%0 Journal Article %T Measurement of the Time-Integrated CP Asymmetry in D0 → K- K+ Decays %A LHCb Collaboration (Aaij, R. et al %A Jaimes Elles, S. J. %A Jashal, B. K. %A Martinez-Vidal, F. %A Oyanguren, A. %A Rebollo De Miguel, M. %A Remon Alepuz, C. %A Ruiz Vidal, J. %A Sanderswood, I. %J Physical Review Letters %D 2023 %V 131 %N 9 %I Amer Physical Soc %@ 0031-9007 %G English %F LHCbCollaborationAaij_etal2023 %O WOS:001091049600002 %O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=5810), last updated on Wed, 10 Apr 2024 12:44:52 +0000 %X The time-integrated CP asymmetry in the Cabibbo suppressed decay PKK is measured using proton proton collision data, corresponding to an integrated luminosity of 5.7 th collected at a center of mass energy of 13 TeV with the LHCb detector. The D mesons are required to originate from promptly produced DD's decays, and the charge of the companion pion is used to determine the flavor of the charm meson at production. The time integrated CP asymmetry is measured to be Acr(KK) 6,815.41.6 x 10 where the first uncertainty is statistical and the second systematic. The direct CP asymmetries in D-K-K and D -> decays, and are derived by combining Ace(KK) with the time integrated CP asymmetry differ ence, AAcr-Acr(KK)-A(x), and other inputs, giving a (7.715.7) x 10, (23.2 16.1) x 10, with a correlation coefficient corresponding to p=0.88. The compatibility of these results with CP symmetry is 1.4 and 3.8 standard deviations for DKK and D degrees-xx decays, respectively. This is the first evidence for direct CP violation in a specific Do decay. %R 10.1103/physRevLett.131.091802 %U https://arxiv.org/abs/2209.03179 %U https://doi.org/10.1103/physRevLett.131.091802 %P 091802-13pp