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1 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.

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Presentation on theme: "1 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."— Presentation transcript:

1 1 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, George Mason, Illinois, Kansas, Luther, Northwestern, Minnesota, Pittsburgh, Puerto Rico, Purdue, Rochester, RPI, SMU, Syracuse, Vanderbilt, Wayne State

2 15 June 2005, KAON05David Asner 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. 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. Complete definition of pert. and non-pert. QCD Goal: Calculate B, D,,  to 5% in a few years, and a few % longer term. Charm at threshold can provide the data to test & calibrate non-pert. QCD techniques  CLEO -c This Decade The Future The Lattice

3 15 June 2005, KAON05David Asner 3 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 absolute rates 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 Precision Quark Flavor Physics: Role of Charm BdBd BdBd In addition as Br(B  D)~100% absolute D branching ratios normalize B physics. |f(q 2 )| 2 |V CKM | 2 CLEO-c program Probe of new physics: Dmixing, DCPV, D rare (& strong phases for CKM angle γ) J/  probe of glueballs and exotics test of QCD Not covered today

4 15 June 2005, KAON05David Asner 4 Lattice predicts f B /f D with a small error If a precision measurement of f D existed (it does not)  Precision Lattice estimate of f B  precision determination of V td Similarly f D /f Ds checks f B /f Bs  precise once B s mixing seen Importance of measuring absolute charm leptonic branching ratios: f D & f Ds  V td & V ts ~15% (LQCD) hep-lat/0409040 BdBd BdBd |f D | 2 |V CKM | 2  f D+ /f D+ ~100% PDG’04

5 15 June 2005, KAON05David Asner 5 |f(q 2 )| 2 |V CKM | 2 HQS 1) Measure D  form factor in D  l. Tests LQCD D  form factor calculation 2) BaBar/Belle can extract V ub using tested LQCD calc. of B  form factor 3) Needs precise absolute Br(D  l ) & high quality d  (D  l )/dE  neither exist b u l  B c d l  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%

6 15 June 2005, KAON05David Asner 6 Importance of precision absolute charm hadronic branching ratios As B Factory data sets grow, & calculation of F improve dB(D  K  )/dB(D  K  )  dV cb /V cb =1.2% V cb zero recoil in B  D*l + & B  Dl + Lattice & sum rule ALEPH, DELPHI,L3,OPAL.BABAR/BELLE,ARGUS/CLEO/CDF Test models of B decay ex: HQET & factorization: Understanding charm content of B decay (n c ) Precision Z  bb and Z  cc (R b & R c ) At LHC/LC H  bb H  cc (World Average Summer 2004) Now: several key charm branching ratios have errors between 7-26% need B(D  K  ) becomes significant

7 15 June 2005, KAON05David Asner 7 CLEO-c Detector:CESR-c Accelerator SVX CLEO III  Ability to run at cms energies from J/  up to  (5S) Beam Energy (GeV) CLEO-III SVX Mini Drift Chamber CLEO-c  (3770) ’’ Addition of superconducting wigglers to CESR required for low energy running –Additional damping to compensate for lower synchrotron radiation Simple conversion of detector from  (4S) to  (3770) running

8 15 June 2005, KAON05David 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) Nominal CLEO-c Run Plan: 1 year at each of 1:  (3770) 2: above Ds threshold 3: J/  CLEOcCLEOc A 3 year program 2003: Installed 1 prototype wiggler spring ‘03 Took ~5 pb -1 at  (3770), 3 pb -1  (2S) Installed ½ production wigglers summer’03 Pilot Run I:  (3770),  (2S), continuum 55.8 pb -1 3 pb -1 20.5 pb -1 Installed ½ production wigglers spring’04 Pilot Run II+III: only  (3770) 225.3 pb -1 MACHINE CONVERSION Scan of D s threshold region later this summer PAC to advise on priorities of run plan: Nov ‘05

9 15 June 2005, KAON05David Asner 9 CLEO-c & D Tagging D tag D sig K   Tag one D meson in a selected tag mode.  Dictates whether final state is D + D - or D 0 D 0  Study decays of other D, (signal D) E D  E beam improves mass resolution by ~10X e+e+ e + e -   (3770)  DD e-e-  Pure DD final state, no additional particles (E D = E beam ).  Low particle multiplicity ~ 5-6 charged particles/event  Good coverage to reconstruct in semileptonic decays  Pure J PC = 1 - - initial state  Leptonic Decays: D tag + (D sig    )  Semileptonic Decays: D tag + (D sig  Xe e ), reconstruct e using P miss  Hadronic Decays: double-tag yields & single-tag yields determine BR Analysis Preview

