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Charmless Two -Body B Decays Involving a Tensor Meson

Charmless Two -Body B Decays Involving a Tensor Meson . Kwei -Chou Yang Chung-Yuan Christian University, Taiwan. T he 36th International Conference on High Energy Physics (ICHEP2012) . in collaboration with Hai -Yang Cheng. Outline. Polarization puzzles in

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Charmless Two -Body B Decays Involving a Tensor Meson

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  1. Charmless Two-Body B Decays Involving a Tensor Meson Kwei-Chou Yang Chung-Yuan Christian University, Taiwan The 36th International Conference on High Energy Physics (ICHEP2012) in collaboration with Hai-Yang Cheng

  2. Outline • Polarization puzzles in • ---- SM or New-Physics • B decays involving a tensor meson • ----further test: SM or New-Physics • Conclusion

  3. Introduction • Polarization puzzle in charmless B→VV decays In transversity basis Why is fT sizable ~ 0.5 in B→ K* φ decays ? • Search of new physics in B→VV decays ?

  4. Explanation within the SM: Annihilation In SM, the Annihilation effect is important: Parametrization

  5. B→ K*f (without annihilation) a3=a3+a5, a4=a4-rcfa6, a3,EW=a9+a7, b3= penguin ann h=0 h= - h=0 h= - Coefficients are helicity dependent ! PRD,2008, Hai-Yang Cheng, KCY with b3=0 constructive (destructive) interference in A- (A0) ⇒ fL~ 0.58 NLO corrections alone will bring down fL significantly ! Br ~4.3*10-6 (without annihilation), too small compared with data

  6. Although fL is reduced to 60% level, polarization puzzle is not resolved as the predicted rate, BR~ 4.3*10-6, is too small compared to the data, ~ 10*10-6 for B →K*f penguin annihilation f|| ≒ f⊥ ≒ 0.25

  7. constructive destructive with b3=0 destructive constructive ⇒ fL(K*-r0)=0.96, fL(K*0r0)=0.47 (=0.91 if aih are helicityindep) Without Annihilation But, the predicted rates for K*-r0 & K*0r0 are too small !

  8. Process dependent

  9. Tree-dominated VV modes • Longitudinal amplitude dominates tree-dominated decays • except for r0w • Predicted B→rr,ωr rates agree with the data. H.Y. Cheng & KCY, PRD, 2008 vs. data (2010)

  10. Scenario with New Physics

  11. Possible New Physics Phys. Rev. D71, 094002 (2005), KCY& Das See also works by Alex Kagan; C.S. Kim, Y.D. Yang;

  12. Two-body B decays involving a tensor meson

  13. Light-cone distribution amplitudes for a tensor meson chiral-even chiral-odd twist-2: ∥, twist-3: gv, ga, ht, hstwist-4: g3, h3 Asymptotic form of chiral-even DAs is first studied by Braun & Kivel (‘01) PRD82:054019,2010, H.Y. Cheng,Y. Koike, KCY

  14. 3P2 tensor meson Due to G-parity, , h∥(t), h∥(p), ∥,g(v), g(a) are antisymmetric with the replacement u→1-u in SU(3) limit Ci3/2: Gegenbauer polynomial twist-2: ∥, twist-3: g(v),g(a), h(t), h∥(p) related to twist-2 ones via Wandzura-Wilczek relations (neglecting 3-parton distributions)

  15. Decay constants • Tensor meson cannot be produced from local V-A current owing • to p=0 • Can be created from local current involving covariant derivatives • with Normalized with Previous estimates: Aliev & Shifman (’82); Aliev, Azizi, Bashiry (’10) Based on QCD sum rules we obtain (Cheng, Koike, KCY, arXiv:1007.3526)

  16. VT modes Data from BaBar Naïve factorization, Kim,Lee & Oh, PRD (2003); Munoz,Quintero, J.Phys.G (2009) QCD factorization (without annihilation) too small Within SM, to account for data, penguin annihilation is necessary PRD83:034001,2011, Hai-Yang Cheng, KCY

  17. Ann is dominant for To account for data, penguin annihilation is necessary 18 Process-dependent ?

  18. Polarization puzzle in B  K2* fL(K2*+) = 0.560.11, fL(K2*0) = 0.450.12, fL(K2*+) = 0.800.10, fL(K2*0) = 0.901+0.059-0.069 BaBar Why is fT/ fL <<1 for B K2* and fT /fL 1 for B K2* ? Why is that fT behaves differently in K2* and K* ? In QCDF, fL is very sensitive to the phase ATV for B K2*, but not so sensitive to AVT for B K2* fL(K2*) = 0.88, 0.72, 0.48 for ATV = -30o, -45o, -60o, fL(K2*)= 0.68, 0.66, 0.64 for AVT = -30o, -45o, -60o Rates & polarization fractions can be accommodated in QCDF but no dynamical explanation is offered Fine-tuning!

  19. Further test Sizable BR

  20. New Physics due to tensor currents B  K2* Relatively smaller Larger fL compared with K* B  K*

  21. Conclusions   New physics solutions: the only candidates are the tensor operators (Pure (S ± P)(S ± P) operators are unlikely) Further information(b→sss) can be extracted from  and some other modes involving the tensor meson

  22. (pseudo-)scalar-type operators tensor-type operators

  23. Can only (pseudo-)scalar-type operators explain the data? Answer: NO In theminimal supersymmetric standard model (MSSM), such scalar/pseudoscalar operators can be induced bythe penguin diagrams of neutral-Higgs bosons. A combined analysis of the decays and to be consistent with the data for shows that the NP effects only due to (pseudo-)scalar-type operators is much smaller in B →K*f modes. PRD77, 035013 (2008), H. Hatanaka, KCY

  24. Penguin-dominated B TP

  25. B-K2*0- vanishes in naïve factorization, while its BR is measured to be ~ 5.610-6  importance of nonfactorizble effects • Penguin annihilation is needed in QCDF to account for rates & CP asymmetries ATP=0.83, ATP = -70o APT=0.75, APT = -30o similar to the parameters for B PP

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