Luca Lista

L.Lista INFN Sezione di Napoli

Rare and Hadronic B decaysRare and Hadronic B decays in B in BAABBARAR

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OutlineOutline

• Charmonium decays Inclusive Exclusive J/ K* angular analysis

• Open Charm• 2-body hadronic decays• quasi 2-body decays• Radiative penguin

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Inclusive CharmoniumInclusive Charmonium Decays Decays

Lepton identification • B-counting:

• Correct by (4S)

• 1.6% sys. Error

• 22,700,000 BB events

• Bremstrahlung-recovery for electrons• Background rejection: At least 3 tracks, Etot > 4.5 GeV Ratio of 2nd to 0th Fox-Wolfram moment R2 < 0.5

off

offMH

HMS N

NNNN )4(

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Inclusive Charmonium: J/Inclusive Charmonium: J/

• Inclusive branching ratio: Br(BJ/X) = (1.0440.013 0.028) 10-2

Br(BJ/X dir.) = (0.7890.010 0.034) 10-2

• J/ momentum distribution measured Y(4S) system = B system 250 MeV

• Polarization -0.4240.023 (-1 = longitudinal)• Signal from continuum subtracted ( …)

p*J/ < 2 GeV/c

J/ ll, l= e,

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• First observation of J/ production in continuum Rejection of BB (p*>2 GeV/c) Rejection of ISR (Ntracks, Etot, R2)

• Angular distribution: 1+A cos2*

• A (all E*) = 0.250.19 • A (p*>3.5 GeV) = 0.620.39

Color singles: A –0.8, 2.8 pb NDQCD (c.o): 0.6<A<1.0, 0.8 pb

J/J/ production in continuum production in continuum• 

mode resonance p* cut (GeV/c) yield

on >287952ee on >279962 off -15625ee off -12126

Not a B decay, but a new BaBar result…

.).%90(103.4

21.021.052.2

4/)4(

/

LCB

pb

XJS

XJee

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Inclusive Charmonium: Inclusive Charmonium: (2S)(2S)

p* < 1.6 GeV/c

(2S) ll, J/

• Br( B (2S) X ) = (0.2750.020 0.029) 10-

2

(2S) ll branching ratio

• Assuming PDG values for (2S) J/

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Inclusive Charmonium: Inclusive Charmonium: cc

• Br(B c1 X) = (0.378 0.034 0.026)10-2

• Br(B c1 X dir.) = (0.353 0.034 0.024)10-2

• Br(B c2 X) = (0.137 0.058 0.012)10-2

< 0.2110-2 @ 90% C.L.

c2 (?)c2 (?)

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Exclusive decaysExclusive decays

• Several CP channels sin2

• Direct CP asymmetry

• Kinematics selection: Energy substituted mass

• Independent on particle mass hypotheses

Energy difference in the center of mass

Example: BD0

2,4 cmBES p

sm

2

sEE B mES (GeV/c2)

E (

GeV

)

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BBJ/J/KK00SS

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BBJ/J/KK00LL

• KL reconstructed as neutral deposit in the IFR or E.M. Calorimeter

• 1.4 < p*J/ < 2.0 GeV/c

• No momentum measurement• E is measured

assuming the mB mass constraint

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Selected channelsSelected channels

First observation

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Branching rations resultsBranching rations results

Mode Br (10-4)

B0J/0 0.20.060.03

B0J/K*0 12.40.50.8

B+J/K* 13.70.91.1

B+J/K 10.00.30.5

B0J/KKL 6.80.80.8

B0J/KKS00 9.61.50.7

B0J/KKS+ 8.30.50.6

B0c1K* 4.81.50.9

B+c1K+ 5.11.41.3

B+(2S)K+ 6.10.50.8

B0(2S)K0 6.51.01.1

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BaBar compared to PDG 2000BaBar compared to PDG 2000

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J/J/++ / J/ / J/KK++

• Cabibbo and color suppressed tree diagram possible CP asymmetry from penguin contribution

