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arXiv · 0907.5376

Exact NLO strong interaction corrections to the Delta F=2 effective Hamiltonian in the MSSM

Javier Virto
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Abstract

We compute the order alpha_s^3 (next-to-leading) corrections to the Wilson coefficients of the Delta F=2 effective Hamiltonian in the Minimal Supersymmetric Standard Model with completely arbitrary soft terms. These results are relevant for phenomenological studies of neutral meson mixings in the presence of large squark mass splittings, in particular in hierarchical scenarios of supersymmetry. These corrections achieve a considerable reduction of the uncertainty related to the matching scale ambiguity, and are therefore numerically relevant. We briefly analyze the effect of certain mass splittings on the size of the NLO corrections, and compare it with the case of almost degenerate squarks in the mass insertion approximation.

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Javier Virto. 2009-07-30. Exact NLO strong interaction corrections to the Delta F=2 effective Hamiltonian in the MSSM. https://doi.org/10.1088/1126-6708/2009/11/055

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