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 2 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.
%0 Journal Article
%1 Lunghi2009Unitarity
%A Lunghi, E.
%A Soni, A.
%D 2009
%K flavour
%T Unitarity Triangle Without Semileptonic Decays
%U http://arxiv.org/abs/0912.0002
%X 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 2 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.
@article{Lunghi2009Unitarity,
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 2 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.}},
added-at = {2019-02-23T22:09:48.000+0100},
archiveprefix = {arXiv},
author = {Lunghi, E. and Soni, A.},
biburl = {https://www.bibsonomy.org/bibtex/2765e8b2ed1f94df97b127d69490a12eb/cmcneile},
citeulike-article-id = {6283576},
citeulike-linkout-0 = {http://arxiv.org/abs/0912.0002},
citeulike-linkout-1 = {http://arxiv.org/pdf/0912.0002},
comment = {(private-note)Good motivation for improving f\_B and f\_Bs},
day = 30,
eprint = {0912.0002},
interhash = {9fb1ffe8ec2ba57459172997dc421fef},
intrahash = {765e8b2ed1f94df97b127d69490a12eb},
keywords = {flavour},
month = nov,
posted-at = {2009-12-02 11:00:16},
priority = {0},
timestamp = {2019-02-23T22:15:27.000+0100},
title = {{Unitarity Triangle Without Semileptonic Decays}},
url = {http://arxiv.org/abs/0912.0002},
year = 2009
}