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Bs mixing observables and |Vtd/Vts| from sum rules

King, Daniel; Lenz, Alexander; Rauh, Thomas

Bs mixing observables and |Vtd/Vts| from sum rules Thumbnail


Daniel King

Alexander Lenz

Thomas Rauh


We consider the effects of a non-vanishing strange-quark mass in the determination of the full basis of dimension six matrix elements for Bs mixing, in particular we get for the ratio of the V − A Bag parameter in the Bs and Bd system: B s Q1 /B d Q1 = 0.987+0.007 −0.009. Combining these results with the most recent lattice values for the ratio of decay constants fBs /fBd we obtain the most precise determination of the ratio ξ = fBs q B s Q1 /fBd q B d Q1 = 1.2014+0.0065 −0.0072 in agreement with recent lattice determinations. We find ∆Ms = (18.5 +1.2 −1.5 )ps−1 and ∆Md = (0.547+0.035 −0.046)ps−1 to be consistent with experiments at below one sigma. Assuming the validity of the SM, our calculation can be used to directly determine the ratio of CKM elements |Vtd/Vts| = 0.2045+0.0012 −0.0013, which is compatible with the results from the CKM fitting groups, but again more precise.


King, D., Lenz, A., & Rauh, T. (2019). Bs mixing observables and |Vtd/Vts| from sum rules. Journal of High Energy Physics, 2019(5), Article 34.

Journal Article Type Article
Acceptance Date May 26, 2019
Online Publication Date May 30, 2019
Publication Date May 31, 2019
Deposit Date May 29, 2019
Publicly Available Date May 29, 2019
Journal Journal of High Energy Physics
Print ISSN 1126-6708
Publisher Scuola Internazionale Superiore di Studi Avanzati (SISSA)
Peer Reviewed Peer Reviewed
Volume 2019
Issue 5
Article Number 34


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Copyright Statement
This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

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