rare b decays at mousumi datta university of wisconsin, madison on behalf of the babar collaboration...

Rare B Decays at

Mousumi DattaUniversity of Wisconsin, Madison

On behalf of the BaBar Collaboration

XII International Workshop on Deep Inelastic Scattering 14-18 April 2004

22

OutlineOutline Introduction

Motivation Experimental techniques

Rare hadronic B decays Radiative and electroweak B decays Purely leptonic B decays Summary Summary

All results are preliminary unless referenced.

DIS 2004Mousumi Datta, University of Wisconsin-Madison

33DIS 2004Mousumi Datta, University of Wisconsin-Madison

SM and Rare B DecaysSM and Rare B Decays Good agreement between Standard Model (SM) and the experimental results up to now.. To be sensitive to possible new physics (NP) and to test SM consider decays with small SM rates. Look at : Look at :

Processes dominated by penguin loops CKM suppressed decays Purely leptonic decaysR

are

B

Deca

ys

44

SM and Rare B Decays (cont’)SM and Rare B Decays (cont’)

New physics particles in loops

might show up in:

Different rates, kinematic distributuios than SM only

Different CP violation than SM only


Constrain the SM Time dependent CP measurements (L. Li Gioi’s talk) Direct (time integrated) CP measurement Decay rates

Compare theoretical predictions Constrain CKM parameters : |Vtd/Vts| from BK*,

Kinematic distributions : K*, Xsl+l-

55

Direct CP AsymmetryDirect CP Asymmetry Different decay rates for B Different decay rates for B f and B f and B f f

needneed 2 decay amplitudes2 decay amplitudes withwith different weak phase different weak phase and and different strong phasedifferent strong phase: :

( ) ( )

( ) ( )CP

N B f N B fA

N B f N B f

)cos()cos(2

)sin()sin(2

12122122

21

12122122

22

)(2

)(1

)(2

)(1

22112211

aaaa

aa

aa

aaA

eaeaaeaeaa

ff

ff

CP

iif

iif

Weak phase difference

Strong phase difference

Penguin-dominated decays like B K(*), K, K* have small ACP in SM sensitive to extra CP-violating phases due to NPDIS 2004

Mousumi Datta, University of Wisconsin-Madison

66

PEP-II Luminosity PerformanceBest Peformance

PEPII peak Luminosity : 8.305x1033 cm-2 sec-1

24 hours : 660.5 pb-1 On-peak (fb-1)

Run 1+2 82

Run 1+2+3 113

Run 4 data taking in progress:

~100 fb-1 by July 2004.


89.7106 BB82 fb-1

on-peak data for analysis

124.1106 BB

77

Standard Variables in Standard Variables in (4S) Frame(4S) Framee+e- (4S) BB B produced almost at rest in (4S) frame

For B decay with no missing particles use beam energy to constrain mass and energy of the reconstructed B

**beamB EEE

background

signal

background

0 for signal0 for signal mB for signal**beamB EEE 22

BbeamES PEm

E and mES provide uncorrelated measurement of energy and massDIS 2004Mousumi Datta, University of Wisconsin-Madison

88

Rare Hadronic B DecaysRare Hadronic B Decays Suppressed at tree(T) level due to Cabbibo, FCNC, etc. Significant Penguin (P) contribution.

Hadronic decay modes covered in the talk

Tree diagram Penguin diagram


B , K, KKB → ρρ and ρK*B K(*)/B (')K(*) and (')/B () ()

99

BB • Measure Measure effeff from time dependent CP analysis from time dependent CP analysis

of Bof B00++- - decaydecay

• Constrain using isospin connection for decays

BF(B0+-)=

(4.70.60.2)10-6

(PRL, hep-ex/0207055)

B0+-

@ 82 fb-1

60.19.0

0

10)6.05.5(

)(BF

B

(PRL, hep-ex/0303028)(PRL, hep-ex/0303028)


d

u

u

Tree CKM suppressed

Penguin diagram

B+-

Color suppressed

tree for B00

B++0 @ 82 fb-1

1010

B000 @ 113 fb-1

BF(B000) = (2.1 ± 0.6 ± 0.3)10-6

Observed events = 46 ± 13 ± 3(PRL ,hep-ex/0308012)(PRL ,hep-ex/0308012)

SM prediction BF ~ (0.3-1.1)10-6

4.2

0

0002

(

(sin

BBF

BBF

With WA Br(B00 )

|-eff |<48o at 90% c.l.

