Results from Belle and BaBar

P. Chang P. Chang HCP2005, 7 July HCP2005, 7 July B Factory ResultsB Factory Results

Results from Belle and BaBarResults from Belle and BaBar

Paoti ChangPaoti ChangNational Taiwan UniversityNational Taiwan University

Hadron Collider Physics Hadron Collider Physics Symposium 2005Symposium 2005

4-9 July 2005, Les Diablerets, Switzerland4-9 July 2005, Les Diablerets, Switzerland

HCP2005, 7 July

P. Chang B Factory Results

CP Violation and CKM Matrix

CPV in SM arises from an irreducible

complex phase.

Is there only one weak phase?

B meson properties

2

– Establish CPV in 2001 by Belle and BaBar

– Precise measurement of SM parameters

– Search for TCPV in other processes

– Direct CP violation and rare decay

HCP2005, 7 July


Asymmetric e eCollider

3

e+

(4S)

+

-

KS

J/B1

B2

+-

K+

-0

D

B0_

B0

t z c

z ~ 200m

fCP

Flavor tag

e

Piermaria Oddone

HCP2005, 7 July


B Factory Performance

Belle: Peak luminosity= 1.58 1034 cm s; ~ 1 fb/day

Unexpected

Shut down

BaBar: Peak luminosity~ 1 1034 cm-2 s-1

4

HCP2005, 7 July


BaBar Detector

Cherenkov Detector (DIRC)[144 quartz bars, 11000 PMTs]

Silicon Vertex Tracker (SVT)[5 layers]

Instrumented Flux Return (IFR) [Iron interleaved with RPCs].

CsI(Tl) Calorimeter (EMC)[6580 crystals].

Superconducting Coil (1.5T)

Drift Chamber [40 stereo lyrs](DCH)

e- (9 GeV)

e+ (3 GeV)

5

HCP2005, 7 July


Belle Detector

/ KL detection 14/15 lyr. RPC+Fe

CsI(Tl) 16X0

Aerogel Cherenkov cnt. n=1.015~1.030

Si vtx. det. 3/4 lyr. DSSD

TOF counter

SC solenoid1.5T

8GeV e

3.5GeV e

EFC

6

HCP2005, 7 July


Results Measurements on the unitarity triangle

– sin(2from b ccs

– sin(2eff from b sss

– and Rare Decays and Direct CP Violation – B → – Radiative B decays – Hadronic B decays See Abe and Forti’s talks @LP05 for Vub measureme

nts

and other results. 7

HCP2005, 7 July


Mixing Induced CP Violation

Asymmetry occurs due to the interference

between B0 → f and B0 → f.

Theoretically clean measurement

from J/S and other b →ccs decays.

Sf = sin2for JKS

8

HCP2005, 7 July


sin2/sin2 from B → J/ K0

034.0021.0

047.0668.0

A

S039.0049.0

069.0619.0

A

S

9

Nsig =5264 73 Nsig =4792 105

HCP2005, 7 July


sin2 sin Continue

New W.A. 0.687 0.032

• HFAG Winter 2005 average:

• Belle summer update (386 M BB pairs):

• HFAG New average (preliminary)

10

HCP2005, 7 July


Four-fold Ambiguity of 1

– sign ambiguity from the two choices of strong phases.

– BaBar resolves the ambiguity by examining the S wave and

p wave interference near K*0 (89 M BB).

– Belle assumes s-quark helicity conservation.

11

HCP2005, 7 July


Belle Extraction from B →D0h

12

HCP2005, 7 July


f(m,m) Determination

Using inclusive D*→D0

– Distinguish D from the sign

of slow

– Express f in sum of resonances

(18) and non-resonant amplitudes

– Perform unbinned likelihood fit

2 2

D0 → KS

13

HCP2005, 7 July


Time dependent Dalitz Analysis

Perform fit using 309 ± 31 events with 63% purity D(157 ± 24),D(67 ±10), D (58 ± 13), D*/D*

(27±11)

More K*+

Than K*

14

Belle Preliminary

HCP2005, 7 July


Dream of New Physics with CPV in Rare Decays

In the SM for the pure bs transition,

sin(2 1)eff (bsss) ≈ sin(2 1)(bccs)

Any large deviation may mean new physics. Decay Modes: B KS ;

B KS ;

B KKKS;KsKsKs

B f0 KS, KS, KS

Theoretically deviation

between the two processes

can be as low as ~ 5%.

