We have measured the charge asymmetry in the decay $\eta \to {\pi }^{+}{\pi }^{-}{\pi }^0$. $\eta \text{'}\mathrm{s}$ were produced in the reaction ${\pi }^{-}p\to \eta n$ at 730 and 810 $\frac{\mathrm{MeV}}{c}$ incident pion momentum. We obtain an asymmetry of -0.0005 ± 0.0022 for 220 659 events. We see no evidence for $C$-invariance violation in this decay.

• Received 25 April 1972

DOI:https://doi.org/10.1103/PhysRevLett.29.316