10 15 June 2005, KAON05David Asner 10 Summary of CLEO-c Impact  Leptonic Charm Decays – D+  +, D s +   +,  +  Measure decay constants fD, fDs ~few%  Improved f B possible from CLEO-c f D measurement + LQCD  Semileptonic Charm Decays – D 0,D+  K (*) l, (  l - D s +  K (*) l, (  )l  Measurements of |V cs | and |V cd |  Test theoretical form factor models  Impacts prediction of form factors for B meson decays  Important for |V ub | and |V cb |  Hadronic Charm Decays – D 0  K , D+  K , D s +   Important for |V cb |  General Themes:  Charm measurements interesting in their own right  Calibration and validation of Lattice QCD  Improved measurement of many normalization modes for B physics

11 15 June 2005, KAON05David Asner 11 CLEO-c + Lattice QCD +B factories + ppbar CLEO-c + Lattice QCD +B factories CLEO-c Future of Precision Flavor Physics  Vub/Vub~15  5% l B  l D   Vcd/Vcd~7  1.1% l D   Vcs/Vcs~16  1.4% l B D  Vcb/Vcb~5  3% BdBd BdBd  Vtd/Vtd~36  5% BsBs BsBs  Vts/Vts~39  5%  Vtb/Vtb~29%  Vus/Vus~1%   l  Vud/Vud~0.1% e p n t b W Goal: Measure all CKM matrix elements and associated phases in order to over-constrain the unitary triangles

12 15 June 2005, KAON05David 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 )

13 15 June 2005, KAON05David Asner 13 Leptonic Decays: D + → μ + ν

14 15 June 2005, KAON05David Asner 14 f D+ from Absolute Br(D +    ) 1 additional track (  ) Compute missing mass 2 : peaks at 0 for signal Tag D fully reconstructed Mark III PRL 60, 1375 (1988 ) ~9 pb -1 2390 tags ~33pb -1 5321 tags S=3 B=0.33 BESII Phys.Lett.B610:183-191, (2005)

15 15 June 2005, KAON05David Asner 15 D Leptonic Decays: D +   +  Many large BR tag modes  ~25% efficiency for reconstructing a tag  Signal is very pure after tagging  28651 +/-207 tag candidate Getting the ABSOLUTE branching fractions... “Other side D” tag e+e+ e-e- Signal D ++ Tag D  Tag D decay modes:  Fit for (“missing mass”) 2 : Additional charged track presumed to be  +

16 15 June 2005, KAON05David Asner 16 D Leptonic Decays: D +   + Published in PRD Phys. Rev. D, 70, 112004 (2004) Will also measure D s +   + in run above D s D s threshold Data (~60 pb -1 ) First Observation! 8 candidate events 1 background event in signal region MC (~1.7 fb -1 )

17 15 June 2005, KAON05David 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 f D+ & f Ds

18 15 June 2005, KAON05David Asner 18 Semileptonic Decays c e+e+ e W+W+ |V cs |, |V cd |  Test LQCD on shape of f + (q 2 )  Use tested Lattice for norm.  Extract |V cd |  Extract B(D  Xe )  D   FF related to B   FF by HQS  Precise D   FF’s can lead to reduced  theory in |V ub | at B factories  Same holds for D  Vln, except 3 FF’s enter  Can also form ratios, where theory should be more precise

19 15 June 2005, KAON05David Asner 19 Exclusive Semileptonic D Meson Decays  Reconstruct one D meson in hadronic tagging channel   Reconstruct the remaining observable tracks  Use the missing energy (E miss ) and missing momentum (|P miss |) in the event to form kinematic fit variable for the neutrino Technique: From fit of M bc and  E for number of tags Signal component from fit to variable U From Monte Carlo/Data Both flavors combined:

20 15 June 2005, KAON05David Asner 20 K-K- -- e+e+ K+K+ Semileptonic Decays Tagging creates a single D beam of known 4-momentum Semileptonic decays are reconstructed with no kinematic ambiguity Hadronic Tags: 32K D + 60K D 0 Events / ( 10 MeV ) (~1300 events) U = E miss – |P miss | (GeV) CLNS 05-1906 and CLNS 05-1915 to be submitted to PRL

