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Extracting CP violation and strong phase in D decays by using quantum correlations in psi(3770)-> D0bar{D}0 -> (V1V2)(V3V4) and psi(3770)->D0bar{D}0 -> (V1V2)(K pi)

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 نشر من قبل S. Descotes-Genon
 تاريخ النشر 2009
  مجال البحث
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The charm quark offers interesting opportunities to cross-check the mechanism of CP violation precisely tested in the strange and beauty sectors. In this paper, we exploit the angular and quantum correlations in the Dbar{D} pairs produced through the decay of the psi(3770) resonance in a charm factory to investigate CP-violation in two different ways. We build CP-violating observables in psi(3770) -> Dbar{D} -> (V_1V_2)(V_3 V_4) to isolate specific New Physics effects in the charm sector. We also consider the case of psi(3770) -> Dbar{D} -> (V_1V_2)(Kpi) decays, which provide a new way to measure the strong phase difference delta between Cabibbo-favored and doubly-Cabibbo suppressed D decays required in the determination of the CKM angle gamma. Neglecting the systematics, we give a first rough estimate of the sensitivities of these measurements at BES-III with an integrated luminosity of 20 fb^-1 at psi(3770) peak and at a future Super tau-charm factory with a luminosity of 10^35 cm^-2.s^-1.

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