DPF May 2002 Ian Shipsey 1
CLEO-c & CESR-c: A New Frontier in Weak and Strong Interactions
Ian Shipsey,Purdue University
ψ′′→DoDo, Do→K-π+
K-
K+
π+
π−
The CLEO-c CollaborationCaltech, Carnegie Mellon,Cornell, Florida, Illinois,Kansas, Northwestern, Minnesota, Oklahoma, Pittsburgh, Purdue, Rochester, SMU, Syracuse,Texas PM,Vanderbilt, Wayne State
DPF May 2002 Ian Shipsey 2
• I am completely deaf • I communicate by lip
reading• BUT lip reading obeys
an inverse square law• Please write down your
questions• Pass them up to me• I will read out your
question before answering it
DPF May 2002 Ian Shipsey 3
CLEO-c : context
123310 −−× scmLpeak
ON OFFCESR/CLEO(*) 1.3 16.0 6.7 34 KEKB/Belle 7.2 76.8 (ON+OFF) ~140 PEPII/BABAR 4.6 87.5 (ON+OFF) ~165
610'# ×∫ sBLdt
SuperBaBarL =10 36
1010 BB/year
CLEOMajorcontributionsto B/c/τ physicsBut, no longercompetitive.Last Y(4S) runended June 25 ‘01
(*) CLEONo longerOperating at Y(4S)Belle/ BaBarON/OFFMay 17 02
BB/year
year
Thread#1
DPF May 2002 Ian Shipsey 4
Flavor Physics: is in “the sin2β era” akin to precision Z. Over constrain CKM matrix with precision measurements. Limiting factor: non-pert. QCD.
CLEO-c : the context
Charm at threshold can provide the data to calibrate QCD techniques → convert CESR/CLEO to a charm/QCD factoryCharm at threshold can provide the data to calibrate QCD techniques → convert CESR/CLEO to a charm/QCD factory
LHC may uncover strongly coupled sectors in thephysics that lies beyond the Standard Model
The LC will study them. Strongly-coupled field theories are an outstanding challenge to theoretical physics. Critical need for reliable theoretical techniques & detailed data to calibrate them.
This DecadeThread #2
The FutureThread #3
Example:The Lattice
Complete definition of pert & non. Pert.QCD. Maturedover last decade, can calculate to 1-5% B,D,Υ,Ψ…
“CLEO-c/CESR-C”
DPF May 2002 Ian Shipsey 5
CLEO-c Physics Program•flavor physics: overcome the non pert. QCD roadblock
• strong coupling in Physics beyond the Standard Model
•Physics beyond the Standard Model in unexpected places:
• CLEO-c: precision charm abs. branching ratio measurements
•CLEO-c: precise measurements of quarkonia spectroscopy &decay provide essential data to calibrate theory.
•CLEO-c: D-mixing, CPV, rare decays. + measure strong phasesCLEO-c will help build the tools to enable this decade’s flavor physics and the next decade’s new physics.
Abs D hadronicBr’s normalize B physics
Semileptonic decays: Vcs Vcd unitarity& form factors
Leptonic decays: decay constants
Tests QCD techniques in c sector, apply to b sector àImproved Vub, Vcb, Vtd & Vts
DPF May 2002 Ian Shipsey 6
δVub/Vub 25%lνB π
lνD π
δVcd/Vcd 7%lνD
Κ
δVcs/Vcs =11%l
B νD
δVcb/Vcb 5%
Bd Bd
δVtd/Vtd =36%
Bs Bs
δVts/Vts 39% δVtb/Vtb 29%
δVus/Vus =1%
ν
πΚ
lδVud/Vud 0.1%
eν
pn
tb
W
Goal for the decade: high precision measurements of Vub, Vcb, Vts, Vtd,Vcs, Vcd, & associated phases. Over-constrain the “Unitarity Triangles”- Inconsistencies → New physics !
Many experiments will contribute. CLEO-c will enable precise new measurementsat Bfactories /Tevtaron to be translated into greatly improved CKM precision.
