Measuring the apex: |V ub |, |V cb | and their relative phase γ ( φ 3 )

46
ICHEP '06 Kowalewski 1 ub ub cb cb their their relative phase relative phase γ γ ( ( φ φ 3 3 ) ) Р. Ковалевски R. Kowalewski U. of Victoria Canada γ γ | | V V cb cb | | | | V V ub ub | | * * cb cd ub ud V V V V

description

Measuring the apex: |V ub |, |V cb | and their relative phase γ ( φ 3 ). Р . Ковалевски R. Kowalewski U. of Victoria Canada. γ. |V ub |. |V cb |. η. β. ρ. Motivation. V ub is a key element of the CKM matrix - PowerPoint PPT Presentation

Transcript of Measuring the apex: |V ub |, |V cb | and their relative phase γ ( φ 3 )

Page 1: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 1

Measuring the apex:Measuring the apex:|V|Vubub|, |V|, |Vcbcb| and their | and their

relative phase relative phase γγ ( (φφ33))

Р. КовалевскиR. KowalewskiU. of Victoria

Canada

γγ

|V|Vcbcb|||V|Vubub||

*

*

cbcd

ubud

VV

VV

Page 2: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 2

MotivationMotivation Vub is a key element of the CKM matrix

1 graduate student lifetime (~20 years) ago, we didn’t know that Vub ≠ 0:Was the KM mechanism for CP viable?

Now the precise determination of Vub / Vcb provides a benchmark for testing new physics in other processes

tbtsi

td

cbcscd

iubusud

VVeV

VVV

eVVV

β

cb

ub

V

V

η

ρ

UTFitFPCP 2006

Page 3: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 3

Big trees dominate!Big trees dominate!

The decay channels used to study |Vub|, |Vcb| and their relative phase are all dominated by tree diagrams

b

q c, u

ν

D0

K-

K-

D0q

Interference allowsphase measurement

Lifetime + semileptonic decay determine |Vqb|

“f”

B

B-

B-

Vq

b

Vcb

Vu

b

Page 4: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 4

The magnitudes|Vcb| and |Vub|

tbtsi

td

cbcscd

iubusud

VVeV

VVV

eVVV

Page 5: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 5

Semileptonic B decay - Semileptonic B decay - theorytheory Large BF, only one hadronic current

Inclusive decays b qℓν: Weak quark decay + QCD

corrections OPE in s and 1/mb

Exclusive decays B Xℓν: Form factors: need Lattice QCD

Vqb

|Vcb

| and |

Vu

b|

from

sem

ilep

tonic

B

deca

ys

These inclusive and exclusive determinations

of Vqb are complementary

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ICHEP '06 Kowalewski 6

Semileptonic B decay - Semileptonic B decay - experimentexperiment Inclusive decays b qℓν:

Measure lepton Measure pmiss or associated hadrons

Exclusive decays B Xqℓν: Measure lepton and specified hadrons

Measurements come from Y(4S)BB

Determine non-B contribution using data below BB threshold

BB

qq

Vqb

|Vcb

| and |

Vu

b|

from

sem

ilep

tonic

B

deca

ys

Page 7: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 7

Inclusive |Vcb|

tbtsi

td

cbcscd

iubusud

VVeV

VVV

eVVV

See talk of Urquijo, S10

Page 8: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 8

Total decay width for b cℓν:

Similar expressions for b uℓν, b sγ

Comparison with data relies on quark-hadron duality

integrate over “broad” regions of phase space

Inclusive decay widthInclusive decay width

...

m

ρ,

m

ρr,z

m

μ,

m

μr,z

m

0rzμr,AA1

192π

mGVΓ

3b

3LS

3b

3D

32b

2G

2b

2b

0pert

ew3

5b

2F2

cb

free quark decay

Perturbative corrections

Non-perturbative power corrections

~1.014 ~0.908

|Vcb

| fr

om

in

clusi

ve

deca

ys

r = mc / mb

Low-order moments can be calculated reliably

Page 9: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 9

Global fit for |VGlobal fit for |Vcbcb|, m|, mbb… … Fit predicted moments of inclusive processes bcℓν and bsγ

for various cuts on kinematic variables:

Calculations available in “kinetic” and “1S” renormalization schemes

47 measured moments used from DELPHI, CLEO, BABAR, BELLE, CDF (and, of course, the B lifetime)

),,,,,,( 33220

00LSDGcb

xnE

nXBEE

nx mmEfdMM

l

b-b-quark quark massmass

e or e or γγ energy energy

cutcutc-c-quark quark massmass

Matrix elements Matrix elements appearing at appearing at order 1/morder 1/mbb

22 and and 1/m1/mbb

33

|Vcb

| fr

om

in

clusi

ve

deca

ys

Benson, Bigi, Gambino, Mannel, Uraltsev

(several papers)

Bauer, Ligeti, Luke, Manohar, TrottPRD 70:094017 (2004)

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ICHEP '06 Kowalewski 10

|Vcb

| fr

om

in

clusi

ve

deca

ys

mb (GeV)

μ π2 (

GeV

2)

bsγ

bcℓν

combined

kinetic scheme

χ2 / Ndof = 19.3/44

1S scheme

χ2 / Ndof = 5.7/17

Global fit: resultsGlobal fit: results

|Vcb| determined to <2%

Only sinθc known better!

|Vcb| (10-3) 41.96 ± 0.23exp± 0.35HQE± 0.59ΓSL

mb [kin]

(GeV)

4.59 ± 0.025exp± 0.030HQE

μπ2

[kin]

(GeV2)

0.401 ± 0.019exp± 0.035HQE

[kin]/[1S] values agree after

scheme translation

Buchmüller and Flächer,PRD 73: 073008 (2006) |Vcb| (10-3) 42.0±0.7fit±0.5αs

±0.6th

|Vcb| (10-3) 41.5 ± 0.5fit ± 0.2τB

mb[1S]

(GeV)

4.73 ± 0.05fit

λ1[1S](GeV2) -0.30 ± 0.04fit

mb to 1%; crucial for |Vub|

New!

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ICHEP '06 Kowalewski 11

Inclusive |Vub|

tbtsi

td

cbcscd

iubusud

VVeV

VVV

eVVV

See talks of Dubitzky, Schwanda, S10

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ICHEP '06 Kowalewski 12

Background bcℓν rate is 50 times signal Restrict kinematics to suppress background: challenge for

theory OPE convergence is compromised:

Need light-cone distribution (shape) function of b quark Relate buℓν directly to bsγ (e.g. Lange, Neubert, Paz, JHEP 0510:084,

2005)

Measure bu rate in regions dominated by bc Theory fine; must fight large

uncertainties from background

Strategies for isolating Strategies for isolating bbuuℓℓνν decays decays

|Vu

b|

from

in

clusi

ve

deca

ys

In all cases sensitivity to mb

N, N»5

q2 (

GeV

2)

Ee (GeV)

bc allowed

Points are buℓν simulation

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ICHEP '06 Kowalewski 13

Shape functionShape function bsγ spectrum measured by CLEO, Belle, BaBar

SF moments related to HQE parameters

Subleading shape functionsdiffer in bsγ, buℓν

hep-ex/0607071preliminary

Spectrum in lepton tagged

events

|Vu

b|

from

in

clusi

ve

deca

ys

2

γ2b

γ μEE ,2

mE

γ

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ICHEP '06 Kowalewski 14

New measurementsNew measurementsBaBar result: PRL 96:221801 (2006)

Fully reconstruct 1 B meson; study semileptonic decay of other B

|Vub|=(4.43 ±0.38 ±0.25 ±0.29) 10-3

Measure up to mX < 2.5 GeV |Vub|=(3.84 ±0.70 ±0.30 ±0.10) 10-3

|Vu

b|

from

in

clusi

ve

deca

ys

CLEO limit Weak Annihilation contributions: ΓWA / Γbu < 7.4% (90% CL) PRL 96:121801 (2006)

