1. B decays to open charm and charmonium from BaBar
Stefania Ricciardi
Royal Holloway, University of London
On behalf of the BaBar Collaboration
32nd International Conference on High Energy Physics Beijing, August 16-22nd,2004

2. Stefania Ricciardi, BaBar
Outline
Testing models of hadronic B decays
Inclusive charm production in B decays
B0  Ds*+ D*- [and Ds  f p+]
B0  D(*)-pp+, B0  D(*) 0pp
Exclusive B  (cc) K(*), where cc = J/y,y(2S),cc
Charm and Charmonium Spectroscopy:
B decays to DsJ (2317) and DsJ (2460)
X(3872)
For new results on B D(*)K(*) and B Ds+r -
see L.Cavoto’s talk in the CP violation session
All results are PRELIMINARY
Fully hadronic decays of B mesons provide an effective laboratory to test heavy quark theories and
study dynamics of strong interactions in heavy meson systems
Stefania Ricciardi, BaBar
ICHEP04

3. Stefania Ricciardi, BaBar
Inclusive charm
Hadronization models (Heavy Quark Expansion)
predict average charm multiplicity
in B decays, nc 
[Bagan et al. PLB351(1995)
Buchalla and Dunietz, PLB364(1995)
Neubert and Sachrajda, Nucl.Phys.B483(1997)] b c u
W - B- s’
We define:
Flavor correlated charm
production from dominant
bc transition
Flavor anti-correlated charm
production from W-  cs’ decay
The dominant process for the decay of a b quark is a b->c transition , resulting in a flavor correlated c quark and a W. The decay of a W in cs or cd pair will produce anti-correlated charm
[charge-conjugation
implied everywhere]
Stefania Ricciardi, BaBar
ICHEP04

4. Inclusive charm: a new experimental method
Full reconstruction of one B = Breco
Charm hadron searched for in rest of event, fully reconstructed
and correlated with charge of parent B = Brecoil
We correct for: mixing in the B0 sample
and background from B0 (B+) in the B+ (B0) sample K D0
Breco
Y(4S) B B : p B+
(#)
Y(4S)
p, r,a1 e- e+
D+, D0, Ds,Lc B-   X
Brecoil
(# at the time of Breco
decay only, for neutral B)
Stefania Ricciardi, BaBar
ICHEP04

5. Stefania Ricciardi, BaBar
BaBar Preliminary
Inclusive charm D0 D0
Signal
127342
Signal
16016
Data sample: 89 million B pairs D+
Blue-shaded areas:
true charm particles
from background of
misreconstructed B
Signal
26229
Signal
9820 D-
B- anti-correlated
D+S
Signal
115
D-S
Signal
8211
B- correlated
Significant production of
correlated D0 and D+
Ds correlated
production small.
Anti-correlated dominant.
L+c
Signal
419
L-c
Signal
339
Stefania Ricciardi, BaBar
ICHEP04

6. Inclusive charm: branching fraction
correlated
anti-correlated Xc
B(B- XcX) % D0
79.3 ± 2.5 ±
9.8 ± 0.9 ± D+
9.8 ± 1.2 ±
3.8 ± 0.9 ±
D+s
0.5 ± 0.6 ±
<2.2 at 90% CL
14.3 ± 1.6 ±
L+c
3.5 ± 0.8 ±
2.9 ± 0.8 ±
B- recoil
N(B+RECO) = ± 1910
correlated
anti-correlated Xc
B(B- XcX) % D0
51.1 ± 3.1 ±
6.3 ± 1.9 ± D+
39.7 ± 3.0 ±
2.3 ± 1.8 ±
< 5.1 at 90% CL
D+s
3.9 ± 1.7 ±
< 8.7 at 90% CL
10.9 ± 2.1 ±
L+c
4.9 ± 1.7 ±
2.0 ± 1.2 ±
<3.9 at 90%CL
B0 recoil
N(B0RECO) = ± 590
First measurement of
D+s correlated
Sizeable Lc
production
Stefania Ricciardi, BaBar
ICHEP04

7. Inclusive charm: nc0, nc-
We find no evidence of
B- Lc+ Lc- K
looking at the missing mass distribution (obtained from the
B 4-momentum, a K and a reconstructed Lc or Lc)
We estimate
B(B- c X) = B(B- Lc- X) - B(B- Lc+ Lc- K)  B(B- Lc- X)
B(B- c X) neglected
Using B(B- (cc) X) = (2.3 ± 0.3) %,
we determine separately for the first time: B- B0
Previous results (hep-ex/ )
1.175 ± (CLEO)
1.230 ± (LEP+SLD)
1.206 ± (Average)
Stefania Ricciardi, BaBar
ICHEP04