Precision Flavor Physics
CKMMatrixCurrentStatus:
Wà cs
DPF May 2002 Ian Shipsey 7
Importance of measuring fD & fDs: Vtd & Vts
22
∝
∆∆
ts
td
BB
BB
s
d
V
V
fB
fB
MM
ss
dd
~5-7%
ηρ i−−1
1
ρηρ i+
η
2
3
2
1
108.820050.0
×
=∆ −
− tdBBd
VMeV
fBpsM dd
Lattice predicts fB/fD & fBs/fDs with small errorsif precision measurements of fD & fDs existed (they do not)We could obtain precision estimates of fB & fBsand hence precision determinations of Vtd and VtsSimilarly the ratio fD/fDs checks fB/fBs
d
d
BB
BB
d
d
Bf
Bf
MM )()(
5.0)( σσρρσ ⊕
∆∆
=
1.4% ~15% (LQCD)
DPF May 2002 Ian Shipsey 8
|f(q2)|2
|VCKM|2
I. Absolute magnitude & shape of form factors are a stringent test of theory. II. Absolute semileptonic rate gives direct measurements of Vcd and Vcs. III Key input to precise Vub vital CKM cross check of sin2β
b
c
u
d
HQETl ν
l ν
1) Measure D→π form factor in D→πlν. Calibrate LQCD uncertainties .2) Extract Vub at BaBar/Belle using calibrated LQCD calc. of B→π form factor.3) But: need absolute Br(D →πlν) and high quality dΓ (D →πlν)/dEπ neither exist
223K
2cs3
2F
2 |)(qf|p|V|24G
q +=Γ
πdd
π
π
B
D
Importance of absolute charmsemileptonic decay rates..
DPF May 2002 Ian Shipsey 9
310)8.10.24.19.46( −×±±±=cbV
The Importance of PrecisionCharm Absolute Branching Ratios I
Stat: 3.0% Sys 4.3% theory 3.8%Dominant Sys: επslow, form factors
& B(DàKπ) dB/B=1.3%
Vcb from zero recoil in B → D*l+νCLEO LP01
CLEO has single most precise Vcbby this technique (so far)
DPF May 2002 Ian Shipsey 10
( )( )
*+o
o +B
DB1
D
h
h
−
−
Γ →=
Γ →
Understanding charm content of B decay (nc)
Precision Z →bb and Z →cc (Rb & Rc)
At LHC/LC H → bb H → cc
The importance of precisionabsolute Charm BRs II
HQET spin symmetry test
Test factorization with B → DDs
DPF May 2002 Ian Shipsey 11
•CESR-c:•Modify for low energy operation:•add wigglers for transverse cooling (cost $4M)Expected machineperformance:
• ∆Ebeam ~ 1.2 MeV at J/ψ3.64.1 GeV
3.03.77 GeV
2.03.1 GeV
L (1032 cm-2 s-1)√s
CESRL(@Y(4S)= 1.3 x 1033
One day scan of the Ψ′:(1/29/02)
L ~ 1 x 1030
(~BES)Ψ′→J/ΨππJ/Ψ →µµ
DPF May 2002 Ian Shipsey 12
CLEO-c Proposed Run Plan
2002: Prologue: Upsilons ~1-2 fb-1 each at Y(1S),Y(2S),Y(3S),…Spectroscopy, matrix element, Γee, ηB hb
10-20 times the existing world’s data (started Nov 2001)
2003: ψ(3770) – 3 fb-1 (ψ(3770) →DD)30 million DD events, 6 million tagged D decays(310 times MARK III)
2004: MeV – 3 fb-1
1.5 million DsDs events, 0.3 million tagged Ds decays(480 times MARK III, 130 times BES)
2005: ψ(3100), 1 fb-1
–1 Billion J/ψ decays(170 times MARK III, 20 times BES II)
CLEOc
A 3 yearprogram
4140~S
DPF May 2002 Ian Shipsey 13
1.5 T now,... 1.0T later
93% of 4πσp/p = 0.35%
@1GeVdE/dx: 5.7% π @minI
93% of 4πσE/E = 2% @1GeV
= 4% @100MeV
83% of 4π87% Kaon ID with
0.2% π fake @0.9GeV
85% of 4πFor p>1 GeV
Trigger: Tracks & ShowersPipelinedLatency = 2.5µs
Data Acquisition:Event size = 25kBThruput < 6MB/s
CLEO III Detectorà CLEO-c Detector
DPF May 2002 Ian Shipsey 14
How well does CLEO III work?1st CLEO III were presented at LP01
3.18.186.182.29 8.26.2
0.35.44.31.4
1.74.6 ±+
−++−−
+−
Yield BR(B→Kπ)(x10-6)B→Kπ CLEOIII CLEO(1999)
Good agreement: between CLEOIII& CLEO II & with BaBar/BelleCLEO III works well
(Preliminary)B(B-→D0K-) = (3.8 ±1.3) x10-4 CLEOIII (2.9 ±0.8) x10-4 CLEO II
DPF May 2002 Ian Shipsey 15
Y(4S) event: ψ(3770) event:
ψ(3770) events: simpler than Y(4S) events
•The demands of doing physics in the 3-5 GeV range are easily met by the existing detector.
