On the Choice of Dispersion Relation to Calculate the QCD Correction to $\Gamma(H\to \ell^+\ell^-)

Abstract

We use the Operator Product Expansion (OPE) of quark vacuum polarization functions to show that the dispersion relation of Kniehl and Sirlin will yield the correct result to all orders in ${\alpha }_s$ when applied to the QCD correction to the leptonic decay width of the Higgs boson.

Comments: 11 pages