Basics of Bs m Bs Bs mixing, B p and their recent experimental...

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Basics of Bs→ µ+µ−, Bs−Bs mixing, B→ πK and

their recent experimental implications

Seungwon Baek (KIAS)

Yonsei Univ.

Nov. 17, 2011

Selected issues in B-decays 2011-11-17 1 / 87

Outline

1 Introduction

2 Implications of CDF and LHC results of Bs→ µ+µ− on MSSM

3 Anomalous like-sign dimuon charge asymmetry and Bs−Bs-mixing

phases

4 B→ ππ and B→ πK puzzles

5 Current status of B→ πK puzzle and ACP(π0K0)

6 A solution to B→ ππ puzzle in the SM

7 B→ πK puzzle and NP models

8 Conclusions

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Introduction

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B-physics at B-factories and Tevatron

B-physics programs at current colliders have been very

successful.

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B-physics at the LHC era

LHCb is a dedicated detector for B-physics.

So B-physics will continue to be exciting at the LHC era. And it is

complementary to the direct NP searches at ATLAS and CMS.

Rare decays like Bs→ µ+µ−, Bs→ πK, Bd(s)−Bd(S) mixing,

Bs→ J/ψφ , Bs→ φφ , Bs→ K∗µ+µ−, Bs→ K+K− will be measured

with unprecidented precisions and will confirm NP or rule out

many NP models.

Precision measurements of the SM parameters, eg, the inner

angles of the unitarity triangle.

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Indirect Searches of New Physics

Probe particles running inside a loop, even ones too heavy to be

produced at colliders

Can study the flavor stucture

Complementary to the direct serch

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CKM matrix

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Unitarity Triangle

Unitarity of VCKM

VudV∗ub +VcdV∗cb +VtdV∗tb = 0

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Bs→ µ+µ−

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B(Bs→ µ+µ−)

SM prediction (helicity suppression decay)

B(Bs→ µ+

µ−)SM = (3.2±0.2)×10−9 (1)

CDF saw excess with 7 fb−1 CDF, arXiv:1107.2304

B(Bs→ µ+µ−)CDF = (1.8+1.1−0.9)×10−8

4.6×10−9 < B(Bs→ µ+µ−)CDF < 3.9×10−8 @ 90% CL

B(Bs→ µ+µ−)CDF < 4.0×10−8 @ 95% CL (2)

LHC results LHCb-CONF-2011-047, CMS, arXiv:1107.5834

B(Bs→ µ+µ−)LHC < 1.1×10−8 @ 95% CL (3)

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B(Bs→ µ+µ−) in the MSSMB(Bs→ µ+µ−)

∝ A2t µ2 tan6 βm−4

A Max(µ,mstop)−4 (D. Hooper & C. Kelso,

arXiv:1107.3858)

Bs→ µ+µ− diagrams

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Implications of CDF measurement on MSSM(D. Hooper & C. Kelso, arXiv:1107.3858)

Figure: Upper (Lower) panel: without (with) relic density constraint

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Implications of CDF measurement on MSSM(D. Hooper & C. Kelso, arXiv:1107.3858)

Regions consistent with thermal

relic density

χ coannihilates with τ1

A-resonance region

(2mχ0≈ mA)

A(χ χ→A→ bb,ττ)∝ tan2 β/m2A

Figure: black: bino-like, red: wino or

higgsino-like

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Implications of CDF measurement on MSSM(D. Hooper & C. Kelso, arXiv:1107.3858)

Constraints from direct

detection experiments

only a small fraction of

allowed parameters are

excluded

next generation

experiments can test

large region Figure: SI elastic scattering cross section for

χ0 with nucleons. Blue line: constraint from

XENON-100.Selected issues in B-decays 2011-11-17 14 / 87

SUSY breaking modelsSB, P. Ko, W.Y. Song, PRL(2002); JHEP(2003)

