Eur. Phys. J. C (2006) 48: 413-426
https://doi.org/10.1140/epjc/s10052-006-0034-4

Theoretical Physics

Probing new physics through B mixing: Status, benchmarks and prospects

¹ IPPP, Department of Physics, University of Durham, Durham, DH1 3LE, UK
² Theory Division, Department of Physics, CERN, 1211, Geneva 23, Switzerland

^* e-mail: patricia.ball@durham.ac.uk

Received: 19 July 2006
Published online: 19 October 2006

Abstract

As is well known, B⁰ _d,s–B̄⁰ _d,s mixing offers a profound probe into the effects of physics beyond the standard model. The data obtained at the e⁺e^- B factories have already provided valuable insights into the B_d-meson system, and very recently also the B⁰ _s–B̄⁰ _s oscillation frequency ΔM_s has been measured at the Tevatron. We give a critical discussion of the interpretation of these data in terms of model-independent new-physics parameters. We address in particular the impact of the uncertainties of the relevant input parameters, set benchmarks for their accuracies as required by future precision measurements at the LHC, and explore the prospects for new CP-violating effects in the B_s system. To complement our model-independent analysis, we also discuss the constraints imposed by the CDF measurement of ΔM_s on popular models of new physics, namely scenarios with an extra Z’ boson and supersymmetry. We find that the new data still leave sizeable room for new-physics contributions to B⁰ _s–B̄⁰ _s mixing, which could be detected at the LHC.