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Doubly charmed B decays
B D(*)D(*)K
( for ~140 fb-1 )
JOLANTA BRODZICKA
INSTITUTE OF NUCLEAR PHYSICS, KRAKOW
BGM Nov 21, 2003
Outline




b  c c s transition
“wrong-sign” D production
physics motivations
analysis method
preliminary results ( for ~140 fb-1 ) :
signals and BF’s
B+ D0D0K+
B0 D-D0K+
B+ D0D*0K+
B0 D*-D0 K+
B+ D0D*+K0s
B0 D*-D*0K+
D(*)K and

B+ D*-D*+K0s
(no BF yet)
D(*)0 D0 mass spectra
( search for X(3872)→ D*0D0 )
summary and conclusions
JOLANTA BRODZICKA
B  D(*) D(*) K
BGM Nov 21, 2003
Leading quark diagrams B  D(*)D(*)K decays
b  cW - c c s
+ dd (uu) pair creation
( I ) through external W emission amplitudes
B+  D(*)0 D(*)+ K0
B0  D(*)- D(*)0 K+
( II ) internal W emission amplitudes (color-suppressed)
B+  D(*)+ D(*)- K+
B0  D(*)0 D(*)0 K0
( III ) external +internal W emission amplitudes
B+  D(*)0 D(*)0 K+
B0  D(*)- D(*)+ K0
22 decay modes + c.c
JOLANTA BRODZICKA
B  D(*) D(*) K
BGM Nov 21, 2003
Physics motivations
 B  D(*)D(*)K : good place to explore spectroscopy:
X  DD
 cc-bar states above DD threshold scarcely known ((3770) (4040) …)
 molecular charmonia ( X(3872) ? ) , ccqq states, ccg hybrid states…
Y  D(*)K

cs:
from W vertex
L= 0 0- Ds(1970) 1- D*s(2112) well known
L= 1
jP = 1/2+ 0+ DsJ± (2317) 1+ DsJ± (2457) seen, do not decay to DK
( chiral doublet to Ds± Ds*± )
jP = 3/2+ 1+ Ds1± (2536) 2+ DsJ± (2573) not seen in B decays
( do chiral partners exist?)
 measurement of the BF’s and their ratios:

important for understanding of factorization, color suppression
and ‘charm deficit ’ in B decays
B0  D(*)+ D(*)- K0S to probe both sin21 and cos21
JOLANTA BRODZICKA
B  D(*) D(*) K
BGM Nov 21, 2003

Analysis details
accepted events with: R2< 0.3
tracks with : abs(IP_dz)< 5cm
abs(IP_dr)< 0.4cm
K± : P(K/) > 0.4 ± : P(/K) > 0.1 electron veto: el_id < 0.95
K0S : abs( M(+ -) - MKs ) < 15MeV
only good_K0s
0 : E > 50 MeV abs( M( ) -M0 ) < 15MeV
 D(*) reconstruction
D0  K, K3, K0, Ks, KK
D±  K, Ks, KK, KsK
BF ~ 28% of total
BF ~ 12% of total
abs(M(D)-M(DPDG) ) < 20MeV ( D0 K0 : -50MeV )
vertex fit (cl > 0.) and mass constraint fit applied, p(D) < 2GeV in (4S) system
D*±  D0 ± abs(M(D*±)-M(D)-m ) < 2.5MeV
PDG
D*0  D0 0
abs(M(D*0)-M(D)-mPDG) < 5MeV
vertex fit (cl > 0.) applied
 B reconstruction :
all (22 + c.c) physical combinations D(*)D(*)K
B vertex fit: with IP and B constraints
Mbc > 5.2 GeV
-0.40 < E < 0.35 GeV
JOLANTA BRODZICKA
B  D(*) D(*) K
BGM Nov 21, 2003
D(*) plots for ~11fb-1 sample after preselection
Multi-candidates events treatment
p(D) < 2GeV in (4S) system
> 1 candidates in the same B sub-mode
 several D(*) candidates per event
 D(*)D(*) comb. with different K`s
D, D* probabilities (LR):
LR
LR
LR_D ( MD )=
LR_D* ( MD* )=
S(MD)
S(MD) + B(MD)
MD
MD
S(MD*)
S(MD*)+ B(MD*)
S(MD), B(MD) and S(MD*), B( MD*)
parameterization from MD and MD* fits
to data ( “inclusively” reconstr. D(*) )
JOLANTA BRODZICKA
LR
LR
MD*
B  D(*) D(*) K
MD*
BGM Nov 21, 2003
Choice of the best B candidate
B probability ( LR_B )
LR_B = LR_D(*)
×
( for each B decay sub-mode separately )
LR_D(*)

