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Hadronic Substructure & Dalitz Analyses at CLEO. Mats Selen, University of Illinois HEP 2005, July 22, Lisboa, Portugal. Outline. Why the interest in charm Dalitz Plot (DP) analyses? Results from CLEO D 0 → K + K - p 0 D 0 p + p - p 0 D 0 K s 0 0 - PowerPoint PPT Presentation
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M. Selen, HEP-05 1
Hadronic Hadronic Substructure Substructure
& Dalitz & Dalitz Analyses at Analyses at
CLEOCLEO
Mats Selen, University of IllinoisHEP 2005, July 22, Lisboa, Portugal
M. Selen, HEP-05 2
Outline Why the interest in charm Dalitz Plot (DP) analyses? Results from CLEO
D0 → K+K0 D0
D0 Ks0
What CLEO-c will do for CKM angle /3.
M. Selen, HEP-05 3
CLEO II.V (9/fb)
CLEO III (14/fb)
CLEO-c (281/pb)
New RICHNew Drift Chamber
New siliconNew Trigger & DAQ
Replace siliconwith a wire
vertex chamber
CLEO Evolution
M. Selen, HEP-05 4
Why bother? Need to understand the brown muck.
Final state interactions are tricky Relative amplitudes and phases hard to calculate –
must measure. Need to sort out the best way to model ≥ 3
body decays Isobar, K-matrix, … People have not always agreed on best approach
Important engineering measurement for getting the most out of b-factory data. For example, extracting 3 from BDK
M. Selen, HEP-05 5
The power of the DP approach Interference is a beautiful thing !
Phase sensitivity is a very important handle
Example:D0 K
M. Selen, HEP-05 6
a1 ei1 + a2+ a3 + a4
+ a5 + a6 + a7 + a8ei5
ei2 ei3 ei4
ei6 ei7
=
ei8
79% (770) 13% K*(892)0
7.5% non-res
16% K*(892) 4.1% K*(1430)0
3.3% K*(1430) 1.3% K*(1680) 5.7% (1700)
M. Selen, HEP-05 7
Relevance to 3
There are several schemes to access /3 by exploiting interference in the decays of charged B mesons to charm: B DK D K*K
Grossman, Ligeti, Soffer PRD 67 (2003) Suprun, Rosner PRD 68 (2003) CLEO analysis of D KK
D 3-body/Dalitz Giri, Grossman, Soffer, Zupan PRD 68 (2003) CLEO analysis of D KS,
M. Selen, HEP-05 8
Method for measuring CKM phase by looking at B± → (K*+ K)DK ± and B± → (K* K)DK ±
Needs a measurement of the strong phase difference D between D0 → K*+ K– and D0 → K*– K+.
Dalitz analysis of D0 → K+K0 will yield D
D0KK
=0 =180
M. Selen, HEP-05 9
K*
K*
m
2 (G
eV/c
2 )2
m2 (GeV/c2)2
Signal Fraction 77.4%
Signal Events 565565(in the signal region)
m (GeV/c2)
K 0
signal region(after selection criteria)
D*+ → + D0
K+ K– 0
→
→
D0KKCLEO III CLEO III (4S) Region: : 8.965/fb8.965/fb
M. Selen, HEP-05 10
Preliminary FitStatistical errors only
ResonanceResonance amplitude amplitude aa phase phase
KK**(892)(892)++ Fixed to 1 Fixed to 0
K*(892)K*(892)-- 0.4951 0.0530 331.48 10.35
(1020)(1020) 0.4911 0.0487 99.55 12.94
nonresonantnonresonant 5.6660 0.4035 225.40 6.67
Fit FractionsFit Fractions
ResonanceResonance Fit FractionFit Fraction
KK**(892)(892)++ 45.20% 2.97%
K*(892)K*(892)-- 11.01% 2.25%
(1020)(1020) 8.57% 1.56%
nonresonantnonresonant 35.91% 3.46%
100.69% 5.32%
D0KK
M. Selen, HEP-05 11
m2 (GeV/c2)2m
2 (GeV/c2)2
K*K*
Fit projections reveal a feature/problem…
dips are we missing some physics ??Exploring K- P-wave K-matrix approach
M. Selen, HEP-05 12
*0~ ubcsVVKDB
Access 3 via interference between B± D0K± and B± D0K±
*0 ~ cbusVVKDB
b c
u u
u
sb
su u
cu
KS, 0
K±
B±D
~
3 from 3-body final states
00 3~
DreDD i
003
~DreDD i
suppressedfavored
M. Selen, HEP-05 13
2 SK
mmWhere is the amplitude of the D0 matrix element atthe point on the Dalitz Plot, and
yxf , yx,
mmfremmfDAmp i ,,)
~( 3
Once has been determined (where we come in) then
D+ and D Dalitz plots can be fit to determine 3. yxf ,
Amplitude differences willbe sensitive to 3.
~ ~
D+
~D
~
m+ m+
mm
D KS+
BELLE253/fb
~
(From B± decays)
M. Selen, HEP-05 14
Useful for studying 3 in charged B decays.
