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CLEO-c & CESR-c: A New Frontier in Weak and Strong Interactions

CLEO-c & CESR-c: A New Frontier in Weak and Strong Interactions. Ian Shipsey, Purdue University. The CLEO Collaboration Albany, Carnegie Mellon, Cornell, Florida, Illinois, Kansas. Minnesota, Ohio-State, Pittsburgh, Purdue, Rochester, SMU, Syracuse, Texas PM, Vanderbilt, Wayne State.

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CLEO-c & CESR-c: A New Frontier in Weak and Strong Interactions

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  1. CLEO-c & CESR-c: A New Frontier in Weak and Strong Interactions Ian Shipsey, Purdue University The CLEO Collaboration Albany, Carnegie Mellon, Cornell, Florida, Illinois, Kansas. Minnesota, Ohio-State, Pittsburgh, Purdue, Rochester, SMU, Syracuse, Texas PM, Vanderbilt, Wayne State yDoDo, DoK-p+ K+ K- p+ p-

  2. I am completely deaf • please write down your questions. • Pass them up to me • I will read out your question before answering it.

  3. CLEO-c : context SuperBaBar L =10 36 1010 BB/year CLEO Major contributions to B/c/ physics But, no longer competitive. Last Y(4S) run ended June 25 ‘01 BB /year year *BaBar/ Belle Numbers not updated since LP01 ON OFF CESR/CLEO 1.3 16.0 6.7 34 KEKB/Belle 4.5 29.1 3.7 62 PEPII/BABAR (*) 3.4 34.1 4.1 74

  4. CLEO-c : the context • Flavor Physics: is in “the sin2 era” akin to precision • Z. Over constrain CKM matrix with precision • measurements. Limiting factor: non-pert. QCD. This Decade LHC may uncover strongly coupled sectors in the physics 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. The Future Example: The Lattice Complete definition of pert & non. Pert.QCD. Matured over last decade, can calculate to 1-5% B,D,,… Charm at threshold can provide the data to calibrate QCD techniques  convert CESR/CLEO to a charm/QCD factory “CLEO-c/CESR-C”

  5. CLEO-c Physics Program • flavor physics: overcome the non pert. QCD roadblock • strong coupling inPhysics beyond the Standard Model • Physics beyond the Standard Model in unexpected places: • CLEO-c: precision charm abs. branching ratio measurements Semileptonic decays: Vcs Vcd unitarity & form factors Leptonic decays : decay constants Abs D hadronic Br’s normalize B physics Tests QCD techniques in c sector, apply to b sector • Improved Vub, Vcb, Vtd & Vts • CLEO-c: precise measurements of quarkonia spectroscopy & • decay provide essential data to calibrate theory. • CLEO-c: D-mixing, charm CPV, rare decays of charm and tau. CLEO-c will help build the tools to enable this decade’s flavor physics and the next decade’s new physics.

  6. The CKM Matrix • The parameters of the Standard Electroweak Model are: • The 4 quark mixing parameters reside in CKM matrix Weak eigenstates & fermion masses and mixings Mass eigenstates • * In SM , A, ,  are fundamental parameters • Does the CKM fully explain quark mixing? CP Violation? • To detect new physics in flavor changing sector must know CKM well • Must overdetermine the magnitude and phase of each element

  7. CKM Matrix Status Vud/Vud 0.1% Vus/Vus =1% Vub/Vub 25% l 1 l e l eig B n n n K n p p  Free/bound W cs Vcd/Vcd 7% Vcs/Vcs =16% Vcb/Vcb 5% l l B D n n l D D n K p Vtd/Vtd =36% Vtb/Vtb 29% Vts/Vts 39% 1 eib Bd Bd Bs Bs Vud, Vus and Vcb are the best determined due to flavor symmetries: I, SU(3), HQS. Charm (Vcd & Vcs) and rest of the beauty sector (Vub, Vtd, Vts) are poorly determined. Theoretical errors on hadronic matrix elements dominate.

