1 Recent Results from CLEO-c & CESR-c: A New Frontier in Weak and Strong Interactions David Asner,...

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

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


2005

The discovery potential of B physics is limited by systematic errors from QCD:

Form factors in semileptonic (B) decay ,ub cbV V

Decay constants in B mixing ,td tsV V

D system- CKM matrix elements are tightly constrained to <1% by unitarityMeasurements of absolute rates for leptonic and semileptonic D decays

yielding decay constants and form factors to test QCD techniques.thatcan then be applied to the B system. + determinations of Vcs Vcd

Precision Quark Flavor Physics: Role of Charm

Bd Bd

In addition as Br(B D)~100% absolute D branching ratios normalize B physics.

|f(q2)|2

|VCKM|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


Lattice predicts fB/fD with a small errorIf 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

Importance of measuring absolute charm leptonic branching ratios: fD & fDsVtd & Vts

2 2 2( .) Bd td tbV Vra n fte co st

1.0%

(expt)

Winter 2005

td tbV V

if was known to 3%

would be known to ~5%Bdf

tdV1

ubV

~15% (LQCD)hep-lat/0409040

Bd Bd

22( ) / ( .)D cdD

B D const f V

|fD|2

|VCKM|2

s inaccessible

accessibleBd B

D Ds

f f

f f

td tsV / V

known from unitarity to 1%cdV

~ 16%

D

fD+/fD+~100%

PDG’04


|f(q2)|2

|VCKM|2

HQS

1) Measure D form factor in Dl. Tests LQCD D form factor calculation2) BaBar/Belle can extract Vub using tested LQCD calc. of B form factor3) Needs precise absolute Br(Dl) & high quality d(Dl)/dE neither exist

2 D 2 2cd2

|V | |f (q )|q

d

d

b u l B

c dl D

Importance of Absolute Charm Semileptonic Decay Rates

When Vub is determined from

exclusive semileptonic (B) decay

(5.1% 6.0% 12.6%)| |

ub

ub

V

V

Stat sys form factorUnquenched LQCD or sum rulesExpt. Error

2 B 2 2ub2

|V | |f (q )|q

d

d

~ 45%

PDG04

B

B

Charm semileptonic decaystest form factor predictions

2 2

&

16 representative

error budget for new

analysis

Belle BABAR B l

q GeV

BABAR

unitary constrains |Vcd| to 1%


3exp(41.4 1.0 1.8 ) 10cb theoV

Importance of precision absolute charm hadronic branching ratios

As B Factory data sets grow, & calculation of F improve

dB(DK)/dB(DK) dVcb/Vcb=1.2%

Vcb zero recoil in B D*l+ & B Dl+

2* 2 22

( ) ( ) cb

dB D F q V

dq

2 2max( ) 0.91 0.04F q q

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 (nc)

Precision Z bb and Z cc (Rb & Rc)

At LHC/LC Hbb Hcc

(World Average Summer 2004)

Now: several key charm branchingratios have errors between 7-26%

need B(DK)

becomessignificant


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

SVXMini DriftChamber

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


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 of1: (3770) 2: above Ds threshold 3: J/

CLEOc

A 3 yearprogram

2003: Installed 1 prototype wiggler spring ‘03 Took ~5 pb-1 at (3770), 3 pb-1 (2S) Installed ½ production wigglers summer’03Pilot Run I: (3770), (2S), continuum

55.8 pb-1 3 pb-1 20.5 pb-1

Installed ½ production wigglers spring’04Pilot Run II+III: only (3770) 225.3 pb-1

MACHINECONVERSION

Scan of Ds threshold region later this summer

PAC to advise on priorities of run plan: Nov ‘05


CLEO-c & D Tagging

Dtag

Dsig

K

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)

2 2

| |

bc beam D

beam D

miss miss

M E p

E E E

U E P

ED Ebeam improves mass resolution by ~10X

e+

e+e- (3770)DD

e-

Pure DD final state, no additional particles (ED = Ebeam). Low particle multiplicity ~ 5-6 charged particles/event Good coverage to reconstruct in semileptonic decays Pure JPC = 1- - initial state

