Matching conditions and Higgs mass upper bounds revisited

Abstract

Matching conditions relate couplings to particle masses. We discuss the importance of one-loop matching conditions in Higgs and top-quark sector as well as the choice of the matching scale. We argue for matching scales ${\mu }_{0,t}\simeq m_t$ and ${\mu }_{0,H}\simeq max[m_t,M_H]$. Using these results, the two-loop Higgs mass upper bounds are reanalyzed. Previous results for $\Lambda \approx$ few TeV are found to be too stringent. For $\Lambda =10^{19}$ GeV we find $M_H<180\pm 4\pm 5$ GeV, the first error indicating the theoretical uncertainty, the second error reflecting the experimental uncertainty due to $m_t=175\pm 6$ GeV.

Comments: 20 pages, 6 figures; uses epsf and rotate macros