HR: 1340h
AN: SM23A-0478 [Abstracts]
TI: Correlation between Low Frequency AKR and Auroral Structures
AU: Pazamickas, K
EM: kbzap@msn.com
AF: St. Monica School, 109 Market St., Sunbury, PA 17801
United States
AU: * Green, J L
EM: James.Green@nasa.gov
AF: NASA Goddard Space Flight Center, Code 630, Greenbelt, MD 20771
United States
AU: Gallagher, D L
EM: dennis.gallagher@msfc.nasa.gov
AF: NASA Marshall Space Flight Center, Code SD50, Huntsville, AL 35812
United States
AU: Mende, S
EM: mende@ssl.berkeley.edu
AF: U. C. Berkeley, Space Sciences Laboratory, Berkeley, CA 94720
United States
AU: Frey, H U
EM: hfrey@ssl.berkeley.edu
AF: U. C. Berkeley, Space Sciences Laboratory, Berkeley, CA 94720
United States
AB:
Auroral Kilometric Radiation (AKR), a radio emission with a broadband frequency range, has long been associated with auroral
activity. Recently we have done a preliminary study of AKR related very low frequency events (hear after referred to as LF
AKR) and their association to specific auroral structures. LF AKR events are characterized as a rapid extension of AKR
related emissions to 30 kHz or lower in frequency for typically much less than 10 minutes. We have extended the previous
study to include all instances of LF AKR events during the nearly 4 years of observations from the IMAGE spacecraft's Radio
Plasma Imager (RPI) instrument. We will discuss the possibility of a correlation between low frequency AKR emissions and the
bifurcation in the aurora by examining images of the auroral oval from the Far Ultraviolet (FUV) instrument on IMAGE. We
will examine the relationship of LF AKR emissions events and other factors including dipole tilt, Dst and AE Index . Although
we don't expect LF AKR to be the only factor in the bifurcated auroral structures, we do expect that this bifurcation will
occur in every instance when LF AKR is observed. The unique character of LF AKR is a possible indicator of specific processes
sometimes occurring during storm-time conditions, resulting from narrow field-aligned density cavities forming at a distance
of perhaps 5-6 RE tailward from the Earth.
DE: 2712 Electric fields (2411)
DE: 2772 Plasma waves and instabilities
SC: SPA-Magnetospheric Physics [SM]
MN: 2004 AGU Fall Meeting