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A search for the decay of the tau lepton to five charged and two neutral pions
is performed using data collected by the BABAR detector at
the PEP-II asymmetric-energy e+e- collider.
The analysis uses 232 fb-1 of data at center-of-mass energies on or near the
Y(4S) resonance.
We observe 10 events with an expected background of 6.5^{+2.0}_{-1.4} events.
In the absence of a signal, we set the limit on the branching ratio
B(tau- --> 3pi- 2pi+ 2pi0 nu_tau) < 3.4x10^{-6} at the 90% confidence level.
This is a significant improvement over the previously established limit.
In addition, we search for the decay mode tau- --> 2omega pi- nu_tau.
We observe 1 event with an expected background of 0.4^{+1.0}_{-0.4} events
and calculate the upper limit B(tau- --> 2omega pi- nu_tau) < 5.4x10^{-7} at the
90% confidence level. This is the first upper limit for this mode.
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