1 b experiments y.sakai kek 28-sep-2006, nasu - “b factories” - - cp violation & flavor...

11

B ExperimentsB Experiments

Y.Sakai KEK

28-Sep-2006, Nasu

- “B Factories” -

- CP Violation & Flavor Physics -

22

Goal of B experimentsGoal of B experiments

Discovery of CPV in B decay Discovery of CPV in B decay

Precise test of KM(CPV) and SM Precise test of KM(CPV) and SM

Search/Evidence for New Physics Search/Evidence for New Physics

Step1

Step2

Step3

Now

2001 summer !

B decays QCD/Lattice, New ResonancesAlso, excellent /charm factory

main

33

SymmetriesSymmetries

Nature and its Law: ~ Symmetry = Beauty

P, C, T : most Fundamental Symmetry

P : Parity = Space inversionC : Charge conjugate ( Particle Anti-particle; Quantum #) [Lagrangian Hermitian conjugate]T : Time reversal [c-number complex conjugate]

CPT Theorem Lorentz invariant local quantum field theory CPT symmetry

Particle Anti-particle: Mass and Lifetime are identical

44

P& C ViolationP& C Violation

1956: Lee-Yang predict P violation1957: discovered by C.S.Wu in 60Co -decay

e

Spin

６６６６ Pe

Spin

６６６６６６６６６６６６

Weak Interaction VA

６６６６６６６６６６６

P ViolationP Violation

C violationC violation

Simple Illustration

L-handed L-handed

R-handedPL = +1

L = 1

Physical Particle Anti-particle : CPPhysical Particle Anti-particle : CP

C

55

CP ViolationCP Violation

1964: discovered in K0 decay (J.Cronin, V.Fitch et. al.)

Observation of KL +- CP Violation

002

001

KKK

KKK [CP=+1]

[CP=1]

[K0-K0 mixing]

K1=KS, K2=KL

KS+- （ CP ＝＋１） , KL+-0 （ CP ＝ー１）

６６６６６６６６６６６

If CP conserves

Branching fraction = 2.3x10-3

CPV: difference in behavior of particle and anti-particle

_

66

Why CPV is Important ?Why CPV is Important ?

Universe: almost “matter” only (no anti-matter)

Big-Bang N(particles) = N(anti-particles)

Sakhalov’s 3 conditions (1967): 1. baryon number violation 2. CP violation 3. existence of non-equiblium

Andrei Sakharov (1921-1989)

CPV is a key for Existence of Universe & us !

77

Origin of CPV ?Origin of CPV ?

Kobayashi-Maskawa AnsatzKobayashi-Maskawa Ansatz (1973)

Complex phase in the quark mixing matrix source of CPV in Weak Interactions

Requires 3 (or more) generation of quarks

• only 3 quaks (u, d, s) were known at that time !

• All 6 quarks are now discovered

Essential ingredient of the Standard Model (SM)

KM-phase

KM-phase

88

CKM matrixCKM matrix

b

s

d

VVV

VVV

VVV

b

s

d

tbtstd

cbcscd

ubusud

'

'

'

2

2

)1(

2/

)(2/

AiA

A

iA

CKM matrix

Wolfenstein representation

dj

uk

W-

Vkj

= sinc ) c: Cabibbo angle

Weak Interaction(charged current)

+ O(4)

99

Unitarity TriangleUnitarity Triangle

1

2

3

udubVV tdtbVV

cdcbVV

3 A(1 i)3 A( i)

3A

()

()

()0VVVVVV tdtbcdcbudub

j=1(d), k=3(b)

V†V ＝ １ （ VijV*ik = ｊ k ）CKM matrix: unitary

cdcb

udubb VV

VVR

cdcb

tdtbt VV

VVR

Normalize by V*cbVcd (=A3)

(1,0)

()

|Rt|

1

|Rb|

()

()

()

Vcd Vcb*

Vtd Vtb*Vud Vub*

1010

CPV: Why B ?CPV: Why B ?

