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CLEO-c Collaboration: ~140 Scientists, 20 Institutions

Recent Results from CLEO-c & CESR-c: A New Frontier in Weak and Strong Interactions David Asner , University of Pittsburgh 15 June 2005, KAON05 at NWU. CLEO-c Collaboration: ~140 Scientists, 20 Institutions Carleton, Chicago, Carnegie Mellon, Cornell, Florida,

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CLEO-c Collaboration: ~140 Scientists, 20 Institutions

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  1. Recent Results from CLEO-c & CESR-c: A New Frontier in Weak and Strong InteractionsDavid Asner, University of Pittsburgh15 June 2005, KAON05 at NWU CLEO-c Collaboration: ~140 Scientists, 20 Institutions Carleton, Chicago, Carnegie Mellon, Cornell, Florida, George Mason, Illinois, Kansas, Luther, Northwestern, Minnesota, Pittsburgh, Puerto Rico, Purdue, Rochester, RPI, SMU, Syracuse, Vanderbilt, Wayne State

  2. CLEO-c The Context Flavor physics is in the “sin 2 era’ akin to precision Z. Over constrain CKM matrix with precision measurements. Discovery potential is limited by systematic errors from non-pert. QCD. This Decade LHC may uncover strongly coupled sectors in the physics beyond the Standard Model. The LC will study them. Strongly coupled field theories an outstanding challenge to theory. Critical need: reliable theoretical techniques & detailed data to calibrate them. The Future Complete definition of pert. and non-pert. QCD Goal: Calculate B, D, ,  to 5% in a few years, and a few % longer term. The Lattice Charm at threshold can provide the data to test & calibrate non-pert. QCD techniques  CLEO-c David Asner

  3. |VCKM|2 |f(q2)|2 Bd Bd Precision Quark Flavor Physics: Role of Charm 2005 The discovery potential of B physics is limited by systematic errors from QCD: Form factors in semileptonic (B) decay Decay constants in B mixing D system- CKM matrix elements are tightly constrained to <1% by unitarity • Measurements of absoluterates for leptonic and semileptonic D decays yielding decay constants and form factors to test QCD techniques.that can then be applied to the B system. + determinations of Vcs Vcd CLEO-c program In addition as Br(B D)~100% absolute D branching ratios normalize B physics. Probe of new physics: Dmixing, DCPV, D rare (& strong phases for CKM angle γ) David Asner Not covered today J/ probe of glueballs and exotics test of QCD

  4. |VCKM|2 |fD|2 l n Bd Bd Importance of measuring absolute charm leptonic branching ratios: fD & fDsVtd & Vts ~15% (LQCD) hep-lat/0409040 dfD+/fD+~100% PDG’04 Lattice predicts fB/fD with a small error If a precision measurement of fD existed (it does not) • Precision Lattice estimate of fB  precision determination of Vtd Similarly fD/fDs checks fB/fBs precise once Bs mixing seen David Asner

  5. |VCKM|2 |f(q2)|2  B l u b  D l c d Importance of Absolute Charm Semileptonic Decay Rates When Vub is determined from exclusive semileptonic (B) decay Stat sys form factor Unquenched LQCD or sum rules Expt. Error Charm semileptonic decays test form factor predictions unitary constrains |Vcd| to 1% HQS 1) Measure D form factor in Dl. Tests LQCD Dform factor calculation 2) BaBar/Belle can extract Vub using tested LQCD calc. of B form factor 3) Needs precise absolute Br(Dl) & high quality d(Dl)/dE neither exist David Asner

  6. Importance of precision absolute charm hadronic branching ratios Vcb zero recoil in B  D*l+ & B  Dl+ need B(DK) ALEPH, DELPHI,L3,OPAL.BABAR/BELLE,ARGUS/CLEO/CDF Lattice & sum rule (World Average Summer 2004) dB(DK)/dB(DK)  dVcb/Vcb=1.2% becomes significant As B Factory data sets grow, & calculation of F improve Test models of B decay ex: HQET & factorization: Understanding charm content of B decay (nc) Precision Z bb and Z cc (Rb & Rc) Now: several key charm branching ratios have errors between 7-26% At LHC/LC Hbb Hcc David Asner

