1 / 27

Testing the SM with penguin-dominated B-decays

Testing the SM with penguin-dominated B-decays. Amarjit Soni HET,BNL (soni@bnl.gov). Outline. How good a null test is this? How well does the penguin-dominate? Possible dynamical enhancement of u-quark ? Why (LD)FSI has become a significant concern? How can we tackle this complication?

quasar
Télécharger la présentation

Testing the SM with penguin-dominated B-decays

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. Testing the SM with penguin-dominated B-decays Amarjit Soni HET,BNL (soni@bnl.gov)

  2. Outline • How good a null test is this? • How well does the penguin-dominate? • Possible dynamical enhancement of u-quark ? • Why (LD)FSI has become a significant concern? • How can we tackle this complication? • How well can we exploit correlation between ΔSf (=Sf – SψK ) and Cf ? • Can we make stronger statement about the sign of ΔSf ? • Are there (theoretically) problematic modes? • Averaging issue • Summary and Conclusions .

  3. Questions for the Super-B Workshop

  4. Brief Recapitulation: Basic Idea Dominant decay amp.has 0 weak phase [just as in B->ψKS] up to O(λ2)

  5. Brief remarks on the old study(with London, PLB’97) • Originally motivated by the thenCLEO discovery of • Huge inclusive (see Browder..) as well as exclusive • (see J. Smith…) Brs. into η’ • Suggest with Atwood(PLB97;PRL97) use of η’ Xs(d) • for search of NP via DIRCP as in SM expect very small • With London suggest use of MICP in [η’ , η ,π0,ρ0,ω,φ….]KS to test CKM-paradigm via sin2φ1(β) • Present simple (naïve) estimates of T/P …for • All cases T/P <0.04 • Due to obvious limitations of method suggest conservative • Bound ΔSf <0.10 for the SM For DIRCP see also Hou&Tseng, PRL’98

  6. J. Smith@CKM05 WA ~ 2.7σ

  7. Averaging issue:Are we makinga mountain outa anthill? • I am rather sceptical and concerned about averaging over many small deviations, leading to ~3.7 σ ….On the other hand, London&A.S, hep-ph/9704277

  8. Null Test(s) • In light of B-factory results (existing exptal info+lattice+phenomenology)-> deviations from CKM-paradigm due BSM-CP-odd phase(s) are likely to be small-> should develop Null Tests • Since CP is not an exact symmetry of SM->No EXACT NULL TESTS-> Need “Approximate Null Tests” (ANTs). • In b->s transitions, penguin-dominated B-decays are a powerful ANT • W(“worthiness”)=C(“cleanliness”) X S(“sensitivity”)=4.5* X 5* • ANT: In large class of modes such as (π0,ρ,ω,η’,φ,f0,K0K0…)K0 , (penguin/Total) ~ 1 -> ΔSf ~0 • Summary of early (London + AS, PLB’97) study…. • ΔSf < 0.1 in the SM (for modes discussed therein) • Summary of Recent Reaxmination (Cheng,Chua+AS,hepph/0502235….) , ΔSf > 0.1 most likely due BSM-CP-odd phase (for many modes)

  9. 10192

  10. A possible complications: large FSI phases in 2-body B decays • The original papers predicting ΔSf=Sf - SψK ~0 used naïve factorization ideas; in particular FSI were completely ignored. A remarkable discovery of the past year is that direct CP in charmless 2-body modes is very large-> (LD)FS phases in B-decays need not be small SINCE THESE ARE INHERENTLY Non-perturbative model dependence becomes unavoidable

  11. HYC-CKM05

  12. HYC-CKM05

  13. HYC-CKM05

  14. B  K All rescattering diagrams contribute to penguin topology, dominated by charm intermediate states fit to rates  rD = rD*  0.67  predict direct CPV Should reduce model dependence Significantly for CPV

  15. HYC-CKM05

  16. Cheng,Chua,A.S. Hep-ph/0502235 1.Note in SD, ΔS switches sign bet. ω,ρ for us no change 2. LD rescattering effects on S & C are highly correlated and similarly C’s of isospin partners are correlated -> many testable predictions,e.g LARGE (13%)DIR CP for ω KS & HUGE for ρ KS (~ -46%)

  17. _ _ _ _ • Only LD uncertainties due to form-factor cutoff are shown here. Total errors=SD+LD, for example, • FSI yields correct sign and magnitude for A(+K-) • P/T|SD=0.12 exp(-i177), P/TSD+LD=(0.140.01)exp[i(1478)]

  18. Note the very large (~ -40%) DCP in ρ0 K- & ρ0 K0

  19. More remarks & ρ0KS May be a good way Based on our study it seems difficult to accommodate ΔS>0.10 within the SM at least for KS[ή,φ]

  20. Summary (1 of 2) 1) Penguin dominated B-decays (b->s) are very useful “ANTs” of SM; for many modes ΔS>0.10 difficult to accommodate in SM. 2) The η’ KS is esp. clean…due dominance of Penguin (huge Br), which was in fact the original motivation for suggesting the η’ ; Model calculations show ΔS(η’ KS )~0.01. Since expt. Error for η’ KS is smallest (0.11), prospects for precision for this mode seem promising. 3) S-C correlation provides a very useful check On the models -> improved expt. measurements should lead to improvements in the models -> other modes may also become useful. 4) Noteable predictions of our model: large dir.CP in [ π,ρ] K- , [ρ,ω]KS 5) The sign of ΔS in our (and several other) model(s) tends to be positive with small central value (compared to largish ) errors; thus conclusive statements regarding the sign are difficult to make (Exptal. sign of ΔS tends to be negative!)

  21. Sign of ΔS in the SM Mode pQCD(SM ) QCDF(MB) QCDF+FSI(CCS) η’KS .01(.01,-.01) .00(.00,-.04) φKS ..020(.004,-.008) .02(.01,-.01) .03(.01,-.04) πKS .009(.001,-.003).07(.05,-.04) .04(.02,-.03)

  22. Summary (2):Bottomline Most of the effect currently is driven by the largish ΔS for η’ KS . If New Physics is responsible for this then NP MUST show up in numerous (b ->s) channels e.g. η’ K- , φ[K0,K-…](*), affecting mixing, dir and triple-corr CP…AND BS physics. Also, in all liklihood, radiative , leptonic (b->s) should also be effected making Expts. With higher luminosities extremely rich and exciting!

More Related