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Large electroweak penguin effects Large electroweak penguin effects in B and K physicsin B and K physics

Makiko Nagashima (NTU)Makiko Nagashima (NTU)

Theory seminar KEK, Sep. 6 Theory seminar KEK, Sep. 6 (2005)(2005)

HEP seminar at IOPAS, Oct. 28 HEP seminar at IOPAS, Oct. 28 (2005)(2005)

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Contents

Kπ DCPV puzzle within 4th generation model W.S.Hou, M.N, A. Soddu, Phys. Rev. Lett. 95, 141601(2005)

4th generation model and indications from Kπ and K physics W.S.Hou, M.N, A. Soddu, hep-ph/0508237, to appear in PRD

An enhanced

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IntroductionIntroductionStandard Model and CKM mechanism

3 generation

SU(2) doublet

SU(2) singlet

Quark sector

3 mixing angles

1 CP phase

CKM matrix

Unitarity Triangle Study of CPV / Test of SM / Search for NP

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Three sides are comparable

B physics has success in studying of CP violation

In this talk, We will see

and for Bs system

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Observables of CP Violation

Direct CP asymmetryDirect CP asymmetry

We focus on DCPV in this talk

see directly the difference of yield

Time dependent CP asymmetryTime dependent CP asymmetry

BB f

( Direct CPV )

( Mixing-induced CPV )

Only for neutral meson

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Terminology: TREE and PENGUIN diagrams

Tree diagram

su

u

d d

bW

b

u

u

u

u

s

W>1/Nc

b

d

W

g u

s

d

u

Penguin diagram

b

d

u

s

d

u

W

Z,γ

>

sub-dominant

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Part IPart ILarge EWP effects on B→Kπ Direct CP

PDG2002

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Result on DCPV in Kπ

PUZZLE

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The large discrepancy still persists

Lepton-Photon Symposium ‘05Lepton-Photon Symposium ‘05

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PQCD by Keum, Li and Sanda, PRD63(2001)054008PQCD by Keum, Li and Sanda, PRD63(2001)054008

Theoretical calculations in 2001Theoretical calculations in 2001

QCDF by M. Beneke et al., NPB606(2001)245QCDF by M. Beneke et al., NPB606(2001)245

Two of DCPV behaves similarTwo of DCPV behaves similar

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Improved calculations

Beneke and Neubert, NPB675(2003)333Beneke and Neubert, NPB675(2003)333

Annihilation contributionsAnnihilation contributions

H-n. Li, S. Mishima and A.I. Sanda, hep-ph/0508041H-n. Li, S. Mishima and A.I. Sanda, hep-ph/0508041

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Direct CP Violation (DCPV)

Difference of Yields

vs given by single term

no relative phases

DCPV goes away

CP

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QCDF (BBNS)

SM

kT PQCD (KLS)

away

sub-dominant

If one neglects EWP and C, No phase differences

(2003) (2001)

contradiction

up to leading order calculation

In K pi amplitudesIn K pi amplitudes

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How to explain deviation ?

The SM can explain The SM can explain the different pattern of DCPVs the different pattern of DCPVs in Kpi modes completelyin Kpi modes completely

Of course, it is fine !!Of course, it is fine !!

From this aspect,From this aspect,The different pattern of DCPVs remains a crucial hint of New Physics.The different pattern of DCPVs remains a crucial hint of New Physics.

New Physics exists, its contribution appear in other processes, New Physics exists, its contribution appear in other processes, and can be tested. and can be tested.

This does not mean THERE IS NO NEW PHYSICS IN OUR NATUREThis does not mean THERE IS NO NEW PHYSICS IN OUR NATURE

THE SM and THE NP can not be distinguished in Kpi DCPVsTHE SM and THE NP can not be distinguished in Kpi DCPVs

What can we learn for New Physics from Experimental results ? What can we learn for New Physics from Experimental results ?

