SUSY QCD Corrections to Higgs-b Production : Is the Δ_b Approximation Accurate?

The associated production of a Higgs boson with a b quark is a discovery channel for the lightest MSSM neutral Higgs boson. We consider the SUSY QCD contributions from squarks and gluinos and discuss the decoupling properties of these effects. A detailed comparison of our exact order(alpha_s) results with those of a widely used effective Lagrangian approach, the \Delta_b approximation, is presented. The \Delta_b approximation is shown to accurately reproduce the exact one-loop SQCD result to within a few percent over a wide range of parameter space.

Comments: figures added, version to be published in Phys Rev D

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Affiliations: 1NIKHEF, Amsterdam & Leiden U., 2NIKHEF, Amsterdam, 3NIKHEF, Amsterdam

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