Accepted Friday Nov 06, 2009
We describe a novel use of the Dalitz plot to probe symmetry in three-body modes of B and D mesons. It is based on an observable inspired by astronomers' practice, namely the significance in the difference between corresponding Dalitz plot bins. It provides a model independent mapping of local asymmetries. We illustrate the method for probing symmetry in the two complementary cases of B and D decays: in the former sizable or even large effects can be expected, yet have to be differentiated against leading Standard Model contributions, while in the latter one cannot count on sizable effects, yet has to deal with much less Standard Model background.