  7. Ability to run at cms energies from J/y up to (5S) y’ y(3770) CLEO-c Detector:CESR-c Accelerator CLEO III CLEO-III CLEO-c SVX Mini Drift Chamber SVX • Simple conversion of detector from  (4S) to Y(3770) running • Addition of superconducting wigglers to CESR required for low energy running • Additional damping to compensate for lower synchrotron radiation Beam Energy (GeV) David Asner

  8. CLEO-c Run Plan & Status 2002: Prologue: Upsilons ~4 fb-1 at(1S),(2S),(3S) (combined) 10-20 times the existing world’s data (Nov 2001-Nov 2002) 2003: Installed 1 prototype wiggler spring ‘03 Took ~5 pb-1 atY(3770), 3 pb-1Y(2S) Installed ½ production wigglers summer’03 Pilot Run I: Y(3770), Y(2S), continuum 55.8 pb-1 3 pb-1 20.5 pb-1 Installed ½ production wigglers spring’04 Pilot Run II+III: only Y(3770) 225.3 pb-1 MACHINECONVERSION C L E O c Nominal CLEO-c Run Plan: 1 year at each of 1: (3770) 2: above Ds threshold 3: J/ A 3 year program PAC to advise on priorities of run plan: Nov ‘05 Scan of Ds threshold region later this summer David Asner

  9. e+e-y(3770)DD CLEO-c & D Tagging • Pure DD final state, no additional particles (ED = Ebeam). • Low particle multiplicity ~ 5-6 charged particles/event • Good coverage to reconstruct n in semileptonic decays • Pure JPC = 1- - initial state Tag one D meson in a selected tag mode. • Dictates whether final state is D+D- or D0D0 • Study decays of other D, (signal D) K Dsig e+ e- Dtag p p ED Ebeamimproves mass resolution by ~10X Analysis Preview • Leptonic Decays: Dtag + (Dsigmnm) • Semileptonic Decays: Dtag + (DsigXene), reconstruct ne using Pmiss • Hadronic Decays: double-tag yields & single-tag yields determine BR David Asner

  10. Summary of CLEO-c Impact • Leptonic Charm Decays – D+m+n, Ds+m+n,t+n • Measure decay constants fD, fDs ~few% • Improved fB possible from CLEO-c fD measurement + LQCD • Semileptonic Charm Decays – D0,D+K(*)ln, (p,r,w)ln - Ds+  K(*)ln, (h,f)ln • Measurements of |Vcs| and |Vcd| • Test theoretical form factor models • Impacts prediction of form factors for B meson decays • Important for |Vub| and |Vcb| • Hadronic Charm Decays – D0Kp, D+Kpp, Ds+fp • Important for |Vcb| • General Themes: • Charm measurements interesting in their own right • Calibration and validation of Lattice QCD • Improved measurement of many normalization modes for B physics David Asner

  11. l l Vud/Vud~0.1% Vus/Vus~1% e Vub/Vub~155% B n n K n n p p  Vcb/Vcb~53% Vcd/Vcd~71.1% Vcs/Vcs~161.4% l l D n B n l D K D n p Vtb/Vtb~29% Vtd/Vtd~365% Vts/Vts~395% W t b Bd Bd Bs Bs CLEO-c + Lattice QCD +B factories CLEO-c + Lattice QCD +B factories + ppbar CLEO-c Future of Precision Flavor Physics Goal: Measure all CKM matrix elements and associated phases in order to over-constrain the unitary triangles David Asner

  12. Selected CLEO-c Publications • Measuring B(D+  MU+ NU) and the Pseudoscalar Decay Constant f(D+). Phys.Rev.D70:112004,2004 (Paper on 55.8 pb-1, update with 281.1 pb-1 at LeptonPhoton2005) • Absolute Branching Fraction Measurements of Exclusive Charged D Semileptonic Decays - to be submitted to PRL, CLNS 05-1906 (Paper on 55.8 pb-1) • Absolute Branching Fraction Measurements of Exclusive Neutral D Semileptonic Decays - to be submitted to PRL, CLNS 05-1915 (Paper on 55.8 pb-1) • Inclusive D0/D+ Absolute Branching Fraction Measurements (results with 281.1 pb-1 at LeptonPhoton2005) • Measurement of Absolute Hadronic Branching Fractions of D Mesons and e+e-  DD Cross Sections at Ecm=3773 MeV submitted to PRL – hep-ex/0504003 (Paper on 55.8 pb-1) David Asner

