The SM as the quantum low-energy effective theory of the MSSM

In the framework of the minimal supersymmetric standard model we compute th e one-loop effective action for the electroweak bosons obtained after integ rating out the different sleptons, squarks, neutralinos and charginos, and present the result in terms of the physical sparticle masses. In addition w e study the asymptotic behavior of the two-, three- and four-point Green's functions with external electroweak bosons in the limit where the physical sparticle masses are very large in comparison with the electroweak scale. W e find that in this limit all the effects produced by the supersymmetric pa rticles can either be absorbed in the standard model parameters and gauge b osons wave functions, or else they are suppressed by inverse powers of the supersymmetric particle masses. This work, therefore, completes the proof o f decoupling of the heavy supersymmetric particles from the standard ones i n the electroweak bosons effective action and in the sense of the Appelquis t-Carazzone theorem; we started this proof in a previous work. From the poi nt of view of effective field theories this work can be seen as a (partial) proof that the SM can indeed be obtained from the MSSM as the quantum low- energy effective theory of the latter when the SUSY spectra are much heavie r than the electroweak scale.