operator analysis for the higgs potential and cosmological bound on the higgs-boson mass

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1、UMDHEP93-074OperatorAnalysisfortheHiggsPotentialandCosmologicalBoundontheHiggs-bosonMass†XinminZhangCenterforTheoreticalPhysicsDepartmentofPhysicsUniversityofMarylandCollegePark,MD20742AbstractUsingeffectivefieldtheoryatfinitetemperature,weexaminetheim-pactsofnewphysicsontheelectroweakphasetrans

2、ition.ByanalysingthehighdimensionaloperatorsreleventtotheHiggspotentialwepointoutthatarXiv:hep-ph/9301277v126Jan1993theHiggsmassboundobtainedbyavoidingthewashoutofthebaryonasym-metrycanberelaxedtotheregionallowedbyexperiments,providedthatnewphysicsappearsattheTeVscale.†Worksupportedbyagrantfr

3、omtheNationalScienceFoundation1ItisgenerallyrealizedthatbaryogenesisatelectroweakscalerequiresnewphysicsbeyondthestandardmodelsinceCPviolationinthestandardmodelistoosmalltoyieldanythingliketheobservedasymmetry.Further-more,inthestandardmodeltheupperlimitoftheHiggsmassobtainedbyavoidingwashout

4、oftheasymmetryproducedduringphasetransitionliesbe-lowthepresentexperimentallowerbound.IndealingwiththeCPproblem,onepossibilitytoyieldsufficientCPviolationistoaddhighdimensionaloperatorstothestandardmodellagrangian[F.1].Generallytherearetwooperatorsinthelowestdimension:φ2O=TrWW˜µν,(1)1Λ2µνφ2O=Tr

5、GG˜µν,(2)2Λ2µνwhereφistheneutralcomponentoftheHiggsdoubletH,whichdevelopsavacuumexpectationvalue(v≃250GeV),GµνandWµνarethefieldstrengthoftheSU(3)candSU(2)L,respectively.TheoperatorO1hasbeenexaminedinRef.[5]andO2inRef.[7]withsimplereplacementofthesingletfieldbyφ2.Theresultsshowthattheobservedbar

6、yonasymmetrycanbeproducedatweakscaleprovidedthatthenewphysicsscaleΛisofO(TeV).Moreover,thepredictedvaluesoftheelectricdipolemomentsofneutronandelectronareveryclosetotheexperimentallimits[8].Thisapproachtoelectroweak[F.1]Otherpossibilitieshavealsobeensuggestedsuchasaxionmodels[1],thesingletmaj

7、oronmodels[2],thetwo-Higgsmodels[3],theSUSYmodels[4][5]andleft-rightsymmetricmodels[6].2baryogenesisisbasedontheeffectivelagrangianmethod[F.2],namelytheeffectsofnewphysicsbeingaccountedforbyaddingtothestandardmodellagrangianasetoflocaloperators