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arXiv · hep-ph/0305250

Improved full one--loop corrections to A^0 -> \sq_1 \sq_2 and \sq_2 -> \sq_1 A^0

Abstract

We calculate the full electroweak one-loop corrections to the decay of the CP-odd Higgs boson A^0 into scalar quarks in the minimal supersymmetric extension of the Standard Model (MSSM). Due to the complex structure of the electroweak sector a proper renormalization of many parameters in the on-shell renormalization scheme is necessary. For the decay into sbottom quarks, especially for large tanb, the corrections can be very large in the on-shell renormalization scheme, which makes the perturbation series unreliable. We solve this problem by an appropriate definition of the tree-level coupling in terms of running quark masses and running trilinear couplings A_q. We also discuss the decay of heavy scalar quarks into light scalar quarks and A^0. We find that the corrections are significant and therefore cannot be neglected.

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BibTeXRIS

C. Weber, H. Eberl, W. Majerotto. 2003-08-04. Improved full one--loop corrections to A^0 -> \sq_1 \sq_2 and \sq_2 -> \sq_1 A^0. https://doi.org/10.1016/j.physletb.2003.07.083

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