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Search for Super-Penguins: CP Violation in B 0 ->K+K-K 0

Search for Super-Penguins: CP Violation in B 0 ->K+K-K 0. SM rules. D. Dujmic, SLAC For BABAR Collaboration. Special thanks to: G. Cavoto, M. Krishnamurthy, E. Di Marco, M.Pierini, A.Roodman, S.Spanier, J.Thompson. p=u,c,t. W ±. V pq. ?. q=d’,s’,b’. CP Violation in SM.

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Search for Super-Penguins: CP Violation in B 0 ->K+K-K 0

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  1. Search for Super-Penguins:CP Violation in B0->K+K-K0 SM rules D. Dujmic, SLAC For BABAR Collaboration Special thanks to: G. Cavoto, M. Krishnamurthy, E. Di Marco, M.Pierini, A.Roodman, S.Spanier, J.Thompson SLUO Anual Meeting 2006

  2. p=u,c,t W ± Vpq ? q=d’,s’,b’ CP Violation in SM CKM picture of charged weak currents: (solely responsible for CPV in SM) • But amount of CP violation too small: • - observation: • - area of unitarity triangle: Additional sources of CP violation needed SLUO Anual Meeting 2006

  3. Search for Super-Penguins • Penguin amplitude in SM • Super-penguin, beyond-SM? Example of SUSY diagram SM rules Double-CKM suppression: Loop suppression: Decay rates small BF<7·10-5 • Virtual, heavy particles can appear in loops • - can be relatively large, O(1) • - in general not CP-conserving SLUO Anual Meeting 2006

  4. ~0 CPV Parameter sin2b e+ flavor K+K-K0 tag B0  K+K-K0 amplitudes: e-  • Interference term has different signs for B0/B0bar tags • Interference phase only due to B0/B0bar mixing (in SM) SM CPAsymmetry: (B0/B0bar tags) super penguins same asymmetry for J/YKS and K+K-KS IF: super-penguins exist! or SLUO Anual Meeting 2006

  5. Estimate of Dsin2b in K+K-KS Tree From tree-dominated decays B0->J/yKS (SM reference point): Penguin Experimental average of all penguins (penguin-tree) SLUO Anual Meeting 2006

  6. K+ L’=L B0 KS L K- Analysis of 3-Body Decay • Selection of charm-less 3-body decays is tricky • - large background requires usage of several kinematic, event-shape variables in event selection • - good particle ID • CP Violation measurement with additional complication • - CP depends on angular momentum L between K+ and K- • - (K+ K-)KS can be bothCP-even and CP-odd * -sin2b CP(K+K-KS)= +1 L=even +sin2b CP(K+K-KS) = -1 L=odd Dilution if both CP present!! -> (2fodd-1) sin2b How to analyze angular momentum composition? *[ CP(KKKS)= - CP(KKKL) ] SLUO Anual Meeting 2006

  7. CP Content • Fractions of P-wave from analysis of angular moments: • 0.29 ± 0.03 over whole DP • 0.89 ± 0.01 in f(1020) region BABAR-CONF-06/40 (ICHEP06) P-wave strength Fraction of P-wave From 879±36 K+K-KS(p+p-) decays From 624±30 K+K+K- decays Need Dalitz plot analysis to measure CP asymmetry previously: - cut >1.1GeV (assume CP-even) - 1.0045<m<1.0345 (assume CP-odd) SLUO Anual Meeting 2006

  8. B0→K+K-K0Isobar Model toy Dalitz plot fK0 f0(980)K0 X0(1550)K0 Non-resonant Charm(onium) contributions: D-K+, DS-K+ cc0K0 Use flavor-symmetry to relate BABAR’s K+K+K- Dalitz plot SLUO Anual Meeting 2006