BB (Cont’) (Cont’)

Observation of significant excess of 00 events

Bound on penguin pollutionGrossman Quinn bound PRD 58

(1998) 017504

1111

Summary of BF (10-6) for K, and KKModeMode BF (10BF (10-6-6)) AAcp cp L (fbL (fb-1-1))

K+ - 17.9 0.9 0.7

-0.1070.0410.01

3

82, 113

K0 + 22.31.71.1 -0.050.080.01 82

K+ 0 -0.090.090.01 82

K0 0 11.4 1.7 0.8

0.030.360.11 82

+ - 4.7 0.6 0.2

- 82

+ 0 82

0 0 2.1 0.6 0.3

- 113

K+ K- < 0.6 @ 90% CL - 82

K+ K0 < 2.5 @ 90% CL - 82

K0 K0 < 1.8 @ 90% CL - 82

6.05.5 0.19.0

0.18.12 2.11.1

02.003.0 18.017.0

KK decays more sensitive to rescattering : No sign of rescattering (FSI) yet

Acpconsistant with zero

Ratio of BF for and K sensitive to angle


Time dep. CP analysis of Ks0 using 113 fb-1

Measure sin2

PRL

1212

((++--)/)/(K(K++--)) 0.26 0.26 ± ± 0.04 0.04 ± ± 0.020.02

(K(K++--)/)/(K(K00++)) 0.87 0.87 ± ± 0.08 0.08 ± ± 0.050.05

22(K(K++00)/)/(K(K00++)) 1.15 1.15 ± ± 0.14 0.14 ± ± 0.120.12

(K(K++--)/2)/2(K(K0000)) 0.79 0.79 ± ± 0.12 0.12 ± ± 0.060.06

Isospin ratios

<< 1/2

if tree only

Significant Penguin contribution Isospin symmetry holds well for penguin dominated modes( EW penguin small) Need more statistics for further constraint

Isospin sum rule (Gronau et. al. (2003), hep-ph/0307095) (Lipkin)

BaBar: 1.21 0.13 Belle(LP03): 1.25 0.15 New Physics ?

22

2

00

0000

||

)*Re(

||

||1

)()(

)()(2

P

PT

P

P

KBKB

KBKB EWEW

K and

< 4%

*Ratios calculated by speaker, assuming errors are uncorrelated


1313

B → ρρ, ρK* and K(*)/

2

2 2 2 21 2 1 2

1 2

1 11 sin sin cos cos

cos cos 4 L L

df f

d d

BVV: Longitudinal polarization

( fL ≡ L / )

Expect:

fL ~ 1 – O(M2V/M2

B)

Time dependent CP analysis: Sin(2) K0 and Sin(2eff) from

Search for direct CP violation.


1414

B0 + -

NS = 224 ± 29

B B → → ρρρρ and and ρρKK**

ModeMode BF (10BF (10-6-6)) Polarization Polarization ((LL//))

AACPCP

BB00++-- 30 30 4 4 5 5 --

BB++→→ρρ++ρρ00 --0.190.190.230.230.00.0

33

BB00→→ρρ00ρρ00 <2.1 <2.1 @90%CL@90%CL -- --

BB++→→ρρ00K*K*++ )(.

