Can lepton flavor violating interactions explain the atmosph

We investigate whether flavor changing neutrino interactions (FCNIs) can be sufficiently large to provide a viable solution to the atmospheric neutrino problem. Effective operators induced by heavy boson exchange that allow for flavor changing neutrino sca

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aWIS-99/31/Sept-DPPSLAC-PUB-8244hep-ph/9909390September1999Canlepton avorviolatinginteractionsexplaintheatmosphericneutrinoproblem?SvenBergmann,aYuvalGrossmanbandDamienM.PiercecaDepartmentofParticlePhysicsWeizmannInstituteofScience,Rehovot76100,IsraelbStanfordLinearAcceleratorCenterStanfordUniversity,Stanford,CA94309cBrookhavenNationalLaboratoryUpton,NY11973AbstractWeinvestigatewhether avorchangingneutrinointeractions(FCNIs)canbesu cientlylargetoprovideaviablesolutiontotheatmosphericneutrinoproblem.E ectiveoperatorsinducedbyheavybosonexchangethatallowfor avorchangingneutrinoscatteringo quarksorelectronsarerelatedbyanSU(2)Lrotationtooperatorsthatinduceanomaloustaudecays.Since

SU(2)LviolationissmallforNewPhysicsatorabovetheweakscale,one

canusetheupperboundsonlepton avorviolatingtaudecaysoronlepton

universalityviolationtoputsevere,model-independentboundsontherelevant

non-standardneutrinointeractions.AlsoZ-induced avorchangingneutral

currents,duetoheavysingletneutrinos,aretoosmalltoberelevantforthe

atmosphericneutrinoanomaly.WeconcludethattheFCNIsolutiontothe

atmosphericneutrinoproblemisruledout.