1 M. Selen, DOE Visit, 2004 UIUC – HEP: CLEO Task Mats Selen Aug 5, 2004 m 2 ( ) (GeV 2 ) m 2...
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Transcript of 1 M. Selen, DOE Visit, 2004 UIUC – HEP: CLEO Task Mats Selen Aug 5, 2004 m 2 ( ) (GeV 2 ) m 2...
M. Selen, DOE Visit, 2004 1
UIUC – HEP: UIUC – HEP: CLEO TaskCLEO Task
Mats Selen Aug 5, 2004
m2() (GeV2)
m2 (
)
(GeV
2 )
M. Selen, DOE Visit, 2004 2
Involvement in CLEO-c:• CLEO Spokesman : Mats (with David Cassel)• CLEO Run Manager : Topher• Trigger Hardware : Topher, Norm, Paras• Physics (of course) : Everyone
Analyses: DS (BR, double partial recon) : Jeremy (GG - finished) D0Ke (Mixing Analysis) : Chris (MS - finishing) D0KS00 (BR & Dalitz Analysis) : Norm, Bob, Topher, Mats D0K+K0 (BR & Dalitz Analysis) : Paras, Bob (MS) D0+0 (Dalitz Analysis) : Charles (MS – finished*)
New UIUC Involvement: Jim Wiss & Doris Kim• Expertise in Dalitz analyses and SL decays• Already involved with several analysis• Very interested in D Ke (more later)
M. Selen, DOE Visit, 2004 3
TRCR
Mixer/ShaperBoards
TILE(8)
ASUM
QVME
TILE (16)
ASUM
AXTR(16) AXX(16)
DR3 - TQT
STTR(12)
TRCR
L1D
G / CAL
DFC
CLEO
An
alo
g
Gates
ctrl
.
Mixer/Shaper Crates (24)
QVME
TPRO(2)
TCTL
TIM
DM/CTL
TIM
DM/CTL
TIM
DM/CTL
TPRO(4) TIM
DM/CTL
TIM
DM/CTL
AXPR
CCGL
SURF
SURF
Drift Chamber Crates
Axi
al t
rack
erS
tere
o t
rack
er
Bar
rel C
CE
nd
cap
CC
CC
Dig
ital
Lev
el 1
dec
isio
nF
low
co
ntr
ol &
Gat
ing
DAQ
The CLEO-c Trigger
M. Selen, DOE Visit, 2004 4
What it Looks Like (all more or less alike to untrained eye)
M. Selen, DOE Visit, 2004 5
DS (Jeremy Williams, GG)
CLEO-II.V
• Badly measured at present: World average B(DS ) = (3.6 ± 0.9)%• Calibrates other DS decays: Equivalent of D0K+ for D0 decays.
Some DSome DSS branching fractions branching fractions Some DSome D00 branching fractions branching fractions
M. Selen, DOE Visit, 2004 6
Look for B0 DS*+ D*
Double Partial Reconstruction Approach:
N(DS)
N(DS)Need to evaluate
Using the fact that N(D*S) = N(D*) from B DS
* D* to relate (1) and (2) and find B(DS)
DS s D0
DS s (K…) Use to find N(D*S) from B DS* D*
(1)
DS s D0
Use to find N(D*) from B DS* D*(…) s D0(2)
M. Selen, DOE Visit, 2004 7
SignalBackgroundTotal
M. Selen, DOE Visit, 2004 8
Preliminary new CLEO results:B(DS ) = (2.45 ± 0.42 ± 0.19)%
M. Selen, DOE Visit, 2004 9
D0 Ke (Mixing)
Chris Sedlack & MS
CLEO-II.V
Right Sign Signal (RS)D*+ + D0; D0 Ke+
D*+ + D0; D0 D0; ; D0 Ke Wrong Sign Signal (WS)
Some other + ; D0 Ke Example of Wrong Sign Background
Hard part: Telling WS signal from backgroundHard part: Telling WS signal from backgroundChris’ solution: Neural Net looking at a variety of kinematic vars.Chris’ solution: Neural Net looking at a variety of kinematic vars.
M. Selen, DOE Visit, 2004 10
Training & Training & Evaluating Evaluating the Nets:the Nets:
WS SignalWS Signal WS BackgroundWS Background
r r
M. Selen, DOE Visit, 2004 11
Fit for mixed & unmixed yields Fit for mixed & unmixed yields using proper lifetime distribution:using proper lifetime distribution:
Get signal and background shapes from MC. Get signal and background shapes from MC.