)(.)(sin

0

0002

0

00

BBFf

BBFf

L

LEff

| - Eff| < 13o () at 68% CL

Grossman Quinn bound PRD 58 (1998) 017504

04.003.003.099.0

8.55.22 7.5

4.5

4.26.10 0.36.2

04.097.0 03.007.0

04.096.0 04.015.0

04.020.0 32.029.0

100% Longitudinal Polarization CP even


L=82 fb-1PRL

Time dep. CP measurement for +- also updated with 113 fb-1. (preliminary)

1515

B B K K(*)(*)//

Mode BF (10-6) ACP Polarisation

K0 - -

K+ 0.040.090.01

-

+ <0.41 @ 90% CL

- -

K*0 11.21.30.8 0.040.120.02

0.650.070.02

K*+ 0.160.170.03

0.460.120.03

Expect similar BF all KK(*)(*) modes BF(+)<410-7 [90% CL](No indication for rescattering – as KK) Polarisation small

5.06.7 3.12.1

5.00.10 9.08.0

1.17.12 2.20.2

hep-ex/0309025

hep-ex/0307026 L=82 fb-1


Small fL still not understood – may be related to penguins

[Bauer, Pirjol, Rothstein, Stewart, hep-ph/0401188; Kagan]

BK*0 full angular analysis

with 113 fb-1

fL = 0.52 0.07 0.02

(preliminary)

1616

(')K(*) and (')(')//

Decays () and + are dominated by tree diagram as penguin diagrams are suppressed.

K, K*enhanced

K, K*suppressed

Interference

Flavour singlet diagram:

Also important for K*

CKM suppressed

H Lipkin Phys Lett B254 (1991) 247

Similarly for K0, K*0 except no external tree.


1717

((,,)()(K,K,,,K*,K*,,,00), ), 00, , 00

PR

L 9

1, 1

6180

1 20

03,

PR

L 9

2,0

61801 2

004

Su

bm

itte

d t

o P

RD

h

ep

-ex/0

403025

L=82 fb-1

K BF 3-10 times larger than initially expected values. In agreement with recent NLO QCD prediction (Beneke and Neubert, (2003) Nucl. Phys. B 651, 225).

Large asymmetry predicted for +, small for +

Chiang, Gronau, Luo, Rosner and Suprun [hep-ph/0307395]


K* measurement not precise enough to determine the presence of flavor singlet component.

1818

CLEO

Isoscalar (Isoscalar (,,,,,,)()(,,,,,,)) 8 of 10 combinations , , , , , , ,

(not , )

L=82 fb-1Submitted to PRL


1919

Correlated bounds on CP asymmetries in B0Ks

Gronau, Rosner &

Zupan, hep-ph/0403287, April 2004]

Predictions for Predictions for KKss Time Dependent Time Dependent

asymmetry asymmetry S,CS,C

HFAG average


From 00, 0, 0’, , ’’, ’

From 00, K+K-, 0, ’

Previous bounds

Similar bounds from [Grossman-Ligeti-Nir-Quinn, PRD 68, 015004 (2003).]

2020

Rare decays aren’t so “rare”Rare decays aren’t so “rare”


2121

BBK*K* and and //BB// :: (PRL, (PRL,

hep-ex/0306038)hep-ex/0306038)BBK*K*

(Preliminary)(Preliminary)

Iso-spin asym. 0-=

= 0.0510.044(stat) 0.023(sys) 0.024(R+/0)

SM prediction: (+5 to +10)%

)()(

)()(*0*0

*0*0

KBKB

KBKB

Time dep. CP analysis

B0 K*0(Ks0) with 113

fb-1

Prediction MeasurementBF(B0K*0(K+-,K0

s0)) 7.5 3.0 3.920.200.24 BF(B+K*+(K+0,K0

s+)) 7.5 3.0 3.870.280.26 ACP(K*(K+-, K+0, K0

s+) < 1% -0.0130.0360.010 BF(B00(+-)) 0.5 – 0.75 < 1.2BF(B++(+0)) 0.8 – 1.5 < 2.1BF(B0(+- 0)) 0.5 – 0.75 < 1.0

10-5

10-6@ 90% CL

L=

82

fb-1

L=

78 f

b-1


2222

L=82 fb-1Semi-inclusive BSemi-inclusive BXXss

Acp = 0.0250.050.015 (for total sample)