•BUT: B Factories : 400 fb-1 è ~500M cc by 2005, what is the advantage of running at threshold?
•Charm events produced at thresholdare extremely clean•Large σ, low multiplicity •Pure initial state: no fragmentation•Signal/Background is optimum at threshold
•Double tag events are pristine–These events are key to makingabsolute Br measurements
•Neutrino reconstruction is clean•Quantum coherence aids D mixing &CP violation studies
Do→K-π+ Do → K+e- ν
DPF May 2002 Ian Shipsey 16
Tagging Technique, Tag Purity
• ψ(3770) → DD √s ~4140 → DsDsCharm mesons have many large branching ratios (~1-15%) High reconstruction eff
→ high net tagging efficiency ~20% !
D → Kπ tag. S/B ~5000/1 ! Ds → φπ (φ→KK) tag. S/B ~100/1
Beam constrained mass
Anticipate 6M D tags 300K Ds tags:Anticipate 6M D tags 300K Ds tags:
MC MC
Logscale!
Logscale!
DPF May 2002 Ian Shipsey 17
~ Zero background in hadronic tag modes
Measure absoluteBr (Dà X) with double tagsBr = # of X/# of D tags
CLEO-c sets absolute scale for all heavy quark measurements
++−+
−
→
→
ππKD
tagD
MC
Decay √s L Double PDG CLEOcfb-1 tags (δB/B %) (δB/B %)
D0 →K-π+ 3770 3 53,000 2.4 0.6D+→ K- π+π+ 3770 3 60,000 7.2 0.7Ds →φπ 4140 3 6,000 25 1.9
Absolute Branching Ratios
DPF May 2002 Ian Shipsey 18
• Measure absolute Br (Ds → µν)
• Fully reconstruct one D (tag)
• Require one additional charged track and no additional photonsDs → µν
Vcs, (Vcd) known from unitarity to 0.1% (1.1%)
Ds → tag
2.3%UL33770D+ → µνf D+
1.6%33%34140Ds+ → τνf Ds
1.9%17%34140Ds+ → µνf Ds
CLEO-cPDGL fb-1Energy(MeV)Reaction
|fD|2
νl
|VCKM|2
•Compute MM2
•Peaks at zero for Ds+ → µ+ν
decay. Expect resolution of ~Mπo
MC
fDs from Absolute Br(Ds → µ+ν)
DPF May 2002 Ian Shipsey 19
Semileptonic Decays |VCKM|2 |f(q2)|2
U = Emiss - Pmiss
Assume 3 generation unitarity: for the first time measure complete set of charm PS → PS & PS → V absolute form factor magnitudes and slopes to a few% with ~zero bkgdin one experiment. Stringent test of theory!
TaggedEventsLowBkg!
D0 →πlν
D0 →Klν πdpdΓ
πp
CLEO-C
Lattice
πdpdΓ
πp
D0 →πlνD0 →πlν
DPF May 2002 Ian Shipsey 20
νφ→
ν→
ν→
νρ→
νπ→
ν→
ν→
νρ→
νπ→
ν→
ν→
+
+
+
++
++
++
++
+−
+−
+−
+−
eD:11
eKD:10
eKD:9
eD:8
eD:7
eKD:6
eKD:5
eD:4
eD:3
eKD:2
eKD:1
s
0*s
0s
0
0
_0*
_0
0
0
*0
0
0
10
2030
405060
70
8090
100
1 2 3 4 5 6 7 8 9 10 11
Decay modes
Err
or (
%)
CLEO-c Impact semileptonic dB/B
CLEO-c
PDG
CLEO-c will make significant improvements in the precision with which each absolute charm semileptonic branching ratio is known
DPF May 2002 Ian Shipsey 21
Determining Vcs and Vcd
If theory passes the test…..
combine semileptonic and leptonic decays to eliminate CKM
Γ(D+ →πlν) / Γ(D+ →lν) independent of VcdTest rate predictions at ~4%
Test amplitudes at 2%Stringent test of theory!
