Results of BABAR experiment
on CP violation and B physics
L.Lista
INFN Sezione di Napoli
Napoli, 20/6/01
Luca Lista
Outline
• Experimental set-up
• Charmonium decays
• B lifetime measurement
• Mixing and CP asymmetry
• Rare B decays
• Future perspective and
Conclusions
Napoli, 20/6/01
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(4S)
The PEP-II B-Factory
center of mass energy
 MU(4S) =10.58 GeV/c2
bg = 0.56
at Stanford Linear
Accelerator Center (California)
Low Energy Ring
[e+, 3.1GeV]
BaBar
High Energy Ring
[e-, 9.0GeV]
Has delivered 23.7 fb-1 from Oct. 99 to Nov.2000
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Performance during the 99-00 run
Parameter
Design
# of bunches
1658
LER current
2.14 A
HER current
0.75 A
Achieved
1658
2.14 A
0.92 A
Typical
553-829
1.35 A
0.73 A
Beam size x
Beam size y
222 m
6.7 m
190 m
6.0 m
-
Fill time
Top-off time
6 mn
3 mn
8 mn
2 mn
10 mn
3 mn
LER lifetime
HER lifetime
4 hrs@2A
4 hrs@1A
3.3 [email protected]
11. [email protected]
3.0 [email protected]
9.0 [email protected]
Luminosity
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3.0 1033 cm-2s-1 3.3 1033 cm-2s-1 2.5 1033 cm-2s-1
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The BaBar detector
Electromagnetic
Calorimeter
6580 CsI(Tl) crystals
1.5T solenoid
e+
DIRC (PID)
144 quartz bars
11000 PMTs
Drift Chamber
40 axial stereo
layers
e-
Instrumented Flux Return
19 iron / 18-19 RPC layers
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Silicon Vertex Tracker
5 layers, 2-sided Si strips
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The Silicon Vertex Tracker
Beam bending magnets
high radiation area
Beam pipe
layer 1,2
layer 3
layer 4
layer 5
• 5 layers: 20o<  <150o;
R= 3.2, 4, 5.4, 9.1-12.7, 11.4-14.4 cm
• Single hit resolution: 10-15 m
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The Drift Chamber
(pT)/pT =
0.13%  pT  0.45%
• 40 axial and stereo layers for Z measurement
• small hexagonal cells (11.9 x 19.0 mm)
• 80%:20% helium:isobutane
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The Cherenkov detector (DIRC)
• Internally reflected
Cherenkov radiation
• ~11000 phototubes
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The Electromagnetic Calorimeter
• Identification of e±,g,p0
• Energy resolution:
 (E)
E
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2.3%
 4
 1.9%
E
The Instrumented Flux Return
Muon and KL
reconstruction
18/19 RPC planes
~53000 electronic
channels
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B-counting
• The determination of B decays branching
ratios requires a precise estimate of the
number of produced (4S)BB events
• Counting of Multi-Hadron events
off
N MH
N BB  N MH  N  off 
N 
• Correction factor:  = 0.99620.0027
 Different efficiencies for  and MH on and offresonance
• 22,700,000 BB events, 1.7% sys. error
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b
c
c
W-
B0, B
J/, (2S), c
Efficiency
Inclusive Charmonium Decays
s, d
X
• J/, (2S) and c are
reconstructed in final states
containing leptons
• Different selection purity for
different decays
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Efficiency
d, u
muons
pions
Inclusive J/ decays
p*J/ < 2 GeV/c
J/ +
J/ e+e
• Inclusive branching ratio:
Br(BJ/X)
= (1.0440.013 0.028)  10-2
Br(BJ/X dir.) = (0.7890.010 0.034)  10-2
• p*: J/ momentum distribution in the (4S) system
 B system coincides with (4S) within 250 MeV
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J/ momentum spectrum
BB events
continuum
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J/ production in continuum
• First observation of J/ production in
continuum
 BB events rejected by p*>2 GeV/c
 Rejection of Initial State Radiation
• Ntracks, Etot, R2
Angular distribution
1+A cos2*
e e
+ 
 J /X
 2.52  0.21  0.21 pb
BU ( 4 S ) J /X  4.3  104 (90%C.L.)
• A (all E*)
= 0.250.19
• A (p*>3.5 GeV) l= 0.620.39
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 Color singles prediction: A  –0.8,
