等离子体在任意强度的直流电场中产生电流的过程

*翁苏明1)盛政明1)2)­张杰1)2)1)(,,100190)2)(,200240)(2008731;2008923)Fokker-Planck,.,.,Spitzer,;,MaxwellMaxwell,.,,Spitzer,.Spitzer.:,,Fokker-Planck,SpitzerPACC:5265,5220,5220F,5225D*(:10425416,10674175,60621063)(:2007CB815101,2007CB815105).­.E-mail:[e-mail]11引言,.,,Spitzer[1].,Spitzer[2].,,Maxwell[3]Maxwell[4].Maxwell,Spitzer[5];Maxwell[6].,..,[7].,[8],[9)11].,.-Fokker-Planck[12],.,[13].,,Spitzer,.,MaxwellMaxwell,,,.,,Spitzer58122009121000-3290P2009P58(12)P8454-07ACTAPHYSICASINICAVol.58,No.12,December,2009n2009Chin.Phys.Soc.,.,Spitzer.21等离子体中的Fokker-Planck方程,Fokker-Planck[12,13]:9fe9t=eEm#$vfe+Cei(fe)+Cee(fe),(1)E,-Cei(fe)-Cee(fe)[12]Cei(fe)=-$v#(-De|iHHeHeH#$vfe),(2)Cee(fe)=-$v#(-De|e#$vfe+Fe|efe).(3),(1)Fokker-Planck[12],.,(1).De|eDe|i,;Fe|e-eEPm,.,Maxwell.,.1,MaxwellvL=0,Fe|ev,De|eHHDe|iHHvM.Fe|eveEcPZime,De|eHHeEcve0PZime,De|iHHeEcve0Pme,Ec=meve0MeiPe,-Mei=Zi#e|ePv3e0=1PSei,ve0.Zi=1,--,-,.1,De|iHH011eEcve0Pme,011Ec,Ec.1MaxwellvL=0,Fe|ev,De|eHH,De|iHH,Maxwell0.1Ec50SeiFe|evvMFe|eveEcPZime,De|eHHeEcve0PZime,De|iHHeEcve0Pme31等离子体电流与电场的关系3111fe(v,H)=E]l=0fel(v)Pl(cosH)Legendre,,Maxwellfe(v,H)DfeM(v)+fe1(v)cosH.Fokker-Planck(1),,0=eEm#$vfeM+(De|eHH+De|iHH)2fe1(v)cosHv2.(4)JU-eQvcosHfe1(v)cosHdv=4PeveE3EcQ]0De|iHHDe|eHH+De|iHHv7v5efeM(v)dv.(5)Zim1,LorentzDe|eHHnDe|iHH,(5)RL=JPE=322Pnee2meMieU12177nee2meMie.(6)845512:Zi,RZ=CZRL,(7)CZ:CZ=(2P)3P248neQ]0De|iHHDe|eHH+De|iHHv7v5efeM(v)dv.(8)Fokker-Planck,2.2E=1@10-8Ect100SeiJPEnee2PmeMie2,Zi,Lorentz.1RZCZ,Spitzer[1].,Maxwell,(5),;,Maxwell,.1-1PeSr1,1PeSr2(e).1Sr1Sr2,,.1RZCZSr1Sr2ZiRZ(nee2PmeMie)CZSr1(Sei)Sr2(Sei)1713901579817816281740168410191018101112001877151715171001212001955171918133121,0101Ec,011Ec110Ec,3.,Et.-,Zi=1Zi=]..,.-.,,.,.Zi=1,-,3(c).,Maxwell,Maxwell,.,MaxwellMaxwell,Maxwell,Maxwell.:-v=0;-,,-Maxwell.1,011Ec50Sei,Fe|evvM=-2ve0;vM-2ve0Fe|ev845658,vM-2ve0.Fe|ev,3(d)-.,-Maxwell,Maxwell.,-v=0.-De|iHHW1Pvv=0,3(f)v=0.3(e),-v=0-,-Maxwell.3(a)(b)0101Ec500Sei,(c)(d)011Ec50Sei,(e)(f)110Ec5Sei;(a),(c)(e)Zi=1,(b),(d)(f)Zi=].nePv3e0,--,MaxwellMaxwell,fe(v)=DfM(v)+(1-D)fd(v),(9)DMaxwell,MaxwellfM(v)Maxwellfd(v)fM(v)=ne(2Pv2te1)3P2exp-v22v2te1,(10)fd(v)=ne(2Pv2te2)3P2exp-(v-vd)22v2te1.(11)MaxwellJM=D[1-exp(-tPSr1)]R0(vte1Pv0)3E.(12)R0=CZRL(7)v0Spitzer.MaxwellJd=-(1-D)eQvfd(v)dv=-(1-D)enevd.(13)TM=meQfe(v)v2MdvTL=meQfe(v)v2LdvP2,(9)TMPme=Dv2te1+(1-D)(v2te2+v2d),(14)TLPme=Dv2te1+(1-D)v2te2,(15)(1-D)v2d=(TM-TL)Pme.