best B candidate : with max LR_B

equal LR_B case ( B`s differ only in K ) :
larger K±_ID or better K0S mass candidate chosen
S/(S+B) choice method “combines” both criteria:
(M-MPDG)/ and S/B ratio
LR_B used also for background discrimination
JOLANTA BRODZICKA
B  D(*) D(*) K
BGM Nov 21, 2003
LR_B cut
B+  D0D0K+
N/7.5MeV
N/7.5MeV
S / sqrt (S + B )
Signal MC
N/7.5MeV
(good for background reduction
and S/B improvement)
LR_D0 * LR_D0 cut
Data
B+  D0D0K+
for Mbc>5.27GeV
no LR cut
LR > 0.04
LR > 0.1
Signal MC: B+  D0D0K+ ( for BF=1.5 * 10-3 )
Background:B+  D0D0K+ Mbc sideband
JOLANTA BRODZICKA
B  D(*) D(*) K
E
BGM Nov 21, 2003
B0 D-D0K+
&
a little bit more on method
N/7.5MeV
plot for Mbc >5.27 GeV
My fitting method:
2dim Mbc vs. E unbinned likelihood fit:
L_Sig(Mbc, E) = S•( G (Mbc) • G (E) )
+ S•( G (Mbc) • G (E) )
+ S2•( G (Mbc) • G (E) )2
2 lost
 lost
L_Bckg (Mbc, E) = B•ARG (Mbc) • POL_2 (E)
All parameters
L= L_Sig + L_Bckg
E
N/2MeV
LR > 0.01
plot for abs(E)<25MeV
are kept free.
Yields for 3 regions:
They are in
S = 127.6 ± 15.3
fully reconstr.
agreement with MC
S = 728.7 ± 53.1 partially reconstr.:
B0 D-D*0 K+ B+ D-D*+K+ B0 D*-D0K+
S2 = 972.8 ± 68.0 partially reconstr.:
B0 D*-D*0 K+ B+ D*-D*+ K+
For fully reconstr. signal:
S= 127.6 ± 15.3
Stat_signif.= 10.9
eff = ( 6.98 ± 0.14 ) *10-4
Mbc
JOLANTA BRODZICKA
BF = ( 1 .68 ± 0.20 ± 0.25 ) * 10-3
B  D(*) D(*) K
BGM Nov 21, 2003
LR > 0.04
plot for Mbc >5.27 GeV
N/2MeV
N/7.5MeV
B+  D0D0K+
plot for abs(E)<25MeV
S = 94.4 ± 13.0
Stat_signif.= 9.3
eff = ( 4.80 ± 0.14 ) *10-4
BF = ( 1 .30 ± 0.18 ± 0.21 ) * 10-3
E
LR > 0.01
plot for Mbc >5.265GeV
N/2MeV
N/7.5MeV
B+ D0D*0K+
Mbc
plot for abs(E)<45MeV
S = 49.4 ± 11.6
Stat_signif.= 7.0
eff
= ( 0.39 ± 0.03 ) *10-4
BF = ( 8.84 ± 1.56 ± 1.5) * 10-3
E
JOLANTA BRODZICKA
Mbc
B  D(*) D(*) K
BGM Nov 21, 2003
plot for Mbc>5.27GeV
LR > 0.05
N/2MeV
N/7.5MeV
B0  D*-D0 K+
plot for abs(E)<25MeV
S = 86.9 ± 10.6
Stat_signif.= 12.8
eff
= ( 1.91 ± 0.07 ) *10-4