• Unbinned maximum likelihood fit based on kinematical variables:

• Br(B+J/K)/(B+J/) =(3.910.78 0.19)10-2

0 2 4 6 8 10

Br(B+ to JpsiPi+) / Br(B+ to Jpsi K+)

CLEO

CDF

PDG

BaBar

( 5.2 2.4 ) %

( 5.0 0.1 ) %

+1.91.7

( 5.1 1.4 ) %

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J/J/ K* angular analysis K* angular analysis

Channels with 0

Channels without 0

• f (costr, cosK*, tr) = f1 |A0|2 + f2 |A|||2 + f3|A|2

f4 Im(A||* A) + f5 Re (A0* A||) + f6 Im (A0* A)

J/ rest frameK* decay plane

|A|2 + |A|||2 + |A0|2 = 1

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J/J/ K* angular analysis K* angular analysis

|A|2 = 0.1600.032 0.014 CP odd, P wave

|A|||2 = 0.2430.034 0.017 CP even, S+D wave

|A0|2 = 0.5970.028 0.024 CP even, S+D wave

= arg(A/A0)=0.170.16 0.07

|| = arg(A|| /A0)=2.500.20 0.08

CP asymmetry dilution factor: D = 1 – 2 |A|2 = 0.680.10

(a) Raw measurement(b) Acceptance correction(c) “ “ + mES fit(d) “ “ + (Self) Feed Across

Indication of FSI

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BBD*D*, D*, D*

• May exhibit small CP asymmetries • Potential for sin(2+) and

• Reconstruct the decay chains:

• B reconstruction efficiencies estimated with MC

*0 DB

0D

K

0D

K

*0 DB0

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Br(BD*+) = (2.9 ± 0.3 ± 0.3 ) 10-3

PDG: (2.76 ± 0.21) 10-3

BBD*D*

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Br(BD*+) = (11.2 ± 1.1 ± 2.5 ) 10- 3

PDG: (6.8 ± 3.4) 10-3

BBD*D*

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B B D* D*++D*D*

• Independent measurement of sin2• D*D0, D0 D0K, K, K, KS

D K, KS, KK

• B decays with two 0 are not used High background, low branching fraction

• Many possible combinations in the same event. Chosen the one which minimizes:

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B B D* D*++D*D*

Br(BD*+D*-) = (8.0 1.6 1.2)10-4

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B B D*D D*D((**))KK

• bccs transition• D*+ D0+; • D*0 D00

• D*0 D0• D0 K-+, • D0 K-+0 • D0 K-+-+; • D+ K-++;

• Br(B D*D0K) = (0.280.070.05)10-2

• Br(B D*D*K) = (0.680.170.17)10-2

• Br(B D*D*K) = (0.340.160.11)10-2

First observation of non-charmonium color suppressed mode

B0 (all modes)NS = 18021

B+ (all modes)NS = 11715

B D*D*K

NS = 8.23.5

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Charmless Hadronic DecaysCharmless Hadronic Decays

• Physics motivations

b u

d(s)Vub

Vud(s)

B0 { }

} (K)

d d

u

bB0 {

d

u

d(s)

}

} (K)

d

u

t

W

W

Vtb

Vtd(s)

Cabibbo suppressed

Penguin diagram

• Significant penguin contribution

• Direct CP violation studies

• Measurement of from time-dependent asymmetry + isospin analysis

• Possible field for new physics…

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Identifying K and Identifying K and

• Particle identification in the DIRC

D*+D0, D0K-+ control sample

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Background RejectionBackground Rejection

• Continuum events rejection Fisher discriminator on event shape Thrust axis (B vs rest of event)

• Background control samples E sidebands Off-resonance data D*+D0, D0K+ control sample

signal

  D0+

on reson. mES<5.26  

background

background

signal

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Two Body Charged ModesTwo Body Charged Modes

• Bhh

K

KK

Mode Yeld, significance

Branching ratio

K 16917+12-17, 15.8

(16.71.6+1.2-1.7)10–

6

41107, 4.7(4.11.00.7)10–6

KK 8.2+7.8–6.43.3, 1.3

<2.510–6 (90%C.L.)