  8. Importance of measuring fD & fDs: Vtd & Vts 1.8% ~15% (lattice) ~5% (lattice) Lattice predicts fB/fD & fBs/fDs with small errors if precision measurements of fD & fDs existed (they do not) could substitute in above ratios to obtain precision estimates of fB & fBs and hence precision determinations of Vtd and Vts Similarly fD/fDs checks fB/fBs

  9. Importance of absolute charm semileptonic decay rates |VCKM|2 |f(q2)|2 • Absolute magnitude & shape of form factors in PS PS & PS  V : stringent test of theory. Key input to ultra precise (5%) Vub vital CKM cross check of sin2 Absolute rate gives direct measurements of Vcd and Vcs / u   b HQS I d   c / Is related to at the same E(corrections O(1/M)) assume unitarity Measure in Dl : calibrate lattice to 1% Lattice error on ~ 3% expected unquenched (Cornell/FNAL) Extract Vub at BaBar/Belle using calibrated lattice calc. of But: need absolute Br(D l) and high quality neither exist

  10. Importance of precise absolute Charm Brs Vcb from zero recoil in B  D*  + CLEO LP01 Stat: 3.1% Sys 4.3% theory 4.6% Dominant Sys: slow (2.1%), form factors (1.4%) & B(DK) (1.3%) As B factory data sets grow, & theory improves charm Brs will become limiting systematic Vub/Vcb from at hadron machines requires: B(cpK) poorly known : 9.7% > B>3.0% at 90% C.L

  11. Importance of precise absolute Charm Brs HQET spin symmetry test since D*+p+Do is most useful mode need Do/D+ absolute rates (h is any light hadron) Test factorization with B  DDs Need Ds absolute Br Understanding charm content of B decay (nc) Precision Z bb and Z cc (Rb & Rc) At LHC/LC H  bb H  cc

  12. CESR-C • Modify for low energy operation: • add wigglers for transverse cooling (cost $4M) Expected machine performance: • Ebeam ~ 1.2 MeV at J/

  13. CLEO-c Proposed Run Plan 2002: Prologue: Upsilons ~1-2 fb-1 each at Y(1S),Y(2S),Y(3S),… Spectroscopy, matrix element, Gee, B hb 10-20 times the existing world’s data 2003: y(3770) – 3 fb-1 30 million DD events, 6 million tagged D decays (310 times MARK III) C L E O - c 2004: MeV – 3 fb-1 1.5 million DsDs events, 0.3 million tagged Ds decays (480 times MARK III, 130 times BES) 2005: y(3100), 1 fb-1 & y(3686) –1 Billion J/y decays (170 times MARK III, 20 times BES II) A 3 year program

  14. 1.5 T now,... 1.0T later 83% of 4p 87% Kaon ID with 0.2% p fake @0.9GeV 93% of 4p sp/p = 0.35% @1GeV dE/dx: 5.7% p @minI 93% of 4p sE/E = 2% @1GeV = 4% @100MeV CLEO III Detector  CLEO-c Detector Trigger: Tracks & Showers Pipelined Latency = 2.5ms Data Acquisition: Event size = 25kB Thruput < 6MB/s 85% of 4p For p>1 GeV

  15. How well does CLEO III work? 1st results from CLEO III data at LP01 Preliminary result using ~1/2 of the CLEO III data Clean K/  separation at ~2.5 GeV using RICH Rest of reconstruction technique similar to previous CLEO analyses B(B-D0K-) = ( 3.8 ±1.3) x10-4 CLEOIII (2.9 ± 0.8) x10-4 CLEO II Good agreement: between CLEO III & CLEO II

  16. 1st results from CLEO III data at LP01 Yield BR(BK)(x10-6) BK CLEOIII CLEO(1999) (Preliminary) Good agreement: between CLEOIII & CLEO II & with BaBar/Belle CLEO III works well

  17. A typical Y(4S) event: y(3770) events: simpler than Y(4S) events A typical y(3770) event: • CLEO III detector has • excellent tracking resolution • excellent photon resolution • maximum hermeticity • excellent particle id • flexible triggering • high throughput DAQ • The demands of doing physics in the 3-5 GeV range are easily met by the existing detector. • The CLEO Collaboration has a history of diverse interests spread over b, c, tau, resonance and QCD studies & great enthusiasm for CLEO-c • BUT: B Factories : 400 fb-1  500M cc by 2005, what is the advantage of running at threshold?