  0.8 pb
 NRQCD (c.o.) prediction: 0.6<A<1.0,   2.8 pb
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Inclusive (2S) decays
(2S) l+l, J/p+p
Br( B (2S) X ) =
(0.2750.020 0.029) 10-2
p* < 1.6 GeV/c
• (2S)  l+l branching
ratio measurement
• Assuming PDG values for
(2S)  J/p+p:
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(2S)  e+e
(8.1  0.9  0.9)10-3
(2S)  +
(7.0  0.8  0.9)10-3
Inclusive c decays
c2 (?)
c2 (?)
• 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)
< 0.2110-2 @ 90% C.L.
= ( 0.137  0.058  0.012 )  10-2
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Exclusive B decays
• Motivation:
• Kinematics selection:
 Several channels are used
to constrain the unitarity
triangle
 Charged modes may
exhibit direct CP
asymmetry
 Probe of non perturbative
QCD
 Theoretical prediction
available for many decays
in the factorization
hypothesis
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 Energy substituted mass
mES 
s
 pB2 ,cm
4
• Independent on particle
mass hypotheses
 Energy difference
in the center of mass
s
E  E B 
2
Golden CP mode: BJ/K0S
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BJ/K0L
• KL reconstructed as neutral
deposit in the I.F.R. or E.M.
Calorimeter
• 1.4 < p*J/ < 2.0 GeV/c
• No KL momentum
measurement
•
E is determined
assuming the mB
mass constraint
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Selected rare channels
B0J/
Napoli, 20/6/01
First observation:
B0C1 K*0
p0
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Branching ratios results
Mode
Br (10-4)
B0  J/ p0
0.20  0.06  0.02
B0  J/ K*0
12.4  0.5  0.9
B+  J/ K*+
13.7  0.9  1.1
B+  J/ K+
10.1  0.3  0.5
B0  J/ K0 (KL)
6.8  0.8  0.8
B0  J/ K0 (KSp0p0)
9.6  1.5  0.7
B0  J/ K0 (KSp+p)
8.5  0.5  0.6
B0  J/ K0 (All)
8.3  0.4  0.5
B0  c1 K*0
4.8  1.4  0.9
B0  c1 K0
5.4  1.4  1.1
B+  c1 K+
7.5  0.8  0.8
B+  (2S) K+
6.3  0.5  0.8
B0  (2S) K0
6.8  1.0  1.1
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BaBar compared to PDG 2000
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J/p+ / J/K+
• Cabibbo and color suppressed tree diagram
 possible CP asymmetry from penguin contribution
• Unbinned maximum likelihood fit based on kinematical
variables:
Br(B+J/p+)/Br(B+J/K +) =(3.910.78 0.19)10-2
( 5.2  2.4 ) %
CLEO
CDF
PDG
BaBar
( 5.0 +1.9  0.1 ) %
1.7
( 5.1  1.4 ) %
0
2
4
6
Br(B+ to JpsiPi+) / Br(B+ to Jpsi K+)
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8
10
B± and B0/B0 lifetimes
• One B is fully reconstructed
• Novel method for
in a B0 or B mode
asymmetric e+e- machines
• Measure both B vertices
• Different systematics from
• Fit for t @ z/c gBU b gUlab
previous measurements
ideally PDF(t)  exp(-|t|/tB) • Detailed understanding of
resolution function needed
B1 partially reconstructed
z ~ 140 m
B2 fully reconstructed
z ~ 60-100 m
Z
e- e+
9 GeV
3.1GeV
bg = 0.56
Napoli, 20/6/01
z
gbctB @ 260 m
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The 99-00 data sample
22.7 106 BB pairs recorded
B
B0/B0
B0  D(*)+ p D(*)+D(*)+a1J/K*0
B-  D(*)0 p J/ K(2S)K-
6967 ± 95
purity  90%
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7266 ± 94
purity  93%
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Fitting procedure
B0/B0 MC
Resolution function fitted on data:
R(t)=f*Gaus(s)+(1-f)*Gaus(s)Exp(k)
identical for B± and B0/ B0
t residual/ t
psig from mass
distribution fit
Unbinned maximum likelihood fit:
 t / t
B
P.d.f. ( t )  psig  e
 Rsig ( t )
 t / t bgd
+ pbgd  [( a ( t ) + be
)  Rbgd ( t )
+ cO(t )]
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Bkg description from
side-band events
Lifetime results
B
B0/B0
background
preliminary
t (ps)
t (ps)
t0 = 1.546  0.032(stat)  0.022(syst) ps
t  = 1.673  0.032(stat)  0.022(syst) ps
t0 /t = 1.082  0.026(stat)  0.011(syst)
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common resolution
Other lifetime ratio measurements
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The Unitarity Triangle
d
s
u  Vud

