CP VIOLATION at B-factories

35
CP VIOLATION at B-factories A.Bondar (Budker INP,Novosibirsk) Measurements of large CPV in bc c s modes Search for New Physics: CPV in bs penguin modes Measurement of CPV in B + See also Today A.Mihalyi “Recent results on the CKM angle α from BABAR” New method of the measurement in BD 0 K based on Dalitz plot analysis of the three body D 0 K S + decay See also Today M. Legendre Status and prospects for the measurement of angle γ ” T. Gershon “Measurement of φ 3 using B– to DK– with D to K s π+π–” DANE04 Frascati June 7, 2004

description

CP VIOLATION at B-factories. A.Bondar (Budker INP,Novosibirsk). Measurements of large CPV in b c c s modes Search for New Physics: CPV in bs penguin modes Measurement of CPV in B p + p – See also Today A.Mihalyi “ Recent results on the CKM angle α from BABAR ” - PowerPoint PPT Presentation

Transcript of CP VIOLATION at B-factories

Page 1: CP VIOLATION at B-factories

CP VIOLATION at B-factoriesA.Bondar (Budker INP,Novosibirsk)

Measurements of large CPV in bc c s modes

Search for New Physics: CPV in bs penguin modes

Measurement of CPV in B+–

See also Today A.Mihalyi “Recent results on the CKM angle α from BABAR”

New method of the measurement in BD0K based on Dalitz plot analysis of the three body D0KS+–decay

See also Today M. Legendre “Status and prospects for the measurement of angle γ ”

T. Gershon “Measurement of φ3 using B– to DK– with D to Ks π+π–”

DANE04 Frascati June 7, 2004

Page 2: CP VIOLATION at B-factories

Coupling strength at decay vertex : gFVij

universal Fermi weak coupling : gF

Vij : quark-mixing matrix elements

CKM matrix : unitarity : Vji*Vjk=ik explicit parametrization (Wolfenstein) complex phase leads to different bu and td amplit

udes for quarks and anti-quarks.

V Vud Vus Vub

Vcd Vcs Vcb

Vtd Vts Vtb

1 2 2 3A i 1 2 2 2A

3A 1 i 2A 1

(4 )

CP0.2235±0.0033 A 0.81±0.08 |i| 0.36±0.09 |i| 0.79±0.19

The Weak Decays of Quarks

quark decay

gFVijij

W

quark decay

gFVij*i

j

W

DANE04 Frascati June 7, 2004

Page 3: CP VIOLATION at B-factories

The Unitarity Triangle

Using orthogonality relation

* *ub ud tb td* *cb cd c

* * *ub ud cb cd tb td

b cd

V V V V

V V V V

V V V V V Vi k :=1, = + + =0

+ 1

3

+ = 0

B0 B0

B0 D(*)B+ DK

B0 J/Ks

B0 Ks

B0 D(*)D(*)

*ub ud*cb cd

V V

V V

*tb td*cb cd

V V

V V

DANE04 Frascati June 7, 2004

Page 4: CP VIOLATION at B-factories

CKM CP phenomenology

CP violation arises from the interference of two amplitudes with different phases.

Mixing induced CP violation : Indirect CPV Decay amplitudes asymmetry: Direct CPV

Single CKM phase = unique source of CPV ? It is difficult for CKM CPV to explain the observed

matter/antimatter asymmetry in the universe. It is needed to search for Beyond SM !

DANE04 Frascati June 7, 2004

Page 5: CP VIOLATION at B-factories

)}]sin(

)cos({1[);(/||

tmS

tmAe

tfBPBt

CP

Time-dependent CP violation

If either S or is non-zero, B fCP has CP asymmetry.If either S or is non-zero, B fCP has CP asymmetry.

0

0

0

0

CP CPf

B

BB f

B

CPfA

CPfA

CPfA

CPfAmixing mixing

decay decay

0 0q = 1 = ( ) for tag-side B B

Mixing induced CPV param.

Direct CP violation param.

