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An Introduction to CLEO-c

An Introduction to CLEO-c. THE CLEO COLLABORATION Albany • CalTech • Carnegie Mellon Cornell • Florida • Harvard Illinois • Kansas • Minnesota Oklahoma • Ohio State • Pittsburgh Purdue • Rochester • SMU Syracuse • UC San Diego • Vanderbilt Wayne State +. Motivation.

macaulay-velazquez
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An Introduction to CLEO-c

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  1. An Introduction to CLEO-c THE CLEO COLLABORATION Albany • CalTech • Carnegie Mellon Cornell • Florida • Harvard Illinois • Kansas • Minnesota Oklahoma • Ohio State • Pittsburgh Purdue • Rochester • SMU Syracuse • UC San Diego • Vanderbilt Wayne State + ...

  2. Motivation • Fundamental flavor physics in charm sector • Precise methods for strongly interacting theories need development, verification • Nonperturbative QCD limits flavor physics • Physics beyond Standard Model will have nonperturbative sectors. • Physics beyond the Standard Model may appear in unexpected places. CLEO-c: precise measurements of semileptonic, leptonic rates, absolute branching fractions … CLEO-c: precise measurements of form factors, decay constants, quarkonia spectroscopy and decay, … CLEO-c: D-mixing, charm CP, rare decays of charm and tau.

  3. Lattice QCD -- finally? • Only complete definition of QCD • perturbative and nonperturbative • 1989: Ken Wilson declares dead • Last 5 years: renaissance • improvements in algorithms drive progress • perturbation theory “fixed” • NRQCD,HQET for heavy quarks • improved discretizations (large lattice spacings) • Cornell workshop (Jan. 2001): • ~1% accuracies possible within 2-3 years with current techniques • B,D systems •  and  • Light systems • New data  new techniques • Eg. Glueballs: handle unstable states

  4. Precision CKM constraints? • How would CKM magnitude constraints differ w/ few percent uncertainties? • Crucial caveats: • Need precision theory (lattice < 10 yrs) • Need precision checks of theory (CLEO-c) • Need roadmap to translate precision on <P|Jm|0> (fP) to that on <P0|H|P0> (BPfP)

  5. Precision CKM constraints? • How would CKM magnitude constraints appear w/ few percent uncertainties? • Crucial caveats: • Need precision theory (lattice < 10 yrs) • Need precision checks of theory (CLEO-c) • Need roadmap to translate precision on <P|Jm|0> (fP) to that on <P0|H|P0> (BPfP) Current uncertainties

  6. Precision CKM constraints? • How would CKM magnitude constraints appear w/ few percent uncertainties? • Crucial caveats: • Need precision theory (lattice < 10 yrs) • Need precision checks of theory (CLEO-c) • Need roadmap to translate precision on <P|Jm|0> (fP) to that on <P0|H|P0> (BPfP) Few % uncertainties

  7. The CLEO-c Program 2 0 0 2 Prologue: Upsilons ~1-2 fb-1 ea. Y(1S) ,Y(2S), Y(3S)… Spectroscopy, Matrix Elements, Gee 10-20 times existing world’s data In the works 2 0 0 3 Act I: y(3770) -- 3 fb-1 30M events, 6M tagged D decays (310 times MARK III) 2 0 0 4 Act II: √s ~ 4100 -- 3 fb-1 1.5M DsDs, 0.3M tagged Ds decays (480 times MARK III, 130 times BES II ) 2 0 0 5 Act III: y(3100) -- 1 fb-1 1 Billion J/y decays (170 times MARK III 20 times BES II)

  8. The CLEO III Detector 93% of 4p sp/p = 0.35% @1GeV dE/dx: 5.7% p @minI 83% of 4p 87% Kaon ID with 0.2% p fake @0.9GeV 1.5 T now,... 1.0T later 93% of 4p sE/E = 2% @1GeV = 4% @100MeV Trigger: Tracks & Showers Pipelined Latency = 2.5ms Data Acquisition: Event size = 25kB Thruput < 6MB/s 85% of 4p For p>1 GeV

  9. CESR: s ~ 2–5 GeV? • Low E task force (Apr. 2000) • CLEO solenoid 1.5T  1T • Long damping time () problematic •  add wigglers to decrease  • Wiggler’s now being prototyped • 2T over 5 cm beam aperture •  superconducting only option • Normal Cu/Fe: 300 kW power/unit (4MW!) • Permanent: 1.2T maximum • Final configuration: 14 modules • Short, modular, identical • Same technology needed for NLC damping rings • $5M for CESR reconfiguration