c  Vcd


t  Vtd
Vus
Vcs
Vts
b
Vub 

Vcb 


Vtb 
• Quark mixing is described
by the CKM matrix
• Unitarity relations on matrix
elements lead to a triangle
in the complex plane
A=(,)
*
ud ub
*
cd cb
VV
VV
*
*
VudVub
+ VcdVcb
+ VtdVtb*  0

g
C=(0,0)
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VtdVtb*
VcdVcb*
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b
1
B=(1,0)
CP violation at asymmetric B factory
CP violation via mixing interference in bccs
B0
J/K0s
B0
B0
b
d
t
W
W
t
d
0
B
b
@t=0
 t / t B
[1  CP sin 2 b sin( md t )]
F+CP ( t )  FCP ( t )
ACP ( t )  CP
F+ ( t ) + FCP ( t )
 CP sin 2 b sin( md t )
Integrated asymmetry = 0
time dependent analysis required
B0
B0
F
FCP ( t )  e
F+
t (ps)
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• coherent production:
Y(4S)  BB
 clock starts at
1st B decay
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The 99-00 data sample: CP modes
J/K0S (p+p)
425 ± 22
purity  94%
J/K0S (p0p0)
(2S)K0S (p+p)
J/K0L
CP = +1
199 ± 23
purity  45%
Napoli, 20/6/01
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CP = -1
Mixing and CP asymmetry of B0/B0
B01 partially reconstructed
flavour tagged
B02 fully reconstructed
D*+ p - or J/K0S
e-e+
z
B1 = B0
CP modes: FCP(t)  e-|t|/tB ( 1  CP sin2b . sin md t )
B1 = B0
unmixed B0 B0
Flavour specific modes:
Fflav(t)  e-|t|/tB ( 1  cos md t )
mixed B0B0 or B0B0
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Tagging the flavour of the B0CP/flav
• leptons: b  l- , b  l+
Look at the second B in the event
p*>1.0 GeV/c (e±), p*>1.1 GeV/c (±)
e = 10.9  0.4%
b  K- , b  K+
e = 36.5  0.7%
Neural network mainly to
recover unidentified leptons
and use soft pions from D*
• NT1:
e = 7.7  0.4%
• NT2:
e = 13.7  0.5%
Total e = 68.9  1.0%
• kaons:
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Imperfect tagging and resolution
perfect tagging/
resolution
imperfect tagging/
perfect resolution
imperfect tagging/
imperfect resolution
B0
B0
e-|t|/tB (1 CP sin2b
 sin md t)
e-|t|/tB (1 CP D sin2b
sin md t)
e-|t|/tB (1 CP D sin2b
 sin md t)  R(t)
unmixed
mixed
e-|t|/tB (1 cos mdt)
Napoli, 20/6/01
e-|t|/tB (1 D cos md t)
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e-|t|/tB (1 D cos mdt)
 R(t)
Fitting Procedure
unbinned maximum likelihood fit:
• md : flavour specific sample
• sin2b : flavour specific +CP samples
Free parameters #par
sample
Mainly
constrained
by high stat
flavour
sample
sin2b
1
CP
md
1
flavour
D(B ) & D(B )
8
flavour & CP
Sig. t resolution
9
flavour & CP
largest
correlation
with sin2b:
7.6%
Bkg. t resolution
3
flav & CP side-bands
Bkg. composition
13
Bkg. composition
1
0
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0
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Empirical
description
fitted on data
flavour side-bands
CP side-bands
Flavour misid. measurement
Tag
leptons
kaons
NT1
NT2
total
w (%) Q=e(1-2w)2 (%)
11.6  2.0
6.4  0.7
17.1  1.3 15.8  1.3
21.2  2.9
2.6  0.5
31.7  2.6
1.8  0.5
26.7  1.6
leptons
Napoli, 20/6/01
Fraction of
wrongly tagged
events
(sin2b)  1/(Q)
Check w with a time-integrated method
(events with |t|<2.5 ps to optimise (w))
On the same sample and on ~11000 D*ln
NT2
NT1
D=1-2w
kaon
s
Tag
leptons
kaons
NT1
NT2
hadronic sample
11.8  2.1  0.7
17.7  1.4  0.8
19.7  3.0  1.1
32.3  2.7  1.1
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semileptonic
10.3  1.4  1.1
18.7  0.9  1.3
22.5  2.1  2.0
38.2  1.7  1.5
md measurement
preliminary
md =
0.519 ±0.020stat±0.016syst ps-1
e-|t|/tB (1 D cos mdt)  R(t)