Size of CPV in K: O(10-3) ~ small not enough information to confirm KM scheme

upu

downd

charmc

stranges

topt

bottomb

Specialty of B long lifetime (~1.5 ps) Large B0-B0 mixing Various decay modes

Sanda-Bigi-Carter (1980)

Large CPV in B-system

1111

B0-B0 Mixing & CPVB0-B0 Mixing & CPV

__

B0

B0 ｆｃｐ

ｆｃｐ

B0

B0

A

A

=mixing

Initial: B0 B0

B0

_

W Wd

bt

tb

dB0

d B0d

Vtd

VtdVtb

Vtb

Oscillation

Interference Direct decay Mixing + Decay

d

b

d

cc

dW

B0d

S

J

Vus

Vcb

Decay: A

Time dependent CPVTime dependent CPV

SandaBigiCarter

Weak Phasedifference

_A

1212

CPV in BCPV in B

made by H. Miyake

(A = C )Mixing-induced CPVMixing-induced CPV Direct CPVDirect CPV

SandaBigiCarter

t

CPV in B: Time-dependent CPV CPV in B: Time-dependent CPV

2ImCP

CP S =

CP CP

A =

qpCP = A

A

tdtb

tdtb

VV

VV

p

q

mixing

A=A: No DCPV sin-term onlyA=A: No DCPV sin-term only

_

decay

1313

Discovery of b-quarkDiscovery of b-quark

[PRL 39, 252 (1977)]

(1S)

Lederman et al., Fermilab

p+N X

1977

e+e collider

1978~ ARGUS (Doris, DESY) CLEO (CSER, Cornell)

Not enough to observe CPV

1414

Asymmetric B FactoriesAsymmetric B Factories

PEP-II

BaBar~1 km in diameter

Mt. Tsukuba

KEKBBelle

8 GeV e8 GeV e-- x 3.5 GeV e x 3.5 GeV e++

11mrad crossing

9 GeV e9 GeV e-- x 3.1 GeV e x 3.1 GeV e++

Head-on collision

KEKB (Japan) PEP-II (USA)=0.425 =0.56

SLAC

1515

KEKB & PEP-IIKEKB & PEP-II

e+ source

Ares RF cavity

Belle detectorSCC RF(HER)

ARES(LER)

1616

Peak LuminosityPeak Luminosity

1.65x1034 1.21x1034

>1fb-1/day>1 M BB>1fb-1/day>1 M BB

_

1717

KEKB LinacKEKB Linac

1818

KEKB AcceleratorKEKB Accelerator

1919

KEKB AcceleratorKEKB Accelerator

ARES cavity

Superconductingcavity

2020

Integrated LuminosityIntegrated Luminosity

PEP-IIfor BaBar

KEKBfor Belle

KEKB + PEP-II

reached on July 13, 2006

~ 1 Billion BB pairs

Inte

grat

ed L

umin

osit

y (f

b-1)

~630 fb-1

~400 fb-1

2121

Belle & BaBar collaborationsBelle & BaBar collaborations

IHEP, Vienna

ITEP

Kanagawa U.

KEK

Korea U.

Krakow Inst. of Nucl. Phys.

Kyoto U.

Kyungpook Nat’l U.

EPF Lausanne

Jozef Stefan Inst. / U. of Ljubljana / U. of Maribor

U. of Melbourne

Aomori U.

BINP

Chiba U.

Chonnam Nat’l U.

U. of Cincinnati

Ewha Womans U.

Frankfurt U.

Gyeongsang Nat’l U.

U. of Hawaii

Hiroshima Tech.

IHEP, Beijing

IHEP, Moscow

Nagoya U.

Nara Women’s U.

National Central U.

National Taiwan U.

National United U.

Nihon Dental College

Niigata U.

Osaka U.

Osaka City U.

Panjab U.

Peking U.

U. of Pittsburgh

Princeton U.

Riken

Saga U.

USTC

Seoul National U.

Shinshu U.

Sungkyunkwan U.

U. of Sydney

Tata Institute

Toho U.

Tohoku U.

Tohuku Gakuin U.

U. of Tokyo

Tokyo Inst. of Tech.

Tokyo Metropolitan U.

Tokyo U. of Agri. and Tech.

Toyama Nat’l College

U. of Tsukuba

VPI

Yonsei U.

13 countries, 55 institutes, ~400 collaborators

2222

Belle and BaBar DetectorsBelle and BaBar Detectors

Si Vertex detector

Drift Chamber (small cell)

CsI(Tl) EM calorimeter

/KL detector (RPC+Fe)

SC solenoid (1.5T)

TOF counter &Aerogel Cherenkov DIRC

2323

Detector PerformanceDetector PerformanceA big “digital camera” that we use to take ~108 beautiful pictures/year.