2/

min0 min

max

, to RelateBm

E

sbm

XX

ub dEEEWdE

ddm

dm

d

bu

e+

νIsoscalar hadron

Theory errors are small

Will improve – only 88×106 BB used so far

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ICHEP '06 Kowalewski 15

Theory calculationsTheory calculations

Two sets of calculations in use for b sγ and b uℓν

Bosch, Lange, Neubert, Paz (BLNP): 3-scale OPE based on HQET, SCET

Andersen, Gardi (DGE): parton-level calculation, only mb and ΛQCD input

Both provide good description of data; give similar results

Bauer, Ligeti, Luke (BLL): |Vub| using mX-q2 cuts

|Vu

b|

from

in

clusi

ve

deca

ys

PRD 72:073006 (2005)

JHEP 0601:097 (2006)

PRD 64:113004 (2001)

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ICHEP '06 Kowalewski 16

Determination of |VDetermination of |Vubub||

Good C.L. = 41% Error budget (in %; total 7.3) :

±2.2stat ±2.8exp ±1.9WA ±1.9b2c model ±1.6b2u model ±4.2HQ param ±3.8sub SF

DGE: (4.46±0.20±0.20)×10-3

C.L. = 12% BLL mX-q2: (5.02±0.26±0.37)×10-3

C.L. = 77% Many measurements use small

fraction of current data samples. Aggressive target for 2008 is 5%

|Vu

b|

from

in

clusi

ve

deca

ys

~ exp

~ theory

|Vub| = (4.49±0.19±0.27)×10-3 (BLNP)

Major progress since last ICHEP

Page 17: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 17

Exclusive |Vcb|

tbtsi

td

cbcscd

iubusud

VVeV

VVV

eVVV

See talk of Lopes Pegna, S10

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ICHEP '06 Kowalewski 18

Exclusive bExclusive bccℓℓνν decaysdecays Heavy-to-heavy transition; HQ symmetry applies

unique, universal FF, unit normalization at zero recoil

b ceν

before after

Light d.o.f. unchanged!

wwVG

dw

DBd cbF GF48

2

3

22*

phase space

form factors

D* boost in the B rest frame

1.504 1 ;2 *

22*

2

wmm

qmmw

DB

DB

|Vcb

| fr

om

excl

usi

ve d

eca

ys

Page 19: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 19

BBDD**ℓℓνν form factor form factor 3 non-trivial form factors; 4 observables:

w and 3 angles HQET-params:

ρ2 = -dF/dw |w=1 , R1 ~ V/A1 and R2 ~ A2/A1

Two measurements from BaBar; averaged values:

ρ2 = 1.179 ± 0.048 ± 0.028 R1 = 1.417 ± 0.061 ± 0.044R2 = 0.836 ± 0.037 ± 0.022

F(1)|Vcb| = (34.68 ± 0.32 ± 1.15)×10-3 BF(B0D*+ℓ-ν) = 4.84 ± 0.39%

|Vcb

| fr

om

excl

usi

ve d

eca

ys

BaBarhep-ex/

0607076preliminary

pℓ (GeV)

BaBar hep-ex/0602023

w

Page 20: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 20

|V|Vcbcb| from B| from BDD(*)(*)ℓℓνν

New HFAG average including updated form-factorsF(1)|Vcb| = (36.2 ± 0.8)×10-3

Using

(Quenched LQCD, PRD 66:014503 (2002))

Work needed on both experiment and theory to reach the precisionof the inclusive determination

