cp violation and ckm angles status and prospects klaus honscheid ohio state university c2cr 2007

CP Violation and CKM Angles Status and Prospects

Klaus HonscheidOhio State University

C2CR 2007

K. Honscheid, Ohio State University, C2CR 2007

PEP-II at SLAC

KEKB at KEK

Belle

BaBar

9 GeV (e) 3.1 GeV (e+)peak luminosity:

1.21034cm2s1

Two asymmetric-energy B factories

8 GeV (e) 3.5 GeV (e+) peak luminosity:

1.71034cm2s111 nations, 77 institutes, ~600 persons

13 countries, 57 institutes, ~400 collaborators

The Two Asymmetric Energy B Factories


Experimental Landscape (early 2007)

0

200

400

600

800

1000

1200

1990 1992 1994 1996 1998 2000 2002 2004 2006

Tota

l In

tegra

ted L

um

inosi

ty (

fb-1)

CLEO IICLEO II.5

BaBar

Belle

710 fb-1

400 fb-1

Tevatron > 2.4 fb-1

# of B decays recorded

1.3 Billion

0.8 Billion

http://images.google.com/imgres?imgurl=http://w4.lns.cornell.edu/%7Ecdj/images/jpg/cleo.jpg&imgrefurl=http://w4.lns.cornell.edu/%7Ecdj/gallery.html&h=300&w=300&sz=17&tbnid=xuP9Acqyc-WBtM:&tbnh=111&tbnw=111&hl=en&start=1&prev=/images%3Fq%3Dcleo%2BII%2Bdetector%26svnum%3D10%26hl%3Den%26lr%3D%26sa%3DG

http://images.google.com/imgres?imgurl=http://www.spacedaily.com/images/antimatter-babar-bg.jpg&imgrefurl=http://www.spacedaily.com/news/physics-04v.html&h=160&w=200&sz=9&tbnid=B6Fnm14cVYBopM:&tbnh=79&tbnw=99&hl=en&start=10&prev=/images%3Fq%3Dbabar%2Bdetector%26svnum%3D10%26hl%3Den%26lr%3D%26sa%3DG

http://images.google.com/imgres?imgurl=http://www-he.scphys.kyoto-u.ac.jp/COVERPAGE/Belle.gif&imgrefurl=http://www-he.scphys.kyoto-u.ac.jp/dai2-he.html&h=260&w=262&sz=18&tbnid=xWnsAtYzp7tb4M:&tbnh=106&tbnw=107&hl=en&start=14&prev=/images%3Fq%3Dbelle%2Bdetector%26svnum%3D10%26hl%3Den%26lr%3D%26sa%3DG


CP( ) =

CP Violation in the Standard Model

CP Operator:

q

q’

J

g

q

q’

J

g*

Mirror

coupling

To incorporate CP violation

g ≠ g*

(coupling has to be complex)


CP Violation in the SM: The CKM Matrix

The CKM matrix Vij is unitary with 4 independent fundamental parameters

Unitarity constraint from 1st and 3rd columns: i V*

i3Vi1=0

β

-i

-i

γ1 1

1 1 1

1 1

e

e

CKM phases (in Wolfenstein convention)

u

d

t

c

bs

Vud Vus Vub

Vcd Vcs Vcb

Vtd Vts Vtb

arg[Vub*]arg[Vtd*]

112

11

2

11

23

22

32

AiA

A

iA


Interfering Amplitudes in Bo KDecays

B0 -+

B0 +-

A1 = a1 ei1 ei1

A1 = a1 e-i1 ei1

Asymmetry = = ~ 2 sin() sin(2)= 0

A2 = a2 ei2 ei2

A2 = a2 e-i2 ei2

+

+

|A|2 – |A|2

|A|2 + |A|2

(B) – (B)(B) + (B)

s

u

dd0B

KubV

*usV

b u

Tree decay

ubusVVA *

s

u

dd

0BKg

b

utcu ,,

Penguin decay

tbtsVVA *

Interference(A1+A2)2≠ (A1+A2)2


227 x 106 B0 Mesons

Count B0K+ Decays

227 x 106 B0 Mesons

Count B0K-+ Decays

Is N(B0K+ ) equal to N(B0K-+ )?

CP Violation in Bo K Decays

BABAR

background

subtracted

0

0

9

696

10

n B K

n B K

CP

Br B f Br B fA

Br B f Br B f


Golden mode B0J/Ks:CP eigenstate, high rate, theoretically clean

Mixing Induced CP violation

B0 J/Ks

ei0

ei0

No weak phase

B0ei2

Two Amplitudes Interference ACP ~ sin2

Two Vtd vertices ei2

+


(4S)

t =0

A Complication: Quantum CoherenceWe need to know the flavor of the B at a reference t=0 Flavor Tagging and measure the difference in decay time t Time Dependence

B 0

The two mesons oscillate coherently : at any given

time, if one is a B0 the other is necessarily a B0

In this example, the tag-side meson decays first.