  18. Advantages of Running on Threshold Resonances • Charm events produced at threshold are extremely clean • Large , low multiplicity • Pure initial state: no fragmentation • Signal/Background is optimum at threshold • Double tag events are pristine • These events are key to making absolute branching fraction measurements • Neutrino reconstruction is clean • Quantum coherence aids D mixing and CP violation studies

  19. Analysis Tools • Our estimate of CLEO-C reach has been 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) TRKSIM GEANT

  20. Tagging Technique, Signal Purity • (3770) DD s ~4140  DsDs • Charm mesons have many large branching ratios (~1-15%) • High reconstruction eff •  high net tagging efficiency ~20% ! Anticipate 6M D tags 300K Ds tags: D Kp tag. S/B ~5000/1 ! Ds  (KK) tag. S/B ~100/1 MC MC Log scale! Log scale! Beam constrained mass

  21. Absolute Branching Ratios ~ Zero background in hadronic tag modes *Measure absolute Br (D X) with double tags Br = # of X/# of D tags # of D's is well determined Double tags are pristine MC Decay s L Double PDGCLEOc fb-1 tags (dB/B %) (dB/B%) D0K-p+ 3770 3 53,000 2.40.6 D+  K- p+p+ 3770 3 60,000 7.20.7 Ds fp 4140 3 6,000 251.9 dB/B Includes Stat, sys & bkgd errors CLEO-c sets absolute scale for all heavy quark measurements

  22. Absolute Branching Ratios CLEO ALEPH PDG CLEO-c CLEO MARK III PDG CLEO-c B(D0K-p+)% B(D+  K- p+p+)% CLEO PDG CLEO-c CLEO-c sets absolute scale for all heavy quark measurements B(Ds fp) %

  23. D meson Decay Constants |VCKM|2 |fD|2 l n Pseudoscalar decay constants: c and q can annihilate probability is  to wave function overlap B(D+l)/ D+ : fD+|Vcd| B(DS l)/ Ds : fDs|Vcs| * Charm lifetimes known 1-2% * 3 generation unitarity Vcs, (Vcd) known to 0.1% (1.1%)  fD+fDs

  24. D meson Decay Constants fDs has been measured by several groups, best CLEO: There are also two measurements from LEP using Dswith large errors fD+ < 290 MeV @ 90% CL (Mark III) The rates we have used for our estimates are:

  25. fDq from Absolute Br(Dq m+n) • Require one additional • charged track and no • additional photons • Measure absolute Br (Dq mn) • Fully reconstruct one D (tag)/event • Compute MM2 • Peaks at zero for Ds+  m+n • Expect resolution of ~Mpo m ID not used helps systematic error MC Ds  Ds tag D+ K Lmn D+  Ds mn D+ mn If MM2> 0, candidate for t+n

  26. Summary of Decay Constant Reach Branching Ratio Decay Constant

  27. Current Status of D semileptonic decays • Absolute Br’s poorly known dB/B- 5% - 73% • Vcs f+(0) measured for DKln: 0.79±0.01±0.04 (CLEO) • Shape of f+(q2), given by f+(0)/(1-q2/mp) measured for DKln: mp=2.00±0.12±0.18 GeV 2 • For DK*ln, ratios of form factors at q2=0 : Neither good accuracy nor agreement among experiments • Dpln & Drln: rates to ~20% accuracy

  28. Semileptonic Decay Reconstruction • Tagged events identify electron plus hadronic tracks • Kinematics at threshold cleanly separates signal from background Tagged Events Low Bkgd! 1.0 fb-1 25890 D0 pln D0 Kln 3730 D0 Kln 1.0 fb-1 Excellent separation ofDl DKl despite B(DKl )~10B( Dl)

  29. Calibration of the Lattice CLEO-C Lattice D0 pln D0 pln compare to lattice prediction ex: hep-ph/0101023 FNAL etal Note: lattice error large ~15% on normalization now, but in future few % predicted Excellent kinematic resolution at threshold I. Can test form factor shape directly II. Using Vcd from unitarity, can test normalization in D0 pln calibration good to ~1%

  30. Pseudoscalar to Vector transitions D+ K*0 e+ D+ - e+  1.0 fb-1 1.0 fb-1 Yet to be observed The four-fold joint angular decay distribution for DK*/l: Note: figure also applies to Dl.