Leptonic Decays: Dtag + (Dsig ) Semileptonic Decays: Dtag + (Dsig Xee), reconstruct e using Pmiss

Hadronic Decays: double-tag yields & single-tag yields determine BR

Analysis Preview


Summary of CLEO-c Impact

Leptonic Charm Decays – D++, Ds+ +,+ Measure decay constants fD, fDs ~few% Improved fB possible from CLEO-c fD measurement + LQCD

Semileptonic Charm Decays – D0,D+K(*)l, (l - Ds+ K(*)l, ()l

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 – D0K, D+K, Ds+ 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


CLEO-c + Lattice QCD +B factories + ppbar

CLEO-c + Lattice QCD +B factories

CLEO-c

Future of Precision Flavor Physics

Vub/Vub~155%lB

l

D

Vcd/Vcd~71.1%lD

Vcs/Vcs~161.4%

l

B D

Vcb/Vcb~53%

Bd Bd

Vtd/Vtd~365%

Bs Bs

Vts/Vts~395% Vtb/Vtb~29%

Vus/Vus~1%

l Vud/Vud~0.1%

e

pn

t

b

W

Goal: Measure all CKM matrix elements and associated phases in order to over-constrain the unitary triangles


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)


Leptonic Decays: D+→μ+ν

2

2222 2

218

lFl cdD D

D

mGD l f m M V

M


fD+ from Absolute Br(D+ )

1 additional track ()Compute missing mass2: peaks at 0 for signal

Tag D fully reconstructed

Mark III PRL 60, 1375 (1988)

~9 pb-1 2390 tags

4

11.1 12953 119

( ) 10 MeV

MkIII 7.2 290

BESII 12.2 0.11 371 25

DB D f

~33pb-1

5321 tags

S=3 B=0.33

BESII Phys.Lett.B610:183-191, (2005)

p

MKIII

BESII


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-

Signal D+

Tag D

Tag D decay modes:

00

0

0

0

S

S

S

KD

KD

KD

KD

KD

22beam

2MM ppEED

• Fit for (“missing mass”)2:

• Additional charged track presumed to be +


D Leptonic Decays: D++

MeV 1741202

106.04.15.3 4

Df

DB Published in PRDPhys. Rev. D, 70, 112004 (2004)

Will also measure Ds++ in run above DsDs threshold

Data (~60 pb-1)

First Observation!

0LK

8 candidate events1 background event in signal region

MC (~1.7 fb-1)


Comparison with LQCD + Models

150 180 210 240 270 300 330 360 390 420 450 480 510

Charged D Decay Constant (MeV)

• 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


Semileptonic Decays

c

e+

e

W+

, s d

,u d

|Vcs| , |Vcd|

,u d

Test LQCD on shape of f+(q2) Use tested Lattice for norm. Extract |Vcd|

Extract B(DXe)

D FF related to B FF by HQS Precise D FF’s can lead to reduced theory in |Vub| at B factories

Same holds for DVln, except 3 FF’s enter

Can also form ratios, where theory should be more precise

223

322

24qf

pVGPlD

cqF


Exclusive Semileptonic D Meson Decays

)()(

)()( 0

00

DNeK

eKNeKDB

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

Technique:

22candidatebeambc PEM

candidatebeam EEE

missPEU

miss

From fit of Mbc

and E for number of tags

Signal componentfrom fit to variable U

From MonteCarlo/Data

))()(()(

)()(0

00

DNDNeK

eKNeKNB

Both flavors combined:


K-

-

e+

K+

Semileptonic Decays

Tagging creates a single D beam of known 4-momentum

Semileptonic decays are reconstructed with nokinematic ambiguity

Hadronic Tags: 32K D+ 60K D0

eKD0

Events

/ (

10

MeV

)(~1300 events)

U = Emiss– |Pmiss| (GeV)

CLNS 05-1906 and CLNS 05-1915 to besubmitted to PRL


More Cabibbo allowed modes


Events

/ (

10

MeV

)

Events

/ (

10

MeV

)

Events

/ (

10

MeV

)

(~550 events)



cs Cabibbo Favored 55.8 pb-1 Data

(~90 events)

(~420 events)

Historically Cabibbo allowed modes: provide a significantbackground to Cabibbosuppressed modes, makingthe latter particularlychallenging…..