UML Fit results

Cut based selection

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Two Body Charged + Neutral ModesTwo Body Charged + Neutral Modes

• B0h0+

0K+Mode Yeld, significance

Branching ratio

37+15-13, 3.4

(5.1+2.0-1.8 0.8)10–6

K 75+14-13, 8.0

(10.8+2.1-1.9

+1.0-1.2 )10–6

UML Fit results

Cut based projections

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BBKK00hh++,, KK0000

K0+

K0K+

K00Cut based projections

Mode Yield, significance

Branching ratio

K0 59+11-10, 9.8

(18.2+3.3-3.0

+1.6-2.0)10–6

K0K 0 (< 8), 0<2.610–6 (90%C.L.)

K00 17.9+6.8-5.8, 4.5

(8.2+3.1-2.7

+1.1-1.2)10–6

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Charge AsymmetriesCharge Asymmetries

• KA = - 0.190.100.03 [ -0.35, -0.03 ], 90%C.L.

• KA = 0.000.180.04 [ -0.30, +0.30 ], 90%C.L.

• KA = - 0.210.180.03 [ -0.51, +0.09 ], 90%C.L.

• All asymmetries compatible with 0 within current errors

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B+h+ < 24 10-6 ( 90% C.L. )

B0K0 < 14 10-6

B+K+ ( 62 18 8 ) 10-6

B0K0 < 112 10-6

B0K*0 < 28 10-6

B+0K+ < 39 10-6

B+0+ < 39 10-6

B+K+< 54 10-6

B++< 22 10-6

B0( 49 13+6-5 ) 10-6

Quasi 2-body and 3-body decaysQuasi 2-body and 3-body decays

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BBK, BK, BK* K*

• Penguin dominated • Measure of sin2

B+K+ = (7.7+1.6-1.40.8) 10-6

B0 K0 = (8.1+3.1-2.50.8) 10-6

B+ K*+ = (9.7+4.2-3.41.7) 10-6

B0 K*0 = (8.6+2.8-2.41.1) 10-6

B0 < 1.4 10-6 (90% C.L.)

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B B K* K*

Signal:

B0 K*0, K*0 K+-

Backgrounds:

e+e- qq

e+e- qq X 0

• Sensitive to top quark couplings CKM matrix elements

Vtd,Vts

• Sensitive to New Physics SUSY, Charged Higgs

• No CP asymmetry in the Standard Model Possible sources

beyond SM

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B B K* K*: yield and branching ratio: yield and branching ratio

• Nsignal = 139.2 13.1 events• Br(B0 K*0) = (4.39 0.41) 10-5

• Br(B K+e+e-) < 12.8 10-6

• Br(B K++-) < 8.3 10-6

• Br(B K*0e+e-) < 24.7 10-6

• Br(B K*0+-) < 25.7 10-6 (90% C.L.)

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B B K* K*: CP asymmetry: CP asymmetry

K*0

K*0

-

• K*0 K

• N(B0) = 72.1 9.4 events• N(B0) = 67.2 9.1 events

• ACP = -0.035 0.09

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bbss, B , B

• Semi-exclusive study Sum of exclusive modes

K+n(n=1,2,3)

• B(B0) < 1.94 x 10-6 90% C.L.• PDG: B(B0 ) < 3.9 x 10-5 90% C.L. (from L3)

mES for 0.6 <mhad < 2.0 GeV

668 53 events

PRELIMINARY

PRELIMINARY

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ConclusionsConclusions

• Many branching ratios have been measured in BaBar

• Some are newly observed signals• Potential for more CP violation studies• More statistics will permit to measure CP

asymmetries

• Stay tuned!