HIGHER-ORDER CORRECTIONS IN THE SM HIGGS SECTOR - THE RIGHT SCALE

The evaluation of high-energy cross sections involving the SM Higgs bo son requires the use of the Higgs running coupling lambda(mu). Taking mu to be equal to the center-of-mass energy root s of the scattering p rocess, the perturbative approach fails for relatively small values of the Higgs mass and coupling, lambda(root s) approximate to 2.2. Perfo rming an approximates resummation of ''bubble'' Feynman diagrams, we f ind the scale mu = root s/e approximate to root s/2.7 to yield reliabl e perturbative results, even for large Higgs mass and coupling. The ne w perturbative upper limit on the Higgs running coupling is lambda(roo t s/e) approximate to 4.