Physics
Scientific paper
May 2009
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009soph..256..443v&link_type=abstract
Solar Physics, Volume 256, Issue 1-2, pp. 443-462
Physics
10
Solar Energetic Particles, Stereo, Magnetic Cloud
Scientific paper
The solar energetic particle event on 14 December 2006 was observed by several near-Earth spacecraft including the Advanced Composition Explorer (ACE), STEREO A and B, SOHO and Wind. An interesting feature of this event is a series of unusual fluctuations in the particle intensity that occurred during the first few hours. These fluctuations were observed inside a magnetic cloud that originated in a solar event on 13 December and show both similarities and variations at the different spacecraft. Interestingly, the most striking difference is between observations at the two closely-separated STEREO spacecraft. In particular, large fluctuations in the proton intensity were seen by the High Energy Telescope (HET) on STEREO A, and to a lesser extent at Wind and ACE, but not by the STEREO B HET. We conclude that the differences in intensity-time profiles were caused by anisotropies in the particle distribution and the different viewing directions of the individual particle telescopes. The intensity/anisotropy variations suggest that flux tubes with different particle propagation conditions existed within this magnetic cloud despite the absence of local magnetic field signatures associated with these regions. The intensity fluctuations are similar to those occasionally seen in impulsive particle events. There were also spacecraft-to-spacecraft differences during the onset of the particle event. An initial rapid onset of energetic (> 40 MeV) protons was observed by the STEREO A and B spacecraft outside the magnetic cloud, but not by spacecraft such as SOHO that were already inside the magnetic cloud at this time. The latter spacecraft observed a slower, lower intensity increase. Evidently, energetic proton propagation from the solar event to the vicinity of Earth was inhibited within the magnetic cloud compared to outside.
Cohen Christina Mae S.
Cummings Alan C.
Leske Richard A.
Mewaldt Richard A.
Reames Donald. V.
No associations
LandOfFree
The Solar Energetic Particle Event of 14 December 2006 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Solar Energetic Particle Event of 14 December 2006, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Solar Energetic Particle Event of 14 December 2006 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1111865