C.C.Wang

2/

Flavor Physics & CP Violation2006/04/09

Chin-chi WangNational Taiwan University

C.C.Wang

Outline

� Introduction.

� What is

�

2

�� �

� Isospin analysis.

� Measurement of 2/

� from B factory.

� B0 �� �

� B0 �� �

� B0 �� � � 0

� � � � �

� Summary of 2/� measurement.

C.C.Wang

Introduction

C.C.Wang

Introduction

B0B0–

V V*

tbtd

Mixing

B0 ��������

0

2

B0

b–

du–

d–

��������*

Tree diagramu

B0 � � � ��

B0 � � � � �

B0 � � � � �

C.C.Wang

Isospin Analysis

12

A

���

A

� 0 � A

� 0

A00

12

A

��

A00�

A+-=A(B0 �� +� -/ + -)A+0=A(B+ �� +� 0/ + 0)A00=A(B0 �� 0� 0/ 0 0)

A+-=e2i

!3A(B0 �� +� -/ + -)

A+0=e2i!

3A(B- �� -� 0/ - 0)A00=e2i

!3A(B0 �� 0� 0/ 0 0)

""

"

_

_�=2( 2eff - 2)

Ignoring EWP

C.C.Wang

CPV measurement of B0 # $ # %

Prospects for 2/

& extraction:

' Good point

( all charged track )good backgrund suppression.' Bad (difficult) points( large branching fraction from B )* 0* 0

)large penguin contribution.

C.C.Wang

CPV measurement of B0 + ,.- /12

A

0�1

A

2 0 3 A

4 0

A00

12

A

5�6

A007

InputsBr(B+ 89 + :0)=(5.5 ;0.6) <10-6

Br(B0 => + ?-)=(5.0 @0.4) A10-6

Br(B0 BC 0 D0)=(1.5 E0.3) F10-6

A(B0 GH 0 I0)=+0.28 J0.4S(B0 KL + M-)=-0.50 N0.12A(B0 OP + Q-)=+0.37 R0.10

C.C.Wang

B0 S T.U V CPV measurement at Belle

High Quality region

MBC (GeV)

W

E (GeV)

Num

ber o

f eve

nts

4 X evidence of Direct CPV!

PRL 95, 101801 (2005)

S Y Y = -0.67 Z0.16 [0.06A \ \= +0.56 ]0.12 ^0.06

_` a bced f

C.C.Wang

B0 g h.i j CPV measurement at BaBar

No observation of CPV!

PRL 95, 151803 (2005)

S k k = -0.30 l0.17 m0.03C n n = -0.09 o0.15 p0.04

qr r steu v

C.C.Wang

B0 w x.y z Experimental Summary

S { {

-A | |(Cππ )

C.C.Wang

CPV measurement of B0 } ~�� �

Prospects for 2/

� extraction:

� Good point

� Small branching fraction of B0 �� 0 �0 (<1/20) compared with B0 �� �e� �− and B+ �� �e� 0�Small penguin contribution

� Bad (difficult) points

� two �0s are contained in the decay products�lower efficiency, larger BG

� Consists of three polarization states�polarization measurement is essential

C.C.Wang

CPV measurement of B0 � ��� �Inputs

Br(B+ �� + �0)=(26 �6)  10-6

Br(B0 ¡¢ + £-)=(26 ¤4) ¥10-6

Br(B0 ¦§ 0 ¨0)<1.1 ©10-6

A(B0 ª« 0 ¬0)=N.A.S(B0 ­® + ¯-)=-0.22 °0.22A(B0 ±² + ³-)=-0.02 ´0.17

12

A

µ�¶

A

· 0 ¸ A

¹ 0

A00

12

A

º�»

A00¼

small branching ratio of B0 ½¾ 0 ¿0

C.C.Wang

B0 À0 Á0 analysis at BaBar

ÂÃ Ã ÄÅÇÆ È

BR(B0 ÉÊ 0 Ë0) = (0.54 Ì0.19) Í10-6+0.36-0.32

ÎÏÐ ÑÒÔÓ ÕÖ Õ×Ø Õ ÙÚØ Ø Ò Û

UL<1.1 Ü10-6 90%C.L.

Ý Small branching ratio

Þ small penguin contribution.

