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arXiv · 1011.6549

Measurement of the W boson helicity in top quark decays using 5.4 fb^-1 of ppbar collision data

V. M. Abazov·B. Abbott·B. S. Acharya·M. Adams·T. Adams·G. D. Alexeev·G. Alkhazov·A. Altona·G. Alverson·G. A. Alves·L. S. Ancu·M. Aoki·Y. Arnoud·M. Arov·A. Askew·B. Asman·O. Atramentov·C. Avila·J. BackusMayes·F. Badaud·L. Bagby·B. Baldin·D. V. Bandurin·S. Banerjee·E. Barberis·P. Baringer·J. Barreto·J. F. Bartlett·U. Bassler·V. Bazterra·S. Beale·A. Bean·M. Begalli·M. Begel·C. Belanger-Champagne·L. Bellantoni·S. B. Beri·G. Bernardi·R. Bernhard·I. Bertram·M. Besancon·R. Beuselinck·V. A. Bezzubov·P. C. Bhat·V. Bhatnagar·G. Blazey·S. Blessing·K. Bloom·A. Boehnlein·D. Boline·T. A. Bolton·E. E. Boos·G. Borissov·T. Bose·A. Brandt·O. Brandt·R. Brock·G. Brooijmans·A. Bross·D. Brown·J. Brown·X. B. Bu·M. Buehler·V. Buescher·V. Bunichev·S. Burdinb·T. H. Burnett·C. P. Buszello·B. Calpas·E. Camacho-Perez·M. A. Carrasco-Lizarraga·B. C. K. Casey·H. Castilla-Valdez·S. Chakrabarti·D. Chakraborty·K. M. Chan·A. Chandra·G. Chen·S. Chevalier-Thery·D. K. Cho·S. W. Cho·S. Choi·B. Choudhary·T. Christoudias·S. Cihangir·D. Claes·J. Clutter·M. Cooke·W. E. Cooper·M. Corcoran·F. Couderc·M. -C. Cousinou·A. Croc·D. Cutts·M. Cwiok·A. Das·G. Davies·K. De·S. J. de Jong·E. De La Cruz-Burelo
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Abstract

We present a measurement of the helicity of the W boson produced in top quark decays using ttbar decays in the l+jets and dilepton final states selected from a sample of 5.4 fb^-1 of collisions recorded using the D0 detector at the Fermilab Tevatron ppbar collider. We measure the fractions of longitudinal and right-handed W bosons to be f_0 = 0.669 +- 0.102 [ +- 0.078 (stat.) +- 0.065 (syst.)] and f_+ = 0.023 +- 0.053 [+- 0.041 (stat.) +- 0.034 (syst.)], respectively. This result is consistent at the 98% level with the standard model. A measurement with f_0 fixed to the value from the standard model yields f_+ = 0.010 +- 0.037 [+- 0.022 (stat.) +- 0.030 (syst.) ].

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V. M. Abazov, B. Abbott, B. S. Acharya, M. Adams, T. Adams, G. D. Alexeev, G. Alkhazov, A. Altona, G. Alverson, G. A. Alves, L. S. Ancu, M. Aoki, Y. Arnoud, M. Arov, A. Askew, B. Asman, O. Atramentov, C. Avila, J. BackusMayes, F. Badaud, L. Bagby, B. Baldin, D. V. Bandurin, S. Banerjee, E. Barberis, P. Baringer, J. Barreto, J. F. Bartlett, U. Bassler, V. Bazterra, S. Beale, A. Bean, M. Begalli, M. Begel, C. Belanger-Champagne, L. Bellantoni, S. B. Beri, G. Bernardi, R. Bernhard, I. Bertram, M. Besancon, R. Beuselinck, V. A. Bezzubov, P. C. Bhat, V. Bhatnagar, G. Blazey, S. Blessing, K. Bloom, A. Boehnlein, D. Boline, T. A. Bolton, E. E. Boos, G. Borissov, T. Bose, A. Brandt, O. Brandt, R. Brock, G. Brooijmans, A. Bross, D. Brown, J. Brown, X. B. Bu, M. Buehler, V. Buescher, V. Bunichev, S. Burdinb, T. H. Burnett, C. P. Buszello, B. Calpas, E. Camacho-Perez, M. A. Carrasco-Lizarraga, B. C. K. Casey, H. Castilla-Valdez, S. Chakrabarti, D. Chakraborty, K. M. Chan, A. Chandra, G. Chen, S. Chevalier-Thery, D. K. Cho, S. W. Cho, S. Choi, B. Choudhary, T. Christoudias, S. Cihangir, D. Claes, J. Clutter, M. Cooke, W. E. Cooper, M. Corcoran, F. Couderc, M. -C. Cousinou, A. Croc, D. Cutts, M. Cwiok, A. Das, G. Davies, K. De, S. J. de Jong, E. De La Cruz-Burelo. 2010-11-30. Measurement of the W boson helicity in top quark decays using 5.4 fb^-1 of ppbar collision data. https://doi.org/10.1103/physrevd.83.032009

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