Acp = -0.040.100.02 (for high purity sample)

Submitted to PRL

Xs fully reconstructed

in 12 exclusive

self-tagging modes


2323

BBKK(*)(*) ll++ll--

SM Prediction (10-6)BF(B → Kl+l-) = 0.350.12 BF(B → K*e+e-) = 1.580.49BF(B K*+-) = 1.190.39

Ali et al. (hep-ph/0112300, 2001)BK*l+l-

BKl+l-

614.013.0 1004.065.0

lKlBBF

633.029.0

* 1010.088.0

llKBBF

L=113.1 fb-1

3.3

>8

PRL, hep-ex/0308042PRL, hep-ex/0308042

,,

,,

,

,,

0

0*0*

0*0*

00

elK

KKKK

llKBllKB

llKBllKB

s

s

s


2424

L=82 fb-1

Semi-inclusive BSemi-inclusive BXXssll++ll- -

Less theoretical uncertainty Observables: BF, m(l+l-), m(Xs), AFB(m(l+l-))

68.15.1 10))()(6.13.6(

)(

syststat

llXBBF s

• Xs reconstructed in 10 modes: uncounted states ~25% of the total rate

• In signal region m(l+l-)> 0.2 GeV/c2 4110(stat)2(syst) events observed

Prediction for m(l+l-)>0.2 GeV/c2: (4.20.7)10-6 (Ali, hep-ph/0210183, 2002)


Xse+e- Xs+-

Xsl+l- Xse

2525

BBKK FCNC transition 2 ’s in the final state Reconstruct one B & look for signal in the recoil side

B- K-simulation

Data

80.7 fb-1 BF < 1.05 x10-4

@ 90% CL

Hadronic B SampleHadronic B Sample Semileptonic B SampleSemileptonic B Sample

Combined limit @ 90% CL < 7.0 x 10Combined limit @ 90% CL < 7.0 x 10-5-5

50.7 fb-1

BF < 9.4 x10-5 @ 90% CL

SM Expectation: ~ 410-6


2626

B++ at

81.4 fb-1

B++ simulation

DataData

BF(B++) < 6.610-6 @ 90% CL

(PRL)

• Purely leptonic decay are Purely leptonic decay are helicity suppressed in SMhelicity suppressed in SM

• B+l+ : SM expectation:

BF(B++) ~ 410-7

BF(B++) ~ 910-5

• Provide measurement of fB|Vub|

• Sensitive to charged Higgs, leptoquarks.

BB++ll++

L=81.4 fb-1


2727

BB• Multiple ’s in the final state Reconstruct one B & look for signal in the recoil side.

Combined limit

BF < 4.1 x 10-4 at 90% CL

Semileptonic B SampleIncludes e,

total ~ 0.07 %BF < 4.9 x10-4 @ 90% CL

L=81.9 fb-1

Hadronic B Sample Includes e, , , 0, 3

total ~ 0.028 %BF < 7.7 x10-4 @ 90% CL

Existing tightest limit (L3) Existing tightest limit (L3)

BF < 5.7 x 10BF < 5.7 x 10-4-4 at 90% CL at 90% CL

Eextra (GeV)

Semileptonic SampleSemileptonic Sample


2828

SummarySummary Large amount B mesons produced at B-factories

First observation of many rare decay modes More precise measurement of BFs Tighter upper limits on BFs

BaBar haven’t seen evidence of direct CP violation yet. Precise measurements of ACP in future will enable further tests of models.

No strong evidence of NP. Measurements and search for many more rare

decay modes continuing The expected increase in luminosity of the B

Factories promises a continuing, rich harvest of physics


Stay tuned for the summer results.