8. Stefania Ricciardi, BaBar
B0  Ds*+ D*-
New measurement of B(B0  Ds*+ D*-)
Experimental test of factorization at high q2 values: q2~m2(Ds*+)
New measurement of B(Ds+ f p+)
used to normalize other Ds+ branching fractions
The present ~25% uncertainty
B (Ds+f p+ ) = (3.6 ± 0.9)% (CLEO)
propagates to all analyses where a Ds(*) is reconstructed
Stefania Ricciardi, BaBar
ICHEP04

9. Stefania Ricciardi, BaBar
B0  Ds*+ D*-: method
With a partial reconstruction technique, determine
B1 = B (B0  Ds*+ D*-)
Fully reconstruct final state with Ds+ f p+ and measure
B2 = B (B0  Ds*+ D*-) x B (Ds+ f p+)
B (Ds+ f p+) = B2/B1.
Many systematics cancel in the ratio.
Stefania Ricciardi, BaBar
ICHEP04

10. B0  Ds*+ D*- : partial reconstruction
hep-ex/
124 million B pairs
Ds+ from Ds*+  Ds+ is not reconstructed
Pair D*- ( D0 p-) and  , assuming they
come from B0 Ds*+D*-
This BaBar Result
independent of B(Ds+ fp+) :
Signal: 7414 ± 345
B(B0 Ds*+D*-) = (1.85 ± 0.09(stat) ± 0.16(syst) )%
in agreement with previous:
and theory (Luo and Rosner,2001):
We compute the missing mass recoiling against the D* - gamma system in the center of mass
The distribution of signal events peak at the nomial D-S mass with a spread of about 15MeV   
B(B0 Ds*+D*-) = (1.9 ± 0.5)% (PDG2004)
B(B0 Ds*+D*-) theor= (2.4 ± 0.7)%
Stefania Ricciardi, BaBar
ICHEP04

11. Stefania Ricciardi, BaBar
Ds+ f p+ :Results
D* and g selection analogous to inclusive analysis
Ds+ f (K+K-) p+ fully reconstructed
measure branching fraction product:
B (B0  Ds*+ D*-) x B (Ds+ f p+) = (8.71  0.78(stat)) x10-4
Dividing by our measurement of
B(B0 Ds*+D*-), we obtain
B(Ds+ f p+) = (4.71 ± 0.47(stat) ±0.35(syst))%
to be compared with
Signal 212 ±19
B(Ds+ f p+) = (3.6 ± 0.9)% (CLEO)
Readjustment of many results needed!
Not used yet for other results in this talk
Stefania Ricciardi, BaBar
ICHEP04

12. B0D(*)-pp+ and B0 D(*)0pp
hep-ex/
124 millions B pairs
B0D(*)-pp+ and B0 D(*)0pp
Full reconstruction
Explore dynamics of decays
involving baryons
Multi-body decays to baryons
sizeable, as found by CLEO
& predicted
B0D*-pp+
130 ± 14
B0D-pp+
238 ± 22
I.Dunitez, PRD (1998)
Hou and Soni, PRL (2001)
Chua, Hou and Tsai, PRD (2002)
B0D*0pp
13 ± 4
B0D0pp
96 ± 11
No evidence of 3.1 GeV
Sizeable means few times lower than D*pi, Drho
Dunietz predicts total baryon production and subtracts charmed baryon production
to determine B->D*NN X where N is a nucleon (prediction = few %)
Chua et al use a factorization approach of current produced nucleon pairs (baryon weak current form factors related by isospn rotation to nucleon em form factors (account of 60% of observed rate, rest from axial currents).
B0D*-pp+
Decay
B (10-4)
Reference B (10-4)
B0D*-pp+
5.61 ± ± 0.73
± 1.0 (CLEO)
B0D-pp+
3.80 ± ± 0.46 -
B0D*0pp
0.67 ± ± 0.09
± 0.21 (Belle)
B0D0pp
1.24 ± ± 0.12
1.18 ± ± 0.16 (Belle)
Stefania Ricciardi, BaBar
ICHEP04

13. Stefania Ricciardi, BaBar
B  (cc) K(*)
Exploring heavy quark dynamics by measurements of exclusive B decay rates to modes allowed in the factorization scheme
(charmonium JPC=1-- or 1++) [12 decay modes]:
B  J/y K(*)
B  y(2S) K(*)
B  cc1 K(*)
and suppressed ( measure size of non-factorizable contributions)
(JPC=0++ or 2++) [8 decay modes]:
B  cc0 K(*)
B  cc2 K(*)
Measurement of CP asymmetries
in the charged modes to search
for effects due to “New Physics”
[Diehl and Hiller, JHEP 0106 (2001)]
Charmonium reconstructed in
J/y(y(2S))  l+l-
cc J/y
Stefania Ricciardi, BaBar
ICHEP04

