Testing Penguin-Dominated B-Decays in the Standard Model

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

8. 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

9. 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)

10. 10192

11. 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

12. HYC-CKM05

13. HYC-CKM05

14. HYC-CKM05

17. 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

19. HYC-CKM05

20. 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%)

22. _ _ _ _ • 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)]

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

24. 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]

25. 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!)

26. 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)

27. 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!