AIREX: Greater than 25 Mev Proton Events Observed by the High Energy Telescopes on the STEREO A and B Spacecraft and-or at Earth During the First Approximately Seven Years of the STEREO Mission

タイトル	Greater than 25 Mev Proton Events Observed by the High Energy Telescopes on the STEREO A and B Spacecraft and-or at Earth During the First Approximately Seven Years of the STEREO Mission
本文（外部サイト）	http://hdl.handle.net/2060/20150007709
著者（英）	von Rosenvinge, Tycho T.; Leske, R. A.; Mewaldt, R. A.; Wiedenbeck, M. E.; Stone, E. C.; Cane, H. V.; Richardson, Ian G.; Cohen, C. M. S.; Christian, E. R.; Labrador, A. W.
著者所属（英）	NASA Goddard Space Flight Center
発行日	2014-04-15
言語	eng
内容記述	Using observations from the High Energy Telescopes (HETs) on the STEREO A and B spacecraft and similar observations from near-Earth spacecraft, we summarize the properties of more than 200 individual greater than 25 MeV solar proton events, some detected by multiple spacecraft, that occurred from the beginning of the STEREO mission in October 2006 to December 2013, and provide a catalog of these events and their solar sources and associations. Longitudinal dependencies of the electron and proton peak intensities and delays to onset and peak intensity relative to the solar event have been examined for 25 three-spacecraft particle events. Expressed as Gaussians, peak intensities fall off with longitude with sigma = 47 +/- 14 deg for 0.7 - 4 MeV electrons, and sigma = 43 +/- 13 deg for 14 - 24 MeV protons. Several particle events are discussed in more detail, including one on 3 November 2011, in which is approx. 25 MeV protons filled the inner heliosphere within 90 minutes of the solar event, and another on 7 March 2012, in which we demonstrate that the first of two coronal mass ejections that erupted from an active region within is approx. 1 hour was associated with particle acceleration. Comparing the current Solar Cycle 24 with the previous cycle, the first greater than 25 MeV proton event was detected at Earth in the current solar cycle around one year after smoothed sunspot minimum, compared with a delay of only two months in Cycle 23. Otherwise, solar energetic particle event occurrence rates were reasonably similar during the rising phases of Cycles 23 and 24. However, the rate declined in 2013, reflecting the decline in sunspot number since the peak in the northern-hemisphere sunspot number in November 2011. Observations in late 2013 suggest that the rate may be rising again in association with an increase in the southern sunspot number.
NASA分類	Solar Physics
レポートNO	GSFC-E-DAA-TN22276 GSFC-E-DAA-TN22507
権利	Copyright, Distribution as joint owner in the copyright