Testing the SM with penguindominated Bdecays Amarjit Soni

Testing the SM with penguindominated 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? 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

Questions for the Super-B Workshop

Brief Recapitulation: Basic Idea Dominant decay amp. has 0 weak phase [just as in B->ψKS] up to O(λ 2)

Brief remarks on the old study(with London, PLB’ 97) • • • Originally motivated by then. CLEO discovery of Huge inclusive (see Browder. . ) as well as exclusive For DIRCP see also Hou&Tseng, ’ (see J. Smith…) Brs. into η PRL’ 98 Suggest with Atwood(PLB 97; PRL 97) 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 sin 2φ1(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

J. Smith@CKM 05 WA ~ 2. 7σ

Averaging issue: Are we making a 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

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, f 0, K 0 K 0…)K 0 , (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)

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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

HYC-CKM 05

B K All rescattering diagrams contribute to penguin topology, dominated by charm intermediate states fit to rates r. D = r. D* 0. 67 Should reduce model dependence predict direct CPV Significantly for CPV

HYC-CKM 05

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 K & HUGE for ρ K (~ -46%)

BR SD -6 (10 ) BR with FSI (10 -6) BR Expt (10 -6) DCPV SD 16. 6 22. 9+4. 9 -3. 1 24. 1 1. 3 0. 01 0. 026+0. 00 -0. 002 -0. 02 0. 03 B 0 K- 13. 7 19. 7+4. 6 -2. 9 18. 2 0. 8 0. 03 -0. 15+0. 03 -0. 01 -0. 11 0. 02 B- 0 K- 9. 3 12. 1+2. 4 -1. 5 12. 1 0. 8 0. 17 -0. 09+0. 06 -0. 04 B 0 K 0 6. 0 9. 0+2. 3 -1. 5 1. 0 -0. 04 0. 022+0. 008 -0. 012 -0. 09 0. 14 _ B- -K 0 _ _0 + _ DCPV with FSI DCPV Expt l Only LD uncertainties due to form-factor cutoff are shown here. Total errors=SD+LD, for example, l FSI yields correct sign and magnitude for A( +K-) l P/T|SD=0. 12 exp(-i 177 ), P/TSD+LD=(0. 14 0. 01)exp[i(147 8) ]

Note the very large (~ -40%) DCP in ρ0 K- & ρ0 K 0

More remarks & ρ0 KS 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]

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!)

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

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[K 0, 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!