Γ(Ds→φlν) / Γ(Ds→lν) independent of VcsTest rate predictions at ~ 4.5%
Use CLEO-c validated lattice to calc B semileptonicform factor + B factory B→πlv for precise Vub
δVcs /Vcs = 1.6% (now: 11%)δVcd /Vcd = 1.7% (now: 7%)
υ+−→ eKD0
υπ +−→ eD0I
II
DPF May 2002 Ian Shipsey 22
Unitarity Constraints
|Vud|2 + |Vus|2 + |Vub|2 = 1 ??With current values this test fails at ~ 2.7σ (PDG2002)
|Vcd|2 + |Vcs|2 + |Vcb|2 = 1 ??CLEO –c: test to ~3% (if theory D →K/πlν good to few %)Also 1st column
)(
1)1(21
1
)(21
4
23
22
32
λ
ληρλ
λλλ
ηρλλλ
O
AiA
A
iA
VCKM +
−−−
−−
−−
=
1
=
=
b
sd
VVV
VVV
VVV
b
sd
tbtstd
cbcscd
ubusud
'
''
Compare ratio of long sides to 1.3%Also major contributions to Vub, Vcb, Vtd, Vts.
|VubVcb*||VudVcd*|
|VusVcs*|
DPF May 2002 Ian Shipsey 23
COMPARISON
0
5
10
15
20
25
30Er
ror
(%)
DfsDf
)KD(Br ππ→+
)D(BrS
φπ→
)KD(Br π→0
PDG
Compare B factories & CLEOCompare B factories & CLEO--CC
CLEO-c3 fb-1
Statistics limited
BFactory 400 fb-1
Systematics & Background limited
∆M=M(µνγ) −M(µν) GeV/c
CLEO: f DS : DS*→DS γ DS →µν
bkgd
S/N~14
B Factory CLEO technique with improvements
CLEO-c
%Error
DPF May 2002 Ian Shipsey 24
CLEO-c Probes of New Physics
D mix & DCPV suppressed in SM – all the more reason to measure themDD mixing x = ∆m/Γ y =∆Γ/2Γ ψ(3770)→DD(C = -1) exploit coherence, no DCSD. ψ(4140) →γDD (C = +1)√ rD=√[(x2+y2)/2] < 0.01 @ 95%CL (KπKπ, Klν,Klν)•CP violating asymmetries
• Sensitivity: Acp < 0.01• Unique:L=1,C=-1 CP tag one side, opposite side same CP
CP=±1 ← ψ(3770) → CP=±1 = CPV•CP eigenstate tag X flavor modeK+K- ← DCP← ψ(3770) → DCP → K-π+
Measures strong phase diff. CF/DCSD ∆cosδ ~0.05. Crucial input for B factories Needed for γ in B→DK
Gronau, Grossman,Rosner hep-ph/0103110
y’= ycosδ-xsinδx’= xcosδ+ysinδ
Rare charm decays. Sensitivity: 10-6
DPF May 2002 Ian Shipsey 25
• ψ and Υ Spectroscopy– Masses, spin fine structure
• Leptonic widths for S-states.– EM transition matrix elements
• Υ resonances winter ’01-summer’02 ~ 4 fb-1 total
• Uncover new forms of matter –gauge particles as constituents– Glueballs G=|gg ⟩ Hybrids H=|gqq ⟩
The current lack of strong evidence for these states is afundamental issue in QCD.Requires detailed understanding of ordinary
hadron spectrum in 1.5-2.5 GeV mass range.
Probing QCD
Study fundamentalstates of the theory
J/Ψ running 2005 109 J/ Ψ x 20 BES
Confinement,Relativistic corrections
Wave function Tech: fB,K √ BK f D{s)
Form factors
→Verify tools for strongly coupled theories→ Quantify accuracy for application to flavor physics
Rich calibration and testing groundfor theoretical techniques àapply to flavorphysics
DPF May 2002 Ian Shipsey 26
•Gluons carry color charge: should bind!
•CLEO-c 1st high statistics experiment with modern 4πdetector covering 1.5-2.5 GeV mass range. •Radiative ψ decays:ideal glue factory:
•(60 M J/Ψ→γX)
Gluonic Matter
Xγ
cc̄
•But, like Jim Morrison, glueballs have been sighted too many times without confirmation....