DANE04 Frascati June 7, 2004

Page 6: CP VIOLATION at B-factories

KEKB & BELLEBELLE detector

KEKB Collider

~350 scientists, 55 institutions3.5GeV e+ & 8GeV e Asymmetric Collider3km circumference, 11mrad crossing angleL= 1.3 x 1034 cm–2s–1 (world record)Ldt = 266 fb–1 @{Y(4S)+off(~10%)}

(140fb1 : 1.52 x 108 )

BB pairs

DANE04 Frascati June 7, 2004

Page 7: CP VIOLATION at B-factories

PEPII & BABAR

BABAR Detector

PEPII Collider

3GeV e+ & 9GeV e Asymmetric Collider

L= 0.92 x 1034 cm–2s–1 Ldt = 214 fb–1 @{Y(4S)+off(~10%)}

Cherenkov Detector (DIRC)

Silicon Vertex Tracker

Instrumented Flux Return

CsI(Tl) Calorimeter

Superconducting Coil (1.5T)

Drift Chamber

e- (9 GeV)

e+ (3 GeV)

DANE04 Frascati June 7, 2004

Page 8: CP VIOLATION at B-factories

e e+e: 8.0 GeVe+: 3.5 GeV

BCP

z

Btag

(4S) ~ 0.425

fCPfCP

z cB ~ 200 m

Flavor tagFlavor tag

4 steps toward the CP violation measurement

• Reconstruct B fCP decays

• Determine the flavor of Btag • Measure proper-time interval : t • Evaluate asymmetry from the obtained t

distributions

How to measure CP violation ?

DANE04 Frascati June 7, 2004

Page 9: CP VIOLATION at B-factories

tags)(poor

tags) (good

DCPV No 0.0411.007 ||

0.0280.0570.733sin2

scc

1

06.073.02sin 1

13.080.02sin 1

hep-ex/0308036

0.0490.736)2WA2003(sin

tmeasuremen precision a becoming Now

1

sin21 : bbccsccs BB140 fb ~152M pairs- 1

BaBar 81 fb-1: sin(2φ1) =0.741±0.067±0.033

DANE04 Frascati June 7, 2004

Page 10: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

cos21 from B

J/J/

Moriond04,

M.Verderi

Page 11: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

cos21 from B

J/J/

Page 12: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

cos21 from B

J/J/

Page 13: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

Non-Standard-Model particles could appear in the

penguin loop, modifying rate and/or CP asymmetry

Non-Standard-Model particles could appear in the

penguin loop, modifying rate and/or CP asymmetry

In the SM, for pure bs penguin transition modes sin21eff = sin21(BJ/KS)

Page 14: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

L = 108 fb-1L = 108 fb-1hep-ex/0406005

Page 15: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

L = 111 fb-

1

L = 111 fb-

1

BELLE PRD 60, 012001(2004)

hep-ex/0406005

Page 16: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

sin21 Summary

Page 17: CP VIOLATION at B-factories

Points of B0 π+π–

decay sensitive to CKM angle 2

direct CP violation may also occur because of interference between

b u tree amplitude and

b d penguin amplitude

It’s very important to check the KM matrix by other measurements.

b ud

B0 dW+

d

B0b

dB0

duud

gt

0 = = (1)Amp( ) = T + P tb td*

ub ud

*V VbO

a V VB a b

DANE04 Frascati June 7, 2004

Page 18: CP VIOLATION at B-factories

)(

)(

0

0

3

3

2

3

3

|/|1

|/|1

),||)|(|)(

),||)|(|)(

i

ii

iii

iii

eTP

eTPe

ePeeTBA

ePeeTBAPT

PT

221

21

12

212

|/|cos)cos(|/|21

,/]sin)sin(|/|2[

,/]2sin|/|

cos)sin(|/|22[sin

TPTPR

RTPA

RTP

TPS

TP

Constraints on the CKM angle 2

4 parameters

|P/T| 0.15-0.45 (representative) Theory ~0.31 23.7 deg (Belle & BaBar combined)

Strong phasedifference

convention taken fromM.Gronau and J.L.RosnerPhys. Rev. D65, 093012 (2002)