O(1) ps

Good Resolutions Momentum Energy (EM)

Good PID e, , K, p, KL

Good Vertexing (decay point)

2424

1 Measurement 1 Measurement

_

d

b_ c

c

sd

_wB0J/

K0

CP : CP eigenvalue

V*td

V*td_ _

t

dt

b

b

d _ww B0B0

_

= cpsin21 sin(mt) +A cos (mt) A CP

Mixing induced CPV Direct CPV

A 0

1

2

3

Vtd Vtb

Vcd Vcb

Vud Vub*

*

*

First observed CPV in B (2001)

V*cb

2525

Time-dep CPV MeasurementTime-dep CPV MeasurementFlavor-tag (B0 or B0 ?)

J/(’)

KS

ee

zt=0fCP

Vertexing

Reconstruction

ExtractCPV

fitB0B0

B0-tag B0-tag

t z/c

eff ~30%

t~140ps

=0.425 (KEKB)0.56 (PEP-II)

same analysis method applied for all modes

2626

BB00 J/ J/ K KSS : Signals : SignalsBB00 J/ J/ K KSS : Signals : Signals

Ks+

~4MeV/c2

J/+

J/e+e

~11 MeV/c2

~10 MeV/c2

B0 J/ Ks(+ )

Golden modeGolden mode

2727

B-meson ReconstructionB-meson Reconstruction

Energy difference:

Beam-constrained mass:

2/

2 )()2(SKJCMbc ppEm

2/ CMKJ EEEES

Utilize special Kinematicsat Y(4S)

Mbc

535M BB

Nsig = 7482Purity 97 %

CP odd

B0 J/ KS

2828

BB00 J/ J/ K KLL : Signals : SignalsBB00 J/ J/ K KLL : Signals : Signals

pKL information is poor lower purity

535M BB

KKLL

KL direction + 2-body decay kinematics

Nsig = 6512Purity 59 %

CP even

2929

Flavor TaggingFlavor TaggingFlavor TaggingFlavor Tagging

ｂｄB0

ｓ

u

ｃK+

dー

_W+

l+

W-

l-

+

ー

D*

-slow

High-p (primary), low-p (secondary) leptonsStrangeness (b c s)Fast , slow

2-stage Multi-dim. Likelihood based method (incl. correlations) Neural Network

ー

utilize allavailable info.

__

3030

Vertex ReconstructionVertex ReconstructionSilicon Vertex detector

(z(zCPCP) ~ 75) ~ 75m m

(z(ztagtag) ~ 140) ~ 140mm

(z(zCPCP) ~ 75) ~ 75m m

(z(ztagtag) ~ 140) ~ 140mm

( )

zt

c

=

IP constrained fitIP constrained fit

3131

Fit : extract sin21 Fit : extract sin21

)21( wR : detector resolutionw : wrong tag fraction (misidentification of flavor) (1-2w) quality of flavor tagging They are well determined by using control sample D*l D(*) etc…

S = 0.65A = 0.00 B0 tag

_B0 tag

B0 tag_B0 tag

-CPsin21

Mixing of D*lGood tag region(O

F-SF

)/(O

F+SF

)

t| (ps)

)cossin(141

,1 tmAtmSetqPt

R

true

3232

sin21 : b ６ ccssin21 : b ６ ccs

B0 tag_B0 tag

_347M BB535M BB

_

BJ/Ks

BJ/KL

_(cc)K(*)0

[hep-ex/0608039] [hep-ex/0607107]

CP-even

CP-odd

0.710 0.034 0.019sin2= 0.642 0.031 0.017

3333

sin21 : Historysin21 : History

0.674 0.026

1137events

B0 tag_

B0 tag

Asy

mm

etry

31M BB

2001

CPV Observed !

3434

sin21 : Historysin21 : History

0.674 0.026

B0 tag_B

0 tag

535M BB

14000signals

2006

< 4% error !

3535

Determination of UTDetermination of UT

1

2

3

Vtd Vtb

Vcd Vcb

Vud Vub*

*

*

B0 (cc)K(*)0

B0 D*+D(*)-(K)

-

B D(*)l b c l

B DCPK

B0 D(*)+

B l b u l

B ,

fB: B lB (

((

Precise test of KM(CPV) and SM Precise test of KM(CPV) and SM

B experiments can provide all measurements !B experiments can provide all measurements !