B(Bs→ µ+µ−) be sensitive to SUSY models, mSUGRA, AMSB,GMSB, · · ·

I different models predict different specta and SUSY parametersI large correction to yb at large tanβ (HRS effect)

yb =gmb√

2mW cosβ

11+∆b tanβ

,

∆b ≈ 2αs

3πµM3 I(mb1

,mb2,mg) (4)

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mSUGRASB, P. Ko, W.Y. Song, PRL(2002); JHEP(2003)

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mAMSBSB, P. Ko, W.Y. Song, PRL(2002); JHEP(2003) Ruled out by the lower

bound of CDF, although allowed by (g−2)µ and Higgs mass

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GMSBSB, P. Ko, W.Y. Song, PRL(2002); JHEP(2003) Allowed for large tanβ if

B(Bs→ µ+µ−)≈ 1.0×10−8.

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Correlation with direct detection experimentsSB, Y.G. Kim, P. Ko, JHEP(2005)

For large tanβ both Bs→ µ+µ−

and χN elastic scattering are

dominated by heavy Higgs

Strong correlation is expected

Bs→ µ+µ− constraint is much

stronger than the most

sensitive direct search bound

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Bs−Bs mixing

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Anomalous like-sign dimuon charge asymmetry

Baryon asymmetry of the universe requires new source of CP

violation(s): it may appear in B-decays

Like-sign dimuon charge asymmetry

Absl =

N++b −N−−b

N++b +N−−b

(N±±b : bb→ µ±

µ±). (5)

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Anomalous like-sign dimuon charge asymmetry

In terms of the semileptonic (“wrong sign”) charge asymmetry

Absl = (0.594±0.022)ad

sl +(0.406±0.022)assl,

aqsl =

Γ(Bq→ µ+X)−Γ(Bq→ µ−X)Γ(Bq→ µ+X)+Γ(Bq→ µ−X)

=|p/q|2−|q/p|2

|p/q|2 + |q/p|2(6)

⇒ CP violation in mixing

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Anomalous like-sign dimuon charge asymmetry

The SM prediction:

Absl(SM) = (−0.028+0.005

−0.006)% (7)

With 9 fb−1 data, D0 measured D0, arXiv:1106.6308

Absl(D0) = (−0.787±0.172±0.093)% (8)

⇒ 3.9 σ deviation.

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CP violation in Bs−Bs mixing

Assuming CPT, mixing of neutral B mesons is described by

iddt

(B0

s

B0s

)=

(M− i

2 Γ M12− i2 Γ12

M21− i2 Γ21 M− i

2 Γ

)(B0

s

B0s

)(9)

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CP violation in Bs−Bs mixing

Mixing parameters ( φs = arg(−Ms12/Γs

12))

BL = pB0s +qB0

s , BH = pB0s −qB0

s ,

∆Ms = 2|Ms12|, ∆Γs = 2|Γs

12|cosφs

qp

= −e−iφ sM

(1−

|Γs12|

2|Ms12|

sinφs

)as

sl =|Γs

12||Ms

12|sinφs (10)

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CPV phase φJ/ψφs from Bs→ J/ψφ(f0)

LHCb results LHCb-CONF-2011-049,LHCb-CONF-2011-051

φs = φM−2φD = 0.03±0.16(stat)±0.07(syst) rad

∆Γs = 0.123±0.029(stat)±0.011(syst) ps−1 (11)

agree well with the SM predictions.

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Pete Clarke, LHC workshop

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New Physics in the Γ12

The discrepancy between assl and Bs→ J/ψφ could be resolved by

considering NP contribution in Γs12

Although b→ scc of the SM is tree-level, it is λ 2 suppressed.

