Z ′ Bosons , the NuTeV Anomaly , and the Higgs Boson Mass

Fits to the precision electroweak data that include the NuTeV measurement are considered in family universal, anomaly free U(1) extensions of the Standard Model. In data sets from which the hadronic asymmetries are excluded, some of the Z ′ models can double the predicted value of the Higgs boson mass, from ∼ 60 to ∼ 120 GeV, removing the tension with the LEP II lower bound, while also modestly improving the χ2 confidence level. The effect of the Z ′ models on both mH and the χ2 confidence level is increased when the NuTeV measurment is included in the fit. Both the original NuTeV data and a revised estimate by the PDG are considered. ar X iv :0 90 3. 24 97 v1 [ he pph ] 1 3 M ar 2 00 9 To Lev Okun in honor of his 80’th birthday: a kind and gentle man who does physics as he lives his life, with simple honesty and integrity. Although I have told it before, the story of my first encounter with Lev bears retelling. It was at the 1976 International Conference on High Energy Physics in Tbilisi. Andre Sakharov was not allowed to register for the conference but was told that his presence would be tolerated if he wished to attend informally. While there was doubtless considerable sympathy for Sakharov among many of the Soviet physicists attending the conference, Okun was the only one I saw who dared to associate openly on the streets of Tbilisi with Sakharov during the meeting. In another characteristic decision, in the period following the fall of the Soviet Union, Lev chose to remain in Moscow to help preserve the marvelous school of theoretical physics at ITEP, when he could have accepted offers of more comfortable positions outside of Russia.