fJ(2220) →Κ+ Κ−
Example: fJ(2220) Inclusive γ Exclusive:
corroborating checks:Anti-search in γγ: /Search in ϒ(1S)
BES ’96 44CLEO-c 18K
Note: with more data BESII nolonger see evidence of fj(2220)
DPF May 2002 Ian Shipsey 27
• Crucial Validation of Lattice QCD: Lattice QCD will be able to calculate with accuracies of 1-2%. The CLEO-c decay constant and semileptonic data will provide a “golden,” & timely test. QCD & charmonium data provide additional benchmarks. (E2 Snowmass WG)
CLEO-c Physics Impact
Imagine a world Where we have theoreticalmastery of non-perturbative QCDat the 2% level
B Factories only ~2005
DPF May 2002 Ian Shipsey 28
• Crucial Validation of Lattice QCD: Lattice QCD will be able to calculate with accuracies of 1-2%. The CLEO-c decay constant and semileptonic data will provide a “golden,” & timely test. QCD & charmonium data provide additional benchmarks. (E2 Snowmass WG)
CLEO-c Physics Impact
Imagine a world Where we have theoreticalmastery of non-perturbative QCDat the 2% level
B Factories only ~2005
Theoryerrors = 2%
DPF May 2002 Ian Shipsey 29
The potential to observe new forms of matter- glueballs& hybrids, and new physics D mixing/CPV/rare Provides a discovery component to the program
• Knowledge of absolute charm branching fractions is now contributing significant errors to measurements involving b’s. CLEO-c can also resolve this problem in a timely fashion
• Improved Knowledge of CKM elements, which is now not very good.
CLEO-c Physics Impact
5%5%5%3%1.6%1.7%
39%36%25%5%11%7%VtsVtdVubVcbVcsVcd
B Factory/Tevartron
Data & CLEO-c
Lattice
Validation
(Snowmass E2 WG)
CLEO-cdata andLQCD
PDGPDG
Competition? Complimentary to Hall D/HESR/BEPCII-BESIII(All late decade none approved)
DPF May 2002 Ian Shipsey 30
The Road to Approval
•CLEO-C workshop (5/ 01): successful ~120 participants, 60 non CLEO•Snowmass working groups E2/P2/P5 : acclaimed CLEO-c• HEPAP LRPC “The sub-panel endorses CESR-c and recommends
that it be funded.”
CESR/CLEO Program Advisory Committee 9/01 endorsed CLEO-c•Proposal submission (part of Cornell 5-year renewal) to NSF 10/ 01.•External mail reviews uniformly excellent• NSF Site visit panel; 3/2002 endorsed CLEO-c• National Science Board will meet in August. • Expect approval shortly thereafter•See http://www.lns.cornell.edu/CLEO/CLEO-C/ for project description
•We welcome discussion and new members
DPF May 2002 Ian Shipsey 31
The CLEO-c Program: Summary
• Powerful physics case• Precision flavor physics – finally • Nonperturbative QCD – finally• Probe for New Physics
•Unique: not duplicated elsewhere• Highest performance detector to run @ charm threshold• Flexible, high-luminosity accelerator• Experienced collaboration
• Optimal timing• LQCD maturing• allows Flavor physics to reach•its full potential this decade• Beyond the SM in next decade
The most comprehensive& in depth study ofnon-perturbative QCD yetproposed in particle physics
Direct: Vcs Vcd &tests QCD techniquesaids BABAR/Belle/CDF/D0/BTeV/LHC-bwith Vub,Vcb,Vtd,Vts
DPF May 2002 Ian Shipsey 32
Backup Slides
DPF May 2002 Ian Shipsey 33
Analysis Tools
T
T
pp∆
TRKSIM
GEANT
−+→
→
KK
Ds
φ
φπ
•Our estimate of CLEO-C reach hasbeen evaluated using simulation tools developed during our long experience with heavy flavor physics
•Fast MC simulation: TRKSIM•Parameterized resolutions and efficiencies•Standard event generators•Excellent modeling of resolutions, efficiencies and combinatorial bkgd•No electronic noise or extra particles
•Performance validated with full GEANT simulation (CLEOG)
DPF May 2002 Ian Shipsey 34
Excess of µ over e fakes Background measured with electrons
CLEO signal 4.8fb-1
–Search for Ds* -> Ds γ, Ds -> µν–Directly detect γ, µ, Use hermeticity of detector to reconstruct ν –Plot mass difference but Backgrounds are LARGE!