3636

2 measurement2 measurement

1

2

3

Vtd Vtb

Vcd Vcb

Vud Vub*

*

* mixing

Penguin

d

b

d

d

u

u

W

B0d -

+

Vud

Vub

Tree

B0d

d

b

du

u

W

g +

-

VtdVtb

t d

S sin2 Isospin AnalysisIsospin Analysis

3737

3 measurement3 measurement

1

2

3

Vtd Vtb

Vcd Vcb

Vud Vub*

*

*

u

b

u

uc

sW

B+d

D0

Vcs

Vub

u

b

u

su

c

W

B+d D0

+Vus

Vcb _fCOMfCOM

interference

Simple mixing CPV 3 (with Bd )+

Tree

3 3

Tree

3838

|Vcb | & |Vub | measurements|Vcb | & |Vub | measurements

b c(u)

Vcb,Vub W-

l-

l

exclusive final states

inclusive final statestwo ways:two ways:

b c(u)

Vcb,Vub W-

l-

l

Semileptonic B deacys - reasonably good theoretical understanding

SEVERAL THEORETICAL APPROACHES TO HANDLE HADRONIC EFFECTS

|Vcb| < 2%

|Vcb| ~ 7%

3939

|Vtd | measurement|Vtd | measurement

W W

d

bt

tb

dB0

d B0d

Vtd

VtdVtb

Vtb

md = Cd BBd fBd2 |Vtb

* Vtd |2

BBd fBd=223 35 MeV

|Vtd| ~15% error

(~15% error)

( |Vtb| = 1)

md = 0.507 0.005 ps-1 (1% error)

[hep-ex/0609040]

Lattice QCD(unquenched)

ms = 17.77 0.10 0.07 ps-1

BBs fBsBBd fBd

(< 4% error)

= A2 (~2% error) =

|Vtd|

|Vts|

md mBs

ms mBd

>5

BsBs

4040

UT angle & Side measurementsUT angle & Side measurements

/2 = [93 ]+119

/3 = [71 ]+2230

|Vub/Vcb| ~ 7%

|Vtd /Vts| ~ 4%

4141

Summary of CKM/UT Summary of CKM/UT

KM-phase =source for CPV~ Established !

KM-phase =source for CPV~ Established !

Precise Test of SM (& search for NP effect)~ in progress(Need more Data)

Precise Test of SM (& search for NP effect)~ in progress(Need more Data)

4242

Rare B decays Rare B decays

CPV in B CPV in B

Search for New PhysicsSearch for New Physics

provide Powerful tool for Search NP ( New Phase )

In spite of Great Success of SM, there must be New Physics beyond it at High Energy scale

excellent opportunities for NP search

Loop diagramLoop diagram

Decays involving ( H)Decays involving ( H)

Decays (Lepton Flavor Violation = NP) : B-factory = -factory Decays (Lepton Flavor Violation = NP) : B-factory = -factory

Penguins [bs(d) , bs(d) l+l]

Key

4343

New physics Search :New physics Search :

b

dsd

X ss

’

KS

b

dsd

t ss

’

KS

_B0 +

b sqq CPV b sqq CPV--

+ New Physics with New PhaseSbs Sbc , A can 0

-

SM: bs Penguin phase = (cc) K0-

“b ccs: sin21” (SM reference) deviation

Vts Vtb*

4444

Experimental ChallengeExperimental Challenge

B0 ６ J/KS

B0 ６ KS

Tree

Penguin

We need1) large number of BB pairs2) additional background rejection

Event Shape Event Shape

e e qq

(Jet-like)e e 4 S B B

(Spherical)

much smallerBF

Continuum Suppression using Event Shape likelihood

4545

“Golden” mode:K0 “Golden” mode:K0

unbinned fitSM

“sin21” = 0.50 0.21 0.05

A = 0.07 0.15

0.06

“sin21” = 0.50 0.21 0.05

A = 0.07 0.15

0.06

535M BB

K0

[hep-ex/0607112]

“sin21” = 0.12 0.31 0.10

A = 0.18 0.20

0.10

“sin21” = 0.12 0.31 0.10

A = 0.18 0.20

0.10

_347M BB

[hep-ex/0608039]

