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Electroweak B Decays. Possibility of Large EW Penguin contribution. T. Yoshikawa ( Nagoya ). This talk is based on S. Mishima and T.Y. hep-ph/0408090 and T.Y. Phys.Rev. D68, 054023 (2003). FPCP2004 Oct. 4 – 9, EXCO, Daegu, Korea. - PowerPoint PPT Presentation
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Electroweak B DecaysT. Yoshikawa ( Nagoya )Possibility of Large EW Penguin contribution FPCP2004 Oct. 4 9, EXCO, Daegu, Korea This talk is based on S. Mishima and T.Y. hep-ph/0408090 and T.Y. Phys.Rev. D68, 054023 (2003) .
B decaysQCD Color suppressed treeElectroWeakPenguin (PEW)AnnihilationSinglet QCD PenguinColor suppressed EW Penguin(PCEW )Gronau, Hernandez,London, Rosnerb
B decaysQCD Color suppressed treeElectroWeakPenguin (PEW)AnihilationColor suppressed EW Penguin(PCEW )Main Contributions T , P usually Negligible Contributions PCEW , A How should we treat PEW, C ?
Discrepancies between TH and EXThe direct CPVs are almost zero !! BUT the indirect CPV Ss are How about the differences among these b-s penguin modes ? Relations among the branching ratios Relation among Direct CP asymmetries We discuss what happens in B and decays . Fleischer-Mannel, Neubert-Rosner, Lipkin, Buras, T.Y., Gronau - Rosner, Buras-Fleischer et al , Li, . Many works.
K p - pp Puzzle Experimental data do not satisfy several relations among the branching ratios.0.37 0.16 0.43 0.20 0.83 0.23Before ICHEP04 TheoryExperimental There were quite large discrepancies.
Before ICHEP04 After ICHEP04 What changed ?
K p - pp Puzzle 1) Experimental data do not satisfy several relations among the branching ratios.0.21 0.11 0.22 0.14 0.66 0.13After ICHEP04 Still remaining the discrepancies !!
K p - pp Puzzle 2) There seems to be a discrepancy in direct CP asymmetries of B Kp .After ICHEP04 Theoretically, Exeimental data,Is the relation among the Acp s violated ?
We have to know what makes the discrepancies! Do we still need large EW Penguin contribution ?
Diagram Decomposition of B Kp and pp
Hierarchy in B K p QCD Color suppressed treeEW Penguin (PEW)Annihilation (Exchange)Color suppressed EW Penguin(PCEW )Gronau, Hernandez,London, RosnerbLargeSmall
They are rewritten as follows: where r is the ratio of each diagram with QCD Penguin, and dX is the strong phase difference. where r is the ratio of each diagram with Tree contribution, and dX is the strong phase difference. A (Exchange) and PCEW are neglected here.
Hierarchy Assumption in B KpO(0.1)O(0.01)
Hierarchy Assumption in B ppO(0.1)negligible
Branching ratios under the assumptionby neglecting r2 terms including rC, rcEW , rA (smaller terms than O(0.01 ). )
Fleischer-Mannel bound We can find several relations among them.
Some relations among the branching ratiosThese relation seems to be proportional to r2 so that they should be O(0.01) quantities .=0 or not ?
Branching ratios Rough estimation under assumption ~ 1 ?
Experimental data
= = = 0.21 0.110.22 0.140.26 0.16Do we need large EW penguin contribution ? Relations
1 s1 s0.14From the 1 s bound of Rc-Rn, S, R+ -2 with rT =0.2 We may still need slightly large EW penguin contribution. To discuss more detail, we need the information about strong phases. If flavor SU(3) sym. is good, dT ~ dEW and dT will be constrained by ACP . Consider about direct CP asymmetries !!
What can we expect No strong phase difference between tree and EW(Z) penguin bbWzusKKBB1)2)3)under SU(3) symmetry. Because the diagrams are topologically same.treeEW PenguinNeubert-Rosner,Buras and Fleischer
Direct CP asymmetries in B KpRelation among the CP asymmetries :Large EW Penguin ? Or Still early ?
Cos dT > 0 is favored. dT should be around 20o. Fleischer-Mannel bound-0.114 0.020as a function of dT with rT = 0.2 . dT should be around 20o or 150o dT
+
Maximum bound of Rc-Rn under constraints from ACP and R with rT = 0.2 . We still need large EW penguin contribution and large strong phase difference.is disfavored.
Large may be possible if there is SU(3) breaking effect between b-s P and b-d Penguins . BUT the magnitude will be constrainted from B KK (pure b-d penguin ) modes. dssKKPure b-s penguinPure b-d penguinAt largest, Pp is 1.5 times larger. We can not take so large .
How about B pp ? where .It seems to be difficult to explain by only EW penguin because it will be sub-leading contribution.To explain the large ratios, we need 1) To suppress the denominator . f1 + f3 > 90o with dT ~ 20o2) Larger rP 3) Larger (color suppressed tree ) Or New Physics ?? with new CP phase Before considering about New Physics, review the contribution from rC .
An example: f1+ f3 = 110o , dEW - dT =100o ,dC = dT
Relaxing the hierarchy assumption = keeping r2C terms in Kp. The lower bound of rC to satisfy Rc-Rn, S, R+ -2 at 1s bound. 1) d s are free parameters2) dT = dEW case If large is allowed, it may explain the discrepancies. Chiang-Gronau-Rosner-SuprumBut it seems to be too large though it is color suppressed tree-type contribution. The usual estimation is 0.02 .Charn-Li
ConclusionThe allowed region of rEW should be larger than about 0.2 . Still remaining the discrepancies ! Large strong phase differences are needed. SU(3) breaking ? As a possibility, we need to consider Large rc case also. Direct CP asymmetries will be more important to understand which is the origin of the discrepancies. To keep , need new CP phase in Penguin type diagrams. Or Large rc case.
If PEW is including New CP Phase, the effect must appear in CP asymmetries, Acp00 and SK0p0 .
Kppp(Kp pp w=0)or++Large f3 , dSU(3) breakingPossibility of New Physics ?or