Similar measurements on BDℓ-ν are harder; in progress

|Vcb

| fr

om

excl

usi

ve d

eca

ys

030.0035.0919.01

F

31.561.24cb 100.8739.4V

(inclusive: |Vcb|=(42.0±0.7)×10-

3

Page 21: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 21

Exclusive |Vub|

tbtsi

td

cbcscd

iubusud

VVeV

VVV

eVVV

See talks of Dubitzky, Schwanda, S10

Page 22: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 22

B B ππℓℓνν New BaBar B0 π -ℓ+ν

High statistics ν-reco method Significantly improved

precision ISGW2 model: C.L. = 0.07% Data consistent with Lattice

QCD and Becirevic-Kaidalov

0.040.050.53α

100.030.040.37GeV 16qΔBF

100.100.081.44νπBBF

BK

422

4

|V

ub|

from

excl

usi

ve d

eca

ys

4

422

4

100.380.382.91νBBF

100.050.080.40GeV 16qΔBF

100.130.161.37νπBBF

New CLEO B0 π -/ρ- ℓ+ν preliminary Good quality ν-reco

hep-ex/0607060

q2

CLEO preliminary

mπℓν

All q2 combined

Page 23: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 23

B B ππℓℓνν with low with low backgroundbackground Reconstruct (tag) one B in

hadronic or semileptonic decay

Compare what’s left with signalBaBar 211 fb-1

Belle 253 fb-1

BF (10-4) Belle hep-ex/0604024 BaBar hep-ex/0607089

π+ℓν (s.l. tag) 1.38 ± 0.19 ± 0.14 1.12 ± 0.25 ± 0.10

π0ℓν (s.l. tag) x2τ0/τ+1.43 ± 0.26 ± 0.16 1.35 ± 0.33 ± 0.19

π+ℓν (had tag) 1.49 ± 0.26 ± 0.06 1.07 ± 0.27 ± 0.19

π0ℓν (had tag) x2τ0/τ+

1.60 ± 0.32 ± 0.11 1.52 ± 0.41 ± 0.20

ρ0ℓν / ηℓν 1.33 ± 0.23 ± 0.18 0.84±0.27±0.21

ρ+ℓν / η’ℓν 2.17 ± 0.54 ± 0.32 <1.3

|Vu

b|

from

excl

usi

ve d

eca

ys

Hadronic tag

Preliminary

π+ℓν π0ℓν

ρ+ℓν π+ℓν

π0ℓν ρ0ℓν

Semileptonic tag

Page 24: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 24

(inclusive: |Vub|=(4.49±0.34)×10-3

Experimental error on |Vub|

~ 6%

|V|Vubub| from B | from B ππℓℓνν

For |Vub|: Lattice QCD: q2>16 GeV2

Light-cone sum rules: q2<16 GeV2

FF normalization errors dominate; task for theory, CLEO-c

|Vu

b|

from

excl

usi

ve d

eca

ys

New

New

New

New

New

New

New

New

New

6% uncertainty

Averages of tagged and untagged methods are comparable

FF calc Vub [10-3] FF norm (ps-1) Ref

Ball-Zwicky 5.44 ± 1.43 PRD 71:014015 (2005)

HPQCD 1.46 ± 0.35 PRD 73:074502 (2006)

FNAL 1.83 ± 0.50 hep-lat/0409116

APE 1.80 ± 0.86 Nucl. Phys. B619:565 (2000)

1.360.63 -

0.610.40 -

0.590.41 -

0.560.37 -

0.23 3.54

0.23 3.51

0.26 3.93

0.12 3.38

Page 25: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 25

The phase: γ (φ3)

tbtsi

td

cbcscd

iubusud

VVeV

VVV

eVVV

See talks of Marchiori, Krokovny, S8

Page 26: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 26

The relative phase The relative phase γγ ( (φφ33))Interference between tree-level decays; theoretically clean

Parameters: γ, (rB, δB) per mode

Three methods for exploiting interference (choice of D0 decay modes):

• Gronau, London, Wyler (GLW): Use CP eigenstates of D(*)0 decay, e.g. D0 Ksπ0, D0 π+ π -