4646

“Golden” mode:’K0 “Golden” mode:’K0

unbinned fitSM

“sin21” = 0.64 0.10 0.04

A = 0.01 0.07

0.05

“sin21” = 0.64 0.10 0.04

A = 0.01 0.07

0.05

1st observationb s mode tCPV

1st observationb s mode tCPV

535M BB 5.65.6

’K0

“sin21” = 0.58 0.10 0.03

A = 0.16 0.07

0.03

“sin21” = 0.58 0.10 0.03

A = 0.16 0.07

0.03

5.55.5

’Ks ’KL

_384M BB

[hep-ex/0608039] [hep-ex/0609052]

4747

2006: 1 with b ６ s Penguins2006: 1 with b ６ s PenguinsSmaller than b６ccs in all of 9 modes

Smaller than b６ccs in all of 9 modes

Theory : tends to positive shifts

Naïve average of all b ６ s modes

sin2eff = 0.52 ± 0.05 2.6 deviation

Naïve average of all b ６ s modes

sin2eff = 0.52 ± 0.05 2.6 deviation

Need more Data ! Need more Data !

4848

Decays w/ “Missing E(>2)”Decays w/ “Missing E(>2)”

B decay constant Lattice QCD

SM :

BSM : sensitive to New Physics from H

B B

4949

B : Exp. ChallengeB : Exp. Challenge

Y(4S)B- B+

+

N= 680keff.= 0.29% purity = 57%

N= 680keff.= 0.29% purity = 57%

Charged B

(*)0 (*)1/ / / SB D a D

0 0 0/D D sD

Tag-side: Full reconstruction

449M BB

Always > 2 neutrinos appear

in B decay

_

Majority : 1 track +invisible

5050

B : Candidate example B : Candidate example

Signature: Remove Tag-side

1 track + nothing

No extra trackEECL ~ 0

No extra trackEECL ~ 0

5151

B : Signal ExtractionB : Signal Extraction

Signal +background

Background

BSignal

EECL : extra neutral energy5 decay modes

Observe 17.2 events

significance = 3.5σ

+4.3 - 5.7

hep-ex/0604018submitted to PRL 449M BB

1st Evidence of B decay with > 2 !!

Big step for future in hunting NP

_

B (B+ ) = (1.79 ) x1040.39

0.460.560.49

5252

B :BaBarB :BaBar

BF(B++) = (0.88 0.11) x10-4

BR< 1.80 10-4 @ 90%CL

+0.68-0.67

Combined

(1.36 0.48)x10-4

Semi-lep tag only

_334M BB

fB = 0.216±0.022 GeV (HPQCD) PRL 95, 212001 (2005)

|Vub| = (4.39±0.33)×10-3 (HFAG)

fB = 0.200±0.038 GeV

[hep-ex/0608019]

5353

Constraints on H massConstraints on H mass

rH=1.130.51

Use known fB and |Vub |

Ratio to the SM BF.2

22

(1 tan )BH

H

mr

m

excluded

excl

uded

449M

5454

B K(*) : MotivationB K(*) : Motivation

b s with 2 neutrinos

SM: B(BK* ) ~1.3 x 10-5 B (BK ) ~4 x 10-6 (Buchalla, Hiller, Isidori)

PRD 63, 014015

DAMA NaI 3Region

CDMS 04

CDMS 05

No sensitivity in Direct search

• New Physics in Loop• Light Dark Mater (M~1GeV)

_

_

_

5555

B0 K*0 : ResultB0 K*0 : Result_

535M BB

Similar exp. technique as B

Full-rec. tag & K + nothingFull-rec. tag & K + nothing

3.12.64.7Yield

(1.7σ stat. significance)

Sideband = 19MC expectation = 18.73.3

460K tags

Hope to see Signal in (near?) Future

[hep-ex/0608047]

cf: BaBar B (B+K+ ) < 5.2 x 10-5

_ 85M BB

_

[PRL 94,101801(05)]

5656

SummarySummaryExcellent performance of B factories Belle + BaBar : > 1000 fb-1 data !

• CPV in B: KM-phase = source of CPV ~Established• CKM/SM Test: sin21: < 4% (1o) precision2, 3: 10~30o, |Vub| ~7% (~ in progress)• New Physics Searches

• CPV in b s penguin: sin21 <0 ? “2.6” • First Evidence of B decay with > 2

Milestone for Future NP search with • b s/d radiative/EW Penguins …

• LFV decays: reaching NP era : (lot more… not shown here)

• CPV in B: KM-phase = source of CPV ~Established• CKM/SM Test: sin21: < 4% (1o) precision2, 3: 10~30o, |Vub| ~7% (~ in progress)• New Physics Searches

• CPV in b s penguin: sin21 <0 ? “2.6” • First Evidence of B decay with > 2

Milestone for Future NP search with • b s/d radiative/EW Penguins …

• LFV decays: reaching NP era : (lot more… not shown here) The More data, lots of more New excitements !