D+K0e+D+K*0e+K*0K-+

D0 K*-e+K*-K-0


Cabibbo suppressed modes0D e

0D e


Events

/ (

10

MeV

)

(~110 events)

Events

/ (

10

MeV

)

eD 0

(~65 events)


55.8 pb-1 Data

Compare to:state of the art measurementat 10 GeV (CLEO III)PRL 94, 11802

Note:kinematicseparation.

Tag with D*DpObservable: m=mD*-mD.

m


*0D K e n+ +®

2(GeV/c )mpp


(~30 events)


(~30 events)

(8 events) (5)

1st Observation1st Observation

E791 Phys.Lett.B397:325-332,(1997)Relative rate:

S/N ~1/2S/N ~15/1

More Cabibbo supressed modes - 55.8 pb-1

Only measurementuntil now

D+e+

D+e+

D0e+

D0 K*-e+K*-K-0

eKD

eD0*

0



Exclusive Semileptonic D Decays

Preliminary

Now (55.8 pb-1):

Will also measure D+sK0e+,K*0e+,e+

in run above DsDs threshold

CLEO-c already all modes more precise than PDG.

to be submitted to PRL


Decay Constants, FF, |Vcs| and |Vcd|

c

du or

e+

W+

ds or

du or

|Vcs| or |Vcd|Use ratio of semileptonic to leptonic branching ratios to eliminate CKM element and isolate hadronic terms:

2

22

31

22

0

02

22

13

DKm

m

D

edqd

f

qfpmm

D

eKD

D

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 |Vcd| of ~few% (presently 7%) from D++ and De•Error on |Vcs| of ~few% (presently 16%) from Ds

++, Ds

++ and DKl


Differential Semileptonic Rates PPe

D0→K-e+ν D0→π-e+ν

2 2 2cs,d2

|V | |f (q )|q

d

d

Raw q2 No efficiency correction

2q

d

d

2q

CLEO PRL 94/, 11802

(PRL 94, 011601 (2005)

STATUS2005 (CLEO IIIFOCUS BES II)

LQCD : shape & rate correct: precision~10%

22

2

2

~ 0.4GeV CLEO q

~ 0.025 GeV CLEO-c

q

(1) No kinematic ambiguity (2) rest frame of D q2 resolution x 16 better

e

Ke

CLEO-c

2

d

dq

shape

rate

First unquenched LQCD for D/K e


U = Emiss - Pmiss

CLEO-c: PS PS & PS V absolute form factor magnitudes & slopes to a few%. Stringent test of theory! (Unique)

D0 l

D0 Kldp

d

(GeV/c)p

CLEO-c MC

Lattice QCD

dp

dD0 l

D0 l

CLEO-c MC

(GeV/c)p

1fb-1

(D+ l(D+ lindependent of Vcd tests amplitudes ~few%

(DsKln) / (Dsl) independent of Vcs tests amplitudes ~ few%

Vcs/Vcs=few%(now~11%) Vcd/Vcd=few%(now: 5.4%)D Ke

Testing the Lattice with (semi)leptonic Charm Decays

D e

Then Tested lattice to calc. Bl is available for precise exclusive Vub

1fb-1


Inclusive Semileptonic D Decays

Preliminary

CLEO-c (in D rest frame)


Inclusive Semileptonic D Decays

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

Technique:

CLEO-c(stat.)<0.2%<0.2%


Hadronic D Decays

e+ e-

DX

ijjiDDij BBNN iiDDi BNN

Single tagged Double tagged

e+ e-

DXj

DXi DXi

ij

j

j

iji

ji

ij

ij

jiDD

N

NB

N

NNN

Independent ofintegrated luminosity!

