Physics – Plasma Physics
Scientific paper
Dec 2010
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010agufmsh42b..03t&link_type=abstract
American Geophysical Union, Fall Meeting 2010, abstract #SH42B-03
Physics
Plasma Physics
[7513] Solar Physics, Astrophysics, And Astronomy / Coronal Mass Ejections, [7514] Solar Physics, Astrophysics, And Astronomy / Energetic Particles, [7807] Space Plasma Physics / Charged Particle Motion And Acceleration, [7984] Space Weather / Space Radiation Environment
Scientific paper
As demonstrated by numerous studies in Solar Cycle 23, temporal evolution in elemental composition is a powerful tool for investigating the acceleration and transport processes that govern large, gradual solar energetic particle (SEP) events. Extending such studies to simultaneous observations at widely-separated spacecraft is a key objective of the STEREO mission. However, as of August 2010, the Sun has not produced any sufficiently large SEP events to facilitate such studies. We have therefore undertaken comparisons of simultaneous SEP observations near Earth (by Wind, ACE, and GOES) and at Ulysses. Specifically, we have examined several large SEP events in late 2001, when Ulysses was beyond 2 AU and at high northern solar latitudes, immersed in the fast solar wind. Although the collecting power of the COSPIN/Low Energy Telescope (LET) on Ulysses is only ˜1% as large as that of solar heavy-ion instruments on ACE and Wind (and ˜10% as large as those on STEREO), it nevertheless has provided statistically-meaningful measurements in these events. We compare time evolution in the Fe/O ratio, as well as proton spectra and intensities, and examine how well systematic differences between Ulysses and the near-Earth measurements can be explained by a SEP transport model (Ng, Reames, & Tylka 2003). We also examine solar ions and their spectra in the late decay phase of events, in the so-called “reservoir” regions. We discuss implications of these observations for models of SEP transport. Supported by NASA under grants NNH09AK79I and NNX09AU98G and by European Commission Grant FP7-COMESEP.
Malandraki O.
Marsden Richard G.
Ng Chee K.
Tranquille Cecil
Tylka Allan J.
No associations
LandOfFree
Simultaneous Observations of Evolution in SEP Elemental Composition on Widely-Separated Spacecraft: Comparisons between Ulysses and ACE/Wind in Late 2001 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 Simultaneous Observations of Evolution in SEP Elemental Composition on Widely-Separated Spacecraft: Comparisons between Ulysses and ACE/Wind in Late 2001, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Simultaneous Observations of Evolution in SEP Elemental Composition on Widely-Separated Spacecraft: Comparisons between Ulysses and ACE/Wind in Late 2001 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1510498