2929

Backup Slides Backup Slides

3030

PEP-II Asymmetric B-Factory at SLACPEP-II Asymmetric B-Factory at SLAC

Asymmetric collider operation at (4S) resonance (Ecms=10.58 GeV)

3.1 GeV e+ and 9 GeV e-

B-mesons in lab have =0.56

(4 )e e S BB

B B production threshold


3131

The BaBar DetectorThe BaBar Detector

DIRC PID)144 quartz bars

11000 PMs

1.5 T solenoid EMC

6580 CsI(Tl) crystals

Drift Chamber40 stereo layers

Instrumented Flux Return

iron / RPCs (muon / neutral hadrons)

Silicon Vertex Tracker5 layers, double sided

strips

e+ (3.1 GeV)e- (9 GeV)

SVT: 97% efficiency, 15 mm z hit resolution (inner layers, perp. tracks)SVT+DCH: (pT)/pT = 0.13 % pT + 0.45 % DIRC: K- separation 4.2 @ 3.0 GeV/c 2.5 @ 4.0 GeV/c EMC: E/E = 2.3 %E-1/4 1.9 %DIS 2004

Mousumi Datta, University of Wisconsin-Madison

3232

Continuum SuppressionContinuum Suppression

B Signal

u,d,s,cbackground

Fisher Discriminant

Arb

itrar

y U

nits

e+ e-e+ e-

qq

Signal B

Other B

B decays: isotropic

Examples of topological variables using these properties: Thrust

Energy cones

Continuum (u,d,s,c): jet-like

2

,20 cos, iTROEi

iROEi

i BpLpL

Variables are used in a Fisher or a Neural Net (NN)DIS 2004Mousumi Datta, University of Wisconsin-Madison

3333

BF & ABF & ACPCP for B for B , , K, K, , , KK

Mode BF (10-6) ACP L (fb-1)

BB00 → → ρρ ππ 22.61.82.2 -0.110.060.0

3

82 (PRL), 113

BB00 → → ρρ- - KK++ 0.180.120.08

82 (PRL)

BB00 → → ρρ0 0 ππ00 < 2.9 @ 90% CL - 82 (PRL)

BB++ → → ρρ+ + ππ00 10.91.91.9 0.240.160.06

82 (PRL)

BB++ → → ρρ0 0 ππ++ 9.51.10.9 -0.190.110.0

2

82 (PRL)

BB++ → → ρρ00 K K++ <6.2 @ 90% CL - 56.4 (PRL)

BB00 → → ωω KK00 - 82 (PRL)

BB++ → → ωω KK++ 4.8 0.8 0.4 -0.090.170.0

1

82 (PRL)

BB00 → → ωω ππ00 < 1.2 @ 90% CL - 82 (PRD)

BB++ → → ωω ππ++ 5.50.90.5 0.030.160.01

82 (PRL)

3.13.7 3.12.1

5.09.5 6.13.1

Measure eff from time dependent

CP analysis of

BF of and K are in good agreement with theoretical expectation.


3434

BB K*K*00 full angular analysisfull angular analysis

Direct rate asymmetries Triple-product asymmetries

Fit results


L=113 fb-1Preliminar

y

3535

BB K*K*00

No evidencefor Direct CP violation

B

f L=

0.52

0.07

0.0

2

Weak evidence for FSI (2.3

Triple-productasym. (1.7(would beevidence forNew PhysicsDatta&London hep-ph/0303159)


3636

BABAR94±14(stat)±6(syst) evtsL=111fb-1

TotalContinuumAll bgk.

BABAR TotalContinuum

All bgk.

B0f0(980)Ks , f0+-First Observation

• Structure of this scalar meson obscure. Recent studies favor usual qq states [hep-ph/0011191(2000)]

648

2/)(sincos0

s

ss dduussf

Decay can be dominated by bsss penguin

• ss sizeable• buus tree doubly Cabbibo suppressed compared to leading penguin

• Time dependent CP measurement(see L. Ligioi’s talk)

BF(B0f0(980)(+-)K0) =

(6.0 0.9 0.4 1.2)10-6


L=111 fb-1

Preliminar

y

3737

BB a a00(980)((980)(K,K,,,KKSS))Dominant tree diagram G-parity suppressed

Dominant penguin

a0K

a0

aa00++

negligible compared with anegligible compared with a00-- (G-parity) (G-parity) “self-tagging” “self-tagging”

aa00KK expected to be small (Wilson-coefficient cancellation) expected to be small (Wilson-coefficient cancellation)

Chernyak, PLB 509, 273 (2001).Chernyak, PLB 509, 273 (2001).

