Standard model predictions and new physics sensitivity inB→DDdecays

Abstract

An extensive model-independent analysis of B → DD decays is carried out employing SU(3) flavour symmetry, including symmetry-breaking corrections. Several theoretically clean observables are identified which allow for testing the Standard Model. These include the known time-dependent CP asymmetries, the penguin pollution of which can be controlled in this framework, but notably also quasi-isospin relations which are experimentally well accessible and unaffected by symmetrybreaking corrections. Theoretical assumptions can be kept to a minimum and controlled by additional sum rules. Available data are used in global fits to predict the branching ratio for thes decay as well as several CP asymmetries which have not been measured so far, and future prospects are analyzed.

SU(3)F analysis for beauty baryon decays

“…See also Refs. [52] and [53] for the application of these Hamiltonians to B → J/ψK and B → DD, respectively. The notation for the subindices are such that (N) I,I 3 ,Y refers to the irreducible representation N of SU(3) F using the quantum numbers of strong isospin I, I 3 and strong hypercharge Y .…”

Theory overview

“…To make nevertheless theoretical statements, assumptions like SU(3) F -symmetry are regularly used in the literature, see e.g. [68,69,70,71,72,73,74] for some recent (2013 onward) references. In the long term future this problem might be solvable with lattice QCD, by an extension [75] of methods that have shown to be very successful for hadronic Kaon decays [51].…”

LHCb results on CP violation in B0_{d/s} mixing and in the interference with decays

“…Measuring the CP violation in B 0 → D + D − decays is motivated by more than obtaining an effective sin 2β eff B→DD measurement [11,12,13]. The measurement of the phase shift ∆φ serves…”