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198 个结果
  • 简介:WehavecomprehensivelyinvestigatedthefrustratedJ1-J2-J3Heisenbergmodelonasimplecubiclattice.Thismodelallowsthreeregimesofmagneticorder,viz.,(π;π;π),(0;π;π)and(0;0;π),denotedasAF1,AF2,andAF3,respectively.Theeffectsoftheinterplayofneighboringcouplingsonthemodelarestudiedintheentiretemperaturerange.Thezerotemperaturemagneticpropertiesofthismodelarediscussedutilizingthelinearspinwave(LSW)theory,nonlinearspinwave(NLSW)theory,andGreen’sfunction(GF)method.ThezerotemperaturephasediagramsevaluatedbytheLSWandNLSWmethodsareillustrated,andareobservedtoexhibitdifferentparameterboundaries.Incertainregionsandalongtheparameterboundaries,thepossiblephasetransformationsdrivenbytheparametersarediscussed.TheresultsobtainedusingtheLSW,NLSW,andGFmethodsarecomparedwiththoseobtainedusingtheseriesexpansion(SE)method,andareobservedtobeingoodagreementwhenthevalueofJ2isnotclosetotheparameterboundaries.ThegroundstateenergiesobtainedusingtheLSWandNLSWmethodsareclosetothatobtainedusingtheSEmethod.Atfinitetemperatures,onlytheGFmethodisemployedtoevaluatethemagneticproperties,andthecalculatedphasediagramisobservedtobeidenticaltotheclassicalphasediagram.Theresultsindicatethatattheparameterboundaries,atemperature-drivenfirst-orderphasetransitionbetweenAF1andAF2mayoccuralongtheboundaryline.AlongtheAF1-AF3andAF2-AF3boundarylines,AF3islessstablethanAF1andAF2.OurcalculatedcriticaltemperatureagreeswiththatobtainedusingMonteCarlosimulationsandpseudofermionfunctionalrenormalizationgroupscheme.

  • 标签: QUANTIZED SPIN models quantum phase TRANSITIONS
  • 简介:Thesymmetryenergy,whichgovernsmanyphysicalphenomenafromthestructureofexoticnucleitoastrophysicalprocesses,hasmanyramificationsinbothnuclearphysicsandastrophysics.Althoughnuclearsymmetryenergyanditsslopeatthenormaldensityofnuclearmatterhavebeenroughlypinneddown,recentinterpretationsofFOPIandFOPI-LANDdatabydifferenttransportmodelsleadtodivergentconclusionsonthedensity-dependentsymmetryenergyatsupradensities.

  • 标签: Qualitative PROBE NUCLEAR
  • 简介:Thevariationalprinciplesfor1-Dunsteadycompressibleflowinadeformingtubederivedinapreviouspaper^[1]areimprovedessentiallybyreconstructingtheinitial/final-integraltermsaccordingtoanewmethodsuggestedinarecentpaper[2],Asaresult,theinherentshortcomingofvariationalprinciplesofbeingunabletoadmitphysicallyrationalinitial/final-valueconditionsininitial/boundary-valueproblemsissuccessfullyeliminated.Thus,anewtheoreticalbasisforthetime-spacefinite-elementanalysisisprovided.

  • 标签: 一维不定常可压缩流体 变化规律 时间边界条件 流体力学 气体动力学
  • 简介:Wecommunicatemanydifficultiesthatweencounterwhenattemptingtopinpointacommonoriginfortheseveralobservedanomalies[1;2]orassessingtheirtensionwithexistingexclusionlimits.Theseincludesystematicsaffectingtheoperationofthedetectors,ourknowledgeoftheirresponse,astrophysicaluncertainties,andthebroadrangeofparticlecouplingsthatcanmediatetheinteractionwithadetectortarget.Theinterestingastrophysicalevidence[2]thatmotivatesasearchfordark-photonandfocusesourattentiononaHiddenValleysmodelwithaGeV-scaledarksectorthatproducesexcitingsignatures.Resultsfromtherecentundergroundexperiments[1]arealsoconsidered.

  • 标签: RECENT PROGRESS SIGNATURES
  • 简介:Theobservedlossrateofbothparticlesandenergyfromhotconfinedtoroidalplasmasismuchhigherthantheonepredictedbyneoclassicaltransporttheory,whichdependsuponmeanplasmaparametersandCoulombcollisions.Manytypesofplasmaturbulencehavebeenproposedtoexplainanomalousplasmatransport.Thefluctuationofplasmaparametersaroundtheirmeanvaluescancausetransportthroughelectrostaticormagneticfluctuations.Thefluctuationdrivenradialparticlefluxisgivenby

  • 标签: 逃逸扩散系数 HL-1M 磁扰动 能量损失率 平均等离子体参数
  • 简介:Thephotonpolarizationtensorcarriesthefundamentalinformationofmagnetizedvacuumormedium[1{5].Acompletedescriptionofthevacuumpolarizationtensorisparticularlycomplicatedtoapproach,sincethevacuumphotonpolarizationtensorisexpressedintermsofadoublesummationofinfiniteserieswithrespecttotwoLandaulevelsoccupiedbyvirtualchargedparticles.MostworkswerefocusingonthestrongfiledlimitwithanassumptionofLowestLandauLevel(LLL)[2,6]InRef.[7]weobtainedafulldescriptionofvacuumpolarizationtensorinresponsetoalltheLandaulevelsatanyfieldstrengthofBforthefirsttimebeyondLLLapproximation,andwefoundoutthattheimaginarypartofthephotonpolarizationtensorξΠbecomesnonzeroatthetimelikemomentaregionQ2>4(M2+2neB)atT=0,i.e..,theLLLapproximationisanalyticallysatisfied[3,7].