15

HCP2005, 7 July


Results in last summer

sin21(bsqq) = 0.39 0.11 (Belle) 0.42 0.10 (BABAR)

CL = 1.2 104 (3.8)

World Average (WA)

sin21(bsqq)= 0.41 0.07 sin21(bccs) = 0.726 0.037

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HCP2005, 7 July


KS , KL and KKKS Signals

New

114±12

98± 18

399±28

17

180 16

78 13

536 29

HCP2005, 7 July


Fit Results of KS , KL and KKKS

18

HCP2005, 7 July


BaBar Measurement on KSKSKS

• Allow at most one KS →

• Find ZCP from the interception of three Ks tracks with IP constrained fit.

• Z resolution is dominated by tagged side vertex.

19

00 0

Nsig= 88 10

HCP2005, 7 July


Belle Measurements on KS and KL

20

Nsig =830 35 Nsig =187 18

BelleK0 :

“sin2”= 0.62 0.12 0.04C = 0.04 0.08 0.06

BaBarK0 :

“sin2”= 0.30 0.14 0.02C = 0.21 0.10 0.02

HCP2005, 7 July


B0f0KS

Measurements on KS, KS and f0KS

08.018.011.0

08.047.022.0

A

S13.039.019.0

53.095.0 12.015.0

A

S13.023.023.0

08.036.047.0

A

S

B0KSB0KS0

Belle update, 386 M BB pairs

21

Nsig = 344 ± 30

Nsig = 68 ± 13 Nsig = 145 ± 16

HCP2005, 7 July


Summary of b → s penguin results

22

Need super B factory to provide enough statistics.

2.6deviation

HCP2005, 7 July


extraction in B →

0

sin(2 )hh

hh

C

S

2eff

sin( )

1 sin(2 )

hh

hh hh

P T

C

S C

measure eff

need to bound |eff-| (shift from loops) different |Penguin/Tree| for different decays

:tdV

* :tdV

:ubV

+Loops (penguins)

23

HCP2005, 7 July


Isospin analysis

2| eff

|

Pure tree

A = A(B→h h)

A+0 = A(B→h+ h0) A00 = A(B→h0h0)

Gronau and London

h: or Why is better?

Br(B0 →00) is sizeable. not enough for A00 and Ã00

too large to set limit on

1. Br() is large. 2. almost fully long. polarized3. small non-resonant contr. 4. Br() is small.

The best way to extract() 2

4

HCP2005, 7 July


CPV on B0 →

hep-ex/050349, accepted by PRLBBM 232

B0 tags

B0 tags

Asymmetry

LP2005 Paper-180BB

M 275

B0 tags B0 tags

Poor tags Good tags

AsymmetryAsymmetry

25

HCP2005, 7 July


Isospin analysis for B→BABAR BELLE

fL

S,L

C,L

B

B

B__

67.54.5 10)8.55.22(

029.0033.0031.0039.0951.0

021.0029.0014.0978.0

08.014.024.033.0

08.042.009.0

09.018.003.0 09.010.030.000.0

68.37.6 10)1.77.31(

610)5430( 68.31.4 10)2.24.24(

6101.1

New

Use the averages of Belle and BaBar and the upper limit from BaBar (eff11O).

= 96o ± 13o

26

HCP2005, 7 July


)(96]CKM[ 1112-

Combine and

)(99]all[ 129-

27

HCP2005, 7 July


Extraction in DK Dalitz

color favored color suppressed

Select D0 → KS

32

2 2 2 2, ,if m m re f m m

32

2 2 2 2, ,if m m re f m m

BB[K[KSS]]DDKK

BB[K[KSS]]DDKK

m=m(KS)m=m(KS)

28

HCP2005, 7 July


Distributions of Dalitz Plots

29

HCP2005, 7 July


Results of Dalitz Analysis

30

HCP2005, 7 July


All constraints

Putting it together Angles only

No angles

31

HCP2005, 7 July


Search for B→

CKM fit predicts Br(B→) = (8.1 2.5) x10

Strategy:

1. Use hadronic tag or semi-leptonic tag2. 1 or 3 prong topology

3. Check EEcl for the remaining event.

C.L.%[email protected] 4 C.L.%[email protected] 4)Β( B

BBM 232 BB

M 275

32

HCP2005, 7 July


B→K(*) l+l, K

Clean probe for EW scale physics. K measurements:

same analysis method as

in analysis.