BF = ( 2.99 ± 0.37 ± 0.53 ) * 10-3
Mbc
E
B0  D*-D*0K+
plot for Mbc>5.27GeV
LR > 0.0
plot for abs(E)<45MeV
S = 43.4 ± 10.1
Stat_signif.= 7.1
eff
= ( 0.34± 0.03) *10-4
BF = ( 8.44 ± 1.97 ± 1.33) * 10-3
E
JOLANTA BRODZICKA
Mbc
B  D(*) D(*) K
BGM Nov 21, 2003
LR > 0.005
plot for Mbc>5.27GeV
N/2MeV
N/7.5MeV
B+  D0D*+K0s
S = 40.2 ± 10.1
plot for abs(E)<25MeV
Stat_signif. = 7.5
eff
= ( 0.46 ± 0.06 ) *10-4
BF = ( 5.80 ± 1.46 ± 1.18) * 10-3
Mbc
E
B0  D*-D*+K0s
S = 248.4 ± 22.6
D0(-,0,γ)D*+K0s
(maybe can be useful for time
dependent analysis)
LR > 0.0
S = 17.
v. clean (no LR-cut used)
(good_K0S used, looser
selection should give more)
JOLANTA BRODZICKA
B  D(*) D(*) K
BGM Nov 21, 2003
BF summary
NS
∑ (eff*BFsec)
[10-4]
→ D 0 D 0 K+
94.4 ± 13.0
4.99
1.25 ± 0.17 ± 0.20
B0 → D- D0 K+
127.6 ± 15.3
6.98
1.68 ± 0.20 ± 0.25
B0 → D*- D0 K+
87.0 ± 10.6
1.91
2.99 ± 0.37 ± 0.53
B+ → D0 D*+ K0
40.2 ± 10.1
0.46
5.80 ± 1.46 ± 1.18
B0 → D*- D*0 K+
43.4 ± 10.1
0.34
8.44 ± 1.97 ± 1.33
B+ → D0 D*0 K+
49.4 ± 11.6
0.39
8.84 ± 1.56 ± 1.50
__
77.9 ± 13.7
( 49.4 ± 11.6)
0.39
5.10 ± 0.90 ± 0.75
__
B+
__
__
B+ → D*0 D0 K+
JOLANTA BRODZICKA
B  D(*) D(*) K
BF
[10-3]
BGM Nov 21, 2003
Look for resonant structure: e.g.Dalitz plot & projections for
B0 D-D0K+
for signal-box events:
M( D0D- )
abs(E) < 25 MeV Mbc > 5.27 GeV
M ( D0D- )
N / 10MeV
S + B / 50MeV
M( D0K+ )
M( D0K+ )
Mbc sideband normalized
to background in signal box
JOLANTA BRODZICKA
M ( D-K+ )
2dim Mbc vs. E fit
in M( D0K+ ) bins
(to filter out bckg
from Dalitz-plot
projection)
fitted S
(plotted above bckg)
M( D0K+ )
fitted B
( fitted S+B gives good description of data )
Sbins - Sglobal ~1 
B  D(*) D(*) K
BGM Nov 21, 2003
K+
0
PS corrected for
(3770)D0D0
contribution)
B
0
D-D0K+
DSJ(2573)
N = 30.2 ± 8.4
M = 2.723 ± 0.014 GeV

= 0.084 ± 0.029 GeV
N = 80.2 ± 11.7
M = 2.714 ± 0.008 GeV

= 0.080 GeV fixed
M( D0K+ ) - M( D0K+ )
“right”-”wrong” flavor comb
N = 30.2 ± 5.7
M = 2.728 ± 0.013 GeV