_

5757

Future Prospects Future Prospects

2000 2002 200820062004 2010 201420120

2

4

6

8

10

Inte

grat

ed lu

min

osity

(ab

-1)

Calendar year

Belle is here. 0.63ab-1

Crab cavity installation

2 yr shutdown for upgrade

Lpeak~1.6×1034 1.6 - 3×1034SuperKEKB 4 - 8×1035

5B BB and every year

Super KEKB Proposed Schedule

[ ILC inspired Super B-factory (INFN/SLAC) Lpeak~1036]

5858

SuperKEKB: schematicsSuperKEKB: schematics

8 GeV e+ beam 4.1 A

3.5 GeV e beam 9.4 A

L ∝ I y

y*

(Super Quad)

Super Belle

4.5 x 5 0.45

~50

~8 x 1035 cm-2s-1

5959

Detector upgrade: baseline designDetector upgrade: baseline design

/ K

L d

etec

tio

nS

cin

till

ato

r st

rip

/til

e

Tracking + dE/dx small cell/fast-gas + larger radius

CsI(Tl) 16X0

Si vtx. det.

SC solenoid1.5T lower?

2 pixel lyrs. + 3 lyr. DSSD

pure CsI (endcap)

PID“TOP” + RICH

R&D inprogress

6060

Physics ReachPhysics Reach

SuperKEKB

5ab-1 50ab-1 LHCb

Physics at Super B Factory (hep-ex/0406071)

2fb-1

6161

Radiative & EW PenguinsRadiative & EW Penguins

EW

~1/100

Loops Sensitive to New Physics

Br, ACP ~SM

b s penguin

b sl+l penguin

b d penguin

l+

l

6262

b d Penguin : b db d Penguin : b d

Signals Established !

386M BB

37.2 signals

B++

B00

_347M BB

MES(GeV/c2)

LP05 5.5

Vtd/Vts

New Physics !

Vtd/Vts

New Physics !

[hep-ex/0607099]

[PRL96,221601(06)]

6363

b d Penguin : B KKb d Penguin : B KK

MES(GeV/c2)

37+9.68.3

23+6.55.4

5.3

6.0

d,u

b

d,us

s

W

g 0

0/

Vts/dVtb

t d Observation !Evidence

449M BB

_350M BB

[hep-ex/0608036] [hep-ex/0608049]

2004/5

5.3

7.3

6464

b s Penguin : EWb s Penguin : EWAFB(K*l+l ) of l+l AFB(K*l+l ) of l+l

K*B

J/ ’

[PRL 96, 251801(06)]386M BB

positive AFB

First Atempt Important step for future !

6565

Summary ofLFV decaysSummary ofLFV decays

6666

Effect of Penguin on 2Effect of Penguin on 2M. Gronau and D. London, PRL 65, 3381 (199

0)

)22sin(1 22 AS )22sin(1 22 AS

Isospin relation

EW Penguin neglected(isospin breaking)

6767

Belle 2006: B0→+− decay (tCPV)

04.010.061.0

05.008.055.0

S

A

first error: stat., second: syst.

background subtracted

+−

yie

lds

+−

asy

mm

etr

y

Large Direct CP violation (5.5)

Large mixing-induced CPV (5.6)

confidence level contour

1464±65 signal events

535M BB

[hep-ex/0608035]

22

6868

BaBar 2006: tCPV in B0 ６ BaBar 2006: tCPV in B0 ６

confidence level contour

Evidence for CP violation (3.6)

Direct CPV not yet observed

02.014.053.0

03.011.016.0

S

A

_347M BB

[hep-ex/0607106]

6969

History of B0→+− decay

2.3 diff. btw. Belle and BaBar

(C = A)

7070

2 constraints from B0→+− decay

inputsB(+0) = (5.75 0.42)B(+-) = (5.20 0.25) 10-6

B(00) = (1.30 0.21) A(00) = +0.35 0.33S(+-) = 0.59 0.09A(+-) = +0.39 0.07

inputsB(+0) = (5.75 0.42)B(+-) = (5.20 0.25) 10-6

B(00) = (1.30 0.21) A(00) = +0.35 0.33S(+-) = 0.59 0.09A(+-) = +0.39 0.07

No stringent constraintobtained with system alone need and

7171

2: B0 CPV2: B0 CPV

B(00) << B(+), B(+0) < 1.1 30 6 26 6 x10-6 (HFAG)

small Penguin effect () 2A00

A+0

A+-/ 2

fL ~ 100% CP +1

Similar to +, but more complicated …

Two lucky cards !

