horizontal profile of a moving red line cusp aurora s. taguchi资料.pdf

该【horizontal profile of a moving red line cusp aurora s. taguchi资料 】是由【玉柱儿】上传分享，beplayapp体育下载一共【17】页，该beplayapp体育下载可以免费在线阅读，需要了解更多关于【horizontal profile of a moving red line cusp aurora s. taguchi资料 】的内容，可以使用beplayapp体育下载的站内搜索功能，选择自己适合的beplayapp体育下载，以下文字是截取该文章内的部分文字，如需要获得完整电子版，请下载此beplayapp体育下载到您的设备，方便您编辑和打印。:..PUBLICATIONSJournalofGeophysicalResearch:SpacePhysicsRESEARCHARTICLEHorizontalpro?,34,,,,:1DepartmentofGeophysics,GraduateSchoolofScience,KyotoUniversity,Kyoto,Japan,munication?Asemiquantitativemodelexplainsthe3intensityvariationofamovingredlineEngineeringandInformatics,munications,Tokyo,Japan,CenterforSpaceScienceandRadiocuspauroraEngineering,munications,Tokyo,Japan,4NationalInstituteofPolarResearch,Tokyo,Japan,?Amovingredlinecuspauroradoes5DepartmentofPolarScience,SOKENDAI(GraduateUniversityforAdvancedStudies),Kanagawa,Japannothaveelectronprecipitationinitsrearhalf?(redline),precipitationregionisimportantfordetermininghowtheredlineauroraweshowhowthislongradiativetimecontrolsthehorizontalextentofamovingmesoscaleaurora,(4s)observationsbyanall-skyimageratLongyearbyen,Svalbard,andobservationsbytheEuropeanIncoherentScatterSvalbardRadar(ESR),weexaminedtheSupportingInformation:ary?ic?-skyimagerandtheESRclearly?AnimationS1showthemannerinwhichauroralemissionregionspassedthroughtheradar’s?:edgeofthemovingauroralstructureintersectedtheradar’s?eldofview,,,theESRelectrontemperaturedroppedtothebackgroundlevel,******@-’s?,theauroralemissionintheradar’s?:ursbehindtheelectronTaguchi,S.,,,(2017),Horizontalpro?,,122,3509–3525,ursatapointalongthetrailingedgeoftheelectrondoi:.(redline)isatypicalphenomenoninthedaysidecuspofthehigh-latitudeionosphere[.,Sandholtetal.,1986,1990;Lockwoodetal.,1989;Fasel,1995]osheathelectronsinthemoving?uxtubedri-venbyintermittentreconnection,.,a?uxtransferevent[Haerendeletal.,1978;RussellandElphic,1978].[.,Vorobjevetal.,1975;Sandholtetal.,1990].Thismotioncanbeevenfasterinthelongitudinaldirection[.,Lockwoodetal.,1989;Sandholtetal.,1990;al.,1995;Suzukietal.,2008;Taguchietal.,2009].Themovingredlinecuspauroratypicallyhasalatitudinalextentof100–200km[.,Sandholtetal.,1986,1990]andsometimeshasashorterextentof~50km[.,Sandholtetal.,1990;Oksaviketal.,2004;Taguchietal.,2012].Mostoftheaforementionedstudiesarebasedontheresultsofanall-skyimager,whichisapowerfultoolforobtaininginformationonthetwo-??ectthespatialstructureinsidethepar-,(1D),theO(1D),itslifetimeisreducedto30–80satthetypicalaltitudeoftheaurora,.,250–300km[.,SiplerandBiondi,1972],owingtothequenchingofO(1D)byitsreactionswithN2,O2,?,anyeffectfromtherelativelylonglifetimeof30–:..JournalofGeophysicalResearch:(=1kms1×30s)–80km(=1kms1×80s).×200km,Taguchietal.[2015a]-diatelybehindthemovingFregion-[Taguchietal.,2015a,Figures8aand8b].ThisdelaytimeisconsistentwiththelifetimeofO(1D),whichsuggeststhatthespatialrelationshipobtainedbyTaguchietal.[2015a],-trondensityvolumecreatedbytheprecipitatingelectrons,isrelatedtotherelativelylonglifetimeofO(1D).TheaurorastructureanalyzedinTaguchietal.