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md measurement: the di-lepton analysis
e-e+
l+or l-
Asymmetry
z
A(z)=
l+or l-
N+ –, – + – N+ +, – –
N+ –, – + + N+ +, – –
md = 0.499 ± 0.010 ± 0.012 ps-1
Napoli, 20/6/01
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preliminary
preliminary
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sin2b results
sin2b=0.87±0.51stat
sin2b=0.25±0.22stat
sin2b = 0.34 ± 0.20stat ± 0.05syst
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Time dependent asymmetry
sin2b=0.25±0.22stat
CP = +1
ln(L/Lmax)
CP = -1
sin2b=0.87±0.51stat
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sin2b
combined result
Cross-checks: sin2b on sub-samples
sin2b
Napoli, 20/6/01
sin2b
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sin2b systematic uncertainties
Napoli, 20/6/01
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World average for sin2b
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Unitarity triangle
sin2b =
0.34 ± 0.20stat ± 0.05syst
1
2
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J/ K*0 angular analysis
• L=0,1,2 waves
• Both CP even and odd amplitudes are present
• Measurement of sin2b is possible
from angular analysis
Channels without p0
Channels with p0
J/ rest frame
K* decay plane
f (costr, cosK*, tr) = f1 |A0|2 + f2 |A|||2 + f3|A|2
f4 Im(A||* A) + f5 Re (A0* A||) + f6 Im (A0* A)
|A|2 + |A|||2 + |A0|2 = 1
Napoli, 20/6/01
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J/ K* angular analysis
|A|2 = 0.1600.032  0.014
CP odd, P wave
|A|||2 = 0.2430.034  0.017
CP even, S+D wave
|A0|2 = 0.5970.028  0.024
CP even, S+D wave
 = arg(A/A0)=0.170.16 0.07
|| = arg(A|| /A0)=2.500.20 0.08
Indication of FSI
(a) Raw measurement
(b) Acceptance correction
(c) “ “ + mES fit
(d) “ “ + (Self) Feed Across
Time dependent CP asymmetry
dilution factor:
D = 1 – 2 |A|2 = 0.680.10
Napoli, 20/6/01
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B  D*D(*)K
• Study of the bccs transition
Color suppressed
Color allowed
• Experimental inclusive estimate from from
BDSX, (cc)X, CX, CX (ALEPH, CLEO)
 Br(bccs) ~ 15.82.8 %
• Theoretical calculation can’t determine this low value
together with inclusive s.l. branching ratio (bcW)
 Three-body B  DDK can contribute
• Study of color suppressed modes (B+ D*+D*K+)
Napoli, 20/6/01
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B  D*D(*)K
• Reconstructed
decays:







D*+ D0p+
D*0 D0p0
D*0 D0g
D0 K-p+
D0 K-p+p0
D0 K-p+p-p+
D+ K-p+p+
B+ (all modes)
NS = 11715
• Br(B0 D*+D0K+) = (0.280.070.05)10-2
• Br(B0 D*+D*0K+) = (0.680.170.17)10-2
• Br(B+ D*+D*K+) = (0.340.160.11)10-2
 First observation of color suppressed
mode other than B  (charmonium)X
Napoli, 20/6/01
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B0 (all modes)
NS = 18021
B+ D*+D*K+
NS = 8.23.5
B0  D*+D*
• Cabibbo suppressed decay
• A measurement in bccd of CP
violating time-dependent asymmetry can
be performed from angular analysis
 Possible penguin contamination
Tree diagram
• Measurement of sin2b independent from
B0J/K0S
 Significant deviations from B0J/K0S
measurement of sin2b may be indication
of new physics
Penguin contribution
• Branching ration measurement of B  D(*)+D(*)-:
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B0  D*+D*
Signal box
(38 events)
Background sample
(6.240.49 expected in signal box)
Br(B0D*+D*-) = (8.0  1.6  1.2)10-4
Napoli, 20/6/01
Luca Lista
Charmless Hadronic Decays
• Physics motivations
Vud(s)
B0
b
{d
Vub W

