D→Kπππ Decays and a Measurement of the

CKM angle γLauren Martin, University of Oxford

Outline γ

γ

Importance of Measuring γ

γγ

γγ

γγ‘’

⇒γγ

Measurement of γusing B±→DK±

γγγB±→D0K±

D0γγ

γγγ⇒‘’

γγD0

γγ

‘ADS’ method

• ‘’D0γγ. K+π−

• γγγ

• γγγγ

Four-Body ADS →

D0

D0

γγ

γ

CLEO-c Measurement of RK3π

δK3π RK3π

γγ

+- →→

γγδK3π

RK3π

γγ

γγ

Preliminary Results

• Kπππ VS CP RK3π δK3π γγγ

• Kπππ VS Kπππ RK3π )2 RK3π

γ• Kπππ VS Kπ RK3π

δK3πδKπ

• δKπ

Impact on LHCb

• The figure illustrates the impact of the results on the sensitivity to γ at LHCb

• Sensitivity to γ dependent on δDKπ, the

sensitivty to γ increases by ∼ 2o due to these measurements

Dalitz Analysis

’γ

γγγ

γ

γγ€

D0 → K −π +π +π −

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D 0 → K −π +π +π −

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KSππ

CLEO-c Measurements

γ

γγ

γ

08/12/07

CP even tagged Flavor TaggedCP odd tagged

€

M2

π +π −

€

(770)

D decay Model

Summary & Conclusions

γ

γ

γ

γ