  9. Dalitz Plot PDF Measure CP asymmetry in time-dependent Dalitz plot: Five observables: Dt, s(Dt), m(K+K-), cosqH, tag flavor B0 amplitude B0bar amplitude CP Violation: Rate difference Phase difference SLUO Anual Meeting 2006

  10. … Add All K+K-K0 Final States K+K-KS(p+p-) 138 ± 17 K+K-KS(p0p0) f(1020) 879 ± 36 “X0(1550)” Non-resonant cc0 f0(980) K+K-KL 499 ± 52 Add K+K-KS(KSp0p0) and K+K-KL All channels use same Dalitz plot model! ~1500 signal events SLUO Anual Meeting 2006

  11. Average CP-Asymmetry Combine KKKS+-, KKKS00, and KKKL Assume same CPV parameters for all KKK0 KKKS+- alone: SM: ACP=0 b=0.370 SLUO Anual Meeting 2006

  12. Measurement ofb • Assume final state is mixture of CP-eigenstates (partial waves) both real and imaginary b/c of CP-even, -odd interferences (->2b) real in Q2B analyses (->sin2b) p/2-beff p/2-beff beff 4.6s SLUO Anual Meeting 2006

  13. CPV in Low K+K- Mass • Resonant fractions for m(K+K-)<1.1GeV • Low-K+K- mass fit for CPV parameters in fK0 and f0K0 to reduce dependence on Dalitz plot model • fK0 theoretically very clean s(sin2b)~ O(1%) • Fix S-wave, float isobar parameters for P-wave SLUO Anual Meeting 2006

  14. CPV in Low K+K- Mass Combined KKKS+-, KKKS00, and KKKL asymmetry plot ±15MeV under f fKS SM: ACP=0 b=0.370 f0KS • CPV measurements in f0Ks and fKs correlated (one background for the other) • cross-check with Q2B analysis • syst. errors dominated by Dalitz plot model • consistent with SM, Belle SLUO Anual Meeting 2006

  15. Summary • Time-dependent Dalitz plot analysis opens new possibilities in study of penguin decays: • - measurement of asymmetry angle (instead of sine of the angle) • - removes dilution for final states with opposite CP • - model uncertainties included in fit • Lower sin2b than expected consistent with trend seen in other analyses • CPV results from penguin decays still intriguing, but need to work harder to observe new phenomena SLUO Anual Meeting 2006

  16. More Slides SLUO Anual Meeting 2006

  17. K+ S-wave KS K- P-wave Angular Moments - Model-independent approach to extract CP content [BABAR, PRD71,091102] - Assume S and P-waves decaying into K+K- K+K- CMS - Decay rate in terms of moments of Legendre polynomials: - Moments <PL> computed using sPlots [Pivk, Le Diberder, Nucl.Inst.Meth. A555] - Fraction of P-wave: (angular momentum conservation) SLUO Anual Meeting 2006

  18. Belle’s helicity plot (±10MeV under f mass) [Hazumi ICHEP06 talk] BABAR/Belle 2006: B0KKKS BABAR Belle B+K+K+K- (230MBB) PRD72,032003(2006) non-zero yield below and above f peak! B0K+K-K0 (347MBB) (bkg substracted) hep-ex/0607112 • Belle’s estimate (±10MeV): • K+K+K- Dalitz (140 fb-1) ~2.75±0.14% • ignores f0(980) • Estimates from BABAR results (±10MeV): • K+K+K- moments (347MBB): ~8±1% • K+K-K0 Dalitz (347MBB) and K+K+K- Dalitz (230MBB): f0K~10±3%, NR~3±1% -> 13±3% Belle’s fitting range Old BABAR fitting range SLUO Anual Meeting 2006

  19. i j k Dalitz Plot Isobar Model “Non-resonant” “resonant” i k Decay amplitude ∑res {ij}res  = B j B Resonant amplitude: Blatt-Weisskopf form factors Breit-Wigner Angular correlations Coupled channel BW (Flatté) Single channel BW SLUO Anual Meeting 2006

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