%0 Journal Article %1 Collaboration2007Improved %A Collaboration, UTfit %A Bona, M. %A Ciuchini, M. %A Franco, E. %A Lubicz, V. %A Martinelli, G. %A Parodi, F. %A Pierini, M. %A Roudeau, P. %A Schiavi, C. %A Silvestrini, L. %A Sordini, V. %A Stocchi, A. %A Vagnoni, V. %D 2007 %K ckm %R 10.1103/physrevd.76.014015 %T Improved Determination of the CKM Angle alpha from B to pi pi decays %U http://dx.doi.org/10.1103/physrevd.76.014015 %X Motivated by a recent paper that compares the results of the analysis of the CKM angle alpha in the frequentist and in the Bayesian approaches, we have reconsidered the information on the hadronic amplitudes, which helps constraining the value of alpha in the Standard Model. We find that the Bayesian method gives consistent results irrespective of the parametrisation of the hadronic amplitudes and that the results of the frequentist and Bayesian approaches are equivalent when comparing meaningful probability ranges or confidence levels. We also find that from B to pi pi decays alone the 95\% probability region for alpha is the interval 80^o,170^o, well consistent with recent analyses of the unitarity triangle where, by using all the available experimental and theoretical information, one gets alpha = (93 +- 4)^o. Last but not least, by using simple arguments on the hadronic matrix elements, we show that the unphysical region alpha \~ 0, present in several experimental analyses, can be eliminated.

@article{Collaboration2007Improved, abstract = {{Motivated by a recent paper that compares the results of the analysis of the CKM angle alpha in the frequentist and in the Bayesian approaches, we have reconsidered the information on the hadronic amplitudes, which helps constraining the value of alpha in the Standard Model. We find that the Bayesian method gives consistent results irrespective of the parametrisation of the hadronic amplitudes and that the results of the frequentist and Bayesian approaches are equivalent when comparing meaningful probability ranges or confidence levels. We also find that from B to pi pi decays alone the 95\% probability region for alpha is the interval [80^o,170^o], well consistent with recent analyses of the unitarity triangle where, by using all the available experimental and theoretical information, one gets alpha = (93 +- 4)^o. Last but not least, by using simple arguments on the hadronic matrix elements, we show that the unphysical region alpha \~{} 0, present in several experimental analyses, can be eliminated.}}, added-at = {2019-02-23T22:09:48.000+0100}, archiveprefix = {arXiv}, author = {Collaboration, UTfit and Bona, M. and Ciuchini, M. and Franco, E. and Lubicz, V. and Martinelli, G. and Parodi, F. and Pierini, M. and Roudeau, P. and Schiavi, C. and Silvestrini, L. and Sordini, V. and Stocchi, A. and Vagnoni, V.}, biburl = {https://www.bibsonomy.org/bibtex/23df6224cece8f2ea423293c4489fdef2/cmcneile}, citeulike-article-id = {6945600}, citeulike-linkout-0 = {http://arxiv.org/abs/hep-ph/0701204}, citeulike-linkout-1 = {http://arxiv.org/pdf/hep-ph/0701204}, citeulike-linkout-2 = {http://dx.doi.org/10.1103/physrevd.76.014015}, day = 24, doi = {10.1103/physrevd.76.014015}, eprint = {hep-ph/0701204}, interhash = {b579f9f8b0d1925a94f7c99aab8964c5}, intrahash = {3df6224cece8f2ea423293c4489fdef2}, keywords = {ckm}, month = jan, posted-at = {2010-04-03 12:36:45}, priority = {2}, timestamp = {2019-02-23T22:15:27.000+0100}, title = {{Improved Determination of the CKM Angle alpha from B to pi pi decays}}, url = {http://dx.doi.org/10.1103/physrevd.76.014015}, year = 2007 }