Article ID Journal Published Year Pages File Type
1846878 Nuclear Physics B - Proceedings Supplements 2008 6 Pages PDF
Abstract

We review the theoretical status of the lifetime ratios τB+/τBd, τBs/τBd, τΛb/τBd and τBc and of the mixing quantities ΔMs, ΔΓs and ϕs. ΔMs and ΔΓs suffer from large uncertainties due to the badly known decay constants, while the ratio ΔΓs/ΔMs can be determined with almost no non-perturbative uncertainties, therefore it can be used perfectly to find possible new physics contributions in the mixing parameters. We suggest a very clear method of visualizing the bounds on new physics and demonstrate this by combining the latest experimental numbers on the mixing quantities quantities with theory – one already gets some hints for new physics contributions, but more precise experimental numbers are needed to draw some definite conclusions. We conclude with a ranking list of all the discussed quantities according to their current theoretical uncertainties and point out possible improvements.

Related Topics
Physical Sciences and Engineering Physics and Astronomy Nuclear and High Energy Physics