$R_b$-$R_c$ Crisis and the Higgs Boson Mass from LEP Precision Data

Abstract

We study the effects on the Higgs boson mass from LEP precision data of the new physics explaining $R_b$-$R_c$ crisis. We implement a fit to LEP observables with the new physics. We obtain $M_H^{\rm New Physics} = 85 ^{+ 467}_{-56} ~~{\rm GeV}$. Comparing with the value of the SM fit, $M_H^{\rm SM} = 38^{+ 96}_{-21} ~~{\rm GeV}$, the errors are larger and the central value is higher. The new physics may allow $M_H$ to have a value out of the range of ${\cal O}(M_Z)$.