[2015a],however,,asshownintheirFigure8a,re??,weexaminemultipleeventsofisolatedmovingcuspaurorabyusingauroraimagedatahavinghighertimeresolutionthanthoseusedinTaguchietal.[2015a].Moreover,weinvestigateplasmadatafromtheEuropeanIncoherentScatter(EISCAT)Svalbardradar(ESR),,weshowthelargerhorizontalparedwiththeelectronprecipitationregion,-basedall--skyimagerusesanelectronmultipliercharge-coupleddevice(D)camera(Hamamatsu,C9100-13)withanimagingresolutionof512×512pixels,anditmeasuresemissionsattwowavelengths:,Norway(°°E)sinceOctober2011[Taguchietal.,2012].Duringthe?rstobservationseason,fromOctober2011toFebruary2012,-sentstudy,urredon27November2011,duringthe?rstobservationseason;informationafterthesecondseasonorlaterhasbeenreportedelsewhere[Taguchietal.,2015a,2015b].Wenotethattheimagercanclearlydetectfaintemissionsfrompolarcappatchesinthisexposuretime[Hosokawaetal.,2013a,2013b,2016a,2016b;Sakaietal.,2014].ForESR,weuseddatafromthe42mdishantenna,ic?,ic?-:02UT,?gureindi-catesamesoscaleelongatedauroralstructure,-,theaurorastructuremovedwest-northwestward;atthesametime,-teristicsofalloftheseevents,wewillprovideauroraoverviewsinakeogramformatduringalongerintervaltogetherwiththenear-ic?eld(IMF)-southkeogramreproducedfromall-skyimagesfor0500–0900UTandtheIMFobservationsbytheGeotailspace--:..JournalofGeophysicalResearch:.0nmall-skyimagetakenat0747:,?eld--SandE-Wrepresentthegeographicalnorth-southandeast-westmeridians,(0747:02UT).Duringanintervalfromapproximately0600to0810UT,theequatorwardboundaryoftheaurorawaslocatedatthesouthatzenithangleslargerthan30°,andmanypolewardmovingaurorafeatureswereidenti?,theESR42mradarbeganobservationsat~,wefocusontheintervalofapproximately1h,–2cshowtheXGSM,YGSM,ponentsofIMFdata(15saverage)obtainedbyGeotail,(XGSE,YGSE,ZGSE)=(–,–,),.,BZ(Figure2c),becamenegativeafter~0605UT,andthenegativeBZcontinueduntil~-tiveBZintervals,whichreaf?,BY(Figure2b),hadsmallmagnitudesandpredominantlynegativevaluesduring0500–,,BX(Figure2a),,,whichareobtainedfromtheNASACDAWebservice,paniedwiththechangeoftheBYsignfromnegativetopositiveisevidentat0517UT,whichis48min(=0605UT0517UT)~7cm3and~-SkyImagerandESRFigure3showsthe30sintegratedelectrondensity(Ne)andelectrontemperature(Te)measuredbyESRandthe4sresolutionauroraintensity()obtainedinthedirectionoftheradarbeamduring0700–?lesofNeandTe,respectively,andinFigure3c,theauroralintensity(blackdot)paredwithTe(redline).:..JournalofGeophysicalResearch:.0nmauroralintensityinthenorth-southkeogramfor0500–(a)X,(b)Y,and(c)ZcomponentsoftheIMFintheGSMcoordinateareplotted.(d)Thekeogramisreproducedfromall--skyimagedatashowninFigure1(0747:02UT).fromaltitudesof225–=(red)togetherwiththosefromaltitudesof400kmto500km(blue).=3×(.,0747:02UT)atwhichtheall-,“quiet”intervalthatislongerthan4min(240s).Speci?cally,theauroralintensityexceededtheaverageforthepreceding240sbyatleast150R,(=4+16)–7beganat0702:05,0714:24,0719:29,0727:10,0736:27,0744:51,and0755:07UT,,aswellasinEvents1,5,and7,:..JournalofGeophysicalResearch: