Ineddltlon tothepreviously reported mean Ionic charge ofIronin3He-rich solar flareswehave for thefirst timedetermined theaverage mean charge of5111con for223He-rlch periods during thetimeInterval fromSeptember 1978to October 1979 TheresultsIndicate thatthevalueof themean charge stateof Siliconis higherthanthe normal flare average by approximately 3 units and mpartmular it ishigher than thevalue predicted byresonant heatmg models for3He-rich solar flares !, Introduction. The 3He isotope was fast measured asa consbtuent of solarenergetm pertmle events In 1970byHsleh and Simpson 1.Following thisdiscovery, it has bean firmlyestablished bynow that thereexists oclass ofgenerally small solarflareevents Inwhich theabundance of the3Heisotope relative to4Heinsolarcosmic raysisgreatly enhanced relative tothenormal solarabundance ratms. Enrichments of more then fourorders ofmagnitude have been observed, leedmg toa:3He/4He ratioof;: 1 These unusually highenrichment factors canbest beexpiuined bye two-stage acceleratmn process withe first step highly selective m mass percharge anda second step actmg onlyupon parhcles above acertmn threshold mrigidityor velocity ,Several plesmo heatmg processes have been proposed asthefirst stage (2,3,4,5), whmh prefepentmlly heat certain minorIonspecies 11ke 3HeTheeffectof thepreferential heatmg w111 bemost pronounced Inthetalloftheiondmtribution function Thesecond stage ecceleratmn process will then (apartfrom mtroducing additional abundance changes, see 6) mealyreflect theabundance ratmsinthetailsoftheiondmtribution functmns In all oftheproposed heating processes the runic charge states playe crihcelrolefor thelargest attainable particlevelocity and/or the heating rate Measurements of thecharge states of energetic runsm 3He-rmhevents are therefore crucml m understandmg thenature of theenrmhment process Forrecent revmws of observational and theorehcal aspects of 3He-richflares see e.o7,8. ;_.Instrument endDote ,Analysis. Thedata presented In thlspaperhove been obtmned during theperiod fromSeptember 1978toOctober 1979withtheI'lax-Plenck-lnshtut / Umvermty ofHoryiand ULEZEQ Sensor onbcerd theISEE-3spacecraft (seealso8) Themstrument is described inmore detail by Hovestedt eta] 10.Weperformed thecharge analysis ofFeand Si for 22 periods richin 3Heasdetermined froma aystematlC study ofthecomposltmn of solar energetic pertmles withourwideangle particle telescope (ULEWAT) onthesame spacecraft Weselected permds witha 3He/4He ratioof _ 0 !, lasting more thanoneday. Theaverage 3He/4Heratioofoil22 periods is0.227.The energy range forwhich thecharge analysis for 5| andFeIs performed, ls 0.55-:3.0and0.34-1.8 HeV/Nrespectively. Thlsrepresents a compromise between elemental and charge resolution and counting statistics 285

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