M.E. Wiedenbeck, JPL/Caltech 9 June 20101ACE/SOHO/STEREO/Wind Workshop

9 June 20102ACE/SOHO/STEREO/Wind Workshop Valley 4 He 3 He

9 June 2010ACE/SOHO/STEREO/Wind Workshop3 Which Time Periods are Identified as 3 He Rich? for each 3-day period, plot 3He/4He versus Valley/3He and indicate the number of particles in the 3He mass range by the size of the circle (radius proportional to log(counts)) intervals satisfying all criteria are shaded yellow AHEAD BEHIND

9 June 2010ACE/SOHO/STEREO/Wind Workshop4

9 June 2010ACE/SOHO/STEREO/Wind Workshop5

9 June 2010ACE/SOHO/STEREO/Wind Workshop6 Comments on Automated Identification of 3 He-rich Periods multiple injections with close spacing in time make identification of discrete events difficult—so we focus on 3 He-rich time periods without being concerned with how many events contributed with present choice of parameters, the algorithm located all of the 3 He- rich periods that had been identified by hand, to within a day or two a few periods that had not been identified in the by-hand analysis were also selected; these typically fell close to the threshold value for at least one of the selection criteria—the correctness of these additional identifications needs to be checked by looking at other event characteristics once SEP activity increases and more-intense events are occurring, some modification of parameters will be needed to preferentially select these larger events at solar maximum there will be periods with elevated 4 He intensity (e.g., in the tails of gradual SEP events) when spill-over into the 3 He mass region will degrade the sensitivity for identifying 3 He-rich periods