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arXiv · 1403.5586

Measurements of Direct CP-Violating Asymmetries in Charmless Decays of Bottom Baryons

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·M. Cavalli-Sforza·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
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Abstract

We report final measurements of direct $\mathit{CP}$--violating asymmetries in charmless decays of neutral bottom hadrons to pairs of charged hadrons with the upgraded Collider Detector at the Fermilab Tevatron. Using the complete $\sqrt{s}=1.96$ TeV proton-antiproton collisions data set, corresponding to 9.3 fb$^{-1}$ of integrated luminosity, we measure $\mathcal{A}(Λ^0_b \rightarrow pπ^{-}) = +0.06 \pm 0.07\mathrm{(stat)} \pm 0.03\mathrm{(syst)}$ and $\mathcal{A}(Λ^0_b \rightarrow pK^{-}) = -0.10 \pm 0.08\mathrm{(stat)} \pm 0.04\mathrm{(syst)}$, compatible with no asymmetry. In addition we measure the $\mathit{CP}$--violating asymmetries in $B^0_s \rightarrow K^{-}π^{+}$ and $B^0 \rightarrow K^{+}π^{-}$ decays to be $\mathcal{A}(B^0_s \rightarrow K^{-}π^{+}) = +0.22 \pm 0.07\mathrm{stat)} \pm 0.02\mathrm{(syst)}$ and $\mathcal{A}(B^0 \rightarrow K^{+}π^{-}) = -0.083\pm 0.013 \mathrm{(stat)} \pm 0.004\mathrm{(syst)}$, respectively, which are significantly different from zero and consistent with current world averages.

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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, M. Cavalli-Sforza, 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. 2014-12-11. Measurements of Direct CP-Violating Asymmetries in Charmless Decays of Bottom Baryons. https://doi.org/10.1103/physrevlett.113.242001

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