•Use Ds -> eν for bkgd determination but precision limited by systematics
–FDs Error ~23% now (CLEO)–400 fb-1 ~6-9%
FDs at a B factory Scale from CLEO analysis
Compare to B factories, example f Ds
CLEO-c
∆M=M(µνγ) −M(µν) GeV/c
Ds → µν
DPF May 2002 Ian Shipsey 35
ISR Charm Events at B Factories
Initial State Radiation photon reduces √s
Measurement #events
BaBar/Belle CLEOc500 fb-1 3fb-1
Ds+ → µν 330 1,221
D+ → µν 50 672D+→ K- π+π+ 6,750 60,000Ds
+ →φπ 221 6,000
D
D
γ tag
γ
D tag
D study
ISR projectionsmade by BaBar showISR technique is notstatistically competitivewith CLEO-c.Systematic errors are also much larger.
DPF May 2002 Ian Shipsey 36
The fJ(2220) :A case study
Glueballs are hard to pin down, often small data sets & large bkgds
BES (1996)
MARKIII(1986) ?? LEAR
1998
pp→ Κ0sΚ0
sCrystal barrel:
New BES data does not
find the fJ(2220)!(but not published)
DPF May 2002 Ian Shipsey 37
fJ(2220) in CLEO-c?
Anti-search in Two Photon Data: γγ→fJ(2220):– CLEO II: ΓγγB( fJ (2220)→ππ/KSKS) < 2.5(1.3) eV– CLEO III: sub-eV sensitivity (new UL to appear ~1 week)– Upsilonium Data: ϒ(1S): Tens of events
5000–ηη850032pp530023KSKS
1860046K+K-
1300018π0π03200074π+π−CLEO-CBES
CLEO-c has corroborating checks:2
3
π+ π+ π0 π0
Κ+ Κ−
DPF May 2002 Ian Shipsey 38
Inclusive Spectrum J/ψ →γX
Inclusive photonspectrum a good place to search: monochromaticphotons for eachstate produced
Unique advantages of CLEO-c+ Huge data set+Modern 4π detector (Suppress hadronic bkg: J/ψ→π0X)+Extra data sets for corroboration γγ, ϒ(1S):Lead to Unambiguous determination of J PC & gluonic content
DPF May 2002 Ian Shipsey 39+ HESR at GSI Darmstadt p p complementary, being proposed: physics in 2007?
Quantity BES II CLEO-CJ/psi yield 50M > 1000MdE/dx res. 9% 4.9%K/pi separation up to 600 MeV 1500 MeVmomentum res. (500Mev) 1.3% 0.5%Photon resolution (100 Mev) 70 MeV 4 MeVPhoton resolution (1000 Mev) 220 MeV 21 MeVMinimum Photon Energy 80 MeV 30 MeVSolid angle for Tracking 80% 94%Solid angle for Photons 75% 95%
Comparison with Other ExptsChina:BES II is running now. BES II --> BES III upgradeBEPC I --> BEPC II upgrade, ~1032
2 ring design at 1033under consideration (workshop 10/01)Physics after 2006? if approval & construction goes ahead.
HALL-D at TJNAL (USA)γp to produce states with exotic Quantum NumbersFocus on light states with JPC = 0+-, 1+-, … Complementary to CLEO-C focus on heavy states with JPC=0++, 2++, …Physics in 2009?
being proposed
BES III complimentary to CLEO-c if new detector isComparable
DPF May 2002 Ian Shipsey 40
Additional topics
• Ψ’ spectroscopy (10 8 decays) η’chc….
• τ+τ− at threshold (0.25 fb-1)• measure mτ to ± 0.1 MeV• heavy lepton, exotics searches
• ΛcΛc at threshold (1 fb-1)• calibrate absolute BR(Λc→pKπ)
• R=σ(e+e- → hadrons)/σ(e+e- → µ+µ-)• spot checks
If timepermits
Likely tobe addedto runplan
DPF May 2002 Ian Shipsey 41
HEPAP Sub-panel on Long Range Planning for U.S.High-Energy Physics
•Appendix A: Roadmap for Particle Physics A.4.4 (pp 75-76.)"The CLEO collaboration has proposed a program using electron-positron annihilation in the 3 to 5 GEV energy region, optimized for physics studies of charmed particles. These studies would use the CESR storage ring, modified for running at lower energies, and the upgraded CLEO detector. The storage ring would offer significantly higher luminosity and the CLEO detector would provide much better performance than has been available to previous experiments in this energy region.”“The improved measurements of charmed particle properties and decays are matched to theoretical progress in calculating charm decay parameters using lattice QCD. The conversion of the storage ring for low energy runningwould cost about $5M, and could be completed in a year, so that physics studies could begin sometime in 2003. The physics program would then require three years of running the modified CESR facility
“The sub-panel endorses CESR-c and recommends that it be funded.”
•http://doe-hep.hep.net/home.html