Measurement of the W boson polarization in top decay at CDF at s = 1.8 TeV Academic Article uri icon


  • The polarization of the W boson in t Wb decay is unambiguously predicted by the standard model of electroweak interactions and is a powerful test of our understanding of the tbW vertex. We measure this polarization from the invariant mass of the b quark from t Wb and the lepton from W l whose momenta measure the W decay angle and direction of motion, respectively. In this paper we present a measurement of the decay rate (f V+A) of the W produced from the decay of the top quark in the hypothesis of V + A structure of the tWb vertex. We find no evidence for the nonstandard V + A vertex and set a limit on fV+A < 0.80 at 95% confidence level. By combining this result with a complementary observable in the same data, we assign a limit on fv+A < 0.61 at 95% CL. This corresponds to a constraint on the right-handed helicity component of the W polarization of f+ < 0.18 at 95% CL. This limit is the first significant direct constraint on fV+A in top decay. 2005 The American Physical Society.

published proceedings

  • Physical Review D - Particles, Fields, Gravitation and Cosmology

author list (cited authors)

  • Acosta, D., Affolder, T., Albrow, M. G., Ambrose, D., Amidei, D., Anikeev, K., ... Errede, S.

citation count

  • 23

complete list of authors

  • Acosta, D||Affolder, T||Albrow, MG||Ambrose, D||Amidei, D||Anikeev, K||Antos, J||Apollinari, G||Arisawa, T||Artikov, A||Ashmanskas, W||Azfar, F||Azzi-Bacchetta, P||Bacchetta, N||Bachacou, H||Badgett, W||Barbaro-Galtieri, A||Barnes, VE||Barnett, BA||Baroiant, S||Barone, M||Bauer, G||Bedeschi, F||Behari, S||Belforte, S||Bell, WH||Bellettini, G||Bellinger, J||Benjamin, D||Beretvas, A||Bhatti, A||Binkley, M||Bisello, D||Bishai, M||Blair, RE||Blocker, C||Bloom, K||Blumenfeld, B||Bocci, A||Bodek, A||Bolla, G||Bolshov, A||Bortoletto, D||Boudreau, J||Bromberg, C||Brubaker, E||Budagov, J||Budd, HS||Burkett, K||Busetto, G||Byrum, KL||Cabrera, S||Campbell, M||Carithers, W||Carlsmith, D||Castro, A||Cauz, D||Cerri, A||Cerrito, L||Chapman, J||Chen, C||Chen, YC||Chertok, M||Chiarelli, G||Chlachidze, G||Chlebana, F||Chu, ML||Chung, JY||Chung, WH||Chung, YS||Ciobanu, CI||Clark, AG||Coca, M||Connolly, A||Convery, M||Conway, J||Cordelli, M||Cranshaw, J||Culbertson, R||Dagenhart, D||D'Auria, S||De Barbaro, P||De Cecco, S||Dell'Agnello, S||Dell'Orso, M||Demers, S||Demortier, L||Deninno, M||De Pedis, D||Derwent, PF||Dionisi, C||Dittmann, JR||Dominguez, A||Donati, S||D'Onofrio, M||Dorigo, T||Eddy, N||Erbacher, R||Errede, D||Errede, S

publication date

  • January 2005