  10. CESR projections • Expected machine performance: • Best estimate: 3x1032 cm-2 s-1@ 1.885 GeV • Wiggler-dominated radiation: L ~ E2 • Ebeam/Ebeam ~ 8x10-4 at J/ • yield estimations: Conservative L ~ E3 • (4S): Ldt = 70 pb-1/day  50 pb-1/day • (beam width folded into effective) • 5 days/wk • 7 months / yr • Synchrotron radiation source needs 10 GeV

  11. Anticipated schedule • July ‘01: install superconducting quads • Low E machine studies + 10 GeV physics can coexist • Nov ‘01: (nS) running • ~Oct ‘02: CLEO-c/CESR reconfig. • silicon  drift chamber replacement • additional RF cavities • wiggler installation • Spring ‘03: charm running • Weak physics: (3770), DSDS (~4.1 GeV) • QCD: J/  • 3-4 year program for charm running • Main 3 yr program plus: •  threshold (m), cc threshold (pK), ’, R “spot checks”, (nS) w/ n>4

  12. EW highlights • D(S)/, D(S)Xl • Precision fD, fDs, BSL, form factors • Precision Vcd, Vcs (7%,16%  ~1.5%) • Confront QCD theory predictions •  • Vub, Vcb, hopefully  FBBB, FKBK, … • Absolute branching fractions (1-2%) • B rates “normalized” to D branching frac’s • D0K-p+, D+K-p+pimproved Vcb • Factorization • Future Rb, Rc • Mixing/CP: coherent D0D0 at (3770) • correlations  unique opportunities C=-1 L= 1

  13. QCD Probes • Verify tools for strongly–coupled theories • Quantify accuracy for extracting EW physics • Glueball (gg) spectra (lack thereof?!) • Gauge particles as constituents! • Also: hybrids ( ) • bb/cc resonances • Mass spectra  •  • Radiative transitions  ¯ confinement relativistic corr.’s wave fcn. technology: Form factor tech.

  14. c ¯ c      X G M Glueball search: 3-prong strategy • J/ • CLEO-c: 109 J/  ~6 x 107 J/ X • Copious color singlet gg: JPC=0++,0-+,2++ • Partial Wave analysis: • JP’s of contributing resonances • Absolute BF’s: pp,KK,pp,,… • Handle #1 on gluonic content • e+e-  e+e-  e+e-X • CLEO-c: 25 fb-1 good gg data already handles

  15. G M • (1S)X (1S) vs J/ : Rate suppressed ~4000 in 1.5 GeV range No PWA, BF’s glueball vs mesonic content? Farrar, Close, Li

  16. Inclusive help: •  spectrum from J/ X: • 10-4 sensitivity for narrow resonance • Eg: ~25% efficient for fJ(2220) • Suppress hadronic bkg: J/X

  17. fJ(2220): Glueball candidate • Now you see it… BES (1996) MKIII (1986)

  18. ?? LEAR 1998 L3 1997 2 3 • Now you don’t… • Crystal barrel: • pp • … or do you? • … or don’t you? OPAL 1998 L3 Signal Jetset collaboration: A new signal in  rumored (2001) 2 3 MKK

  19. fJ(2220): CLEO-c reach • fJ2220 • CLEO II: B fJ /KSKS < 2.5(1.3) eV • CLEO III: sub-eV sensitivity • Compare f2’ (ss): BKK ~ 90 eV • (1S): Tens of events

  20. Scalar (0++) glueball • 0++: 3 broad states • f0(1370) • f0(1500) • fJ(1710) • qq and gg mix • Supernumerary states? Morningstar, Peardon CLEO-c: Confirm JP Establish JP • Can measure many branching fractions… • needed for gluonic vs mesonic content

  21.  resonances • Heavy hybrids (qqg) • Expect ~1 GeV heavier than qq counterpart • Search using (1S)(ccg) + X • Find it: scan e+e- at ccg resonance • bbg: “guided” scan? •  studies: good lattice teeth-cutting • Establish: 75 evt’s • Discover/probe b(’), hb • 13000 (1S)b • ~60 (2S)b • (3S): b’, hb • Scans:ee to few % • (n+1S)(nS) • ee/ • Bll < 1%

  22. CLEO-c program: summary • Powerful physics case • Precision flavor physics - at last! • Nonperturbative QCD - at last! • Probe for New Physics • Unique: not duplicated elsewhere • High performance detector • Flexible, high-luminosity accelerator • Experienced collaboration • New collaborators welcome/encouraged! • Optimal timing • Flavor physics of this decade • Beyond the SM in next decade • Resonance with LQCD...

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