CP violation in multibody B decays from QCD factorization

Abstract

We test a data-driven approach based on QCD factorization for charmless three-body B-decays by confronting it to measurements of CP violation in B − → π − π + π − . While some of the needed non-perturbative objects can be directly extracted from data, some others can, so far, only be modelled. Although this approach is currently model dependent, we comment on the perspectives to reduce this model dependence. While our model naturally accommodates the gross features of the Dalitz distribution, it cannot quantitatively explain the details seen in the current experimental data on local CP asymmetries. We comment on possible refinements of our simple model and conclude by briefly discussing a possible extension of the model to large invariant masses, where large local CP asymmetries have been measured.

Timelike-helicity B→ππ form factor from light-cone sum rules with dipion distribution amplitudes

“…[7] in terms of B-meson DAs, and complementary to the derivations from dispersion theory [10], and to the calculations at large k 2 [11]. The form factor F t obtained here, while not contributing to the semileptonic B → ππ ν rate in the massless lepton approximation, plays an important role in the factorization formula for nonleptonic B → πππ decays [12][13][14]. Further improvements of the sum rules presented here and in Refs.…”

B →P and B →V form factors from B-meson light-cone sum rules beyond leading twist

“…A dedicated programme has emerged in recent years to study ππ [10,[24][25][26][27][28][29] and Kπ [30][31][32][33] final states beyond a simple resonance ansatz. LCSR analyses of B → P 1 P 2 form factors require ongoing updates [34,35] by other authors to improve our understanding of the semileptonic processes as well as purely hadronic multi-body B decays [36][37][38][39][40][41][42].…”

Light-cone sum rules for B → K π form factors and applications to rare decays

“…While we will focus on the application to the semileptonic flavour-changing neutral-current decays, this is not the only case to which the results of this article apply. Analogously to nonleptonic decays of the type B → K * M where factorization in the heavy-quark limit reduces the amplitudes to simpler objects including B → K * form factors [28,29], the three body non-leptonic decays such as B → Kππ are also reducible to B → Kπ form factors in certain regions of phase space [30][31][32]. Thus the results in this are also needed to compute predictions for non-leptonic three-body decays.…”