21 15 June 2005, KAON05David Asner 21 More Cabibbo allowed modes U = E miss – |P miss | (GeV) Events / ( 10 MeV ) (~550 events) U = E miss – |P miss | (GeV) c  s Cabibbo Favored 55.8 pb -1 Data (~90 events) (~420 events) Historically Cabibbo allowed modes: provide a significant background to Cabibbo suppressed modes, making the latter particularly challenging….. D +  K 0 e + D +  K *0 e + K *0  K -  + D 0  K *- e + K *-  K -  0

22 15 June 2005, KAON05David Asner 22 Cabibbo suppressed modes U = E miss – |P miss | (GeV) Events / ( 10 MeV ) (~110 events) Events / ( 10 MeV ) (~65 events) U = E miss – |P miss | (GeV) 55.8 pb -1 Data Compare to: state of the art measurement at 10 GeV (CLEO III) PRL 94, 11802 Note: kinematic separation. Tag with D*  Dp Observable:  m=mD*-mD. mm

23 15 June 2005, KAON05David Asner 23 U = E miss – |P miss | (GeV) (~30 events) U = E miss – |P miss | (GeV) (~30 events) (8 events) (5  ) 1 st Observation E791 Phys.Lett.B397: 325-332,(1997) Relative rate: S/N ~1/2 S/N ~15/1 More Cabibbo supressed modes - 55.8 pb -1 Only measurement until now D +  e + D +   e + D 0   e + D 0  K *- e + K *-  K -  0 U = E miss – |P miss | (GeV)

24 15 June 2005, KAON05David Asner 24 Exclusive Semileptonic D Decays Preliminary Now (55.8 pb -1 ): Will also measure D + s  K 0 e +,K* 0 e +,  e + in run above D s D s threshold CLEO-c already all modes more precise than PDG. to be submitted to PRL

25 15 June 2005, KAON05David Asner 25 Decay Constants, FF, |V cs | and |V cd | c e+e+ W+W+ |V cs | or |V cd | Use ratio of semileptonic to leptonic branching ratios to eliminate CKM element and isolate hadronic terms: Theory is calibrated/tested with this data Assuming a precision of ~3% for the SL form factors and ~1% for the decay constants is achieved by the theory: Error on |V cd | of ~few% (presently 7%) from D +   + and D   e Error on |V cs | of ~few% (presently 16%) from D s +   +, D s +   + and D  Kl

26 15 June 2005, KAON05David Asner 26 Differential Semileptonic Rates P  Pe D 0 →K - e + ν D0→π-e+νD0→π-e+ν Raw q 2  No efficiency correction CLEO PRL 94/, 11802 (PRL 94, 011601 (2005) STATUS 2005 (CLEO III FOCUS BES II) LQCD : shape & rate correct: precision~10% (1) No kinematic ambiguity (2) rest frame of D q 2 resolution x 16 better  e Ke CLEO-c shape rate First unquenched LQCD for D  /K e

27 15 June 2005, KAON05David Asner 27 U = E miss - P miss CLEO-c: PS  PS & PS  V absolute form factor magnitudes & slopes to a few%. Stringent test of theory! (Unique) D 0  l D 0  Kl CLEO-c MC Lattice QCD D 0   l CLEO-c MC 1fb -1  (D +  l  (D +  l  independent of Vcd tests amplitudes ~few%  (D s  Kln) /  (D s  l ) independent of Vcs tests amplitudes ~ few%  Vcs/Vcs=few%(now~11%)  Vcd/Vcd=few%(now: 5.4%) Testing the Lattice with (semi)leptonic Charm Decays Then Tested lattice to calc. B  l  is available for precise exclusive Vub 1fb -1

28 15 June 2005, KAON05David Asner 28 Inclusive Semileptonic D Decays Preliminary CLEO-c (in D rest frame)

29 15 June 2005, KAON05David Asner 29 Inclusive Semileptonic D Decays  Tag opposite side D meson  Identify electron  Select correct e charge using opposite side D meson:  Charge of K for D 0  D meson charge for D +/-  Correct for electron efficiency and backgrounds  Efficiency from re- weighted radiative Bhabhas  Fake rates Technique: CLEO-c (stat.) <0.2%

30 15 June 2005, KAON05David Asner 30 Hadronic D Decays e+e+ e-e- DXDX Single taggedDouble tagged e+e+ e-e- DXjDXj DXiDXi DXiDXi Independent of integrated luminosity! Submitted to PRL hep-ex/0504003