  31. D+K*0e form factor determination rv = V/A1 r2 = A2/A1 CLEO-C 12 K events/3 fb-1 S/B~20/1 CLEO-C E791 3K S/B 5/1 (FOCUS 40K S/B 8/1) From CLEO-c determined abs Br Lifetime and unitarity: 1.0 fb-1 E791 PDG Br, Lifetime & unitarity Similarly, CLEO- will excel at Cabibbo suppressed modes De

  32. CLEO-c Impact semileptonic dB/B PDG CLEO-c CLEO-c will make significant improvements in the precision with which each absolute charm semileptonic branching ratiois known

  33. Determining Vcs and Vcd for the first time a complete set of charm PS  PS & PS  V absolute form factor magnitudes and slopes to a few% with ~zero bkgd in one experiment. Many internal cross checks, in the semileptonic sector invoke unitarity. Can combine with leptonic decays eliminating VCKM (D+ ln) / (D+ ln) independent of Vcd Test rate predictions at ~4% (Dsln) / (Dsln) independent of Vcs Test rate predictions at ~ 4.5% Test amplitudes at 2% Both tests important.Stringent test of theory! If theory passes the test…..

  34. Determining Vcs and Vcd Includes 3% Theory Error on rate- A challenge! gain confidence to (I) determine Vcs and Vcd from: Absolute branching ratios + lifetimes: Includes tracking EID and lifetime errors Tagged B/B (stat)  / (stat+sys) CLEO-c PDG 77670 0.4% 1.2% Vcs /Vcs = 1.6% 16% 11190 1.0% 1.5 % Vcd /Vcd =1.7% 7% Take ratio of like initial states form factors differ only by SU(3) breaking, no lifetime dependence, some cancellation of expt. Systematics + no requirement for theory to predict absolute rate R=Vcd /Vcs R/R 1.2% CLEO-c 2 % FOCUS II) Use CLEO-c validated lattice + B factory Br/p/h/lv for ultra precise Vub

  35. Unitarity Constraints |Vud|2 + |Vus|2 + |Vub|2 = 1 ?? With current values this test fails at 2.5 |Vcd|2 + |Vcs|2 + |Vcb|2 = 1 ?? With CLEO –c can test to ~3% Make the second row sensitivity comparable to the 1st row cu triangle |VubVcb*| |VudVcd*| Compare ratio of long sides to 1.3% Also major contributions to Vub Vcb Vtd Vts |VusVcs*|

  36. Compare to B factories f Ds FDs at a B factory Scale from CLEO analysis • Search for Ds* -> Dsg, Ds -> mn • Directly detect g, m, Use hermeticity of detector to reconstruct n • Backgrounds are LARGE! • Precision limited by systematics of background determination • FDs Error ~23% now (CLEO) • 400 fb-1~6-9% CLEO-c CLEO signal 4.8fb-1 Excess of m over e fakes Background measured with electrons Ds mn DM=Mmng -Mmn Mass Difference M GeV/c

  37. Compare to B Factories Do K-p+ CLEO • Method: Detect D*+p+Do, • when Do K-p+ and • Do  anything. • Problem: Systematic • Error due to background extrapolation • B/B = 3.6% • Expect limited improvements 2-3% CLEO-c Do K-p+ Double tagged a is  between thrust axis & slow p+ (4 of 8 intervals shown) Slow pion a thrust

  38. Comparison between B factories & CLEO-C BaBar 400 fb-1 CLEO-c 3 fb-1 Statistics limited abcdefghi Systematics & Background limited Current

  39. Compare to B Factories 2.3% 1.7% UL 14% 6 – 9 0.7% 1.9% 0.6% 2- 2% 0  Statistics limited. Systematics & background limited.

  40. Probes of New Physics • DD mixing • exploit coherence: • for mixing: no DCSD. •  rD=[(x2+y2)/2] < 0.01 @ 95%CL (KK, Kl,Kl) • CP violating asymmetries • Sensitivity: Acp < 0.01 • Unique:L=1,C=-1 CP tag one side, opposite side same CP • CP=±1 y(3770) CP=±1 = CPV • CP eigenstate tag X flavor mode • K+K- DCPy(3770) DCP K-p+ • Measure strong phase diff. cos ~0.05 CF DCSD • Needed for g from B  DK • Rare charm decays. Sensitivity: 10-6 D mix & DCPV suppressed in SM – all the more reason to measure them • y(3770)DD(C = -1) y(4140) gDD (C = +1) Gronau, Grossman, Rosner

