by Ravi Dinakar
For FREE pdf paper visit:
http://www.jes2s.com/pdfs/Jan2012/A%20Multi-Spacecraft%20Approach%20to%20Studying%20Auroral%20Kilometric%20Radiation%20Using%20the%20Virtual%20Wave%20Observatory.pdf
Authors:
Huy Lam1*, Teresa Petralli-Mallow2, Leonard Garcia3, and Shing Fung4
Student1, Teacher2: Poolesville High School, 17501 West Willard Road, Poolesville, Maryland 20837
Mentor/Senior Programmer3: NASA/GSFC, Greenbelt, MD 2077
Mentor/Research Astrophysicist4: NASA/GSFC, Greenbelt, MD 2077
*Correspondence: lamhuy@gmail.com
Published in The Journal of Experimental Secondary Science (www.jes2s.com)
According to the analysis of the radio wave spectrograms
captured by the IMAGE, Geotail, Polar, Wind,... more
According to the analysis of the radio wave spectrograms
captured by the IMAGE, Geotail, Polar, Wind, Stereo-A,
and Stereo-B spacecraft, the correlation between the
auroral kilometric radiation (AKR) intensity and the
auroral electrojet (AE) index have been found to be
negatively correlated as well as positively correlated. These
findings raised questions against the present notion that
AKR intensity and the AE index are positively correlated.
Although the original objective of this study was to
establish a set of stable threshold values in the auroral
AE index for AKR detection, the negative correlations
found between the AKR intensity and the AE index made
these threshold calculations unattainable. Furthermore,
this study was the first attempt to establish a set of stable
threshold AE index values associated with AKR using a
multi-spacecraft approach provided by the Virtual Wave
Observatory (VWO). This approach was essential to
ensure that any changes observed in the spacecraft data
were due solely to the AKR source. The whole spectrum
of AKR was analyzed, normally 80-800 kHz in the satellite
spectrograms. The threshold value was determined by
comparing AE index plots of AKR events to corresponding
satellite spectrograms of the events. However, the poor
correlations found through this study indicated that there
may be other drivers affecting the AKR intensity other
than the strength of the auroral electrojet current. Thus, a
future multi-parameter magnetosphere investigation using
other geometric indices, such as the Dst index or the Kp
index in comparison with the AE index and AKR intensity,
could explain how unknown drivers of the AKR intensity
and the AE index synergistically caused the inconsistent
correlations. The understanding of the magnetosphere
conditions, as measured by the AE index, which trigger
the AKR emission is crucial to planetary research
because it provides a mechanism to remotely sense the
state of the Jupiter’s, Saturn’s, Neptune’s, and Uranus’s
magnetospheres.
Download (.3093v1)