31 15 June 2005, KAON05David 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 p 0 and K 0 s efficiencies still undergoing refinements  Include effects of final state radiation (FSR)

32 15 June 2005, KAON05David Asner 32 Absolute Charm Branching Ratios at Threshold Independent of L and cross section Single tags D candidate mass (GeV) Double tags D candidate mass (GeV) Kinematics analogous to  (4S)  BB: identify D with  (M BC ) ~ 1.3 MeV, x2 with  0  (  E) ~ 7—10 MeV, x2 with  0 15120 ± 180 377 ± 20

33 15 June 2005, KAON05David Asner 33 (log scale)! 2484 ± 51 (combined) 1650 ± 42 (combined) 6 D + Modes 3 D 0 Modes Single tagsDouble tags Signal shape:  (3770) line shape, ISR, beam energy spread & momentum resolution, Bgkd: ARGUS Global fit pioneered by Mark III N DD & B i ’s extracted from single and double tag yields with  2 minimization technique. D 0 D +

34 15 June 2005, KAON05David Asner 34 submitted to PRL  Stat. errors: ~2.0% neutral, ~2.5% charged   (systematic) ~  (statistical).  syst. dominates Many systematics evaluated using data so will shrink as  L D 0 Modes D + Modes Normalized to PDG six modes more precise than PDG.  (DD)=6.39  0.10 +0.17 –0.08 nb

35 15 June 2005, KAON05David Asner 35 Comparison with PDG 2004 B (%)Error(%)Source 3.82  0.07  0.1 3.6CLEO 3.82  0.09  0.1 3.8ALEPH 3.80  0.09 2.4PDG 3.91  0.08  0.09 3.1CLEO-c CLEO & ALEPH D* +  + D o, D o  K -  + compare to: D* +  + D o, D o  unobserved (Q~6MeV) THEN: NOW: Do K-+Do K-+ CLEO-c as precise as any previous measurement ++ thrust  CLEO-c

36 15 June 2005, KAON05David Asner 36 CLEO-c will set absolute scale for all heavy quark measurements B (%)Error(%)Source 9.3  0.6  0.8 10.8CLEO 9.1  1.3  0.4 14.9MKIII 9.1  0.7 7.7PDG 9.52  0.25  0.27 3.9CLEO-c Method (CLEO) Bootstrap: Measure: THEN: Assume isospin NOW: B(D +  K -      Conclusion: the charm hadronic scale we have been using for last 10 years is approximately correct Most precise

37 15 June 2005, KAON05David Asner 37 Impact of CLEO-c Measurements  Results from ~55.8 pb -1 : Accumulated ~281 pb -1  Leptonic Charm Decays – D+  +, D s +   +,  +  Measure decay constants fD, fDs ~few%  Improved f B possible from CLEO-c f D measurement + LQCD  Semileptonic Charm Decays – D 0,D+  K (*) l, (  l - D s +  K (*) l, (  )l  Measurements of |V cs | and |V cd |  Test theoretical form factor models  Impacts prediction of form factors for B meson decays  Important for |V ub | and |V cb |  Hadronic Charm Decays – D 0  K , D+  K , D s +   Important for |V cb | VcdVcsVcbVubVtdVts 7%16% 5%15%36%39% few% PDG B-Factory/Tevatron Data & CLEO-c Lattice Validation PDG CLEO-c data and LQCD

38 15 June 2005, KAON05David 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:

39 15 June 2005, KAON05David Asner 39 Summary CLEO-c 1 st data (6 wigglers) summer presented in summer 2004. Detector performing well, data is excellent quality & is well understood. f D+ is now known to 22% (was 100% in PDG’04, <10% at LP2005) D 0  - e + now 14% (was 45%), 1st observations: D 0  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.

40 15 June 2005, KAON05David 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   Measurement of D 0 /D 0 relative strong phase  Separate measurements of B(D->K S,L  )  Search for nonDD final states  ’ + other charmonia... lots of results  Observation of h c, photon transitions, 2-photon width  c2   ’  XJ/ , VP, multibody, baryon-anti-baryon  J/   di-leptons Bottomonia from 2002 run   (1-3S)   gg, LFV,  (1S)   h+h-,  0  0, ,  ’,  ee   ’ b ->  b transitions  hidden beauty to open charm


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