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arXiv · 1308.1120

Measurement of the leptonic asymmetry in ttbar events produced in ppbar collisions at sqrt(s)=1.96 TeV

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 measure the asymmetry in the charge-weighted rapidity of the lepton in semileptonic ttbar decays recorded with the CDF II detector using the full Tevatron Run II sample, corresponding to an integrated luminosity of 9.4/fb. A parametrization of the asymmetry as a function of the charge-weighted rapidity is used to correct for the finite acceptance of the detector and recover the production-level asymmetry. The result of afb(lep) = 0.094 +0.032 -0.029 is to be compared to the standard model next-to-leading-order prediction of afb(lep) = 0.038 +-0.003.

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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. 2013-08-05. Measurement of the leptonic asymmetry in ttbar events produced in ppbar collisions at sqrt(s)=1.96 TeV. https://doi.org/10.1103/physrevd.88.072003

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