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Unitarity Triangle Without Semileptonic Decays

High Energy Physics - Phenomenology 2014-11-20 v2 High Energy Physics - Experiment High Energy Physics - Lattice

Abstract

Use of semi-leptonic decays has become standard in constraining the Unitarity Triangle. Bearing in mind that precise calculations of these are very challenging, we propose an entirely new approach. In particular the |Vcb| + epsilon_K constraint, which depends extremely sensitively on Vcb in the traditional method, is replaced by the interplay between epsilon_K, BR(B ->tau nu) and Delta M_Bs. It is found that even in this method tensions with the Standard Model persist at the ~1.8 sigma level. Furthermore, improvements on the B -> tau nu branching ratio and on the lattice determination of f_Bs Bs^(1/2) can increase the effectiveness of this method significantly.

Keywords

Cite

@article{arxiv.0912.0002,
  title  = {Unitarity Triangle Without Semileptonic Decays},
  author = {E. Lunghi and A. Soni},
  journal= {arXiv preprint arXiv:0912.0002},
  year   = {2014}
}

Comments

6 pages, 5 figures, Inputs and numerics updated, References added, Conclusions unchanged

R2 v1 2026-06-21T14:17:53.515Z