It decays semi-leptonically and the charge of the

lepton gives the flavour of the tag-side meson :

l = B 0 l = B 0. Kaon tags also used.

tagB 0l (e-, -) =0.56

z = t c rec

sK

t picoseconds later, the B 0 (or perhaps its now a B 0) decays.

B 0

ll

d0B b

W

At t=0 we know this

meson is B0

Time dependent asymmetry ACP = SCPsin(mt)

CCPcos(mt) SCP = fCP sin2(fCP= ±1), CCP “direct” CP violation = 0 for

J/K


CP Violation in B0J/Ks

t for B0 tag B0J/K

t for B0 tag B0J/K

Background

BaBar preliminary, hep-ex/0607107

Belle preliminary, hep-ex/0608039

B0J/KSB0J/KL

BellePreliminary

BellePreliminary

B0 tags

B0 tagsB0 tags

B0 tags

t asymmetry

J/KL is fCP= +1

J/KS is fCP= 1

t oscillation

Period = B mixing m

Amplitude = D sin2(Dilution D due to mistags; measured experimentally)

PRL 98, 031802 (2007)PRL 98, 031802 (2007)


Extracting from sin2 has ambiguities; removed by J/K*, D*D*KS and D0//'/ analyses

Sin(2) World Average Heavy Flavors Averaging Group

E.Barberio et al., hep-ex/0603003

Statistics limited

Consistent with zero: no evidence for NP in tree decay

= 21.2o ± 1.0o


Is “” Universal?

)(/

/

,,)2(

/

000*0*

0

001

0

0

S

L

ScScS

S

KKKJ

KJ

KKKS

KJ

**0

*

,/

,

DDJ

DDDD

0

00

000000

00

)980(,

,,,

,,

SS

SSSS

S

KfK

KKKKK

KKKK

m)(charmoniu a) sccb

)charmonium (andcharm b) dccb

sssbsddb ,dominated-Penguin c)

Can use 3 different categories of B0 decays to measure :

golden mode

0K

0B

b

s

s

s

d d

Possible contribution from New Physics (NP): new

heavy particles in the loop

See the following talkby Tom Browder

News Flash

hep/ex 0702031

BD+D-

S = -1.12 ± 0.37 ± 0.09A = 0.91 ± 0.23 ± 0.06 (= -C)

(expected to be close to 0)


Let’s try this for the next angle: Access to from the interference of a b→u decay () with B0B0 mixing ()

d

d

0B

*tbV

tdV

b

b

0Bt

t

*tdV

tbV** // tdtbtdtb VVVVpq

B0B0 mixing

du

dd0B

ubV

*udV

b u

Tree decay

ubudVVA *

)cos()sin()( tmCtmStA dd

sin

)2sin(1 2

C

CS eff

ii

iii

eePT

eePTe

2

du

dd

0B

gb

utcu ,,

Penguin decay

tbtdVVA *

Inc. penguin contribution

0

)2sin(

C

S

222 iii eeeA

A

p

q

How can we obtain α from αeff ?

Time-dep. asymmetry :

NB : T = "tree" amplitude P = "penguin" amplitude


How to estimate |eff| : Isospin analysis

Gronau, London : PRL65, 3381 (1990)Gronau, London : PRL65, 3381 (1990)

)( 0 BAΑ

)( 00000 BAΑ

)( 00 BAΑ

2| eff

|

)(~ 0 BAΑ

)(~ 00000 BAΑ

Limiting factor in analysis


Measuring in B hep-ex/0607106

±0

0

0

0

6

572 53

(5.12 0.47 0.29) 10

0.019 0.088 0.014

N

BR

A

0 0

0 0

0 0

6

140 25

(1.48 0.26 0.12) 10

0.33 0.36 0.08

N

BR

C

0 0

°@90% C.L.

hep-ex/0608035

1464±65

S+- = -0.61 ± 0.1 ± 0.04A+- (=-C) = 0.55 ± 0.08 ± 0.05BR+- = (5.1±0.2±0.2) x 10-6

+-


Sometimes you have to be lucky

0.0150.013,

6

0.977 0.024

(23.5 2.2 4.1) 10

Lf

BR

615±57

0

0

0

6

0.0230.027,

(16.8 2.2 2.3) 10

0.905 0.042

0.12 0.13 0.10L

BR

f

A

390±49

0.05 0.070.19 0.21

0.07 0.15 0.06

S

C

0 0

0 0

0.37 60.36

0.110.13,

(1.16 2.7) 10

0.86 0.05L

BR

f

323198 22

•B is almost completely polarized

•B is small better constraint on

hep-ex/0607092hep-ex/0607097

hep-ex/0607098

B B B


Combining all methods:

Combined: = [93+11

9]

CL=0.683

Other solutions disfavoured

Global Fit = [ 98+5-19] º

Global fit without :


= arg[Vub*]: CP violation in DK modes

Relative phase = ei

B+

D0K+

ei

ei

V*ub vertex ei

E.g. B+D0 /D0K+

D0K+

D0/D0 CP state (GLW)D0/D0K+/K+, CA/DCS (ADS)D0/D0KS+, Dalitz (GGSZ)

D decays do not involve Vub or Vtd: no contribution to phase

GLW: Gronau, London, Wyler (2001)

ADS: Atwood, Dunietz, Soni (1997)

GGSZ: Giri, Grossman, Soffer, Zupan (2003)

ei

ei

B± DK: no time dependence; extract from rates and CP asymmetriesbut b u amplitude is small (for example rB (DK−) = 0.16 ± 0.05 ± 0.01 ± 0.05 Belle)


The GGSZ method – an example

BaBar preliminary; hep-ex/0607104

Belle; Phys.Rev.D 73, 172009 (2006)

Belle Belle

Map out Dalitz plot from all D0 Ks+- decays

B+B

Look for deviations in B±D0K± plots


Combined Result for

Indirect (CKM) = [59+94]

Combined: = [62+38

24 ]


The CKM Model has passed the experimental test

New TargetsEffects of TeV new physics deviations from SMLFV and new source of CPVHidden flavor symmetry and its breaking

[21.2 ± 1.0]o (0,0)

[93 +11-9]o

[62+38-24]o


The next few years (2007 – 2010)

• Belle and BaBar• 1 ab-1 (2006)• 2 ab-1 (2008)

• Tevatron• 2 fb-1 (2006)• 8 fb-1 (2009)

• LHCb is nearing completion

0

200

400

600

800

1000

1200

Ju

l-9

9

Ju

l-0

0

Ju

l-0

1

Ju

l-0

2

Ju

l-0

3

Ju

l-0

4

Ju

l-0

5

Ju

l-0

6

Ju

l-0

7

Ju

l-0

8

ICHEP08


LHCb Prospects (Some of the things they can do)

Bs Mixing phase (s) using Bs J/Signal yield: 130k events per L=2fb-1 with a B/S0.1, Sensitivity s ~ 0.021Sensitive probe of New Physics effects in the Bs mixing

s = s(SM) + s(NP) with s(SM)=-22 ~ -0.037±0.002

0,0

0,2

0,4

0,6

0,8

2006 2008 2010 20140,00

0,01

0,02

0,03

0,04

2006 2008 2010 2014

now

pre-LHCbLHCb atL=2fb-1

LHCb at L=10fb-1

year

( s

)

year

now pre-LHCbLHCb atL=2fb-1

LHCb at L=10fb-1(

s)

Sensitivity to Standard methodsGolden Mode Bs DsK

Sensitivity ~ 4.2o with 2 fb-

1

0

4

8

12

16

20

2006 2008 2010 2014

()

[o]

now

pre-LHCbwith LHCbat L=2fb-1 with LHCb

at L=10fb-1

year

V. Vagnoni CKM2006


%7.4/)(

%17/)(

Summer 2006

From B-Factories to LHCb – without new physics

%3.3/)(

%4.7/)(

2008* LHCbLHCb

L=10 fb L=10 fb-1-1

%8.1/)(

%6.3/)(

2014


Super B-Factory Plans at KEK and Frascati

Interaction RegionCrab crossing

=30mrad.y*=3mm

New QCS

Linac upgrade

More RF power

Damping ring

New Beam pipe

L = 81035/cm2 /sec

Design Luminosity ~ 1 x 1036 /cm2/secSynergy with ILCRecycle components (PEP, BaBar)Lots of R&D needed

KEK Frascati

IP

ILC ring ILC FF


SummaryCKM Model is now a tested theory

Great success for theoristGreat success for experimentalistGreat success for the Standard Model = (93+11

-9)o

= (21.2 ± 1.0)o

= (62+38-24)o

Search for Deviations from SM and New PhysicsNear Term Future Looks Promising

B Factories only half way doneTevatron will triple data sampleLHC(b) turn on

Long Term ProspectsLHC(b) upgradesSuper B Factories (KEK, INFN)

cp violation and ckm angles status and prospects klaus honscheid ohio state university c2cr 2007

Documents

b decays

b mixing

t s cp

mesons count b

hepex0608039 b

golden mode b

s cp sin

cp eigenstate