ß good sensitivity for

à

2/

á extraction from B0 âã äæå ç

C.C.Wang

CPV measurement of B0 è é�ê ë

Longitudinal Transverse

1ì d 2 í

d cos

î

1 cos

ï

2

ð 94

14

1 ñ f L sin2 ò

1 sin2 ó

2

ô f L cos2 õ

1 cos2 ö

2

Three polarization of ÷ øúù û

C.C.Wang

B0 ü ý�þ ÿ CPV measurement at BaBar � � � �� � �� �� � � �� � �� � � �

CL(

� ��� �) = -0.03 �0.18 �0.09SL(

� ��� �) = -0.33 �0.24+0.08-0.14

fL(

!#" -) =0.978 $0.014 +0.021-0.029

%=100°±13° 79°< &<123°(95% C.L.)

C.C.Wang

B0 ' (*) + CPV measurement at Belle

,.- / , - 0 /

12 23 456 6 2 2 7 456

continuumb 8 cb 9 u

Helicity Mππ

signal

signal

continuum:; ;continuum

<= > ?@BA CDFE GIH E J K L M LN LO P

A = 0.00 Q0.30 R0.09S SL

T TL S = 0.08 U0.41 V0.09

fL =0.941 W0.030 +0.034-0.040 2=88°±17°

59°<

X

2<115°(95% C.L.)

C.C.Wang

Other B Y Y measurements

Br(B+ Z [*\ 0):31.7 7.1 /17.2 2.5 2.8+3.8-6.7

Br(B0 ] ^*_ -):24.4 2.2 /30 4 5+3.8-4.1

Belle/BaBar (×10-6)

fL:0.95 0.11 0.02/0.96 0.04 0.05

06 Moriond QCD

C.C.Wang

2

`ba summary of B0 c d*e f

C.C.Wang

CPV measurement of B0 g h i j kml npo qsr 0)

Prospects for 2/

t extraction:u Good pointv two scenarios by assuming isospin symmetry:w quasi-two-body approach.x direct measurement of

y

2/

z from Dalitz analysis.{ Bad (difficult) points of Dalitz analysis| complicated } ~�� ��� 0 resonant modes� higher resonance.� �� � mixing.� other resonance.� complicated backgrounds on Dalitz plot.

C.C.Wang

B0 �� ��� �

CPV measurement at Belle

� ��� � � �� �

���� � �� ¢¡ £ ¤

¥¦§©¨ ª« ¥¬ ­ ®¯ ° ±²³ ´²µ ¶·¸³ ¹ º» ¼ ½

¾¿ À ÁÂBà Ä

A ÅÇÆ È A

ÉÇÊ 2Ë A

Ì Í 2

A

ÎÇÏ 2 Ð A

Ñ Ò 2

Ó AÔ Õ Ö C× Ø Ù AÚ Û ÜCÝ Þ

1 ß àCá â ã Aä å Cæ ç èé 0.02ê 0.15 ë 0.02

ì 0.16 í 0.05

Aî ï ð A

ñ ò 2ó A

ôÇõ 2

A

ö ÷ 2 ø A

ùÇú 2

ûü Aý þ ÿ C� � � A �� �

C ��

1 � C � � A � C ��

� � 0.53 � 0.28 � 0.04

� 0.29 � 0.09

���� �� � �� ��! "$# ��! %&

PRL 94, 121801(2005)

C.C.Wang

B0 '( 0 )0 measurement from Belle

*+, -.0/ 1

Br(B0 23 0 40):(3.12 50.33 )10-6+0.88 -0.82

+0.50 -0.68

Acp= -0.53+0.67+0.10 -0.84 -0.15

hep-ex/0508007

C.C.Wang

B0 67 8:9 ; <>= ?0@ AB 0) CPV measurement at BaBar

CDE FG0H IJ$KL MKN O PQ PR P S S

A B0 TU VXW Y[Z 0 \ f ] A ^ _X` a b fc A d e[f g h f 0 A i 0 j 0

A B0 kl mXn o[p 0 q f r A s tXu v w fx A y z[{ | } f 0 A ~ 0 � 0

Time dependent Dalitz analysis by assuming isospin symmetry:

ρ �π �

ρ �π �

ρ

�

π

�

� ����� �� � A

��

cp = -0.088 �0.049 �0.013C �� = 0.34 �0.11 �0.05S �� =-0.10 �0.14 �0.04�

C �� = 0.15 �0.11 �0.03 S ¡¢ = 0.22 £0.15 ¤0.03

C.C.Wang

B0 ¥¦ §:¨ © ª>« ¬0­ ®¯ 0) CPV measurement at BaBar

C.C.Wang

B0 °± ²´³ µ ¶¸· ¹»º ¼¾½ 0) 2 from BaBar

¿ÀÁ ÂÃ0Ä Å

ÆÈÇ É

σ

Ê=(113 Ë6)°-17+27

A ÌÎÍ Ï A Ð ÑÒÓ ÔÕ 0.47Ö 0.15

× 0.14 Ø 0.06

AÙ Ú Û A ÜÎÝÞß àá 0.21 â 0.11 ã 0.04

C.C.Wang

Combined 2/

ä constraint

2=99

å+12-9

æ Note:

ç EWP is not included

è about 1~2

é

effect.

ê Isospin triangle for

ë ë does not close.

ì íî results still have some discrepancies.

C.C.Wang

Combined 2/

ï constraint

2

C.C.Wang

Prospects for 2

ðòñ measurement

ó Coming B ôõ öø÷ ù:ú 0 result from B factory.

û Improve the direct measurement of

ü

2

ýþ ÿ

� B �� � and B �� � with more data �

�

2 constraint from B0 �a1

� is possible

Br(B0� a1

�) (40.2 �3.9 �3.9) �10-6(Moriond QCD 06).

� Some other modes.

� K*0 �+, � � ��� etc......

C.C.Wang

Backup Slides

C.C.Wang

Introduction of Time-dependent Analysis

Flavor specified eigenstate

CP decay

8GeV e-

3.5 GeV e+

�

( 4S)

�z � ��� c

�

t

C.C.Wang

�- � mixing

Implement the !- " mixing form factor based on ALEPH and CMD-2 result.

# Implement the kinematic function.

F s $ BW % 770GS s

1 & '

BW ( 783GS s

1 ) * ) +

BW , 1450GS s -/. BW 0 1700

GS s

1 1 2 1/3BW M

GS s 4 M 2 1 5 d 6 7 8M

M 9 s : f s ; i s

<

s

C.C.Wang

KEKB and Belle

KEKB Co llide r

3.5 GeV e+ & 8 GeV e– beams3 km circumference, 11 mrad crossing angle

L= 1.63 x 1034 cm–2s–1 (world record)

L dt = 550 fb–1 @ (Υ 4S)+off(~10%)

C.C.Wang

PEPII and BaBar

e-

e+

=?> @AB CDEF GH IFJ GKLB CD EF G MJN C IL K MB F GF K O HP N Q

RF GFJ GL K L STE GF KE C I IVUWF S IFJ GF XN YF KF E ZL[ \ M D Y GO R T W N QR K M S G N Y CB ]F KO R N^ Q

_ M I MJ L E `F K GFaA K CJ ZF K O _ `A Q

TEb GKcB F E GF Xd Ica WF Gc KEO T d W Q

3.1 GeV e+ & 9 GeV e– beams

L= 1.00 x 1034 cm–2s–1 (Oct 9, 2005)

L dt = 335 fb–1 @ (Υ 4S)+off (~10%)

C.C.Wang

B0 e0 f0 Result

PRL 94, 181802 (2005)BR(B0 gh 0 i0 )=(1.17 j0.32 k0.10) l10-6

BaBar:

Acp = 0.12 m0.56 n0.06

PRL 94, 181803 (2005)

BR(B0 op 0 q0 )=(2.3 ) r10-6

Belle:

+0.4+0.2-0.5 -0.3

Acp = 0.44 s0.17+0.53-0.52

C.C.Wang

2/

t constraint from B0 u vxw y

C.C.Wang

B0 z{ |~} � ��� ��� ��� 0) 2 from BaBar

C.C.Wang

B0 a1

�

Br(B0� a1

�) � (40.2 �3.9 �3.9) �10-6

C.C.Wang

K*0 �+

� M/Beneke et al. hep-ph/0604005

� assuming SU(3) symmetry

� �=90 �7+2-5