Eur. Phys. J. C (2011) 71: 1725
https://doi.org/10.1140/epjc/s10052-011-1725-z

Regular Article - Theoretical Physics

U(2) and minimal flavour violation in supersymmetry

¹ Scuola Normale Superiore and INFN, Piazza dei Cavalieri 7, 56126, Pisa, Italy
² Laboratori Nazionali di Frascati, INFN, Via E. Fermi 40, 00044, Frascati, Italy

^* e-mail: gino.isidori@lnf.infn.it

Received: 24 May 2011
Revised: 15 July 2011
Published online: 18 August 2011

Abstract

Rather than sticking to the full U(3)³ approximate symmetry normally invoked in Minimal Flavour Violation, we analyze the consequences on the current flavour data of a suitably broken U(2)³ symmetry acting on the first two generations of quarks and squarks. A definite correlation emerges between the ΔF=2 amplitudes , and , which can resolve the current tension between and , while predicting . In particular, the CP violating asymmetry in B _s →ψφ is predicted to be positive S _ψφ =0.12±0.05 and above its Standard Model value (S _ψφ =0.041±0.002). The preferred region for the gluino and the left-handed sbottom masses is below about 1÷1.5 TeV. An existence proof of a dynamical model realizing the U(2)³ picture is outlined.