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arXiv · 0907.2461

Effects of right-handed charged currents on the determinations of |V_ub| and |V_cb|

Andreas Crivellin
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Abstract

We study the effect of a right-handed coupling of quarks to the W-boson on the measurements of |V_ub| and |V_cb|. It is shown that such a coupling can remove the discrepancies between the determinations of |V_ub| from B\toπ\ellν, B^+\toτ^+ νand B\to X_u\ellν. Further the measurements of |V_cb| from B\to D^*\ellν, B\to D\ellνand inclusive B\to X_c\ellνdecays can be brought into better agreement. We demonstrate that a right-handed coupling can be generated within the MSSM by a finite gluino-squark loop. The effect involves the parameters δ^{u RL}_{23} and δ^{u RL}_{13} of the squark mass matrices, which are poorly constrained from other processes. On the other hand, all gluino-squark corrections to the regular left-handed coupling of the W-boson are found to be too small to be relevant.

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Andreas Crivellin. 2010-02-10. Effects of right-handed charged currents on the determinations of |V_ub| and |V_cb|. https://doi.org/10.1103/physrevd.81.031301

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