O(alpha_s^2) corrections to fermionic Higgs decays in the MSSM

Understand

We compute the two-loop corrections of O(alpha_s^2) to the Yukawa couplings in the framework of the Minimal Supersymmetric Standard Model (MSSM).

• The calculation is performed using the effective Lagrangian approach under the approximation of neglecting the Higgs boson mass with respect to the top quark, gluino and all squark flavour masses.
• As an application we derive the O(alpha_s^2) corrections to the partial decay width of the lightest Higgs boson to a bottom quark pair.
• We find that the two-loop corrections are sizable for large values of tan_beta and low CP-odd Higgs boson mass.