Institution: | a INFN, Sezione di Napoli and Dipartimento di Scienze Fisiche, Università di Napoli, I-80126 Napoli, Italy b Theory Division, CERN, CH-1211 Geneva 23, Switzerland c INFN, Laboratori Nazionali di Frascati, I-00044 Frascati, Italy |
Abstract: | Motivated by the new experimental information reported by the BNL-E787 Collaboration, we analyse the present impact and the future prospects opened by the measurement of
. Although still affected by a large error, the BNL-E787 result favours values of
substantially larger than what expected within the Standard Model. As a result, this data already provide non-trivial constraints on the unitarity triangle, when interpreted within the Standard Model framework. We stress the importance of the clean relation between
, sin2β and ΔMBd/ΔMBs that in the next few years could provide one of the deepest probes of the Standard Model in the sector of quark-flavour dynamics. A speculative discussion about possible non-standard interpretations of a large
is also presented. Two main scenarios naturally emerge: those with direct new-physics contributions to the
amplitude and those with direct new-physics effects only in Bd–
mixing. Realistic models originating these two scenarios and possible future strategies to clearly identify them are briefly discussed. |