CP asymmetries in three-body B± decays to charged pions and kaons

CP asymmetries have been measured recently by the LHCb collaboration in three-body B+ decays to final states involving charged pions and kaons. Large asymmetries with opposite signs at a level of about 60% have been observed in B-+/- -> pi(+/-)(or K-+/-)pi(+)pi(-) and B-+/- -> pi(K+K-)-K-+/- for restricted regions in the Dalitz plots involving pi(+)pi(-) and K+K- with low invariant mass. U-spin is shown to predict corresponding Delta S = 0 and Delta S = 1 asymmetries with opposite signs and inversely proportional to their branching ratios, in analogy with a successful relation predicted thirteen years ago between asymmetries in B-s -> K-pi(+) and B-0 -> K+pi(-). We compare these predictions with the measured integrated asymmetries. Effects of specific resonant or non-resonant partial waves on enhanced asymmetries for low-pair-mass regions of the Dalitz plot are studied in B-+/- -> pi(+/-)pi(+/-)pi(-). The closure of low-mass pi(+)pi(-) and K+K- channels involving only pi pi <-> K (K) over bar rescattering may explain by CPT approximately equal magnitudes and opposite signs measured in B-+/- -> pi(+/-)pi(+/-)pi(-) and B-+/- -> pi(K+K-)-K-+/-. (C) 2013 Elsevier B.V. All rights reserved.