetospheric physics