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extra comparable contributionsbringing phase differencestoward

We call for Large with an extra weak phase

We employ kTPQCD approach

must not be negligible

Assemble

4th generation scenariopenguinNew physics

naturally explain largenaturally explain large

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kTPQCD approach

Large strong phase comes from annihilation process

a hard gluon kicks spectator

At leading process

is introduced to cure the endpoint singularities

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A. Arhrib and W-S. Hou, EPJC27,555

T. Yanir, JHEP06, 044

Minimum Setup ( meaning to be clear in Part II )

4th generation scenarioA sequential 4th generation in addition to the SM particles

well-known

unknown

same quantum number

follows WS parameterization

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Our assumption

Neither Scalar OPE nor Tensor OPE.R.H. dynamics is suppressed by ms/mb

The low energy operators are the same as the SM

New physics enters though loop processes,and changes the short distance effects

Buras, et al. Minimal flavor violationBuras, et al. Minimal flavor violation

Barger, et al. Z’ modelBarger, et al. Z’ model

Baek, et al. Generic EWP Baek, et al. Generic EWP

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Effective Hamiltonian

Tree

QCD Penguin

EW/EM Penguin

t' effects well-satisfy b → sγrate and DCPV

Large enhancement

Wilson coefficient

Dividing ΔCi by QCD penguin

Natural ability of 4th generation to large enhancement of EWP

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Constraint

PDG04

PDG04

Belle(04)

B(b→sll) gets greatly enhanced

Δm is lower than EXP. bound

4th generation effects are not excluded!!

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Result

kTPQCD in the SM

4th generation+

sizable splitting between

Roughly,

described as

It naturally generates the phase diff. and sizable mag. of the extra term

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Our result is at leading order in kTPQCD.

A recent result finds a much larger color-suppressedtree (C) at next-to-leading order. is less negative (H-n. Li, S. Mishima and A.I. Sanda, hep-ph/0508041)

Remark

Comparably large C would allow more parameter space for the 4th generation

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Some CuriositiesSome Curiosities

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MICPV is rather little sensitive to strong phases Specially, MICPV due to b→s transition behaves like

naïve factorization + 4th gene.

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No Rescattering

Another framework:extra strong phase from Final State Interaction

Naïve Factorization ⊗ Final State RescatteringOtherwise Double Counting

George W.S. Hou, BCP JC, Oct. 14 (2002)

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We followed Mod.Phys.Lett. A18,1763 by C-K. Chua, W-S. Hou and K-C. Yang

It accounts for

(strong phase)

ICHEP04

(strong phase)

problem

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This FSI picture doesn’t help for resolving the puzzle

There is no solution

We performed analysis by incorporating t’ effects

re-scattering happens between

EW penguin would be brought into amplitude from

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Part IIPart IIExplore s→d and b→d implications

Naively assumed

did not care about

One may have suspicion that b→s would spill over into s→d is not necessarily ~ 0

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should be all intertwined …PLB 192 441 (1987) by W.S. Hou et al.

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Be moderate

From K pi study, we learned

Keep

We have some constraint on from

Imposebe close to the Cabibbo angle

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Allowed region from K processes

standard (1) is less stringent

(simulated dots)

(shaded region) (elliptic rings)depends on hadronic parameter R6 and R8

Bijnens (2)

We found(1)

(2)

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Outcome for

Current Upper Bound

It is very hard to measure but challenging…

We find enhancing to or even higher !!

It might be even larger than !!

we take

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Unfortunately, US government cancelled the KOPIO experiment

We will have to wait longer to see whether such effects is really present…

Let us hope this stimulates the program at JPARC !!

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Furthermore….. We also checked the impact on Bd and D system

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Summary

Starting point → Direct CP Violation in B→Kπ

4th generation is possible to generate Large EWP

Extend our study to Bd and K system( to, phenomenologically, understand the possibilities of having still fourth generation )

( )

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BACKUP SLIDEBACKUP SLIDE

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FROM PDG04Our anxiety

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We now know neutrinos have mass, will have CPV, andmore to be revealed. # of neutrino =3 is just one piece of info.

The rho parameter is less of a problem.The S parameter is the real problem (it ‘s so for most NP models.)

What the situation changes if the Higgs is not seen and actually heavy ?

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Extra generation vs. EW precision data V.A. Novikov et al., PLB529, 111

Ng

Δm

=sq

rt(m

U^2

-mD

^2)

[GeV

]

mH>113 GeV, mD=130 GeV

mN

[G

eV]

Ng

mD=200, mU=220, mE=100 [GeV]

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2D plots in different way