• Atwood, Dunietz, Soni (ADS): Use doubly Cabibbo-suppressed decays, e.g. D0 K+π -

• Giri, Grossman, Soffer, Zupan (GGSZ) / Belle: Use Dalitz plot analysis of 3-body D0 decays, e.g. Ks π+ π-

Vcs* Vub: suppressedFavored: Vcb Vus

*

b

u

s

u u

b

u

cD(*)0

K(*)-

B- B-

u

s

u

c

D(*)0f

Common

final state

K(*)-

iiBKDBA

KDBA eer B

0

0

Page 27: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 27

GLW-based analysesGLW-based analyses Measure asymmetry between B+/B- for CP even/odd D decays

and the fractional decay rates to CP eigenstates:

coscos21

sinsin22

BBB

BBCP rr

r

KDBKDB

KDBKDB

coscos21 2

00 BBBCP rrKDBKDB

KDBKDB

Belle 275 106 BB

B+DCP+K+

B+DCP+π+

Signals seen in CP-even and CP-odd D decays

The a

ng

le γ

3)

Hard to disentangle rB from γ and δB

8-fold ambiguity on γ

Similar measurements exist in B+ D*0 K+

CP-even D0 modes

CP-odd D0

modes

B+DCP-

K+

BaBar 232 106 BB

B+DCP-π+

Recent results: Belle (PRD 73:051106, 2006), BaBar (PRD 73: 051105, 2006)

Page 28: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 28

GLW averagesGLW averages

DC

P K

*D

* CP K

DC

P K

The a

ng

le γ

3)

Implications for rB and γ discussed later

Page 29: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 29

ADS-based analysesADS-based analyses

Use DCS decays to reach same final state, e.g.The a

ng

le γ

3)

π)(KK

π)(KK00

00

nDDB

nDDB

favored suppressed

suppressed favored

Small product BF but comparable amplitudes large potential asymmetry

coscos2

sinsin2

22DBDBDBADS

ADS

DBDBADS

rrrrKKBKKB

KKBKKB

rr

KKBKKB

KKBKKB

DB iδD

iγiδBKπKDBA

KπKDBA ereer

Additional parameters rD and

δD

DCSD charm;rD (Kπ)= 0.0603 ±

0.0025

Direct dependenceModes D*K and DK* also used

D*0 D0π and D*0 D0γ have opposite CP

Page 30: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 30

Belle hep-ex/0508048 386 106 BB

[K+π-]D K- [K-π+]D K-

ΔE

ADS resultsADS resultsThe a

ng

le γ

3)

c.l.) (95% 390.0 DK

New BaBar result in [K+π-

π0]DK-

BaBar preliminaryhep-ex/0607065 226 106 BB

mES

Belle result in [K+π-]DK-

No signal yet in suppressed

modes

c.l.) (90% 140.0 DK Implications for rB and γ discussed later

Page 31: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 31

Dalitz analysesDalitz analyses Measure B+/B- asymmetry across Dalitz plot

Includes GLW (D0 Ks ρ0, CP eigenstate) and ADS (D0 K*+π-, DCS 2-body decay) regions

The a

ng

le γ

3)

2222 ,,

mmfeermmfA BiiB

KKB Ds

Sensitivity to γ in interference term

2-fold ambiguity on γ: (γ, δ)→ (γ+π,

δ+π)

decay amplitude

Determine f in flavor-tagged D*+D0π+ decays

sKmm 22Mirror symmetry

between D0 and D0 Dalitz plots

Page 32: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 32

Dalitz model for KDalitz model for Kssππ++ππ--

Select D*+[Ksπ+π-]π+ from e+e- cc; ~4 105 events

Fit to coherent sum of 15-16 Breit-Wigneramplitudes plus a non-resonant term

The a

ng

le γ

3)

m2+

(GeV2)

m2- (

GeV

2)

Belle 357 fb-1

preliminaryhep-ex/0604054

BaBar 270 fb-1

preliminary

m2(π+π-) GeV2

Excellent fits obtained

Main contributors:

• K*-(892) π+

• Ks ρ0

• K*0(1430) π -

• K*-(892) π+

• non/broad resonant

Model-independent approach (GGSZ) using CP-tagged D0 studied by Bondar, Poluektov in hep-ph/0510246

Improved modeling (e.g. K-matrix formulation) under study

Page 33: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 33

Plots shown are representative; both experiments have analyzed DK, D*K and DK* decays

Dalitz plotsDalitz plotsThe a

ng

le γ

3)

Belle hep-ex/0604054

D*K-

386 106 BB

D*K+

347 106 BB

BaBar preliminary

DK-DK+

Page 34: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 34

Results on Results on γγ

HFAG averages for x± = rB cos( δB ± γ ) , y± = rB sin( δB ± γ ) UTfit find γ = 78±30° based on B- D(*) K(*)- decays Note: σγ depends significantly on the value of rB

The a

ng

le γ

3)

Contours do not include Dalitz model errors

Contours do not include Dalitz model errors

rB

Page 35: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 35

sin(2sin(2ββ++γγ))The a

ng

le γ

3)

Parameters: γ, 2β

(r, δB) per mode

Vcd* Vub: really suppressedreally favored: Vcb Vud

*

b

d

d

u b

d

d

cD(*)+

π-

B0 B0

c

d

d

u

D(*)-

2 common final states

via BB mixing

π+

2

favored

suppressed iiB eer

A

AB

Large BF but small rB (<2%) small CP

asymmetry

rB must be estimated from

B0Ds+π – using SU(3)

Time-dependent effect

(due to B0-B0 mixing)

Page 36: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 36

BB00 D D00 K K00 feasibility study feasibility studyThe a

ng

le γ

3)

BaBar hep-ex/0604016, soon in PRD

• Interference of B0 D0 K0 withB0 B0 D0 K0 (K0 and K0 mix)

• Determine rDK* in related decay B0 D0 K*0

• BaBar find no signal: rDK* < 0.4 @90% c.l.

• This mode may be harder to use for sin(2β+γ) than predicted; implications for LHC-b

B0D0

K*0

Vu

b

B0 D0 K*0

ΔE

B0D0

K*0

Vcb

Page 37: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 37

Related measurementsRelated measurements

BaBar PRD D73 \:071103 (2006)

c.l. 90% ,10

20

19

6.3

9.1

5

2*

2

0*

0

aDBBF

aDBBF

aDBBF

aDBBF

s

s

s

s

B0 Ds a0,2

Nice ideas, nice work, but not much impact

yet for γ

226 106 BB

rDπ from B0Ds(*)π -,

SU(3)

2

5

*

*

102.02.09.1

1.02.03.1

10

4.05.00.2

4.04.05.2

5.06.08.2

2.03.03.1

*

D

D

s

s

s

s

r

r

KDBBF

KDBBF

DBBF

DBBF

BaBar hep-ex/0604012, 226 106 BB

preliminary

BD*D*

The a

ng

le γ

3)

BF and charge asymmetries measured for all B D(*)D(*)

modes; provides input for sin(2β+γ) from B0 D(*)+D(*)- time-dependent asymmetries

BaBar PRD 73:112004 (2006)

BaBar show that B D0

K+π- not promising for measuring γ

BaBar PRL 96:011803 (2006)

B0 D0 K+ π -

Page 38: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 38

Current status of UTCurrent status of UT

Tree-level determination: information on phase γ (φ3) not yet constraining

All constraints: compatible with SM, but tension exists between sin2β and |Vub/Vcb|

The a

ng

le γ

3)

“2-σ” bands

See talks of Vagnoni, T’Jampens, S8

Page 39: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 39

SummarySummary Today:

