1. Beyond the Standard Model: the clue from charm ...
Precision study of b and c decays
deviations in expected behaviour of
b and c quarks evidence for new physics +
will elucidate new physics if found elsewhere
Rare decays
Mixing & CPV
..the clue from charm

2. Precision measurements of the D+ and Ds decay constants
To use the full power of b and c decays, theoretical calculations of strong interactions must be used.
The lattice gauge approach promises precision calculations that must be confronted with data
Precision measurements of the D+ and Ds decay constants
Semileptonic charm decay measurements Vcd and Vcs directly as well as input on hadronic matrix element
..the clue from charm

3. Direct signatures for new physics in charm decays
Bigi-Sanda hep-ph/
“A priori it is quite conceivable that qualitatively different forces
drive the decays of up-type and down-type quarks .
More specifically, non-Standard-Model forces might exhibit
a very different pattern for the two classes of quarks”.
Charm decays are the only up-type quarks that allow
to probe this physics:non-strange light flavour hadrons do not
allow for oscillations and top-flavoured hadrons do not even
form in a practical way
..the clue from charm

4. BaBar measurement is @ 57.1 fb-1
Mixing & CPV
Motivation: suppressed in the charm sector in the SM. If “measured”, would suggest SM extention
BaBar measurement 57.1 fb-1
..the clue from charm

5. New limits expected by BaBar and Belle Cleo-c @ 95% C.L. CP violation
Direct CP violation in D0 and D+
Indirect CP violation in D0 decays
CP violation measurements exploiting the quantum coherence of the D0 D0bar produced pair
y(3770)  DD ; JP=1-
CP violation asymmetry sensitivity
ACP< @ Cleo-c and Beauty Factories
..the clue from charm

6. CDF and D0 can trigger on dimuons promising
Rare decays
Motivation: lepton number violation study
investigation of long range effects and SM extention
FOCUS improved results by a factor of 1.7 –14: approaching theoretical predictions for some of the modes but still far for the majority
CDF Br(D0m+m-)<2.4 90% C.L.
is the best limit for this mode (65 pb-1 data)
CDF and D0 can trigger on dimuons promising
Cleo-c sensitivity 10-6
..the clue from charm

7. Leptonic decays Motivations: decay constants measurements
Lattice predicts fB/fD & fBs/fDs with small errors
..the clue from charm

8. Hadronic and semileptonic decays
Over constrain the “Unitarity Triangle”
Inconsistencies New Physics
semileptonic decays are the easiest way
to determine CKM elements:QCD effects contained in form factors.
Comparison with LGT and quark model calculations!
..the clue from charm

9. Status of CKM Matrix Current VCKM From direct Measurements B
Vub/Vub 17% l n B p D
Vcd/Vcd 7% K
Vcs/Vcs =11%
Vcb/Vcb 5% Bd
Vtd/Vtd =36% Bs
Vts/Vts 39%
Vus/Vus =1% 
Vud/Vud 0.1% e
Vtb/Vtb 29% t b W
Current VCKM
From direct
Measurements
-no unitarity
imposed
CLEO-c will redefine 2nd generation elements
And enable improvements in 3rd generation
..the clue from charm

10. Potential Impact on VCKM
Vub/Vub 17% l n B p D
Vcd/Vcd 7% K
Vcs/Vcs 11%
Vcb/Vcb 5% Bd
Vtd/Vtd 36% Bs
Vts/Vts 39%
Vus/Vus 1% 
Vud/Vud 0.1% e
Vtb/Vtb 29% t b W
Current VCKM
From direct
Measurements
-no unitarity
imposed 2% 5% 3%
Future VCKM
CLEO-c will redefine 2nd generation elements
And enable improvements in 3rd generation
..the clue from charm

11. Summary of reach
..the clue from charm