u
d(s)
u
d
} p (K )
}p


+
Cabibbo suppressed tree diagram
B0
b
{d
W Vtd(s)
Vtb
t
}
}
u
p(K)
d(s)
u
p+
d
Penguin diagram
Napoli, 20/6/01
• Significant penguin
contribution
• Direct CP violation
studies
• Measurement of  from
time-dependent
asymmetry + isospin
analysis
• Possible field for new
physics…
Luca Lista
Identifying K and p
• Particle identification in the DIRC
> 3 sigma
p (GeV/c)
p (GeV/c)
D*p+D0, D0K-p+ control sample
Napoli, 20/6/01
Luca Lista
Background Rejection
• Continuum events rejection
 Combination of event shape variables
 Thrust axes (B vs rest of event)
• Background control samples
 E sidebands
 Off-resonance data
 D*p+D0, D0Kp+ control sample
background
signal
Napoli, 20/6/01
Luca Lista
background
 D0p+
 E sidbands
signal
Two Body Charged Modes
Fit projections
(after a likelihood ratio cut)
• B  h+ h
Unbinned Maximum Likelihood
Fit results
K+p
p+p
Mode Yield, significance
Branching ratio
K+p
169  17+12-17, 15.8
(16.7  1.6 +1.2-1.7)10–6
p +p 
41  10  7, 4.7
(4.1  1.0  0.7)10–6
K+K 8.2 +7.8–6.4  3.3, 1.3
< 2.510–6 (90%C.L.)
Napoli, 20/6/01
mES (GeV/c2)
Luca Lista
E (GeV)
Two Body Charged + Neutral Modes
• B  p0 h+
Fit projections
Unbinned Maximum Likelihood
Fit results
Mode
Yield, significance
Branching ratio
p0 p+
37 +15-13, 3.4
(5.1+2.0-1.8  0.8)10–6
p0 K+
75 +14-13, 8.0
(10.8 +2.1-1.9 +1.0-1.2 )10–6
mES (GeV/c2)
Napoli, 20/6/01
Luca Lista
E (GeV)
Two Body with K-short
• B  K0h+, K0p0
Fit projections
Unbinned Maximum Likelihood
Fit results
Mode
Yield, significance
Branching ratio
K0p+
59 +11-10, 9.8
(18.2 +3.3-3.0 +1.6-2.0)10–6
K0K+
0 (< 8), 0
< 2.610–6 (90%C.L.)
K0p0
17.9 +6.8-5.8, 4.5
(8.2 +3.1-2.7 +1.1-1.2)10–6
Napoli, 20/6/01
mES (GeV/c2)
Luca Lista
E (GeV)
Direct CP Asymmetries
• Self tagged modes:
• K+p
• K+p0
• K0p
A = - 0.19  0.10  0.03
[ -0.35, -0.03 ], 90%C.L.
A = 0.00  0.18  0.04
[ -0.30, +0.30 ], 90%C.L.
A = - 0.21  0.18  0.03
[ -0.51, +0.09 ], 90%C.L.
• All asymmetries compatible with 0 within
current errors
Napoli, 20/6/01
Luca Lista
Quasi 2-body and 3-body decays
B+h+
B0K0
B+K+
B0K0
< 24  10-6 ( 90% C.L. )
< 14  10-6
( 62  18  8 )  10-6
< 112  10-6
B0K*0 p+
B+0K+
B+0p+
B+K+p+p
B+p+p+p
B0p
< 28  10-6
< 39  10-6
< 39  10-6
< 54  10-6
< 22  10-6
( 49  13 +6-5 )  10-6
Napoli, 20/6/01
Luca Lista
B0p
BK, BK*
• Penguin dominated
Max Lik. Fit projections
B+K+
= (7.7 +1.6-1.4  0.8)  10-6
B+ p+
< 1.4  10-6 (90% C.L.)
B+ K*+
= (9.7 +4.2-3.4  1.7)  10-6
• Possible measure of sin2b:
B0 K*0
= (8.6 +2.8-2.4  1.1)  10-6
B0 K0
= (8.1 +3.1-2.5  0.8)  10-6
Napoli, 20/6/01
Luca Lista
Radiative Penguin: B  K*g
Signal:
• Sensitive to top quark
couplings
 CKM matrix elements
Vtd,Vts
• Sensitive to New
Physics
 SUSY, Charged Higgs
• No CP asymmetry in the
Standard Model (< 1%)
 Possible sources
beyond SM
Napoli, 20/6/01
B0  K*0g,
K*0  K+pBackgrounds:
e+e-  qq g
e+e-  qq  X p0
Luca Lista
B0  K*0g: yield and branching ratio
B0  K*0g
K*0  K+p
• Nsignal = 139.2  13.1 events
• Br(B0  K*0g) = (4.39  0.41  0.27)  10-5
•
•
•
•
Br(B  K+e+e-)
Br(B  K++-)
Br(B  K*0e+e-)
Br(B  K*0+-)
< 12.8  10-6
< 8.3  10-6
< 24.7  10-6
< 25.7  10-6 (90% C.L.)
Napoli, 20/6/01
Luca Lista
B0  K*0g: CP asymmetry
• K*0 K+p, K*0 Kp+
B  K g  ASM + ANEW ei s ei w
K*0 g

