Document Type
Article
Publication Date
7-23-2010
Abstract
We report measurements of the polarization of W bosons from top-quark decays using 2.7 fb-1 of pp̄ collisions collected by the CDF II detector. Assuming a top-quark mass of 175GeV/c2, three measurements are performed. A simultaneous measurement of the fraction of longitudinal (f0) and right-handed (f+) W bosons yields the model-independent results f0=0.88±0.11(stat)±0.06(syst) and f+=-0.15±0.07(stat) ±0.06(syst) with a correlation coefficient of -0.59. A measurement of f0 [f+] constraining f+ [f0] to its standard model value of 0.0 [0.7] yields f0=0.70±0.07(stat)±0.04(syst) [f+=-0.01±0.02(stat) ±0.05(syst)]. All these results are consistent with standard model expectations. We achieve the single most precise measurements of f0 for both the model-independent and model-dependent determinations. © 2010 The American Physical Society.
Publication Source (Journal or Book title)
Physical Review Letters
Recommended Citation
Aaltonen, T., Adelman, J., Álvarez González, B., Amerio, S., Amidei, D., Anastassov, A., Annovi, A., Antos, J., Apollinari, G., Appel, J., Apresyan, A., Arisawa, T., Artikov, A., Asaadi, J., Ashmanskas, W., Attal, A., Aurisano, A., Azfar, F., Badgett, W., Barbaro-Galtieri, A., Barnes, V., Barnett, B., Barria, P., Bartos, P., Bauer, G., Beauchemin, P., Bedeschi, F., & Beecher, D. (2010). Measurement of w-boson polarization in top-quark decay in pp̄ collisions at √s=1.96TeV. Physical Review Letters, 105 (4) https://doi.org/10.1103/PhysRevLett.105.042002