52

610BF BBM 89 BB

M 275

)Β( KB

100

36)Β( B

New

Belle LP05

33

HCP2005, 7 July


B→K(*) l+l

BaBar 227 M (NEW) Belle 275 M

Br(Kll) = 0.34 0.07 ± 0.03

Br(K*ll) = 0.78 0.12Br(Kll) = 0.550 ± 0.027

Br(K*ll) = 1.65 0.23 0.100.190.17

0.0750.070

Probing new physics on AFB of K*ll.

Stay tuned for EPS

34

HCP2005, 7 July


Search for →

SM prediction Br(B →) ~ 3 x10

Previous measurement: BaBar with 19.7 fbBr < 1.7 x 10

Belle new measurements

with 110 M BB:

Belle: Br <5.4 x 10 @ 90 C.L.

35

HCP2005, 7 July


CPV in B → KS *

LK

mixing

*RK

Helicity Flip Suppressed by ms/mb

0B

0B

2.00.19.0)(05.040.021.0)(

00

0*

SKSKS

BBM 232 LP Paper-97

*0

*0

0.01 0.52( ) 0.11( )

0.11 0.33( ) 0.09( )

K

K

S stat syst

A stat syst

0

0

0.08 0.41( ) 0.10( )

0.12 0.27( ) 0.10( )S

S

K

K

S stat syst

A stat syst

386 M Belle-conf-0569

Time dependent CPV is suppressed due to the correlation of photon helicity.

36

HCP2005, 7 July

P. Chang B Factory ResultsBB

M 211 hep-ex/0408034

2.1/

0.1

4.0

8.1

)BF(10Channel

0

-6

Search for b → d

1. Exclusive reconstruction

2. Simultaneous fit assuming

37

HCP2005, 7 July


Observation of b → d penguin

LP PAPER-155

5.5

2.6

5.1

1.5

)( Sign.

34.1/

58.0

17.1

55.0

)BF(10Channel

14.034.010.031.0

07.035.011.027.0

09.035.008.031.0

0

12.043.011.037.0

-6

BBM 386

0.143 < |Vtd/ Vts| <0.26038

HCP2005, 7 July


Another Evidence for b →d penguin

BaBar 227 M Belle 275 M

KSK+

KS KS

BaBar (10) Belle(10-6) B→KK

B→KK

B→KK

<0.6 <0.37 1.0 0.4

0.10.8 0.3 0.1

1.45 0.11

1.19 0.13

Preliminary

Preliminary

0.53 0.46

0.350.40

39

HCP2005, 7 July


Confirm Direct CP Violation

ACP(K+) = -0.133 0.030 0.009

ACP(K+) = -0.113 0.022 0.008

40

HCP2005, 7 July


Summary of Direct CPV in B→pp

WA ACP (K+

WA ACP (K+ ) ~ 3.9 deviation, why?

ACP sum rule (Gronau and Rosner): (K0) -1/2 (K+) + (K+0) = Ọ()

0.077 0.070 = Ọ(2 ) Iain Stewart

41

HCP2005, 7 July


New Resonance in e+e→ISRJ/

m = 4260 8 MeV = 88 23 MeV Include (2S) for

cross check

Missing mass distribution

consistent with

211 fb

42

HCP2005, 7 July


Summary

Precision measurements becomes a reality.

Deviation of “sin2” from b→s penguin is not settled.

Rare decays: sensitive to new physics

calibration1

29

– sin21 /sin2 = 0.6870.032 from b → ccs– 2/= (99 )o from , and. dominates.– D(*)K(*) Dailtz analysis. The best way to extract

12o <3/ < 137o (BaBar), 22o < < 113o (Belle)

Central values move closer; propose super B factory.

Observe b→d penguin; confirm Direct CPV; many fine measurements.

More results will be shown in EPS!

44

HCP2005, 7 July


Backup

HCP2005, 7 July


Current CPV results of B→

Belle 275M

BABAR 227M

~2.3 difference between Belle and BABAR

HCP2005, 7 July


Results from Belle and BaBar

Documents

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