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Title: SAPS-associated explosive brightening on the dusk-side: A new type of onset-like disturbance: A new type of onset-like disturbance

Abstract

Quasi-periodic energetic particle injections have been observed at geosynchronous orbit on the dusk-side during a steady magnetospheric convection event. Here, we examine high resolution auroral imager data and ground magnetometer data associated with the first of these injections and conclude that it was not associated with classical substorm signatures. It is proposed that these injections are caused by the explosive non-linear growth of a shear-flow-ballooning instability in the region where sub-auroral polarization streams (SAPS) also occur. It is suggested that interchange will occur preferentially in the low-conductivity SAPS region since the magnetic Richardson number is lowest there and the ‘line-tying’ effect will also be least stabilizing there. We also propose that the observed particle injection signatures and auroral morphology constitute a new type of SAPS-associated explosive ‘onset-like’ disturbance that can occur during intervals of strong convection.

Authors:
ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [2]
  1. Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Center for Nonlinear Studies (CNLS)
  2. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
National Science Foundation (NSF); USDOE
OSTI Identifier:
1412861
Report Number(s):
LA-UR-17-24956
Journal ID: ISSN 2169-9380; TRN: US1800379
Grant/Contract Number:
AC52-06NA25396; ATM-0202303
Resource Type:
Journal Article: 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
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; Heliospheric and Magnetospheric Physics

Citation Formats

Henderson, M. G., Morley, S. K., and Kepko, L. E. SAPS-associated explosive brightening on the dusk-side: A new type of onset-like disturbance: A new type of onset-like disturbance. United States: N. p., 2017. Web. doi:10.1002/2017JA024472.
Henderson, M. G., Morley, S. K., & Kepko, L. E. SAPS-associated explosive brightening on the dusk-side: A new type of onset-like disturbance: A new type of onset-like disturbance. United States. doi:10.1002/2017JA024472.
Henderson, M. G., Morley, S. K., and Kepko, L. E. 2017. "SAPS-associated explosive brightening on the dusk-side: A new type of onset-like disturbance: A new type of onset-like disturbance". United States. doi:10.1002/2017JA024472.
@article{osti_1412861,
title = {SAPS-associated explosive brightening on the dusk-side: A new type of onset-like disturbance: A new type of onset-like disturbance},
author = {Henderson, M. G. and Morley, S. K. and Kepko, L. E.},
abstractNote = {Quasi-periodic energetic particle injections have been observed at geosynchronous orbit on the dusk-side during a steady magnetospheric convection event. Here, we examine high resolution auroral imager data and ground magnetometer data associated with the first of these injections and conclude that it was not associated with classical substorm signatures. It is proposed that these injections are caused by the explosive non-linear growth of a shear-flow-ballooning instability in the region where sub-auroral polarization streams (SAPS) also occur. It is suggested that interchange will occur preferentially in the low-conductivity SAPS region since the magnetic Richardson number is lowest there and the ‘line-tying’ effect will also be least stabilizing there. We also propose that the observed particle injection signatures and auroral morphology constitute a new type of SAPS-associated explosive ‘onset-like’ disturbance that can occur during intervals of strong convection.},
doi = {10.1002/2017JA024472},
journal = {Journal of Geophysical Research. Space Physics},
number = ,
volume = ,
place = {United States},
year = 2017,
month =
}

Journal Article:
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