Example fit of partial data sampleExample fit of partial data sample
RMIX = 1.1 ± 0.76 %
Studying cuts & systematics beforeStudying cuts & systematics beforeopening the box on rest of dataopening the box on rest of data
M. Selen, DOE Visit, 2004 12
D0 Ks0 Dalitz(Norm, BIE & MS)
CLEO-II.V+III
• Complement KSanalyses• Good place to search for low mass
• No 00 to get in the way!• Norm re-writing code• Switching to CLEO-c data
S/(S+B) ~ 70% S ~ 700
m2 (
)
(GeV
2 )
m2(S)RS (GeV2)
m2() (GeV2)
0 1 2
K*(890) + K0(1430) + f0 + NR
m2() (GeV2)
0 1 2
K*(890) + K0(1430) + f0 + NR +
Lots more workto do !
M. Selen, DOE Visit, 2004 13
D0KK+0 Dalitz(Paras Naik, BIE & MS)
CLEO-III New method for measuring CKM phase by looking at B–
→ D0 K–, where D0 → K* K. Phys.Rev. D67 (2003) 071301, Grossman, Ligeti, & Soffer Needs a measurement of the strong phase difference D between D0 →
K*+ K– and D0 → K*– K+. D0 → K+ – 0 is a great place to measure D via interference!
– Phys.Rev. D68 (2003) 054010, Rosner & Suprun
Dalitz analysis - Resonant substructure Previous D0 → K+ K– 0 branching ratio measurement
(CLEO II) can be revisited.
Vcd Vcb*
Vud Vub* Vtd Vtb
*
CLEO II result / PDG Value, 151 ± 42 events, 2.7 fb-1
Phys.Rev. D54 (1996) 4211, Asner, et al.
B(D0 K+ K– 0) = (0.14 0.04)%
M. Selen, DOE Visit, 2004 14
Signal Fraction 77.4%
Signal Events 565565(in the signal region)
m (GeV/c2)
Both D0’s and D0’s plotted
“K+” is really K for a D0, etc…
Data and Dalitz PlotData and Dalitz Plot
K*
K*
m
2
(GeV
/c2 )
2
m2 (GeV/c2)2
CLEO III CLEO III (4S) Region: : 8.965/fb8.965/fb
726 points
K 0
signal region(after selection criteria)
Dominant resonances:
K* (892 MeV/c2) (1019 MeV/c2)D*+ → + D0
K+ K– 0
→
→
DATA
DATA
M. Selen, DOE Visit, 2004 15
Dal
itz
Fit
Pro
ject
ion
sD
alit
z F
it P
roje
ctio
ns
K*m2 (GeV/c2)2
DATA
K*
m2 (GeV/c2)2
m2 (GeV/c2)2
M. Selen, DOE Visit, 2004 16
Dalitz Plot FitDalitz Plot Fit
Preliminary!!!Errors only from fit statistics
ResonanceResonance amplitude amplitude aa phase phase KK**(892)(892)++ Fixed to 1 Fixed to 0
K*(892)K*(892)-- 0.5220 0.0541 331.28 10.10
(1020)(1020) 0.6157 0.0573 102.80 13.27
nonresonantnonresonant 5.8390 0.4506 223.10 7.88
CLEO IIICLEO III
Just when things were humming along… - disk crash - still recovering, taking opportunity to rewrite much of analysis code (i.e. make it better etc).
M. Selen, DOE Visit, 2004 17
D0+0
(Charles Plager)
CLEO-II.V
m2() (GeV2)
m2 (
)
(GeV
2 ) S/(S+B) ~ 80%
S ~ 1100
No contribution from (500) at ~1% level
m2() (GeV2)
0 1 2 3m2() (GeV2)
0 1 2 3m2() (GeV2)
0 1 2 3
Amplitude Phase Fit Fraction
+ 1 (fixed) 0 (fixed) 76.5±1.8±4.8
0 0.56±0.02±0.07 10±3±3 23.9±1.8±4.6
0.65±0.03±0.04 4±3±4 32.3±2.1±2.2
NR 1.03±0.17±0.31 77±8±11 2.7±0.9±1.7
** PRD in the works **** PRD in the works **
M. Selen, DOE Visit, 2004 18
The Future of Charm Physics: CLEO-c
(3770) – 3 fb-1
30 million DD events, 6 million tagged D decays(310 times MARK III)
MeV – 3 fb-1
1.5 million DsDs events, 0.3 million tagged Ds decays(480 times MARK III, 130 times BES)
(3100), 1 fb-1 & (3686) ~1 Billion J/ decays(170 times MARK III, 20 times BES II)
4140~S
Underway !
