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arXiv · hep-ph/9505304

Precision tests of the MSSM

P. H. Chankowski·S. Pokorski
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Abstract

We present the results of a first global fit to the electroweak observables in the MSSM. The best fit selects either very low or very large values of ~$\tanβ$ ~and, correspondingly, chargino (higgsino--like) and stop or the ~$CP-$odd Higgs boson are within the reach of LEP 2. Moreover, the best fit gives ~ $α_s(M_Z)=0.118^{+0.005}_{-0.010}$, ~which is lower than the one obtained from the SM fits. The overall fit is excellent ~ ($χ^2=7.2$ ~for 15 d.o.f. as compared to ~$χ^2=11$ ~in the SM). Those results follow from the fact that in the MSSM one can increase the value of ~ $R_b\equivΓ_{Z^0\to\bar bb}/Γ_{Z^0\to hadrons}$ ~ {\it without} modyfying the SM predictions for other observables.

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P. H. Chankowski, S. Pokorski. 1995-05-15. Precision tests of the MSSM. https://doi.org/10.1016/0370-2693(95)01337-7

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