  13. Leptonic Decays: D+→μ+ν David Asner

  14. fD+ from Absolute Br(D+  m+n) Tag D fully reconstructed ~9 pb-1 2390 tags 1 additional track (m) Compute missing mass2: peaks at 0 for signal ~33pb-1 5321 tags Mark III PRL 60, 1375 (1988) S=3 B=0.33 BESII Phys.Lett.B610:183-191, (2005) David Asner

  15. Many large BR tag modes ~25% efficiency for reconstructing a tag Signal is very pure after tagging 28651 +/-207 tag candidate Tag D m+ Signal D n • Tag D decay modes: • Fit for (“missing mass”)2: D Leptonic Decays: D+m+n Getting the ABSOLUTE branching fractions... “Other side D” tag e+ e- • Additional charged track presumed to be m+ David Asner

  16. Will also measure Ds+m+n in run above DsDs threshold D Leptonic Decays: D+m+n MC (~1.7 fb-1) Data (~60 pb-1) 8 candidate events First Observation! 1 background event in signal region Published in PRD Phys. Rev. D, 70, 112004 (2004) David Asner

  17. Comparison with LQCD + Models • BES • Lattice 2004 • CLEO-c • Isospin Mass Splittings • Potential Model • Rel. Quark Model • QCD Sum Rules • QCD Spectral Sum Rules • MILC • UKQCD Now: LQCD error ~10% CLEO-c error ~60 pb-1 22% ~280 pb-1 <10% error Eventually expect few % precision on fD+ & fDs David Asner

  18. Semileptonic Decays e |Vcs| , |Vcd| e+ W+ c • Test LQCD on shape of f+(q2)Use tested Lattice for norm.  Extract |Vcd|  Extract B(DXen) • Dp FF related to Bp FF by HQS  Precise Dp FF’s can lead to reducedstheory in |Vub| at B factories • Same holds for DVln, except 3 FF’s enter • Can also form ratios, where theory should be more precise David Asner

  19. Reconstruct one D meson in hadronic tagging channel Reconstruct the remaining observable tracks Use the missing energy (Emiss) and missing momentum (|Pmiss|) in the event to form kinematic fit variable for the neutrino Signal component from fit to variable U From Monte Carlo/Data From fit of Mbc and DE for number of tags Both flavors combined: Exclusive Semileptonic D Meson Decays Technique: David Asner

  20. K- K+ - e+ Semileptonic Decays CLNS 05-1906 and CLNS 05-1915 to be submitted to PRL Semileptonic decays are reconstructed with no kinematic ambiguity Hadronic Tags: 32K D+ 60K D0 (~1300 events) Events / ( 10 MeV ) Tagging creates a single D beam of known 4-momentum U = Emiss– |Pmiss| (GeV) David Asner

  21. More Cabibbo allowed modes 55.8 pb-1 Data csCabibbo Favored D+K*0e+n K*0K-p+ D+K0e+n (~550 events) (~420 events) Events / ( 10 MeV ) Events / ( 10 MeV ) U = Emiss– |Pmiss| (GeV) U = Emiss– |Pmiss| (GeV) D0 K*-e+n K*-K-p0 Historically Cabibbo allowed modes: provide a significant background to Cabibbo suppressed modes, making the latter particularly challenging….. (~90 events) Events / ( 10 MeV ) David Asner U = Emiss– |Pmiss| (GeV)

  22. Cabibbo suppressed modes 55.8 pb-1 Data (~110 events) Events / ( 10 MeV ) Note: kinematic separation. U = Emiss– |Pmiss| (GeV) Dm Tag with D*Dp Observable: Dm=mD*-mD. (~65 events) Compare to: state of the art measurement at 10 GeV (CLEO III) PRL 94, 11802 Events / ( 10 MeV ) U = Emiss– |Pmiss| (GeV) David Asner

