Measurement of the helicity of W bosons in top quark decays
We use the transverse momentum spectrum of leptons in the decay chain t-->bW with W-->lnu to measure the helicity of the W bosons in the top quark rest frame. Our measurement uses a t&tmacr; sample isolated in 106+/-4 pb(-1) of data collected in p&pmacr; collisions at sqrt[s] = 1.8 TeV with the CDF detector at the Fermilab Tevatron. Assuming a standard V-A weak decay, we find that the fraction of W's with zero helicity in the top rest frame is F0 = 0.91+/-0. 37(stat)+/-0.13(syst), consistent with the standard model prediction of F0 = 0.70 for a top mass of 175 GeV/c(2).
Ukegawa
F
Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Valls
J
Vejcik
S
Velev
G
Vidal
R
Vilar
R
Vologouev
I
Vucinic
D
Wagner
RG
Wagner
RL
Wahl
J
Wallace
NB
Walsh
AM
Wang
C
Wang
CH
Wang
MJ
Watanabe
T
Watts
T
Webb
R
Wenzel
H
Wester
WC
Wicklund
AB
Wicklund
E
Williams
HH
Wilson
P
Winer
BL