N = 8.1 ± 2.3
M = 2.573 GeV fixed
= 0.080 ± 0.020 GeV
= 0.015 GeV fixed
B+ D*0D0K+
N = 15.1 ± 5.1
M = 2.720 GeV fixed
S / 50MeV

S / 50MeV
DD
0
S / 50MeV
B+
S / 50MeV
D0K+ resonant structure

Peak @ ~2730
sth new!
= 0.080 GeV fixed
fitted functions:
BW +&Phase Space shape from 3body signal MC
with free normalization (to describe non-resonant
SIGNAL with subtracted bckg
JOLANTA BRODZICKA
M( D0K+ )
B  D(*) D(*) K
component)
BGM Nov 21, 2003
Supporting evidence in D*K ?
N = 3.8 ± 1.6
M = 2.536 GeV fixed
S / 25MeV
B D(*)D*0K+
DS1(2536) ?

= 0.005 GeV fixed (exp.resol)
N = 27.7 ± 8.0
M = 2.613 ± 0.008 GeV
Partially reconstructed:
B  D0D*0K+ +  lost

Fitted:G+BW+BW+&PS
= 0.039 ± 0.014 GeV
N = 50.7 ± 15.3
M = 2.743 ± 0.009 GeV

S / 50MeV
B+ D0D*+K0s
S / 50MeV
B  D(*)D*+K0s
B0 D*-D*0K+
S / 50MeV
B+ D0D*0K+
= 0.050 ± 0.026 GeV
S / 50MeV
M( D*0K+ )
Partially reconstructed:
B+ D0D*+K0s +  lost
SIGNAL with
subtracted bckg
PS for 3body MC
JOLANTA BRODZICKA
M( D*0K+ )
B  D(*) D(*) K
M(D*+K0s)
BGM Nov 21, 2003
Other results
Phase Space shape
from 3body signal MC
B+ D0D0K+
N / 50MeV
S / 25MeV
B+ D0D*0K+
M ( D0 D*0 )
M ( D0D0 )
confirmation of (3770)→D0D0
in B+ D0D0K+
N = 25.0 ± 5.8
M = 3.770 GeV fixed
 = 0.0253 GeV fixed
fitted functions:
BW +sqrt(1-thr/x)*POL_3
Search for X(3872)→D0D*0
(in 10MeV bin) :
2 evts observed, 1 evt expected bckg
90% UL by counting method (Feldman-Cousins)
BF(B+→K+X(3872))xBF(X(3872)→ D0D*0) < 2.37x10-4
BF(B+→K+ (3770))xBF((3770)→ D0D0) = ( 3.0 ± 0.7 ± 0.5 )x10-4
JOLANTA BRODZICKA
B  D(*) D(*) K
BGM Nov 21, 2003
Summary

I have shown preliminary results ( for ~140 fb-1 ) :
signals and BF’s for following channels:
B+ D0D0K+
B0 D-D0K+
B+ D0D*0K+
B0 D*-D0 K+
B+ D0D*+K0s
B0 D*-D*0K+
B+ D*-D*+K0s
(no BF yet)
I studied D(*)K and D(*)0 D0 mass spectra:
X D0 K+
@ ~2730 MeV and width ~80MeV observed (sth new !)
in B0 D-D0K+ B+ D0D0K+ B+ D0D*0K+
evidence >3 for DsJ(2573) D0 K+
90% UL
in B0 D-D0K+
BF(B+→K+X(3872))xBF(X(3872)→ D0D*0) < 2.37x10-4
(3770)→D0D0 in B+ D0D0K+ confirmed