14. B (B  (cc) K(*)) Results
hep-ex/
124 million B pairs
Channel BR (10-4) PDG2004
B+  J/y K  0.15   0.4
B+  cc1 K*+
B0  J/y K  0.23   0.5
B+  J/y K*  0.36   1.0
B0  J/ y K*  0.25   0.7
B+  y (2S) K  0.33   0.4
B0  y(2S) K  0.60   0.7
B0  cc1 K*0
B+  y (2S) K*  0.85   2.2
B0  y (2S) K*  0.57   1.3
B+  cc1 K  0.24   1.2
B0  cc1 K  0.39 
B+  cc1 K*  0.69  new
B0  cc1 K*  0.37   1.5
Stefania Ricciardi, BaBar
ICHEP04

15. B  (cc) K(*): Other Results
Charged/Neutral Ratio
assuming equal production of charged and neutral at Y(4S) (i.e., R+/0 =1)
R+/0 (assuming isospin invariance and tB+/ tB0=1.086 ± from PDG2004)
Final state
Asymmetry
J/y K+
± ± 0.010
J/y K*+
0.045 ± ± 0.011
y(2S)K+
0.059 ± 0.051± 0.021
y(2S)K*+
± ± 0.050
cc1 K+
0.011 ± ± 0.017
cc1 K*+
± ± 0.237
Charge CP Asymmetries
All measurements compatible with
no direct CP asymmetry.
Stefania Ricciardi, BaBar
ICHEP04

16. Factorization suppressed decays
hep-ex/
124 million B pairs
B+  cc0 ( pp,KK) K+ observed by Belle and BaBar with B.F. >10-4, i.e., comparable to factorization allowed decays
Radiative BF relatively large for cc2:
B (cc0  J/y g) = (1.18 ± 0.14)%
B (cc1  J/y g) = (31.6 ± 3.3)%
B (cc2  J/y g) = (20.2 ± 1.7)%
cc2
BF (10-4)
(90% CL) K+
<0.36 K0
<0.44
K*+
<0.14
K*0
<0.22
m(llg) – m(ll)
cc1
cc1
cc2
cc2
cc0
cc0
Upper limits for B  cc2 K(*)
an order of magnitude smaller
than B.F. for factorization
allowed modes and B  cc0 K(*)
No statistical significant signal
Stefania Ricciardi, BaBar
ICHEP04

17. B Mesons Heavenly Gateways to Forbidden States…
Spectroscopy
B Mesons
Heavenly Gateways
to Forbidden States…
B mesons are a privilege gateway to study the nature of newly discovered puzzling particles
and search for new levels in the charm and charmonium spectra.

18. Study of B  DsJ(*)+D(*)
DsJ*(2317)+, DsJ (2460)+
Observed by BaBar, Belle and CLEO
Unexpectedly below threshold for DK and D*K, respectively
Consistent with P-wave cs states but other interpretations not ruled out
If cs, observed decays
DsJ*(2317)+  Ds+ p0
DsJ (2460)+  Ds*+ p0
are isospin violating  narrow
DsJ (2460)+  Ds+ g
also observed (and used here
to determine J)
DsJ (2573)+
Ds1(2536)+
Ds1(2460)
Ds0(2317)
Ds*+
Ds+
Godfrey-Isgur model
S-wave
P-wave
Stefania Ricciardi, BaBar
ICHEP04

19. Stefania Ricciardi, BaBar
B  DsJ (*)+ D(*)
hep-ex/
Data sample: 122 million B pairs
mES
m(DsJ)
Signal:
88 ± 17 events
DsJ*(2317)+
 Dsp0
Full reconstruction
of the exclusive
B decay
Sum over all
D(*)(0) modes
DsJ(2460)+
 Ds*p0
112 ± 14 events
We measure:
DsJ(2460)+
 Dsg
139 ± 17events
Stefania Ricciardi, BaBar
ICHEP04

20. Stefania Ricciardi, BaBar
B  DsJ (*)+D* Results
First measurement of all these modes
m(Ds+p0)
m(Ds*+p0)
m(Dsg )
B.F. (10-3)
DsJ*(2317)+  Dsp0
DsJ(2460)+ Ds*p0
DsJ(2460)+ Dsg B0
1.5 ± 0.4 ± 0.2( )
5.5 ± 1.2 ± 1.0( )
2.3 ± 0.3 ± 0.3( ) B+
0.9 ± 0.6 ± 0.2( )
7.6 ± 1.7 ± 1.8( )
1.4 ± 0.4 ± 0.3( )
B.F. Products
for BDsJ(*)+D*
Stefania Ricciardi, BaBar
ICHEP04

