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Using B  D (s) (*) D (*) to constrain g

Using B  D (s) (*) D (*) to constrain g. The CP asymmetry from the D (*) D (*) tree amplitude. measures sin2  , so where does  come in?   comes from the u- and t- penguin terms:.

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Using B  D (s) (*) D (*) to constrain g

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  1. Using B  D(s)(*)D(*) to constrain g • The CP asymmetry from the D(*)D(*) tree amplitude measures sin2, so where does  come in?   comes from the u- and t-penguin terms: • For a given B D(*)D(*)decay, there are 3 observables: a branching fraction, a direct CP asymmetry, and a time-dependent CP asymmetry (3 of each – one for each helicity state – in the case of D*+D*-):

  2. How can D(s)(*)D(*)decays measure gamma? • This is 3 equations in 5 unknowns. More information required… • The additional information can be obtained by inputting two things: 1) beta, as determined from charmonium decays, and 2) branching fractions of B Ds(*)D(*)decays. • SU(3)-breaking in the relation between D(*)D(*)and Ds(*)D(*)is parameterized by the ratio of decay constants = fDs(*)/fD(*)  fDs/fD = 1.22 ± 0.04(lattice QCD, Becirovic et al. 2003). • Thus, the 3 equations in 3 unknowns can be solved into a single equation for : solution for  (in V-V and P-P modes) where:

  3. New Branching Fractions and ACP Values = newly discovered B decay modes = first measurements hep-ex/0604037, submitted to PRD

  4. Constraints on gamma from D(s)(*)D(*)

  5. Hints of new physics? Anomalies in charmless decays with loops: Low value of longitudinally-polarized fraction in K*. Unexpectedly low values of CP asymmetries. Potential signs of new physics in loops…?

  6. How can we tell if the SM is in trouble? • SU(3) relations can be used to establish the maximum deviation one would expect from purely standard model effects. • Separation of SM effects from new physics ones, eg. hep-ph/0303171: • Relations such as establish the maximum departure in terms of BFs of related modes.

  7. Decays related to K* by SU(3) • B0  00 • B0   • B0  0 • B0  0 • B0   • B0    recent Babar limits: x 10-6 Old CLEO limit (13 x 10-6) Never been measured!

  8. New B0  &  Results Log Likelihood vs. BF ωωpolarization vs. BF B(B0  ) < 1.2 x 10-6at 90% C.L. B(B0  ) = 1.8-0.9 x 10-6 (< 4.0 x 10-6at 90% C.L.) Central value of  is larger than expected … Source same as transverse K* …??  hep-ex/060517, results presented at ICHEP06 and accepted for publication (PRD Rapid Communications). +1.3

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