PT Journal
AU BABAR Collaboration (del Amo Sanchez, Pea
   Lopez-March, N
   Martinez-Vidal, F
   Milanes, DA
   Oyanguren, A
TI Studies of tau(-) -> eta K- nu(tau) and tau(-) -> eta pi(-) nu(tau) at BABAR and a search for a second-class current
SO Physical Review D
JI Phys. Rev. D
PY 2011
BP 032002
EP 10pp
VL 83
IS 3
DI 10.1103/PhysRevD.83.032002
LA English
AB We report on analyses of tau lepton decays tau(-) -> eta K- nu(tau) and tau(-) -> eta pi(-) nu(tau), with eta -> pi(+) pi(-) pi(0), using 470 fb(-1) of data from the BABAR experiment at PEP-II, collected at center-of-mass energies at and near the Y(4S) resonance. We measure the branching fraction for the tau(-) -> eta K- nu(tau) decay mode, B(tau(-) -> eta K- nu(tau)) = (1.42 +/- 0.11(stat) +/- 0.07(syst)) x 10(-4), and report a 95% confidence level upper limit for the second-class current process tau(-) -> eta pi(-) nu(tau), B(tau(-) -> eta pi(-) nu(tau)) < 9.9 x 10(-5).
ER