21. Stefania Ricciardi, BaBar
B  DsJ (*)+D Results
m(Ds+p0)
m(Ds*+p0)
m(Dsg )
B.F. (10-3)
DsJ*(2317)+  Dsp0
DsJ(2460)+ Ds*p0
DsJ(2460)+ Dsg B0
1.8 ± 0.4 ± 0.3( )
2.8 ± 0.8 ± 0.5( )
0.8 ± 0.2 ± 0.1( ) B+
1.0 ± 0.3 ± 0.1( )
2.7 ± 0.7 ± 0.5( )
0.6 ± 0.2 ± 0.1( )
B.F. Products
for BDsJ(*)+D
in good agreement with Belle results
Stefania Ricciardi, BaBar
ICHEP04

22. Stefania Ricciardi, BaBar
BDsJ(2460)+D : Helicity
J=2
DsJ+ (2460) Ds g qh
J=1
Data points from m(Dsg) fits
corrected for detector acceptance
and efficiency
J=1 (c2=4.0/4) preferred to J=2 (c2=36.4/4)
confirms Belle measurement
Stefania Ricciardi, BaBar
ICHEP04

23. X(3872) from B-J/y K-p+p- m(J/yp+p-)
hep-ex/
117 million B pairs
Discovered by Belle(2003) in B decays
Confirmed by CDF,D0 and BaBar
as narrow state decaying to J/y p+ p-
Nature unknown (Charmonium,
DD* molecule, ccg hybrid?)
Most puzzling: D0D*0 threshold
m(J/yp+p-)
y(2S)
30.5 ± 5.8 signal events ,
after bkg (combinatorial and peaking) subtraction, in 20 MeV:
3.862 < mX <3.882 GeV
X(3872)
X(3872)
y(2S)
mX(3782)= ±1.4 MeV/c2
B(B-X(3872)K-) x B(X(3872)J/yp+p-) = (1.28 ± 0.41) x10-5
m(p+p-)
Accumulation near kinematic limit in m(p+p-)
which is ~m(r0) for X(3872). Isospin-breaking ? More data needed!
Stefania Ricciardi, BaBar
ICHEP04

24. Stefania Ricciardi, BaBar
Search for B X -(3872) K
Data sample:
213 million B pairs
m(J/yp-p0)
If observed decay is X(3872)J/yr0
 charged partner may exist X(3872) - J/yr-
Search for B0  X-K+, B-  X-K0s
(and charged conjugates) with X-  J/y p-p0
If X isovector, decay rate to X should be twice
that observed for neutral X [BaBar: (1.28 ± 0.41) x10-5] B0
X-?
Mode
B0  J/y p-p0K+
B- J/y p-p0K0s
n obs. 87 31
n bkg.
101.8 ± 10.2
27.6 ± 6.2
n signal
-14.8 ± 13.9
3.4 ± 8.3
90%CL
< 5.8 x 10-6
< 11 x 10-6
Consistent with peaking
background (estimated from
mX sidebands) B0
A likelihood ratio test excludes
isovector hypothesis (Probability <1/600)
mES for |m(X)-3872| < 12MeV
Stefania Ricciardi, BaBar
ICHEP04

25. Stefania Ricciardi, BaBar
Summary
New results on B decays to open and hidden charm from BaBar:
Powerful application of recoil method for first separate determination of nc- and nc0
Most precise measurement of B0  Ds*+ D*- and Ds branching fractions
Improved measurements of B0  D(*)-pp+, B0  D(*) 0pp
Improved results of many exclusive B decays to charmonium, including:
measurement of B+  cc1 K*+
stringent upper limits on B  cc2 K(*)
First observation of B DsJ(*)+D*
New insights on X(3872): isovector hypothesis excluded
B(Ds+ f p+) = (4.71 ± 0.47(stat) ± 0.35(syst))%
Stefania Ricciardi, BaBar
ICHEP04

26. Additional Slides

27. Stefania Ricciardi, BaBar
Ds+ f p+
Data sample
124 million B pairs
1 - Partial reconstruction:
Signal 7414 ± 345
Partial reconstruction result
independent of B(Ds+ fp+):   
B(B0 Ds*+D*-)=(1.85 ± 0.09(stat) ± 0.16(syst) )%
2 - Full reconstruction:
B (B0  Ds* D*-, Ds f p+) = (8.71  0.78(stat)) x10-4
From the ratio BaBar obtains:
Signal 212 ±19
B(Ds+ f p+) = (4.71 ± 0.47(stat) ±0.35(syst))%
B(Ds+ f p+) = (3.6 ± 0.9)% PDG2004 (CLEO)
Stefania Ricciardi, BaBar
ICHEP04

28. Stefania Ricciardi, BaBar
c Production
B(B- c X) = B(B- Lc- X) - B(B- Lc+ Lc- K)
CKM allowed processes 1
Anticorrelated Lc production
not many different ways 3 2
Stefania Ricciardi, BaBar
ICHEP04