The Higgs boson mass as fundamental parameter of the minimal supersymmetric standard model

In the Minimal Supersymmetric Standard Model (MSSM) the mass of the lightest neutral Higgs boson is determined by the supersymmetric parameters. In the m_h MSSM the precisely measured Higgs boson replaces the trilinear coupling A_t as input parameter. Expressions are derived to extract A_t in a semi-analytical form as a function of the light Higgs boson (pole) mass. An algorithm is developed and implemented at two-loop precision, generalizable to higher orders, to perform this inversion consistently. The result of the algorithm, implemented in the SuSpect spectrum calculator, is illustrated on a parameter set compatible with LHC measurements.