Open Access Letter

First evidence of new physics in b s transitions

Marcella Bona1, Marco Ciuchini2, Enrico Franco3, Vittorio Lubicz24, Guido Martinelli35, Fabrizio Parodi6, Maurizio Pierini1, Carlo Schiavi6, Luca Silvestrini3*, Viola Sordini7, Achille Stocchi8 and Vincenzo Vagnoni9

Author Affiliations

1 CERN, CH-1211 Geneva 23, Switzerland

2 INFN, Sezione di Roma Tre, I-00146 Roma, Italy

3 INFN, Sezione di Roma, I-00185 Roma, Italy

4 Dipartimento di Fisica, Università di Roma Tre, I-00146 Roma, Italy

5 Dipartimento di Fisica, Università di Roma "La Sapienza", I-00185 Roma, Italy

6 Dipartimento di Fisica, Università di Genova and INFN, I-16146 Genova, Italy

7 ETH Zurich, HG Raemistrasse 101, 8092 Zurich, Switzerland

8 Laboratoire de l'Accélérateur Linéaire, IN2P3-CNRS et Université de Paris-Sud, BP 34, F-91898 Orsay Cedex, France

9 INFN, Sezione di Bologna, I-40126 Bologna, Italy

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PMC Physics A 2009, 3:6  doi:10.1186/1754-0410-3-6

Published: 18 December 2009


We combine all the available experimental information on Bs mixing, including the very recent tagged analyses of Bs Jϕ by the CDF and DØ collaborations. We find that the phase of the Bs mixing amplitude deviates more than 3σ from the Standard Model prediction. While no single measurement has a 3σ significance yet, all the constraints show a remarkable agreement with the combined result. This is a first evidence of physics beyond the Standard Model. This result disfavours New Physics models with Minimal Flavour Violation with the same significance.

PACS Codes: 12.15.Ff, 12.15.Hh, 14.40.Nb