Observation of radiative leptonic decay of the tau lepton
Using 4.68 fb(-1) of e(+)e(-) annihilation data collected with the CLEO II detector at the Cornell Electron Storage Ring, we have studied tau radiative decays tau(-)-->nu(tau)&mgr;(-)nu;(&mgr;)gamma and tau(-)-->nu(tau)e(-)nu;(e)gamma. For a 10 MeV minimum photon energy in the tau rest frame, the branching fraction for radiative tau decay to a muon or electron is measured to be (3.61+/-0.16+/-0. 35)x10(-3) or (1.75+/-0.06+/-0.17)x10(-2), respectively. The branching fractions are in agreement with standard model theoretical predictions.
Viehhauser
G
University of Illinois, Urbana-Champaign, Illinois 61801, USA.
Wang
JC
Wolf
A
Wu
J
Csorna
SE
McLean
KW
Marka
S
Xu
Z
Godang
R
Kinoshita
K
Lai
IC
Schrenk
S
Bonvicini
G
Cinabro
D
Greene
R
Perera
LP
Zhou
GJ
Chan
S
Eigen
G
Lipeles
E
Schmidtler
M
Shapiro
A
Sun
WM
Urheim
J
Weinstein
AJ
Wurthwein
F