左右對稱模型中的正反物質(zhì)不對稱.pdf

1、中國科學技術大學碩士學位論文左右對稱模型中的正反物質(zhì)不對稱姓名：劉洪歡申請學位級別：碩士專業(yè)：理論物理指導教師：楊為民20090501ABSTRACTl“heongmofmatterantimatterasymmetryisoneofthemostchallengingprob1emsinelementaryparticlephysicsandcosmologyToproducebaryonnumberfromaB=0universe，

2、weneedadynamicalmechanismtoproducebaryonasymmetryintheevolvementoftheuniverseBaryogenesisviaLeptogenesisissuchadynamicalmechamsmofproducingbaryonasymmetryandhasgainedsignificantattentionsincethediscoveryofnon。zeroneutnno

3、massesInthisthesis，westudytheleptonmixinganglesandleptogenesisintheleftrightsymmetricmodelByconsideringquarkandleptonsymmetrymD”muandquarkleptoncomplementarityrelations：012p是≈45。and023％≈45。，weassumethebimaximalmixingmatr

4、ixexistingchargedIep—tonsectorandUcKuexistinginneutrinosectorWiththisassumption，leptonmixingmatrixwith23nearmaximal，12largeand13smallmixingisobtainedThen。wediscussseveralsourcesofC尸一asymmetryinrighthandedneutrinodecay，th

5、ereinto，anewradiativecorrectiondiagraminvolvingright—handedtripletHiggsareintroduced，whichcanmakelargecontributiontothetotalCPasymmetryWealsopropose&flavorsymmetrybasedonthesupersymmetricSU(51grandunifiedmodelInthismodel

6、，fermionsareassignedtoS4antisymmetricrepresentation32ThefermionmassesarefromtheYukawacouplingsinvolvingHiggsmuhipletsbe10ngingtosu(5)representations1，5，57and45，andthestructuresofmassmatricesaIedeterminedbythe64flavorsymm

7、etryWeintroducerighthandedneutrinosandthenlightneutrinomassespurelycomefromthetypeIseesawmechanismAftersymmetrybroken，weobtainedtheferrnionmassmatricescontainingparameterswhicharelessthantheinputvaluesThenumericalresults

8、offermionmassesandmixingmatricesareinaccordwiththeexperimentalresultsAtlast，wediscussthebaryogenesisinaflewextendedleftrightsymmetricgrandunifiedmodelwithS0(3)flavorsymmetryInthismodel，newisospinsu(2)groupandnewsuperheav

9、yfermionsasmirrorsoflowenergyfermionsareintroducedTheDiractypeYukawacouplingsofneutrinosaretoosmall，SOthattheCPasynlmetⅣproducedbythedecayofrighthandedneutrinosarenotlargeenoughtoprodUCgsufficientbaryon’asymmetryThen，dec