The NP contribution to operator b→ sττ is only weakly

constrained. SB, Alok, London, JHEP (2011), Bobeth, et.al., 1109.1826

NP in Γs12

assl =|Γs

12||Ms

12|sinφs =

|Γs12||Ms

12|sin(φ s

M−φsΓ). (12)

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Non-universal Z′ model

Tree-level FCNC possible

L Z′FCNC =− g

cosθW

[sγ

µPLBLsbb+(L↔ R)

]Z′µ +h.c. , (13)

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Non-universal Z′ model

SB, Alok, London, JHEP (2011)

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B→ ππ and B→ πK puzzles

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Nonleptonic decays B→ ππ and B→ πK

At quark level, b→ d(s)qq, (q = u,d)

Effective theory at mb�MW ,

Heff = ∑i

ci(µ)Oi(µ)

Theories for

〈M1M2|Oi(µ)|B〉

: naive factorization, generalized factorization, QCDF, PQCD,

SCET, ....

⇒ No standard theory, yet...

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The B→ πK decays as a test of CKM framework

Four B→ πK decays, related by isospin

A(B0→ π−K+)−

√2A(B+→ π

0K+)+√

2A(B0→ π0K0)−A(B+→ π

+K0) = 0 .

In terms of diagrams, Penguin (P′tc and P′uc), tree(T ′),

color-suppressed tree (C′), annihilation (A′), color-favored

(suppressed) EW penguin (P′(C)EW ),

A+0 = −P′tc +P′uceiγ +A′eiγ − 13

P′CEW ,

√2A0+ = +P′tc− P′uceiγ −T ′eiγ −C′eiγ −A′eiγ − P′EW−

23

P′CEW ,

A−+ = +P′tc−P′uceiγ −T ′eiγ − 23

P′CEW ,

√2A00 = −P′tc +P′uceiγ −C′eiγ −P′EW−

13

P′CEW . (14)

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Gronau, Hernandez, London, Rosner(1994,1995)

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The B→ πK

Or more compactly,

A+0 = p′ ,√

2A0+ = −p′− t′− c′ ,

A−+ = −p′− t′ ,√

2A00 = p′− c′ , (15)

where

p′ = −P′tc +P′uceiγ − 13

P′CEW ,

t′ = T ′eiγ +P′CEW ,

c′ = C′eiγ +P′EW . (16)

(T ′eiγ ,P′CEW) and (C′eiγ ,P′EW) appear in pairs.

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B→ ππ

Topological amplitudes of B→ ππ decays

√2A(B+→ π

0) = −(

Teiγ + Ceiγ)

A(B0→ π+

π−) = −

(Teiγ +Ptce−iβ

)√

2A(B0→ π0π

0) = Ptce−iβ − Ceiγ

where T = T +Puc, C = C−Puc

Isospin relation:

√2A(B+→ π

0) = A(B0→ π+

π−)+

√2A(B0→ π

0)

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Using flavor SU(3), we can relate the EWP to the trees: Neubert,

Rosner(1998), Gronau, Pirjol, Yuan (1999)

P′EW ≈ −0.60T ′

P′CEW ≈ −0.60C′.

The SU(3) breaking is estimated to be less than 5 % Neubert,

Rosner(1998)

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The B→ πK decays as a test of CKM framework

Hierarchy between the diagrams: (B→ πK) Gronau, Hernandez,

London, Rosner(1994,1995)

1 : P′tcO(λ ) : |T ′|,P′EW

O(λ2) : |C′|,P′uc,P

′CEW

O(λ3) : |A′|

λ = 0.2−0.3

(B→ ππ)

1 : |T|O(λ ) : |C|, |P|O(λ

2) : PEW

O(λ3) : PC

EW

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Time dependent CP-asymmetries

The time-dependent CP asymmetry:

ACP(∆t) ≡ ΓB0(∆t)−ΓB0(∆t)ΓB0(∆t)+ΓB0(∆t)

= SCP sin∆m∆t+ACP cos∆m∆t

ACP =−CCP =−1−|λCP|2

1+ |λCP|2, SCP =− 2ImλCP

1+ |λCP|2, λCP =

qp

AA

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The experimental data as of 2010 (2007)

Mode B(10−6) ACP SCP

B+→ π+K0 23.1±1.0 0.009±0.025

(23.1±1.0) (0.009±0.025)