Like D0KS(discussed later)
Good system for CP violation search. Some predictions as high as 0.1% (ref)
Compare to D+ Has large S-wave component (FOCUS ref)
D0
M. Selen, HEP-05 15
m2() (GeV2)
m2 (
) (G
eV2 )
S/(S+B) ~ 80% S ~ 1100
9.0/fb
m2() (GeV2)
0 1 2 3m2() (GeV2)
0 1 2 3m2() (GeV2)
0 1 2 3
D0
M. Selen, HEP-05 16
Amplitude Phase(o) Fit Fraction %
+ 1 (fixed) 0 (fixed) 76.5±1.8±2.5
0 0.56±0.02±0.03 10±3±2 23.9±1.8±2.1
0.65±0.03±0.02 176±3±2 32.3±2.1±1.3
NR 1.03±0.17±0.12 77±8±5 2.7±0.9±0.2
Amplitude Phase(o) Fit Fraction %
+ 1 (fixed) 0 (fixed) 78.0±2.1
0 0.56±0.02 9±3 24.4±1.9
0.66±0.03 176±3 33.9±2.3
(500) 0.22±0.06 355±24 0.08±0.08
< 0.21 @ 95% CL
< 6.4 @ 95% CL
Amplitude Phase(o) Fit Fraction %
+ 1 (fixed) 0 (fixed) 76.3±1.9±2.5
0 0.57±0.03±0.03 10±3±2 24.4±2.0±2.1
0.67±0.03±0.02 178±3±2 34.5±2.4±1.3
K-matrix 0.70±0.20±0.12 2±14±5 0.9±0.7±0.2
< 1.9 @ 95% CL
proj
0 1 2 3 GeV2
0 1 2 3 GeV2
0 1 2 3 GeV2
See Au, Morgan, Pennington PRD 35, 1633 (1987)
M. Selen, HEP-05 17
D0
Only contributions plus small non-resonant component are required to fit Dalitz plot.
Very small D0 S-wave fit fraction (<0.9%) compared to FOCUS (56%) for D+ D+ / D0 S-wave
ratio > 36@95%CL Tree level estimate =
Flavor tagged D0 and D0 Dalitz plots also fit separately to limit DP integrated CP asymmetry: ACP =
18232
05.001.0 09.007.0
M. Selen, HEP-05 18
• Lots of brown muck • Complement KSanalyses• Good place to search for low mass
• No 00 to get in the way!
m2() (GeV2)
0 1 2
K*(890) + K0(1430) + f0 + NR
m2() (GeV2)
0 1 2
D0 Ks0S/(S+B) ~ 70% S ~ 700
m2 (
) (G
eV2 )
m2(S)RS (GeV2)
K*(890) + K0(1430) + f0 + NR +
M. Selen, HEP-05 19
S/(S+B) ~ 70% S ~ 700
m2 (
) (G
eV2 )
m2(S)RS (GeV2)
CLEO-II.V & III(~15 fb-1)
CLEO-c data(165 pb-1)
S/(S+B) ~ 72% S ~ 1500
M. Selen, HEP-05 20
What CLEO-c will do for3
mmfremmfDAmp i ,,)
~( 3
The determination of is presently the limiting systematic yxf ,
Belle and BaBar have studied the dependence of on
the D decay model (analysis used D0 Ks)
Belle - Phys.Rev.D70:072003,2004 hep-ex/0406067
BaBar – ICHEP04 paper hep-ex/0408088
o111377 17
193
o10102670
D Decay Model
Systematic
Uncertainty
M. Selen, HEP-05 21
Fit Fraction (%) (stat err shown)
0.34 ± 0.13
65.7 ± 1.3
26.4 ± 0.9
0.72 ± 0.18
f 4.3 ± 0.5
f 0.27 ± 0.15
f 9.9 ± 1.1
7.3 ± 0.7
1.1 ± 0.2
2.2 ± 0.4
NR 0.9 ± 0.4
m2(S) (GeV2) 0 1 2 3
m2() (GeV2) 0 1 2 3
m2(S) (GeV2) 0 1 2 3
m2 (
) (G
eV2 )
m2(S)RS (GeV2)
S/(S+B) ~ 98% S ~ 5300
0
1
2
0 1 2 3
CLEO-II.V D0 Ks
Rather low statistics compared to…
M. Selen, HEP-05 22
BaBar data with“CLEO” model
not so good
2.27x108 BB pairs
BELLE fits look like BaBar
M. Selen, HEP-05 23
Fit with additionalresonances muchbetter.
This includes BW
1 and 2 with ~10% fit fractions.
Causes big systematicuncertainty !
M. Selen, HEP-05 24
mmiemmfmmf ,,,
CLEO-c can help Do simultaneous CP tagged and flavor tagged analysis of D0 Ks [only at ’’(3770)]
Suppose we write
We will extract as well as in a model independent way.
This is exactly what the 3 analyses need.
mmmm ,,cos mmf ,
M. Selen, HEP-05 25
Many other CLEO-c Dalitz plot analyses are in the works:
SS
S S S
etc…many others
M. Selen, HEP-05 26
Conclusions CLEO has done (and continues to do) groundbreaking
work on charm Dalitz analyses. SSS, Implementation of K-Matrix amplitudes in fits
CLEO-c will open a new window on the charm sector by exploiting quantum correlations: CP tagged Dalitz Plot analyses
3, mixing, CP violation, … Double correlated Dalitz analyses (i.e. DP vs DP)
Stay tuned