DANE04 Frascati June 7, 2004

Page 19: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

sin22 : bbuuduud , B0

High Quality Events

Low Quality Events

L = 140 fb-1L = 140 fb-1

Page 20: CP VIOLATION at B-factories

S

A

Significance

Feldman-Cousins Analysis

(5.2 Observation of CP violation

3.2 for A=0 and any S

Evidence for direct CP violation

3.3 for “superweak” case

hep-ex/0401029

DANE04 Frascati June 7, 2004

Page 21: CP VIOLATION at B-factories

History of A and S

Belle

BaBarThis resultBelle 140fb1

Difference still at ~2.0 levelDANE04 Frascati June 7, 2004

Page 22: CP VIOLATION at B-factories

Constraint on 2 and |P/T|

Belle140fb1

12

3

|P/T| > 0.17[95.5% C.L. (2)]

2 (

deg.

) (deg.)

2 (

deg.

)321

90 ≤ 2 ≤ 146 (95.5% CL) |P/T| =0.3

|P/T|

|P|/(|T|+|P|)

DANE04 Frascati June 7, 2004

Page 23: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

sin22 : bbuuduud , B0

Page 24: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

measurement, BDD(*)0(*)0KK

Page 25: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

measurement, BDD(*)0(*)0KK

ρ-ω interference

Doubly Cabibbosuppressed K*

Construct f as sum of known two-body resonances plus non-resonant term, fit to continuum D*-to-D-to-Kππ data.

Page 26: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

measurement, BDD(*)0(*)0KK

L = 140 fb-1L = 140 fb-1

73 events 73 events

Page 27: CP VIOLATION at B-factories

B+ D(*)0K+ fit result

r+=0.40±0.15, θ+=256±19°

r- =0.21±0.15, θ- = 71±37°

B+ D0K+ B+ D*0K+

r+=0.29±0.19, θ+=353±38°

r- =0.38±0.19, θ- =249±32°

DANE04 Frascati June 7, 2004

Page 28: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

measurement, BDD(*)0(*)0KK

Combined fit:

Page 29: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

Conclusion

Belle and BaBar continue to refine their measurements of from ccs

modes.

Belle and BaBar continue to refine their measurements of from ccs

modes.

__

Both experiments are using their high-luminosity data samples to probe for new physics in rare B decays: over-constrain the sides

and angles of the Unitarity Triangle.  

Both experiments are using their high-luminosity data samples to probe for new physics in rare B decays: over-constrain the sides

and angles of the Unitarity Triangle.  

todaytoday this summerthis summer in two years?in two years??

140fb-1140fb-1 270fb-1270fb-1 >500fb-1>500fb-1

Page 30: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

Conclusion

Many new/updated results utilizing ~230–280 fb-1 of data per experiment will be shown

this summer.

Watch this space!

Page 31: CP VIOLATION at B-factories

CP eigenstates

category CP mode process CP(f) SM prediction

S A Penguin

charmonium

J/ KS f sin21 0 negligibl

e(2S) KS

C1 KS

C KS

J/ K*(KS0)

J/ KL

charmonium

J/ 0 f sin21eff yes

double charm

D(*)D(*) small yes

bs penguin

KS f sin21 small dominan

t’ KS

K+KKS

hh f sin22eff yes

b ccs

b ccd

b uud

b sqq

(f CP eigenvalue)

0

0

DANE04 Frascati June 7, 2004

Page 32: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

Continuous Injection

Page 33: CP VIOLATION at B-factories

sin22 : bbuuduud

Time-dependent CP asymmetries in B0 π+π– -- the best way to access the CKM angle 2

0

0

| |/

( ) [1 { sin( )

cos( )}]

Bt

qd

d

eP t q S m t

A m t

2

2 2

2

1 2, ,

1 1

( )

( )M

i

ImA S

A B fe

A B f

= +1 for B0 tag 1 for B0 tag

direct CP asymmetry

t=z/(c)

DANE04 Frascati June 7, 2004

Page 34: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

sin22 : bbuuduud , B0

Page 35: CP VIOLATION at B-factories

DANE04 Frascati June 7, 2004

sin22 : bbuuduud , B0

L = 113 fb-1L = 113 fb-1