B+→ π0K+ 12.9±0.6 0.050±0.025

(12.8±0.6) (0.047±0.026)

B0→ π−K+ 19.4±0.6 −0.098+0.012−0.011

(19.7±0.6) (−0.093±0.015)

B0→ π0K0 9.5±0.5 −0.01±0.10 0.57±0.17

(10.0±0.6) (−0.12±0.11) (0.33±0.21)

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The experimental data as of 2008

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B→ ππ,B→ πK puzzles

In the SM, we expect

B(B→ π0π

0) ≈ O(λ 2)×B(B+→ π+

π0)

ACP(B+→ π0K+) ≈ ACP(B0→ π

−K+)

SCP(B0→ π0K0) ≈ sin2β

However, experimental data violate these relations significantly!!

B→ ππ puzzle, B→ πK puzzle

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ACP(π−K+) vs ACP(π

0K+)

If |C′| � |T ′|, ACP(π−K+)≈ ACP(π

0K+).

However, the data show,

ACP(π0K+)−ACP(π

−K+) = 0.148±0.028(5.3σ).

NP? Belle collaboration, Nature (2008); M. Peskin, Nature (2008)

Selected issues in B-decays 2011-11-17 43 / 87

ACP(π−K+) vs ACP(π

0K+)

|C′/T ′|= 0.58 and large negative arg(C′/T ′) can account for the

difference.

A0+CP ≈ −2

∣∣∣∣ T ′

P′tc

∣∣∣∣sinδT ′ sinγ−2∣∣∣∣ C′

P′tc

∣∣∣∣sinδC′ sinγ

A−+CP ≈ −2∣∣∣∣ T ′

P′tc

∣∣∣∣sinδT ′ sinγ

⇒ A0+CP−A0+

CP ≈−2∣∣∣∣ C′

P′tc

∣∣∣∣sinδC′ sinγ = 0.148±0.028

Selected issues in B-decays 2011-11-17 44 / 87

ACP(π−K+) vs ACP(π

0K+)

|C′/T ′|= 0.58 is okay with QCD calculations.Bauer, Pirjol, Rothstein, Stewart, PRD(2004); Bauer, Rothstein, Stewart,

PRL(2005)

Beneke and Jager, NPB(2006)

Li and Mishima, arXiv:0901

large negative δC′ is accounted for only in Li and Mishima,

arXiv:0901

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Current status of B→ πK puzzleand ACP(π

0K0)

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The SM Fit 1

χ2min/d.o.f .(c.l.) |P′tc| |T ′| |C′| |P′uc|0.52/1(47%) 67.7±11.8 19.6±6.9 14.9±6.6 20.5±13.3

δT′ δC′ δP′uc β γ

(6.0±4.0)◦ (−11.7±6.8)◦ (−0.7±2.3)◦ (21.66±0.95)◦ (35.3±7.1)◦

Table: Results of the fit to P′tc, T ′, C′, P′uc , β and γ in the SM. The fit includes the constraint β = (21.66+0.95−0.87)

◦. The amplitudeis in units of eV.

Better fit than to 2007 data (SB and D. London, PLB(2007)) where

|C′/T ′|= 1.6±0.3.

γ too small. cf) CKM fit γ = (66.8+5.4−3.8)

◦.

|P′uc| is large, although so is its error.

B→ πK not good to get γ.

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The SM Fit 2

χ2min/d.o.f . |P′tc| |T ′| |C′| |P′uc|

3.2/2(20%) 50.5±1.8 5.9±1.8 3.4±1.0 2.3±4.9

δT′ δC′ δP′uc β γ

(25.5±11.2)◦ (252.0±36.1)◦ (−9.9±27.8)◦ (21.65±0.95)◦ (66.5±5.5)◦

Table: Results of the fit to P′tc, T ′, C′, P′uc, β and γ in the SM. The fit includes

the constraints β = (21.66+0.95−0.87)

◦ and γ = (66.8+5.4−3.8)

◦. The amplitude is in units

of eV.