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  • 简介:TheGroupofNuclearStructureResearchatIMPhasdevotedmuchefforttothestudyofin-beam-rayspectroscopyandγ-decayspectroscopy.Oneterminalforin-beam-rayspectroscopyhasbeennewlybuiltupin2016.Asforγ-decayspectroscopy,twopointsneedtobeemphasized.Inordertostudythein-beam-rayspectroscopy,aballwasplacedattheterminalofnewTL2beamline.Threequadrupolemagnetsfollowingthedipolemagnetarethemainbuildingblocksalongthebeamline.Theballconsistsof8cloverand16HPGedetectorswithaCsIballinsidetoselectthechargedparticlechannel.Awallisolatingtheballfromthequadrupoleswasusedtoshieldtheradiationproducedbytheacceleratoranddepositingenergyinthedetectors,whichmayresultinahighbackground.Theinstallationwasfinishedin2016andtheexperimentforin-beam-rayspectroscopyisexpectedtoperformin2017.

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  • 简介:TheGroupofNuclearStructureResearchatIMPhasdevotedmuchefforttothelifetimemeasurementsoflowlyingexcitedstatesvia??fasttimingcoincidence.Twoexperimentswereperformedin2015attheradioactivebeamlineRIBLL[1]andgas-filledrecoilseparatorSHANS[2].

  • 标签: STRUCTURE RESEARCH GROUP
  • 简介:Morelocalizedenergydepositionisabletobeproducedinantiproton-nucleuscollisionsincomparisonwithheavy-ioncollisionsduetoannihilationreactions.Searchingforthecoldquark-gluonplasma(QGP)withantiprotonbeamshasbeenconsideredasahottopicbothinexperimentsandinthereticalcalculationsoverthepastseveraldecades.Strangenessproductionandhypernucleusformationinantiproton-inducednuclearreactionsareimportanceinexploringthehyperon(antihyperon)-nucleon(HN)potentialandtheantinucleon-nucleoninteraction,whichhavebeenhottopicsintheforthcomingexperimentsatPANDAinGermany.

  • 标签: STRANGENESS PRODUCTION ANTIPROTON
  • 简介:Thecomplexbandstructuresofa1Danisotropicgraphenephotoniccrystalareinvestigated,andthedispersionrelationsareconfirmedusingthetransfermatrixmethodandsimulationofcommercialsoftware.Itisfoundthattheresultofusingeffectivemediumtheorycanfitthederiveddispersioncurvesinthelowwavevector.Transmission,absorption,andreflectionatobliqueincidentanglesarestudiedforthestructure,respectively.Omni-gapsexistforanglesashighas80°fortwopolarizations.Physicalmechanismsofthetunabledispersionandtransmissionareexplainedbythepermittivityofgrapheneandtheeffectivepermittivityofthemultilayerstructure.

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  • 简介:我们比较二条双性人标准政策,,为排队的M/G/1有第二种可选的服务的系统,在哪个假期时期的长度也被到达的数字随机在闲散时期期间或由一个定时器控制。在所有顾客用尽一切地在队列被为服务以后,服务者立即度假并且可以操作政策或政策。为二条双性人标准政策,全部的平均成本功能每统一时间被开发寻找至少花费的最佳的静止经营方针。为联合最佳起点值在最佳的费用之上基于明确的形式(p,T)并且(p,N)被获得。

  • 标签: 平均操作成本 优化比较 选择性服务 最佳阈值
  • 简介:Weinvestigateanewclassofperiodicsolutionsto(2+1)-dimensionalKdVequations,byboththelinearsuperpositionapproachandthemappingdeformationmethod.Thesenewperiodicsolutionsaresuitablecombinationsoftheperiodicsolutionstothe(2+1)-dimensionalKdVequationsobtainedbymeansoftheJacobianellipticfunctionmethod,buttheypossessdifferentperiodsandvelocities.

  • 标签: KDV方程 周期解 空间函数 线性叠加
  • 简介:In2014,researchersinthehighenergynuclearphysicsgroupatIMPhavecarriedouttheirresearchworkonhadronphysics.Severalinterestingresultswereobtainedandpublished.Themesonandbaryonexcitedstateshavebeenstudiedinalargenumberofformationandproductionexperiments.Thestudyofmesonresonancesandthesearchforglueballs,hybrids,andmultiquarkstateshaveremainedanactiveandinterestingfieldofhadronphysics,whileforbaryons,theinvestigationofthebaryonspectrumandthebaryoncouplingsfromexperimentaldataarealsothemostimportantissuesinhadronicphysicsandtheyareattractingmuchattention.StudyinghadronresonancesiscrucialtounderstanddeeplytheQCDtheoryatnonperturbativeenergyregion,anditisalsoimportantfornuclearphysicsandparticlephysics.

  • 标签: NUCLEON PHYSICS GROUP