  23. More Cabibbo supressed modes - 55.8 pb-1 D+r0e+n Only measurement until now S/N ~15/1 (~30 events) E791 Phys.Lett.B397: 325-332,(1997) Relative rate: S/N ~1/2 U = Emiss– |Pmiss| (GeV) D0r-e+n 1st Observation 1st Observation D0 K*-e+n K*-K-p0 D+we+n (~30 events) (5s) (8 events) U = Emiss– |Pmiss| (GeV) David Asner U = Emiss– |Pmiss| (GeV)

  24. Exclusive Semileptonic D Decays Now (55.8 pb-1): Preliminary CLEO-c already all modes more precise than PDG. to be submitted to PRL Will also measure D+sK0e+n,K*0e+n,fe+n in run above DsDs threshold David Asner

  25. |Vcs| or |Vcd| e+ W+ c Assuming a precision of ~3% for the SL form factors and ~1% for the decay constants is achieved by the theory: • Error on |Vcd| of ~few% (presently 7%) from D+m+n and Dpen • Error on |Vcs| of ~few% (presently 16%) from Ds+m+n, Ds+t+n and DKln Decay Constants, FF, |Vcs| and |Vcd| Use ratio of semileptonic to leptonic branching ratios to eliminate CKM element and isolate hadronic terms: Theory is calibrated/tested with this data David Asner

  26. pen Ken (PRL 94, 011601(2005) Differential Semileptonic Rates PPen rate shape STATUS 2005 (CLEO III FOCUS BES II) CLEO PRL 94/, 11802 First unquenched LQCD for D/K e  LQCD : shape & rate correct: precision~10% D0→π-e+ν D0→K-e+ν CLEO-c (1) No kinematic ambiguity (2) rest frame of D q2 resolution x 16 better Raw q2No efficiency correction David Asner

  27. Testing the Lattice with (semi)leptonic Charm Decays CLEO-c MC Lattice QCD D0 pln D0 pln D0 pln 1fb-1 1fb-1 D0Kln CLEO-c MC U = Emiss - Pmiss CLEO-c: PS  PS & PS  V absolute form factor magnitudes & slopes to a few%. Stringent test of theory! (Unique) (D+ ln) / (D+ ln) independent of Vcd tests amplitudes ~few% (DsKln) / (Dsln) independent of Vcs tests amplitudes ~ few% Vcs/Vcs=few%(now~11%) Vcd/Vcd=few%(now: 5.4%) Then Tested lattice to calc. Bpln is available for precise exclusive Vub David Asner

  28. Preliminary CLEO-c (in D rest frame) Inclusive Semileptonic D Decays David Asner

  29. Tag opposite side D meson Identify electron Select correct e charge using opposite side D meson: Charge of K for D0 D meson charge for D+/- Correct for electron efficiency and backgrounds Efficiency from re-weighted radiative Bhabhas Fake rates Inclusive Semileptonic D Decays Technique: CLEO-c (stat.) <0.2% <0.2% David Asner

  30. Independent of integrated luminosity! Submitted to PRL hep-ex/0504003 Hadronic D Decays Single tagged Double tagged DXj DX e+ e- e+ e- DXi DXi David Asner

  31. D Hadronic BR’s & Production Cross Sections Fitting technique • A simultaneous fit for all BR and cross sections is performed • Charged and neutral modes fit simultaneously • All correlations taken into account • Efficiencies • Denominator of efficiency may be determined using missing mass in data and MC • Data-MC agreement on the order of <0.2% for charged tracks • MC-data agreement for p0 and K0s efficiencies still undergoing refinements • Include effects of final state radiation (FSR) David Asner

  32. Absolute Charm Branching Ratios at Threshold s(MBC) ~ 1.3 MeV, x2 withp0 s(DE) ~ 7—10 MeV, x2 withp0 Kinematics analogous to (4S)BB: identify D with Double tags Single tags 15120±180 377±20 D candidate mass (GeV) D candidate mass (GeV) Independent of L and cross section David Asner