Good agreement with the naive power counting, although |T ′/P′tc|rather small and |C′/T ′| rather large.

large negative δC′ should be understood theoretically.

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Best fit values of the B→ πK observables

Obs. Fit 1 Fit 2

BR(π+K0) 23.1 (+0.02) 23.7 (−0.57)

ACP(π+K0) 0.014 (−0.21) 0.016 (−0.29)

BR(π0K+) 12.9 (−0.03) 12.5 (+0.72)

ACP(π0K+) 0.05 (+0.15) 0.04 (+0.27)

BR(π−K+) 19.4 (+0.05) 19.7 (−0.46)

ACP(π−K+) −0.098 (−0.04) −0.097 (−0.12)

BR(π0K0) 9.8 (−0.07) 9.3 (+0.88)

ACP(π0K0) −0.08 (+0.66) −0.12 (+1.10)

SCP(π0K0) 0.58 (−0.03) 0.58 (−0.08)

Table: Predictions of the B→ πK decay observables. Numbers in parentheses

are the corresponding pulls. pull ≡ (data-theory prediction)/(data error)

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Predictions of the B→ πK observables

The prediction ACP(π0K0) =−0.12 has the largest deviation from

the data.

BaBar and Belle data are inconsistent in the central values of

ACP(π0K0).

Source N(BB) (M) ACP(π0K0)

BaBar 467 −0.13±0.13±0.03

Belle 657 0.14±0.13±0.06

Average 1124 −0.01±0.10

The SM favors the BaBar data.

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NP contributions

p′→ p′+P′NPeiΦ′P (NP Fit 1)

c′→ c′+P′EW,NPeiΦ′EW (NP Fit 2)

t′→ t′+P′CEW,NPeiΦ′CEW (NP Fit 3)

NP strong phase is small, δNP = δT′ A. Datta and D. London,

PLB(2004)

For NP fits, we impose β = (21.66+0.95−0.87)

◦ and γ = (66.8+5.4−3.8)

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NP strong phaseThe strong phase, eg., of P′c

NP strong phase comes only from self-rescattering

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NP 1 χ2/d.o.f . |P′tc| |T ′| |C′|3.6/2(17%) NA 5.9±2.0 3.6±1.0

|P′NP| δC′ δNP Φ′P

NA NA NA NA

NP 2 χ2/d.o.f . |P′tc| |T ′| |C′|0.4/2(82%) 48.2±1.3 2.6±0.4 16.1±28.4

|P′EW,NP| δC′ δNP Φ′EW

20.1±22.3 (254.8±21.8)◦ (95.4±9.6)◦ (37.6±51.8)◦

NP 3 χ2/d.o.f . |P′tc| |T ′| |C′|2.5/2(28%) 48.2±1.3 1.9±1.4 9.4±2.3

|P′CEW,NP| δC′ δNP Φ′CEW

16.5±15.2 (192.4±12.3)◦ (97.8±15.3)◦ (183.9±7.8)◦

Predicts too large C′ in the 2nd and 3rd case.

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Predictions of ACP(π0K0)

SM 2 NP 1 (P) NP 2 (EW) NP 3 (EWC)

−0.12 −0.12 −0.03 −0.03

The predictions of ACP(π0K0) are very distinctive depending on

models.

Therefore, ACP(π0K0) can be used to distinguish different models,

if theoretical and experimental errors become smaller. SB, C-W.

Chiang, M. Gronau, D. London, J. L. Rosner, arXiv:0905.1495

Selected issues in B-decays 2011-11-17 54 / 87

Sum rules and ACP(π0K0)

In the SM, ACP(π0K0) can be predicted quite reliably.

The dominant ∆I = 0 term (p′) is canceled in

2|A0+|2 +2|A00|2−|A+0|2−|A−+|2

= |p′+ t′+ c′|2 + |p′− c′|2−|p′+ t′|2−|p′|2

= 2(|c′|2 +Re(t′c′∗))

The RHS is small compared with the dominant |p′|2 in the SM.

