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arXiv · 1410.5435

Measurement of indirect CP-violating asymmetries in $D^0\to K^+K^-$ and $D^0\to π^+π^-$ decays at CDF

CDF Collaboration·T. Aaltonen·S. Amerio·D. Amidei·A. Anastassov·A. Annovi·J. Antos·G. Apollinari·J. A. Appel·T. Arisawa·A. Artikov·J. Asaadi·W. Ashmanskas·B. Auerbach·A. Aurisano·F. Azfar·W. Badgett·T. Bae·A. Barbaro-Galtieri·V. E. Barnes·B. A. Barnett·P. Barria·P. Bartos·M. Bauce·F. Bedeschi·S. Behari·G. Bellettini·J. Bellinger·D. Benjamin·A. Beretvas·A. Bhatti·K. R. Bland·B. Blumenfeld·A. Bocci·A. Bodek·D. Bortoletto·J. Boudreau·A. Boveia·L. Brigliadori·C. Bromberg·E. Brucken·J. Budagov·H. S. Budd·K. Burkett·G. Busetto·P. Bussey·P. Butti·A. Buzatu·A. Calamba·S. Camarda·M. Campanelli·F. Canelli·B. Carls·D. Carlsmith·R. Carosi·S. Carrillo·B. Casal·M. Casarsa·A. Castro·P. Catastini·D. Cauz·V. Cavaliere·A. Cerri·L. Cerrito·Y. C. Chen·M. Chertok·G. Chiarelli·G. Chlachidze·K. Cho·D. Chokheli·A. Clark·C. Clarke·M. E. Convery·J. Conway·M. Corbo·M. Cordelli·C. A. Cox·D. J. Cox·M. Cremonesi·D. Cruz·J. Cuevas·R. Culbertson·N. d'Ascenzo·M. Datta·P. de Barbaro·L. Demortier·L. Marchese·M. Deninno·F. Devoto·M. D'Errico·A. Di Canto·B. Di Ruzza·J. R. Dittmann·M. D'Onofrio·S. Donati·M. Dorigo·A. Driutti·K. Ebina·R. Edgar·A. Elagin
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Abstract

We report a measurement of the indirect CP-violating asymmetries ($A_Γ$) between effective lifetimes of anticharm and charm mesons reconstructed in $D^0\to K^+ K^-$ and $D^0\to π^+π^-$ decays. We use the full data set of proton-antiproton collisions collected by the Collider Detector at Fermilab experiment and corresponding to $9.7$~fb$^{-1}$ of integrated luminosity. The strong-interaction decay $D^{*+}\to D^0π^+$ is used to identify the meson at production as $D^0$ or $\overline{D}^0$. We statistically subtract $D^0$ and $\overline{D}^0$ mesons originating from $b$-hadron decays and measure the yield asymmetry between anticharm and charm decays as a function of decay time. We measure $A_Γ(K^+K^-) = (-0.19 \pm 0.15 (stat) \pm 0.04 (syst))\%$ and $A_Γ(π^+π^-)= (-0.01 \pm 0.18 (stat) \pm 0.03 (syst))\%$. The results are consistent with the hypothesis of CP symmetry and their combination yields $A_Γ= (-0.12 \pm 0.12)\%$.

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CDF Collaboration, T. Aaltonen, S. Amerio, D. Amidei, A. Anastassov, A. Annovi, J. Antos, G. Apollinari, J. A. Appel, T. Arisawa, A. Artikov, J. Asaadi, W. Ashmanskas, B. Auerbach, A. Aurisano, F. Azfar, W. Badgett, T. Bae, A. Barbaro-Galtieri, V. E. Barnes, B. A. Barnett, P. Barria, P. Bartos, M. Bauce, F. Bedeschi, S. Behari, G. Bellettini, J. Bellinger, D. Benjamin, A. Beretvas, A. Bhatti, K. R. Bland, B. Blumenfeld, A. Bocci, A. Bodek, D. Bortoletto, J. Boudreau, A. Boveia, L. Brigliadori, C. Bromberg, E. Brucken, J. Budagov, H. S. Budd, K. Burkett, G. Busetto, P. Bussey, P. Butti, A. Buzatu, A. Calamba, S. Camarda, M. Campanelli, F. Canelli, B. Carls, D. Carlsmith, R. Carosi, S. Carrillo, B. Casal, M. Casarsa, A. Castro, P. Catastini, D. Cauz, V. Cavaliere, A. Cerri, L. Cerrito, Y. C. Chen, M. Chertok, G. Chiarelli, G. Chlachidze, K. Cho, D. Chokheli, A. Clark, C. Clarke, M. E. Convery, J. Conway, M. Corbo, M. Cordelli, C. A. Cox, D. J. Cox, M. Cremonesi, D. Cruz, J. Cuevas, R. Culbertson, N. d'Ascenzo, M. Datta, P. de Barbaro, L. Demortier, L. Marchese, M. Deninno, F. Devoto, M. D'Errico, A. Di Canto, B. Di Ruzza, J. R. Dittmann, M. D'Onofrio, S. Donati, M. Dorigo, A. Driutti, K. Ebina, R. Edgar, A. Elagin. 2015-01-06. Measurement of indirect CP-violating asymmetries in $D^0\to K^+K^-$ and $D^0\to π^+π^-$ decays at CDF. https://doi.org/10.1103/physrevd.90.111103

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