CLEO-c
M. Selen, DOE Visit, 2004 19
CLEO-c What’s new ?
M. Selen, DOE Visit, 2004 20
The Future of Charm Physics: CLEO-c
Heavy Flavor Physics: “overcome QCD roadblock”
Leptonic decays decay constants
Semileptonic decays Vcd, Vcs, V_CKM unitarity check, form factors
Absolute D Br’s normalize B physics
Test QCD techniques in c sector, apply to b sector improved Vub, Vcb, Vtd, Vts
Physics beyond SM: where is it?
• CLEO-c: D-mixing, charm CPV, charm/tau rare decays.
• CLEO-c: precision charm absolute Br measurements
• CLEO-c: precise measurements of quarkonia spectroscopy &decay provide essential data to calibrate theory.
Physics beyond SM will have nonperturbative sectors
M. Selen, DOE Visit, 2004 21
CLEO-c will soon have 50x more data than this!
M. Selen, DOE Visit, 2004 22
Single & Double Tagging:
e+ e
0D
0D
+
K+
M. Selen, DOE Visit, 2004 23
Absolute D branching ratios (S & D tagging)
M. Selen, DOE Visit, 2004 24
Absolute D branching ratios (S & D tagging)
M. Selen, DOE Visit, 2004 25
De
Tagging cleans things SL decays up a lot:
M. Selen, DOE Visit, 2004 26
SL branching fractions with CLEO-c now (57.2 pb-1)
27
A first analysis for Doris & Jim
0. The lack of final state interactions makes semileptonic decay a particularly clean environment for studying hadronic physics. An example is the complicated physics of broad s-wave resonances.
1. FOCUS was able to observe s-wave interference with the dominant K*(896) channel in D+K and determine the phase shift near the K* pole but FOCUS did not attempt to measure the variation of s-wave phase with K mass because of backgrounds.
2. How well can Cleo-c follow the s-wave phase and amplitude variation given a yield comparable to FOCUS but with greatly reduced backgrounds?
3. What can we learn about interference in other 4 body semileptonic decay?
Studying hadronic physics in charm semileptonic decay
M. Selen, DOE Visit, 2004 28
Interference in D+ K* DataMC
K* interferes with S- wave K and creates a forward-backward asymmetry in the K* decay angle with a mass variation due to the varying BW phase
F-B
asy
mm
etry
(m K
The S-wave amplitude is about 7% of the (H0) K* BW with a 45o relative phase
Focus “K*” signal
The same relative phase as LASS
matches model
-15% F-B asymmetry!
M. Selen, DOE Visit, 2004 29
Learning more about the s-wave amplitudes
const ampLASS amp
25 MeV bins
M(K)
Re
Im
BW
The higher K mass is where the amplitude variation is most interesting. As the s-wave phase shift passes 900 , the cosV asymmetry should reverse. We need the background free environment of CLEO-c to see this
even
ts
Cos
V
const ampLASS amp
Focus was limited to the K* peak region because serious non-charm backgrounds dominate out of this region. There is almost no discrimination between a constant and the expected s-wave amplitude from scattering experiments in the narrow region probed by Focus.
M. Selen, DOE Visit, 2004 30
Related SL physics1. Does s-wave interference occur in decays such as De
The FOCUS environment has far too much background to see this
2. What is the q2 dependence of form factors that describe the coupling to the s-wave piece? This might provide additional LQCD tests. The FOCUS q2 resolution is too poor to resolve this
3. For that matter-- what is the q2 dependence of the K* helicity amplitudes All experimentalists have been assuming the spectroscopic pole forms But we know the spectroscopic poles are wrong for DKe
A journey of 1000 miles begins with a single step….
Km
From 60 pb-1 CLEO-c
DataMC
Even a totally un-cut sample has a beautiful K* signal that is well simulated
Doris and Jim are starting to learn the ropes of doing a CLEO-c analysis
Doris is spending about half of her time at Cornell
M. Selen, DOE Visit, 2004 31
Involvement in CLEO-c:• CLEO Spokesman : Mats (with David Cassel)• CLEO Run Manager : Topher• Trigger Hardware : Topher, Norm, Paras• Physics : Everyone
Analyses: DS (BR, double partial recon) : Jeremy (GG - finished) D0Ke (Mixing Analysis) : Chris (MS - finishing) D0KS00 (BR & Dalitz Analysis) : Norm, Bob, Topher, Mats D0K+K0 (BR & Dalitz Analysis) : Paras, Bob (MS) D0+0 (Dalitz Analysis) : Charles (MS – finished*)
New UIUC Involvement: Jim Wiss & Doris Kim
Summary
Future looks great!