1 / 26

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

hafwen
Download Presentation

Charmless Two -Body B Decays Involving a Tensor Meson

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  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

More Related