3838

BB a a00(980)((980)(K,K,,,KKSS) ) PRELIMINARY

Unbinned ML fits (89M BB events); aUnbinned ML fits (89M BB events); a0 0 , , ,3,3 Only previous search from BABAR (20 fbOnly previous search from BABAR (20 fb-1-1, LepPho 2001), LepPho 2001)

Found 3.7Found 3.7 evidence for evidence for BB 00 a a00(980)(980)--++

Do not confirm that with substantially improved sensitivityDo not confirm that with substantially improved sensitivity• Studies indicate the previous result was a statistical fluctuationStudies indicate the previous result was a statistical fluctuation

B is B(B a0X)B(a0

L=82 fb-1

3939

BB KKS S branching fractionbranching fraction

B(BB(B KK00 ++--) = (43.8 ) = (43.8 ± ± 3.8 3.8 ±± 3.4) 3.4)1010-6-6

Comparable to, but more precise than, previous resultsComparable to, but more precise than, previous results• CLEO (50CLEO (50 ± ± 10 10 ±± 7) 7)1010-6-6

• Belle (45.4 Belle (45.4 ± ± 5.2 5.2 ±± 5.9) 5.9)1010-6-6

Measurement of the branching Measurement of the branching fraction integrated over the fraction integrated over the Dalitz plotDalitz plot

Careful corrections for Careful corrections for efficiency across Dalitz plotefficiency across Dalitz plot

Consistency check fromConsistency check from

BB00 D D--++ with D with D-- KKSS--

L=82 fb-1

4040

BB00→K→K++KK--KKSS and B and B++→K→K++KKSSKKSS

3 body decay 3 body decay BB00→K→K++KK--KKSS (excluding (excluding BB00→→KK00))

Time dependent CP analysis: Sin(2) Determine Determine CP-CP-even fraction using even fraction using

Branching fraction measurements Branching fraction measurements Isospin symmetry Isospin symmetry [Belle Collaboration, [Belle Collaboration,

Phys. Rev DPhys. Rev D6969, 012001 (2004)]:, 012001 (2004)]:

)(

)(200

00

KKKB

KKKBf SS

even

B0→K+K-KS

201±16 events

L=111 fb-1

B+→K+KSKS

122±14 events

BABAR


BF(BF(BB00→K→K++KK--KK00)= )= (23.8(23.8±2.0±1.6±2.0±1.6))×10×10-6-6

BF(BF(BB++→K→K++KKSSKKSS)=(10.7)=(10.7±1.2±1.0±1.2±1.0))××1010-6-6

ƒƒeveneven=0.98=0.98±0.15±0.04±0.15±0.04

Acp(BAcp(B++KK++KKssKKss) = -0.042 ) = -0.042

0.114(stat) 0.114(stat) 0.02(syst) 0.02(syst)

L=113 fb-1

4141

B+→K+K-K+

B+→K+ -+

B+ + - +

BF (10BF (10-6-6)) AACPCP

++ -- ++ 10.9 10.9 3.3 3.3 1.6 1.6 -0.39 -0.39 0.330.33 0.12 0.12

KK++ -- ++ 59.1 59.1 3.8 3.8 3.2 3.2 0.01 0.01 0.07 0.07 0.03 0.03

KK++ K K-- K K++ 29.6 29.6 2.1 2.1 1.6 1.6 0.02 0.02 0.07 0.07 0.03 0.03

KK++ K K-- ++ < 6.3 @ 90% CL< 6.3 @ 90% CL N/AN/A

++ K K-- ++ < 1.8 @ 90% CL< 1.8 @ 90% CL N/AN/A

KK++ -- K K++ < 1.3 @ 90% CL< 1.3 @ 90% CL N/AN/A

Charmless BCharmless B++hh++hh--hh+ + (h=K, (h=K,))• Search for direct CPV. Measure through the interference between various

charmless decays and c0 resonance (Blanco

et al, Phys.Rev.Lett.86,2720(2001))

