====== TTP05-14 Two-Loop matching coefficients for the strong coupling in the MSSM ======
 
 
   <hidden TTP05-14  Two-Loop matching coefficients for the strong coupling in the MSSM > When relating the strong coupling $\alpha_s$, measured at the scale of the
 $Z$ boson mass, to its numerical value at some higher energy, for example
 the scale of Grand Unification, it is important to include higher order
 corrections both in the running of $\alpha_s$ and the decoupling of the
 heavy particles. We compute the two-loop matching coefficients for
 $\alpha_s$ within the Minimal Supersymmetric Standard Model (MSSM) which are
 necessary for a consistent three-loop evolution of the strong coupling
 constant. Different scenarios for the hierarchy of the supersymmetric scales
 are considered and the numerical effects are discussed. We find that the
 three-loop effects can be as large as and sometimes even larger than the
 uncertainty induced by the current experimental accuracy of $\alpha_s(M_Z)$.
 </hidden>
|**R. Harlander, L. Mihaila, M. Steinhauser**  | 
|**  Phys. Rev. D   72 095009 2005  **  |
| {{preprints:2005:ttp05-14.pdf|PDF}} {{preprints:2005:ttp05-14.ps|PostScript}} [[http://arxiv.org/abs/hep-ph/0509048|arXiv]]   |
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