JOLANTA BRODZICKA
B  D(*) D(*) K
BGM Nov 21, 2003
Backup slides
JOLANTA BRODZICKA
B  D(*) D(*) K
BGM Nov 21, 2003
BF systematic error decomposition per mode
[%]
D0 D0 K+ D- D0 K+ D*- D0 K+ D0 D*+ K0 D*- D*0 K+ D0 D*0 K+
track eff.
8.3
8.2
13.8
13.8
13.0
7.9
K-id
5.9
5.6
5.8
4.0
5.4
5.1
Pi-id
2.6
2.7
3.0
3.0
2.6
2.4
Pi0 eff.
0.6
0.5
0.9
1.6
2.1
4.8
K0s eff.
0.6
2.7
0.7
4.6
1.3
0.6
MCstat& BFsec
2.8
2.4
2.5
4.4
6.5
5.1
10.0
7.0
5.0
5.0
5.0
10.0
16.3
14.7
17.8
20.3
15.8
14.6
Fit

JOLANTA BRODZICKA
B  D(*) D(*) K
BGM Nov 21, 2003
BF comparison with other measurements
BF[10-3]
_
this analysis
(@140 fb-1)
Babar
(@75.9fb-1)
→ D0 D0 K+
1.25 ± 0.17 ± 0.20
1.9 ± 0.3 ± 0.3
B0 → D- D0 K+
1.68 ± 0.20 ± 0.25
1.7 ± 0.3 ± 0.3
B0 → D*- D0 K+
2.99 ± 0.37 ± 0.53
3.1 ± 0.4 ± 0.4
B+
_
5.80 ± 1.46 ± 1.18
5.2 ± 1.0 ± 0.7
B0 → D*- D*0 K+
8.44 ± 1.97 ± 1.33
11.8 ± 1.0 ± 1.7
B+ → D0 D*0 K+
_
B+ → D*0 D0 K+
+ E.Heenan(78.1fb-1) 1.66 ± 0.33 ± 0.35
+ Cleo (3fb-1)
B+ → D0 D*+ K0
_
+ R.Chistov(88 fb-1) 1.19 ± 0.24 ± 0.18
+ E.Heenan(78.1fb-1) 8.77 ± 0.80 ± 1.88
+ Cleo (3fb-1)
8.84 ± 1.56 ± 1.50
4.7 ± 0.7 ± 0.7
5.10 ± 0.90 ± 0.75
1.8 ± 0.7 ± 0.4
JOLANTA BRODZICKA
4.5 ± 2.3 ± 0.8
B  D(*) D(*) K
13.0 ± 5.4 ± 2.7
BGM Nov 21, 2003
s
e
t
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e
7
c
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.
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8
7
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.
2
0
.
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4
7
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.
2
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.
%
6
7
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.
3
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.
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8
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5
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.
%
8
7
%
.
5
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.
%
4
7
%
.
5
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.
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4
%
BF systematic error contributions
Tracking eff
/ ch.track
Slow_pi+ tracking eff.
K_id eff.
/kaon
pi_id eff.
/pi
pi0 eff.
/pi0
K0s eff.
/K0s
MC stat+BF_sec
N(BB)
Fit variants
Decay model
1.5%
5.0%
2.0%
1.0%
3.0%
4.5%
2-6%
0.5%
5-10%
7%
- negligible contributions from selection cuts (wide mass window cuts, no vtx cuts)
JOLANTA BRODZICKA
B  D(*) D(*) K
BGM Nov 21, 2003
Mbc & E “movie”
from 2dim Mbc vs. E fit
2.35 < M( D0K+ ) < 2.55 GeV
JOLANTA BRODZICKA
in M( D0K+ ) 50MeV bins for B0 D-D0K+ signal
2.55 < M( D0K+ ) < 2.75 GeV
B  D(*) D(*) K
2.75 < M( D0K+ ) < 2.95 GeV
BGM Nov 21, 2003
Mbc & E “movie”
from 2dim Mbc vs. E fit
in M( D0K+ ) 50MeV bins for B0 D-D0K+ signal
2.95 < M( D0K+ ) < 3.15 GeV
JOLANTA BRODZICKA
3.15 < M( D0K+ ) < 3.35 GeV
B  D(*) D(*) K
BGM Nov 21, 2003