激光場相速度分布與激光加速電子.pdf

1、復(fù)旦大學(xué)碩士學(xué)位論文激光場相速度分布與激光加速電子姓名：袁祥群申請學(xué)位級(jí)別：碩士專業(yè)：粒子物理與原子核物理指導(dǎo)教師：霍裕昆2001.5.8■摘要______—____________________________●—_______—________________—————————————————AbstractBasedonthestudiesofelectrondynamicsinintenselaserfields，weprop

2、oseanewmechanism，CAS(captureandviolentaccelerationscenario)，ofelectronaccelerationbyintenselaserbeaminvacunmThemainworkinthisthesisconsistsoftwopartsOneisthestudyofpolarizationeffectonelectronaccelerationbyintensepulsedl

3、asersTheotherthemoreimportant，isthatfromthestructureoftheGaussianbeam，themechanismunderlyingCASphenomenonisstudiedbymeansofanalyticalcalculationsandnumericalsimulationsInthestudyofthepolarizationeffect，theeffectoflaserpo

4、larizationdirectiononelectroninelasticscatteringandaccelerationwithextra—intenselinearpolarizedpulsedlaserswasstudiedbymeansof3DsimulationoftherelativisticNewton—LorentzequationofmotionIthasbeenfoundthatwhenao10，especial

5、lyao30，theelectronscatteringandaccelerationarefoundtObeverysensitivetothelaserpolarizationdirectionInthepolarizationdirection，theincidentelectroncanbeacceleratedtoGeVbytheCASmechanism，whileinthedirectionperpendiculartoth

6、epolarizationdirection，oneCallnotfindCASelectronsevenifthelaserisverystrongao=100ItmeansthattheponderomotivepotentialmodelCannotbeappliedforsuchextraintenselaserfieldsInstudyingthemechanismofelectronacceleration，wefirstd

7、iscussthereasonwhyanelectroncannotgetnetenergyfromaplanewaveBecausetheelectronvelocityisalwayslessthanthephasevelocityoftheplanewave，theremustbcslippagebetweentheelectronandtheplanewave，andtheenergygotfromtheacceleration

8、phasewillbelostwhentheelectronisslippedintothedecelerationphaseThenwestudiedthecharacteristicsofthephasevelocitydistributionofthelaserfieldbyanalysisthestructureofthefocusedGaussianbeamspropagatinginvacuumAndwefoundthatd