K

K

Submitted to PRLhep-ex/0504003


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 K0

s efficiencies still undergoing refinements

Include effects of final state radiation (FSR)

KKKK

KKKD

KKKD

SS

S

, ,

, , ,

, ,

000

00

00


Absolute Charm Branching Ratios at Threshold

# ( )Observed in tagged events( )

detection efficiency for ( ) #D tags

KB D K

K

Independent ofIndependent ofL and cross L and cross sectionsection

Single tags

D candidate mass (GeV)

Double tags

D K

,

D

D K

K

2 2| |BC beam DM E p

D candidate mass (GeV)

Dbeam EEE Kinematics analogous to (4S)BB: identify D with

(MBC) ~ 1.3 MeV, x2 with 0

(E) ~ 7—10 MeV, x2 with 0

:D beamE E

15120±180 377±20

: 10 /D beam bc bcE E M M


(log scale)!

2484±51(combine

d)

1650±42(combined)

6 D+ Modes6 D+ Modes3 D0 Modes3 D0 Modes

Single tags Double tags

Signal shape: (3770) line shape, ISR, beam energy spread & momentum resolution, Bgkd: ARGUS

Global fit pioneered by Mark IIINDD & Bi’s extracted from single and double tag yields with 2 minimization technique.

D0 D0

D+ D+

i i iDDN N B ijjiDDij BBNN

ij ji

j ij

i j ij

DDij i j

NB

N

N NN

N


submitted to PRL

Stat. errors: ~2.0% neutral, ~2.5% charged(systematic) ~ (statistical).

syst. dominatesMany systematics evaluated using data so will shrink as L

D0 ModesD+ Modes

Normalized to PDG

six modes more precise than PDG.

(DD)=6.390.10+0.17 –0.08 nb 01.002.078.0

00

DDee

DDee


Comparison with PDG 2004

B (%) Error(%) Source

3.820.070.1 3.6 CLEO

3.820.090.1 3.8 ALEPH

3.80 0.09 2.4 PDG

3.910.08 0.09 3.1 CLEO-c

CLEO & ALEPHD*++Do, Do K-+ compare to:D*++Do, Do unobserved(Q~6MeV)

THEN:

NOW:

Do K-+

CLEO-c as precise as anyprevious measurement

+

thrust

CLEO-c


1

0

Decay / (%)

2004 1

2.4 3.1 0.5( )(1.3)

7.7 3.9 0.6( )(1.5)

12.5% ( ) 3.2S

B B

PDG CLEO fb

D K stat sys

D K stat sys

D BABAR

CLEO-c will set absolute scale for all heavy quark measurements

B (%) Error(%) Source

9.30.60.8 10.8 CLEO

9.11.30.4 14.9 MKIII

9.10.7 7.7 PDG

9.52 0.250.27 3.9 CLEO-c

0 0*

* 0

( )

( ( ))

( )B D BD

B D D

D

D K

K

B

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

Mostprecise


Impact of CLEO-c Measurements

Results from ~55.8 pb-1: Accumulated ~281 pb-1

Leptonic Charm Decays – D++, Ds+ +,+ Measure decay constants fD, fDs ~few% Improved fB possible from CLEO-c fD measurement + LQCD

Semileptonic Charm Decays – D0,D+K(*)l, (l - Ds+ K(*)l, ()l

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 – D0K, D+K, Ds+ Important for |Vcb|

Vcd Vcs Vcb Vub Vtd Vts

7% 16% 5% 15% 36% 39%

few% few% few%

few%

few%

few%

PDG

B-Factory/Tevatron Data & CLEO-c Lattice Validation

PDG

CLEO-c data and LQCD


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:


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 systemBABAR/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.


Other CLEO Physics Not Covered

(3770) Search for CPV, rare decays DKee, mixing Rich program of Dalitz plot analyses important for CKM angle

Measurement of D0/D0 relative strong phase Separate measurements of B(D->K S,L)

Search for nonDD final states

’ + other charmonia... lots of results Observation of hc, 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-,00,,’ , ee

’b->b transitions

hidden beauty to open charm

1 Recent Results from CLEO-c & CESR-c: A New Frontier in Weak and Strong Interactions David Asner,...

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