Search for Super-Penguins: CP Violation in B0->K+K-K0 D. Dujmic, SLAC For BABAR Collaboration SM rules Special thanks to: G. Cavoto, M. Krishnamurthy, E. Di Marco, M.Pierini, A.Roodman, S.Spanier, J.Thompson Sep 11, 2006 SLUO Anual Meeting 2006

CP Violation in SM ? CKM picture of charged weak currents: p=u,c,t W ± (solely responsible for CPV in SM) p=u,c,t q=d’,s’,b’ W ± Vpq ? But amount of CP violation too small: - observation: - area of unitarity triangle: Additional sources of CP violation needed Sep 11, 2006 SLUO Anual Meeting 2006

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 Sep 11, 2006 SLUO Anual Meeting 2006

CPV Parameter sin2b  B0  K+K-K0 amplitudes: CPAsymmetry: IF: flavor K+K-K0 B0  K+K-K0 amplitudes: tag 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 ~0 same asymmetry for J/YKS and K+K-KS IF: or super-penguins exist! Sep 11, 2006 SLUO Anual Meeting 2006

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) Sep 11, 2006 SLUO Anual Meeting 2006

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 both CP-even and CP-odd * K+ K- B0 KS L L’=L L=even CP(K+K-KS)= +1 -sin2b L=odd CP(K+K-KS) = -1 +sin2b Dilution if both CP present!! -> (2fodd-1) sin2b How to analyze angular momentum composition? *[ CP(KKKS)= - CP(KKKL) ] Sep 11, 2006 SLUO Anual Meeting 2006

Need Dalitz plot analysis to measure CP asymmetry 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 previously: - cut >1.1GeV (assume CP-even) - 1.0045<m<1.0345 (assume CP-odd) Need Dalitz plot analysis to measure CP asymmetry Sep 11, 2006 SLUO Anual Meeting 2006

B0→K+K-K0 Isobar Model fK0 f0(980)K0 X0(1550)K0 Non-resonant Component CP fK0 odd f0(980)K0 even X0(1550)K0 Nonresonant even(90%) odd(10%) cc0K0 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 Sep 11, 2006 SLUO Anual Meeting 2006

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 Sep 11, 2006 SLUO Anual Meeting 2006

… 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 Sep 11, 2006 SLUO Anual Meeting 2006

Average CP-Asymmetry Combine KKKS+-, KKKS00, and KKKL KKKS+- alone: Assume same CPV parameters for all KKK0 KKKS+- alone: SM: ACP=0 b=0.370 Component Fraction (%) fK0 12.9±1.3 f0(980)K0 22.3±8.9 X0(1550)K0 4.1±1.8 Nonresonant 91±19 cc0K0 2.8±0.8 D-K+, DS-K+ 4.9±1.1 Sep 11, 2006 SLUO Anual Meeting 2006

Measurement of b 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 Sep 11, 2006 SLUO Anual Meeting 2006

CPV in Low K+K- Mass Resonant fractions for m(K+K-)<1.1GeV f(1020)K0 57% f0(980)K0 34% Non-res 13% 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 KKKs+- 252 ± 19 KKKs00 35 ± 9 KKKL 195 ± 33 Sep 11, 2006 SLUO Anual Meeting 2006

CPV in Low K+K- Mass Combined KKKS+-, KKKS00, and KKKL fKS ACP=0 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 Sep 11, 2006 SLUO Anual Meeting 2006

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 BABAR (bsin2b) Belle (sin2b) KKK0 0.661 ±0.12 ± 0.06 (all KKK0) 0.68 ±0.15 ±0.03 +0.21 −0.13 (excluding fKS, KKKS only) fK0 0.12 ±0.31 ±0.10 0.50 ±0.21 ±0.06 f0(KK)K0 0.31± 0.32 ± 0.07 No result (f0K+K-) 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 Sep 11, 2006 SLUO Anual Meeting 2006

More Slides Sep 11, 2006 SLUO Anual Meeting 2006

Angular Moments K+ KS K- - 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: S-wave - Moments <PL> computed using sPlots [Pivk, Le Diberder, Nucl.Inst.Meth. A555] - Fraction of P-wave: P-wave (angular momentum conservation) Sep 11, 2006 SLUO Anual Meeting 2006

BABAR/Belle 2006: B0  KKKS Belle BABAR Belle’s estimate (±10MeV): Belle’s helicity plot (±10MeV under f mass) [Hazumi ICHEP06 talk] 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 Sep 11, 2006 SLUO Anual Meeting 2006

Dalitz Plot Isobar Model “Non-resonant” i j k “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 Sep 11, 2006 SLUO Anual Meeting 2006