(16)(16)vd,TMmTLMaxwellMaxwell1-DmD,vdD[(TM-TL)Pme]1P2;Maxwell845712:,vdD[(TM-TL)Pme]1P2.,MaxwellMaxwell,(15)vte1=vte2=(TLPme)1P2.,MaxwellDDexp[-(mev2dPTL)].J=R0E1-exp-tSr1exp-TM-TLTLTLT03P2+nee1-exp-TM-TLTLTM-TLme1P2.(17)[3][14],dTMPdt=2JE-2Mei(veff)(TM-TL),(18)dTLPdt=Mei(veff)(TM-TL),(19)Mei(veff)=Zi#e|ePv3eff-,veff=(TM+2TL)Pme.TM=TL=T,(17))(19)Spitzer:J=R0E1-exp-tSr1TT03P2,(20)dTdt=23JE.(21)4Zi=10101Ec,011Ec,110Ec(17))(19)011(H),Spitzer011(S),Fokker-Planck011(F).EtEcSei,JPEnee2SiePme,(17))(19),.,,4.,Spitzer.,.5.5,0101Ec,,5Zi=10101Ec,011Ec,110EcEt5SeiEcEtEcSei,JPEnee2SiePme,,RWT3P2e,.,,,,.Et5SeiEc,,,Maxwell;,.,3TMTM,-,(18),(19)TMTL,845858.3131.20LmJf=315GADT,500eV10g#cm-3,[8].,3121@1010VPm,011048Ec.4,620LmJf=315GA500eV10gPcm3DT,Fokker-Planck(17)EF(17))(19)EHSpitzerESSpitzer.6.6,Spitzer,,.(17))(19),.41结论,.,,Spitzer,;,,Maxwell,Maxwell,.,,Spitzer.,,Spitzer.[1]SpitzerL,H¾rmR1953Phys.Rev.89977[2]BenageJF,ShanahanWR,MurilloMS1999Phys.Rev.Lett.832953[3]DreicerH1959Phys.Rev.115238[4]SinghN1978PlasmaPhys.20927[5]KulsrudRM,SunYC,WinsorNK,FallonHA1973Phys.Rev.Lett.31690[6]ShkrarofskyIP,ShoucriMM,FuchsV1992Comput.Phys.Commun.71269[7]TabakM,HammerJ,GlinskyME,KruerWL,WilksSC,WoodworthJ,CampbellEM,PerryMD,MasonRJ1994Phys.Plasmas11626[8]HonrubiaJJ,Meyer-ter-VehnJ2006Nucl.Fusion46L25[9]BellAR,KinghamRJ2003Phys.Rev.Lett.91035003[10]DongYL,ZhaoB,ZhengJ2007Chin.Phys.163742[11]LuoZM,TengLJ1982ActaPhys.Sin.311166(inChinese)[1982311166][12]WengSM,ShengZM,HeMQ,WuHC,DongQL,ZhangJ2006Phys.Plasmas13113302[13]WengSM,ShengZM,HeMQ,ZhangJ,NorreysPA,SherlockM.RobinsonAPL2008Phys.Rev.Lett.100185001[14]GoldstonRJ,RutherfordPH1995IntroductiontoPlasmaPhysics(Bristol:InstituteofPhysicsPublishing)p147845912:Generationofplasmacurrentunderarbitrarystrongdirectcurrentelectricfield*WengSu-Ming1)ShengZheng-Ming1)2)­ZhangJie1)2)1)(BeijingNationalLaboratoryofCondensedMatterPhysics,InstituteofPhysics,ChineseAcademyofSoiences,Beijing100190,China)2)(DepartmentofPhysics,ShanghaiJiaotongUniversity,Shanghai200240,China)(Received31July2008;revisedmanuscriptreceived23September2008)AbstractThegenerationofplasmacurrentandtheevolutionofelectrondistributionunderarbitrarilystrongdirectcurrentelectricfieldshavebeenstudiedbyFokker-Plancksimulation.Itisfoundthatthebehaviorsofplasmaaredifferentunderdifferentfields:intheweakfield,Spitzer.slawissuitablefordescribingtherelationshipbetweenplasmacurrentandelectricfield,andtheresponsetimetogeneratecurrentisapproximatelyequaltotherelaxationtimetoreducecurrentafterswitchingofftheelectricfield;inthemoderatefield,theelectrondistributioniswellrepresentedbythesumofastationa