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Role of the Russell-McPherron Effect in the Acceleration of Relativistic ElectronsWhile it is well known that high fluxes of relativistic electrons in the Earth's radiation belts are associated with high-speed solar wind and its heightened geoeffectiveness,less known is the fact that the Russell McPherron(R M) effect strongly controls whether or not a given high-speed stream is geoffective. To test whether it then follows that the R M effect also strongly controls fluxes of relativistic electrons, we perform a superposed epoch analysis across corotating interaction regions (CIR) keyed on the interfaces between slow and fast wind. A total of 394 stream interfaces were identified in the years 1994-2006. Equinoctial interfaces were separated into four classes based on the R-M effect,that is, whether the solar wind on either side of the interface was either(geo)effective (E) or ineffective (I) depending on season and the polarity of the interplanetary magnetic field (IMF). Four classes of interface identified as II, IE, EI,and EE are possible. The classes IE and EI correspond to CIRs with polarity changes indicating passage through the heliospheric current sheet. To characterize the behavior of solar wind and magnetospheric variables, we produced maps of dynamic cumulative probability distribution functions (cdfs) as a function of time over 10-day intervals centered on the interfaces. These reveal that effective high-speed streams have geomagnetic activity nearly twice as strong as ineffective streams and electron fluxes a factor of 12 higher. In addition they show that an effective low-speed stream increases the flux of relativistic electrons before the interface so that an effective to ineffective transition results in lower fluxes after the interface.We conclude that the R-M effect plays a major role in organizing and sustaining a sequence of physical processes responsible for the acceleration of relativistic electrons.
Document ID
20100015565
Document Type
Reprint (Version printed in journal)
Authors
McPherron, R. L. (California Univ. Los Angeles, CA, United States)
Baker, D. N. (Colorado Univ. Boulder, CO, United States)
Crooker, N. U. (Boston Univ. Boston, MA, United States)
Date Acquired
August 24, 2013
Publication Date
January 1, 2010
Publication Information
Publication: Journal of Atmospheric and Solar-Terrestrial Physics
Volume: 71
ISSN: 1364-6826
Subject Category
Solar Physics
Funding Number(s)
CONTRACT_GRANT: NNG04GA93G
CONTRACT_GRANT: NSF ATM-0120950
Distribution Limits
Public
Copyright
Other