Large direct CP violation in B → φφXs decays

We present a novel method to search for a new CP-violating phase in the b --> s (s) over bars (s) over bars transition rising B --> phiphiX(s) decays, where X-s represents a final state with a specific strange flavor such as K+/-, K*(+/-) or K+/-T-/+. Direct CP violation can be enhanced due to an interference between an amplitude beyond the standard model (SM) and the SM decay amplitude through the eta(c) resonance. We find that the CP asymmetry can be as large as 0.4 within the present experimental bounds on the b --> s (s) over bars transition. These decays provide a very clean experimental signature and the background is expected to be small in particular at e(+)e(-) B factories. A simulation study for the B+/- --> phiphiK(+/-) decay shows that the statistical significance of CP violation can exceed 5 standard deviations with 10(9) B mesons. (C) 2004 Published by Elsevier B.V.