We report the combination of recent measurements of the helicity of the W boson from top quark decay by the CDF and D0 collaborations, based on data samples corresponding to integrated luminosities of 2.7-5.4 fb(-1) of p (p) over bar collisions collected during Run II of the Fermilab Tevatron collider. Combining measurements that simultaneously determine the fractions of W bosons with longitudinal (f(0)) and right-handed (f(+)) helicities, we find f(0) = 0.722 +/- 0.081[+/- 0.062(stat) +/- 0.052(syst)] and f(+) = -0.033 +/- 0.046[+/- 0.034(stat) +/- 0.031(syst)]. Combining measurements where one of the helicity fractions is fixed to the value expected in the standard model, we find f(0) = 0.682 +/- 0.057[+/- 0.035(stat) +/- 0.046(syst)] for fixed f(+) and f(+) = -0.015 +/- 0.035[+/- 0.018(stat) +/- 0.030(syst)] for fixed f(0). The results are consistent with standard model expectations. RI Dudko, Lev/D-7127-2012; Perfilov, Maxim/E-1064-2012; Karmanov, Dmitry/E-2242-2012; Boos, Eduard/D-9748-2012; Prokoshin, Fedor/E-2795-2012; maestro, paolo/E-3280-2010; Johnson, Mark/B-6921-2009; Gutierrez, Phillip/C-1161-2011; song, hao/I-2782-2012; Merkin, Mikhail/D-6809-2012; manca, giulia/I-9264-2012
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