What to look for in 2008: 2 ab-1 from the B factories

(>doubling of data sample) error on |Vub/Vcb| of ~5%

error on γ: ~10-15° ? (rB …) LHC-b will have initial data

The heavy flavor program will restrict the space in which theories for the new physics to be seen at LHC can operate

3078)(φγ

1027.019.0494.V

1069.023.00.24V

3

3ub

3cb

“2-σ” bands

Page 40: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 40

Backup slides

Page 41: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 41

Tale of two fittersTale of two fitters

CKMfitter (frequentist)

UTFit (Bayesian)

Page 42: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 42

Theory calculationsTheory calculations

Bosch, Lange, Neubert, Paz (BLNP) Decompose into Hard, Jet and Shape functions using HQE

and SCET: H×J ×S Same formalism used to extract mb and μπ

2 from bsγ Predictions over full phase space, reasonable error analysis Critique: 3 scales between ΛQCD and mb

Andersen and Gardi: Dressed gluon exponentiation (DGE) Only mb and αS as input parameters Gives good description of bsγ spectrum Agrees fairly well with BLNP on buℓν rates Critique: some (but not all) consider it a model;

|Vu

b|

from

in

clusi

ve

deca

ys

Page 43: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 43

Global fit: Input Global fit: Input measurementsmeasurements

Moments used in fit, from B Xcℓν and b sγBuchmüller and Flächer,Phys.Rev. D73 (2006) 073008

\ MomentExperiment

Electron energy

Hadronic mass Photon energy

Delphi 3 3

CLEO need full covar 4 1

CDF 2

Belle need full covar need full covar 4

BaBar 14 13 3

|Vcb

| fr

om

in

clusi

ve

deca

ys

Page 44: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 44

BBXXccℓℓνν using using

tagged samplestagged samples Reconstruct D(*)Xℓ-ν across from a fully reconstructed

B+ or B0 meson; Mmiss2 provides new kinematic handle

Belle reported last year BFs for B D(*)πℓν: Phys.Rev.D72:051109,2005 Also report BF(B-D*0ℓ-ν) = 6.06 ± 0.25stat%;and BF(B0D*+ℓ-ν) = 4.70 ± 0.24stat%.

New BaBar preliminary result:BF(B-D*0ℓ-ν) = 6.8 ± 0.4%BF(B-D0ℓ-ν) = 2.3 ± 0.3%BF(B-D**0ℓ-ν) = 1.9 ± 0.3%(includes D(*)πℓν; translated from relativefractions into BFs by this speaker assumingthese modes saturate bcℓν)

New D0 result (preliminary)BF(BsDs1(2536)ℓν) = 0.86 ± 0.16 ± 0.16

BelleBF (in %)|V

cb|

from

excl

usi

ve d

eca

ys

D

D*

D(*)π

Page 45: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 45

The BF(BThe BF(BDD**ℓℓνν) puzzle) puzzle The largest B BF is BD*ℓν (~6%), yet B K*γ (~4×10-5) is

known as well, and perhaps better…

(HFAG winter) average: BF(B0D*+ℓ-ν) = 5.35 ± 0.20%; CL=3.8%

Consider RD* = BF(B-D*0ℓ-ν) / BF(B0D*+ℓ-ν); we expect RD* = τ+ / τ0 = 1.071 ± 0.009

Naively combining Belle and BaBar results: RD*

= 1.32 ± 0.07(20% and 3.5σ from isospin!)

|Vcb

| fr

om

excl

usi

ve d

eca

ys

BaBar preliminary

Ee

BF(B+Xeν) / BF(B0Xeν)= 1.084 ± 0.041 ± 0.025

Total BF(BXℓν) consistent with isospin

Page 46: Measuring the apex: |V ub |, |V cb | and their  relative phase  γ  ( φ 3 )

ICHEP '06 Kowalewski 46

Importance of rImportance of rBB

The uncertainty on γ (φ3) depends strongly on the value of rB, which is currently not well known

Predictions for how σγ will evolve with luminosity have significant uncertainty

rB

φe

Belle