Selected issues in B-decays 2011-11-17 55 / 87

Sum rules and ACP(π0K0)

Sum rule for the branching ratios M. Gronau and J. L. Rosner,

PRD(1999), H. J. Lipkin, PLB(1999)

2B(π0K+)+2(τ+/τ0)B(π0K0) = (τ+/τ0)B(π−K+)+B(π+K0) .

where τ+/τ0 = 1.073±0.008

Numerically

46.8±1.8 = 43.9±1.2(1.3σ)

The B has been measured precisely and all the SM and NP fits

confirm the rate sum rule.

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Sum rules and ACP(π0K0)

Sum rule for the ACP M. Gronau, PLB(2005)

ACP(π−K+)+ACP(π

+K0)' ACP(π0K+)+ACP(π

0K0) .

where B(π0K+) : B(π0K0) : B(π−K+) : B(π+K0) = 1 : 1 : 2 : 2 is

assumed.

Prediction ACP(π0K0) =−0.139±0.037

Taking into account of the correct values of B,

ACP(π0K0) =−0.149±0.044

These sum rule predictions of ACP(π0K0) are consistent with the

values obtained in the SM fits: ACP(π0K0) =−0.08 (SM Fit 1)

−0.12 (SM Fit 2)

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Sum rules and ACP(π0K0)

Sum rules can be significantly violated with the presense of

sizable ∆I = 1 NP amplitude.

With P1 ≡ PEW,NP and P2 ≡ PCEW,NP, the terms violating the rate sum

rule are

2[|P1|2 + |P1||P2|cos(δ1−δ2)cos(φ1−φ2)] ,

where δ1,δ2 and φ1,φ2 are the strong and weak phases of P1 and

P2.

The term violating the asymmetry sum rule is

2|P1||P2|sin(δ1−δ2)sin(φ1−φ2) ,

which is violated significantly only when P1 6= 0, P2 6= 0, δ1 6= δ2

and φ1 6= φ2

Selected issues in B-decays 2011-11-17 58 / 87

Sum rules and ACP(π0K0)

Model ACP(π0K0) LHS of rate SR RHS of rate SR

SM 2 −0.12 44.8 44.8

NP 1 −0.12 44.9 44.8

NP 2 −0.03 46.9 43.9

NP 3 −0.03 45.3 44.6

NP models can violate the asymmetry sum rule significantly while

preserving the rate sum rule.

Selected issues in B-decays 2011-11-17 59 / 87

A solution to B→ ππ puzzlein the SM

Selected issues in B-decays 2011-11-17 60 / 87

B→ ππ puzzle

|C||T|

= 0.71±0.18

Selected issues in B-decays 2011-11-17 61 / 87

A solution to B→ ππ puzzle

The T, C appear only in combinations of

T = T +Puc, C = C−Puc

If there is a constructive (destructive) interference between C (T)

and Puc, the puzzle is solved

The Puc can be extracted from the B→ KK. SB, PLB(2008)

Selected issues in B-decays 2011-11-17 62 / 87

A solution to B→ ππ puzzle and B→ KK

Assuming flavor SU(3) symmetry, we get Puc from the B→ KK

(r = |Puc/Ptc|,δuc = arg(Puc/Ptc) )

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A solution to B→ ππ puzzle and B→ KK

r and δuc can be determined with two-fold ambiguity.

The black dot solution is favored in the SM.

The ambiguity is lifted when SKK is measured with more precision.Selected issues in B-decays 2011-11-17 64 / 87

A solution to B→ ππ puzzle and B→ KK

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B→ πK puzzleand NP models

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B→ πK puzzle and NP

Two NP scenarios giving large EWP:I A SUSY scenario by Grossmann, Neubert, Kagan (GNK) SB,

Imbeault, London (2008)I Leptophobic Z′ SB, J. Jeon, C.S. Kim (2008)

Other studiesI Large 2-3 mixing in the u-quark sector. Khalil (2005), Khalil,

Masiero, Murayama (2008)I R-parity violating SUSY Yang, Wang, Lu (2006)

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SUSY GNK scenario

Z(γ)-mediated EW-penguin in MSSM is suppressed.