  41. Probing QCD •  and  Spectroscopy • Masses, spin fine structure • Leptonic widths for S-states. • EM transition matrix elements • run on  resonances winter ’01-summer’02 ~ 4 fb-1 total • Uncover new forms of matter –gauge particles as constituents • Glueballs G=|gg  • Hybrids H=|gqq  • Requires detailed understanding of ordinary hadron spectrum in 1.5-2.5 GeV mass range. Verify tools for strongly coupled theories  Quantify accuracy for application to flavor physics Confinement, Relativistic corrections Wave function Tech: fB,K BK f D{s) Calibrate and test theoretical tech. Form factors J/ running 2005 Study fundamental states of the theory

  42. Gluonic Matter c ¯ c  1 X • Gluons carry color charge: should bind! • CLEO-c 1st high statistics experiment covering 1.5-2.5 GeV mass range. • find it or debunk it! • Radiative y decays are ideal • glue factory: • But, like Jim Morrison, glueballs have been sighted • too many times without confirmation.... • Huge data set • Modern detector • 95% of 4 coverage • perfect initial state • perfect tag • glue pair in color isosinglet • CLEO-c: 109 J/  ~60MJ/ X • Partial Wave analysis • Absolute BF’s: pp,KK,pp,,…

  43. The fJ(2220) :A case study ?? LEAR 1998 Glueballs are hard to pin down, often small data sets & large bkgds • K+K- BES (1996) • K0sK0s • K0sK0s MARKIII (1986) Crystal barrel: • pp K0sK0s

  44. fJ(2220) in CLEO-c? BES CLEO-C p+p- 74 32000 p 18 13000 K+K- 46 18600 KSKS 23 5300 pp 32 8500  – 5000 + + 0 0 K+ K- CLEO-c has corroborating checks: Anti-search in Two Photon Data: fJ2220 • CLEO II: B fJ (2220)/KSKS < 2.5(1.3) eV • CLEO III: sub-eV sensitivity • Upsilonium Data: (1S):Tens of events 2 3

  45. Inclusive Spectrum J/ X • Inclusive photon • spectrum a good place to search: • monochromatic • photons for each • state produced Unique advantages of CLEO-c + Huge data set +Modern 4 detector (Suppress hadronic bkg: J/X) +Extra data sets for corroboration , (1S): Lead to Unambiguous determination of J PC & gluonic content

  46. Comparison with Other Expts China: BES II is running now. BES II --> BES III upgrade BEPC I --> BEPC II upgrade, ~1032 2 ring design at 1033under consideration (workshop 10/01) Physics after 2006? if approval & construction go ahead. being proposed BES III Complimentary To CLEO-c HALL-D at TJNAL (USA) gp to produce states with exotic Quantum Numbers Focus on light states with JPC = 0+-, 1+-, … Complementary to CLEO-C focus on heavy states with JPC=0++, 2++, … Physics in 2007+ ? + HESR at GSI Darmstadt p p complementary, being proposed: physics in 2007?

  47. Additional topics Likely to be added to run plan • ’ spectroscopy (10 8 decays) ’chc…. • t+t- at threshold (0.25 fb-1) • measure mt to ± 0.1 MeV • heavy lepton, exotics searches • LcLc at threshold (1 fb-1) • calibrate absolute BR(LcpKp) • R=s(e+e- hadrons)/s(e+e- m+m-) • spot checks If time permits

  48. CLEO-c Physics Impact (what Snowmass said) • 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 Working Group) Imagine a World where we have theoretical mastery of non- perturbative QCD at the 2% level Now Theory errors = 2%

  49. CLEO-c Flavor Physics Impact (what Snowmass said) • 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. PDG PDG B Factory Data & CLEO-c Lattice Validation CLEO-c data and LQCD (Snowmass:E2 Working Group)

  50. Next Steps • CLEO-C workshop (May 2001) : successful • ~120 participants, 60 non-CLEO • Informational sessions with funding agencies & HEPAP • (April/May ‘01) : very positive response • Snowmass working groups E2/P2/P5 : acclaimed CLEO-c • CESR/CLEO Program Advisory Committee Sept 28. • endorsed CLEO-c • Proposal submission to NSF on October 15 2001 • See http://www.lns.cornell.edu/CLEO/CLEO-C/ • for project description • We welcome discussion and new members

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