B  K g  ASM + ANEW ei s e i w
ACP 
2

2
2

2
BK g  BK g

BK g + BK g

K*0 g
A
 NEW sin  s sin  w
ASM
• N(B0) = 72.1  9.4 events
• N(B0) = 67.2  9.1 events
• ACP = -0.035  0.094  0.022
Napoli, 20/6/01
-
Luca Lista
bsg, B0  gg
•
mES for 0.6 <mhad < 2.0 GeV
Semi-exclusive study
 Sum of exclusive modes
K+np (n=1,2,3)
B0  gg
Napoli, 20/6/01
Branching ratio measurement
coming soon…
• Theoretical exp.: ~ 108
• Br(B0gg) < 1.94 x 10-6 90% C.L.
• PDG: Br(B0 gg) < 3.9 x 10-5 90% C.L. (L3)
Luca Lista
Future
• more sin2b modes in
preparation (J/K*, cKs,...)
• Run 2 has started in Feb.
2001 and should be ended
in June 2002.
Run1 + Run2  100 fb-1
• studies of decay modes
for other unitarity angles 
and g analysis started
Napoli, 20/6/01
Luca Lista
Conclusions (I)
• From Oct. 99 to Nov. 2000, BaBar has recorded
22.7 106 BB pairs and a large sample of
hadronic B decays has been fully reconstructed.
• High precision measurements of neutral/charged
B lifetimes:
t0 = 1.546  0.032stat  0.022syst ps
t = 1.673  0.032stat  0.022syst ps
t0 /t = 1.082  0.026stat  0.011syst
• competitive result on mixing parameter md:
md = 0.519 ± 0.020 ± 0.016 ps-1
• sin2b was extracted from ~500 CP mode events:
sin2b = 0.34 ± 0.20stat ± 0.05syst
Napoli, 20/6/01
Luca Lista
Conclusions (II)
• First evidence of charmonium production in continuum
• Precise measurements of exclusive charmonium decays
 First observation of B0C1 K*0:
Br(B0  c1 K*0) = 4.8  1.4  0.9
• First observation of color suppressed mode:
 Br(B+ D*+D*K+) = (0.340.160.11)10-2
• Measurements of charmless 2-body decays:




Br(B0  K+p) =(16.7  1.6 +1.2-1.7)10–6
Br(B0  p+p) =(4.1  1.0  0.7)10–6
Br(B+  p0p) =(5.1+2.0-1.8  0.8)10–6
Br(B+  p0K) =(10.8 +2.1-1.9 +1.0-1.2 )10–6
• Radiative penguin decay:
 Br(B0  K*0g) = (4.39  0.41  0.27)  10-5
ACP = -0.035  0.094  0.022
• More statistics will permit to measure to improve the current
measurements and to access more rare channels!
Napoli, 20/6/01
Luca Lista