Measurement of CP-violating asymmetries in D-0 -> pi(+) pi(-) and D-0 -> K+ K- decays at CDF

We report on a measurement of CP-violating asymmetries (A CP) in the Cabibbo-suppressed D0→π +π - and D0→K +K - decays reconstructed in a data sample corresponding to 5.9fb -1 of integrated luminosity collected by the upgraded Collider Detector at Fermilab. We use the strong decay D *+→D0π + to iden...

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Bibliographic Details
Main Authors: Aaltonen, T, Alvarez Gonzalez, B, Amerio, S, Amidei, D, Anastassov, A, Annovi, A, Antos, J, Apollinari, G, Appel, J, Arisawa, T, Artikov, A, Asaadi, J, Ashmanskas, W, Auerbach, B, Aurisano, A, Azfar, F, Badgett, W, Bae, T, Barbaro-Galtieri, A, Barnes, V, Barnett, B, Barria, P, Bartos, P, Bauce, M, Bedeschi, F
Format: Journal article
Language:English
Published: 2012
Description
Summary:We report on a measurement of CP-violating asymmetries (A CP) in the Cabibbo-suppressed D0→π +π - and D0→K +K - decays reconstructed in a data sample corresponding to 5.9fb -1 of integrated luminosity collected by the upgraded Collider Detector at Fermilab. We use the strong decay D *+→D0π + to identify the flavor of the charmed meson at production and exploit CP-conserving strong cc̄ pair production in pp̄ collisions. High-statistics samples of Cabibbo-favored D0→K -π + decays with and without a D *± tag are used to correct for instrumental effects and significantly reduce systematic uncertainties. We measure A CP(D0→π +π -)=(+0.22±0.24(stat) ±0.11(syst))% and A CP(D0→K +K -)=(-0.24±0.22(stat)±0.09(syst))%, in agreement with CP conservation. These are the most precise determinations from a single experiment to date. Under the assumption of negligible direct CP violation in D0→π +π - and D0→K +K - decays, the results provide an upper limit to the CP-violating asymmetry in D0 mixing, |ACPind(D0)|<0.13% at the 90% confidence level. © 2012 American Physical Society.