• Measurement of B+++- can be used to reduce uncertainty in

measurement (Snyder and Quinn, Phys. Rev. D48,

2139(1993))

L=81.8 fb-1

PRL (hep-ex/0304006)PRL (hep-ex/0304006)


4242

Exclusive Branching Fractions of BExclusive Branching Fractions of B++KK++- - + +

BF (10BF (10-6-6))

BB++ KK*0*0(892)(892)++, K, K*0*0 KK++ --

BB++ ff00(980)K(980)K++, f, f0 0 ++--

BB++ c0c0 K K++, , c0c0 ++-- 1.51.50.40.40.10.1

BB++ DD00++, D, D00 KK++ -- 184.6184.63.23.29.79.7

BB++ higher Khigher K*0*0++, K, K*0*0 KK++ --

BB++ 00(770)K(770)K++, , 00 ++-- <6.2 at 90% CL<6.2 at 90% CL

BB++ KK++ - - ++ (non resonant) (non resonant) <17 at 90% CL<17 at 90% CL

BB++ AAhigher fhigher f@@ K K++, f , f ++-- <12 at 90% CL<12 at 90% CL

5.10.48.15.15

L=56.4 fb-1j

c0

f0(980)

0

higher K*0

D0

K*0(892)

(veto)J/

(2S)

1.26.22.12.9

9.49.20.21.25 4.95.0

Search for direct CPV Measure through the interference between various charmless decays and c0 resonance

Submitted to Phys.Rev.Lett. (hep-ex/0308065)Submitted to Phys.Rev.Lett. (hep-ex/0308065)

Dalitz plot divided into 8 regions

• K*0(892)+ BF result significantly higher than prediction from many factorization models.• Limit on non-resonant component dependent interference will be hard to measure


4343

Inclusive bInclusive bss L=54.6 fb-1

Signalregion

Onpeakdata

Backgroundexpectation

Signal Region2.1 < E*

< 2.7 GeV

443.0

23.0 10)](mod.)(37.0)(36.088.3[

elsyststat

XBBF s


4444

BB00ll++ll--

FCNC processFCNC process

B0l+l- : SM Expectation:

BF(B0e+e- ) : 1.910-15 BF(B0+-) : 8.010-11

In various SUSY models BF enhanced, B0e allowed.BB00ee++ee-- BB00++-- BB00ee

BF(BBF(B00ee)<2.1)<2.11010-7-7BF(BBF(B00ee++ee--) < 3.3) < 3.31010-7-7

Upper limits at 90% CL:

BF(BBF(B00++--)< 2.0)< 2.01010-7-7

L=54.4 fb-1


4545

Fully reconstructed B Meson in Hadronic decays: D(*)(n) Semileptonic decays:

D(*)l (statistically independent)

Look for process of interest in the Recoil

Pro: Background suppression!

Con: Statistics limited

‘other’ B

Brecoil

BrecoD* Y(4S) l

For search of rare decays like BK, B ....

RecoilRecoil Analysis Analysis

sidebandsideband peakpeak

Hadronic BHadronic B Sample Sample

N N BBBB = (1.67 = (1.670.09)0.09)10105 5 @ 81.9 fb@ 81.9 fb--

11DIS 2004Mousumi Datta, University of Wisconsin-Madison

rare b decays at mousumi datta university of wisconsin, madison on behalf of the babar collaboration...

Documents

b b measure

madisonrare hadronic

rare b decaysdis

s bb b

s framefor b decay

reconstructed b background0

sm sensitive

leptonic decaysrare