  33. Single tags Double tags 3 D0 Modes 6 D+ Modes D0 2484±51 (combined) D+ 1650±42 (combined) (log scale)! Signal shape: y(3770) line shape, ISR, beam energy spread & momentum resolution, Bgkd: ARGUS Global fit pioneered by Mark III NDD & Bi’s extracted from single and double tag yields with c2 minimization technique. David Asner

  34. D+ Modes D0 Modes submitted to PRL Stat. errors: ~2.0% neutral, ~2.5% charged s(systematic) ~ s(statistical). six modes more precise than PDG.  syst. dominates Many systematics evaluated using data so will shrink as L Normalized to PDG David Asner s(DD)=6.390.10+0.17–0.08 nb

  35. Comparison with PDG 2004 THEN: DoK-p+ CLEO & ALEPH D*+p+Do, Do K-p+ compare to: D*+p+Do, Do  unobserved (Q~6MeV) p+  thrust CLEO-c as precise as any previous measurement NOW: CLEO-c David Asner

  36. B(D+K-p+p+) THEN: Method (CLEO) Bootstrap: Measure: Most precise Assume isospin Conclusion: the charm hadronic scale we have been using for last 10 years is approximately correct NOW: David Asner CLEO-c will set absolute scale for all heavy quark measurements

  37. Impact of CLEO-c Measurements • Results from ~55.8 pb-1: Accumulated ~281 pb-1 • Leptonic Charm Decays – D+m+n, Ds+m+n,t+n • Measure decay constants fD, fDs ~few% • Improved fB possible from CLEO-c fD measurement + LQCD • Semileptonic Charm Decays – D0,D+K(*)ln, (p,r,w)ln - Ds+  K(*)ln, (h,f)ln • Measurements of |Vcs| and |Vcd| • Test theoretical form factor models • Impacts prediction of form factors for B meson decays • Important for |Vub| and |Vcb| • Hadronic Charm Decays – D0Kp, D+Kpp, Ds+fp • Important for |Vcb| PDG PDG CLEO-c data and LQCD B-Factory/Tevatron Data & CLEO-c Lattice Validation David Asner

  38. CLEO-c Impact on Unitarity Triangle Now: Theory uncertainties dominate With few % theory errors made possible by CLEO-c and 500 fb-1 each from the B factories: David Asner

  39. Summary CLEO-c 1st data (6 wigglers) summer presented in summer 2004. Detector performing well, data is excellent quality & is well understood. fD+ is now known to 22% (was 100% in PDG’04, <10% at LP2005) D0-e+ now 14% (was 45%), 1st observations: D0 e+, D+ e+ Most precise measurements of D+ K-++ Several % precision in all key charm quantities, + probe for new physics & glueballs Lattice goal: Calculate in D,B,, to 5% in few years & few% longer term CLEO-c about to provide few % tests of lattice calculations (& other QCD techniques) in D system & in onia, quantifying the accuracy for application of LQCD to the B system • BABAR/Belle/CDF/D0 (later LHC-b/ATLAS/CMS SuperKEKb) + theory can reach few % precision for Vtd, Vts, γ and exclusive Vub,Vcb. CLEO-c maximizes the sensitivity of the worldwide heavy quark flavor physics program to new physics this decade and paves the way for understanding beyond the Standard Model physics at the LHC/LC. David Asner

  40. Other CLEO Physics Not Covered (3770) • Search for CPV, rare decays DKee, mixing • Rich program of Dalitz plot analyses important for CKM angle g • Measurement of D0/D0 relative strong phase • Separate measurements of B(D->K S,Lp) • Search for nonDD final states ’ + other charmonia... lots of results • Observation of hc, photon transitions, 2-photon width cc2 • ’XJ/, VP, multibody, baryon-anti-baryon • J/ di-leptons Bottomonia from 2002 run • (1-3S)ggg, LFV, (1S) gh+h-,gp0p0,gh,gh’ , Gee • c’b->cb transitions • hidden beauty to open charm David Asner

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