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QCD Corrections to t anti-b H^- Associated Production in e^+ e^- Annihilation

Bernd A. Kniehl·Fantina Madricardo·Matthias Steinhauser
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Abstract

We calculate the QCD corrections to the cross section of e^+ e^- -> t anti-b H^- and its charge-conjugate counterpart within the minimal supersymmetric extension of the Standard Model. This process is particularly important if m_t < m_H + m_b and root(s) < 2 m_H, so that t -> b H^+ and e^+ e^- -> H^+ H^- are not allowed kinematically. Large logarithmic corrections that arise in the on-mass-shell scheme of quark mass renormalization, especially from the t anti-b H^- Yukawa coupling for large values of tan(beta), are resummed by adopting the modified minimal-subtraction scheme, so that the convergence behavior of the perturbative expansion is improved. The inclusion of the QCD corrections leads to a significant reduction of the theoretical uncertainties due to scheme and scale dependences.

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Bernd A. Kniehl, Fantina Madricardo, Matthias Steinhauser. 2002-07-12. QCD Corrections to t anti-b H^- Associated Production in e^+ e^- Annihilation. https://doi.org/10.1103/physrevd.66.054016

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