B VV: not CP eigenstate in general

+ +0: wide resonance

7272

B0 + tCPVB0 + tCPVB0 + : not CP eigenstate, same diagram as + Mixing CPV with 4 amplitudes (complicated)

B0 +0 : Dalitz[BaBar PRL 91,201802(’03); Belle PRL94,121801(’05)]

s =

m(

)

2

s+=m()2

A= fA+ fA+ fA

fi(s+, s) : form factors (Breit-Wigner)

A(ij) = Aij =ei2 T ij + P ij P = (P+P)/2

Fit to t, Dalitz dist. 2 w/o discrete ambiguity !

+

+

+

[Synyder, Quin, PRD48,2139(‘93)]

7373

2006: B ６ ( Dalitz analysis2006: B ６ ( Dalitz analysis

_347M BB449M BB

[2004 (16 parameters ignoring ) ]

[hep-ex/0608002][hep-ex/0609003]

1C

L

26 parameters fit (, , )

7474

2 Summary2 Summary

/2 = [93 ]+119

7575

Novel method: DalitzNovel method: Dalitz fCOM = D KS

B+:

B-:

m+=m(Ks+), m=m(Ks) CPV: Asymmetry in Dalitz dist.:

r

r |A2|

|A1|r =

2m

2m

0 D 2m

2m

0 D obtainfromtagged D0

(D*+ D0+)sample

Bondar, GGSZ [PRD 68,054018(’03)]

7676

CPV in Dalitz planeCPV in Dalitz planeMC simulation3 = 70 deg.= 0, r = 0.125

B+

B

1 2

34

Sensitivity to 3

7777

_347M BB

Belle: 53 3 9 (386M)+1518

[hep-ex/0607104]

3

rB

[PRD73,112009(06)]

B

B

7878

Comparison: Belle/BaBarComparison: Belle/BaBar

contours do not includeDalitz model errors

3

rB

DK+D*K+

B+

BB+

B

7979

3 Summary3 Summary

/3 = [71 ]+22

8080

b sqq decay modesb sqq decay modes--

SM expectation

“pure” b sss Golden mods

-

b sdd-

f+ = 0.91 0.07 [HFAG: Belle(isospin)+BaBar(moment)]

*

*

8181

SM ContaminationSM Contamination

+1KsKsKs

1Ks

P’

T

P

T’

Ks

Ks

f0Ks

Ks~+1K+KKs

CPmode

T’Pb

dg

t

d

ss

s

W

2P’

b

dg

t

d

ds

d

W

2T

W b

d

d

uu

s4 W

b

dd

u

u

ss

s

4

Tree (Vub) contamination

Long distance effect

1sin 2 0 within the SM Need to know the size to claim NP

4Im 0 at tsV O

2

2

2 4 3

2 5 2 4 2 61 12 2 8

2 3 5 2 4 12 2

1 2 8

1 2

1 1

A

A

A i

V A i A O

A i i A A i

u-quark penguin~Vub

* Vus

b

dg

d

ss

s

W

u

６ Positive sin21

8282

Flavor Tagging PerformanceFlavor Tagging Performance

(OF-SF)/(OF+SF)

~(1-2 w)cos(Δm t)

12 r-bins, 6 divisions in r. B0 and B0 tags treated separately.

_

B0 –B0 mixing_

Efficiency > 99.5%

effective = 28.7 0.5%

determined by data

B0 D*l

8383

Determination of UTDetermination of UT

1

2

3

Vtd Vtb

Vcd Vcb

Vud Vub*

*

*

B0 (cc)K(*)0

B0 D*+D(*)-(K)

-

B D(*)l b c l

B DCPK

B0 D(*)+

B l b u l

B ,

fB: B lB

b c(u)

Vcb,Vub W-

l-

l

(

((