”Trojan penguin?” Grossmann, Neubert, Kagan(1999)

Large enhancement in EWP is possible:

α2s /M2

SUSY

α2ew/M2

W

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Structure of squark mass matrix

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Large SUSY contributions is possible when

gluino mass is small

m2sL,R� m2

bL,R

sin2θL or sin2θR not far below from 1

m2dR� m2

uRcf. m2

dL= m2

uLby SU(2)

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∆ms constraint

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∆ms constraint

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∆ms constraint

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B→ πK in GNK scenario

12 SUSY parameters

Generated 500,000 points in the region

300≤ mg ≤ 2000 GeV,

100≤ mq ≤ 2000 GeV,

−π/4 < θL,R < π/4

−π < δL,R < π

γ = 67.6+2.8◦−4.5

Accepted a SUSY point as a ”solution” if χ2min < 11.31 (dof=9-4) (2

σ ) of fitting P and T to the 9 data

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Also imposing ∆ms/∆mSMs = 0.788±0.195 at 2 σ , we get only small

number of ”good” solutions.

Table 2The number of points (out of 500000) which satisfy χ2

min(B → π K ) < 11.31, the

�ms constraint within ±2σ , and both constraints. In the left table, only LL mixing

is allowed, while in the right table, both LL and RR mixings are allowed

χ2min

< 11.31 �ms both

74 414357 15

χ2min

< 11.31 �ms both

102 92844 1

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Leptophobic Z′ scenario

In the flipped SU(5) GUT with

If Z′ couples only to F, it becomes leptophobic. Lopez, Nanopoulos

(97)

The Z′ coupling can be generation dependent and generate FCNC

at tree-level.

The couplings allow large CPV.

Maximally violates the isospin symmetry in the right handed

quarks.→ New source of EW penguin.

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Lagrangian SB, Jeon, Kim (08)

∆ms constraint:

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∆ms constraint (cont’d):

∆ms alone is not effective when

both L and R couplings exist

simultaneously.

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Leptophobic Z′

BR(B→ πK) can be used to constrain (L,R) space.

PQCD results (Li, Mishima, Sanda (05)) for the SM amp. and naive

factorization for the NP amp. are used.

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Leptophobic Z′

The EWP can be enhanced considerably even after imposing ∆ms

and BR(B→ πK).

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Leptophobic Z′

Anomalies in SCP and ACP can be explained simultaneously.

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Conclusions

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Conclusions

In MSSM, CDF excess of Bs→ µ+µ−: tanβ & 20, correct relic

density, most allowed region is sensitive to next generation direct

detection experiments.

Bs→ µ+µ− plays unique role in probing and discriminating SUSY

models

mAMSB model is excluded by the CDF lower bound

In some SUSY models Bs→ µ+µ− constraint is much stronger

than the DM direct search experiments

The D0 anomalous like-sign dimuon charge asymmetry and the

φJ/ψφs can be reconciled by allowing NP contribution to Γs

12.

New Physics in b→ sττ operator is the most promising

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Conclusions

There are puzzles in the B→ ππ and B→ πK decays.

The B→ πK puzzles:I The B→ πK puzzle seems to have almost disappeared, but we still

need to understand . . .

F The discrepancy between SM prediction ACP(π0K0) =−0.149±0.044

and the exp. value AWACP (π

0K0) =−0.01±0.10F More theory inputs to predict CP asymmetries reliably

I More precise measurement of ACP(π0K0) will allow the probe of NP

in ∆I = 1 transition amplitude.

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Conclusions

The B→ ππ puzzle can be solved in the SM.

NP models significantly contributing to B→ πK decays:I The trojan penguin in the GNK model in the MSSM.I The leptophobic Z′ scenario can solve the puzzles naturally.

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